Prpscntsb to
of %
JSntligrsttg of ®0rajtto
Professor FredeLrick Tracy
LECTURES
ON
LOGIC
BY
SIR WILLIAM HAMILTON, BART.
PEOPE880R 09 LOGIC AND MKTAPHY8IC8 IN THK UNIVKRSITY OJ- EDINBCnOH
XDITED BY THB
REV. HENRY L. MANSEL. B.D.,LL.D..
TTATirFLBTK PSOFESSOR Or MORAL AND UKTAPHTSICAL rBILOSOI-IIT, O.TPOKD,
AND
JOHN VEITCH, M.A.,
PBOrSSSOB OF LOGIC, EUETOBIC, AMD MBTAPUTSICS, ST. .l.N liliKWS.
NEW Y O K K :
SHELDO]^r A:^rD compain^y,
8 MUKRAY StKKET.
1883.
ON EAr-TH, THERE IS KOTIIINO GUEAT HUT Ma:!'
IK MAN, TUKRE 18 NOTUINO ORKAT Biri MIND.
s/
i> B :e] :Er ^ o Ei .
TflE Lectures comprised in the present Volume form
tile second And concluding portion of the Biennial
Gourde on Metaphysics and Logic, which was com-
menced by Sir William Hamilton on his election to
the Professorial Chair in 1836, and repeated, with but
Blight alterations, till his decease in 1856. The Ap-
f^ndix contains various papers, composed for the most
part during this period, which, though portions of
th«ir contents were publicly taught at least as early
as 184<0, Were only to a very small extent incorporated
into the text of the Lectures.
The Lectures on Logic, like those on Metaphysics,
Were chiefly composed during the session in which they
were first delivered (1837-8) ; and the statements made
in the Preface to the previous volume, as regards the
circumstances and manner of their composition, are
equally applicable to the present course. In this, as
in the preceding series, the Author has largely availed
VI PREFACE.
himself of the labors of previous writers, many of
whom are but little known in this country. To the
works of the German logicians of the present century,
particularly to those of Krug and Esser, these Lectures
are under special obligations.
In the compilation of the Appendix, some responsi-
bility rests with the Editors ; and a few words of ex-
planation may be necessary as regards the manner in
which they have attempted to perform this portion of
then- task. In publishing the papers of a deceased
writer, composed at various intervals during a long
period of years, and treating of difficult and contro-
verted questions, there are two opposite dangers to be
guarded against. On the one hand, there is the dan-
ger of compromising the Author's reputation by the
publication of documents which his maturer judgment
might not have sanctioned; and, on the other hand,
there is the danger of committing an opposite injury
to him and to the public, by withholding writings of
interest and value. Had Sir William Hamilton, at any
period of his life, published a systematic treatise on
Eogic, or had his projected New Analytic of Logical
Forms been left in a state at all approaching to com-
pleteness, the Editors might probably have obtained a
criterion by which to distinguish between those specu-
lations which would have received the final imprimatur
of their Author, and those which would not. In the
PREFACE. VII
absence of any such criterion, they have thought it
better to run the risk of giving too much than too
little ; — to publish whatever appeared to have any
philosophical or historical interest, without being in-
fluenced by its coincidence with their own opinions, or
by its coherence with other parts of the Author's writ-
ings. It is possible that, among the papers thus pub-
lished, may be found some which are to be considered
rather as experimental exercises than as approved re-
sults ; but no papers have been intentionally omitted,
except such as were either too fragmentary to be Intel-
ligible, or manifestly imperfect sketches of what has
been published here or elsewhere in a more matured
form.
The Notes, in this as in the previous volume, are
divided into three classes. Those printed from the
manuscript of the Lectures appear without any dis-
tinctive mark; those supplied from the Author's Com-
monplace-Book and other papers are enclosed within
square brackets without signature ; and those added by
the Editors are marked by the signature "Ed." These
last, as in the Lectures on Metaphysics, are chiefly con-
fined to occasional explanations of the text and verifi-
cations of references.
In conclusion, the Editors desire to express their ac-
knowledgments to those friends from whom they have
received assistance in tracing the numerous quotations
Vni PREFACE.
and allusions scattered through this and the preceding
volume. In particular, their thanks are due to Hubert
Hamilton, Esq., whose researches among his father's
books and papers have supplied them with many val-
uable materials ; and to H. W. Chandler, Esq., Fellow
of Pembroke College, Oxford, who has aided them from
the resources of a philosophical learning cognate in
many respects to that of Sir William Hamilton himself.
COISr TENTS
LECTURE I.
INTRODUCTION.
FAOB.
LOGIC — I. ITS DEFINITION I
LECTURE II.
LOGIC — I.. ITS DEFINITION— HISTORICAL NOTICES OF OPINIONS
REGARDING ITS OBJECT AND DOMAIN — II. ITS UTILITY, . 14
LECTURE III.
LOGIC — II. ITS UTILITY — III. ITS DIVISIONS — SUBJECTIVE AJSD
OBJECTIVE — GENERAL AND SPECIAL, 2»;
LECTURE IV.
,U)GIC — m. ITS DIVISIONS — PURE AND MODIFIEE|, j * , m
LECTURE V.
t
PURE LOGIC.
PART I. STOICHEIOLOGY. — SECTION I. NOETIC. — ON THE FUN-
DAMENTAL LAWS OF THOUGHT — THEIR CONTENTS AND
HISTORY, . . . . . 58-
B
X CONTENTS.
LECTURE VI.
PAOB
THE FUNDAMENTAL LAWS OF THOUGHT - "FHEIR CLASSIFICA-
TION AND IMPORT, 69
LECTURE VII.
SECTION II. OF THE PRODUCTS OF THOUGHT. — I. ENNOEMATIC
— OF CONCEPTS OR NOTIONS — A. OF CONCEPTS IN GEN-
ERAL, 83
LECTURE VIII.
ENNOEMATIC — A. OF CONCEPTS IN GENERAL ; B. IN SPECTAL.
— L THEIR OBJECTIVE RELATION — QUANTITY, . . . .W
LECTURE IX.
ENNOEMATIC. — B. OF CONCEPTS IN SPECIAL. — II. THEIR SUB-
JECTIVE RELATION— QUALITY, Ill
■;p.'
LECTURE X.
ENNOEMATIC. — IMPERFECTION OF CONCEPTS, 121
LECTURE XI.
ENNOEMATIC. — m. RECIPROCAL RELATIONS OF CONCEPTS. — A.
QUANTITY OF EXTENSION — SUBORDINATION AND COORDI-
NATION 132
CONTEIfTS. XI
LECTURE XII.
PAGE
ENNOEMATIC. — III. RECIPROCAL RELATIONS OF CONCEPTS. —B.
QUANTITY OF COMPREHENSION, 150
LECTURE XIII.
JL APOPHANTIC, OR THE DOCTRINE OF JUDGMENTS, — JUDG-
MENTS—THEIR NATURE AND DIVISIONS, .... 159
LECTURE XIV.
APOPHANTIC. — JUDGMENTS — THEIR QUALITY, OPPOSITION, AND
CONVERSION, . 173
LECTURE XV.
HI. DOCTRINE OF REASONINGS. — REASONING IN GENERAL. —
SYLLOGISMS — THEIR DIVISIONS ACCORDING TO INTERNAL
FORM, 189
LECTURE XVI.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO INTERNAL FORM. — A. SIMPLE — CATEGORI-
CAL. — I. DEDUCTIVE IN EXTENSION, ..... 206
LECTURE XVII.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO INTERNAL FORM. — A. SIMPLE — CATEGORI-
CAL. — II. DEDUCTIVE IN COMPREHENSION. — IIL INDUCTIVE
IN EXTENSION AND COMPREHENSION. — B. CONDITIONAL-:
DISJUNCTIVE, 221
LECTURE XVIII.
PAQR
DOCTRINE OF «EASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO INTERNAL FORM. — B. CONDITIONAL — HY-
POTHETICAL AND HYPOTHETICO-DISJUNCTIVE, ... 239
LECTURE XIX.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO EXTERNAL FORM. — A. COMPLEX — EPI-
CHEIREMA AND SORITES, .2.57
LECTURE XX.
fi«OGTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO EXTERNAL FORM. - B. DEFECTIVE — EN-
THYMEME. — C. REGULAR AND IRREGULAR — FIGURE AND
MOOD — FIRST AND SECOND FIGURES, 275
LECTURE XXI.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO EXTERNAL FORM. — THIRD AND FOURTH
FIGURES, 294
LECTURE XXII.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
ACCORDING TO EXTERNAL FORM. — C. REGULAR AND IR-
REGULAR. — FIGURE — REDUCTION, 306
LECTURE XXIII.
DOCTRINE OF REASONINGS. — SYLLOGISMS — THEIR DIVISIONS
. ACCORDING TO VALIDITY. — FALLACIES, ..... 321
LECTURE XXAY^
PAOB
PURE LQG^e.
PART If. METHODOLOGY. — SECTION I. METHOD IN GENERAL.—
SECTION II. METHOD IN SPECIAL, OR LOGICAL METHODOLr-
OGY. — I. DOCTRINE OF DEFINITION, . . • . . . . 335
LECTURE XXV.
METHODOLOGl.
LOGICAL METHODOLOGY. — 11. DOCTRINE OF DIVISION, . . 350
LECTURE XXVI.
LOGICAL METHODOLOGY, — III. DOCTRINE OF PROBATION, . . W.
LECTURE XXVII.
MODIFIED LOGIC.
PART I. MODIFIED STOICHEIOLOGY. — SECTION I. DOCTRINE OF
TRUTH AND ERROR. — TRUTH — ITS CHARACTER AND KINDS, 3W
LECTURE XXVIII.
MODIFIED STOICHEIOLOGY.
SECTION L DOCTRINE OF TRUTH AND ERROR. — SECTION II. ER-
ROR - JTS CAUSES AND REMEDIES. -^ A. GENERAL CIRCUM-
STANCES — SOCIETY, ,,...,.,,. 387
LECTURE XXIX.
ERROR -ITS CAUSESI AND REMEDIES, — A. GENERAL CIRCUM-
STANCES — SOCIETY. — B. AS IN POWERS OF COGNITION,
FEELING, ANP DESIR?. — L AFFECTIONS — PRECIPITANCY ^
SLOTH — POPE AJJD fEAJ^ — gELF-LOVE, . . , . . ,397
XIV CONTENTS.
LECTURE XXX.
PAOB
EKROR — ITS CAUSES AND REMEI>IES. — B. AS IN THE COGNI-
TIONS, FEELINGS, AND DESIRES. — 11. WEAKNESS AND DI&-
PROPORTIONED STRENGTH OF THE FACULTIES OF KNOWL-
EDGE, ........ 411
LECTURE- XXXI.
ERROR— ITS CAUSES AND REMEDIES. — C. LANGUAGE. — D. OB-
JECTS OF KNOWLEDGE, 432
LECTURE XXXII
MODIFIED METHODOLOGY.
SECTION I. OF THE ACQUISITION AND PERFECTING OF KNOWL-
EDGE. — L EXPERIENCE. — A. PERSONAL: — OBSERVATION —
INDUCTION AND ANALOGY, 44i
LECTURE XXXIII.
OF THE ACQUISITION AND PERFECTING OF KNOWLEDGE. — I.
EXPERIENCE. — B. FOREIGN : — ORAL TESTIMONY — ITS CRED-
IBILITY, ^77
LECTURE XXXIV.
OF THE ACQUISITION AND PERFECTING OF KNOWLEDGE. — I.
EXPERIENCE. — B. FOREIGN: RECORDED TESTIMONY AND
WRITINGS IN GENERAL. — II. SPECULATION K8
LECTURE XXXV.
OF THE ACQUISITION AND PERFECTING OF KNOWLEDGE. — III.
COMMUNICATION OF KNOWLEDGE. — A. INSTRUCTION —
ORAL AND WRITTEN. — B. CONFERENCE — DIALOGUE AND
DISPUTATION, 478
CONTENTS. XT-
APPENDIX.
PAOB
I. — THE CHARACTER AND COMPREHENSION OF LOGIC — A FRAG-
MENT, 495
II. — GENUS OF LOGIC, 4a8
HI. — DIVISIONS, VARIETIES, AND CONTENTS OF LOGIC, . . WI
IV — LAWS OF THOUGHT, . T S06
,V. — NEW ANALYTIC OF LOGICAL FORMS — GENERAL RESULTS
—FRAGMENTS.
I. — EXTKACT FROM PBOSPECTCS OF "ESSAY TOWARDS A NEW
ANALYTIC OF LOGICAL FORMS," 509
, II. — LOGIC, — ITS POSTULATES, 512
III. — QUANTIFICATION OF PREDICATE, — IMMEDIATE INFER-
ENCE,— CONVERSION, — OPPOSITION, .... 514
IV. — APPLICATION OF DOCTRINE OF QUANTIFIED PREDICATE
TO PROPOSITIONS, 52^
V. — APPLICATION OF DOCTRINE OF QUANTIFIED PREDICATE
TO SYLLOGISMS, . . 53tJ
VI. — OBJECTIONS TO THE DOCTRINE OF A QUANTIFIED PRED-
ICATE CONSIDERED, 53!il
VII. — HISTORICAL NOTICES OF DOCTRINE OF QUANTIFIED
PREDICATE, 546
VI. — CANONS OF SYLLOGISM; GENERAL HISTORICAL NOTICES
AND CRITICISM.
A. HISTORICAL NOTICES.
I. — FUNDAMENTAL LAWS OF SYLLOGISM — QUOTATIONS,
n. — FUNDAMENTAL LAWS OF SYLLOGISM — REFERENCES,
III. — ENUNCIATIONS OF THE HIGHER LAWS OF SYLLOGISM,
IV. — OBJECTIONS TO THE DICTUM DE OMNI ET NULLO,
V. — GENERAL LAWS OF SYLLOGISM IN VERSE,
VI. — SPECIAL LAWS OF SYLLOGISM IN VERSE,
559
575
570
578
578
579
B. CEITICISM.
I.— CRITICISM OF THE SPECIAL LAWS OP SYLLOGISM, . . 579
II. — LAWS OP SECOND FIGURE, .... . . 582
III. — author's supreme canons of CATEGORICAL SYLLO-
GISMS, 583
IV. — ULTRA-TOTAL QUANTIFICATION OF MIDDLE TERM, . 584
XVf CONTENTS.
VII. — INDUCTION AND EXAMPLE.
PASS
I. — QUOTATIOXS FKOM AUTHOKS, . .... . . 589
II. — MATERIAL INDUCTION, 597
Aim. — HYPOTHETICAL AND DISJUNCTIVE REASONING — IMMEDI
ATE INFERENCE.
I. —author's doctrine — FRAGMENTS, 598
II. — HISTORICAL notices, 612
U.. — SORITES, 619
X. - SYLLOGISM.
I. — 1T8 ENOUNCEMENT — ANALYTIC AND 8TNT^ETIC — ORDER
OF PREMISES.
(a) ENOUNCEMENT OF SYLLOGISM, .... 621
>-:. (b) ORDER OF PREMISES, 624
II. — FIGURE — UNFIGURED AND FIGURED SYLLOGISM.
(1803) (a) CONTRAST AND COMPARISON OF THE VARI-
OUS KINDS OF FORMAL SYLLOGISM — DIFFERENCE OF
> FIGURE ACCIDENTAL, ....... 626
(6) DOUBLE CONCLUSION IN SECOND AND THIRD FIG-
URES, . . . . . . . . . 627
III- — HISTORICAL NOTICES REGARDING FIGURE OF SYLLOGISM, 632
. „ IV. — SYLLOGISTIC MOODS.
I. — DIRECT AND INDIRECT MOODS, .... 658
II.— INDIRECT MOODS OF SECOND AND THIRD FIGURES, 663
III- — NEW MOODS — NOTES UPON TADLE OF SYLLOGISMS. 66.'>
XI. — LOGICAL NOTATION.
I. — Lambert's linear notation, ...... 6ff7
II. — NOTATION BY MAASS, 669
. Ill- — author's scheme of notation.
j no. I. linear, 670
^ NO. II. UNFIGURED AND FIOURBD SYLLOGISM, . . 6TJ
NO. III. FIGURPD SYLLOGISM — TABLE OF MOODS, . 678
LECTURES ON LOGIC.
LECTURE I *
ENTRODUCTION.
LOGIC— I. ITS DEFINITION.
Gentlemen : — We are now about to enter on the consideration
of one«of the most important branches of Men-
Logic proper,— mode tai Philosophy, — the science which is conver-
in which itsconsidera- ^^^^ ^^^^^ ^^^ j^^^^ ^^ Thought. But, before
tion ought to be con- ,
ducted. commencing the discussion, I would premise a
word in regard to the mode in which it ought
to be conducted, with a view to your information and improvemi-nt.
The great end which every instructor ought to-'
End of instruction. ° . , . . „ . .
ptopose in the communication oi a science, is, to
afford the student clear and distinct notions of its several parts, of
their relations to each other, and to the whole of which they are
the constituents. For unless he accomplish this, it is of compara-
tively little moment that his information be in itself either new or
important; for of what consequence are all the qualities of a doc-
trine, if that doctrine be not communicated? — and communicated
it is not, if it be not undei-stood.
But in the communication of a doctrine, the methods to be fol
lowed by an instructor who writes, and by an
Methods of written instructor who spealcs, are not the same. They
and oral instruction . „ . ,, ,.™
different ^^®' ^" ^^^*' ^^ ^ Certain extent, necessarily dii-
ferent : for, while the reader of the one can al-
ways be referred back or forward, can always compare one part, of a
* The first seven Lectares of the Metaphysical Course (Lectures on Metaphysics, pp.
1—90) were delivered hy Sir William Hamilton as a General Introdaction to the
Course of Logic proper. — Ed. ^
1
2 LOGIC. Lect. I.
hook \rith another, and can always meditate at leisure on each step
of the evolution ; the heai-er of the other, on the contraiy, must at
every moment be prepared, by what has preceded, to comprehend
at once what is to ensue. The oral instructor has thus a much more
arduous problem to solve, in accomplishing the end which he pro-
poses. For if, on the one hand, he avoid obscurity by communicat-
ing only what can easily be understood as isolated fragments, he is
intelligible only because he communicates nothing worth learning :
and if, on the other, he be unintelligible in proportion as his doc-
trine is concatenated and systematic, he equally fails in his attempt ;
for as, in the one case, there is nothing to teach, so, in the other,
there is nothing taught. It is, therefore, evident, that the oral in-
structor must accommodate his mode of teaching to the circum-
stances under which he acts. He must endeavor to make his audi-
ence fully understand each step of his movement before another is
attempted ; and he must prepare them for details by a previous sur-
vey of generals. In short, what follows should always be seen to
evolve itself out of what precedes. It is in consequence of this
condition of oral instruction, that, where^ the development of a sys-
tematic doctrine is attempted in a course of Lee-
Use of Text-book in t^j-Q^^ jt is usual for the lecturer to facilitate the
a systematic course of , , , . ., i , • -.fi i -i • •
j^j.jjjj.^ labor to his pupils and himself, by exhibiting in
a Manual or Text-book the order of his doctrine
and a summary of its contents. As I have not been able to prepare
this useful subsidiary, I shall endeavor, as far as possible, to supply
its want. I shall, in the first place, endeavor always to present you
with a general statement of every doctrine to
u or 8 met o ^^^ explained, before descending to the details
of explanation ; and in order that you may be
insured in distincter and more comprehensive notions, I shall, where
it is possible, comprise the general statements in Propositions ot
Paragraphs, which I shall slowly dictate to you, in order that they
may be fully taken down in writing. This being done, I shall pro-
ceed to analyze these propositions or paragraphs, and to explain
their clauses in detail. This, I may observe, is the method followed
in those countries where instruction by prelection is turned to the
best account; — it is the one prevalent on the Continent, more es-
pecially in the universities of Germany and Holland.
In pursuance of this plan, I at once commence by giving you,
as the first proposition or paragraph, the following. I may notice,
however, by parenthesis, that, as we may have sometimes occasion
to refer articulately to these propositions, it would be proper for
you to distinguish them by «ign and number.
Lect. I. LOGIC. "8
The first paragraph, then, is this :
^ I. A System of Logical Instruction consists of Two Parts,
— 1°, Of an Introduction to the science;
Jrof'LogllTonsrt's; 2°, Of a Body of Doctrine constituting the
Science itself.
Thiese, of course, are to be considered in their order.
^ II. The Introduction to Logic should afford answere to the
following questions: i. What is Logic? ii.
Par. n The Intro- ^^^^ j^ j^^ y^j^^^ ^ jj._ ^^^^ ^^.^ .^^ j)j^.j^_
duction to Iioglc.
ions ? iv. What is its History ? and, v.
What is its Bibliography, that is, what are the best books upon
the subject?
In regard to the first of these questions, it is evident that its
answer is given in a definition of Logic. I therefore dictate to
you the third paragraph. ,
Par. m. I. Defini-
tion of liOgic.
•fill. What is Logic? Answer — Logic
is the Science of the Laws of Thought as
Thought.
This definition, however, cannot be understood without an ar-
ticulate exposition of its several parts. I there-
Explication. ^ ...
fore proceed to this analysis and explanation,
and shall consider it under the three following heads. In the first,
I shall consider the meaning, and history, and synonyms of the
word Logic. In the second, I shall consider the Genus of Logic,
that is, explain why it is defined as a Science. In the third, I shall
consider the Object-matter of Logic, that is, explain to you what
is meant by saying, that it is conversant about the Laws of Thought
as Thought.
First, then, in regard to the significance of the word. Logic, you
are aware, is a Greek word, XoytK?;; and Xoytfo^,
1. The word I^g-ic — i-i r, / /^\ /t-i
nice ypafL^aTLKi), prp-opixr], TrovqTUcrj, ocoAeicTiKiy, 1 neeu
hardly tell you, is an adjective, one or other of
the substantives iTna-rrnvr}, science, rix^^, (^rt, or Trpayfiareia, Study, or
rather matter of study, being understood. The term XoyiKt], in this
special signification, and as distinctly marking out a particular sci-
ence, is not, so old as the constitution of that science itself Aris-
totle did not designate by the term AoytKt;, the science whose doc-
4 LOGIC. Lect. t
trine he first fully developed. He uses, indeed, the adjective \oyucos
in various combinations with other substantives.
Thus I find in his Physics, Xoyucq airopw^ — in
his Rhetoric, AoyiKai Sva^epeiai,^ — in his Jifetapht/Sics, XoyiKas airoheCi-
tts,^ — in his Posterior Analytics, hia XoytKa* — in his Topics, Xoyi-
Kov -n-pofiXrjfia.^ He, likewise, not unfreqiiently makes use of the
adverb Xoyi/cws.^ By whom the term XoyiK-rj was first applied, as the
word expressive of the science, does not appear. Boethius, W'ho
flourished at the close of the fifth and commencement of the sixth
<tentui-y, says, in his Commentary on the Topics of Cicero^ that the
name of Logic was first given by the ancient
enpa e ics. Peripatetics. In the works of Alexander of Aph-
Alexander of Aph- rodisias, the oldest commentator we possess on
the works of Aristotle (he flourished towards
the end of the second century), the term Aoyoci;, both absolutely
and in combination with TrpayfiareLa, etc., is frequently employed ; '
and the word is familiar in the writings of all the subsequent Aris-
totelians. Previously, however, to Alexander, it is evident that
XoviKM had become a common designation of the
Cicero. . .
science; for it is once and again thus applied
by Cicero.® So much for the history of the word JLogic, in so far
as regards its introduction and earlier employment. We have now
to consider its derivation and meaning.
It is derived from Ao'yos, and it had primarily
(b) Its derivation and the Same latitude and variety of signification as
"^oid meaning of its original. What then did Xoyo9 signify ? In
xiiyos. Greek this word had a twofold meaning. It
denoted both thought and its expression ; it was
equivalent both to the ratio and to the oratio of the Latins. Tlie
» B. iii. c. 3. 'Exsi 5' airopiay \oyiirfiv. * E. g., Anal. Poxt., i. 21, 32 j Phys. viii. 8;
" Dubitationem quae non e rerum singularium -Me/apA., vi. 4, 17; xi. 1. — Ed.
(pby8icarum)contemplatione, sed e ratiocina- ^ ^-i- sub init. — ^o.
tione sola orta est." Waitz, ad Arist. Org., ^ See, especially, bis commentary on the
vol. ii. p 354. Logical and diaUctical reason- P^'°'" Analytics, f. 2 (Scholia, ed, Brandis, p.
ing in Aristotle mean the same thing, — viz., 1*1)' where he divides v ^oyitcfi re koI av\-
reasoniug founded only on general principles A.<>7«errw^ itpaynartia into four branches,
of probability, not on necessary truths or on airoSfi/cTi/cVj, 8ja\€JCTtKii, irfipaffTiK-^, and
special experiences. — Ed. ffOi(>UTTiK-fi. Here Logic is used in a wiri<T
5 This expression occurs not in the Rhetoric, *«*«e **>*« **>® adjective and adverb bear ii.
bnt in the Metaphysics, B. i!i. (iv.) c. 3, and B. Aristotle, while the cognate term dialectic re-
xiii. (xiv.)c. 1. In ihe Rhetoric we find the tains its original signification. — Ed.
expression KoytKol ffv?<\oyt(rfioi B. i c. 1. ^ ^®® ^' Finxbus, i. 7; Tusc. Qaast., iv. 14.
— Ed. Cicero probably borrowed this use of the
n'f n rr . • term from the Stoics, to who.oe founder, Zcno,
Cf. De Gener. Antm., , .. „ .^ .. ■ ■ r n
Laertius (vii. 39) ascribes the ongm of tlw
division of Philosophy into 'Logic, Physloi,
and Ethics, sometimes erroneously mttribiit«d
to Plato. — Ed.
.■»B.
xiii.
. (xiv
.)c.
1
ii. 8.-
-Ed.
4B.
i.e.
24 -
-Ed.
SB.
y. c.
L —
Ed-
tEOT.L LOGIC. 6
Greeks, in order to obviate the ambiguity thus arising from the
confusion of two different things under one expression, were com-
pelled to add a diflferential epithet to the common term. Aristo-
tle, to contradistinguish Xoyos, meaning thought^
How expressed by ^^^^ Xoyos, meaning speech, calls the former rov
Aristotle. ^ ^ ^ .t. i*?
£o-(j, — Tov ev TTj i/^xW' — ^'^^^ Within^ — that %n the
ffiind/ and the latter, t6v tftu, — that without} The same distinc-
tion came subsequently to be expressed by the
Aoyos cvSta-Jeros, for thought, the verbum mentis ;
and by Xoyos irpotftopiKo^, for language, the verbum oris? It was nec-
essary to give you this account of the ambiguity qf the word Xoyos, '
because the same passed into its derivative XoyuciJ ; and it also was
necessary that you should be made aware of the ambiguity in the
name of the science, because this again exerted an influence on the
views adopted in regard to the object-matter of the science.
But what, it may be asked, was the appellation of the science
before it had obtained the name of Logic f for,
Appellations of the gg j jj^ye g^j^^ ^jj^ doctriue had been discrimi-
ecience afterwards , , i • i /« •
called Logic. nated, and even carried to a very high perfection,
before it received the designation by which it is
now generally known. The most ancient name for what was sub-
sequently denominated Logic^ was Dialectic. But this must be
understood with certain limitations. By Plato, the term dialectic is
frequently employed to mark out a particular section of philosophy.
But this section is, with Plato, not coextensive with the domain of
Logic ; it includes, indeed. Logic, but it does not exclude Metaphysic,
for it is conversant not only about the form, but about the matter
of our knowledge. (The meaning of these expressions you are
soon to learn.)
This word, StoXeKn/c^ (tcj^vt/, or iTrurr-^fir], or Trpay/iaTCto, being
understood) is derived, you are aware, from
t (KTiHTj— I sey- SiaXeyco'^ai, to hold conversation or discourse
inology. '
together ; dialectic, therefore, literally signifies,
of a conversation, colloquy, controversy, dispute. But Plato, who
defined thought an internal discourse of the soul with itself,^ and
who explained to StoX^yccr^ai by the ambiguous expression tw Xoyul
1 jlnaZ. Port., 1. 10. — Ed. originated with the Stoics. See Wytten-
2 E. g , Philo, Be Vita Mosis, p. 672, edit, bach's note on Plutarch's Moralia, p. 44 A
I'liiis. 1640; Plutarch, Philos. esse cumprincipi- (torn. vi. pars 1, p. 378, edit. Oxon, 1810).—
i>i/s. c. 2 (vol. ii. p. 777, C, ed. Francof., 1620); Ed.
Sextus Empiricus, Pyrrh. Hyp., i. 65; Simpli- 8 Fishaber, p. 10. [Lehrbuehder LogikfEmM-
vinf. Ta Categ. Arist., p. 7; DamSLScenvs, Fiit. tung. See necetetus p. ISQ. Sophista, p- 266
•MiUoii., ii. 21. The expressions probably — Ed.]
LOGIC. Lect. L
Xprja-Sai,^ did not certainly do violence either to the Greek lan-
guage or to his own opinions, in giving the
seo tie term a- jj^mc of dialectic to the process, not merely of
leetic by riato. '^ ^ • ■, i
logical inference, but of metaphysical specula-
tion. In our own times, the Platonic signification of the word
has been revived, and Hegel has applied it, in
^ ^^ ■ even a more restricted meaning, to metaphysical
speculation alone.^ But if Plato employed the term Dialectic
to denote more than Logic, Aristotle employed
Aristotle's employ- j^. ^^ denote Icss. With him, Dialectic is n»^t
ment of Dialectic. r -i • i • •
a term for the pure science, or the science in
general, but for a particular and an applied part. It means
merely the Logic of Probable Matter, and is thus convertible
with what he otherwise denominates Topics (tottoo/).' This, I
may observe, has been very generally misunderstood, and it i.s
commonly supposed that Aristotle uses the term Dialectic in two
meanings, — in one meaning for the science of Logic in general,
in another for the Logic of Probabilities. This is, however, a
mistake. There is, in fact, only a single passage in his writings,
on the ground of which it can possibly be maintained that he ever
employs Dialectic in the more extensive meaning. This is in his
Rhetoric i. 1 '* but the passage is not stringent, and Dialectic may
there be plausibly interpreted in the more limited signification.
But at any rate it is of no authority, for it is an evident interpola-
tion, — a mere gloss which has crept in from the margin into the
text.* Thus it appears that Aiistotle possessed no single term by
which to designate the general science of which he was the prin-
cipal author and finisher. Analytic^ and Apo-
. "" ^"'' ' ''" "'^' deictic with Topic (equivalent to Dialectic^
and including Sophistic), were so many special
names by which he denoted particular parts, or particular applica
tions of Logic. I say nothing of the vacillating and various em-
ployment of the terms Logic and Dialectic by the Stoics, Epicu-
reans, anfl. other ancient schools of philosophy; ajid now proceed
to explain to you the second head of the definition, — viz., the
Genus, — class, of Logic, which I gave as Science.
It was a point long keenly mooted by the old logicians, whether
1 I. Alcih., p. 129. Sri. Tb Se tiaXeyt^a^at ■* Ilepl lik cvWoyiafiov ifiolws Sltoitos
Kol TV X6ja> -xpriff^ai toutoV itov KdKfts; ttjs hidKtKTiKris iffTtv Ihfti' ^ outtjs S\»ji ^
AA rioci; 76. Cf. Gassendi, io?/ca, frooem. fxipovs riv6s. — Y.Xi.
Opera, t. i. p. 32. — Ed. r, g,,^ jjaiforeus. [R. Balforei Commentarius in
2 See Encyklopddie, § 81. - Eo. ^ Organum Logieum Aristotelis, Burdigala. 1618.
S Topica, i. 1. AtaA€/cT.Kj)s 5e ffvWoyiff- qu. h. ^ 3^ p. jj. Muretus, in his version.
«J)s & i^ fySd^yu cvWoyi(6ixtyos. — Ed. omits this passage as an interpolation. — Ed.J
Lect. I. LOGIC. 7
Logic were a science, or an ai't, or neither, or both ; and if a science,
• whether a science practical, or a science specu-
2. Logic— Its Genus lative, or at once speculative and practical.
— whether Science or t , -1-.1 • • -, • • 1
^^ Jrlato and the Jrlatonists Viewed it as a science;'
but with them Dialectic, as I have noticed,
was coextensive with the Logic and Metaphysics of the Peripatetics
taken together. By Aristotle himself Logic is not defined. The
Greek Aristotelians, and many philosophers since the revival of
letters, deny it to be either science or art.^ The Stoics, in general,
viewed it as a science ;^ and the same was done by the Arabian and
Latin schoolmen-* In more modern times, however, many Aris-
totelians, all the Ramists, and a majority of the Cartesians, main-
tained it to be an ai't;* but a considerable party were found who
defined it as both art and science.^ In Germany, since the time of
Leibnitz, Logic has been almost universally regarded as a science.
The controversy which has been waged on this
The question futile. . . ,. ., • 1
point IS perhaps one 01 the most futile in the
history of speculation. In so far as Logic is concerned, the decis-
ion of the question is not of the very smallest import. It was not
in consequence of any diversity of opinion in regard to the scope
and nature of this doctrine, that philosophers disputed by what
name it should be called. The controversy was, in fact, only about
what was properly an art, and what was properly a science ; and as
men attached one meaning or another to these terms, so did they
affirm Logic to be an art, or a science, or both, or neither. I should
not, in fact, have thought it necessary to say anything on this head,
were it not to guard you against some mistakes of the respectable
author, whose work on Logic I have recommended to your atten-
tion,— I mean Dr. Whately. In the opening sentence of his
Elements, it is said : " Logic, in the most exten-
Whately quoted. . 1 • , ,
sive sense which the name can with propriety
be made to bear, may be considered as the Science, and also the
Art of Reasoning. It investigates the principles on which argumen-
tation is conducted, and furnishes rules to secure the mind from
1 [Camerarius, Dwputoft'ones PAi/o5opWc«, p. 1. § 1. subs. 4, tt seg., p. 8, ed. 1711. — Ed.]
30.] [Pars i. qu. 3, ed. Farisiis, 1630. See Gerard John Vossius, De Nat. Artium, sive de
also Qu. 4, p. 44. — Ed.] I^gica^ c. vi ]
2 [See Themistius, In Anal. Post., 1. i. c. 24, 3 [See Laertius, In Vita Zenonis, 1. vii.] [J 62.
[Opera, p. 6, Venice, 1554. — Ed.] Ammonius Ed.]
Hermiae, iii Ca«<'g-., Prasf. [p. 3, ed. Aid. 1503. * ro * n. j- . r\ t iii •.
^ „. ,.f^„^„,„ * [Scotus, Prcedicamenta, Qu. i. Albertus
— Ed.] Simplichis. /rt Oiifg-., Praef. [§ 25, p. „ r r, r, ..,■ >.•,,. i,
^ ., ,, , „ „ , ., Magnus, In De Praduabtlibus, c. 1.]
5, ed. Basilese. 1551. — Ed ] Zabarella, Z»« ^ ' ' '
Natura Logicee, [1. i. c. 5, et seg. — Ed.] Smi- ^ [Ramus, Instit. Dialect., 1. i. c. 1. Bur-
glecius, Logica, Disp. ii. qu. 4, [p. 69, ed. Ox- gersdicius, Instit. Log., 1. i. c. 1, [§ 4. — Ed.]
onii, 1658. — Ed.] Logica Conimbricensis, [Tract 6 • See Smiglecius, as abore. — "Ed.
8 ' LOGIC. Lect. 1.
error in its deductions. Its most appropriate office, however, is
that of instituting an analysis of the process of the mind in rescu-
ing; and in this point of view it is, as has been stated, strictly a
science; while mentioned in reference to the practical rules above
mentioned, it may be called the art of reasoning. This distinction,
as will hereafter appear, has been overlooked, or not clearly pointed
out, by most writers on the subject; Logic having been in general
regarded as merely an art, and its claim to hold a place among the
sciences having been expressly denied."
All this is, from first to last, erroneous. In the first place, it is
erroneous in what it says of the opinion prev-
Criticized. , i -i i . n i
alent among philosophers, in regard to the genus
of Logic. Logic was not, as is asserted, in general regarded as an
art, and its claim to hold a place among the sciences expressly
denied. The contrary would have been correct; for the immense
majority of logicians, ancient and modem, have regarded Logic as
a science, and expressly denied it to be an art. In the second place,
supposing Dr. Whately's acceptation of the terms art and science
to be correct, there is not a previous logician who would have
dreamt of denying that, on such an acceptation, Logic was both a
science and an art. But, in the third place, the discrimination
itself of art and science is wrong. Dr. Whately considers science
to be any knowledge viewed absolutely, and not in relation to praC"
tice, — a signification in which every art would, in its doctrinal
part, be a science ; and he defines art to be the application of
knowledge to practice, in which sense Ethics, Politics, Religion,
and all practical sciences, would be arts. The distinction of arts
and sciences is thus wrong.^ But, in the fourth place, were the
distinction correct, it would be of no value, for it would distinguish
nothing, since art and science would mark out no real difierence
between the various branches of knowledge, but only different
points of view under which the same branch might be contemplated
by us, — each being in different relations at once a science and an
art. In fact, Dr. Whately confuses the distinction of science theo-
retical and science practical with the distinction of science and art.
I am well aware that it would be no easy matter to give a general
definition of science, as contradistinguished from art, and of art, as
contradistinguished from science ; but if the words themselves can-
not validly be discriminated, it would be absurd to attempt to dis-
criminate anything by them. When I, therefore, define Logic by
the genus science^ I do not attempt to give it more than the general
denomination of a branch of knowledge ; for I reserve the discrimi-
I Compare Lectures on Metaphysics, p. 81 et seq. — Ed.
Lk.CT. I. LOGIC. 9
nation of its peculiar character to the differential quality afforded
by its object-matter. You will find, when we have discussed the
third head of the definition, that Logic is not only a science, but a
demonstrative or apodictic science ; but so to have defined it, would
have been tautological ; for a science conversant about laws is con-
versant about necessary mattei-, and a science conversant about
necessary matter is demonstrative.
I proceed, therefore, to the third and last head of the defini-
tion,— to explain to you what is meant by the
^^' ^ °^ object^matter of Logic, — viz., the Laws of
Thought as Thought. The consideration ot
this head naturally divides itself into three questions : 1, What is
Thought? 2, What is Thought as Thought? 3, What are the Laws
of Thought as Thought ?
In the first place, then, in saying that Logic is conversant about
Thought, we mean to say that it is conversant
(a) Thought, — what. , . , . , ,i i m.
about thought strictly so called. The term
thought is used in two significations of different extent. In the
wider meaning, it denotes every cognitive act
In its wider and nar. ^^atcvcr ; by somc philosophers, as Descartes
rower meaning. -,,•-,••% ■ •
and his disciples, it is even used for every mental
modification of which we are conscious, and thus includes the Feel-
ings, the Volitions, and the Desires.' In the more limited meaning,
it denotes only the acts of the Understanding properly so called,
that is, of the Faculty of Comparison, or that which is distinguished
as the Elaborative or Discursive Faculty.^ It is in this more re-
stricted signification that thought is said to be
Objects that lie be- ^^xe object-matter of Logic. Thus Logic does
yond the sphere of • t i i t • i i , ,
j^^^.j. not consider the laws which regulate the other
powers of mind. It takes no immediate account
of the faculties by which we acquire the rude .materials of knowU
edge; it supposes these materials in possession, and considers only
the manner of their elaboration. Jt takes no account, at least in
the department of Pure Logic, of Memory and Imagination, or of
the blind laws of Association, but confines its attention to connec-
tions regulated by the laws of intelligence. Finally, it does not
consider the laws themselves of Intelligence as given in the Regu-
lative Faculty, — Intelligence, - — Common Sense ; for in that faculty
these laws are data, facts, ultimate and, consequently, inconceivable ;
1 Descartes, Prindpia, p. i. i 9. " Cogita- intelligere, velle, imaginari, sed etiam sentire.
tionis nomine intelligo ilia omnia quas nobis idem est hie quod cogitare." — Ed.
conseiis in nobis fiunt, quatenus eorum in 2 See Lectures on Mttaphysics, lect. xxxiv.
nobis conscieutia est. Atque ita non modo p. 463. — Ed.
2
10 LOGIC. Lect. L
but whatever transcends the sphere of the conceivable, transcends
the sphere of Logic,
Such are the functions about which Logic is not conversant, and
such, in the limited signification of the word, are the acts which are
not denominated Thought. We have hitherto found what thought
is not ; we must now endeavor to determine generally what it is.
The contemplation of the world presents to our subsidiary facul-
ties a multitude of objects. These objects are
oug proper. ^^^ ^^^^ materials submitted to elaboration by a
higher and self-active faculty, which operates upon them in obedi-
ence to certain laws, and in conformity to certain ends. The opera-
tion of this faculty is Thought. All thought is a comparison, a
recognition of similarity or difference ; a conjunction or disjunc-
tion ; — in other words, a synthesis or analysis of its objects. In
Conception, that is, in the formation of concepts (or general notions),
it compares, disjoins, or conjoins attributes; in an act of Judgment,
it compares, disjoins, or conjoins concepts;- in Reasoning, it com-
pares, disjoins, or conjoins judgments. In each step of this process
there is one essential element ; to think, to compare, to conjoin, or
disjoin, it is necessary to recognize one thing thi-ough or under
another; and therefore, in defining Thought proper, we may either
define it as an act of Comparison, or as a recognition of one notion
as in or under another. It is in performing this act of thinking a
thing under a general notion, that we are said to understand or
comprehend it. For example : an object is presented, say a book ;
this object determines an impression, and I am even conscious of the
impression, but without recognizing to myself what the thing is;
in that case, there is only a perception, and not properly a thought.
But suppose I do recognize it for what it is, in other words, com-
pare it with, and reduce it under, a certain concept, class, or com-
plement of attributes, which I call book; in that case, there is more
than a perception, — there is a thought.
All this will, however, be fully, explained to you in the sequel ; at
present I only attempt to give you a rude notion of what thinking
is, to the end that you may be able vaguely to comprehend the lim-
itation of Logic to a certain department of our cognitive functions,
and what is meant by saying that Logic is a science of thought.
But Thought simply is still too undetermined; the proper object
of Logic is something still more definite ; it is
-what"*^ *^ °"^ "^*' t^<^"ght in general, but thought considered
merely as thought, of which this sc^icnce takes
cognizance. This expression requires explanation ; we come there-
Lect. L logic. 11
fore to the second question, — What is meant by Thought as
Thought ?
To answer this question, let us remember what has just been said
of the act constitutive of thought, — viz., that it is the recognition
of a thing as coming under a concept ; in other words, the marking
an object by an attribute or attributes previously known as common
to sundry objects, and to which we have accordingly given a general
name. " In this process we are able, by abstraction, to distinguish
from each other, — 1°, The object thought of;
,„ . and, 2°, The kind and manner of thinking it.
Let us, employing the old and established tech^
nical expressions, call the first of these the matter, the second the
form, of tlie thought. For example, when I think that the book
before me is a folio, the matter of this thought is book and folio ;
the form of it is a judgment. Now, it is abundantly evident that
this analysis of thought into two phases or sides is only the work
of a scientific discrimination and contrast ; for as, on the one hand,
the matter of which we think is only cogitable through a certain
form, so, on the other, the form under which we think cannot be-
realized in consciousness, unless in actual application to an object."*
Now, when I said that Logic was conversant
Logic properly con- ^^^^^ thought Considered merely as thought, I
versaut only with the , , i t • •
Form of Thought meant simply to say, that Logic is conversant
with the form of thought, to the exclusion of
the matter. This being understood, I now proceed to show how
Logic only proposes — how Logic only can propose — the form of
thought for its object of consideration. It is- indeed true, that this
limitation of Logic to the form of thought has not always been
kept steadily in view by logicians; that it is only gradually that
proper views of the science have been speculatively adopted, and
still more gradually that they have been carried practically into
eflTect, insomuch that to the present^ hour, as I shall hereafter show
you, there are sundry doctrines still taught as logical, which, as
relative to the matter of thought, are in fact foreign to the science
of its form.
"But although it is impossible to show by the history of the
science, that Logic is conversant with the form,
This shown by a con- ^o the cxclusiou of the matter, of thought ; this
sideration of the na- ■■ , ,• p , •^ t i -i
ture and conditions of Can, however, be Satisfactorily done by a consid-
the thing itself. eration of the nature and conditions of the
thing itself For, if it be maintained that Logic
takes not merely the form, but the matter of thought into account
1 Esser, Logik, i, 3, p. 4, 2d edit. MUnster, 1830. — Ed.
12 LOGIC. Lect. I
(the matter, you will recollect, is a collective expression for the
several objects about which thought is conversant), in tiiat case,
Logic must either consider all those objects without distinction, or
make a selection of some alone. Now the former of these alterna-
tives is manifestly impossible ; for if it were required that Logic
should comprise a full discussion of all cogitable objects, — in other
words, if Logic must draw within its sphere all other sciences, and
thus constitute itself iu lact the one universal science, -^ every one at
once perceives the absurdity of the requisition, and the impossibility
of its fulfilment. But is the second alternative more reasonable?
Can it be proposed to Logic to take cognizance of certain objects
of thought to the exclusion of others? On this supposition, it
nmst be shown why Logic should consider this particular object,
and not also that; but as none but an arbitrary answer — that is,
no answer at all — can be given to this interrogation, the absurdity
of this alternative is no less manifest than that of the other. The
particular objects, or the matter of thought, being thus excluded,
the form of human thought alone remains as the object-matter of
our science ; in other words. Logic has only to do with thinking as
thinking, and has no, at least no immediate, concernment with that
which is thought about. Logic thus obtains, in common parlance,
the appellation of a fonnal science, not indeed in the sense as if
Logic had only a form and not an object, but simply because the
form of human thought is the object of Logic; so that the title
formal science is properly only an abbreviated expression." *
I proceed now to the question under this head, — viz.. What is
meant by the Laws of Thought as Thought ? in
n^*^^ u.'^ -^u^^ u? Other words. What is meant by the Formal Laws
Thought as ThouRht. •'
of Thought ?
We have already limited the object of Logic to the form of
thought. But there is still required a last and final limitation ; for
this form contains more than Logic can legitimately consider. " Hu-
man thought, regarded merely in its formal relation, may be consid-
ered in a twofold point of view ; for, on the one hand, it is either
known to us merely from experience or observation, —we are
merely aware of its phenomena historically or empirically, or, on the
other, by a reflective speculation, — by analysis and abstraction, we
seek out and discriminate in the manifestations of thought what is
contained of necessary and universal. The empirical or historical
consideration of our thinking faculty does not belong to Logic, but
to the PhaBuomenology of Mind, — to Psychology. The empirical
I Esser, Lo^k, i 3, pp. 5, 6. Cf. Krng, DenkUhre oder Logik, ( 8, p. 17 tt seq., 2d edit. 1819
— Ed.
Lect. I. LOGIC. 13
observation of the phenomena necessarily, indeed, precedes their
speculative analysis. But, notwithstanding this. Logic possesses a
peculiar province of its own, and constitutes an independent and
exclusive science. For where our empirical consideration of the
mind terminates, there our speculative consideration commences;
the necessary elements which the latter secures from the contingent
materials of observation, — these are what constitute the laws of
thought as thought."* >
1 Cf. Eeser, LogUc, § 4, pp. 6, 7. — Bd
LECTURE II.
INTRODUCTION.
LOGIC — I. Its definition— historical notices of opinions
REGARDING ITS OBJECT AND DOMAIN — IL ITS UTILITY.
In my last Lecture I commenced the consideration of Logic, —
of Losric properly so denominated, — a science
Recapitulation. „ , , . . /. , • , ^
for the cultivation oi which every European
university has provided a special chair, but which, in this country, in
consequence of the misconceptions which have latterly arisen in re-
gard to its nature and its end, has been very generally superseded ;
insomuch that, for a considerable period, the chairs of Logic in our
Scottish universities have in fact tauglit almost everything except
the doctrine which they were established to teach. After some pre-
cursory observations in regard to the mode of communication which
I should follow in my Lectures on this subject, I entered on the treat-
ment of the science itself, and stated to you that a systematic view
of Logic would consist of two parts, the one being an Introduction
to the doctrine, the other a body of the Doctrine itself. In the in-
troduction vieve considered certain preparatory points, necessary to
be understood before entering on the discussion of the science itself;
and I stated that these preparatory points were, in relation to our
science, exhausted in five questions and their answers — 1°, What is
Logic ? 2°, What is its value ? 3°, How is it distributed ? 4°, What
is its history? 5°, What are its subsidiaries?
I then pi'oceeded to the consideration of the first of these ques-
tions ; and as the answer to the question, — what is Logic, — is given
in its definition, I defined Logic to be the science conversant about
the laws of thought considered merely as thought ; warning you,
however, that this definition could only be understood after an artic-
ulate explanation of its contents. Now this definition, I showed
you, naturally fell into three parts, and each of these parts it be-
hooved to consider and illustrate by itself The first was the word
significant of the thing defined, — Logic. The second was the
genus by which Logic was defined, — science. The third was the
Lect. II. LOGIC. 15
object-matter constituting the differential quality of Logic, — the
laws of thought as thought. Each of these I considered iu its order,
I, first of all, explained the original meaning of the term Logic, and
gave you a brief history of its application. I then stated what was
necessary, in regard to the genus, — science ; and, lastly, what is of
principal importance, I endeavored to make you vaguely aware of
that which you cannot as yet be supposed competent distinctly to
comprehend ; I mean the peculiar character of the object, — object-
matter, — about which Logic is conversant. The object of Logic,
as stated in the definition, is the laws of thought as thought. This
required an- articulate explanation ; and such an explanation I en-
deavored to afford you under three distinct heads ; expounding,
1°, What was meant by thought; 2°, What was meant by thought
as thought ; 3°, What was meant by the laws of thought as thought.
In reference to the first head, I stated that Logic is conversant
about thought taken in its stricter signification, that is, about thought
considered as the operation of the Understanding Proper, or of that
faculty which I distinguished as the Elaborative or Discursive, —
the Faculty of Relations, or Comparison. I attempted to make you
vaguely apprehend what is the essential characteristic of thought,
— viz., the comprehension of a thing under a general notion or attri-
bute. For such a comprehension enters into every act of the dis-
cursive faculty, in its different gradations of Conception, Judgment,
and Reasoning. But by s.iying that Logic is convers.int about
thought proper, Logic is not yet discriminated as a peculiar science,
for there are many sciences, likewise, inter alia, convei'sant about the
operations and objects of the Elaborative Faculty. There is re-
quired a further determination of its object-matter. This is done
by the limitation, that Logic is conversant not merely about thought,
but about thought as thought. The explanation of this constituted
the second head of our exposition of the object-matter. Thought, I
showed, could be viewed, by an analytic abstraction, on two sides
or phases. We could either consider the object thought, or the
manner of thinking it ; in other words, we could scientifically dis-
tinguish from each other the matter and the form of thought. Not
that the matter and form have any separate existence ; no object
being cogitable except under some form of thought, and no form of
thought having any existence in consciousness except some object
be thought under it. This, however, formed no impediment to our
analysis of these elements, through a mental abstraction. This is in
fact only one of a thousand similar abstractions we are in the habit
of making; and if such were impossible, all human science would
be impossible. For example : extension is only presented to sense,
16 LOGIC. Lect. U.
under some modification of color, and even imagination cannot rep-
resent extension except as colored. We may view it in phantasy
as black or white, as translucent or opaque ; but represent it we can-
not, except either under some positive variety of light, or under the
negation of light, which is darkness. But, psychologically consid-
ered, darkness or blackness is as much a color, that is, a positive
sensation, as whiteness or redness ; and thus we cannot image to
ourselves aught extended, not even space itself, out of relation to
color. But is this inability even to imagine extension, apait from
some color, any hinderance to our considering it scientifically apart
from all color ? Not in the smallest ; nor do Mathematics and the
other sciences find any difficulty in treating of extension, without
even a single reference to this condition of its actual manifestation.
The case of Logic is precisely the same. Logic considere the form
apart from the matter of thought ; and it is able to do this without
any trouble ; for though the form is only an actual phenomenon
when applied to some matter, — object, — yet, as it is not necessa-
rily astiicted to any object, we can always consider it abstract from
all objects ; in other words, from all matter. For as the mathema-
tician, who cannot construct his diagrams, either to sense or to im-
agination, apart from some particular color, is still able to consider
the properties of extension apart from all color ; so the logician,
though he cannot concretely represent the forms of thought except
in examples of some particular matter, is still able to consider the
properties of these forms apart from all matter. The possibility be-
ing thus apparent of a consideration of the form abstractly from
the matter of thought, I showed you that such an abstraction was
necessary. The objects (the matter) of thought are infinite; no
one science can embrace them all, and therefore, to suppose Logic
conversant about the matter of thought in general, is to say that
Logic is another name for thQ encyclopaedia — the omne scibile —
of human knowledge. The absurdity of this supposition is appar-
ent. But if it be impossible for Logic to treat of all the objects
of thought, it cannot be supposed that it treats of any ; for no rea-'
son can be given why it should limit its consideration to some, to the
exclusion of others. As Logic cannot, therefore, possibly include all
objects, and as it cannot possibly be shown why it should include
only some, it follows that it must exclude from its domain the con-
sideration of the matter of thought altogether ; and as, apart from
the matter of thought, there only remains the form, it follows that
Logic, as a special science of thought, must be viewed as convei-sant
exclusively about the form of thought.
But the limitation of the object-matter of Logic to the form of
Lkct. II. LOGIC. .37
thought (and the expression form of thought is convertible with
the expression thought as thought), is not yet
(c) The ws o enousrh to discriminate its province from that of
Thought «8 Thought. ^, ^ . f T> ^:^ 41, T? •
other sciences; tor Psychology, or the xLmpir-
ical Science of Mind, is likewise, among the other mental phaenom-
ena, conversant about the pbsenomena of formal thought. A still
further limitation is therefore requisite ; and this is given in say-
ing that Logic is the science not merely of Thought as Thought,
but of the Laws of Thought as Thought. It is this determination
which affords the proximate and peculiar difference of Logic, in
contradistinction from all other sciences; and the explanation of its
meaning constituted the third head of illustration, which the object-
matter in the definition demanded.
The phaenomena of the formal, or subjective phases of thought,
are of two kinds. They are either such as are
The phaenomena of contingent, that is, such as may or may not ap-
formal thought are of. , , ^i ^ •
. .. _, ^. ^ pear ; or they are such as are necessary, that ls,
two kinds— contingent r t j j ' i
and necessary. such as cannot but appear. These two classes-
of phaenomena are, however, only manifested in
conjunction; they are not discriminated in the actual operations of
thought; and it requires a speculative analysis to separate them
into their several classes. In so far as these phaenomena are con-
sidered merely as phaenomena, that is, in so far as philosophy is
merely observant of them as manifestations in general, they belong
to the science of Empirical or Historical Psychology. But when
philosophy, by a reflective abstraction, analyzes the necessary from
the contingent forms of thought, there results a science, which is
distinguished from all others by taking for its object-matter the
former of these classes ; and this science is Logic. Logic, there-
fore, is at last fully and finally defined as the science of the neces-
sary forms of thought. Here terminated our last Lecture. But
though full and final, this definition is not explicit; and it still
remains to evolve it into a more precise expression.
Now, when we say that Logic is the science of the necessaiy
forms of thought, what does the quality of necessity here imply ?
"In the first place, it is evident that in so far
Form of thought. — „ ,. , , . , • ^
Four conditions of its ^^^ ^o™ ^^ thought IS ncccssary, this form
necessity. must be determined or necessitated by the na-
1. Determined by the . ture of the thinking subject itself; for if it
naureo e in ing -^^re determined by anything external to the
subject it-self. j j is
mind, then would it not be a necessary, but a
merely contingent determination. The first condition, therefore,
3
18 LOGIC. Lect. n.
of the necessity of a form of thought is, that it is subjectively, not
objectively, determined.
"In the second place, if a form of thought be subjectively neces-
sary, it must be original and not acquired. For
2. Original. . . .•" . n , , ,
II It were acquired, there must have been a time
when it did not exist ; but if it did ever actually not exist, we must
be able at least to conceive the possibility of its not existing now.
But if we are so able, then is the form not necessary; for the crite-
rion of a contingent cognition is, that we can represent to ourselves
the possibility of its non-existence. The second condition, there-
fore, of the necessity of a form of thought is, that it is original, and
not acquired.
" In the third place, if a form of thought be necessary and origi-
nal, it must be universal ; that is, it cannot be
3. Universal. ... • t i
that it necessitates on some occasions, and does
not necessitate on others. For if it did not necessitate universally,
then would its necessitation be contingent, and" it would conse-
quently not be an original and necessary principle of mind. The
third condition, therefore, of the necessity of a form of thought is,
that it is universal.
" In the fourth place, if a form of thought be necessary and uni-
versal, it must be a law ; for a law is that which
applies to all cases without exception, and from
which a deviation is ever, and everywhere, impossible, or, at least,
unallowed. The fourth and last condition, therefore, of the neces-
sity of a form of thought is, that it is a law."* This last condition,
likewise, enables us to give the most explicit enunciation of the
object-matter of Logic, in saying that Logic is
The Object-matter ^^xe Science of the Laws of Thought as Thought,
of Logic explicitly , . /» i -n it r. mi i
enounced ®^ ^"^ sciencc oi the t ormal Laws of Thought, or
the science of the Laws of the Form of Thought ;
for all these are merely various expressions of the same thing.
Before proceeding further, it may be proper
General historical ^q ^sikQ a very general retrospect of the views
re rospec <> ^'^^^^ *» ^\^c^^^ have prevailed in regard to the object artd
regard to the object _ r^ ^ ® ** _
and domain of Logic. domain of Logic, from the era when the science
received its first giand and distinctive develop-
ment from the genius of Aristotle to the present time.
I may say, in general, that the view which I
Merit of the Author's j^^^,^ ^^^ presented to you of the object and
view of Logic. ...
domain of Logic, is the one which concentrates,
corrects, and completes the views which have been generally held
1 EsBer, LogUc, i 6, pp. 9, 10, with a few original interpolations. — Ed
Lect. n. LOGIC. 19
by logicians of the peculiar province of their science. It is the one
to which they all gravitate.
It is unfortunate, that by far the greater number of the logical
writings of Aristotle have perished, and that
Aristotle. . i .1 • , , . .
those which reraam to us exhibit only his views
of the science considered in its parts, or in certain special relations.
None of the treatises which are now collected in the Organon^
considers the science from a central point; and we do not even
possess a general definition of Logic by its illustrious founder.' It
<V^ould, therefore, be unjust to the mighty master, if, as has usually
been done, we estimated his conception of the science only by the
partial views contained in the fragmentary or special treatises which
have chanced to float ashore from the genei'al wreck of his logical
writings. These by themselves are certainly enough to place the
Stagirite high above comparison with any subsequent logician ; but
still, if he has done so much in the half-dozen treatises that still
remain, what may we not conceive him to have accomplished in
the forty which are recorded and seem to have been lost ? It is,
therefore, not to be attributed to Aristotle, that subsequent logi-
cians, mistaking his surviving treatises of a logical nature — few in
number, and written, in general, not in exposition of the pure sci-
ence, but only of the science in cer^in modified applications — for
a systematic body of logical doctrine, should have allowed his views
of its partial relations to influence their conceptions of the science
absolutely and as a whole. By this influence of the Aristotelic
treatises, we may explain the singular circumstance, that, while
many, indeed most, of the subsequent logicians speculatively held
the soundest views in regard to the proper object and end of Logic,
few or none of them have attempted by these views to purify the
science of those extraneous doctrines, to which the authority of
Aristotle seemed to have given a right of occupancy within its
domain. I shall not attempt to show you, in
Greek Aristotelians ^ i_ j. • ^ ^i , •
^ ^ ,. „ ^ , extenso, how correct, in general, were the notions
and Latin Schoolmen. \ ' o '
entertained by the Greek Aristotelians, and even
by the Latin schoolmen, for this would require an explanation of
the signification of the terms in which their opinions were embod-
ied, which would lead me into details which the importance of the
matter would hardly warrant. I shall only say, in general, that, in
their multifarious controversies under this head, the diversity of
their opinions on subordinate points is not more remarkable than
their unanimity on principal. Logic they all discriminated as a sci-
1 See below, p. 24. — Ed.
'iQ LOGIC. Lect. it
ence of the form and not of the matter of thought.' Those of ttie
schoolmen who held the object of Logic to be things idn general,
held this, however, under the qualification that things in general
, were not immediately and in themselves considered by the logician,
. but only as they stood under the general forms imposed on them
by the intellect (" quatenus secundis intentionibus substabant "), —
a mode of speaking which is only a periphrasis of our assertion, that
Logic is conversant about the forms of thought." The other scliool-
men, again, who maintained that the object of Logic was thought
in its processes of simple apprehension, judgment, and reasoning
(three, two, or one), carefully explained that these operations were
not in their own nature proposed to the logician, for as such they
belonged to Animastic, as they called it, or Psychology, but only in
so far as they were dirigible or subject to laws, — a statement which
is only a less simple expression of the fact, that Logic is the science
.of the laws of thought.' Finally, those schoolmen who held that
the object-matter of Logic was found in second notions as applied
to first, only meant to say that Logic was conversant Avith concep-
tions, judgments and reasonings, not in themselves, but only as i-eg-
ulators of thought,'* — a statement which merely varies and per-
plexes the expression, that the object of Logic is the formal laws
of thought.
The same views, various in appearance, but, when analyzed, es-
sentially the same, and essenti.illy correct, may
Leibnitio-woifian j^^ ^^.^^^^^ through the Leil)nitio-W<)lfian school
and Kantian Schools. . ^ • i-
into the Kantiaii ; so tliat, while it must be
owned that they were never adequately carried out into priicticnl
application, it cannot be denied that they were theoretically not
unsound.
The conntiy in which, perhaps, the nature of
Bacon, — Locke. ^ . •• i i i a ii
Logic has been most completely and generally
misunderstood, is Great Britain. Bacon wholly misconceived
1 "Logicus solas considerat formas inten- ideo qujedam secundse intentiones invent*
tionum communes." Albertus Magnus, In sunt ad regulandum discursum, de quibus
De Anima, L. I. trac. i. c. 8. For various proprie est Logica " See also Zabarella and
I scholastic theories on the object-matter of Camerarius as above. — Ed.
. Logic, see Scotus, Super Univ. Porphyrii, On. , ,_, . _. nt-r t> • i .
•'■ rrv ,, ,^ ,r r ,-1. • 3 [Camefarius, Bifp. Phil., V. i. qu. 1, p.
111.: Zabarella, X)e Natura iMgicfr, ho. \. cap. „ »., , o. l « r.L-> l- an- n .
,„'.,.' „. .. , ., 3. —Ed.] Schuler, PAi/oioM'OjP- 30(,[L. V ,
19; Smiglecius, Z.ogico, Disp. u. qu. 1 ; Came- , . », . j ,i /■, „•.■ i-co
„. . „f, ,. „ . Z.off(ca, Exer. 1., ed. Hagae Comitis, 1(63 —
ranus, Ditiputattones Phnosophicee, F&n. i. qu. „ , V^, . , . -r, • nn^ . .■ -r .•
■ ' ' ,^ '. . ,„- Ed.1 D'Abra de Raconis, [Tratiatio Totita
Ku. 2, et seq. Compare DucwstoTU, p. 138. „, ., .. „ , .. r t> .» „ i « >to
' ff Philosophiee, Praeludia Logica, Post., c. i. p. 4.8,
4 r/- T -I- J n T,T . A .■ T^ cd. Parisiis, 1640. — Ed.]
8 [G. J. Vossius, De Nat. Artium stve De '
Logica, c. iv] - Compare Alex, de Ales, In < See Zabarella and Camerarius, as above.
Metaph. 1. iv. t. 5. "Dialectica est inventa ad — Ed. [Compare Poncius, Cursus Philosophi-
regulandum discursum intellectus et rationis; ct«, Disp. i. qu. ult., p. 48, 2d ed. Paris, 1649 !
itp^ cl^ai;acter in certain respects;, but his errors are insignificant,
wnen compared with the total misapprehension of its nature by
l,ocke. Tl^e character of these mistakes I shall have occasion to
iliustrate in the sequel; at present I need only say, that, while
those who, till lately, attempted to write on I^iogic in the English
language were otherwise wholly incompetent to the task, they, at
the same time, either shared the misconceptions of its nature with
Xiocke, or only contributed, by their own hapless attempts, to jus-
tify the prejudices prevalent against the science which they professed
to cultivate and improve.
It would be unjust to confound with other attempts of our country-
men in logical science the work of Di\ "V^bately.
whateiy,- general rpj^^ author, if not endowed with any high tal-
cbaracter of his Ele- n ^ ^^ i • i i •
j^gjjjg « ent for philosophical speculation, possesses at
least a sound and vigorous understanding. He
unfortunately, however, wrote his Elements of Logic in singular
unacquaintance with all that had been written on the science in
a,ncient and in modern times, with the exception, apparently, of two
works of two Oxford logicians, — the Institutio of Wallis, and the
Compendium of Aldrich, — both written above
Aid '^h ^ century ago, neither of them rising above a
humble mediocrity, even at the date'of its com-
position ; and Aldrich, whom Whateiy unfortunately regards as a
safe and learned guide, had himself written his book in ignorance
of Aristotle and of all the principal authors on the science, — an
ignorance manifested by the grossest errors in the most elementary
parts of the science. It is not, therefore, to be wondered at, that
the Elements of Whateiy, though the production of an able man,
are^so far behind the advancement of the science of which they
treat ; that they are deformed with numerous and serious errors ;
and that the only recommendation they possess, is that of being the
best book on the subject in a language which has absolutely no
other deserving of notice I*
i have now, therefore, to call your attention lo Dr. Whately's
account of t^ie object-matter and domain of
Whateiy '8 view of Logic. "The treatise of Dr. Whateiy," says his
e o jec ma er an Vice-Princi,pal and epitomator Dr. Hinds,^ " dis-
ci omam of Logic stat- ' **. . -r € '
e4 and criticized. P^ys^ and i^ is ^he .o^ly oue that has clearly
done so, the true nature and use of Logic ; so
that it may be approached no longer as a dark, curious, and merely
I See Dhextssions, p. ^, second edition, 2 Introduction to Logic, Preface, p. vilL Qjc-
22 LOGIC. Lect. IL
speculative study, such as one is apt in fancy to class with astrology,
and alchemy."
Let us try whether this eulogy be as merited as it is unmeasured.
Now, Dr. Whately cannot truly be said clearly to display the na-
ture of Logic, because in different passages he
Whately proposes to proposes to it different and contradictory ob-
Losic different and ., ji . ■, •j^j-i ^x. ^
^ _,. ^. ^ lects ; and he cannot be said to display the true
contradictory object- «* ' ^ r .^ ^
matter. nature of Logic, for of these different objects
there is not one which is the true.
In several passages,^ he says that " the process or operation of
reasoning is alone the appropriate province of Logic." Now, this
statement is incorrect in two respects. In the first place, it is in-
correct, inasmuch as it limits the object-matter of Logic to that
part of the Discursive Faculty which is especially denominated
Reasoning. In this view Logic is made convertible with Syllogis-
tic. This is an old error, which has been fi-equently refuted, and
into which Whately seems to have been led by his guide Dr. Wallia.
In the second place, this statement is incorrect, inasmuch as it
makes the process, or, as he also calls it, the op-
The operation of Kea- eration, of reasoning the object-matter of Logic.
Boningno e o jec - jj^qw a definition which merely afiirms that
matter ot Logic, as ' _ _ •'
Whately affirms. Logic is the scieucc which has the process of
reasoning for its object, is not a definition of
this science at all; it does not contain the differential quality by
which Logic is discriminated from other sciences ; and it does not
prevent the most erroneous opinions (it even suggests them) from
being taken up in regard to its nature. Other sciences, as Psychol-
ogy and Metaphysic, propose for their object (among the other fac-
ulties) the operation of reasoning, but this considered in its veal
nature : Logic, on the contrary, has the same for its object, but only
in its formal capacity; in fact, it has in propriety of speech nothing
to do with the process or operation, but is conversant only with its
laws. Dr. Whately's definition is therefore not only incompetent,
but delusive ; it would confound Logic and Psychology and Meta-
physic, and tend to perpetuate the misconceptions in regard to the
nature of Logic which have been so long prevalent in this country.
_ . But Dr. Whately is not only wrong as meas-
Whately erroneous- •' -■ , •
ly and contradictorily "'6^ by a foreign Standard, he is wrong as meaa-
makes Language the ured by his own ; he is himself contradictory,
adequate object-mat- You have just secn that, in some places, he
^' ■ makes the operation of reasoning not only the
principal but the adequate object of Logic. Well, in others he
1 See pp. 1, 18, 140, third edition.
Lect. n. LOGIC. 2o
makes this total or adequate object to be language. But as there
cannot be two adequate objects, and as language and the opera-
tion of reasoning are not the same, there is, therefore, a contradic-
tion. "In introducing," he says, "the mention of language previ-
ously to the definition of logic, I have departed from established
practice, in order that it may be clearly understood that logic is
entirely conversant about language ; a truth which most writers on
the subject, if indeed they were fully aware of it themselves, have
certainly not taken due care to impress on their readers."^ And
again : " Logic is wholly concerned in the use of language." ^
In our last Lecture, I called your attention to the ambiguity of
the term Xoyos, in Greek, meaning ambiguously either thought or its
expression; and this ambiguity favored the rise of two counter-
opinions in regard to the object of logic ; for while it was generally
and correctly held to be immediately conversant about the internal
Xoyos, thought^ some, however, on the contrary, maintained that it
was immediately conversant about the external Xoyo9, language.
Now, by some unaccountable illusion. Dr. Whately, in different
places, adopts these opposite opinions, and enunciates them without
a word of explanation, or without even a suspicion that they are
contradictory of each other.*
From what I have now said, you may, in some degree, be able to
judge how far credit is to be accorded to the
The true nature of assertion, that Dr. Whately is the only logician
Logic more correctly ^j^^, ^^.^^ clearly displayed the true nature and
understood by the /. t • t ^ ^ i? • .1 •
scholastic logicians '^se of Logic. In fact, SO far is this assertion
than by Whately. from the truth, that the object-matter and scope
of Logic was far more correctly understood
even by the scholastic logicians than by Dr. Whately ; and I may
caution you, by the way, that what you may find stated in the Ele-
ments of the views of the schoolmen touching the nature and end
of Logic, is in general wrong; in particular, I may notice one
most erroneous allegation, that the schoolmen " attempted to employ
logic for the purpose of physical discovery."
But if, compared only with the older logicians, the assertion of
Dr. Hinds is found untenable, what will it be found, if we compare
Whately with the logicians of the Kantian and Leibnitian schools,
of whose writings neither the Archbishop nor his abbreviator seems
ever to have heard ? And here I may observe, that Great Britain is,
I believe, the only country of Europe in which books are written
by respectable authors upon sciences, of the progress of which, for
1 Page 56. 2 Page 74. 3 Besides most vague. —Jotting.
24 LOGIC. Lect. IL
above a century, they have never taken the trouble to inform
themselves.
The second question, to which in the Introduction to Logic an
answer is required, is, — What is the Value or
Loo-ic ^ ^ ^ y ° Utility of this science ? Before proceeding to
a special consideration of this question, it may
be proper to observe, in general, that the real utility of Logic has
been obscured and disparaged by the false utilities which have too
fi-equently been aiTogated to it ; for when logic was found unable
to accomplish what its unwise encomiasts had promised, the recoil
was natural, and as it failed in performing everything, it was lightly
infen-ed that it coidd perfonn nothing. Both of these extremes are
equally erroneous. There is that which Logic can, and there is that
which Logic cannot, perform ; and, therefore, before attempting to
show what it is that we ought to expect from the study of this
science, it will be proper to show what it is that we ought not. I
shall therefore, in the first place, consider its false utilities, and, in
the second, its true.
The attribution of every false utility to Lo^c has arisen from er-
roneous opinions held in regard to the object of
utilities falsely at- ,, . c^ i •. t i .
tributedtoLo ic science. ho long as it was supposed that
logic took any cognizance of the matter of
thought, — so long as it was not distinctly understood that the form
of thought was the exclusive object of this science, and so long as
it was not disencumbered of its extraneous lumber, — so long must
erroneous opinions have been prevalent as to the nature and oomi-
prehension of its end.
It was accordingly, in the fi^rst place, frequently supposed that
Logic was, in a certain sort, an instrument of
As an instrument of . ,.^ ,. rrii .-.i /» >-■>
. ... ,. scientmc discovery. Ihe title oi Orqanoix, —
scientific discovery. •' if ~i
instrument^ — bestowed on the collectioh we
possess of the logical treatises of Aristotle, contributed to this ei^
ror. These treatises, as I observed, are but a few of the many writ-
ings of the Stagirite on Logic, and to him we owe neither the order
in which they stand arranged, nor the general name under whicli
they are now comprehended.* In later times, these treatises were
supposed to contain a complete system of Logic, and Logic was
viewed as- the organ not only of Pliilosophy, but of the sciences in
general. Thus it was that Logic obtained not only the name of in-
strument^ or instrumental philosophy^ but many other high-sound-
1 See Brandis AristoteUs, seine akac/emis:hfn 140. Trendelenburg, EletTunta Log. AmtoC,
Zeitgenossen und n'dchsten Nachfalgery P. i. p. p. 38.— Ed.
liECT. n. LOGIC. 25
ing titles. It was long generally styled the Art of arts and Sci-
ettce of sciences. " Logica," says Scotus, " est ars artiuiu et scien-
tia scientiarum, qua aperta, omnes aliae aperiuntur; et qua clausa,
omnes aliae clauduntur ; cum qua quaelibet, sine qua nulla." ^ In
modern times, we have systems of this science under the titles of
Via adVeritatem^ — Gynosura Veritatis^ — Caput et Apex Philos-
ophim^ — Heuristica, sive Introductio ad Artem Inveniendi^ etc.
But it was not only viewed as an instrument of discovery, it was
likewise held to be the infallible corrector of our
As the corrector of • j. n ^ i • ^i, • • a. c ' a. ^
. „ , . intellectual vices, the invisforator of our intel-
intellectual vices. ...
lectual imbecility. Hence some entitled their
Logics, The Medicine of the Mind^ The Art of Thinking^ The
Lighthouse of the Intellect^ The Science teaching the Right Use
• of Measo7i^ etc., etc. Now, in all this there is a mixture of truth
and error. To a certain extent, and in certain points of view. Logic
is the organ of philosophy, the criterion of truth, and the corrector
of error, and in others it is not.
In reference to the dispute, whether logic may with propriety be
called the instrument^ the organon of the other
In what respect Logic scicHces, the question may be at once solved by
is an instrument of the t.>.. • r\ • i i t i
„„.„„„„ a distinction. One science may be stvled the
instrument of another, either in a material or in
a formal point of view. In the former point of view, one science is
the organ of another when one science determines for another its
contents or objects. Thus Mathematics may be called the material
instrument of the various branches of physical science ; Philology —
or study of the languages, Latin, Greek, Hebrew, Chaldee, etc.,
with a knowledge of their relative history — constitutes a material
instrument to Christian Theology; and the jurist, in like manner,
finds a material instrument in a knowledge of the history of the
country whose laws he expounds.^" Thus, also. Physiology, in a
\ MnMritii JBxpositio QueBstionum Doctoris 5 Gunner, Ars Heuristica Intelleclvalis, Lip-
Subtilis in quinque Universalia Porphyrii, Quaest. sise, 1756. Traltato di Messer Sebasliano Erizzo,
i. {Scoti Opera, Lugd. 1639, torn. i. p. 434.) deW Instrumento et Via Inventrice de gli antichi
Mauritius refers to St. Augustin as his author- nelle scientie, Venice, 1554. — Ed.
ity for the above quotation. It slightly re- 6 Tschirnhausen, Medicina Mentis, sive Arlis
sembles a passage in the De Ordine, 1. ii. c. 13. Inveniendi Prcecepta Generalia, Amst. 1687. y
— Ed. Lange, Medicina Mentis, Hal%, 1703. — Ed.
2 Gundliug, Via ail Veritatem Moralem, Ha- 7 L'Art de Penser, commonly known as the /
Jje, 1713. Daries, Via ad Veritatem, Jenae, Port Royal Logic. Several other works have
1764 (2d edit). —Ed. appeared under the same title. — Ed.
3 P, Laurembergiug, Cynosura Bona Mentis , 8 Grosserus, P/tarus intellecttts, sive Logica
». Logica Rostoch, 1633. R. Loenus, Cynosura Electiva, Lips., 1697. —Ed.
Rationis, Arnhem, 1667. — Ed. ^ 9 Watts, Logic, or the Right Use oj Reason. -~^
4 See Krujr, Logik,.^ 9, p. 23, from whom Ed.
several of the above definitions were probably 10 See Genovesl, p. 41, [Elementorum Artis
taken. — Ed. Logica ■ Oitica Libri T. , 1 . i. C. iii. — Ed.]
4
26 LOGIC. Lect. li.
material point of view, is the organon of medicine ; Aristotle has
indeed well said, that medicine begins where the philosophy of
nature leaves oiF.^ In the latter point of view, one science is the
organon of another, when one science determines the 'scientific
form of another. Now, as it is generally admitted that Logic
stands in this relation to the other sciences, as it appertains to
Logic to consider the general doctrine of Method and of sys-
tematic construction, in this respect Logic may be properly
allowed to be to the sciences aii instrument, but only a formnl
instrument.^
In regard to the other titles of honor. Logic cannot with pro-
priety be denominated a [Heuretic or] Art
ogic not proper y ^^ Discoverv. " For discoverv or invention is
an art of discovery. •' •'
not to be taught by rules, but is either the
free act of an original genius, or the consequence of a lucky acci-
dent, which either conducts the finder to something unknown, or
gives him the impulse to seek it out. Logic can at best only analyt-
ically teach how to discover, that is, by the development and dis-
memberment of what is already discovered. By this process there
is nothing new evolved, and our knowledge is not amplified ; all
that is accomplished is a cleai-er and disrtncter comprehension of
the old ; our knowledge is purified and systematized." ^ It is
well observed by Antonius, in Cicero : " Nullum est praeceptum
in hac arte quomodo verum inveniatur, sed tantum est, quomodo
judicetur."^ Logic is thus not creative; it is only plastic, only
formative, in relation to our knowledge.
Again: "Logic cannot with propriety be styled the medicine of
the mind, at least without some qualifying ad-
in what sense Logic jectivc, to sliow that the Only remedy it can
can be styled the med- , . c ^ i -i • i
icine of the mind. ^PPv ^^ *o our lormai errors, while our matenal
errors lie beyond its reach. This is evident.
Logic is the science of the formal laws of thought. But we cannot,
in limiting our consideration to the laws of formal thinking, investi-
gate the contents, — the matter of our thought. Logic can, there-
fore, only propose to purge the understanding of those errors which
lie in the confusion and perplexities of an inconsequent thinking.
This, however, it must be confessed, is no radical cure, but merely a
purification of the understanding. In this respect, however, and to
this extent. Logic may justly pretend to be the medicine of the
1 De Sensn et Sensili, c. i. 3 Krug, Logik, J 9, p. 24. — Ed. Cf. [Rich*
2 Krug, Logik, § 9, p. 23: Cf. Platner, Philo- ter, Logik, p. 83 et seq.]
iophische Aphorismen, I't. i, p. 23, ed. 1793.— Ed. < De Oratore, ii. 38. — Ed.
Lect. n. LOGIC. 27
mind, and may therefore, in a formal relation, be styled, as by some
logicians it has in fact been, Catharticon intellectus.
" By these observations the value of Logic is not depreciated ;
they only prepare us to form an estimate of its real amount. Pre-
cisely, in fact, as too much was promised and expected from thi*
study, did it lose in credit and esteem." ^
1 Krug, Logik, s 9, pp. 24-6. — Ed. Cf. tBichter, Logik, p. 86.]
LEGTUBE III.
INTRODUCTION.
LOGIC — n. ITS UTILITY — III. ITS DIVISIONS — SUBJECTIVE
AND OBJECTIVE — GENEKAL AND SPECIAL.
The last Lecture was occupied with the consideration of the
latter part of the introductory question, — What
BecapitulatioD. -x-r. iii /.i\. n.
IS Logic r and with that of the nrst part oi the
second, — What is its Utility ? In the Lecture preceding the last,
I had given the definition of Logic, as the science of the laws of
thought as thought, and, taking the several parts of this definition,
had articulately explained, 1°, What was the meaning and history
of the word Logic ; 2°, What Avas the import of the term science^
the genus of Logic ; and, 3°, What was signified by laws of thought
as thought, the object-matter of Logic, This last I had considered
under three heads, explaining, 1°, What is meant by thought ; 2°,
What is meant by thought as thought ; and, 3°, What is meant by
laws of thought as thought. It was under the last of these heads
that the last Lecture commenced. I had, in the preceding, shown
that the form of thought comprises two kinds of phenomena, given
always in conjunction, but that we are able by abstraction and
analysis to discriminate them from each other. The one of these
classes comprehends what is contingent, the other what is necessary,
in the manifestations of thought. The necessary element is the
peculiar and exclusive object of Logic; whereas the phaenomena of
thought and of mind in general are indiscriminately proposed to
Psychology. Logic, therefore, I said, is distinguished from the
other philosophical sciences by its definition, as the science of the
necessary form of thought. This, however, though a full and final
definition, is capable of a still more explicit enunciation; and I
showed how we are entitled to convert the term necessary into the
term laws; and, in doing so, I took the opportunity of explaining
how, the necessity of a mental element being given, there is also
implicitly given the four conditions, 1°, That it is subjective; 2°,
That it is original ; 3°, That it is universal ; and, 4°, That it is a
law. The full and explicit definition of Logic, therefore, is, — the
Lkct. III. ■ LOGIC. 29
science of the Laws of Thought as Thought; or, the science of the
Laws of the Foi-m of Thought ; or, the science of the Formal Laws
of Thought; — these being only three various expressions of what
is really the same.
Logic being thus defined, I gave a brief and general retrospect
of the history of opinion in regard to the proper object and domain
of Logic, and showed how, though most logicians had taken, specu-
latively and in general, a very correct view^ of the nature of their
science, they had not c'arried this view out into application, by
excluding from the sphere of Pure and Abstract Logic all not
strictly relative to the form of thought, but had allowed many
doctrines relative merely to the matter of thought to complicate
'arid to deform the Science.
I then called attention to the opinions of the author whom I
recommend' to your attention, and showed that Dr. Whately, in his
statements relative to the object-matter of Logic, is ' vague sin d
obscure, erroneous and self-contradictory; and that so far from
being entitled to the praise of having been the only logician who
has clearly displayed the true nature of the science, on the contrary,
in the exposition of this nature, he is far inferior, not only in per-
spicuity and precision, but in truth, to the logicians of almost every
age and country" except our own.
And here, taking a view of what we have already established,
I would interpolate some observations which I
Observations inter- ought in my last Lecture to have made, before
posed relative to the < , . . i_ • i ^. /. .i j? ^ x-
„,. . . leavmg the consideration oi the nrst question,
question, — n hat is ^ ° _ ^
Logic? — viz., What is Logic ? Logic, we have seen, is
exclusively conversant about thought, — about
thought considered strictly as the operation of Comparison, or the
faculty of Relations ; and thought, in this restricted signification, is
the cognition of any mental object by another in which it is consid-
ered as included ;^ in other words, thought is the knowledge of
.-, things under conceptions. By the way, I would
The terms Conception t x i i a* xi
_, „ here pause to make an observation upon the
and Concept. ^ ^
word cofiception, and to prepare you for the em-
ployriient of a term which I mean hereafter to adopt. You are
aware, from what I have already said, that I do not use conception
in the signification in which it is applied by Mr. Stewart. He
usurps it in a very limited meaning, in a meaning which is peculiar
to himself, — viz., for the simple and unmodified representation of
an object presented in Perception.' Reid, again, vacillates in the
signification he attaches to this term, — using it sometimes as a
1 See Lectures on Metaphysics, lect. xxxiii. p. 452. — Ed.
so LOGIC. Lect. m.
synonym for Imagination, sometimes as comprehencling not only
Imagination, but Undei-standing and the object of Understanding.^
It is in the latter relation alone that I ever em-
Author-s employment . • ^^^ ^j^j^ -^ -^^ correct and genuine signi-
of these terms. i
fication, whether we regard the derivation of
the word, or its general use by philosophers. Conception, in English,
is equivalent to conceptio and concepUis in Latin ; and these terms,
by the best philosophei-s, and the most extensive schools, have been
employed as synonymous for notion (notio), the act or object of the
Understanding Propei*, or Faculty of Relations. So far, therefore,
you are sufficiently prepared not to attribute to the word conception,
when you hear it from me, the meaning which it bears in the philo-
sophical writings with which you are most likely to be familiar.
What is the precise meaning of the term will be soon fully ex-
plained in its proper place, wben we commence the treatment of
Logic itself. But what I principally pause at present to say is —
that, for the sake of perspicuity, I think it necessary, in reference to
this word, to make the following distinction. The term conception,
like perception, imagination, etc., means two things, or rather the
same thing in two different relations, — relations, however, which it
is of great importance to distinguish, and to mark the distinction
by the employment of distinct words. Conception means both the
act of conceiving, and the object conceived; a?, perception, both the
act of perceiving, and the thing perceived; imagination, both the
act of imagining, and what is imagined. Now, this is a source of
great vagueness in our philosophical discussions : have we no means
of avoiding this inconvenience? I think we have; and that, too,
without committing any violence upon language. I would propose
the following distinction : For the act of conceiving, the tenn con-
ception should be employed, and that exclusively ; while for the
object of conception, or that which is conceived, the term concept
should be uscd.^ Concept is the English of the Latin conceptum, —
id quod conceptum est, — and had it no vested right as an actual
denizen of the language, it has good warrant for its naturalization.
There are a thousand words in English formed on precisely the
same analogy, as precept, digest, etc., etc. But we have no occasion
to appeal to analogy. The term concept was in common use among
the older philosophical writers in English,^ though, like many other
valuable expressions of these authors, it has been overlooked by our
1 See Leetttres on Metaphysics, lect. xxxiii. p. intellijjendi." See Occam, In Sent., 1. 1. d. 2,
452. — Ed. qu. 8; and Biel, 1. i. d. 3, q. 5]
2 See Biel, [ la Sent., 1. i. dist. 2, qu. 8; 1. ii. 3 See Zacliary Coke, Art of Logiek. London
Uist. 2, qu. 2 By Occam and most others, 1654, pp. 11, 101, et alibi; Gideon Harvey,
eonceptus is used as " id quod terminat actum Archelogia Phiiosophica Nova, or New PrincipUi
LecT. in. LOGIC. 31
English lexicographers. I may add, that nearly the same fortune
has befallen the tei-m in French. Concept was in ordinary use by
the old French philosophers, but had latterly waxed obsolete. It
has, however, I see, been reinstated in its rights since the reawaken-
ing of philosophy in France ; and, in particular, it is now employed
in that language in translating from the German the term Begriff.
I shall, therefore, make no scruple in using the expression concept
for the object of conception, and conception I shall exclusively em-
ploy to designate the act of conceiving. Whether it might not, in
like manner, be proper to introduce the term percept for the object
of perception, I shall not at present inquire.
But to return from this digression. Logic, we have seen, is ex-
clusively conversant about thought strictly so
Analogy between denominated, and thought proper, we have seen,
Logic and Mathemat- jg ^hg cognition of One objcct of thought by an-
other, in or -under which it is mentally included ;
— in other words, thought is the knowledge of a thing through a
concept or general notion, or of one notion through another. In
thought, all that we think about is considered either as something
containing, or as something contained; — in other words, every pro-
cess of thought is only a cognition of the necessary relations of our
concepts. This being the case, it need not move our wonder that
Logic, within its proper sphere, is of such irrefragable certainty,
that, in the midst of all the revolutions of philosophical doctrines,
it has stood not only unshattered but unshaken. In this respect.
Logic and Mathematics stand alone among the sciences, and their
peculiar certainty flows from the same source. Both are conversant
about the relations of certain a priori forms of intelligence: —
Mathematics about the necessary forms of Imagination; Logic about
the necessary forms of Understanding ; Mathematics about the re-
lations of our representations of objects, as out of each other in
space and time ; Logic about the relations of our concepts of ob-
jects, as in or under each other, that is, as, in different relations,
respectively containing and contained. Both are thus demonstra-
tive or absolutely certain sciences only as each develops what is
given — what is given as necessary, in the mind itself. The laws
of Logic are grounded on the mere possibility of a knowledge
through the concepts of the Understanding, and through these we
know only by comprehending the many under the one. Concern-
ing the nature of the objects delivered by the Subsidiary Faculties
of Philosophy. Lend. 1663, P. i., b. ii., c. 4, p. Baynes, New Analytic of Logical Forms, pp. 5
22. For several authorities for the use of this 6, note. — Ed.
term among the older English logicians, see
82 LOGIC. Lect. Ill
to the Elaborative, Logic pronounces nothing, but restricts its con-
sideration to the laws according to which tlieir agreement or disa-
greement is affirmed.*
It is of itself manifest that every science must obey the laws of
Logic. If it does not, such pretended science
Logic is the negative j^ ^^^ founded ou reflection, and is only an irra-
condition of tratn. . ah-/.
tional absurdity. All inference, evolution, con-
catenation, is conducted on logical principles — principles which
are ever valid, ever imperative, ever the same. But an extension
of any science through Logic is absolutely impobsible ; for by con-
forming to logical canons we acquire no knowledge — receive noth-
ing new, but are only enabled to render what is already obtained
more intelligible, by analysis and arrangement. Logic is only the
negative condition of truth.^ To attempt by a mere logical knowl-
edge to amplify a science, is an absurdity as great as if we should
attempt by a knowledge of the grammatical laws of a language to
discover what was written in this language, without a perusal of the
several writings themselves. But though Logic cannot extend,
cannot amplify a science by the discovery of new facts, it is not to
be supposed that it does not contribute to the progress of science.
The ])rogress of the sciences consists not merely in the accumulation
of new matter, but likewise in the detection of the relations subsist-
ing among the materials accumulated ; and the reflective abstraction
by which this is eflfected, must not only follow the laws of Logic,
but is most powerfully cultivated by the habits of logical study.
In these intercalary observations I have, however, insensibly en-
croached upon the second question, — What is the Utility of Logic?
On this question I now dictate the following paragraph :
% IV. As the rules of Logic do not regard the matter bat*
only the form of thought, the Utility of
Pap. IV. utuity of Logic must, in like manner, be viewed as
Logic. ,. ® , . . ^
limited to Its influence on our mnnror of
thinking, and not sought for in any effect it can exert upon
what M'e think about. It is, therefore, in the first place, not to
be considered useful as a Material Instrument, that is, as a mean
of extending our knowledge by the discovery of new truths ;
but merely as a Formal Instrument, that is. as a mean by which
knowledge, already acquired, may be methodized into the form
accommodated to the conditions of our understanding. In the
.•■econd place, it is not to be regarded as a JMedicino of the minfl
1 Cf. Bachmann, LoyiJc, Einlcitung, § 20. 2 [AnoilloD, Esitais Philosnp/uques, t. iL p
Edit. 1828. —Ed. 291.]
lect. m.
L 0 r. I c . 33
to the extent of reniedyino: the vnrious errors which originate
in the nature of the objects of our knowledge, but merely to
the extent of purging the mind of those errors which arbe
from inconsequence and confusion in thinking.*
Logic, however, is still of eminent utility, not only as presenting
to us the most interesting object of contemplation in the mechanism
of human thought, but as teaching how, in many relations, to dis-
criminate truth from error, and how to methodize our knowledge
into system ; while, at the same time, in turning the mind upon
itself, it affords to our higher faculties one of their most invigorating
exercises. Another utility is, that Logic alone affords us the means
requisite to accomplish a rational criticism, and to communicate its
results.
What is now summarily stated in the preceding paragraph, I
illustrated, in my last Lecture, in detail, — in so far as it was requis-
ite to disencumber the real value of our science from those false
utilities which, in place of enhancing its worth in the opinion of
the world, have, in fact, mainly contributed to reduce the common
estimate of its importance far beneath the truth. I now proceed
to terminate what I have to say under this head by a few words, in
exposition of what renders the cultivation of Logic — of genuine
logic — one of the most important and profitable of our studies.
" Admitting, therefore, that this science teaches nothing new, —
that it neither extends the boundaries of knowl-
Logic gives us, to a ^^ j^^^ unfolds the mysterics which lie beyond
certain extent, domin- n i n • r i^
ion over our thoughts. ^^^ compass of the reflective intellect, — and
that it only investigates the immutable laws to^
which the mind in thinking is subjected, still, inasmuch as it devel-
ops the application of these laws, it bestows on us, to a certain ex-
tent, a dominion over our thoughts themselves. And is it nothing
to watch the secret workshop in which nature fabricates cognitions
and thoughts, and to penetrate into the sanctuary of self-conscious-
ness, to the end that, having learnt to know ourselves, we may be
qualified rightly to understand all else? Is it nothing to seize the
helm of thought, and to be able to turn it at our will ? For, through
a research into the laws of thinking, Logic gives us, in a certain:
sort, a possession of the thoughts themselves. . It is true, indeed,,
that the mind of man is, like the universe of matter, governed by
eternal laws, and follows, even without consciousness, the invari-
able canons of its nature. But to know and understand itself and
1 Cf. Krug, Logik, i 9. — Ed.
5
34 LOGIC. lect. in.
out of the boundless chaos of phaenomena presented to the senses
to form concepts, through concepts to reduce that chaos to harmony
and arrangement, and thus to establish the dominion of intelligence
over the universe of existence, — it is this alone which constitutes
man's grand and distinctive preeminence."^ "Man," says the great
Pascal, "is but a reed, — the very frailest in nature ; but he is a reed
that thinks. It needs not that the whole universe should arm to
crush him. He dies from an exhalation, from a drop of water. But
should the universe conspire to crush him, man would still be nobler
than that by which he falls ; for he knows that he dies; and of the
victory which the universe has over him, the universe knows noth-
ing. Thus our whole dignity consists in thought Let
us labor, then, to think aright; this is the foundation of morality." ■^
In the world of sense, illusive appearances hover around us like
evil spirits ; unreal dreams mingle themselves
Supplies in part the ^-^.j^ ^^^^ knowledge; the accustomed assumes
criterion of truth from /, . ., , . .
^^j.^j. the character oi certainty ; and the associations
of thought are mistaken for the connections of
existence. We thus require a criterion to discriminate truth from
error ; and this criterion is, in part at least, supplied to us by Logic.
Logic teaches us to analyze the concrete masses of our knowledge
into its elements, and thus gives us a clear and distinct apprehension
of its parts, it teaches us to think consistently and with method, and
it teaches us how to build up our accumulated knowledge into a firm
and harmonious edifice.^ " The study of logic' is as necessary for
correct thinking, as the study of grammar is for correct speaking ;
were it not otherwise and in itself an interesting study to inves-
tigate the mechanism of the human intellect in the marvellous
processes of thought. They, at least, who are familiar with this
mechanism, are less exposed to the covert fallacies which so easily
delude those unaccustomed to an analysis of these processes."*
But it is not only by aflfording knowledge and skill that Logic is
thus useful ; it is perhaps equally conducive to
nv gora es e n- ^j^^ same end by bestowing power. The retor-
derstanding. _ •' or
sion of thought upon itself — the thinking of
thought — is a vigorous effort, and, consequently, an invigorating
exercise of the Undei*standing ; and as the understanding is the in-
strument of all scientific, of all philosophical, speculation. Logic, by
preeminently cultivating the understanding, in this respect likewise
1 [Heinrich Richter], [ W?r den Gegenstand FaugAre.) Compare Discusfiom, p. 811.—
und den Vmfang der Logik, pp. 3, 4, Leipsio, Ed.
1825. — Ed. ] 3 Cf. Richter, Logik, pp. 6, 6, 12. — El>
V Pensies, P. 1. art. iv. } 6, (vol. ii. p. 84. ed. 4 Krug, Logik, ( 9, p. 26. — £d.
LrcT. m. LOGIC. 35
vindicates its ancient title to be viewed as the best preparatory dis-
cipline for Philosophy and the sciences at large.
There is, however, one utility which, though of a subordinate
kind, I must not omit, though I do not remember to have seen it in-
sisted on by any logical writer. In reference to this, I give you the
following paragraph :
f V. But Logic is further useful as affording a Nomenclature
of the laws by which legitimate thinking
Par. V. Utility of .
Logic, -as affording is govemcd, and of the violation of these
a Bcientiflc nomenoia- \siws, throug^h which thought bccomes vicious
ture. -
or null.
Illustration. It is Said, in Hudibras,* —
" That all a Rhetorician's rules
Serve only bat to name his tools ; "
and it may be safely confessed that this is one of the principal utili-
ties of Rhetoric. A mere knowledge of the rules of Rhetoric can
no more enable us t^o compose well, than a mere knowledge of the
rules of Logic can enable us to think well. There is required from
nature, in both, the faculty ; but this faculty must, in both depart-
ments, be cultivated by an assiduous and also a well-directed exer-
cise; that is, in the one, the powers of Comparison must be ex-
ercised according to the rules of a sound Rhetoric, in the other,
according to the rules of a sound Logic. ' In so far, therefore, the
utility of either science is something more than a mere naming of
their tools. But the naming of their tools,
mportance o a sci- though in itself of little valuc, is valuable as the
enfinc nomenclature. ° ^ ' _
condition of an important function, which, with-
out this, could not be performed. Words do not give thoughts; but
without words, thoughts could not be fixed, limited, and expressed.
They are, therefore, in general, the essential condition of all think-
ing, worthy of the name. Now, what is true of human thought in
general, is true of Logic and Rhetoric in particular. The nomencla-
ture in these sciences is the nomenclature of certain general analy-
ses and distinctions, which express to the initiated, in a single word,
what the uninitiated could (supposing — what is not probable —
that he could perform the relative processes) neither understand nor
express without a tedious and vague periphrasis ; while, in his hands,
it would assume only the appearance of a particular observation, in-
stead of a particular instance of a general and acknowledged rule.
To take a very simple example : there is in Logic a certain sophism,
IP. Cant i. 89 — Ed
S6 LOGIC. Lect. nii
or act of illegal interference, by which two things are, perhaps in a
very concealed and circuitous manner, made to
Example. i i -».t i - •,
prove each other. rJow, the man unacquainted
with Logic may perhaps detect and be convinced of the fallacy ;
but how will he expose it ? He must enter upon a long state-
ment and explanation, and after much labor to himself and others,
he probably does not make his objection clear and demonstrative
after all. But between those acquainted with Logic, the whole
matter would be settled in two words. It would be enough to say
and show that the inference in question involved a drculus in con-
eludendo, and the refutation is at once understood and admitted. It
is in like manner that one lawyer will express to another the ratio
decidendi of a case in a single technical expression ; while their
clients will only perplex themselves and others in their attempts to
set forth the merits of their cause. Now, if Logic did nothing more
than establish a certain number of decided and decisive rules in
reasoning, and afford us brief and precise expressions by which
to bring particular cases under these general rules, it would confer
on all who in any way employ their intellect — that is, on the culti-
vators of every human science — the most important obligation.
For it is only in the possession of such established rules, and of such
a technical nomenclature, that we can accomplish, with facility, and
to an adequate extent, a criticism of any work of reasoning. Logi-
cal language is thus, to the general reasoner, what the notation of
Arithmetic, and still more of Algebra, is to the mathematician.
Both enable us to comprehend and express, in a few significant sym-
bolsj what would otherwise overpower us by their complexity ; and
tfcus it is that nothing would contribute moi^e to facilitate and ex-
tend the faculty of reasoning, than a general acquaintance with the
rules and language of Logic, — an advantage extending indeed to
every department of knowledge, but more especially of importance
to those professions which are occupied in inference, and conversant
with abstract matter, such as Theology and Law.
I now proceed to the third of the preliminary questions — viz.,
How is Logic divided ? Now, it is manifest that
. V M o ^^.^ question may be viewed in two relations ;
for, in asking how is Logic divided, we eitlier
mean how many kinds are there of Logic, or into how many con-
stituent parts is it distributed ?^ We may consider Logic either aa
a universal, or as an integi-ate, whole.
1 Division of Logic into Natural and Artificial, inept.
" He hit! each point -with native force of mind.
Whilst puzzled T>ogic struggles tar behind."
Cf. Krug, LogH, p. 29. Troxler Tagik, i. 48.
Lect. Ill LOGIC. S>T
It is necessary to consider the former question first ; for, before
proceeding to show what are the parts of which
e pecies o ^ logic is made up, it is i-equisite previously to
detennine what the logic is of which these parts
are the components. Under the former head, I therefore give you
the following :
1 VI. Logic,' considered as a Genus or Class, may, in differ-
ent relations, be divided into different Spe-
pe!atioI^to the m Ji ^1^8. And, in the first place, considered by
is.objeotiveand Sub. relation to the mind or thinking subject,
jeouve. Logic is divided into Objective and Subjec-
tive, or, in the language of some older authors, into Logica
systematica and Logica habituaZis}
By Objective or Systematic Logic is meant that complement of
doctrines of which the science of Logic is made
. Explication. c, , . . tt i • it • •
up; by Subjective or Habitual Logic is meant
the speculative knowledge of these doctrines which any individual,
(as Socrates, Plato, Aristotle) may possess, and the practical dex
terity with which he is able to apply them.
Now, it is evident that both these Logics, or, rather. Logic con-
sidered in this twofold relation, ought to be pro
Both these Logics posed to himself by an academical instructor.
ought to be proposed -^^ ... ^ i i. vi T •
„ ,. ^ , , ■ , We must, theretore, neglect neither. Logic con-
as the end of logical ' ' » a
instruction. sidcred as a system of rules, is only valuable as
a mean towards logic considered as a habit of
the mind ; and, therefore, a logical instructor ought not to think
that he fulfils his duty — that he accomplishes all that he is called
on to perform — if he limit himself to the mere enouncement of a
code of doctrine, leaving his pupils to turn his instructions to their
own account as best they may. On the contrary, he is bound to rec-
ollect that he should be something more than a book; that he ought
not only hitnself to deliver the one Logic, but to take care that his
pupils acquire the other. The former, indeed, he must do as a con-
dition of the latter ; but if he considers the systematic logic which
he pronounces, as of any value, except in so far as his pupils convert
it into an habitual logic, he understands nothing of the character of
the function which he attempts to perform. It is, therefore, incuni-
,1 Sec Tirapler, p. 877,- Vossius, p. 217; Pa- various divisions of Logic, seeTimpler, Ln^i-
<;.:;f. ILngicep. Syslema, cmthort M. CUmente ccb Systema, 1. i. c. 1, q. 13 — 20, p. 40 — 5fi,
r.w//ifro, Uano viae, 1612. Vossius, X>< Aatura Gisbert ab Isendoom, Effata Philosophica,
Anium, 1. iv. Sive de Logica, c. ix. Pacius, In [Cent. i. § 51—63, p. 95 «i teq., ed. B&ventriae
i'o»j>Ayr»»ijafirogrm, p. 2, ed. Francof,1697. On 1643. — Ed.]
and Concrete or Spe-
cial.
C8 LOGIC. Lect. m
bent on an academical instructor, to do what in him lies to induce
h\^ pupils, by logical exercise, to digest what is presented to them
as an objective system into a subjective habit. Logic, therefore, in
both these relations belongs to us, and neither can be neglected
without compromising the utility of a course like the present.
If VII. In the second place, by relation to its application or
non-application to objects. Logic is divided
Par. VII. i-o^io. by -j^^Q Abstract or General, and into Concrete
relation to otrjects, is '
Abstract or General. or Spccial. The fomicr of thcsc is called,
by the Greek Aristotelians, SioXcktikt^ xi^P'-'^
irpay/iaTwv, and, by the Arabian and Latin
schoolmen, Logica docens; while the latter is denominated, by
the Greeks, SioAc/ctik^ Iv ^^pi^crei. kuI yv/JLvaaia vpayfidrbiv ; by the
Arabians and Latins, Logica utens.
Abstract Logic considers the laws of thought as potentially appli-
cable to the objects of all arts and sciences, but
as not actually applied to those of any; Con-
crete Logic considers these laws in their actual and immediate appli-
cation to the object-matter of this or that particular science. The
former of these, is one, and alone belongs to philosophy, whereas
the latter is as multiform as the arts and sciences to which it is
relative.^
This division of Logic does not remount to Aristotle, but it is
found in his most ancient commentator, Alexan-
Thi8 division of Logic ^^^ ^j^^ Aphrodisian, and, after him, in most of
lemonnts to Alexan- /-. i x • • * i i -n
der the Aphrodisian. ^^^^ Other Greek Logicians. Alexander illus-
trates the opposition of the logic divorced from
things (x<»>pis TT/aa-y/xaTwv, — rebus avulsa), to the logic applied to
things (ev xprjcTii. Kol yviivaaia. irpay/iaTtov, — rebus applicato), by a
simile. "The former, he says, "may be resembled to a geometrical
figure, say a triangle, when considered abstractly and in itself;
whereas the latter may be resembled to the same triangle, as con-
cretely existing in this or that particular matter : for a triangle con-
sidered in itseiris ever one and the same ; but viewed in relation to
its matter, it varies according to the variety of that matter ; for it
is different as it is of silver, gold, lead — as it is of wood, of stone,
etc.* The same holds good of Logic. General or Abstract Logic
1 See Krug, p. 27 [Logik^ § 10, Anm. — El).] ganum, p. 23. q. v. \ 2. " Alexander Aphro-
2 (Isendoorn, Ilffata, Cent. i. 55; Crellius, disiensis Logicatn rllam abjuuctam sirailein
hngoge Logica, p. 12.] The illustration is esse ait figura; gcomefrica;, utpote triaugulo,
('ally given by Balforeu8, CommtiUariiu in Or- dum iu M et per se speotatur; Logicam vero
Lect. m. LOGIC. 39
is always one and the same ; but as applied to this or to that object
of consideration, it appears multiform." So far Alexander. This
appearance of multiformity I may, however, add, is not real ; for
the mind has truly only one mode of thinking, one mode of reason-
ing, one mode of conducting itself in the investigation of truth,
whatever may be the object on which it exercises itself Logic
may therefore be again well compared to the
us ra e y com- authority of an universal empire — of an em-
pire governing the world by common laws. In
Kuch a dominion there are many provinces, various regions, and dif-
ferent praefectui'es. There is one praefect in Asia, another in Europe,
51 third in Africa, and each is decorated by different titles ; but each
governs and is governed by the common laws of the empire con-
fided to his administration. The nature of General Logic may
likewise be illustrated by another comparison. The Thames, for
instance in passing London, is a single river, ^is one water, — but is
there applied to many and different uses. It is employed for drink-
ing, for cooking, for brewing, for washing, for irrigation, for naviga-
tion, etc. In like manner. Logic in itself is one : as a science or
an art, it is single ; but, in its applications, it is of various and multi-
form use in the various branches of knowledge, conversant be it with
necessary, or be it with contingent matter. Or further, to take the
example of a cognate science, if any one were to lay down different
grammars of a tongue, as that may be applied to the different pur-
poses of life, he would be justly derided by all grammarians, indeed
by all men ; for who is there so ignorant as not to know that there
is but one grammar of the same language in all its various applica-
tions ? ^
Thus, likewise, there is only one method of reasoning, which all
the sciences indifferently employ ; and although men are severally
occupied in different pursuits, and although one is, therefore, entitled
a Theologian, another a Jurist, a third a Physician, and so on, each
cum rebus conjuuctam similem eidem tri- l See Rami Sch., p. 350, [P. Rami Scholce in
angulo huic aut illi materiae impresso. Nam Liberales Artes, Basileae, 1578. " Unus est Lu-
trianguli in se una est et eadem ratio; at pro tetiae Sequana, ad multos tamen usus et varios
varietate materia varia. Aliud enim est ar- accommodatus, lavaiidum, aquandum, vehen-
genteum, aliud aureum, aliud ligneum, lapi- dum, irrigandum, coquendum: sic una est
deum, aut plumbeum." The passage referred Logica, varii et multiplicis usus, in propoei-
to is probably one in the Commentary on the tione necessaria, probabili, captiosa; ars ta-
Prior Analytics, p. 2, ed. Aid. The distinction men una. Si Grammaticas tres aliquis inep-
itself, though not the illustration, is given tus nobis instituat, unam civilem, alteram
more exactly in the language of the text by agrestem, tertiam de vitis amborum, merito
some of the later commentators. See the In- rideatur a Grammaticis omnibus, qui unam
troductions of Ammonius to the Categories, Grammaticam norunt omnium ejusdem lin-
and of Philoponus to the Prior Analytics.— guae hominum communem."— Ed.]
JEd.]
40 LOGIC. Lect. UL
employs the same processes, and is governed by the same laws, of
thought. Logic itself is, therefore, widely differ-
Generai Logic is ent from the use — the application of Logic.
alone one; Special For Logic is astricted to no determinate matter.
Logic is manifold, and . n i .
part of the science in ^"^ ^^ extended to all that is the object of reason
which it is applied. and intelligence. The use of Logic, on the con-
trary, although potentially applicable to ev-
ei-y matter, is always actually manifested by special reference to
some one. In point of fact, Logic, in its particular applications, no
longer remains logic, but becomes part and parcel of the art or sci-
ence in which it is applied. Thus Logic, applied to the objects of
geometry, is nothing else than Geometry; Logic, applied to the
objects of physics, nothing else than Natural Philosophy. We have,
indeed, certain treatises of Logic in reference to different sciences,
which may be viewed as something more than these sciences them-
selves. For example : we have treatises on Legal Logic, etc ; but
such treatises are only introductions — only methodologies of the
art or science to which they relate. For such special logics only
exhibit the mode in which a determinate matter or object of sci-
ence, the knowledge of which is presupposed, must be treated, the
conditions which regulate the certainty of inferences in that mat-
ter, and the methods by which our knowledge of it may be con-
structed into a scientific whole. Special Logic is thus not a sin-
gle discipline, not the science of the universal laws of thought, but
a congeries of disciplines, as numerous as there are special sciences
in which it may be applied. Abstract or General Logic, on the con-
trary, in virtue of its universal character, can only and alone be
one; and can exclusively pretend to the dignity of an independent
science. This, therefore, likewise exclusively concerns us.
LECTURE IV.
INTRODUCTION.
LOGIC— III. ITS DIVISIONS — PURE AND MODIFIED.
In my last Lecture, after terminating the consideration of the seo
end introductory question, touching the Utilities of Logic, I pro-
ceeded to the third introductory question, —
Recapitulation.
What are the Divisions of Logic? and stated
to you the two most general classifications of this science. Of
these, the first is the division of Logic into Objective and Subjec-
tive, or Systematic and Habitual ; the second is its division into
General and Special, or Abstract and Concrete.
To speak only of the latter. Abstract or General Logic is logic
viewed as treating of the formal laws of thought, without respect
to any particular matter. Concrete or Special Logic is logic viewed
as treating of these laws in relation to a cei'tain matter, and in sub-
ordination to the end of some determinate science. The former of
these is one, and belongs alone to philosophy, that is, to the science
of the universal principles of knowledge ; the latter is as manifold
as the sciences to which it is subservient, and of which it, in fact,
constitutes a part, — viz., their Methodology. This division of
logic is given, but in diflTerent terms, by the Greek Aristotelians and
by the Latin schoolmen. The Greek division does not remount to
Aristotle, but it is found in his earliest expositor, Alexander of
Aphrodisias, and he was probably not the first by whom it was
enounced. It is into SiaXexTtK^ X'^P'^'* ""pay/xaTtov, Logica rebus avulsa,
that is, Logic merely formal. Logic apart from things; in other
words, abstract from all particular matter ; and SuxXc/crt/d) ev XPW^'-
Koi yvfivacTui irpayfidrtav, Logica rebus applicata, that is. Logic as used
and exercised upon things ; in other words, as applied to certain
special objects.
This distinction of Logic by the Greek Aristotelians seems alto-
gether unknown to modern logicians. The division of Logic by the
scholastic Aristotelians is the same with the preceding, but the
terms in which it is expressed are less precise and unambiguous.
6
42 LOGIC. Lect. it.
This division is into the Logica docens and JLogica utens. The
Logica dopens is explained as logic considered as an abstract the-
ory, — as a preceptiv6 system of rules, — " que tradit praecepta ; " —
the Logica uteris^ as logic considered as a concrete practice, — as an
application of these rules to use, — " quae utitur praeceptis." ^
This scholastic division of Logic into docens and utens has, I see,
been noticed by some of the more modern au-
nie division of Log- thors ; but it has been altogether mistaken, whicli
ica ocens, an og- .^ would not have been, had these authors been
ica utens, mistaken by ...
some modern authors. aware of the meaning in which the terms were
employed, and had they not been ignorant of
the more explicit expression of it by the Greeks. Thus the terms
docens and utens are employed by Wolf to mark a distinction not
the same as that which they designate in the scholastic logic, and
as the Wolfian distinction will not stand the test of criticism, the
terms themselves have been repudiated by those who were not
aware that there was an older and a more valid division which
they alone properly expressed.^ Wolf makes the Logica docens^
the mere knowledge of the rules : the Logica utens, the habit or
dexterity of applying them. This distinction of General and Spe-
cial logic, Wolf and the Wolfian logicians, likewise, denote by that
of Theoretical and Practical Logic." These terms are in themselves
by no means a bad expression of the distinction ; but those by whom
they were employed, unfortunately did not limit their Practical
Logic to what I have defined as Special, for under Practical they
included not only Special, but likewise Modified Logic, of which
we are now to speak.
Having explained, then, this primary division of Logic into Gen-
eral and Special, and stated that General Logic, as alone a branch
of philosophy, is alone the object of our consideration ; I proceed
to give the division of General Logic into two great species, or
rather parts, — viz., into Pure or Abstract, and Modified or Con-
crete.
% VIII. In the third place, considered by
Par. vrn. General reference to the circumstances under which
ZiOeic, divided into . . 'it-
Pure and Modified. it Can comc mto excrcisc by us, Logic —
Logic General or Abstract — is divided into
Pure and Modified ; — a division, however, which is perhaps
1 SmigUcii Logica, Disp. ii. q. vi. For scho- 3 Wolf, Philosophia Rationaiis, }§ 8, 9, 10, 12.
lastic authorities, see Aquinas, /n /K. Me/apA., — Ed. [Cf. Stattler, Sauter, and Mako,]
lect. iv. Scotus, Suptr Univ. Porphyrii, q. i. — [Stattler, Logica, ^ 18, p. 12; Sauter, Positiontt
Eiv Logica. P. I. and II, 1778; Instil. Leg., V 1. and
2 [As Krug] [see his Logtk. § 11, p. 30. Com- II. 1799; Paulus Mako do Kerek-Gede, Comr,.
pare Kant, Logik, Kinleitung, ii. — Kd.J Log. Iru-ait. P. I. and II., 4th edit., 1773. — Li)^
Lect. IV. LOGIC. 43
rather the distribution of a science into its parts than of a genus
into its species. Pure Logic considers the laws of thought
proper, as contained a priori in the nature of pure intelligence
itself. Modified Logic, again, exhibits these laws as modified
in their actual applications by certain general circumstances
external and internal, contingent in themselves, but by which
human thought is always more or less influenced in its mani-
festations.^
Pure Logic considers Thought Proper simply and in itself, and
apart from the various circumstances by which
it may be affected in its actual application. Hu-
man thought, it is evident, is not exerted except by men and indi-
vidual men. By men, thought is not exerted out of connection
with the other constituents of their intellectual and moral charac-
ter, and, in each individual, this character is variously modified by
various contingent conditions of different original genius, and of
different circumstances contributing to develop different faculties
and habits. Now, there may be conceived a sci-
Modifled Logic. ... • t i i ■>
ence, which considers thought not merely as
determined by its necessaiy and universal laws, but as contingently
affected by the empirical conditions under which thought is actually
exerted; — which shows what these conditions are, how they im-
pede, and, in general, modify, the act of thinking; and how, in fine,
their influence may be counteracted. This science is. Modified or
Concrete Logic. What I have called Modified
Nomenclature of -^ -^ j^ identical with what Kant and other
Modified Logic. f i t • i . t •
philosophers have denominated Applied Logic.
(Angewandte Logik, Logica applicata.y This expression I think
improper. For the term Applied Logic can
The term Applied only with propriety be. used to denote Special
^**'' or Concrete Logic ; and is, in fact, a brief and
excellent translation of the terms by which Special Logic was des-
ignated by the Greeks, as that cv ^(fyrja-ei koL yvixvaa-ia.Trpayfxa.Twv. And
so, in fact, by the Latin Logicians was the Greek expression ren-
dered. Let us consider the meaning of the term applied. Logic,
as applied, must be applied to something, and that something can
1 For distinction of reason in abstracto and quet,p. 236, [Sammlung der Sehriftenwelcht den
reason in concreto, grounding the distinction Logischen Calcul Herrn Prof. Ploucquets betreffrn,
of an Abstract (or Pure), and a Concrete (or Tubingen, 1773. — Ed.]
Modified) Logic, see Boyle's IVbris, iv. p. 164. 2 Kant, Logik, Einleitung ii.; Hoffbauer,
See also Lambert [Neues Organon, Dianoiolo- AnfangsgriXndt der Logik, H 17) 406; Krug,
/ne, i.— Ed], J 444, who says that the sciences Logik, Einleitung, i 11; Fries, System da
in general are only applied logics. Cf. Plouo- Logik, { 2. — £d.
44 LOGIC. Lect. IV.
only be an object or matter. Now, Special Logic is necess;jnly an
applied logic; therefore the term applied^ if given to what I would
call Modified Logic, would not distinguish Modified from Special
Logic. But further, the term apjplied as given to Modified Logic,
considered in itself, is wrong ; for in Modified Logic thought is no
more considered as actually applied to any particular matter than
in Pure Logic. Modified Logic only considers the necessary in
conjunction with the contingent conditions under which thought is
actually exertible; but it does not consider it as applied to one
class of objects more than to another; that is, it does not consider
it as actually applied to any, but as potentially applicable to all.
In every point of view, therefore, the term applied^ as given to
Modified Logic, is improper ; whereas, if used at
How properly em- ^11, it ought to be used as a synonym for special;
^'^^^ ' which I would positively have done, were it not
that, having been unfortunately bestowed by high authority on what
I have called Modified Logic, the employment of it to designate
a totally different distinction might generate confusion. I have
therefore refrained from making wie of the term. I find, indeed,
that all logicians who, before Kant, ever employed the expression
Applied Logic, employed it as convertible with Special or Concrete
Logic' In fine, it is to be observed that the terms pure and ap-
plied,*as usually employed in opposition in the Kantian philosophy,
and in that of Germany in general, are not properly relative and
correlative to each othrr. For jt>i^re has its proper correlative in
modified or mixed / applied its proper relative in unapplied^ that
is, divorced from, things, that is, abstract.
But passing from words to things, I may observe that it can be
questioned whether Modified or Concrete Logic
Modified Logic not ^^ entitled to the dignity of an essential part of
properly an essential -^ . . % f t •
part of Logic. Logic ixx general, far less of a coordmate species
as opposed to Pure or Abstract Logic. You are
aware, from what I have previously stated under the firet introduc-
tory question, that Logic, as convereant about a certain class of
mental phaenomena, is only a part of the general philosophy of
mind ; but that, as exclusively conversant about what is necessary
in the phsenoraena of thought, that is, the laws of thinking, it is
contradistinguished from Empirical Psychology, or that philosophy
of mind which is merely observant and inductive of the mental
phaenomena as facts. But if Modified or Concrete Logic be consid-
1 See B»)foreu8, [R. Baiforei CommentGriva separatam ; aliam rebua applioatam et cam iif
in Orgatium, q. v. 4 2, p. 22. '' Grxci . . coujunctam." — Ed.J
aliam dicuut Logicuin abjuuctam et & rebiu
LncT. IV. LOGIC. 45
ered either as a part or as a species of General Logic, this discrim-
ination of Logic, as the Nomology of thought, from Psychology, as
the Phaenomenology of mind, will not hold. For Modified Logic,
presupposing a knowledge of the general and the contingent phae-
nomena of mind, will thus either comprise Psychology within its
sphere, or be itself compiised within the sphere of Psychology.
But whichever alternative may be preferred, the two sciences are
no longer distinct. It is on this ground that I hold, that, in reality,
Modified Logic is neither an essential part nor an independent spe-
cies of General Logic, but that it is a mere mixture of Logic and
Psychology, and may, therefore, be called either Logical Psychol-
ogy or Psychological Logic.^ There is thus in truth only one
Logic, that is. Pure or Abstract Logic, liut while this, I think,
must be admitted in speculative rigor, still, as all sciences are only
organized for human ends, and as a general consideration of the
modifying circumstances which affect the abstract laws of thought
in their actual manifestations, is of great practical utility, I trust
that I shall not be regarded as deforming the simplicity of the sci-
ence, if I follow the example of most modern logicians, and add (be
it under protest) to Pure or Abstract Logic a part, or an appendix,
under the name of Modified Logic. In distributing the science,
therefore, into these two principal heads, you will always, I re-
quest, keep steadily in mind, that, in strict jn-opriety. Pure Logic
is the only science of Logic — Modified Logic being only a scien-
tific accident, ambiguously belonging either to Logic or to Psy-
chology.
This being understood, I now proceed to state to you the dis-
tribution of the general science into its parts ;
onspectus o t e ^^^ ^^ j^ -^ ^^ high importance that you now
Course of Logic , . . .
obtain a comprehensive view of the relation of
these parts to each other and to the whole which they constitute,
in order that you may clearly understand the point towai'ds which
we travel, and every stage in our progress, — I shall comprise this
whole statement in the following paragraph, which I shall endeavor
to make sufficiently intelligible without much subsequent illustra-
tion. That illustration, however, I will give in my next Lecture.
As this paragraph is intended to afford you a conspectus of the
ensuing Course, in so far as it will be occupied with Logic, I need
hardly say that yon will find it somewhat long. It is, however, I
believe, the only paragraph of any extent which I shall hereafter
be obliged to dictate.
1 [8ee Rkihter, p e7,[Oberdim Cfegetutand und den XTmfang dtr Logik, S 17, Leip8ic,18ffi.— Ed.J
46 LOGIC. Lect. J\.
% IX. Gkxei:ai, or Adstract Logic, we
par. IX Distribu- havG seeii, IS divided into two paits, — into
tjon of Logic into its t» a • m. nt /-vp^t
Pure and into Modified. Of these m
parts.
their order.
I. — Pure Logic may, I think, best be distributed upon the follow-
ing principles. We may think ; and we may think well. On
the one hand, the conditions of thinking do not involve the
conditions of thinking well ; but the conditions of thinking
well involve the conditions of thinking. Logic, therefore, as
the science of thought, must necessarily consider the conditions
of the possibility of thought. On the other hand, the end of
thought is not merely to think, but to think well ; therefore, as
the end of a science must be conformed to the end of its ob-
ject-matter. Logic, as the science of thought, must display not
only the laws of possible, but the laws of perfect, thinking.
Logic, therefore, naturally falls into two parts, the one of which
investigates the formal conditions of mere thinking ; the other,
the formal conditions of thinking well.
i. — In regard to the former: — The conditions of mere
thinking are given in certain elementary requisites; and that
part of Logic which analyzes and considers these, may be called
its Stoicheiology, or Doctrine of Elements. These elements
are either Laws or Products.
ii. — In regard to the latter, as perfect thinking is an end, and
as, the elementary means being supposed, the conditions of an
end are the ways or methods by which it maybe accomplished,
that part of Logic which analyzes and considere the methods
of perfect thinking, may bo called its Methodology, or Doctrine
of Method.
Thus Pure Logic is divided into two parts, — into Stoichei-
ology, or the Doctrine of Elements, and Methodology, or the
Doctrine of Method. Of these in their order.
Logical Stoicheiology, or the doctrine conversant about the
elementary requisites of mere thought, I shall divide into two
parts. The first of these treats of the Fundamental Laws of
thinking; in other words, of the universal conditions of the
thinkable — Noetic — Nomology. The second treats of the
laws of thinking, as governing the special functions, faculties,
or products of thought, in its three gradations of Conception ;
or, as it is otherwise called. Simple Apprehension, — Judg-
ment, and Reasoning, — Diaonetic — Dynamic.
This second part of Stoicheiology will, therefore, fall into
i
Lic'JT. IV. LOGIC. 4 1
three subordinate divisions corresponding to these several de-
■ grees of Conception, Judgment, and Reasoning. So much for
the Doctrine of Elements.
Logical Methodology, or the doctrine conversant about the
regulated ways or methods in which the means of thinking
are conducted to their end of thinking well, is divided into as
many parts as there are methods, and there are as many meth-
ods as there are different qualities in the end to be differently
accomplished. Now; the perfection of thought consists of three
virtues, — Clear Thinking, Distinct Thinking, and Connected
Thinking ; each of these virtues is accomplished by a distinct
method ; and the three methods will consequently afford the
division of Logical Methodology into three parts.
The first part comprises the method of Clear Thinking, or
the doctrine of Illustration or Definition.
The second part comprises the Method of Distinct Thinking,
or the doctrine of Division.
The third part comprises the Method of Concatenated or
Connected Thinking, or the Doctrine of Proof.
These parts are only, however, three particular applications
of Method; they, therefore, constitute each only a Special
Methodology. But such methodology, or union of methodolo-
gies, supposes a previous consideration of method in general, in
its notion, its species, and its conditions. Logical Methodology
will therefore consist of two parts, of a General and of a Spe-
cial, — the Special being subdivided, as above stated. So much
for the distribution of Pure Logic.
11. — Modified Logic falls naturally into Three Parts.
The First Part treats of the nature of Truth and Error, and
of the highest laws for their discrimination, — Alethiology.
The Second treats of the Impediments to thinking, with the
Means of their Removal. These impediments arise, 1°, from
the Mind ; 2°, From the Body ; or, 3°, From External Circum-
stances. In relation to the Mind, these impediments originate
in the Senses, in Self-Consciousness, in Memory, in Associa-
tion, in Imagination, in Reason, in the faculty of Language, in
the Feelings, in the Desires, in the Will. In relation to the
Body, they originate in Temperament, or in the state of Health.
In relation to External Circumstances, they originate in the di-
versities of Education, of Rank, of Age, of Climate, of Social
Intercoui'se, etc.
The Third Part treats of the Aids or Subsidiaries of think-
48 LOGIC. / Lect. IV.
ing; and thinking is aided either, 1°, Through the Acquisition,
or, 2", Through the Communication, of Knowledge.
The former of these subsidiaries (the acquisition of knowl-
edge) consists, 1°, Of Experience (and that either by ourselves
or by others) ; 2®, Of Generalization (and this- through Induc-
tion and Analogy) ; and, 3°, Of Testimony (and this either Oral
or "Written). Under this last head falls to be considered the
Credibility of Witnesses, the Authenticity and Integrity of
Writings, the Rules of Criticism and of Interpretation.
The latter of these subsidiaries, the Communication of Knowl-
edge, is either One-sided or Reciprocal. The former consists
of Instruction, either Oral or Written ; the latter of Conversa-
tion, Conference, Disputation.
So much for the distribution of Modified Logic.
Tabular view of the On the Opposite page is a general tabular view
nivisions of Logic. of the Divisions of Logic now given.
The fourth and fifth questions of the Introduction would now
fall to be considered, — viz.. What is the History
IV. The History of and what is the Bibliography, of Logic ? Were
''"""'■ I writing a book, and not ffivinf]r a coui-se of Lec-
This question post- ° . ° .
j.y^gjj tures upon Logic, I would certainly consider these
questions in the introduction to the science ; but
I would do this with the admonition that beginners should pass
these over, and make themselves first of all familiar with the doc-
trines of which the science is itself the complement. For why ?
The history of u science is a narrative of the order in which its
several parts have been developed, and of the contributions which
have been made to it by difierent cultivators ; but such a narrative
necessarily supposes a previous knowledge of the contents of the
science, — a knowledge which is identical with a knowledge of the
science itself. It is, therefore, evident, that a history of Logic can
only be proposed with advantage to those who are already in some
degree familiar with Logic itself; and as, in a coui-se like the present,
I am bound to presume that you are not as yet conversant with the
science, it follows that such a history cannot with any propriety be
attempted in the commencement, but only towards the conclusion,
of the Lectures. •
In regard to the fifth question, — What is the Bibliography or
Literature of Logic ? — the same is true, in so
p^'j^ j^ far as a knowledge of the books written upon a
science is correlative to a knowledge of its his-
tory. At the same time, nothing could be more unprofitable than
Lect. IV.
LOGIC.
49
A TABULAR VIEW
DIVISIONS OF LOaiC.
'1. Noetic,—
Nomology.
i. Stoicheiology.
1 2. Diaonetic
Dynamic.
' a.Conception,
' b. Judgment.
c. Reasoning.
Pure.
ii. Methodology.
General
OR
Abstract "
Logic.
<n. Modified.
Gear Thinking.— Definition
or Illustration.
'Distinct Thinking. — 2. Di-
vision.
Connected Thinking. — 3.
Probation or Proving.
1. The Mind.
i. Truth and Error — Cer-
tainty and Illusion.
u. Impediments to Think-\ 2- The Body.
ing, with Remedies.
These Impediments/
arise from . . . y3. Exteraal Circumstances.
1. The Acquisition of Knowl-
edge
iii. Aids or Subsidiaries to ,
Thinking — through
2. The Communication of
Knowledge, etc.
50 LOGIC. Lect. rv-
for me to recite to you a long series of works to which you have not
access, by authors of whom you probably never heard, often in lan-
guages which few of you understand. In the present stage of your
studies, it is not requisite that you should know of many books, but
that you should read attentively a few ; — non inulta sed miiltura. —
I shall therefore adjourn, at least, the consideration of the question,
What in general are the principal books on the science of Logic? —
simply recommending to you a few, not absolutely the best, but such
as you can most easily procure; such as are in languages which most
of you can read, and which are of such a character as maybe studied
with most general advantage.
Of works in our own language, as those most accessible and most
intelligible to all, there are unfortunately hardly
General notice of ■!_• -l t i ^ ^ •^ •^•
^ . any which 1 can recommend to you as exhibiting
•works on Logic. •' _ _ •' ®
the doctrines of Logic, either in purity or com-
pleteness. The Logic of Watts, of Duncan, and others, ai'e worth
reading, as books, but not as books upon Logic. The Elements of
Logic by Dr. Whately is, upon the whole, the one best entitled to
your attention, though it is erroneous in various respects, and imper-
fect in more. The abridgment of this work by Hinds contains what
of the original is most worthy of study, in the commencement of a
logical education. In French, there are sundry works deserving of
your attention (Dnmiron,^ Delariviere) ;- but the only one which I
would at present earnestly recommend to your study, is the cele-
brated Port Royal Art of Thinking, — L^ Art de Penser^ — an anony-
mous work, but the authors of which were the two distinguished
Jansenists, Arnauld and Nicole. It has been frequently reprinted ;
and there is recently a stereotyped edition, by Hacht tte, of Paris,
which can easily be procured. There are more than one trans-
lation of the work into Latin, and at least two English vei-sions, both
bad.''
In Latin there is a very elegant compend of Logic by the late
illustrious Daniel Wyttenbach, of Leyden. Besides the Dutch edi-
tions, which are handsome, there is a cheap reprint published by
Professor Maas, of Halle, who hns, however, ventured on the unwar-
rantable liberty of silently altering the text, besides omitting what
he did not consider as ;ibsoliitely indispensable for a text-book. Tliis
work can be easily ])rocured. There is also in Latin a system of
1 Cows de PhUosophie, t. iv.; Logique, Paris, burgh, 1850; 2d edition, 1851. In the Iiitro-
1837. — Ed. duction to this version will be found on
2 Logique Clnnsiqur, Paris, 1829. — Ed. account of the various editions and transla-
3 A third and far superior translation ha.s tions of the work. — Ed.
•ubsequently appeared by Mr. Baynes, E^in-
Lect. IV. LOGIC. 61
Logic by Genovesi, under the title, Genxiensis Ars Logico-critica.
This work is, however, extremely rare even in Italy, and it was
many years before I was able to procure a copy. There was an edition
of this work published in Germany in 1760, at Augsburg, but the
impression seems to have been small, for it also is out of print. The
Italian Logic of Genovesi has, however, been repeatedly reprinted,
and this, with the valuable addition of Romagnosi, is easily obtained.
Of the older writers on Logic in Latin, the one I would principally
recommend to you is Burgersdyk — Burgersdicius. His Institu-
tiones Logicce is not a rare work, though, as there are no recent
editions, it is not always without trouble to be obtaloed.
LECTURE V.
PURE LOGIC.
PART I. - STOICHEIOLOay.
SECTION I. NOETIC — ON THE FUNDAMENTAL LAWS OP
THOUGHT — THEIR CONTENTS AND HISTORY.
Having terminated our consideration of the various questions of
which the Introduction to Loeic is composed,
Stoicheiology. , , , . , . , , * ,
we proceed to the doctrines which make up the
science itself and commence the First Great Division of Pure Logic
— that which treats of its elementary or constituent processes, —
Stoicheiology. But Stoicheiology was again divided into two parts,
— into apart which considered the Fundamental Laws of Thought
in general, and into a part which considered these laws as applied
to and regulating the special function of Thought in its various
gradations of Conception, Judgment, and Reasoning. The title,
therefore, of the part of Logic on which we are about to enter is, —
Pure Logic^ Part I. Stoicheiology — Section I. N^oetic. On the
Fundainental Laws of Thought.
Before, however, descending to the consideration of these laws, it
is necessary to make one or two preliminary
_, . ^ . , statements touching the character of that thought
Thought in general. _ * _ _ ®
of which they are the necessary conditions; and,
on this point, I give, in the first place, the following paragraph :
^ X. Logic considers Thought, not as the operation of
thinking, but as its product ; it does not
treat of Conception, Judgment, and Rea-
soning, but of Concepts, Judgments, and Reasonings.
I have already endeavored to give you a general knowledge of
what is meant by thought. You are aware that
loug as e o - ^i^j^ term is, in relation to Lotjio, employed in
ject of Logic. . . ' .....
its strictest and most limited signification, —
viz., as the act or product of the Discursive Faculty, or Faculty of
Lect. V. LOGIC. 53
Relations; but it is now proper to consider, somewhat more closely,
the determinate nature of this process, and the special point of
view in which it is regarded by the logician.
In an act of thinking, there are thi-ee things which we can dis-
criminate in consciousness, — 1°, There is the
The subject, form, tiji^king subject, that is, the mind or ego,
and matter of thought. & J ' ' & »
which exerts or manifests the thought; 2°,
There is the object about which we think, which is called the matter
of thought; and, 3°, There is a relation between subject and ob-
ject of which we are conscious, — a relation always manifested in
some determinate mode or manner; — this is the/brm of thought.
Now, of these three. Logic does not consider
Thought as the ob- either the first or the second. It takes no ac-
ject respectively of ^ ^ i . t />,i i
Psychology and of couut, at Icast no du'cct account, of the real
Logic. subject, or of the real object, of thought, but is
limited exclusively to the form of thought. This
has been already stated. But, again, this form of thought is con-
sidered by Logic only in a certain aspect. The form of thought
may be viewed on two sides or in two relations. It holds, as has
been said, a relation both to its subject and to its object, and it may
accordingly be viewed either in the one of these relations or in the
other. In so far as the form of thought is considered in reference
to the thinking mind, — to the mind by which it is exerted, — it is
considered as an act, or operation, or energy ; and in this relation it
belongs to Phaenomenal Psychology. Whereas, in so far as this
form is considered in reference to what thought is about, it is con-
sidered as the product of such an act, and, in this relation, it be-
longs to Logic. Thus Phaenomenal Psychology treats of thought
proper as conception, judgment, reasoning; Logic, or the Nomology
of the understanding, treats of thought proper as a concept, as a
judgment, as a reasoning. Whately, I have already shown you,
among other errors in his determination of the object-matter of
Logic, confounds or reverses this; for he proposes to Logic, not
thought considered as a product, but reasoning alone ; and that, too,
considered as a producing operation. He thus confounds Logic
with Phaenomenal Psychology.
•Be it, therefore, observed, that Logic, in treating of the formal
laws of thought, treats of these in reference to thought considered
as a product ; that is, as a concept, a judgment, a reasoning ;*whereas
Psychology, as the Phaenomenology of mind, considei-s thought as
the producing act, that is, as conception, judgment, reasoning.
(You here see, by the way, the utility of distinguishing concept and
conception. It is unfortunate that we cannot also distinguish more
^4 LOGIC. Lect. V.
precisely judgment and reasoning as producing acts, from a judg-
ment and a reasoning as products.)
Par. XI. Thought a ^ ^^' Thouglit, as the knowledge of
mediate and complex one thing in relation to another, is a medi-
ate and complex cognition.
cognition.
The distinctive peculiarity of thinking in general is, that it in-
volves the cognition of one thing by the cognition of another. All
thinking is, therefore, a mediate cognition ; and
is thus distinguished from our knowledge in per-
ception, extern.al and internal, and in imagination ; in both of which
acts we are immediately cognitive of the object, external or internal,
presented in the one, and of the object, external or internal re-
presented in the other. In the Presentative and Representative
Faculties, our knowledge is of something considered directly and in
itself; in thought, on the contrary, we know one object only through
the knowledge of another. Thus in perception, of either kind, and
in imagination, the object known is always a single determinate ob-
ject; whereas in thought, — in thought pi'oper, — as one object is
only known through another, there must always be a plurality of
objects in every single thought. Let us take an example of this,
in regard to the simplest act of thought. When I see an individ-
ual,— say Bucephalus or Highflyer, — or when I represent him in
imagination, I have a direct and immediate apprehension of a cer-
tain object in and through itself, without reference to aught else.
But when I pronounce the term ITorse, I am unable either to per-
ceive in nature, or to represent in imagination, any one detei-rainate
object corresponding to the word. I obtain the notion con*espond-
ing to this word, only as the result of a comparison of many per-
ceptions or imaginations of Bucephalus, Highflyer, Dobbin, and
other individual hoi^es ; it, therefore, contains many representations
under it, has reference to many objects, out of relation to which it
cannot possibly be realized in thought ; and it is in consequence of
this necessity of representing (potentially at least) a plurality of
individual objects under the notion horse, that it obtains the denom-
ination concept, that is, something taken up or apprehended in con-
nection with something else. This, however, requires a further ex-
plicatiorf. When we perform an act of thought, of positive thought,
this is done by thinking something, and we can think anything only
by thinking it as existing; while, again, we cannot think a thing to
exist except in certain determinate modes of existence. On the
other hand, when we perform an act of negative thought, this is
Lect. V. LOGIC. 55
done by thinking something as not existing in this or that determi-
nate mode, and when we think it as existing in no determinate
mode, we cense to think it at all ; it becomes a notliing, a logical
nonentity {non-ens Logicum).
It being thus understood that thought can only be realized by
thinking something; it being further understood that this some-
thing, as it is thought, must be thought as existing ; and it being
still further understood that we can think a thing as existing only
by thinking it as existing in this, that, and the other determinate
maimer of existence, and that whenever we cease to think some-
thing, something existing, something existing in a determinate man-
ner of existence, we cease to think at all ; — this, I say, being under-
stood, it is here proper to make you, once for all, acquainted with
the various terms by which logicians designate the modes or man-
ners of cogitable existence. I shall therefore comprise these in
the following paragraph :
1 XII, When we think a thing, this is done by conceiving
it as possessed of certain modes of being,
Par. XII. The vari- or qualitics, and the sum of these qualities
OU8 terms by which cOUStitUtCS itS COHCept OV UOtion (votjua, ev-
the modes of cogi- ^
table existence are VOVOL, CTTlVOta, COHCeptum, COnCCptUS^ notio).
designated. ^g thcsc qualities or modes (irow-np-e';, qual-
itates, modi) are only identified with the
thing by a mental attribution, they are called attributes {Ka-rf-
yopovfjiO'CL, attributa) ; as it is only in or through them that we
say or enounce aught of a thing, the)'' are called predicates^
predicables, and predicaments^ or categories^ these words being
hei"e used in their more extensive signification (Ac-yo/ieva x«pA
KaTrjyoplai, KarqyoprjfiaTa KaTrjfyopoviJieva, prcedicata^ prcedicahilia^
prmdicainenta) ; as it is only in and through them Ihat we lec-
ognize a thing for what it is, they are called notes, signs, marks,
characters {notee, signa, characteres, discrimina) ; finally, as it
is only in and through them that we become aware that a thing
is possessed of a peculiar and determinate existence, they are
called 2>f'operties, differences, detertninations (^proprietates, de-
term,inationes). As consequent on, or resulting fi-om, the exist-
ence of a thing, they have likewise obtained the name of con-
sequents (ETro/ttcva, cotisequentia, etc.). What in reality has no
qualities, has no existence in thought, — it is a logical nonen-
tity; hence, e converso, the scholastic aphorism, — non-entis
nulla sunt prmdicaZa. What, again, has no qualities attributed
50 LOGIC. Lect. V.
to it, though attributable, is said to be indetermined (dlSiopioroi',
indeterminatum) ; it is only a possible object of thought.^
This paragraph, which I have dictated that you might be made
once for all acquainted with the relative terms in
ExpiicaUon. What ^gg among logicians, requires but little explaua-
is involved in think- . _ , i , • i ,
j ^^ ^^.^^ tion. 1 may state, however, that the mind only
thinks an object by separating it from others ;
that is, by marking it out or characterizing it ; and in so far as it
does this, it encloses it within certain fixed limits, tliat is, determines
it. But if this discriminative act be expressed in words, I predicate
the marks, notes, characters, or determinations of the thing ; and if,
again, these be comprehended in one total thought, they constitute
its concept or notion. I£, for example, I think of Socrates as son of
SqphroniscuSy as Athenian^ as philosopher, as pug-nosed, these are
only so many charactei's, limitations, or determinations, which I pre-
dicate of Socrates, which distinguish him from all other men, and
together make up ray notion or concept of him.
But as thought, in all its gradations of conception, judgment, and
reasoning, is only realized by the attribution of
The attribution in- certain qualities or characters to the objects of,
Tolred in thought is i . , i . ., . .
recuiated by laws. ^^' ^bout which we thmk ; SO this attribution is
regulated by laws, which render a great part of
this process absolutely necessary. But wlien I speak of laws and of
their absolute necessity in relation to thouglit.
What is meant by a ^ ^^^^ ^^^ gupp^ge t^^t ^hegg j^^s and that
law as applicable to " j.-, • .1 u ^ • j
free intelligence. necessity are the same in the world 01 mind as
in the world of matter. For free intelligences,
a law is an ideal necessity given in the form of a precept, which we
ought to follow, but which we may also violate if we please ;
whereas, for^the existences which constitute the universe of nature,
a law is only another name for those causes whicli operate blindly
and universally in producing certain inevitable results. By law of
thought, or by logical necessity, we do not, therefore, mean a physi-
cal law, such as the law of gravitation, but a general precept which
we are able certainly to violate, but which if we do not obey, our
whole process of thinking is suicidal, or absolutely null. These laws
are, consequently, the primary conditions of the possibility of valid
thought, and as the whole of Pure Logic is only an articulate
development of the various modes in which they are applied, their
consideration in general constitutes the first chapter in an orderly
1 [Schulze, Logik, 1, 13. RiSsling, p. 63.] [DU Lehrtn der reinen Logik, Ulin, 1826. CC
Krug, Logik, S 16. — Ed.]
Lect. V. LOGIC. 57
system of the science. Now, in explaining to you this subject,
the method I shall pursue is the following : I
Order of considera- ^^xaW, first of all, State in general the number and
tion of the fundamen- . .-, /. ^i i i • -,
tai laws of thought. Significance of the laws as commonly received ;
I shall then more particularly consider each of
these by itself and in relation to the others ; then detail to you their
history; and, finally, state to you my own views in regard to their
deduction, number, and arrangement.
% XIII. The Fundamental Laws of Thought, or the condi-
tions of the thinkable, as commonly received,
Par. XIII. Pun- arcfour: — 1. The Law of Identity; 2. The
damental Ijaws of , ,
Thought. Law of Contradiction ; 3. The Law of Ex-
clusion or of Excluded Middle ; and, 4. The
Law of Reason and Consequent, or of Sufiicient Reason.
Of these in their order.
% XIV. The principle of Identity (principium Identitatis)
expresses the relation of total sameness in
Par. XIV. Law of which a coucept stands to all, and the rela-
Identity. ^ ^ . '
tion of partial sameness in which it stands
to each, of its constituent characters. In other words, it de-
clares the impossibility of thinking the concept and its charac-
ters as reciprocally unlike. It is expressed in the formula A is
Ay or Az=A; and by A is denoted every logical thing, every
product of our thinking faculty, — concept, judgment, reason-
ing, etc.^
The principle of Identity is an application of the principle of the
absolute equivalence of a whole and of all its
parts taken together, to the thinking of a thing
by the attribution of constituent qualities or characters. The concept
of the thing is a whole, the characters are the parts of that whole.^
This law may, therefore, be also thus enounced, — Everything is
equal to itself, — for in a logical relation the thing and its concept
coincide ; as, in Logic, we abstract altogether from the reality of the
thing which the concept represents. It is, therefore, the same
whether we say that the concept is equal to all its characters, or
that the thing is equal to itself.^
The law has, likewise, been expressed by the formula — In the
1 [Schulze, Logik, § 17. Gerlach, Logik, i 2 See Schulze, iogiA, p. 32-3. — Ed.
37.] Cf. Krug-, Logik, § 17. — Ed. 3 See Krug, Lo^k, p. 40. — Ed.
8
58 LOGIC. Lect. V.
predicate, the whole is contained explicitly, which in the subject is
contained implicitly. It is also involved in the axiom — Nota notcn
est nota rei ipsius}
The logical importance of the law of identity lies in this — that
Its logical importance '^^ ^^ ^he principle of all logical affirmation and
—The principle of all definition. An example or two may be given to
logical affirmation and illustrate this.
'^''^""'•'"•- 1. In a concept, which we may call Z, the
characters a, 5, and c, are thought as its constituents; consequently,
the concept, as a unity, is equal to the characters
This illustrated. , ^ I „ , j ^-r-.,^
taken together — Z = (a + o + c). If the former
be affirmed, so also is the latter ; therefore, Z being {a-^h + c) is a,
is J, is c. To take a concrete example : The concept man is a
complement made up of the characters, 1°, substance, 2°, material,
S°, organized^ 4", animated^ 5°, rational^ 6°, of this earth ; in other
words man is substance, is material, is organized, is animated, is ra-
tional. JSeitig, as entering into every attribution, may be discharged
as affording no distinction.
2. Again, suppose that, in the example given, the character a is
made up of the characters I, m, n, it follows, by the same law of
Identity, that Z = a = (^ m, n) is I, is m, is n. The concept man
contains in it the character animal, and the character animal con-
tains in it the characters corporeal, organized, limn{f, etc.
The second law is the principle of Contradiction or Non-contra-
diction, in relation to which I shall dictate the following paragraph :
% XV. When an object is determined by the affirmation of
a certain character, this object cannot be
Contradiction. thought to be the samc when such charactei"
is denied of it. The impossibility of this is
enounced in what is called the principle of Contradiction
(principiuTn Contradictionis seu HepiignatiticB). Assertions
concerning a thing are mutually contradictory, when the one
asserts that the thing possesses the character which the other
asserts that it does not. This law is logically expressed in the
fonnula — What is contradictory is unthinkable. A = not
A=zO, or A~A=0.
Now, in the first place, in regard to the name
Its propername. n ^ • ■, • \ ^ i i
ot this law. It may be observed that, as it en-
joins the absence of contradiction as the indispensable condition of
1 See Kant, Logik, p. 40. — £o.
Li:CT. V. LOGIC. 59
thought, it ought to be called, not the Law of Contradiction, but
the Law of Non-contradiction, or of non-repugnantia}
This law has frequently been enounced in the formula — It is
impossible that the same thing can at once be and
not be ; but this is exposed to sundry objections.
It is vague, and therefore useless. It does not indicate whether a
real or a notional existence is meant ; and if it mean the former,
then is it not a logical but a metaphysical axiom. But even as a
metaphysical axiom it is imperfect ; for to the expression at once
{simul) must be added, in the same place, in the same respect, etc?
This law has likewise been expressed by the formula — Contra-
dictory attributes cannot be united in one act of consciousness. But
this is also obnoxious to objection. For a judgment expresses as
good a unity of consciousness as a concept. But when I judge, that
round and square are contradictory attributes, there 'are found in
this judgment contradictory attributes, but yet a unity of con-
sciousness. The formula is, therefore, vaguely and inaccurately
expressed.
The logical import of this law lies in its being the principle of all
logical negation and distinction.
The principle of all r^^^ j.^^^ ^f Identity and the law of Contra-
logical negation and -,. . i- -, • n i •
distinction. diction are coordinate and reciprocally relative,
'"~~ancnTertTier can be educed as second from the
other as first ; for in every such attempt at derivation, the supposeoT
secondary law is, in fact, always necessarily presuppose<L^^rhese
are, in iact, one and the same law, di^ring only by a positive and
negative expression.
In relation to the third law, take the following paragraph :
t XVI. The principle of Excluded Third or Middle — viz.,
between two contradictories (p'inciphan
Excluded Middir " JBxclusi MedH vel Tertii), enounces that
condition of thought which compels us, of
two repugnant notions, which cannot both coexist, to think
either the one or the other as existing. Hence arises the gen-
eral axiom — Of contradictory attributions, we can only affirm
one of a thing ; and if one be explicitly affirmed, the other is im-
plicitly denied. A either is or is not. A either is or is not B.^
By the laws of Identity and Contradiction, I am warranted to
1 Compare Krug, Logik, § 18. — Ed. 3 This is shown more in detail by Hoffbauer
2 Compare the criticism of Kant, Kritik d.r. ^nfaas^grHnde der Logik, § 23. -- Ed.
v., p. 134, ed. Kosenkranz. — Ed. 4 See Schulze, Xog^i, § 19; — Ed.
60 LOGIC. Lect. V.
conclude from the truth of one contradictory proposition to the
falsehood of the other, and by the law of Ex-
Logicai significance ^j^^^^ Middle, I am warranted to conclude from
of this law.
the falsehood of one contradictory proposition to
the truth of the other. And in this lies the peculiar force and import
of this last principle. For the logical significance of the law of Ex-
cluded Middle consists in this, that it limits or shuts in the sphere
of the thinkable in relation to affirmation ; for it determines, that,
of the two forms given in the laws of Identity and Contradiction,
and by these laws affirmed as those exclusively possible, the one or
the other must be affirmed as necessary.
The law of Excluded Middle is the principle of Disjunctive Judg-
ments, that is, of judgments iu which a plurality
The principle of Dis- of judgments are contained, and which stand in
janctive Judgments. , . i i • i i /v. •
\ such a reciprocal relation that the affirmation of
one is the denial of the other.
I now go on to the fourth law.
% XVII. The thinking of an object, as actually character-
ized by positive or by negative attributes, is
Par. xvn. Law of not left to the caprice of Understanding —
Sufficient Beason. or ^^^ faculty of thought ; but that faculty
of Beason and Conse- "^ .
quent. must be necessitated to this or that deter-
minate act of thinking by a knowledge of
something different from, and independent o^ the process of
thinking itself. This condition of our understanding is ex-
pressed by the law, as it is called, of Sufficient Reason {princi-
pium Rationis Siifficientis) ; but it is more properly denomi-
nated the law of Reason and Consequent {principiurn Mationis
et Consecutionis). That knowledge by which the mind is
necessitated to affirm or posit something else, is called the logi-
cal reason, ground, or antecedent; that something else which
the mind is necessitated to affirm or posit, is called the logical
consequent; and the relation between the reason and conse-
quent, is called the logical connection or consequence. This
law is expressed in the formula — Infer nothing without a
ground or reason.*
Relations between The relations between Reason and Conse-
Beason and Conse- quent, when comprehended in a pure thought,
**"*"*■ are the following :
1. When a reason is explicitly or implicitly given, then there must
1 See Scliulzc, Losik, § 19, and Krug, Logik, § 20. — Ei>.
Lect. V. LOGIC. 01
exist a consequent; and, vice versa, when a consequent is given,
there must also exist a reason.
2. Where there is no reason there can be no consequent ; and,
vice versa, where there is no consequent (either implicitly or explic-
itly) thei-e can be no reason. That is, the concepts of reason and of
consequent, as reciprocally relative, involve and suppose each other.
The logical significance of the law of Reason and Consequent lies
in this, — That in vii'tue of it, thought is consti-
^IIJjcBi^significance ^^^^^^ -^^^^ ^ g^^.j^^ ^f ^^^^ ^^j indissolubly Con-
nected ; each necessarily inferring the other.
Thus it is that the distinction and opposition of possible, actual and
necessary mattei*, which has been introduced into Logic, is a doc-
trine wholly extraneous to this science.
I may observe that "Reason is something different from Cause,
and Consequent something different from Effect;
Reason and Conse- ^hough cause and effect, iu SO far as they are
quent, and Cause and . ^ . . ,
Effect. conceived m thought, stand to each other m the
relation of reason and consequent. Cause is
thus thought of as a real object, which affords the reason of the
existence of another real object, the effect ; and effect is thought of
as a real object, which is the consequent of another real object, the
cause. Accordingly, every cause is recognized in thought as a rea-
son, and every effect is recognized in thought as a consequent ; but
the converse is not true, that every reason is really considered a
cause, and every consequent really considered an effect. We must,
therefore, carefully distinguish mere reason and mere consequent,
that is, ideal or logical reason and consequent, from the reason
which is a cause and the consequent which is an effect, that is, real
or metaphysical reason and consequent.
" The expression logical reason and consequent refers to the mere
synthesis of thoughts; whereas the expression
Logical and Meta- metaphysical reason and consequent denotes the
physical Reason and , . ^ . tt i •
r, . real connection ot existences. Hence the axiom
Consequent.
of Causality, as a metaphysical principle, is es-
sentially different from the axiom of Reason and Consequent, as a
logical principle. Both, however, are frequently confounded with
each other; and the law of Reason and Consequent, indeed, for-
merly found its place in the systems of Metaphysic, while it was
not, at least explicitly, considered in those of
Generality of the Logic. The two terms condition and conditioned
terms Condition and i "^ -i , ,^ ^ ^- \, j.x. e
„ ... , happily express at once the relations both oi
reason and consequent, and of cause and effect.
A condition is a thing which determines (negatively at least) the
62 LOGIC. Lect. V.
existence of another; the conditioned is a thing whose existence is
determined in and by another. If used in an ideal or logical signifi-
cation, condition and conditioned import only the reason in conjunc-
tion with its consequent ; if used in a real or metaphysical sense,
they express the cause in connection with its effect." '
I have now, in the prosecution of our inquiry into the fundamen-
tal laws of logical thinking, to say a few words
History of the de- in regard to their History, — their history being
veiopment of the fun- ^^^ narration of the order in which, and of the
damental Laws of . i i
Thought. philosophers by whom, they were articulately
developed.
Of the first three laws, which, from their intimate cognition, may
not unreasonably be regarded as only the three
The law of Identity gj^jgg ^^ phascs of a single law, the law of Iden-
last developed in the . i r> • i i n
order of time *^*y» which Stands farst in the order of nature,
was indeed that last developed in the order of
time ; the axioms of Contradiction and of Excluded Middle having
been long enounced, ere that of Identity had been discriminated
and raised to the rank of a coordinate principle. I shall not, there-
fore, now follow the order in which I detailed to you these laws,
but the order in which they were chronologically generalized.
The principles of Contradiction and of Excluded Middle can both
be traced back to Plato, by whom they were
The principles of euounccd and frequently applied ; though it was
,*"! "? «.!T, "" ^ not till long after, that either of them obtained
eluded Middle can be ...
traced back to Plato. ^ distinctive appellation. To take the principle
of Contradiction first. This law Plato frequently
employs, but the most remarkable passages are found in the Phcedo^
in the Sophista^ and in the fourth and seventh books of the Reiyublic?
This law was, however, more distinctively and
Law of Contradic- emphatically enounced by Aristotle. In one
tion emphatically , « , x • •/•
enoanced by Aristotle. V^^^^^ "^ says : « It IS manifest that no one can
conceive to himself that the same thing can at
once be and not be, for thus he would hold repugnant opinions,
1 Kmg, Lo^iA, pp. 62, 63. This exposition For, in as much as this principle is not mate-
of the law of Reason and Consequent does rial, it is only a derivation of the three for
not represent the Author's latest view. In a mal laws; and in as much as it is material, it
note to the Discussions, p. 160 (where a similar coincides with the principle of Causality, and
doctrine had been maintained in the article is extra-logical." The Laws of Thought,
as originally published), he says: "The logi- properly so called, are thus reduced to three,
cal relation of Reason and Consequent, as more —those of Identity, Contradiction, rad Ex-
than a mere corollary of the law of Noneon- eluded Middle. — Ed.
fra(fJf/ion in its three phases, is, I am confident „„ „, ,„„ „ ,. ^_ _
of proving, erroneous." And again, in the /> See PA^rfo, p. 103; 5i>pA»«a, p. 252; Repub-
same work, p. 603 : " The principle of S.ffi- '"' *''• P' *^' "*'• P" ^- " ^-
cient Reason should be excluded from Logic. 3 Metaph., I. iii. (iv.) c. 8.
Lect. V. LOGIC. 63
and subvert the reality of truth. Wlierefore, all who attempt to
demonstrate, reduce everything to this as the ultimate doctrine ; for
this is by nature the principle of all other axioms." And in several
passages of his Metaphysics^^ in his Prior Analytics^- and in his
Posterior Analytics,^ he observes that "some had attempted to
demonstrate this pririciple, — an attempt which betrayed an igno-
rance of those things whereof we ought to i-equire a demonstration,
and of those things whereof we ought not : for it is impossible to
demonstrate everything; as in tliis case, Ave must regress and re-
gress to infinity,' and all demonstration would, on that supposition,
be impossible."
Following Aristotle, the Peripatetics established this law as the
highest principle of knowledge. From the
• J u- ! !"^^ ^•" Greek Aristotelians it obtained the name by
ics the highest priuci- _ ^ •'
pie of knowledge. Ob- which it has Subsequently been denominated,
tained its name from the principle, ov law, OY axiom, of contradiction^
the Greek Aristote- (--^^'^^a T^5 (lvTi<^(io-£a>s). This name, at least, is
found in the Commentaries of Ammonius and
Philoponus, where it is said to be " the criterion which divides truth
from falsehood throughout the universe of exist-
g g ' ence."* The schoolmen, in general, taught the
same doctrine; and Suarez even says, that the
law of contradiction holds the same supremacy among the princi-
ples of existence.^
After the decline of the Aristotelian philosophy, many controver-
sies arose touching the truth, and still more touching the primitive
or Axiomatic character, of this law. Some main-
Controversies re- tained that it was indemonstrable ; others that it
specting the truth and ,,, •-, - .... ,,
character of this law. ^ould be proved, but provcd only andn-ectly by a
reductio ad absurdum; while others, again, held
that this could be directly done, and that, consequently, the law of
Contradiction was not entitled to the dignity of a first principle.*
L. iii. c. 4. T^f ovToiv koL fxyj ovtwv StatptT rh iptvSos kcH
2 L. ii. c. 2. T^y aXri^elav. In Anal. Post., 1, i. c. xi. f 30
" ^- '• *'• 2- b. — Ed. [Cf. Augustinus Niphus Suessanus,
4 For the name, see Ammonins, In De Inter- /„ ^„ai. Post., p. 88, ed. Paris, 1540.]
pnt., Comment., p. 153 b. ed. Aid. Venet. 1546.
Philoponus, In Anal. Pr., p. 13 b, 38 b, ed. ^ ^^^ [Alstedius, 4rt,«m Liberallum Syslema
Vcnet. 1535. In Anal. Post., p. 30 b, ed. AM. <^^'°'' P" l'*' " Cognitio a priori est principi-
Venet. 1534. The language quoted in the text "'■"™ ' '''^" *!"'* *«"''" '^"*'" ^"""^ ^mposs,b,U
is nearly a translation of Ammonius /n Cat.g.. "' i'lnn esse et non esse. . . . Consule Metaph.,
,,„ ■„ \ V / 1 , , ' Suarezii : — 'Hoc, inquam, tenet primatum
p. 140 a. H fiev yap Kara^acrts kcu airdd)- . , ... j- •„ » r»„.,„ ,-„*„,
.. , , inter pnncipia cognoscendi, sicut Deus inter
affis ad iirl ttuutwu rwv ovriav Koi m/J ovtwv principia esseudi.' "]
S.oipe? Tb d-yija^s Ka\ rh vj/eDSos. Ammon- 6 Cf. Suarez.2>«>pwta«(on« JMe/apAysir«, Disp.
ius is followed by Philoponus, who says,— iii.^3._ED. [Alstedius, Encyc?o/j«rfio. 1. iii.,
Ti 8i rrts avricpd(rea>s a^i<i>/xa eirl iravTuv ftkv Archelogia, c. vii. p. 80]
64 LOGIC. , Lbct. V.
In like manner, its employment was made a further matter of
controversy. Finally, it was disputed whether it were an imme-
^ii^tCj^ jiatiA'e,_or « ^tor/^^timi of intelligence; or whether it
were an a posteriori and adventitious generalization from experi-
ence. The latter alternative, that it was only an induction, was
maintained by Locke.^ This opinion was, how-
^*"^^" ever, validly refuted bv Leibnitz, who showed
Leibnitz. , . . \ . ,
that it IS admitted the moment the terms of its
enunciation are understood, and that we implicitly, follow it even
when we are not explicitly conscious of its dictate.^ Leibnitz, in
some parts of his works, seems to identify the principles of Iden-
tity and Contradiction ; in others, he distinguishes them, but educes
the law of Identity out of the law of Contradiction.^ It is needless
to pursue the subsequent history of this principle, which in latter
times has found none to gainsay the necessity
Its truth denied by ^^^ universality of its truth, except among those
modern absolutists. .1 , 1 • /-i
philosophers who, m Germany, have dreamt that
man is competent to a cognition of the absolute : and as a cognition
of the absolute can only be established through positions repug-
nant, and, therefore. On logical principles, mutually exclusive, they
have found it necessary to start with a denial of the fundamental
laws of thought; and so, in their effort to soar to a philosophy
above logic and intelligence, they have subverted the conditions of
human philosophy altogether. Thus Schelling and Hegel prudently
repudiated the principles of Contradiction and Excluded Middle as
having any application to the absolute ; * while again those philoso-
phers (as Cousin) who attempt a cognition of the absolute without
a preliminary repudiation of the laws of Logic, at once involve
themselves in contradictions, the cogency of which they do not deny,
and from which they are wholly unable to extricate themselves.*
•
1 'EsM.y^ B i. ch. ii. § 4. —Ed. pointed out by the latter in his GeicAiehie der
2 Noiiveaiix K'isnis, li. i. ch. i §4. — Ed. Philosophic, {Werke, xv. p. 598.) — Ed. [On
3 Compare Tlicodicie, ( 44, Monadologie,^ 31, rejection of the Logical Laws, by Schelling,
with Nouvtaux Essais, 1. i. ch. i. § 10; 1. iv. IIegeI,etc.,see Baclimann, Uber die Philosophie,
ch. ii. § 1. — Ed. tneiner Zeic, p. 218, ed. Jena, 1816. Bolzano,
4 See Schelling, Voin Ich als Princip drr Phi- WssenschaftsUhre, iv., Logik, § 718. Sigwart,
loxophif, § 10; Hegel, Logik, b. ii. c. 2; Encyk- Logilc, 5 58, p. 42, ed. 1835. Herbart, De Priu-
lopdrJie, § 115, 119. Schelling endeavors to cipio Logieo Exclusi Medii inter ContrtuJictoria
abrogate the principle of Contradiction in nan negligendo, Gofting, 1833. Hartenstein,
relation to the higher philosophy, by assnm- Df Meihodn Phitosophia Logica Lfgihux adxtrin-
ing that of Identity; the empirical antago- g'ti'lti, Jinibiis non terminanda, Lipsix, 1836.
nism between ego and non-ego being merged Ou the logical and metaphysical significance
in the identity of the absolute ego. Hegel of the principle of Contradiction, see Plat-
regardsbofh principles alike as valid only for ner, P/til. Aph.. I. ^ 673, and Kant, Kritik d.
the finite Understanding, and as innpplicnble rtinen IWnunft. p. 191. ed. 1790.]
to the higher processes of the Reason. This « See the Author's criticism of Cousin, Dir
difference between the two philosophers is cussions, p. I tt seq. — Ed.
Lect. V. LOGIC. 65
But this by the way, and on a subject which at present you cannot
all be supposed to understand.
The law of Excluded Middle between two contradictories re-
mounts, as I have said, also to Plato, though the
Law of Excluded ^econd AlciUades, the dialogue in which it is
Middle. ' °
most clearly expressed, must be admitted to be
spurious.^ It is also in the fragments of Pseudo-Archytas, to be
' found in Stobaeus.^ It is explicitly and emphat-
Expiicitiy enounced .^j^jj enounced by Aristotle in many passages
by Aristotle. '' *^ ^ i o
both of his Metaphysics (1. iii. (iv.) c. 7.) and
of his Aoialytics, both Prior (1. i. c. 2) and Posterior (1. i. c. 4). In
the first of these, he says : " It is impossible that there should exist
any medium between contradictory opposites, but it is necessary
either to afiimi or to deny everything of everything." And his ex-
pressions are similar in the other books. Cicero says "that the
foundation of Dialectic is, that whatever is;
enounced is either true or false." This is from
his Academics (1. ii. c. xxix.), and there are parallel passages in his
Topics (c. xiv.) and his De Oratore (1. ii. c. xxx.). This law, though i
universally recognized as a principle in the Greek Peripatetic school, ,
and in the schools of the middle ages, only received the distinctive •
appellation by which it is now known at a comparatively modern ;
date.^ I do not recollect having met with the term principium eX'-
clusi medii in any author older than the Leib—
nitzian Baumgarten,* though Wolf* speaks of
the exclusio medii inter contradictoria.
The law of Identity, I stated, was not explicated as a coordinate-
principle till a comparatively recent period. The.
Law of Identity. earliest author in whom I have found this done,
Antonius Andreas.
is Antonius Andreas, a scholar of Scotus, who-^
flourished at the end of the thirteenth and beginning of the four-
teenth century. The schoolman, in the fourth book of his Com-
mentary of Aristotle's Metaphysics^^ — a commentary which is fullC
of the most ingenioiis and original views, — not only asserts to the-
law of Identity a coordinate dignity with the law of Contradiction,.
1 Second Alcibiadef, p. 139. See also So- nseus Elementa Loglea, 1. ii. c. 14, [p. 172, ed.
phista, p. 250. — Ed. 1603. " Contradicentium usus explicatur uno •
2 Ecloga. 1. ii. c. 2, p. 158, ed. Antwerp, 1575; axiomate : — Contradicentia non possunt de •
Part ii, torn. 1, p. 22, ed. Heeren. Cf. Simpli- eodem simul esse vera; et necessarium est.
cius, In Arist. Categ., pp. 97, 103, ed. Basil, contradicentium alterum cuilibet rei conven-
1551. — Ed. • ire, alterum non convenire." — Ed.]
3 Lex contradictoriamm, principium cotUradi- ^ j^taphysica, § 10. - Ed.
eentium (sc. propositionum), as used in the
schools, included the law of Contradiction * On/oiog-io, H 62, 53.
and the law of Excluded Middle. See Moli- 6 Quaestio v. p. 21 a, ed. Venet., 1513. — Ed»
66 LOGIC. Lect. V.
but, against Aristotle, he maintains that the principle of Identity,
and not the principle of Contradiction, is the one absolutely firat.
The formula in which Andreas expressed it was Ens est ens. Sub-
sequently to this author, the question concerning the relative prior-
ity of the two laws of Identity and of Contradiction became one
much agitated in the schools ; though there were also found some
who asserted to the law of Excluded Middle this supreme rank.*
Leibnitz, as I have said, did not always distin-
guish the principles of Identity and of Contra-
diction. By Wolf the former was styled the principle of Certainty,
{principium Certiticdinis) -^^ but he, no more
than Leibnitz himself, sufficiently discriminated
between it and the law of Contradiction. Tiiis was, however, done
by Baumgarten, another distinguished follower
Baumgarten. ^t-i-^ in ^ • • • i ^
01 Leibnitz,'^ and irom him it received the name
of the principle of Position, that is, of Affirmation or Identity,
{princiinum Positionis sive Identitqtis), — the name by which it is
now universally known. This principle has found greater favor, in
the eyes of the absolutist philosophers, than those of Contradiction
and Excluded Middle. By Fichte and Schelling
Fichte and Schei- -^ j^jjg ^jggQ placed as the primary principle of all
jj* , philosophy.* Hegel alone subjects it, along witl>
the other laws of thought, to a rigid but fall.i-
cious criticism ; and rejects it along with them, as belonging to that
lower sphere of knowledge, which is conversant only with the rela-
tive and finite.*
The fourth law, that of Reason and Conso-
Law of Reason and quent, which Stands apart by itself from the othc:-
n equen . three, was, like the laws of Contradiction and
Secognized by Plato '
and Aristotle. Excluded Middle, recognized by Plato.® He lays
it down as a postulate of reason, to admit noth-
ing without a cause ; and the same is frequently done by his
. „ , scholar Aristotle.^ Both, however, in reference
,.,»., to this principle, employ the ambis^uous term
cause (alria aiTiov). Aristotle, indeed, distin-
guishes the law of Reason, as the ide.'il principle of knowledge (apxrj
I [Alex, de Ales, Tn Arist. Metapk., iv. t. 9.] » Metaphysica. i 11. — Ed.
Compare Suarez, Disp. Mftaph., Disp. iii. § 3. * See Fichte, Cruiuilage der gtsammten Ww-
Alexander professes to agree with Aristotle stnxckq/UUhre, } I. Schelling, Vom IcA, § 7. -
in Riving the first place to the principle of Ed.
Contradiction, but, in fact, he identifies it 5 See above, p. 64, note 4. — Ed.
with that of Excluded Middle, de ptovis affix- 6 PMUbus, p. 26. — Ed.
•natio vel nrgatio. — ElD. 7 E. g. Atuil. Post., ii. 16; Phys , ii. 3; Metapk^
3 Ontologia, } 65, 288. —Ed. i. 1. 3; Rktt., Ii. 23. — Ed.
Lect. V. LOGIC. 67
T^s yvoKTeo)?, principium cognoscendi), from the real principle cf
Production, (a/3X7 ""^ ycveo-coj?, principium Jiendi, — prificipium c,^
sendi)} By Cicero, the axiom of reason and
J!^°^1"\. , consequent was, in like manner, comprehended
The Schoolmen. ^ » if
under the formula, nihil sine causa," — a formuL;
adopted by the schoolmen ; although they, after Aristotle, distin-
gnished under it the ratio essendi, and the ratio cognoscendi.'
In modern times, the attention of philosophers was called to this
law of Leibnitz, who, on the two principles of
Leibnitz called at- Rcason and ^of^oiitrgdtction"; Tounded the whole"
tention to Law of Suf- -t*.^ n i ' i m — i"" ■» tt i" " i "; —
ficient Reason. edigce of his philosophy.^ IJnder the latter
law, as I have mentioned, he comprehended,
however, the principle of Identity ; and in the former he did not
sufficiently discriminate, in terms, the law of Causality, as a real
principle, from the law of Reason, properly so called, as a formal or
ideal principle. To this axiom he gave various denominations, —
now calling it the principle of Determining Reason, now the princi-
ple of Sufficient Reason, and now the principle of Convenience or
Agreement {convenientia) ; making it, in its real relation, the ground
oF all existence ; in its TcleaT7 tEe ground of all positive knowledge.
Orrtfaissubject there was a celebratelTcohtroversy between Leibnitz
and^Dr. Samuel Clarke, — a controversy on this, as on other points,
eminerftly worthy ot your stu'dy. Tlie documents in which this con-
troytfrsy is containetl, w/'61'e published in the English edition under
the title, ^1 collection of Papers which passed between the late learned
Mr. Leihnitz and Dr. Clarke, in the years 1715 and 1716, relating
to the Principles of Natural Philosophy and Religion, London,
1717.*
Wolf, the most distinguished follower of Leibnitz, employs the
formula — "Nothing is without a sufficient rea-
Wolf. , . . . , , • • , .
son why it is, rather than why it is not ; that is,
if anything is supposed to be {ponitur esse), something also must
be supposed, whence it may be understood why the same is rather
than is not."^ He blames the schoolmen for confusing reason
{ratio) with cause (causa) : but his censure equally applies to his
master Leibnitz, as to them and Aristotle ; for all of these philoso-
phers, though they did not confound the two principles, employed
ambiguous terms to denote them.
1 Metaph.,iv.{v.)l. — Ed. or Identity is assumed as the foundation ol
2 De Divinatione, ii. c. 28. — Ed. all mathematics and that of Sufficient Ilea-
3 See Tkcodicce, § 44. Monadologie, §§ 81,32. son as the foundation of natural philosopliy
--Ed. —Ed.
* See especially, Leibnitz's Second Letter, 5 See Fischer's Logik, [§ 59, p- 38, ed. 1888
D. 20, in which the principle of Contradiction Compare Wolf, Ontologia, §§ 70, 71. — Ed.]
68 LOGIC. Lect. r.
The Leibnitian doctrine of the universality of the law of Suffi-
cient Reason, both as a principle of existence
Discussion regard- ^^^ ^f thought, cxcitcd much discussion among
ing the Leibnitzian , ,., , ^' ^ -i p /^
doctrine of the law of the philosophers, more particularly of Germany.
Sufficient Reason. In the earlier half of the last century, some con-
troverted the validity of the principle, others
attempted to restrict it.^ Among other arguments, it is alleged, by
the advocates of the former opinion, if the principle be admitted,
that everything must have a sufficient reason why it is, rather than
why it is not, — on this hypothesis, error itself will have such a rea-
son, and, therefore, must cease forthwith to be error.^
Many philosophers, as Wolf and Baumgarten, endeavored to
demonstrate this principle by the principle of Contradiction ; while
others, with better success, showed that all such demonstrations
were illogical.^
In the more recent systems of philosophy, the universality and
necessity of the axiom of Reason has, with other logical laws, been
controverted and rejected by speculators on the absolute.*
1 As Feuerlin and Daries. See Bachmann, S [Kiesewetter, AUgemeine Logik, P. i. p. 67] ;
Logik, p. 66, Leipsig, 1828 ; Cf. Degerando, compare Lectures on Metaphysics, ii. pp. 396,
Hist. Comp. des Syst. de PhU., t. ii. p. 146, ed. 397, notes. —Ed.
1804. — Ed. * [On principle of Double Negation as
S See Bachmann, Logik, p. 66. With the another law of Thought, see Fries, Logik, i
foregoing history of the laws of Thought, 41, p. 190; Calker, Denldehre oder Logik und
oompare the samb author, Logik, § 18-31.— Dialtktik, § 166, p. 463; Beneke, Lehrbuchder
Ed. Logik, } 64, p. 41.]
LECTURE VI.
STOICHEIOLOOY.
SECTION L — NOETIC.
THE FUNDAMENTAL LAWS OF THOUGHT — THEIR CLASSIFI-
CATION AND IMPORT.
Having concluded the Introductory Questions, we entered, in
our last Lecture, upon our science itself. The
api u a 1 . g^^^ ^^^ ^^ Pure Logic is the Doctrine of Ele-
ments, or that which considers the conditions of mere or possible
thinking. These elements are of two kinds, — they are either the
fundamental laws of thought as regulating its necessary products, or
they are the products themselves as regulated by those laws. The
fundamental laws are four in number, — the law of Identity, the law
of Contradiction, the law of Excluded Middle, the law of Reason
and Consequent.^ The products of thought are three, — 1°, Con-
cepts or Notions ; 2°, Judgments ; and, 3°, Reasonings. In our last
Lecture, we considered the first of these two parts of the doctrine
of elements, and I went through the general explanation of the con-
tents and import of the four laws, and their history. Without re-
capitulating what was then stated, I shall now proceed to certain
general observations, which may be suggested in relation to the four
laws.
And, first of all, I may remark, that they naturally fall into two
classes. The first of these classes consists of
General observations . , t • ^
in relation to the four the three principles of Identity, Contradiction,
ftindamentai laws of and Excluded Middle ; the second comprehends
fhought. These fall ^he principle of Reason and Consequent alone.
into two classes. mi • i •/» • • /. t -i i i j-/i«
Ihis classification is founded both on the aitter-
ent reciprocal connection of the laws, and on the difierent nature of
their results.
In the first place, in regard to the difiference of connection be-
tween the laws themselves, it is at once evident that the first three
1 See, however, p. 62, note 1.— Ed.
70 LOGIC. Lect. VL
st:uicl in a far more proximate relation to each other than to the
fourth. The first three are, indeed, so inti-
This classification mately Connected, that though it has not even
founded, 1°, On the ^^^^ attempted to carry them up into a higher
difference of connec- ... , , .
tion between the laws pnnciple, and though the various and contradic-
themseives. tory endeavofs that hav^ been made to elevate
one or other into an antecedent, and to degrade
others into consequents, have only shown, by their failure, the im-
})ossibility of reducing the three to one; still so intimate is their
connection, that each in fact supposes the othei-s. They are like the
three sides of a triangle ; not the same, not reducible to unity, eacli
pretending with equal right to a prior consideration, and each, if
considered first, giving in its own existence the existence of the
other two. This intimacy of relation does not subsist between the
principle of Reason and Consequent and the three other laws;
they do not, in the same necessary manner, suggest each other in
thought. The explanation of this is found in the diflTerent nature
of their results; and this is the second subject of our consideration.^
In the second place, then, the distinction of the four laws into
two classes is not only warranted by the differ-
2°, On the diiiference ^nce of their mutual dependence in thought, but,
of the end wliich the ,., . i ., t«. « ., -, i • i ^i
likewise, b^- the dinerenco oi the end winch the
two classea severally ' •'
accomplish. two classes severally accomplish. For the first
three laws not only stand apart by themselves
(forming, as it were, a single principle viewed in three diffeient
aspects), but they necessitate a result very different, both in kind
and in degree, from that determined by the law of Reason and Con-
sequent. The difference in their result consists in this, — whatever
violates the laws, whether of Identity, of Contradiction, or of Ex-
cluded Middle, we feel to be absolutely impossible, not only in
thought but in existence. Thus we cannot attribute even to Om-
nipotence the i)Ower of making a thing different from itseU^ of mak-
ing a thing at once to be and not to be, of making a thing neither
to be nor not to be. These three laws thus detennine to us the
sphere of possibility and of impossibility; and this not merely in
thought but in reality, not only logically but metaphysically. Very
different is the result of the law of Reason and Consequent. This
principle merely excludes from the sphere of positive thought what
we cannot comprehend ; for whatever we comprehend, that through
which we comprehend it is its reason. What, therefore, violates the
1 For a later development of the Author's philoeophjr as regards the diatinetion bere indfr
cated, see JHset$ssiom, p. 602 ttstq.—' £d.
Lrct. VI. LOGIC. 71
law of Reason and Consequent merely, in virtue of this law becomes
:i logical zero; that is, we are compelled to think it as unthinkable,
but not to think it, though actually non-existent subjectively or in
thought, as therefore actually non-existent objectively or in reality.
And why, it may be asked, does the law of Reason and Consequent
not equally determine the sphere of general possibility, as the laws
of Identity, Contradiction, and Excluded Middle ? Why are we to
view the unthinkable in the one case not to be equally impossible in
reality, as the unthinkable in the other? Some philosophers have,
on the one hand, asserted to the Deity the power of reconciling con-
tradictions ; ^ while, on the other, a greater number have made the
conceivable in human thought the gauge of the
Two counter opin- possible in existence. What warrants us, it may
ions regar ing e y^^ asked, to Condemn these opposite proced-
hmits of objective ' rr r
possibility. ures as equally unphilosophical ? In answer to
this, though the matter belongs more properly
to Metaphysic than to Logic, I may say a few words, which, how-
ever, I am aware, cannot, by many of you, be as yet adequately
understood.
To deny the universal application of the first three laws, is, in
fact, to subvert the reality of thought ; and as this subversion is
itself an act of thought, it in fact annihilates itself
When, for example, I say that A is, and then say that A is not,
by the second assertion I sublate or take away
The respective what, by the first assertion, I posited or laid
spheres of the two down ; thought, in the one case, undoing by
classes or" the laws of . ■, • ^ i • i i i /«•
thought defined and negation what, m the other, it had by afhrma-
iiiustrated. tion done. But when it is asserted, that A
To deny the univer- existing and A non-existing are at once true,
sal application of the ^j^^^ ^^^^ ^j^j^ .. ^ j^ implies that negation
first three laws, is to in*- -i
subvert the reality of ^^d affirmation correspond to nothing out of the
thought. mind — that there is no agreement, no disa-
greement between thought and its objects ; and
this is tantamount to saying that truth and falsehood are merely
empty sounds. For if we only think by affirmation and negation,
and if these are only as they are exclusive of each other, it follows,
that unless existence and non-existence be opposed objectively in
the same manner as affirmation and negation are opposed subjec-
tively, all our thought is a mere illusion. Thus it is, that those who
would assert the possibility of contradictions being at once true,
in fact annihilate the possibility of truth itself, and the whole signifi*
cance of thought.
1 Compare Le Clerc, Logiea, p. ii. c. 3.~-£i>.
7^ LOGIC. Lect. Tl;
But this is not the case when we deny the universal, the absolute
application of the law of Reason and Conse-
But this is not in- quent. When I say that a thing may be, of
voived in the denial of ^hich I cannot conceivc the possibility (that is,
the universal applica- , • • -^ ^i ^ />
tionoftheiaw fRe ^ conceiving it as the consequent or a certain
son and Consequent. reason), I Only Say that thought is limited ; but,
within its limits, I do not deny, I do not sub-
Aert, its truth. But how, it may be asked, is it shown that thought
is thus limited? How is it shown that the inconceivable is not an
index of the impossible, and that those philosophers who have era-
ployed it as the criterion of the absurd, are themselves guilty of
iibsurdity ? This is a matter which will come under our considera-
tion at another time and in its proper place ; at
This law shown in present it will be sufficient to state in general
general not to be the ^^^^ ^^^ hypothesis which makes the thinkable
measure of objective /» i m i i • i ■
possibility. ^^^ measure of the possible, brings the principle
of Reason and Consequent at once into collision
with the three higher laws, and this hypothesis itself is thus reduced
at once to contradiction and absurdity. For if we take a compre-
hensive view of the phaBnomena of thought, we shall find that all
that we can positively think, that is, all that is within the jurisdic-
tion of the law of Reason and Consequent, lies between two oppo-
site poles of thought, which, as exclusive of each other, cannot, on
the principles of Identity and Contradiction, both be true, but of
which, on the principle of Excluded Middle, the one or the other
mast. Let us take, for example, any of the general objects of our
knowledge. Let us take body, or rather, since body as extended is
included under extension, let us take extension itself, or space.
Now, extension alone will exhibit to us two pairs of contradictory
inconceivables, that is, in all, four incomprehensibles, but of which,
though all are equally unthinkable, and, on the liypothesis in ques-
tion, all, therefore, equally impossible, we are compelled, by the law
of Excluded Middle, to admit some two as true and necessary.
Extension, then, may be viewed either as a whole or as a part ;
and, in each aspect, it affords us two incogitable contradictories.
1°, Taking it as a whole : — space, it is evident.
By reference to Ex- j^jjjg^ gitiigj. fee limited, that is, have an end, a
^Ij^j^' ' circumference; or unlimited, that is, have no
end, no circumference. These are contradictory
suppositions ; both, therefore, cannot, but one must, be true. Now
let us try positively to comprehend, positively to conceive, the pos-
sibility of either of these two mutually exclusive alternatives. Can
we represent or realize in thought extension as absolutely limited ?
Lect. vl logic. 73
in other words, can we mentally hedge round the whole of space,
conceive it absolutely bounded, that is, so that beyond its boundary
there is no outlying, no surrounding, space?
Space or extension rp^-^ jg impossible. Whatever compass of space
as absolutely bounded, . ,. . . t .
unthinkable. '^^ ^'^Y inclose by any limitation oi thought, we
shall find that we have no difficulty in transcend-
ing these limits. Nay, we shall find that we cannot but transcend
thera ; for we are unable to think any extent of space except as
within a still ulterior space, of which, let us think till the powers of
thinking fail, we can never reach the circumference. It is thus
impossible for us to think space as a totality, that is, as absolutely
bounded, but all-containing. We may, therefore, lay down this first
extreme as inconceivable. We cannot think space as limited.
Let us now consider its contradictory ; can we comprehend the
possibility of infinite or unlimited space? To
Space unlimited in- suppose this is a direct contradiction in terms ;
conceivable, as con- . ; .
tradictory. ^^ ^^ ^^ Comprehend the incomprehensible. We
think, we conceive, we comprehend, a thing, only
as we think it as within or under something else; but to do this of
the infinite is to think the infinite as finite, which is contradictory
and absurd.
Now, here it may be asked, how have we then the word infinite f
How have we the notion which this word ex-
Objection from the presses? The answer to this question is con-
name and notion of .,.,,... „ .. -
the intinite obviated. ^^ined in the distinction of positive and negative
thought. We have a positive concept of a
thing, when we think it by the qualities of which it is the comple-
ment. But as the attribution of qualities is an
Distinction of posi- affirmation, as affirmation and negation are rela-
tive and negative ,. , , . , i • t
, ^ ^ ,. tives, and as relatives are known only in and
thought and notion. ' •'
through each other, we cannot, therefore, have a
consciousness of the affirmation of any quality, without having at
the same time the correlative consciousness of its negation. Now,
the one consciousness is a positive, the otlier consciousness is a neg-
ative notion. But, in point of fact, a negative notion is only the
negation of a notion ; we think only by the attribution of certain
qualities, and the negation of these qualities and of this attribution,
is simply, in so far, a denial of our thinking at all. As affirmation
always suggests negation, every positwe notion must likewise sug-
gest a negative notion ; and as languag^e Js the reflex of thought,
the positive and negative notions are expres^sed by positive and
negative names. Thus it is with the infinite. The finite is the only
object, of real or positive though\, ; it is thai alone which we think
10
74 LOGIC. Lect. VL
by the attribution of determinate characters ; the infinite, on the
contrary, is conceived only by the thinking away of every character
by which the finite was conceived; in other
The Infinite ex- words, wc conccivc it Only as inconceivable.
presse y negative rj^j^.^ relation of the infinite to the finite is
terms.
shown, indeed, in the terras by which it is ex-
pressed in every language. Thus in Latin, infinitum ; in Greek,
ttTTcipov ; in German, unendlich ; in all of which original tongues the
word expressive of the infinite is only a negative expression of tlie
finite or limited. Thus the very objection from the existence of a
name and notion of the infinite, when analyzed, only proves more
clearly that the infinite is no object of thought; that we conceive
it, not in itself, but only in congelation and contrast to the finite.
The indefinite is, however, sometimes confounded w4th the infin-
ite ; though there are hardly two notions which,
The Indefinite and ^ithout being Contradictory, differ more widely.
Infinite, — how distin- mi • i /» • i i • • i • /» •
jgjjg^ ihe indefinite has a subjective, the infinite an
objective relation. The one is merely the nega-
tion of the actual apprehension of limits, the other the negation of
the possible existence of limits.
But to return whence we have been carried, it is manifest that
we can no more realize the thought or concep-
Space as bounded tjon of infinite, unbounded, or unlimited space,
»nd space as unbound- i\^^^ ^r^ ^an realize the conception of a finite or
>d being two incon- '■
^eivabie contradicto- absolutely bouuded spacc. But these two incon-
ries, the law of Reason ceivables are reciprocal contradictories, and if
>nd Consequent can- ^,g ^^^ unable to Comprehend the possibility of
*ot, therefore, form .^ i -i i xi • • \ c -tk
'he criterion of objec- ^^^hcr, while, howcvcr, ou the principle of Ex.
Jive possibility. cluded Middle one or other must be admitted,
the hypothesis is manifestly false, that proposes
the subjective or formal law of Reason and consequent as the crite-
rion of real or objective possibility.
It is needless to show that the same result is given by the exper-
iment made on extension considered as a part,
This further shown ^^ divisible. Here, if we attempt to divide ex-
by reference to Exten- ... , ■, ■,^ ■ ■, i
^on 2° As a Part. tcusiou lu thought, wc shall neither, on the one
hand, succeed in conceiving the possibility of an
absolute minimum of space, that is, a minimum ex hi/pothesi ex-
tended, but which cannot be conceived as divisible into parts, nor,
on the other, of cari-ying on this division to infinity. But as these
are contradictory opposites, they again afford a similar refutation of
the hypothesis in question.
But the same conclusion is reached by simply considering the
Lect. vl logic. 75
law of Reason and Consequent in itself. This law enjoins — Think
nothing without a reason why we must think it;
3^ By reference to ^j^^t is, think nothing except as contained in,
the law of Reason and , ,
Consequent itself. ^^ cvolved out of, Something else which we
already know. Now, this reason, — this some-
thing else, — in obedience to this very law, must, as itself known,
be itself a consequent of some other antecedent ; and this antece-
dent be again the consequent of some anterior or higher reason ;
and so on, ad infinitum. But the human mind is not possessed of
infinite powers, or of an infinite series of reasons and consequents ;
on the contrary, its faculties are very limited, and its stock of knowl-
edge is very small. To erect this law, therefore, into a standard of
existence, is, in fact, to bring down the infinitude of the universe to
the finitude of man, — a pi'oceeding than which nothing can be im-
agined more absurd. The fact is, that the law
The laws of Reason ^f Reason and Consequent can, with the law of
!l°d^udbreTT higher ^'^"^^ ^"^ ^^^^t' the law of Substaucc and
principle. Phsenomenon, etc., be, if I am not mistaken, all
reduced to one higher principle, — a principle
which explains from the very limitation of the human mind, from
the very imbecility of its powers, a great variety of phaenomena,
which, from the liberality of philosophers, have obtained for their
solution a number of positive and special principles. This, how-
ever, is a discussion which would here be out of place.^ What, how-
ever, has been said may sufiice to show that,
Summary statement ^yi^^g ^^e first three laws of thought are of an
of the spheres of the , , _ . , t n i • t
laws of thought. absolute and universal cogency, the fourth is only
of a cogency relative and particular ; that, while
the former determine the possibility, not only of all thought, but of
all real knowledge, the latter only regulates the validity of mediate
or reflective thought. The laws of Identity, Contradiction and Ex-
cluded Middle are, therefore, not only logical but metaphysical prin-
ciples, the law of Reason and Consequent a logical principle alone ; a
doctrine which is, however, the converse of what is generally taught.
I proceed, now, to say a few words on the general influence which
these laws exert upon the operations of think-
The general iufln- ing. These Operations, however various and
ence which the forego- multiform they may seem, are so governed in all
ing laws exert on the . .„., , ,. ,
operations of think- ^hcir manifestations by the preceding laws, that
ing. no thought can pretend to validity and truth
which is not in consonance with, which is not
governed by, them. For man can recognize that alone as real and
1 Se« DUeussions, p. 609. — Eo.
76 LOGIC. Lect. VI
assured, which the laws of his understanding sanction ; and he can.
not but regard that as false and unreal, which these laws condemn.
From this, however, it by no means follows that what is thought in
conformity to these laws, is therefore true; for the sphere of thought
is far wider than the sphere of reality, and no inference is valid
fi-om the correctest thinking of an object to its actual existence.
While these laws, therefore, are the highest criterion of the non-
reality of an object, they are no criterion at all of its reality ; and
they thus stand to existence in a negative and not in a positive rela-
tion. And what I now say of the fundamental principles of thought
in general, holds equally of all their proximate and special applica-
tions, that is, of the whole of Logic. Logic, as I have already ex-
plained, considering the form alone of thought to the exclusion of
its matter, can draw no conclusion from the con-ectness of the man-
ner of thinking an object to the reality of the object itself. Yet
among modern, nay recent, philosophers, two
The true relations of -^ j ^ • i ^ i • i
- . , , ^ . opposite doctrines have sprung up, which, on
Logic overlooKed m ^^ _ ^ r- o r' j
two ways:— 1. Logic Opposite sides, have overlooked the true rela-
erroneousiy held to tions of Logic. "One party of philosophers
be the positive stand- defining truth in general, — the absolute har-
ard of truth. ® . .
mony of our thoughts and cognitions, — divide
truth into a formal or logical, and into a material or metaphysical,
according as that harmony is in consonance witli
The division of truth ^^le laws of formal thought, or, over and above,
into logical and meta- • i i i c ^ ^ i t i mi
physical,- criticized. ^ith the laws of real knowledge.^ The criterion
of formal truth they place in the principles of
Contradiction and of Sufficient Reason, enouncing that what is non-
contradictory and consequent is formally true. This criterion, which
is positive and immediate of formal truth (inasmuch as what is
non-contradictory and consequent can always be thought as possi-
ble), they style a negative and mediate criterion of material truth :
as what is self-contradiotory and logically inconsequent is in reality
impossible ; at the same time, what is not self-contradictory and not
logically inconsequent, is not, however, to be regarded as having an
actual existence. But here the foundation is treacherous ; the no-
tion of truth is false. When we speak of truth, we are not satisfied
with knowing that a thought harmonizes with a certain system of
thoughts and cognitions ; but, over and above, we require to be
, assured that what we think is real, and is as we
Truth, — what. ,.,. . • j^ -,
think it to be. Are we satisfied on this point,
we then regard our thoughts as true ; whereas if we are not satis-
fied of this, we deem them false, how well soever they may quad-
1 See Kant, Logik, Einleitung, vii. ; Krug, Logik, $ 22; Fries, Logik, { 42. — Ed.
Lkct. vl logic. 77
rate with any theoiy or system. It is not, therefore, in any absolute
harmony of mere thought that truth consists, but solely in the cor-
respondence of our thoughts with their objects. The distinction of
formal and material truth is thus not only unsound in itself, but
opposed to the notion of truth universally held, and embodied in all
languages. But if this distinction be inept, the title of Logic, as a
positive standard of truth, must be denied ; it can only be a nega-
tive criterion, being conversant with thoughts and not with things,
with the possibility and not with the actuality of existence."^
The preceding inaccuracy is, however, of little moment compared
with the heresy of another class of philosophers,
2. The Absolutists to whose observations on this point I can, how-
proceed on a subver- ^ ^^j allude. Some of you may, perhaps,
sion of the logical „ ' _.r. ,.,,.. •; •" ^ / '
i^^g iind a dimculty in beheving the statement, that
there is a considerable party of philosophers,
illustrious for the highest speculative talent, and whose systems, if
not at present, were, a few years ago, the most celebrated, if not the
most universally accredited in Europe, who establish their meta-
physical theories on the subversion of all logical Iruth.^ I refer to
those philosophers who hold that man is capable of more than a
relative notion of existence, — that he is competent to a knowledge
of absolute or infinite being (for these terms they use convertibly),
in an identity of knowledge and existence, of himself and the
Divinity. This doctrine, which I shall not now attempt to make
you understand, is developed in very various schemes ; that is, the
different philosophers attempt, by very diiferent and contradictory
methods, to arrive at the same end ; all these systems, however,
agree in this, — they are all at variance with the four logical laws.
Some, indeed, are established on the express denial of the validity
of these laws; and othei-s, without daring overtly to reject their au-
thority, are still built in violation of their precept. In fact, if con-
tradiction remain a criterion of falsehood, if Logic and the lawG of
thought be not viewed as an illusion, the philosophy of the absolute,
in all its forms, admits of the most direct and easy refutation. But
on this matter I only now touch, in order that you may not be
ignorant that there are philosophers, and philosophers of the high-
est name, who, in pursuit of the phantom of absolute knowledge,
are content to repudiate relative knowledge, logic, and the laws of
thought. This hallucination is, however, upon the wane, and as
each of these theorists contradicts his brother, Logic and Common
Sense will at length refute them all.
Before leaving the consideration of this subject, it is necessary to
1 Eeser, Lo^k, p. 6&-6. — Ed. 2 See above, p. 64, note 4. — Ed.
78 LOGIC. Lect. VI.
notice a mistake of Dr. Reid, which it is not more remarkable
that he should have committed, than that others
Mistake of Reid in j^^^^^ ^^^^ ^^^^^^^ ^^ f^,j^^, ^^^^ applaud it, as the
regard to Conception. ' '
correction of a general error. In the fourth
^ssay on the Intellectual Powers., and in the third chapter, entitled
Mistakes concerning Conceptions^ there is the following passage,
which at once exhibits not only his own opinion, but the universality
of the doctrine to which it is opposed :
" There remains," he says, " anotlier mistake concerning concep-
tion, which deserves to be noticed. It is, that
Reid quoted. , /. . • • ». i •
our conception oi thmgs is a test oi their pos-
sibility, so that, what we can distinctly conceive, we may conclude
to be possible ; and of what is impossible, we can have no con-
ception.
" This opinion has been held by philosophere for more than a hun-
dred years, without contradiction or dissent, as far as I know ; and,
if it be an error, it may be of some use to inquire into its origin, and
the causes that it has been so generally received as a maxim whose
truth could not be brought into doubt."
I may here observe that this limitation of the prevalence of the
opinion in question to a very modern period is altogether incorrect ;
it was equally prevalent in ancient times, and as many passages could
easily be quoted from the Greek logicians alone as Dr. Reid has
quoted from the philosophers of the century prior to himself. Dr.
Reid goes on :
" One of the fruitless questions agitated among the scholastic
philosophers in the dark ages was. What is the criterion of truth?
As if men could have any other way to distinguish truth from error,
but by the right use of that power of judgment which God has
given them.
"Descartes endeavored to put an end to this controveray, by
making it a fundamental principle in his system, that whatever we
clearly and distinctly perceive, is true.
" To understand this principle of Descartes, it must be observed
that he gave the name of perception to every power of the human
understanding; and in explaining this very maxim, he tells us
that sense, imagination, and pure intellection, are only different
modes of perceiving, and so the maxim was understood by all his
followers.
"The learned Dr. Cudworth seems also to have adopted this prin-
ciple. 'The criterion of true knowledge,' he says, 'is only to be
looked for in our knowledge and conceptions themselves: for the
1 Collected Works, p. 376-8. —Ed.
Lect. VI. LOGIC. 79
entity of all theoretfcal truth is nothing else but clear intelligibility,
and whatever is clearly conceived is an entity and a truth ; but that
which is false, Divine power itself cannot make it to be clearly and
distinctly understood. A falsehood can never be clearly conceived
or apprehended to be true.' — {Eternal and immutable Morality, p.
172, etc.)
" This Cartesian maxim seems to me to have led the way to that
now under consideration, which seems to have been adopted as the
proper correction of the former. When the authority of Descartes
declined, men began to see that we may clearly and distinctly con-
ceive what is not true, but thought that our conception, though not
in all cases a test of truth, might be a test of possibility.
" This indeed seems to be a necessary consequence of the received
doctrine of ideas ; it being evident that there can be no distinct im-
age, either in the mind or anywhere else, of that which is impos-
sible. The ambiguity of the word conceive, which we observed.
Essay i. chap, i., and the common phraseology of saying, we cannot
conceive such a thing, when we would signify that we think it im-
possible, might likewise contribute to the reception of this doctrine.
" But whatever was the origin of this opinion, it seems to prevail
universally, and to be received as a maxim.
" ' The bare having an idea of the proposition proves the thing not
to be impossible ; for of an impossible proposition there can be no
idea.' — Dr. Samuel Clarke.
"'Of that which neither does nor can exist we can have no idea.'
— Lord Bolingbroke.
"'The measure of impossibility to us is inconceivableness, thatof
which we have no idea, but that reflecting upon it, it appears to be
nothing, we pronounce to be impossible.' — Abernethy.
"'In every idea is implied the possibility of the existence of its
object, nothing being clearer than that there can be no idea of an
impossibility, or conception of what cannot exist.' — Dr. Price.
" ' Impossibile est cujus nullam notionem formare possumus; pos
sibile e contra, cui aliqua respondet notio.' — Wolfii Ontolog.
" ' It is an established maxim in metaphysics, that whatever the
mind conceives, includes the idea of possible existence, or in other
woi-ds, that nothing we imagine is absolutely impossible.' — D.
Hume.
" It were easy to muster up many other respectable authorities for
this maxim, and I have never found one that called it in question.
"If the maxim be true in the extent which the famous Wolfius
has given it in the passage above quoted, we shall have a short road
to the determination of every question about the possibility or im-
80 LOGIC. Lect. VL
possibility of things. We need only look into our own breast, and
that, like the Urim and Thuramim, will give an infallible answer. If
we can conceive the thing, it is possible ; if not, it is impossible.
And surely every man may know whether he can conceive what is
affirmed, or not.
"Other philosophers have been satisfied with one half of the
maxim of Wolfius. They say, that whatever we can conceive is
possible ; but they do not say, that whatever we cannot conceive is
impossible."
On this I may remai'k, that Dr. Reid's criticism of Wolf must be
admitted in so far as that philosopher maintains our inability to con-
ceive a thing as possible, to be the rule on which we are entitled to
pronounce it impossible. But Dr. Reid now advances a doctrine
which I cannot but regard as radically erroneous.
"I cannot help thinking even this to be a mistake which philoso-
phers have been unwarily led into, from the causes before mentioned.
My reasons are these :
" 1, Whatever is said to be possible or impossible is expressed by
a proposition. Now, what is it to conceive a proposition ? I think
it is no more than to understand distinctly its meaning. I know no
more that can be meant by simple apprehension, or conception,
when applied to a proposition. The axiom, therefore, amounts to
this : — Every proposition, of which you understand the meaning
distinctly, is possible. I am persuaded that I understand as distinctly
the meaning of this proposition, Any two sides of a triangle are to-
gether equal to the third, as of this. Any two sides of a triangle are
together greater than the third; yet the first of these is impossible."
Now this is a singular misunderstanding of the sense in which it
has been always held by philosophei-s, that what
Criticized.
is contradictory is conceived as inconceivable and
impossible.^ No philosopher, I make bold to say, ever dreamt of
denying that we can distinctly understand the meaning of the propo-
sition, the terms of which we recognize to be contradictory, and, as
contradictory, to annihilate each other. When we enourtce the pro-
position, A is not A, we clearly comprehend the separate meaning
of the terms A and not A, and also the import of the assertion of
their identity. But this very understanding consists in the con-
sciousness that the two terms are contradictories, and that as such
it is impossible to unite them in a mental judgment, though they
stand united in a verbal proposition. If we attempt this, the two
mutually exclusive terms not only cannot be thought as one, but in
fad annihilate each other ; and thus the result, in place of a positive
1 See the Author's notes, Rtid^s Worka^ p. 877. — Ed.
Lkct. VI LOGIC. 81
judgraent, is a negation of thouglit. So fai* Dr. Reid is wrong. But
lie is not guilty of the absurdity attributed to him by Dr. Gleig; he
does not say, as by that writer he is made to say, that " any two
sides of a triangle may be conceived to be equal to the third, as dis-
tinctly as any two sides of a triangle may be conceived to be greater
tlian the third." ^ These are not Dr. Reid's words, and nothing he
says warrants the attribution of such expressions to him, in the sense
in which they are attributed. He is made to hold, not merely that
we can understand two terms as contradictory, but that we are able
to combine them in the unity of thought. After the passage ah'eady
quoted, Reid goes on to illustrate, in various points of view, the
supposed error of the philosophers ; but as all he says on this
head originates in the misconception already shown of the opin-
ion he controverts, it is needless to take <^ny further notice of his
arguments.
We have thus considered the conditions of Logic, in so far as cer-
tain laM's or principles are prescribed ; we have
Postulates of Logic. , ., . -,.^. . „
now to consider its conditions, m so tar as cer-
tain postulates are demanded. Of these there are more than one :
but one alone it is here requisite to signalize ; for although it be ne-
cessarily supposed in the science, strange to say, it has, by logical
writers, not only been always .passed over in silence, but frequently
and inconsistently violated. This postulate I comprise in the follow-
ing paragraph :
% XVIII. The only postulate of Logic which requires an ar-
ticulate enouncement is the demand, that
Par. x^i- The logi- jjefore dealing with a ludgment or reasoning
oal postulate. o j o o
expressed in language, the import of its
terms should be fully understood ; in other words. Logic postu-
lates to be allowed to state explicitly in language all that is
implicitly contained in the thought.
This postulate cannot be refused. In point of fact, as I have said,.
Logic has always proceeded on it, in overtly ex—
This postulate can- • n iu x £• ^i, ^ i
^ ^ ^ pressing all the steps ot the mental process m-
not be refused. . . . .
reasoning, — all the propositions of a syllogism;:
whereas, in common parlance, one at least of these steps or proposi-
tions is usually left unexpressed. This postulate, as we shall have
occasion to observe in the sequel, though a fundamental condition
of Logic, has not been consistently acted op by logicians in their
development of the science ; and from this omission have arisen
1 Art. "Metaphysics," Sncyclopadi/z Eritannica, Ttbedit., p. 620. — Ed
11
82 LOGIC. Lect. VI.
much confusion and deficiency and error in our present system of
Logic. The illustration of this postulate will appropriately find its
place on occasion of its applications. I now articulately state it,
because it immediately follows in order the general axioms of the
science ; and, at present, I only beg that you will bear it in mind. I
may, however, before leaving the subject, observe
This postulate im- (what has already, I believe, been mentioned),
plied in the doctrine ^j^^^ Aristotlc States of syllogistic— and, of course,
of Syllogism, accord- ,. t • •
ing to Aristotle. "^^ Statement applies to Logic m general — that
the doctrine of syllogism deals, not with the ex-
teraal expression of reasoning, in ordinary language, but with the
internal reasoning of the mind itself.^ But of this again, and more
fully, in the proper places.
In like manner, we might here, as is done in Mathematics, pre-
mise certain definitions ; but these it will be more convenient to
state as they occur in the progress of our development. I there-
fore pass on to the Second Section of the Doctrine of Elements,
which is occupied with the Products of Thought ; in other words,
with the processes regulated by the previous conditions.
1 AnaL PNt., i. 10. — IEd. t
LECTURE VII.
STOICHEIQLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT.
I. ENNOEMATIC — OF CONCEPTS OR NOTIONS.
A. OF CONCEPTS IN GENERAL.
I CONCLUDED, in my last lecture, all that I think it necessary to
say in regard to the Fundamental Laws of Thought, or the neces-
sary conditions of the thinkable. The discussion, I am aware, must
have been found somewhat dry, and even abstruse ; not that there
is the smallest difficulty in regard to the apprehension of the laws
themselves, for these are all self-evident propositions, but because,
though it is necessary in a systematic view of Logic to commence
with the elementary principles of thought, it is impossible, in speak-
ing of these and their application, not to employ expressions of the
most abstract generality, and even not to suppose a certain acquaint-
ance with words and things, which, however, only find their expla-
nation in the subsequent development of the science.
Having considered, therefore, the four Laws of Thought, with the
one Postulate of Logic, which constituted the
The products of First Section of the Doctrine of Logical Ele-
Thought, Concepts, j^^^j^^ j j^^^^. proceed to the Second — that
Judgments and Rea- , . , . x • i t-» t
sonings. which 18 conversant about Logical Froducts.
These products, though identical in kind, are of
three different degrees ; for while Concepts, Judgments, and Rea-
sonings, are all equally the products of the same Faculty of Compar-
ison, they still fall into three classes, as the act.
These are all pro- and, consequently, the result of the act, is of a
ducts of Comparison, ^atcr or a less simplicity. These three degrees
and all modifications ° . i .^ • r i,
of judgment. ^^^ ^^^ i" fi'ct, strictly, only modifications of the
second, as both concepts and reasonings may hv
reduced to judgments; for the act of judging, that is, the act of
affirming or denying one thing of another in thought, is that in
which the Understanding or Faculty of Comparison is essentially
84 LOGIC. Lect. VH,
expressed. By anticipation : — A concept is a judgment; for, on
the one hand, it is nothing but the result of a foregone judgment, or
series of judgments, fixed and recorded in a word — a sign ; and it
is only amplified by the annexation of a new attribute, through a
continuance of the same process. On the other hand, as a concept
is thus the synthesis or complexion, and the record, I may add, of
one or more prior acts of judgment, it can, it is evident, be analyzed
into these again ; every concept is, in fact, a judgment or a fascicu-
lus of judgments — these judgments only not explicitly developed
in thought, and not formally expressed in terms.
Again, a reasoning is a judgment ; for a reason is only the affirma-
tion of the connection of two things with a third, and, through that
third, with each other. It is thus only the same function of thought,
which is at work in Conception, Judgment, and Reasoning ; arid
these express no real, no essential, distinction of operation, but
denote only the different relations in which we may regard the indi-
visible act of thought. Thus, the consideration of concepts cannot
be effected out of all relation to, and without even some anticipation
of, the doctrine of judgments. This being premised, I now proceed
to the consideration of the Products of Thought, viewed in the
three relations of the three degi-ees, of Concepts, Judgments, and
Reasonings.^
Under the Second Section of Stoicheiology, Concepts or Notions
form the first chapter.
Now, in treating of Concepts, the order I shall follow is this : — I
shall, in the first place, treat of them in general ;
I. Of Concepte or j^ ^^^ second, treat of them in special. Under
Notions, — order of , ^ i i i mi i -j j
discussion. ^"^ former, or general head, will be considered,
1°, What they are ; 2°, How they are produced.
Under the latter, or special head, they will be considered under
their various relations. And here, I may obser^'e, that as you
obtain no information from Dr. Whately in re-
Whateiy* omission ^^^ ^^ ^j^^, primary laws of thought, — these
ofthedoctrineof Con- » . .
ggptg laws being in fact apparently unknown to every
British logician, old or new, — so you will find
but little or no aid from his Elements towards an understanding of
the doctrine of concepts. His omission, in this respect, cannot be ex-
cused by his error in regard to the object-matter of Logic ; that object,
you will recollect, being on his view, or rather one of his views, not
thought in general, or the products of the comparative faculty in
1 [Hume, Treatise of Human Nature, Bk. i. prehension is impossible without judgment
part iii. { 7- Jac. Thomasius, Physica, p. 295] Compare also Kmg, LogUc, f 23, Anm. ii. p. TO
[c. zljx. ( 112, where be holds that simple ap- — Ed.]
ILect. VIL LOGIC. ^5
their three degrees, but reasoning or argumentation alone ; for even
on the hypothesis that Logic is thus limited, still, as the doctrine of
reasoning can only be scientifically evolved out of the doctrine of
concepts, the consideration of the latter forms the indispensable
condition of a satisfactory treatment of the former. But not only is
Whately's doctrine of concepts, or, in his language, of " the process
of simple apprehension," meagre and imperfect, it is even necessary
to forewarn you that it leads to confusion and error. There is a
iundamental distinction of what is called the Extension and the
Comprehension of notions — a distinction which,
Whateiy abusively in fact, as you will find, forms the very cardinal
employs the terms Ex- -^^ ^^ ^j^-^j^ ^^^ ^j^^j^ ^y^ ^^ ^-^ ^^^.^^
tension and Compre- i.^ ,.,.,.. . .....
hensioii as convertible. ^^^ "^^t Only IS thlS distmction not explained. It IS
not even articulately stated ; nay, the very words
which logicians have employed for the expression of this contrast,
are absolutely used as synonymous and convertible. Instead, there-
fore, of referring you for information in regard to our present object
of consideration, to Dr. Whateiy, I am sorry to be compelled to
caution you against putting confidence in his guidance. But to re-
turn. The following I dictate as the title of the first head to be
considered :
A. Of Concepts or ^ Qf Concepts or Notions in General : What
Notions in general. i o ' »
What they are. ^rC they ?
In answering this question, let us, first, consider the meaning of
the expressions ; and, secondly, the nature of the thing expressed,
^ XIX. Concept or notion (^evvoia, iwoiQixxi, vorjfia, cTrtvoia,'
conceptio, notio), are terms employed as
Far. XIX. Concepts. Convertible, but, while they denote the same
term^*^*^"^* ^ ^ thi"g» they denote it in a diflferent point of
view. Conception, the act of which concept
is the result, expresses the act of comprehending or grasping up
1 In Greek, the terms ?»'j'oia {fvvor)TiK6s), Uus, Lexicon Pkilosophicum, v. 'N6Tifia, p. 890,
iwoviJia (4vvorifmTiK6s), inivoia [iirivoririK- and p. 80, [i-. Alad^fiara. Cf. p. 310, v. Con-
is), viy,^, to say nothing of iniV07t,u>. {iir^- ''Ptus; p. 633, t,. Intentio.-E.T>^ Onvo^f^ara.
/ V „ ...... see Aristotle, De /n<erpr..c 1. and Waitz, Coni-
v<n)u.a,rtKOS), are all more or less objection- „„_ , • ■ ^ i.. I^ t ■
^' , ' , , . , J - mejUanus, p. 327. In Aristotle, De Anirna.
able, as all more or less ambiguously used for , ... „ ,,, ^ ,., „ ,_, . „/. _,_
^. ',. , ^ . 4..K i,» • . /• 1- lii. CO. 6, 7 7, 8 8, 9, etc., vo^^aTa are
the object or product of thought, in an act of , , . , \ .
.,. . ,, „ . clearly equivalent to concept.'in our meaning.
Conception, or, as it has been usually called , .» >« / i
l.v the logicians, Simple Apprehension. See ^^ "' '^ '^ ^ , „ >
!• immidas. Epitome Logica[c. V. UtpVEvLv- roirois, irepj & ovk tan rh iptvSos iv ols Sf
<'a^. p 31. ed. 1605. — Ed ]; Eugenics, Logica %ai. rh ^fvios koH rh iX-r^fS, aivbevis -ti
lAivi/c)), c. ii. p. 170, Leipsic, 1766. — Ed ] ^5,j votiiiATtcv &<nr(p %v 6vtcdv. k. t. ^. —
Slephanus, Thesaurus, v. tiovs; Hiicker, CZavis Ed j
P/iii. Arist., V. No^j/taro, p. 227 et seq. ; Micrae-
t'5 LOGIC. lect. vn.
into unity the various qualities by which an object is character-
ized; notion {notio)^ again, signifies either the act of appre-
hending, signalizing, that is, the remarking or taking note of,
the various notes, marks, or characters of an object, which its
qualities afford ; or the result of that act.
In Latin, the word cancipere^ in its many various applications,
always expresses, as the etymology would indi-
iiinstfated, — em- cate, the process of embracing or comprehending
*^ / ^ the many into the one, as could be shown by an
«« mente conctpere, and . .
animi conceptiu. articulatc analysis of the phrases in which the
term occurs. It was, accordingly, under this
general signification, that this word and its derivatives were ana-
logically applied to the ojjeration of mind. Animo vel mente con-
cipere, as used by Cicero, Pliny, Seneca, and other Roman writers,
means to comprehend or understand, that is, to embrace a multitude
of different objects by their common qualities into one act of
thought ; and animi conceptus was, in like manner, applied by the
ancient writers to denote this operation, or its result. The employ-
ment of concipere, conceptus, and conceptio, as
Oi c<mcip.re, concep. ^e^jj^j^j^^i ^crms. In the Philosophy of Mind,
Iks, and conceptio, with- ^ _ •* "^
out adjunct. without the explanatory adjunct, was of a later
introduction — was, indeed, only possible after
they had been long familiarly used in a psychological relation. But
when so introduced, they continued to be employed by philosophere
in general in their proper signification as convertible with thought or
comprehension, and as opposed to the mere apprehension of Sense
or Imagination. Not, indeed, that examples enough may not be
adduced of their abusive application to our immediate cognitions of
individual objects, long before Mr. Stewart formally applied the
term conception to a certain accidental form of representation — to
the simple reproduction or repetition of :'.n act of perception in
imagination.' In using the temis conception and concept in the
sense which I have explained, I therefore employ them not only in
strict conformity to their grammatical meaning, but to the meaning
which they have generally obtained among philosophers.
The term notion, like conception, expresses both an act and its
product. I shall, however, as has commonly
The term notion,- -^^^^ AowQ, usc it Only in this latter relation.
Iiow employed by the _,, . i i ti .1
^^jjjjjj. Ihis word has, like conception, been sometimes
abusively applied to denote not only our knowl-
edge of things by their common characters, but, likewise, to include
1 See Lectuns on Melaphysica, p. 462 uq. — Ed.
I
Lect. Vn. LOGIC. 87
the mere presentations of Sense and representations of Phantasy.
This abusive employment has, however, not been so frequent in
reference to this terra as to the term conception ; but it must be
acknowledged, that nothing can be imagined more vague and vacil-
lating than the meaning attached to notion in the writings of all
British philosophere, without exception. So much for the expres-
sions concept and notion. I now go on to that which they express.
^ XX.^ — In our Consciousness — apprehension — of an indi-
vidual object, there may be distinguished
Par. XX. Concepts. ^hc two following coguitious : — 1°, The
— (b) Nature of the , o o
tiling. immediate and irrespective knowledge we
have of the individual object, as a comple-
ment of certain qualities or characters, considered simply as
belonging to itself. 2°, The mediate and relative knowledge
we have of this object, as comprising qualities or characters
common to it with other objects.
The former of these cognitions is that contained in the Pre-
sentations of Sense, external and internal, and Representations
of Imagination. They are only of the individual or singular.
The latter is that contained in the Concepts of the Under-
standing, and is a knowledge of the common, general, or uni-
versal.
The conceiving an object is, therefore, its recognition medi-
ately through a concept; and a Concept is the cognition or
idea of thq general character or characters, point or points, in
which a plurality of objects coincide.
This requires some illustration, and it will be best afforded by
considering the history of our knowledge. Our
Concepts,— their na. mental activity is not first exerted in an appre-
ture illustrated by ref- , . /. , i . „
erence to the history heusiou of the general, common properties of
of our knowledge. things. On the Contrary, objccts are originally
Objects are originally presented to US in coufused and imperfect percep-
presented in confused , • mi_ t ^-i^ "iti o
, . ^ ^ tions. Ihe rude materials lurnished by bense,
and imperfect percep- ^ . .
tions. retained in Memory, reproduced by Reminis-
cence, and represented in Imagination, the Un-
derstanding elaborates into a higher knowledge, simply by means
of Comparison and Abstraction. The primary act of Comparison
is exerted upon the individual objects of Perception and Imagination
1 On this and three following paragraphs tt seq. — [Meditationes de Cognitione Teritatst
apply Leibnitz's distinction of Intuitive and et Ideis. — Ed.]
Symbolical Knowledge, see Opera II. i. p. 14
88 LOGIC. Lect. VIL
alone. In the multitude and complexity of these objects, certain
attributes are found to produce similar, others
Offices of Compan- ^^ produce dissimilar, impressions. The obser-
8on and Abstraction . ^ , , r- i • a .•
or attention vation of this lact determmes a reflective con-
sideration of their properties. Objects are in-
tentionally compared together for the purpose of discovering their
similarities and differences. When things are found to agree or to
disagree in certain respects, the consciousness is, by an act of voli-
tion, concentrated upon the objects which thus partially agree, and,
in them, upon those qualities in or through which they agree ; and
by tliis concentration — whicl* constitutes the act called Attention
— Avhat is eflfected ? On the objects and qualities, thus attentively
considered, a strong light is shed; but precisely in proportion as
these are illuminated in consciousness, the others, to which we do
not attend, are thrown into obscurity.
The result of Attention, by concentrating the mind upon certain
qualities, is thus to withdraw or abstract it from
Prescision, Attention, j^ll elsc. In technical language, we are said to
and Abstraction are • y ^^ t l • i i • i
, ^. - prescind the phaenomena whicli we exclusively
correlative names for .
the same process. Consider. To prescind^ to attend^ and to abstract,
are merely different but correlative names for
the same process ; and the first two are nearly convertible. When
we are said to prescind a quality, we are merely supposed to attend
to that quality exclusively ; and when we abstract, we are properly
said to abstract from, that is, to throw otlier attributes out of ac-
count. I may observe that the term abstraction is very often abu-
sively employed. By Abstraction we are frequently said to attend
exclusively to certain phaenomena, — those, to wit, which we ab-
stract; whereas, the term abstraction is properly applied to the
qualities which we abstract from ; and by abstracting from some, we
are enabled to consider others more attentively. Attention and
Abstraction arc only the same process viewed in diffeient relations.
They are, as it were, the positive and negative poles of the same
act.'
By Comparison, the points of resemblance among things being
thus discovered, and by Attention constituted into exclusive ob-
jects ; by the same act they are also reduced in consciousness from
multitude to unity. What is meant by this will be apparent from
the following considerations.
1 See Lecturts on Metapkysies, p. 474 , and Logik, i&;Krixf(, LogiJc,i i9. —E,T>. [Schulze
Baobmann, Logilc, i 44 Compare Kant, Logile, i 28; Drobisch, LogHe,i li, p. 11 ette<ii
Lect. VII. LOGIC. 89
We are conscious to ourselves that we can repeat our acts of con«
sciousness — that we can think the same thought
Thereduction of Ob- ^^^^ ^^^ ^^^^ rpj^j^ ^^. ^j^-^ thought, is al-
jects from multitude o ^
to unity, — explained ways in reaUty the same, though manifested at
and illustrated. different times : for no one can imagine that in
Thought is one and ^he repetition of one and the same thought, he
the fame, while its , i v^ ^ ^i, i_i j? i •
contents are identical. ^^^ a plurahty of thoughts ; for he IS conscious
that it is one and the same thought which is
repeated, so long as its contents remain identical.
Now, this relation of absolute similarity which subsists between
the repetitions of the same thought, is found to
Objects are to us the hold between our representations of the resem-
same when we are un- •,,. ,.,. /« i- - m t.- x i
,, , .. ,. .^ bung qualities 01 obiects, Iwo obiects have sim-
able to distmguish ... .
their cognitions. i^^r qualities only as these qualities afford a
similar presentation in sense or a similar repre-
sentation in imagination, and qualities are to us completely similar,
when we are unable to distinguish their cognitions. But what we
cannot distinguish, is, to us, the same ; therefore, objects which de-
termine undistinguishable impressions upon us, are perceived and
represented in the same mental modification, and are subjectively
to us precisely as if they were objectively identical.
But the consciousness of identity is not merely the result of the
indiscernible similarity of total objects, it is
The consciousness equally the result of the similarity of any of
of identity is equally their parts — partial characters. For by ab-
the result of the simi- j. i.' -u i* x* xi, tx- • i
, . „ , , stracting observation from the quahties, points,
lanty of any cf the , , ° _ , ....
partial characters of i^ which objects differ, and limiting it to those
objects. in which they agree, we are able to consider
them as identical in certain respects, however
diverse they may appear to be in othei-s, which, for the moment,
we throw out of view. For example : let B, G, and T> represent a
series of individual objects, which all agree in possessing the resem-
bling attributes of y y y, and severally differ in ench respectively
possessing the non-resembling attributes i, o, u. Now, in so far as
we exclusively attend to the resembling qualities, we, in the first
place, obscure or remove out of view their non-resembling charac-
ters i, o, u, while we remain exclusively conscious of their resem-
bling qualities y y y. But, in the second place, the qualities
expressed \yj yy y determine in us cognitive energies which we are
unable to distinguish, and which we, therefore, consider as the
same. We therefore view the three similar qualities in the three
different objects as also identical ; we consider the y in this, the y
in that, and the y in the third object, as one ; and in so far as the
12
90 LOGIC. Lect. VIL
three objects participate in this oneness or identity, we regard them
as also the same. In other words, we classify B, C, and D, under y ;
y is the genus ; B, C, and D are its individuals or species, severally
distinguished from each other by the non-resembling properties, t,
o, u. Now, it is the points of similarity thus discovered and iden-
tified in the unity of consciousness, which constitute Concepts or
Notions.
It is evident that the same process of Comparison and Abstrac-
tion may be again performed on the concepts thus fonned. They
are, in like manner, compared togethei-, and
Generalization. . . ' r & »
their points of resemblance noted, exclusively
considered, and reduced to one in the synthesis of thought. This
process is called Generalization; that is, the process of evolving the
general or one, out of the individual and mani-
concepts or notions fold. Notions and concepts are also sometimes
super uousy sy designated by the style of general notions —
general conceptions. This is supei-fluous ; for, in
propriety of speech, notions and concepts are, in their very nature,
general ; while the other cognitive modifications to which they are
opposed, — perceptions and imaginations, — have, in like manner,
their essence in their individuality.
By the way, you may have noticed that I never use the term
idea. The reason of my non-employment of
jrffa,— reason why that word i§ this: There is no possible diversity
not regularly employ- ^f meaning in which that term has not been
ed, and sense in which ^ . it i /» -r
it is occasionally used, usurped ; and It would only confuse you, were I
by the Author. to attempt to enumerate and explain them. I
may, however, occasionally not eschew the
word ; but if you ever hear it from me, I beg you to observe, that I
apply it, in a loose and general signification, to comprehend the
presentations of Sense, the representations of Phantasy, and the
concepts or notions of the Understanding. We are in want of a
generic term to express these ; and the word representation {repre-
sentatio), which, since the time of Leibnitz, has been commonly
used by the philosophers of the Continent, I have restricted to
denote, what it only can in propriety express, the immediate object
or product of Imagination. We are, likewise, in want of a general
term to express what is common to the presentations of Perception,
and the representations of Phantasy, that is, their individuality and
immediacy. The Germans express this by the term Anschauungy
which can only be translated by intuition (as it is in Latin by Ger-
mans), which literally means a looking at. Tliis expression has,
however, been preoccupied in English to denote the apprehension
Lect. Vn. LOGIC. 91
we have of self-evident truths, and its application in a different sig-
nification, vrould therefore be, to a certain extent, liable to am-
biguity. I shall, therefore, continue, for the present at least, to
struggle on without such a common term, though the necessity thus
imposed of always opposing presentation and representation to con-
cept is both tedious and perplexing.
^ XXI. A concept or notion thus involves — 1°. The repre-
sentation of a part only of the various attri-
Generai Characters ^^^^^ ^^ characters of which an individual
of Concepts.
Par. XXI. (a) A Con- objcct is the sum ; and, consequently, affords
only a one-sided and inadequate knowledge
of the things which are thought under it.
cept affords only in-
adequate Icnowledge,
This is too simple to require any commentary. It is evident that
when we think Socrates by any of the concepts.
Explication. .,. ^ttt y ■ ^ .
— At/ienian, Cireefc, Jburopean, man, oipea, ani-
mal, being, — we throw out of view the far greater number of
characters of which Socrates is the complement, and those, like-
wise, which more proximately determine or constitute his individu-
ality. It is, likewise, evident, that in proportion as we think him
by a more general concept, we shall represent him by a smaller
bundle of attributes, and, consequently, represent him in a more
partial and one-sided manner. Thus, if we think him as Athe-
nian, we shall think him by a greater number of qualities than if we
think him by Greek ; and, in like manner, our representation will
be less and less adequate, as we think him by every higher concept
in the series, — European, man, biped, animal, being.
^ XXII. 2°, A concept or notion, as the result of a compari-
son, necessarily expresses a relation. It is.
Par. XXII. (b) A Con. , „ "^ . ii • • i^ i • •
cept affords no abso- therefore, not cognizable m itself; that is, it
lute object of knowi- affords uo absolute or irrespective object of
knowledge, but can only be realized in con-
sciousness by applying it, as a term of relation, to one or more
of the objects, which agree in the point or points of resem-
blance which it expresses.
In this paragraph (if I may allude to what you may not all be
aware of) is contained a key to the whole mystery of Generalization
and General Terms ; for the whole disputes between the Concep-
tualists and Nominalists (to say nothing of the Realists) have only
arisen from concepts having been regarded as affording an irre-
92 LOGIC. ' Lect. VII.
spective and independent object of thought.* This illusion ha.s
arisen from a very simple circumstance. ObjeelB
Tiiis paragraph con- compared together are found to possess certain
tains a key to the attributes, which, as producing indisceraible
mystery of General!- Tn ^- • \ i i ^ i • -i
zation and General modincations m US, are to us absolutely similai*.
Ternis. They are, therefore, considered the same. The
relation of similarity is thus converted into
identity, and the real plurality of resembling qualities in nature is
factitiously reduced to a unity of thought ; and this unity obtains a
name in which its relativity, not being expressed, is still further
removed from observation.
But the moment we attempt to represent to ourselves any of
these concepts, any of these abstract generalities,
Wherein consists j^g absolute objects, by thcmselves, and out of
^ ° ' ^ relation to any concrete or individual realities,
their relative nature at once reappears ; for we
find it altogether impossible to represent any of the qualities ex-
pressed by a concept, except as attached to some individual and
determinate object ; and their whole generality consists in this, —
that though we must realize them in thought under some singular
of the class, we may do it under any. Thus, for example, we can-
not actually represent the bundle of attributes contained in the
concept man, as an absolute object, by itself^ and apart from all that
reduces it from a general cognition to an individual representation.
We cannot figure in imagination any object adequate to the general
notion or term man; for the man to be here imagined must be
neither tall nor short, neither fat nor lean, neither black nor whit**,
neither man nor woman, neither young nor old, but all and yet
none of these at once. The relativity of our concepts is thus shown
in the contradiction and absurdity of the opposite hypothesis.
1 For a ftill accooot of this dispute, see Leeturea on Mttapkysies, p. 477 «( to. — Bd.
LECTURE VIII.
STOICHEIOLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT
L— ENNOEMATIC.
A. OF CONCEPTS IN GENERAL; B. IN SPECIAL— I. THEIR
OBJECTIVE RELATION — QUANTITY.
In our last Lecture, we began the Second Section of Stoicheiol-
ogy, — the consideration of the Products of Thought. The product
of thought may be considered as Concepts, as
Recapitulation, with Judgments, and as Reasonings ; these, however,
further explanation , . , ,^ , „-,.^
andiiiustration. ^'"^ "°^ ^^ "® Viewed as the results of different
faculties, far less as processes independent of
each other, for they are all only the product of the same energy in
different degrees, or rather in simpler or more complex applications
to its objects.
In treating of Concepts?, which form the subject of the First
Chapter of this Second Section, I stated that I should first consider
them in general, and then consider them in special ; and, in my Inst
Lecture, I had nearly concluded all that I deem it requisite under
the former head to state, in regard to their peculiar character, their
origin, and their general accidents. I, first of all, explained the
meaning of the two terms, concept and notion, — words convertible
with each other, but still severally denoting a different aspect of
the simple operation, which they equally express. Notion being
relative to and expressing the apprehension, — the remarking, —
the taking note of, the resembling attributes in objects; concept,
the grasping up or synthesis of these in the unity of thought.
Having shown what was properly expressed by the terms notion
and concept, or conception, I went on to a more articulate explana-
tion of that which they were employed to denote. And here I
•Tgain stated what a Concept or Notion is in itself, and in contrnst
to a Presentation of Perception, or Representation of Phantasy.
Our knowledge through either of the latter, is a direct, immediate.
94 LOGIC. Lect. Vm
irrespective, determinate, individual, and adequate cognition ; that
is, a singular or individual object is known in itself, by itself, through
all its attributes, and without reference to aught but itself. A con-
cept, on the contrary, is an indirect, mediate, relative, indeterminate,
and partial cognition of any one of a number of objects, but not an
actual representation either of them all, or of the whole attributes
of any one object.
Though it be not strictly within the province of Logic to explain
the origin and formation of our notions, the logician assuming, as
data, the laws and products of thought, jxs the mathematician as-
sumes, as data, extension and number and the axioms by which
their relation is determined, both leaving to the metaphysician
the inquiry into their grounds ; — this notwithstanding, I deemed
it not improper to give you a very brief statement of the mode and
circumstances in which our concepts are elaborated out of the pre-
sentations and representations of the subsidiary faculties. Different
objects are complements partly of similar, partly of different, attri-
butes. Similar qualities are those which stand in similar relation
to our organs and faculties, and where the similarity is complete,
the effects which they determine in us are, by us, indiscernible. To
us they are, therefore, virtually the same, and the same we, accord-
ingly, consider them to be, though in different objects ; precisely as
we consider the thought of the same object to be itself the same,
when repeated at intervals — at different times — in consciousness.
This, by way of preface, being understood, I showed that, in the
formation of a concept or notion, the process may be analyzed into
four momenta. In the first place, we must have a plurality of ob-
jects presented or represented by the subsidiary faculties. These
faculties must furnish the rude material for elaboration. In the sec-
ond place, thg objects thus supplied are, by an act of the Under-
standing, compared together, and their several qualities judged to
be similar or dissimilar. In the third place, an act of volition,
called Attention, concentrates consciousness on the qualities thus
recognized as similar; and that concentration, by attention on them,
involves an abstraction of consciousness from those which have
been recognized and thrown aside as dissimilar ; for the power of
consciousness is limited, and it is clear or vivid precisely in propor-
tion to the simplicity or oneness of its object. Attention and Ab-
straction are the two poles of the same act of thought ; they are
like the opposite scales in a balance — the one must go up aa the
other goes down. In the fourth place, the qualities, which by com-
parison are judged similar, and by attention are constituted into an
exclusive object of thought, — these are already, by this process,
Lect. viii. logic. 95
idcntifieil in consciousness; for tliey are only judged similar, inas-
much as they produce in us indiscernible effects. Their synthesis in
consciousness may, however, for precision's sake, he stated as a
fourth step in the jirocess ; Ijut it must be remembered, tliat at least
the three latter steps arc not, in reality, distinct and independent
acts, but are oldy so distinguished and stated, in order to enable
us to com])rehend and speak about the indivisible 0])eration, in the
different aspects in which we may consider it. In the same way,
you ai-e not to su])pose that tlie mental sentence which must be ana-
lyzed in order to be expressed in laugua^e, lias as manv parts in
consciousness, as it has words, or clauses, in s]>eech ; for it f )rms, in
reality, one organic and indivisible whole. To rc])eat an illustra-
tion 1 have already given, — the ]»arts of an act of thought stand in
the same relation to each other as the parts of a triangle, — a figure
Avhicli we cannot resolve into any simpler figure, but whose sides
and angles we may consi<ler apart, and, therefore, as parts; though
these are, in reality, inseparable, being tlie necessary conditions of
each other. lUit this by the way.
The qualities of ditlcrcnt individual things, thus identified in
tliought, and constituting concepts, under which, as classes, these
individual things themselves are ranged; — these primary concepts
may themselves be subjected to the same process, by which they
were elaborated from the concrete realities given in Perception and
Imagination. We may, again, compare different concepts together,
again find in the jilurality of attributes which they comprehend,
some like, some unlike; we may again attend only to the similar,
and again identify these in the synthesis of consciousness; and this
process of evolving concepts out of concepts we may go on per-
forming, until the generalization is arrested in that ultimate or pri-
mary concejjt, the basis itself of all attributes, — the conce])t of
Being or Existence.
Having thus endeavored to give you a general view of what con-
cepts are, and by what process they are formed, I stated, by way of
corollary, some of their general characteristics. The first of these I
mentioned is their partiality or inadequacy; that is, they compre-
hend only a larger or smaller portion of the whole attributes belong-
ing to the things classified or contained under them.
The second is their relativity. Formed by comparison, they ex-
press only a relation. They cannot, therefore,
e a ui y o .on- ^^^ held up as an absolute object to consciousness,
cepts. ^ •'
— they cannot be represented, as universals, in
imagination. They can only be thought of in relation to some one
of the individual objects they classify, and when viewed in relation
96 LOGIC. Lect. Vm
to it, they can be represented in imagination ; but then, as so actu-
ally represented, they no longer constitute general attributions, they
fall back into more special determinations of the individual object in
which they are represented. Thus it is, that the generality or uni-
versality of concepts is potential, not actual. They are only gener-
als, inasmuch as they may be applied to any of the various objects
they contain ; but while they cannot be actually elicited into con-
sciousness, except in application to some one or other of these, so,
they cannot be so applied without losing, joro tanto, their universal-
ity. Take, for example, the concept horse. In so far as by horse
we merely think of the word, that is, of the combination formed by
the letters A, o, r, s, e, — this is not a concept at all, as it is a mere
representation of certain individual objects. This I only state and
eliminate, in order that no possible ambiguity should be allowed to
lurk. By horse, then, meaning not merely a representation of the
word, but a concept relative to certain objects classed under it; —
the concept horse, I say, cannot, if it remain a concept, that is, a
universal attribution, be represented in imagination ; but, except it
be represented in imagination, it cannot be applied to any object;
and, except it be so applied, it cannot be real-
Concepts have a po- j^ed in thought at all. You may try to escape
tential, not an actual, , , /> i ti t 17-
univereaiitv. ^'^^ horns oi the dilemma, but you cannot. You
cannot realize in thought an absolute or irrespec-
tive concept, corresponding in univei-sality to the application of the
word ; for the supposition of this involves numerous contradictions.
An existent horse is not a relation, but an extended object possessed
of a determinate figure, color, size, etc.; horse, in general, cannot,
therefore, be represented, except by an image of something extended,
and of a determinate figure, color, size, etc. Here now emerges the
contradiction. If, on the one hand, you do not represent something
extended and of a determinate figure, color, and size, you have no
representation of any horee. There is, therefore, on this alternative,
nothing which can be called the actual concept or image of a hoi-se
at all. If, on the other hand, you do represent something extended
and of a determinate figure, color, and size, then you have, indeed,
the image of an individual liorse, but not a universal concept coad-
equate with horse in general. For how is it possible to have an act-
ual representation of a figure, which is not a determinate figure ?
but if of a determinate figure, it must be that of some one of the
many different figures under which horses appear ; but then, if it be
only of one of these, it cannot be the general concept of the othei*s,
which it does not represent. In like manner, how is it possible to
have the actual representation of a thing colored, which is not the
Lect. yiii. logic. 9.7
representation of a determinate color, that i.s, either white, or black,
or gray, or brown, etc. ? but if it be any one of these, it can only
represent a horse of this or that particular color, and cannot be the
o-eneral concept of horses of every color. The same result is given
by the other attributes ; and what I originally stated is thus mani-
fest, — that concepts have only a potential, not an actual, universal-
ity; that is, they are only universal, inasmuch as they may be applied
to any of a certain class of objects, but as actually applied, they are
no longer general attributions, but only special attributes.
But it does not from this follow that concepts are mere words,
and that there is nothing general in thought it-
But concepts are not, ^^jf. rpj^j^ j^ ^^^ j^^^^^ j^^j^ j^ ^^^-^^ ,
therefore, mere words. . j j j
philosopher ; for no philosopher has ever denied
that we are capable of apprehending relations, and in particular
the relation of similarity and difference ; so that the whole contro-
versy between the conceptualist and nominalist originates in the
ambiguous employment of the same terms to express the represen-
tations of Imagination and the notions or concepts of the under-
standing. This is significantly shown by the absolute non-existence
of the dispute among the philosophers of the most metaphysical,
country in Europe. In Germany, the question of nominalism and'
conceptualism has not been agitated, and why? Simply because
the German language supplies terms by which concepts (or notions
of thought proper) have been contradistinguished from the presen-
tations and representations of the subsidiary faculties.' But this
is not a subject on which I ought at present to have touched, as it
is, in truth, foreign to the domain of Logic; and I have only been
led now to recur to it at all, in consequence of some difficulties ex-
pressed to me by members of the class. All that I wish you now
to understand is — that concepts, as the result of comparison, that
is, of the apprehension and affirmation of a relation, are necessarily, ,
in their nature relative, and, consequently, not capable of represen-
tation as absolute attiibutes. I shall terminate the consideration ^
of concepts in general by the following paragraph, in which is-
stated, besides their inadequacy and i-elativity, their dependence on .
language :
% XXIII. The concept thus formed by an abstraction of
the resembling from the non-resembling qualities of objects,,
would again fall back into the confusion and infinitude from.'
1 See the Author's note, Reicfs Works, p. 412; and Lectures on Metaphysics, p. 477 et seq.
— Ed.
13
98 LOGIC. Lect. vin.
which it has been called out, were it not rendered permanent
for consciousness, by being fixed and ratified
Par. xxirr. Con- in a verbal sign. Considered in general,
cepts,-(o) xheir de- thought and language are reciprocally de-
pendenoe on Lan- ^ o o i j
guage. pendent; each bears all the imperfections
and perfections of the other; but without
language there could be no knowledge realized of the essential
properties of things, and of the connection of their accidental
states.
This also is not a subject of which the consideration properly
belongs to Logic, but a few words may not be
The relation of Lan- inexpedient to make you aware, in general, of the
guage to Thought, and intimate connections of thought and its expres-
the influence which it , -, ^ .-, r t • n t-ii
exerts on our mental ^^^n, and of the powerful influence which Ian-
operations. guag6 exerts upon our mental operations. Man,
in fact, only obtains the use of his faculties in
obtaining the use of speech ; for language is the indispensable mean
of the development of his natural powere, whether intellectual or
moral.
For Perception, indeed, for the mere consciousness of the similar-
ities and dissimilarities in the objects perceived,
Language unneces- f^^. ^Y\e apprehension of the causal connection
Orations ^^ Certain things, and for the application of this
knowledge to the attainment of certain ends,
no language is necessary ; and it is only the exaggeration of a truth
into an error, when philosophers maintain that language is the indis-
pensable condition of even the simpler energies of knowledge.
Language is the attribution of signs to our cognitions of things.
But as a cognition must have been already there, before it could
receive a sign ; consequently, that knowledge which is denoted by
the formation and application of a word, must have preceded the
symbol which denotes it. Speech is thus not the mother, but the
godmother, of knowledge. But though, in general, we must hold
that language, as the product and correlative of thought, must be
viewed as posterior to the act of thinking itself; on the other hand,
it must be admitted, that we could never have risen above the very
lowest degrees in the scale of thought, without the aid of signs.
A sign is- necessary, to give stability to our intellectual progress, —
to establish each step in our advance as a new starting-point for
our advance to another beyond.
A country may be overrun by an armed host, but it is only
conquered by the establishment of fortresses. Words are th«»
i:ect. VIIL logic. 99
fortresses of thought. They enable us to realize our dominion over
what we have already overrun in thought; to
• Mental operations to make every intellectual conquest the basis of
w ic anguage is in- operations for others still beyond. Or another
dispensable, and its ^ ^ ^ •'
relation to these illustration : You have all heard of the process
of tunnelling, of tunnelling through a sand-bank.
In this operation it is impossible to succeed, unless every foot, nay
almost every inch in our progress, be secured by an arch of masonry,
before we attempt the excavation of another. Now, language is to
the mind precisely what the arch is to the tunnel. The power of
thinking and the power of excavation are not dependent on the
word in the one case, on the mason-work in the other ; but without
these subsidiaries, neither process could be cairied on beyond its rud-
imentary commencement. Though, therefore, we allow that every
movement forward in language must be determined by an antece-
dent movement forward in thought ; still, unless thought be accom-
panied at each point of its evolution, by a corresponding evolution
of language, its further development is arrested. Thus it is, that
the higher exertions of the higher faculty of Understanding, — the
classification of the objects presented and represented by the subsi-
diary powers in the formation of a hierarchy of notions, the connec-
tion of these notions into judgments, the inference of one judgment
from anothqjTi and, in general, all our consciousness of the relations
of the universal to the particular, consequently all science strictly
so denominated, and every inductive knowledge of the past and
future from the laws of nature : — not only these, but all ascent
from the sphere of sense to the sphere of moral and religious intelli-
gence, are, as experience proves, if not altogether impossible without
a language, at least possible to a very low degree.
Admitting even that the mind is capable of certain elementary
concepts without the fixation and signature of language, still these
are but sparks which would twinkle only to expire; and it I'equires
words to give them prominence, and, by enabling us to collect and
elaborate them into new concepts, to raise out of what would oth-
erwise be only scattered and transitory scintillations a vivid and
enduring light.
I here terminate the General and proceed to the Special consid-
eration of Concepts — that is, to view them in
B Of Concepts or ^j^^j^. gg^g^^j Relations. Now, in a logical point
notions in special. , . i i
of view, there are, it seems to me, only three
possible relations in which concepts can be considered ; for the only
relations they hold are to their objects, to their subject, or to each
LOGIC. Lect. vm,
other. In relation to their objects,-^ they are considered as inclu-
sive of a greater or smaller number of attributes, that is, as applica-
ble to a greater or smaller number of objects; this is technically
styled their Quantity. In relation to their subject, that is, to the
mind itself, they are considered as standing in a higher or a lower
degree of consciousness, — they are more or less clear, more or less
distinct ; this, in like manner, is called their Quality. In relation'
to each other, they are considered as the same or different, coordi-
nated or subordinated to each other ; this is their Relation, strictly
so called.* Under these three heads I now, therefore, proceed to
treat them ; and, first, of their Quantity.
^ XXIV. As a concept, or notion^ is a thought in which an
indefinite plurality of characters is bound
Par. XXrV. Quan. . . „ . , ,.
tity of coneeptB of up luto a uuity oi consciousucss, and appli-
two kinds. Intensive cable to an indefinite plurality of objects, a
and Extensive. • i i> • i
concept IS, thereiore, necessarily a quantity,
and a quantity varying in amount according to the greater
or smaller numbers of characters of which it is the complement,
and the greater or smaller number of things of which it may
be said. This quantity is thus of two kinds ; as it is either an
Intensive or an Extensive. The Internal or Intensive Quantity
of a concept is determined by the greater or smoker number
of constituent character contained in it. The External or Ex-
tensive Quantity of a concept is determined by the greater or
smaller number of classified concepts or realities contained un-
der it. The former (the Intensive Quantity) is called by some
latter Greek logicians the depth ()8a5os), by the Latin logical
writers the comprehension {comprehension quantitas eompre-
hensionis, complexits, or quantitas comjilexus). The latter (the
Extensive Quantity) is called by the same latter Greek Logi-
cians, the breadth (irXaTo?) ; by Aristotle, -q irepto)^ to TrcpUxfty,
TO ir€p«;^€o--Sai ; - by the logical writers of the western or Latin
world, the extension or circuit \exte7isio, quantitas extensionis^
hi.
* On their relation to their origin as direct 9P, By relation to each other they hare m-
or indirect, see Esser, [System der Lo^k, ( 49, lation strictly so called,
p. 96. — Ed.] 40. By relation to their subject they have
Mem. — N. B. Notions may be thus better clearness and distinctness.
divided {?): (This last had bettor be relef^ated to Method-
10 ». 1 •• A AX. , At. X. AX. olojrv.) — Memoranda.
l". By relation to themselves thev have the „ „ . ., 1 . <..
^ ^,. - . . iSec Lectures on Metnphystes, p. 4t An. Arii«-
qtMntity of comprehension. . ,. ^ . i. . .,
totle does not use -rtptoxv as a substantive,
2^, By relation to their objects they have though the verb, both active and passive, ia
the quantity of extension. These two thus employed in this siffnification, «./;. .4ihi/. IV<^
quantity in general. i. 27; Rlut. iii. 6. — Ed. (
t*OT. vm. tOGie. 101
ambitus, quantitus ambitus) ; and likewise the cfo/iuxi;. or
sphere of a notion {regie, sphcBra)}
The Internal Quantity of a notion, its Intension or Comprehen-
sion, is made up of those different attributes of
<ieneral Explication. , . . , • , . , ,
which the concept is the conceived sum ; that
is, the various characters connected by the concept itself into a
single whole in thought. The External Quantity of a notion or its
extension is, on the other hand, made up of the number of objects
which are thought mediately through a concept. For example, the
attributes ratiotial, sensible, moral, etc., go to constitute the inten-
sion or internal quantity of the concept m,a7i; whereas the attributes
European, American, philosopher, tailor, etc., go to make up a con-
cept of this or that individual man. These two quantities are not
convertible. On the contrary, they are in the inverse ratio of each
other; the greater the depth or comprehension of a notion the less
its breadth or extension, and vice versa. You will observe, like-
wise, a distinction which has been taken by the best logicians.
Both quantities are said to contain,' but the quantity of extension
is said to contain under it; the quantity of comprehension is said to
contain in it.
By the intension, comprehension, or depth of a notion, we think
the most qualities of the fewest objects ; whereas by the extension
or breadth of a concept, we think the fewest qualities of the most
objects. In other words, by the former, we say the most of the
least ; by the latter, the least of the most.
Again ; you will observe the two following distinctions : the first,
— the exposition of the comprehension of a notion is called its
Definition (a simple notion cannot, therefore, be defined) ; the
second, * — the exposition of the Extension of a notion is called its
Division (;m individual notion cannot be divided).
1 (Cf. Porpltyrii, Isagoge, cc. i. ii. viii. ; Caje- hic extensive. Porphyrius autem loquebatur
tan. In Porphyrii Praidicabilia, CC. i. ii. [p. 37 ett hic de extensiva collectioue, ideo dixit, genu*
1579 ; prefixed to his Commentary on the Cat- esse magis collectivum." Quoted by Stahl,
fgories. first published in 1496. " Ad hoc Regulce Pliilosophicct, tit. xii., reg. 5, p. 381.
breviter dicitur, quod esse magis collectivum Cf. reg. 6, ed. London, 1658. — Ed.] [Port-
multorum potest intelligi dupliciter: uno Royal Logic, P. i. c. 6, p. 74, ed. 1718. Boe-
modo intensive, et sic species magis est collec- thius, Introductio ad Syllogismos, Opera, p. 562:
tiva, quia magis unit adunata; alio modo ex- Tn Topica Cieeronis Cornmentarii, lib. i., Opern,
tensive, et sic genus est magis collectivum, p. 765, ed. Basilar, 1570. Reuschius, Systema
nuia multo plura sub sua adunatione cadunt, Logicum, pp. 11, 92; Baumgarten, Acmo^'-i
<ni»m sub speciei ambitu. Unde species et Lo?»>a, §§ 56. 57, ed. Hala Magdeburgse. 177$
pcnus Fo habent sicut duo duces, quorum alter Rrug, Losik, § 26; Schulze, Logil: § 30; Esther,
laVctcxercitumparvumsedvaldeunanimem, Logik, ? 34 et seg. ; Eugenics, p. 194 et .<■«/.
•.liter cxercitum magnum, sed diversarum [Ao7(k:^, c. iv., Hepl 'Ewoiwi' Bct&OJ/y t«
Eactionum. 1 lie enim magis colligit intensive, KolUxiiTovs Ed.]
102 LOGIC. Lect. vm
What follows is in further illustration of the paragraph. Notions
or concepts stand in a necessary relation to cer-
Speciai iiinstration ^^-^ objects, thought through them ; for without
of Paragraph. — A /. ' f ,. f i -i
concept is a quantity. Something to thmk of, there could exist no
thought, no notion, no concept. But in so far
as we think an object through a concept, we think it as part of, or
as contained under, that concept : and in so far as we think a con-
cept of its object or objects, we think it as a unity containing,
actually or potentially, in it a plurality of attributions. Out of the
relation of a concept to its object it necessarily results, that a con-
cept is a quantum or quantity ; for that which contains one or more
units by which it may be measured, is a quantity.
But the quantity of a concept is of two, and two opposite, kinds.
Considered internally, that is, as a unity whicl^
This quantity of two ^^^ generally does, contain in it a plurality
Jcinds: — !. Intensive. „ ., '
of parts or component attributes, a concept has
a certain quantity, which may be called its internal or intensive
quantity. This is generally called its comprehensiony sometimes its
depths PaJ^o^y and its quantitas complexus. Here, the parts, that is,
the several attributes or characters, which go to constitute the total
concept, are said to be contained in it. For example, the concept
man is composed of two constituent parts or attributes, that is, of
two partial concepts, — rational and animal; for the characters
rational and animal are only an analytical expression of the syn-
thetic unity of the concept man. But each of these partial con-
cepts, which together make up the comprehension of the total
concept mariy are themselves wholes, made up in like manner of
parts. To take only the concept animal ; — this comprehends in
it, as parts, living and sensitive and organized^ for a living and sen-
tient organism may be considered as an analytical development of
the constituents of the synthetic unity animal. But each of these,
ag.iin, is a concept,, comprehending and made up of parts; and these
parts, again, are relative wholes, divisible into other constituent
concepts; nor need we stop in our. analysis till we reach attributes
which, as simple, stand as a primary or ultimate element, into which
the series can be resolved. Now, you will observe, that as the
parts of the parts are parts of the whole, the concept man^ as imme-
diately comprehending the concepts rational and animal, medi-
ately comprehends their parts, and the parts of their parts, to tho
end of the evolution. Thus, we can s.ny, not only that man is an
animal, but that he is a living being, a sentient being, etc. The'
logical axiom, Nota notes est nota ret ipaittSy or, as otherwise ex-
I
Lect. Vm. LOGIC. 103
pressed, Prcedicatum prcedicati est prcedicatum suhjecti,^ — is only
a special enunciation of the general principle, that the part of a part
is a part of the whole. You will, hereafter, see that the Compre-
hension of notions affords one of the two great branches of reason-
ing, which, though marvellously overlooked by logicians, is at least
of equal importance with that which they have exclusively devel-
oped, and which is founded on the other kind of quantity exhibited
by concepts, and to which I now proceed.
But a concept may also be considered externally, that is, as a unity
which contains under it a plurality of classifyins:
2 Extensive. . .
attributes or subordinate concepts, and, in this
respect, it has another quantity which may be called its external or ea-
tensive quantity. This is commonly called its extension- sometimes
its sphere or domain, sphcera, regio, quantitas ambitus/ and, by the
Greek logicians, its breadth or latitude, ttAcitos.^ Here the parts which
the total concept contains, are said to be contained under it, because,
holding the relation to it of the particular to the general, they are sub-
ordinated or ranged under it. For example, the concepts man, horse,
dog, etc., are contained under the more general concept animal, —
the concepts triangle, square, circle, rhombus, rhomboid, etc., are con-
tained under the more general cowce^t figure; inasmuch as the sub-
ordinate concepts can each or any be thought through the higher or
more general. But as each of these subordinate concepts is itself a
whole or general, which contains under it parts or more particular
concepts, it follows, again, on the axiom or self-evident truth that a
part of a part is a part of the whole, — an axiom which, you will here-
after see, constitutes the one principle of all Deductive reasoning, —
it follows, on this axiom, that whatever is contained under the par-
tial or more particular concept, is contained under the total or more
general concept. Thus, for example, triangle is contained under
figure; all, therefore, that is contained under triangle, as rectangled
triangle, equilateral triangle, etc., will, likewise, be contained under
figure, by which we may, accordingly, think and describe them.
Such, in general, is what is meant by the two quantities of con-
cepts— their Comprehension and Extension.
But these quantities are not only different, they
Intensive and Ex- Qxe opposed, and SO opposed, that though each
tensive quantities are .■■ ., ^, ,. ,. „ .,
opposed toeach other. supposes the Other as the condition of Its own
existence, still, however, within the limits of con-
junct, of correlative existence, they stand in an inverse ratio to each
1 A traiiRlotion of Aristotle's first nntipre- xarriyopov/xevov Keyerat irdvra Kal Karh rod
dicameiital rule, Ca/eg-., iii. l."Off« (cara toC vTroKeiixivo'j f>ri^-fi(reTai. — Ed.
'■i Seu above, p 100, r.ote 2, p. 101, no'o 1.— V.v.
Wi LOGIC. Lkct. vnL
other, — the maximum of the one being the minimum of the other.
On this I give you the following paragraph :
% XXV. A notion is intensively great in proportion to the
greater number, and intensively small in
Par. XXV. Law reg- proportiou to the Smaller number, of deter-
nlating the mutual re- .. ^^-i, •!.•. t
lationB of Extension mmatious OF attributes contained m it. Is
and Comprehension the Comprehension of a concept a mini-
mum, that is, is the concept one in which a
plurality of attributes can no longer be distinguished, it is
called simi^le ; whereas, inasmuch as its attributes still admit of
discrimination, it is called complex or compound}
A notion is extensively great in proportion to the greater num-
ber, and extensively small in proportiou to the smaller number,
of determinations or attributes it contains under it. When
the Extension of a concept becomes a minimum, that is, when it
contains no other notions under it, it is called an individual.^
These two quantities stand always in an inverse ratio to each
other : For the greater the Comprehension of a concept, the less
is its Extension ; and the greater its Extension, the less its Com-
prehension.^
To illustrate this : When I take out of a concept, that is, ab-
stract from one or more of its attributes, I dimin-
lUustration. • i • i • m, , /> i
ish Its comprehension. 1 hus, when from the con-
cept man, equivalent to rational animal, I abstract from the attribute
or determination rational, I lessen its internal quantity. But by this
diminution of its comprehension I give it a wider extension ; for what
remains is the concept animal, and the concept animal embraces
under it a far greater number of objects than the concept man.
Before, however, proceeding further in illustrating the foregoing
paragraph, it may be proper to give you also the following :
% XXVI. Of the logical processes by
Par. XXVI. prooess- which thcsc countcr quantities of concepts
«B by which the Com- , ^ , '
prehension and Ex. are amplified, — the one which amplifies the
tension of Notions Comprehension is called Detertnination,
sre amplified and * . n t >-.
resolved. and somctimes called Concretion, the other
which amplifies the Extension is called Ab-
straction or Generalization. Dejinitian and Division are sever-
1 Knig, Logik^ \ 28. —Ed. o&rck ciSw*' irtpioxf) Tck 8J cWr/ rHv ytt-mr
a Krug, iWd , § 29. - Ed. xXwi/efC" raTj o.Vei'aj 5ia*opa?j. "f-ri oCr,
3 Krug, Loffiyt, f 27. — Ed.; [Schulze, Loff'*, ,,./,- - * v
♦ 88. Cf. Porphyry, Isagog,, c. viii. H 9, 10.] ^^ '^"^ T*'^"' '^ y*y^'->r<TOV' offrc t*
Lect. Vm. LOGIC. 105
ally the resolntion of the Compi*ehension and of the Extension
of notions, into their parts. A Simple notion cannot be defined ;
an Individual notion cannot be divided.^
The reason of this opposition of the two quantities is manifest in
a moment, from the consideration of their sev-
iiiustration o t e ^^^ natures. The comprehension of a concept is
two foregoing para- . '■ ^
rapijg. nothmg more than a sum or complement of the
distinguishing characters, attributes, of which
the concept is made np ; and the extension of a concept is nothing
more than the sum or complement of the objects
Comprehension and themselves, whose resembling characters were
Extension are op- abstracted to Constitute the concept. Now, it
ratio to each other. ^® evident, that the more distinctive characters
the concept contains, the more minutely it will
distinguish and determine, and that if it contain a plenum of dis-
tinctive characters, it must contain the distinctive — the deter-
mining— characters of some individual object. How do the two
quantities now stand ? In regard to the comprehension or depth, it
is evident, that it is here at its maximum, the concept being a com-
plement of the whole attributes of an individual object, which, by
these attributes, it thinks and discriminates from every other. On
the contrary, the extension or breadth of the concept is here at its
minimum ; for, as the extension is great in proportion to the num-
ber of objects to which the concept can be applied, and as the object
is here only an individual one, it is evident that it could not be less,
without ceasing to be at all. Again, to reverse the process : throw-
ing out of the comprehension of the concept, that is, abstracting
from those attributes, which belonging exclusively to, exclusively dis-
tinguish, the individual, — we at once diminish the comprehension,
by reducing the sum of its attributes, and amplify the extension of
the concept, by bringing within its sphere all the objects, which the
characteristics, now thrown out of the comprehension, had pre-
viously excluded from the extension. Continuing the process, by
abstraction we throw out of the sum of qualities constituting the
comprehension, other discriminating attributes, and forthAvith the
extension is pi'oportionally amplified, by the entrance into its sphere
of all those objects which had previously been debarred by the
determining characteristics last discarded. Thus proceeding, and
at each step ejecting from the comprehension those characters
1 ISynonyms of Abstraction: — 1, Analysis — 1, Analysis (of Extension); 2, Synthesis; 3,
(of Comprehension); 2, Syntliesis; 3, Gener- Specification; 4, Kestrictionj 5, Individua-
ification; 4, Induction; 5, Ampliflcation. tion.]
Synonyms of Determination or Concretion :
u
106 LOGIC. Lkct. vni.
which are found the proximate impediments to the amplification of
the extension of the concept, we at each step diminish the former
quantity precisely as we increase the latter; till, at last, we arrive
at that concept which is the necessary constituent of every other, —
at that concept which all comprehension and all extension must
equally contain, but in which comprehension is at its minimum,
extension at its maximum, — I mean the concept of Being or Exist-
ence}
We have thus seen, that the maximum of comprehension and
the minimum of extension are found in the con-
Definition and Di- ^g^ Qf ^^ individual, — that the maximum of
vision, — are the pro- '■ , t , • • « i •
cesses by which Com- extension and the minimum of comprehension
prehension and Ex- are fouud in the concept of the absolutely sim-
tension of Concepts p]g^ ^^^ Jg^ J^ ^j^g COllCept of existence. NoW,
are resolved. , . , ^ . ...
comprehension and extension, as quantities, are
wholes ; for wholes are only the complement of all their parts, and
as wholes are only by us clearly comprehended as we distinctly
comprehend their parts, it follows : — 1°, That comprehension and
extension may each be analyzed into its parts ; and, 2", That this
analysis will afford the mean by which each of these quantities can
be clearly and distinctly understood. But as the two quantities are
of an opposite nature, it is manifest, that the two processes of analy-
sis will, likewise, be opposed. The analysis of the intensive or
comprehensive quantity of concepts, that is, their depth, is accom-
plished by Definition ; that of their extensive quantity, or breadth,
by division. On Definition and Division I at present touch, not to
consider them in themselves or on their own account, that is, as the
methods of clear and of distinct thinking, for this will form the mat-
ter of a special discussion in the Second Part of Logic or Method-
ology, but simply in so far as it is requisite to speak of them in
illustration of the general nature of our concepts.
The expository or -explanatory analysis of a concept, considered
as an intensive whole or quantum, if properly
Definition Illustrated. „ ,., ,. ,. . rrj
eftected, is done by its resolution into two con-
cepts of which it is proximately compounded, that is, into the higher
concept under which it immediately stands, and into the concept
which affords the character by which it is distinguished from
the other coordinate concepts under that higher concept. This is
its definition ; that is, in logical language, its exposition by an
analysis into its Genus and Differential Quality; — the genus b6ing
the higher concept, under which it stands ; the differential qujility
I ThI.*, like other logical relations, may be typified by a sensible figure. (See below, p. IW.
— Ed.]
Lect. VUL LOGIC. 107
the lower concept, by which it is distinguished from the other con-
cepts subordinate to the genus, and on a level or coordinate with
itself, and which, in logical language, are called /Species. For ex-
ample : if we attempt an expository or explanatory analysis of the
concept man^ considered an an intensive quantity or complexus of
attributes, we analyze it into animal^ this being the higher concept
or genus, under which it stands ; and into rational, the attribute of
reason being the characteristic or differential quality by which man
is distinguished from the other concepts or species which stand
coordinated with itself under the genus animal, — that is, irrational
animal or brute.
Here you will observe, that though the analysis be of the compre-
hension, yet it is regulated by the extension ; the extension regulat-
ing the order in which the comprehension is resolved into its parts.
The expository analysis of a concept, an extensive whole or
quantum, is directly opposed to the preceding,
to which it is correlative. It takes the higher
concept, and, if conducted aright, resolves it into its proximately
lower concepts, by adding attributes which afford their distinguish-
ing characters or differences. This is division : — Thus, for exam-
ple, taking the highest concept, that of ens or existence, by adding
to it the differential concepts per se or substantial, and no7i per se
or accidental, we have substantial existence or existence per se,
equivalent to substance, and accidental existence or existence nan per
se, equivalent to accident. We may then divide substance by sim-
ple and not-simple, equivalent to compound, and again simple by
material and non-material, equivalent to immaterial, equivalent to
spiritual; — and matter or material substance by organized and not-
organized, equivalent to brute matter. Organized matter we may
divide by sentient or animal, and non-sentient or vegetable. Ani-
mal we may divide by rational and irrational, and soon, till we
reach a concept which, as that of an individual object, is, in fact,
not a general concept, but only in propriety a singular representa-
tion.
Thus, it is manifest, that, as Definition is the analysis of a complex
concept into its component parts or attributes,
The Indefinable and •/. ^ v • i x-l ^ • -^ '^ a. • • -^
J .. . ... II a concept be simple, that is, if it contain m it
only a single attribute, it must be indefinable ;
and again, that as Division is the analyses of a higher or more gen-
eral concept into others lower and less general, if a concept.be an
individual, that is, only a bundle of individual qualities, it is indi-
visible, is, in fact, not a proper or abstract concept at all, but only a
concrete representation of Imagination.
108
LaGIC.
Lbot. YSL
Diagram represent-
ing Extension and
Comprehension of
Concepts.
B.
D.
'vi.
1.
V.
2.
iv.
3.
iii.
4.
iL
5.
i.
6.
The following Diagram^ represents Breadth
and Depth, with the relations of Affirmation and
legation to these quantities.
Schemes of the Two QuAifTiTiES.
Line of BreadtTu
Aff. Neg.
A
A
A
A
A
A \A
<
E
E
E
E
E
\E
I'
I
I
I
I
\I
^
V
O
O
O
|0:
U
U
1^^
s
Y
1^
1 ' "
zlz z
...
k
Ground of Reality.
Explanation.
In the preceding Table there are represented : — by A, A, etc.,
the highest genus or widest attribute ; by Y, the
lowest species or narrowest attribute; whilst
the other four horizontal series of vowels typify the subaltern gen-
era and species, or the intermediate attributes. The vowels are
reserved exclusively for classes, or common qualities; whereas the
consonants z, /, z" (and which, to render the contrast more obtru-
sive, are not capitals) represent individuals, or singulars. Every
higher class or more common attribute is supposed (in conformity
with logical precision) to be dichotomized, — to be divided into two
by a lower class or attribute, and its contradictory or negative.
This contradictory, of which only the commencement appears, is
marked by an italic vowel, preceded by a perpendicular line ( | )
signifying not or now, and analogous to the minus ( — ) of the math-
ematicians. This being understood, the table at once exhibits the
reed identity and rational differences of Breadth and Depth, which,
though denominated quantities, are, in reality, one and the same
quantity, viewed in counter relations and from opposite ends. Noth-
ing is the one, which is not pro tanto, the other.
In Sreadtk : the supreme genus (A, A, etc.) is, as it appears, abso-
1 The Diagram and relative text to end of Leotore ire extracted by the Editors ttom the
Author's Ditcussionaf p. 699—701. — Ed.
Lect. Vm. LOGIC« 109
lately the greatest whole ; an individual (z) absolutely the smallest
part ; whereas the intermediate classes are each of them a relative
part or species, by reference to the class and classes above it; a
relative whole or genus, by reference to the class or classes below
it. In Depth : the individual is absolutely the greatest whole, the
highest genus is absolutely the smallest part; whilst every relatively
lower class or species, is relatively a greater whole than the class,
classes, or genera, above it. The two quantities are thus, as the
diagram represents, precisely the inverse of each other. The greater
the Breadth, the less the Depth ; the greater the Depth, the less the
Breadth ; and each, within itself, affording the correlative differences
of whole and part, each, therefore, in opposite respects, contains and
is contained. But, for distinction's sake, it is here convenient to
employ a difference, not altogether arbitrary, of expression. We
should say: — "containing and contained under^ for Breadth; —
"containing and contained iVi," for Depth. This distinction, which
has been taken by some modern logicians, though unknown to many
of them, was not observed by Aristotle. We find him (to say noth-
ing of other ancient logicians) using the expression Iv oAw dvai or
vwdpxeiv, for either whole. Though different in the order of thought,
{ratione), the two quantities are identical in the nature of things,
{re). Each supposes the other ; and Breadth is not more to be dis-
tinguished from Depth, than the relations of the sides, from the rela-
tions of the angles, of a triangle. In effect it is precisely the same
reasoning, whether we argue in Depth, — "z' is {i.e. as subject,
contains in it the inherent attribute) some Y ; all Y is some U ; all
U is some O ; all O is some I ; all I is some E ; all E is some A ; —
therefore, z' is some A : " or whether we argue in Breadth, — " Some
A is {i. e. as class, contains under it the subject part) all E ; some
E is all I ; some I is all O ; some O is all U ; some U is all Y ; some
Y is z' ; therefore, some A is z'." The two reasonings, internally
identical, are externally the converse of each other; the premise
and term, which in Breadth is major, in Depth is minor. In syllo-
gisms also, where the contrast of the two quantities is abolished,
there, with difference of figure, the differences of major and minor
premise and term fall likewise. In truth, however, common lan-
guage in its enouncement of propositions, is hei-e perhaps more cor-
rect and philosophical than the technical language of logic itself.
For as it is only an equation — only an affirmation of identity or
its negation^ which is, in either quantity, proposed ; therefore the
substantive verb {is, is not), used in both cases, speaks more accu-
rately, than the expression, contained (or not contained), in of the
one, contained (or not contained)^ under of the other. In fact, the
no LOGIC. Lkct. VIIL
two qtcantities and the two quantifications have by logicians been
neglected together.
This Table (the principle of which becomes more palpably dem-
onstrative when the parts of the table are turaed into the parts of a
circular machine ^ ) exhibits all the mutual relations of the counter
quantities. — 1°, It represents the classes, as a series of resemblances
thought as one (by a repetition of the same letter in the same
series), but as really distinct (by separating lines). Thus, A is only
A, not A, A, A, etc ; some Animal is not some Animal ; one class
of Animals is not all, every, or any other; this Animal is not that;
Socrates is not Plato ; z is not z'. On the other hand, E is E A;
and YisYUOIEA; every lower and higher letter in the series
coalescing uninterruptedly into a series of reciprocal subjects and
predicates, as shown by the absence of all discriminating lines.
Thus Socrates (z') is Athenian (Y), Greek (U), European (O), Man
(I), Mammal (E), Animal (A). Of course the series must be in
grammatical and logical harmony. We must not collate notions
abstract and notions concrete. — 2°, The Table shows the inverse
correlation of the two quantities in respect of amount. For exam-
ple : A (t, e. A, A, etc.), the highest genus represented as having six
times the Breadth of Y ; whilst Y (t. e. Y — A), the lowest species,
has six times the Depth of A. — 3", The table manifests all the
classes, as in themselves unreal, subjective, ideal ; for these are
merely fictions or artifices of the mind, for the convenience of think-
ing. Univereals only exist in nature, as they cease to be universal
in thought; that is, they are reduced from general and abstract
attributes to individual and concrete qualities. A — ^Y are only truly
objective as distributed through z, z', z", etc. ; and in that case they
are not universals. As Boethius expresses it : " Omne quod est, eo
quod est, singulare est." — 4°, The opposition of class to class,
through contradictory attributes, is distinguished by lines different
from those marking the separation of one part of the same class
from another. Thus, Animal, or Sentiently-organized (A), is con-
trasted with Not-animal, or Not-sentiently-organized ( | A)^ by lines
thicker than those which merely discriminate one animal (A) from
another (A).'
1 A machine of this kind vras constrncted t See Airther in Diuusnoiu, p. 701 «t »tq.—
by the Author, and used in the clasR-room to £i>.
illustrate the doctrine of the text. — Ed.
LECTUKE IX.
STOIOHEIOLOOY.
SECTION II. — OF THE PRODUCTS OF THOUGHT.
I.— ENNOEMATIC.
B. OF CONCEPTS IN SPECIAL. — II. THEIR SUBJECTIVE RELA-
TION—QUALITY.
Having concluded the consideration of the relation of concepts
. to their objects, — the relation in which their
Relation of Concepts Quantity is given, — I now proceed to consider
to their subject. ; • i • \ • • • i • ,
their relation to their conceiving subject — the
relation in which is given their Quality. This consideration of the
quality of concepts does not, in my opinion, belong to the Doctrine
of Elements, and ought, in scientific rigor, to be adjourned alto-
gether to the Methodology, as a virtue or perfection of thought.
As logicians, however, have generally treated of it likewise undei
the former doctrine, I shall do so too, and commence with the fol-
lowing paragraph.
IT XXVII. A concept or notion is the unity in conscious-
ness of a certain plurality of attributes, and
Par. XXVU. The .. .i .i />
Quality Of Concept, 1*, conscqucutly, supposcs the powcr of
consists in its logical thinking thcsc, both separately and to-
perfeotion or imper- gethcr. But as there are many gradations
feotion. o , . -^ o
in the consciousness with which the charac-
ters of a concept can be thought severally and in conjunction,
there will consequently be many gradations in the actual Per-
fection or Imperfection of a notion. It is this perfection or
imperfection which constitutes the logical Quality of a con-
cept.^
It is thus the greater or smaller degree of consciousness which
accompanies the concept and its object, that determines its quality,
1 Krug, Logik, i 30. C£. Esser, Logik. j 46 «t seq, — Ed. ^
112 LOGIC. Lect.IX.
and according to which it is called logically perfect or logically
imperfect. Now, there may be distinguished two degrees of this
logical perfection, the nature of which is summarily expressed in the
following paragraph.
IF XXVIII. There are two degrees of
Par. XXVIII. The tJje logical perfection of concepts, — viz.,
ioL°oai Perfection and their Cleamess Qxxdi thciY Distinctness, imdi^
Imperfection of Con- conscqucntly, two oppositc dcgrccs of their
oepts, — their Clear- , . . o .• • . i •
ness and Distinct- correspondmg impcrfection, — viz., their
neas, and their Ob- Obscurity and their Indistinctness. These
Bcurity and India- /. ,.,. ,•, n .• j •
tinotness ^^'^^ qualities express the peiiection and im-
perfection of concepts in extremes. But
between these extremes there lie an indefinite number of inter-
mediate degrees.
A concept is said to be clear (clara), when the degree of
consciousness is such as enables us to distinguish it as a whole
from others ; and obscure {obscura), when the degree of con-
sciousness is insufficient to accomplish this. A concept is said
to be distinct {distincta, perspicua), when the degree of con-
sciousness is such as enables us to discriminate from each other
the several characters, or constituent parts of which the con-
cept is the sum ; and indistinct or confused (indistincta, con-
fusa, imperspicita), when the amount of consciousness requisite
for this is wanting. Confused (confusa), may be employed as
the genus including obscure and indistinct}
The expressions clearness and obscurity, and distinctness and
indistinctness, as applied to concepts, originally
Original application denote certain modifications of vision ; from
of the expressions ^.j^j^^^ ^|^_ ^^.^^^ analogically extended to the
clfarness, obscurity, etc. ... t /? ii
iiiusfrated by refer- Other scnscs, to imagination, and finally to
encc to vision. thought. It may, therefore, enable us the better
to comprehend their secondary application, to
consider their primitive. To Leibnitz" we owe the precise distinc-
tion of concepts into clear and distinct, and from him I borrow the
following illustration. In darkness — the complete obscurity of
night — we see nothing, — there is no perception, — no discrimina-
1 Compare Kriig, Logik, 31 (t seq.— ED. Essais,!. ii. ch. xxix. The illustration, how-
[niiflici', Logique, i 345 et seq. Kant, Kr. rf. r. ever, does not occur in either of these p»8-
Vernini/i, l\. ii.Trans Dial., art. i., p. 414,3d sages. It was probably borrowed from K rug,
ed. 1790.) Logik, i 81, and attributed to Leibnita by an
2 Sol- his Mulilationex dr. Cognitione, Vetilate oversight. — Ed.
tt Litis ( Ofxra, ed. Erdmann, p. 79), Nouveaux
lkct. IX. LOGIC. iia
tion of objects. As the light dawns, the obscurity diminishes, the
deep and uniform sensation of darkness is modified, — we are con-
scious of a change, — we see something, but are still unable to
distinguish its features, — we know not what it is. As the light
increases, the outlines of wholes begin to appear, but still not with
a distinctness sufficient to allow us to perceive them completely ;
but when this is rendered possible, by the rising intensity of the
light, we are then said to see clearly. We then recognize moun-
tains, plains, houses, trees, animals, etc., that is, we discriminate
these objects as wholes, as unities, from each other. But their
parts, — the manifold of which these unities are the sum, — their
parts still lose themselves in each other, they are still but indis-
tinctly visible. At length, when the daylight has fully sprung, we
are enabled likewise to discriminate their parts ; we now see dis-
tinctly what lies around us. But still we see as yet only the wholes
which lie proximately around us, and of these only the parts which
possess a certain size. The more distant wholes, and the smaller
parts of nearer wholes, are still seen by us only in their conjoint
result, only as they concur in making up that whole which is for us
a visible minimum. Thus it is, that in the distant forest, or on the
distant hill, we perceive a green surface ; but we see not the several
leaves, which in the one, nor the several blades of grass, which in
the other, each contributes its effect to produce that amount of
impression which our consciousness requires. Thus it is, that all
which we do perceive is made up of parts which we do not perceive,,
and consciousness is itself a complement of impressions, which lie
beyond its apprehension,^ Clearness and distinctness are thus only
relative. For between the extreme of obscurity and the extreme
of distinctness, there are in vision an infinity of intermediate de-
grees. Now, the same thing occurs in thought. For we may either
be conscious only of the concept in general, or we may also be con-
scious of its various constituent attributes, or both the concept and
its parts may be lost in themselves to consciousness, and only recog-
nized to exist by effects which indirectly evidence their existence.
The perfection of a notion, as I said, is contained in two degrees
or in two virtues, — viz., in its clearness and in its
earness an o distinctness ! and, of course, the opposite vices •
tcnnty as in concepts. . ' ' ' ^^
of obscurity and indistinctness afford two de-
grees or two vices, constituting its imperfection. "A concept is
said to be clear^ when the degree of consciousness by which it is-
accompanied is sufficient to discriminate what we think in and
through it, from what we think in and through other notions;.
1 See Lectures on Metaphysics, p. 241 tt uq. — Ed.
15
114 LOGIC. Lect. IX.
whereas if the degree of consciousness be so remiss that this Mid
other concepts run into each other, in that case the notion is said to
be obscure. It is evident that clearness and obscurity admit of
various degrees ; each being capable of almost infinite gradations,
according as the object of the notion is discriminated with greater
or less vivacity or precision froni the objects of other notions. A
concept is aJbsolutdy clear, when its object is
The absolutely clear distinguished from all Other objccts ; a concept
and absolutely ob- • i . 7 i 1 . , . ,
pjjjij^ IS <wsohitely obscure, when its object can be
di.stinguished from no other object. But it is
only the absolutely clear and the absolutely obscure which stand
opposed as contradictory extremes; for the same notion can at
once be relatively or comparatively clear, and relatively or com-
paratively obscure. Absolutely obscure notions, that is, concepts
whose objects can be distinguished from nothing else, exist only in
theory ; — an absolutely obscure notion being, in fact, no notion at
all. For it is of the very essence of a concept, that its object
should, to a certain degree at least, be comprehended in its peculiar,
consequently, in its distinguishing, characteristics. But, on the
oUier haild, of notions absolutely clear, that is, notions whose
objects cannot possibly be confounded with aught else, whether
known or unknown, — of such. notions a limited intelligence is pos-
sessed of very few, and, consequently, om* human concepts are,
properly, only a mixture of the opposite qualities ; — dear or obscure
as applied to them, meaning only that the one quality or the other
is the preponderant. In a logical relation, the illustration of notions
consists in the raising them from a preponderant obscurity to a pre-
ponderant clearness — or from, a lower degree to a higher."^ So
much for the quality of clearaess or obscurity considered in itself
me Di«tinctressand ^^^ ^ ^^^^^ concept may be either Distinct or
indutinctnessofCon- Indistinct; the distinctness and indistinctness
"*** of concepts are therefore to be considered apart
from' their clearness and obscurity.
But before entering upon the nature of the distinction itselij I
may observe that we owe the disciiraination of
Historical notice of Distinct and Indistinct from Clear and Obscure
this distinction. . t -i •
Due to Leibnitz. notions to the acutcncss of the great Leibnitz.
By the Cartesians the distinction had not been
taken ; though the authors of the Port lioyal Logic come so near,
that we may well marvel how they failed explicitly to enounce it.*
1 Eeser, pp. 91, 92, [Log-i'i, S 46. — Ed.] Descartes and Leibnitz, see the Appeudix to
2 Tart I. ch. i.v. — For a comparison of this Mr. Baynes's translation of the Tort Roytd
(tatcment of the distinction with those of Lo^'it, p. 423 (second edition). —Ed.
Lect. IX. LOGIC. 116
Though Locke published his Essay Concerning Human Under-
standing some five years subsequfent to the paper
in which Leibnitz — then a very young man —
had, among other valuable observations, promulgated this distinc-
tion, Locke did not advance beyond the limit already reached by
the Cartesians; indeed, the praises that are -so frequently lavished
on this philosopher for his doctrine concerning the distinctions of
Ideas, — the conditions of Definition, etc., — only prove that his
encomiasts are ignorant of what had been done, and, in many re-
spects, far better done, by Descartes and his school ; — in fact, with
regard to the Cartesian Philosophy in general, it must be confessed,
that Locke has many en-ors to expiate, arising partly from oversight,
and partly from the most unaccountable misapprehension of its doc-
trines. It is almost needless to say, that those who, in this country,
have written ourthis subject, posterior to Locke, have not advanced
a step beyond him ; for though Leibnitz be often mentioned, and
even occasionally quoted, by our British philosophers, I am aware
of none who possessed a systematic acquaintance with his philoso-
phy, and, I might almost say, who were even superficially versed
either in his own writings or in those of any of the illustrious think-
ers of his school. , {xj ,
But to consider the distinction in itself We have seen that, a
concept is clear, wheft we are able to recognize
distinction in
itself.
IS inc ion n it as different froni Other concepts. But we may
discriminate a whole from other wholes, we may
discriminate a concept from other concepts, though we have only a
confused knowledge of the parts of which that whole, or of the
characters of which that concept, is made up. This may be illus-
trated by the analogy of our Perceptive and
Illustrated by the Representative Faculties. We are all acquainted
analogy of Perception ., , -.,..,, ,.
and Representation. ^ith many,, say a thousand, individuals ; that is,
we recognize such and such a countenance as
the countenance of John, and as not the countenance of James,
Thomas, Richard, or any of the other 999. This we do with a clear
and certain knowledge. But the countenances, which we thus dis-
tinguish from each other, are, each of them, a complement made up
of a great number of separate traits of featui-es ; and it might, at
first view, be supposed that, as a whole is. only the sum of its parts,
a clear cognition of a whole countenance can only be realized
through a distinct knowledge of each of its constituent features.
But the slightest consideration will prove that this is not the case.
For how few of us are able to say of any, the most familiar face,
what are the particulai- traits which go to form the general result ;
116 LOGIC. Lect. IX.
and yet, on that account, we hesitate neither in regard to our own
knowledge of an individual, nor in regard to the knowledge pos-
sessed by others. Suppose a witness be adduced
The judicial deter- . ^ i? • a.- ^ xi • i •
mination betweeniife .^^ » ^^^^^ of justice to prove the identity Or non-
and death supposes identity of a certain individual with the perpe-
the difference between trator of a certain Crime, the commission of
a clear and distinct i_'t.'u-lji_ 3 ^ ii.i
which he had chanced to see, — would the coun-
knowledge. '
sel be allowed to invalidate the credibility of the
witness by, first of all, requiring him to specify the various elements
of which the total likeness of the accused was compounded, and
then by showing that, as the witness either could not specify the
several traits, or specified what did not agree with the features of
the accused, he was, therefore, incompetent to prove the identity or
non-identity required ? This would not be allowed. For the court
would hold that a man might have a clear perception and a clear
representation of a face and figure, of which, however, he had not
separately considered, and could not separately image to himself^
the constituent elements. Thus, even the judicial determination of
life and death supposes, as real, the difference between a clear and
a distinct knowledge : for a distinct knowledge lies in the knowl-
edge of the constituent parts ; while a clear knowledge is only of
the constituted whole.
Continuing our illustra'tions from the human countenance : we
all have a clear knowledge of any face which we
Further illustration j^^^g ggg„^ ^^^^ f^^ ^f ^^ ]^^^q distinct knowl-
from the human coun- . „ . * 1 1 • 1 n •^•
j^jj^j^^g edge even of those with which we are lamiliar ;
but the painter, who, having looked upon a
countenance, can retire and reproduce its likeness in detail, has
necessarily both a clear and a distinct knowledge of it. Now, what
is thus the case with perceptions and representations, is equally the
case with notions. We may be able clearly to discriminate one
concept from another, although the degree of consciousness does
not enable us distinctly to discriminate the various component char-
acters of either concept from each other. The Clearness and the
Distinctness of a notion are thus not the same ; the former involves
merely the power of distinguishing the total objects of our notions
from each other; the latter involves the power of distinguishing the
several characters, the several attributes, of which that object is
the sum. In the former the unity, in the latter the multiplicity,
of the notion is called into relief.
The distinctness of a concept supposes, however, the Clearness ;
and may, therefore, be regarded as a higher degree of the same
quality or perfection. "To the distinctness of a notion, over and
LeCT. IX. LOGIC. IIV
above its general clearness, there are required three conditions, —
1°, The clear apprehension of its several char-
Speciaiconditionflof acters or Component parts; 2°, The clear con-
the Distinctness of a ^^^^ ^^ discrimination of these: and, 3°, The
Concept, and of its . . ,
^ ,^^ clear recognition oi the nexus by which the
several parts are bound up into a unity or whole.
" As the clearness, so the distinctness, of a notion is susceptible
of many degrees. A concept may be called distinct^ when it in-
volves the amount of consciousness i-equired to discriminate fi'om
each other its principal characters ; but it is so much the more dis-
tinct, 1°, In proportion to the greater number of the characters
apprehended ; 2°, In proportion to the greater clearness of their
discrimination ; and, 3°, In proportion to the precision with which
the mode of their connection is recognized. But the greater dis-
tinctness is not exclusively or even principally determined by the
greater number of the clearly apprehended characters ; it depends
still raoi-e on their superior importance. In particular, it is of mo-
ment whether the characters be positive or negative, internal or
external, permanent or transitory, peculiar or common, essential or
accidental, original or derived. From the mere consideration of the
differences subsisting between attributes, there emerge three rules
to be attended to in bestowing on a concept its requisite distinct-
ness. In the first place, we should endeavor to discover the posi-
tive characters of the object conceived; as it is our purpose to
know what the object is, and not what it is not. When, however,
as is not unfrequently the case, it is not at once easy to discover
what the positive attributes are, our endeavor should be first di-
rected to the detection of the negative ; and this not only because
it is always an advance in knowledge, when we ascertain what an
object is not, but, likewise, because the discovery of the negative
characters conducts us frequently to a discovery of the positive.
^ In the second place, among the positive qualities we should seek
out the intrinsic and permanent before the extrinsic and transitory ;
for the former give us a purer and more determinate knowledge of
an object, though this object may likewise, at the same time, pre-
sent many external relations and mutable modifications. Among
the permanent attributes, the proper or peculiar always merit a
preference, if for no other reason, because through them, and not
through the common qualities, can the proper or peculiar nature of
ihc object become known to us.
"In the third place, among the permanent characters we ought
first to hunt out the necessary or essential, and then to descend
from them to the contingent or accidental; and this is not only
1-3 LOGIC. Lect. IX
because we thus give order and connection to our notions, but,
likewise, because the contingent characters are frequently only to
be comprehended through the necessary."^
But before leaving this part of our subject, it may be proper to
illustrate the distinction of Clear and Distinct
The distinction of notions by one or two concrete examples. Of
Clear and Distinct no- ,•■• ■■ , i.^.^-.-^-
ti ns illustrated b i"any things We havo clear but not distinct no-
eoacrete examples. tions. Thus, we have a dear, but not a distinct,'
notion of colors, sounds, tastes, smells, etc. For
we are fully able to distinguish red from white, to distinguish an
acute from a grave note, the voice of a friend from that of a stran-
ger, the scent of roses from that of onions, the flavor of sugar from
that of vinegar; but by what plurality of separate and enunciable
characters is this discrimination made? It is because we are unable-
to do this, that we cannot describe such perceptions and represen-
tations to others.
*'If you ask of me," says St. Augustine, "what is Time, I knoW^
not; if you do not ask me, I know."^ What does this mean?
Simply that he had a clear, but not a distinct, notion of Time.
Of a triangle we have a clear notion, when we distinguish a tri-
angle from other figures, without specially considering the charao^
ters which constitute it what it is. But when we think it as a por-
tion of space bounded by three lines, as a figure whose three angleR
are equal to two right angles, etc., then we obtain of it a distinct
concept.
We now come to the consideration of the question, — How doea
the Distinctness of a concept stand aflfected by
How the Distinctness .1, ^•,. /. ^ n i • f
',■ -^ ,. ». , J the two quantities of a concept .'' — and in ret-
of a Concept 18 affected ^ '■
by the two quantities erence to this point I would, in the first place,
of a Concept. dictate to you the following paragraph :
% XXIX. As a concept is a plurality of characters bound up
into unity, and as that plurality is contained
Pap. XXIX. Distinct. partly in its Intensive, partly under its Ex-
ness. Internal and £x- ^ . ■ ..^ .^ -rx* .* ^ • • 1-1
^^j^^i tensive, quantity, its Distinctness is, m lik*'
manner, in relation to' these quantitie^^
partly an Internal or Intensive, partly an external or Extensive'
Distinctness.'
In explanation of this, it is to be observed, that, as the distinct-
ness of a concept is contained in the clear apprehension of the
I Kwer, Loglk, f 47, p 93-95. — Ed. » Kmg, Logik, f S(; EsBer, Logik, J «. -
» Cdn/i««<»M,'xi. c; 14.--El>. Bb.
Lbct. IX LOGIC. 119
various attributes of which it is the sum, as it is the sum of these
attributes in two opposite relations, which con-
£xplicatioii. . . „ .
stitute, m lact, two opposite quantities or wholes,
and as these wholes are severally capable of illustration by analysis,
it follows, that each of these analyses will contribute its peculiar
share to the general distinctness of the concept. Thus, if the dis-
tinctness of a notion bears reference to that plurality which consti-
tutes its comprehension, in other words, to that which is contained
in the concept, the distinctness is denominated an internal or in-
tensive distinctness, or distinctness of comprehensio7i. On the other
hand, if the distinctness refers to that plurality which constitutes
the extension of the notion, in other words, to what is contained
under it, in that case, the distinctness is called an external or exten-
sive distinctness, a distinctness of extension. It is only when a
notion combines in it both of these species of distinctness, it is only
when its parts have been analyzed in reference to the two quan-
tities, that it reaches the highest degree of distinctness and of per-
fection.
The Internal Distinctness of a notion is accomplished by Exposi-
tion or Definition, that is, by the enumeration
Definition and Divi- ^^ ^^^q characters or partial notions contained in
sion .
it ; the External Distinctness, again, of a notion
is accomplished through Division, that is, through the enumer-
ation of the objects which are contained under it. Thus the con-
cept man is rendered intensively more distinct, when we declare
that man is 2i rational animal ; it is rendered extensively more dis-
tinct, when we declare that man is partly m.ale^ partly /emafe man}
In the former case, we resolve the concept man into its several
characters, — into its partial or constituent attributes ; in the latter,
we resolve it into its subordinate concepts, or inferior genera. In
simple notions, there is thus possible ah exten-
Simpie notions ad- sive, but not an intensive, distinctness ; in indi-
mit of an extensive, yi^ual notions, there is possible an intensive,
individual notions of . ,. . „ r^^^ ^
an intensive, distinct- t)ut not an extensive, distinctness.2 Thus the
ness. concepts existence, green, sweet, etc., though, as
absolutely or relatively simple, their compre-
hension cannot be analyzed into any constituent attributes, and they
do not, therefore, admit of definition ; still it cannot be said that
they are incapable of being rendered more distinct. For do we not
analyze the pluralities of which these concepts are the sum, when
we say, that existence is either ideal or real, that green is a yellowish
1 King, p. 95, iLogik, } 31. — Ed.] 3 Easer, Logik, § 48. — Ed.
120' LOGIC. Lbct. IX.
or a bluish green, that sweet is a pungent or a mawkish sweet ? —
and do we not, by this analysis, attain a greater degree of logical
perfection, than when we think them only clearly and as wholes ? '
"A concept, has, therefore, attained its highest
The highest point of point of distinctness, when there is such a con-
Distiuctness of a Con- . r- -^ t . .1 ^ • !••>.
sciousness 01 its characters that, m rendenng its
comprehension distinct, we touch on notions
which, as simple, admit of no definition, and, in rendering its exten-
sion distinct, we touch on notions which, as individual, admit of no
ulterior division. It is true, indeed, that a distinctness of this
degree is one which is only ideal ; that is, one to which we are
always approximating, but which we never are able actually to
reach. In order to approach as near as possible to this ideal, we
must always inquire, what is contained in, and what under, a notion,
and endeavor to obtain a distinct consciousness of it in both rela-
tions. What, in this research, first presents itself we must again
analyze anew, with reference always both to comprehension and
to extension ; and descending from the higher to the lower, from
the greater to the less, we ought to stop only when our process is
arrested in the individual or in the simple.'' *
1 Emg, Logik, f Si, Anmerk., i. pp. 95, 96. — Ed. " Ha^er, Logik, i 48, p. 96. -^1»
LECTURE X.
STOICHEIOLOGY.
SECTION II. — OF THE PRODUCTS OF THOUGHT.
I. — EKNOEMATIC.
IMPERFECTION OF CONCEPTS.
It is now necessary to notice an Imperfection to which concepts
are peculiarly liable, and in the exposition of
Imperfection of Con- i • i x ^ j •>. , i
^^ which 1 nnd it necessary to employ an expres-
sion, which, though it has the highest philosoph-
ical authority for its use, I would still, in consequence of its ambiguity
in English, have avoided, if this could have been done without
compromising the knowledge of what it is intended to express.
The expression I mean, is intuitive, in the particular signification in
which it is used by Leibnitz,^ and the continental philosophers in
general, — to denote what is common to our direct and ostensive
cognition of individual objects, in Sense or Imagination (Presen-
tation or Representation), and in opposition to our indirect and
symbolical cognition of general objects, through the use of signs or
language, in the Understanding. But, on this head, I would, first
of all, dictate to you the following paragraph.
% XXX. As a notion or concept is the factitious whole or
unity made up of a plurality of attributes,
fe!«on.''o1coacTpt"" " ^ .^^^^^ ^^^^ ^^^^ ""^ ^ ^^''^ COmplcx
multiplicity ; and as this piultiplicity is only
mentally held together, inasmuch as the concept is fixed and
ratified in a sign or word; it frequently happens, that, in its
employment, the word does not. suggest the whole amount of
thought for which it is the adequate expression, but, on the
contrary, we frequently give and take the sign, either with an
1 Meditationes de Cognitione, Veritate ct Tdeis, Opera, ed. Erdmann, p. 80. — Ed.
16
122 LOGIC. Lect. X.
obscure or indistinct consciousness of its meaning, or even
without an actual consciousness of its signification at alL
This liability to the vices of Obscurity and Indistinctness arises,
1°, From the very nature of a concept, which is
^ ****' the binding up of a multiplicity in unity ; and
2°, From its dependence upon language, as the necessary condition
of its existence and stability. In consequence of this, when a
notion is of a very complex and heterogeneous composition, we are
frequently wont to use the term by which it is denoted, without a
clear or distinct consciousness of the various characters of which
the notion is the sum ; and thus it is, that we both give and take
words without any, or, at least, without the adequate complement
of thought. I may exemplify this : You are aware, that in coun-
tries where bank-notes have not superseded the use of the precious
metals, large payments are made in bags of money, purporting to
contain a certain number of a certain denomination of coin, or, at
least, a certain amount in value. Now, these bags are often sealed
up and passed from one person to another, without the tedious pro-
cess, at each transference, of counting out their contents, and this
upon the faith, that, if examined, they will be found actually to
contain the number of pieces for which they are marked, and for
which they pass current. In this state of mattei-s, it is, however,
evident, that many errors or frauds may be committed, and that a
bag may be given and taken in payment for one sum, which con-
tains another, or which, in fact, may not even contain any money at
all. Now the case is similar in regard to notions. As the sealed
bag or rouleau testifies to the enumerated sum, and gives unity to
what would otherwise be an unconnected multitude of pieces, each
only representing its separate value ; so the sign or word proves and
ratifies the existence of a concept, that is, it vouches the tying up of
a certain number of attributes or characters in a single concept, —
attributes which would otherwise exist to us only as a multitude of
separate and unconnected representations of value. So far the
analogy is manifest; but it is only general. The bag, the guaran-
teed sum, and the constituent coins, represent in a still more proxi-
mate manner the term, the concept, and the constituent characters.
For in regard to each, we may do one of two things. On the one
hand, we may test the bag, that is, open it, and ascertain the accu-
racy of its stated value, by counting out the pieces which it pur.
ports to contain ; or we may accept and pass the bag, without such
a critical enumeration. In the other case, we may test the general
term, prove that it i& valid for the amount and quality of thought of
Lect. X LOGIC. 123
which it is the sign, by spreading out in consciousness the various
characters of which the concept professes to be the complement ; or
we may take and give the term without such an evolution.^
It is evident from this, that notions or concepts are peculiarly
liable to great vagueness and ambiguity, and that their symbols are
liable to be passed about without the proper kind, or the adequate
amount, of thought.
This interesting subject has not escaped the observation of the
philosophers of this country, and by them it
The liability to am- lias, in fact, with great ingenuity been illus-
biguity and vagueness ^^.^^^^ ^^^ ^^ ^^ ^^^ apparently ignorant
of concepts noticed by /. .» o
British piiiiosophers. that the matter had, before them, engaged the
attention of sundry foreign philosophei-s, by
whom it has been even more ably canvassed and expounded, I
shall, in the exposition of this point, also do justice to the illustrious
thinkers to whom is due the honor of having originally and most
satisfactorily discussed it.
The following passage from Mr. Stewart will afford the best foun-
dation for ray subsequent remarks : " In the
Stewart quoted on j^^^ section I mentioned Dr. Campbell as an in-
this subject. ^
genious defender of the system of the Nomin-
alists, and I alluded to a particular application which he has made
of their doctrine. The reasonings which I had then in view, are to
be found in the seventh chapter of the second book of his Philoso-
phy of Rhetoric^ in which chapter he proposes to explain how it
happens, ' that nonsense so often escapes being detected both by the
writer and the reader.' The title is somewhat ludicrous in a grave
philosophical work, but the disquisition to which it is prefixed, con-
tains many acute and profound remarks on the nature and power
of signs, both as a medium of communication, and as an instrument
of thought.
" Dr. Campbell's speculations with respect to language as an in-
strument of thought, seem to have been sug-
Kefers to Hume. _ , , ,. „ ' • ,r tt ,
gested by the loUowmg passage in Mr. Hume s
Treatise of Human Nature .'^ 'I believe every one who examines
the situation of his mind in reasoning, will agree with me, that we
do not annex distinct and complete ideas to every term we make
use of; and that in talking of Government, Church, Negotiation,
Conquest, we seldom spread out in our minds all the simple ideas
of which these complex ones are composed. It is, however, observ-
able, that notwithstanding this imperfection, we may avoid talking
1 A hint of this illustration is to be, found in Degerando, Dea Signes, vol. i. chap. viii. p.
200.-ED. SParti. J7. — Ed.
124 LOGIC. Lect. X.
nonsense on these subjects, and may perceive any repugnance
among the ideas, as well as if we had a fall comprehension of them.
Thus if, instead of saying, that in war the weaker have always re-
C/Ourse to negotiation, we should say, that they have always recourse
to conquest ; the custom which we have acquired, of attributing
certain relations to ideas, still follows the words, and makes us
immediately perceive the absurdity of that proposition.'
*' In the remarks which Dr. Campbell has made on this passage,
he has endeavored to explain in what manner our habits of thinking
and speaking gradually establish in the mind such relations among
the words we employ, as enable us to carry on processes of reason-
ing by means of them, without attending in every instance to their
particular signification. With most of his remarks on this subject
I perfectly agree; but the illustrations he gives of them are of too
great extent to be introduced here, and I would not wish to run
the risk of impairing their perspicuity by attempting to abridge
them. I must, therefore, refer such of my readers as wish to pros-
ecute the speculation, to his very ingenious and philosophical
treatise.
" ' In consequence of these circumstances,' says Dr. Campbell, ' it
happens that, in matters which are perfectly
And Campbell. ^ .,. , , ,
familiar to us, w^e are able to reason by means
of words, without examining, in every instance, their signification.
Almost all the possible applications of the terms (in other words,
all the acquired relations of the signs) have become customary to
us. The consequence is, that an unusual application of any term
is instantly detected ; this detection breeds doubt, and this doubt
occasions an immediate recourse to ideas. The recourse of the
mind, when in any degree puzzled with the signs, to the knowledge
it has of the things signified, is natural, and on such subjects per-
fectly easy. And of this recourse the discovery of the meaning,
or of the unmeaningness of what is said, is the immediate effect.
But in matters that are by no means familiar, or are treated in an
uncommon manner, and in such as are of an abstruse and intricate
nature, the case is widely different.' The instances in which we
are chiefly liable to be imposed on by words without meaning, are
(according to Dr. Campbell) the three following:
"•First, When there is an exuberance of metaphor.
^Secondly, When the terms most frequently occurring denote
things which are of a complicated nature, and to which the mind
is not sufficiently familiarized. Such are the words — Government,
Church, State, Constitution, Polity, Power, Commerce, Legislature,
Jurisdiction, Pioportion, Symmetry, Elegance.
Lect. X. LOGIC. 125
'-'■ Thirdly, "When the terms employed are very abstract, and con
sequently of very extensive signification.
"'The more general any word is in its signification, it is the more
liable to be abused by an improper or unmeaning application. A
very general term is applicable alike to a multitude of diflferent
individuals, a particular term is applicable but to a few. When the
rightful applications of a word are extremely numerous, they can-
not all be so strongly fixed by habit, but that, for greater security,
we must perpetually recur in our minds from the sign to the notion
we have of the thing signified ; and for the reason aforementioned,
it is in such instances diflUcult precisely to ascertain this notion.
Thus the latitude of a word, though different from its ambiguity,
hath often a similar effect.'"^
Now, on this I would, in the first place, observe, that the credit
;tj z.T attributed to Hume by Dr. Campbell and Mr.
Locke anticipated Stewart, as having been the first by whom the
Hume in remarking observation had been made, is, even in relation
the employment of -n • • i i m i tt i
terms without distinct to British philosophers, not Correct. Hume has
meaning. Stated nothing which had not, with equal em-
phasis and an equal development, been previ-
ously stated by Locke, in four difierent places of his Essay. '^
Thus, to take only one out of at least four passages directly to the
same efiect, and out of many in which the same is evidently main-
tained, he says, in the chapter entitled — Of the Abuse of Words:
"Others there be, who extend this abuse still
Locke quoted. /. , , , ,. , , , ,
larther, who take so little care to lay by words,
which in their primary notation have scarce any clear and distinct
ideas which they are annexed to, that by an unpardonable negli-
gence they familiarly use words, which the propriety of language
has fixed to very important ideas, without any distinct meaning at
all. Wisdom, glory, grace, etc., are words frequent enough in
every man's mouth • but if a great many of those who use them
should be asked what they mean by them, they would be at a stand,
and not know what to answer: a plain proof, that though they have
learned those sounds, and have them ready at their tongue's end,
yet there are no determined ideas laid up in their minds, which are
to be expressed to others by them. Men having been accustomed
fi^om their cradles to learn words, which are easily got and retained,
before they knew, or had framed the complex ideas to which they
were annexed, or which were to be found in the things they were
1 Elements, voL I., TTorfcs, vol. ii. chap. iv. 5 2 Compare Essay, B. ii., ch. xxii , § 7; ii.,
4, pp 193,165. jcxix. 9; ii. xxxi. 8; iii- ix. 6; iii.,x.2. — En
126 LOGIC. Lect. X.
thought to stand for, they usually continue to do so all their lives ;
and without taking the pains necessary to settle in their minds de-
termined ideas, they use their words for such unsteady and confused
notions as they have, contenting themselves w ith the same words
other people use : as if their very sound necessarily cai-ried with it
constantly the same meaning. This, though men make a shift with,
in the ordinary occurrences of life, where they find it necessary to be
understood, and therefore they make signs till they are so ; yet this
insignificancy in their words, when they come to reason concerning
either their tenets or interest, manifestly fills their discourse with
abundance of empty, unintelligible noise and jargon, especially in
moral matters, where the words, for the most part, standing for
arbitrary and numerous collections of ideas, not regularly and per-
manently united in nature, their bare sounds are often only thought
on, or at least very obscure and uncertain notions annexed to
them. Men take the words they find in use among their neighbors,
and that they may not seem ignorant what they stand for, use them
confidently, without much troubling their heads about, a .certain
fixed meaning : whereby, besides the ease of it, they obtain this
advantage, that as in such discourses they are seldom in the right,
80 they are as seldom to be convinced that they are in the wrong ; it
being all one to go about to draw those men out of their mis-
takes, who have no settled notions, as to dispossess a vagrant of
his habitation who has no settled abode. This I guess to.be so;
and eveiy one may observe in himself and others, whether it be or
no.">
From a comparison of this passage with those I have given you
from Stewart, Campbell, and Hume, it is manifest that, among Brit-
ish philosophers, Locke is entitled to the whole honor of the obser-
vation: for it could easily be shown, even from the identity of
expression, that Hume must have borrowed it from Locke; and
of Hume's doctrine the two other philosophers profess only to be
expositors.
This curious and important observation was not, however, firet
made by any British philosopher ; for Leibnitz
The distinction of \^r^^ jjot Only anticipated Locke, in a publication
Vk'^^wLd ^"fi* t prior to the Essay, but afforded the most pre-
taken by Leibnitz. <5ise and universal explanation of the phaenome-
non, which has yet been given.
To him we owe the memorable distinction of our knowledge into
Intuitive and Symbolical, in which distinction is involved the expla-
I Enay conctming Humcui Understanding, vol. ii. p. 228; [B. III., ch. x. f| 3, 4 — ED.]
Lect. X. LOGIC. 127
nation of the phaenomenon in question. It is the establishment of
this distinction, likewise, which has superseded
This distinction lias in Germany the whole controversy of Nominal-
superseded the contro- jgj^ jjjjjj Conceptualism, — which, in consequence
^^T^, X .• . of the non-establishment of this distinction, and
and Conceptualism in '
Germany. the relative imperfection of our philosophical
language, has idly agitated the Psychology of
this country and of France.
That the doctrines of Leibnitz, on this and other cardinal points
of psychology, should have remained apparently
Unacqnaintance of unknown to every philosopher of this country,
the philosophers of j^ ^ ^^^^^^. ^^^ f^^^ ^^ wonder than of regret,
this country with the "
doctrines of Leibnitz. and is Only to be excused by the manner in
which Leibnitz gave his writings to the world.
His most valuable thoughts on the most important subjects were
generally thrown out in short treatises or letters, and these, for a
long time, were to be found only in partial col-
Manner in which he lections, and sometimes to be laboriously sought
«ive his writings to . ■,. t ^i • >.i_
-; out, dispersed as they were, in the various scien-
tific Journals and Transactions of every country
of Europe; and even when his works were at length collected, the
attempt of his editor to arrange his papers according to their sub-
jects (and what subject did Leibnitz not discuss?) was baffled by
the multifarious nature of their contents. The most important
of his philosophical writings — his Assays in refutation of Locke
— were not merely a ])ostliumous publication, but only published
after the collected edition of his Works by Dntens ; and this trea-
tise, even after its publication, was so little known in Britain, that
it remained absolutely unknown to Mr. Stewart — (the only British
philosopher, by the way, who seems to have had any acquaintance
Avith the works of Leibnitz) — until a very recent period of his life.
The matter, however, vrith which we are at- present engaged, was
discussed by Leibnitz in one of his very earliest writings ; and in a
paper entitled JDe Cognitione, Veritate, et Ideis,
#His paper, e og- published in the Acta EnuUtorum of 1684, we
nttione,Ventate,ft Jaeis ■* _
have, in the compass of two quarto pages, all
that has been advanced of principal importance in regard to the
peculiarity of our cognitions by concept, and in regard to the depen-
dence of our concepts upon language. In this paper, besides estab-
lishing the difference of Clear and Distinct knowledge, he enounces
the memorable distinction of Intuitive and Symbolical knowledge,
— a distinction not certainly unknown to the later philosophers of
this country, but which, from their not possessing terms in which pre-
128 LOGIC. Lect. X.
cisely to embody it, has always remained vague and inapplicable to
common use. Speaking of the analysis of complex notions, he says :
"For the most part, however, especially in an
Leibnitz quoted on analysis of any length, we do not view at once
Intuitive and Symbol- , • i • > \ > ■, ^ i
ic 1 kno 1 d e (non smiul intuemur) the whole characters or
attributes of the thing, but in place of these we
employ signs, the explication of which into what they signify, we are
wont, at the moment of actual thought, for the sake of brevity, to
omit, knowing or believing that we have this explication always in
our power. Thus, when I think a chiliogon (or polygon of a thou-
sand equal sides), I do not always consider the various attributes,
of the side, of the equality, and of the number a thousand, but use
these words (whose meaning is obscurely and imperfectly presented
to the mind) in lieu of notions which I have of them, because I
remember, that I possess the signification of these words, though
their application and explication I do not at present deem to be
necessary: — this kind of thinking I am used to call blind or sym-
bolical: we employ it in Algebra and in Arithmetic, but in fact
universally. And certainly, when the notion is very complex, we
cannot think at once all the ingredient notions : but where this is
possible — at least, inasmuch as it is possible — I call the cognition
intuitive. Of the primary elements of our notions, there is given
no other knowledge than the intuitive : as of our composite notions,
there is, for the most part, possible only a symbolical. From these
considerations it is also evident, that of the things which we dis-
tinctly know we are not conscious of the ideas, except in so far
as we employ an intuitive cognition. And, indeed, it happens
that we often falsely believe that we have in our mind the ideas
of things ; erroneously supposing, that certain terms which we em-
ploy, had been applied and explicated ; and it is not true, at least
it is ambiguously expressed, what some assert, — that we cannot
speak concerning anything, understanding what we say, without
having an idea of it actually present. For we frequently npply .any
kind of meaning to the several words, or we merely recollect us,
that we have formerly understood them, but because we are content
with this blind thinking, and do not follow out the resolution of
the notions, it happens, that contradictions are allowed to lie hid,
which perchance the composite notion involves." ..." Thus, at
.first sight, it must seem, that we could form an idea of a maximum
velocity (motus c«lerrimi), for in using the terms we understand
what we say ; we shall find, however, that it is impossible, for the
notion of a quickest motion is shown to be contradictory, and,
therefore, inconceivable. Let us suppose, that a wheel is turned
I
Lect. X. LOGIC. 129
with a velocity absolutely at its maximum ; every one perceives
that if one of its spokes be produced, its outer end will be moved
more rapidly than the nails in the circumference of the wheel ; the
motion, therefore, of these is not a maximum, which is contrary to
the hypothesis, and, therefore, involves a contradiction.."
This quotation will suffice to show you how correctly Leibnitz ap-
prehended the nature of concepts, as opposed to
Effect of this distinc- the presentations and representations of the sub-
tion by Leibnitz on gidiary facilities ; and the introduction of the term
the philosophy of Ger- „ 77. ti it . t • .1 n
^ Symoohcal knowledge, to designate the former,
and the term Intuitive knowledge to comprehend
the two latter, — terms which have ever since become classical in his
own country, — has bestowed on the German language of philosophy,,
in thisj-espect, a powerand precision to which that of no other nationi
can lay claim. In consequence of this, while the philosophers of
this country have been all along painfully expounding the phienom-
enon as one of the most recondite arcana of psychology, in Germany
it has, for a century and a half, subsided into one of the elementary
doctrines of the science of mind. It was in consequence of the
establishment of this distinction by Leibnitz, that a peculiar expres-
sion {Begriff, conceptus) was appropriated to the symbolical notions
of the Understanding, in contrast to the intuitive presentations of
Sense and representations of Imagination, which last also were fur--
nished with the distinctive appellations of intuitio7is (Anschauun- .
gen, intuitus). Thus it is, that, by a more copious and well-ap-
pointed language, philosophy has, in Germany, been raised above
various controversies, which, merely in consequence of the poverty
and vagueness of its English nomenclature, have idly occupied out
speculations. But, to return to the^mere logical question.
The doctrine of Leibnitz in regard to this natural imperfection of
our concepts was not overlooked by his disciples, .
The distinction ap- ^^^ j shall read you a passage from the Lesser
pies of Leibnitz. Logic of Wolf, — a work abovc a century old, and "
which was respectably translated from <jermaii'
into Engl'gb '" *^f^ y^"'' ^ '^'^'\j This translation is now rarely to be met
with, which may account for its being apparently totally unknown tO'
our British philosophers; and yet, upon the whole, with all its faults-
and imperfections, it is perhnps the most valuable work on Logic (to-
say nothing of the Port Royal Logic) in the English language.
"By Words, we usually make known our
o quoec. or » thoughts to Others: and thus they are nothing
or terms. — what. ° _ _ •' • °
but uttered articulate signs of our thoughts for
the information of others: for exnmple, if one asks me what I am,
17
130 LOGIC. Lect. X.
thinking of, and I answer, the sun ; by this word I acquaint him
what object my thoughts are then employed about.
" If two persons, therefore, are talking together, it is requisite, in
order to be understood, first, that he who speaks, shall join some
notion or meaning to each word ; secondly, that he who hears, shall
join the very same notion that the speaker does.
" Consequently, a certain notton or meaning must be connected
with, and therefore something be signified by, each word.
" Now, in order to know whether we understand what we speak,
or that our words are not mere empty sound, we ought, at every
word we utter, to ask ourselves what notion or meaning we join
therewith.
" For it is carefully to be observed, that we have not always the
notion of the thing present to us, or in view,
infpeakingorthink- when we spcak or think of it; but are satisfied
ing, le meaning o when wc imagine we suflSciently understand
words not always ° •'
attended to. what we speak, if we think we recollect that
we have had at another time the notion which
is to be joined to this or*the other word ; and thus we represent to
ourselves, as at a distance only, or obscurely, the thing denoted
by the term (§ 9, c. i.).
" Hence it usually happens, that when we combine words to-
gether, to each of which apart a meaning or
How words without notion answcrs, we imagine we understand what
r^^t'od ™*'^ ^^® utter, though that which is denoted by such
combined words be impossible, and, consequently,
can have no meaning; for that which is impossible is nothing at all ;
and of nothing there can be no idea. For instance, we have a
notion of gold, as also of iron : but it is impossible that iron can, at
any time, be gold; consequently neither can we have any notion
of iron-gold ; and yet we understand what people mean when they
mention iron-gold.
" In the instance alleged, it certainly strikes every one at first
that the expression iron-gold \& an empty sound:
Further proved. , ,^ , ^ ^ , . . . . .
but yet there are a thousand instances m which it
does not so easily strike : For example, when I say a rectilineal two-
line figure, contained under two right-lines, I am equally well under-
stood as when I say a right-lined tiiangle, a figure contained under
three right-lines: and it should seem we had a distinct notion of
both figures (§ 13, c. i.). However, as we show in geometry that
two right-lines can never contain a space, it is also impossible to
form a notron of a rectilineal two-lined figure ; and, consequently,
that expression is an empty sound. Just so it holds with the vege-
Lect. X. LOGIC. 131
table soul of plants, supposed to be a spiritual being, whereby
plants are enabled to vegetate and grow: for though those words
taken apart are intelligible, yet in their combination they have no
manner of meaning. Just so if I say that the Attractive Spirit, or
Attractive Cord, as Linus calls it, or the Attractive Force, as some
philosophers at this day, is an immaterial principle superadded to
matter, whereby the attractions in nature are performed ; no notion
or meaning can possibly be joined with these words. To this head
also belong the Natural Sympathy and Antipathy of Plants ; the
Band of Right or law {vinculum juris), used in the definition of
Obligation, by Civilians ; the principle of Evil of the Manicheans,"
etc'
1 Logic, or Rational Thoughts on the Powers of the German of Baron Wolfius, C. il., p. 54 — 67;
the Human UntiersUuuiing. Transiated from London, 1770.— £d.
LECTUEE XI.
STOICHEIOLOOY.
SECTION I.— OF THE PRODUCTS OF THOUGHT.
I. ENNOEMATIC.
ni. RECIPROCAL RELATIONS OF CONCEPTS.
QUANTITY OF EXTENSION — SUBORDINATION AND CO-
ORDINATION.
I NOW proceed to the third and last Relation of Concepts, — that
of concepts to each other. The two former relations of notions —
to their objects and to their subject — gave their Quantity and Qual-
ity. This, the relation of notions to each other, gives what is
emphatically and strictly denominated their Relation. In this rig-
orous signification, the Relation of Concepts may be thus defined.
^ XXXI. The Relation proper of notions consists in those
determinations or attributes which belong
Par. XXXI. Beeip- ^q them, not vicwcd as apart and in them-
rocal Belations of . i /-^
Concepts. ' sclvcs, but US rcciprocally compared. Con-
cepts can only be compared together with
reference, either, 1°, To their Extension ; or, 2°, To their Com-
prehension. All their relations are, therefore, dependent on the
one or on the other of these quantities.*
^ XXXII. As dependent upon Extension, concepts stand
to each other in the five mutual relations,
i^lnif^' """""^ 1°. Of Exclusion ; 2°, Of Coextension ; 3°,
Of Subordination ; 4°, Of Coordination ; and
5°, Of Intersection.
1. One concept excludes another, when no part of the one
coincides with any part of the other. 2. One concept is coex-
1 Cf. Krug, Logik, ) 36. — Ed. S See diagram, p. 133.
Lect. XI.
LOGIC.
133
CONCEPTS, THEIR RELATIONS PROPER
1 Exelosionl
2. CoSxtension
8. Sabordinatioa
4. Coiirdination
6. Intersection, or
Partial Coinclu-
sion and CoSx-
elusion.
lOWlT OF
I I I.
I I
©
1 The notation by straight lines was first employed by the author in 184S. — Ed.
134 LOGIC. Lkct. X£
tensive with another, when each has the same number of sub-
ordinate concepts under it. 3. One concept is subordinate to
another (which may be called the Superordiiiate) when the
former is included within, or makes a part of, the sphere or
extension of the latter. 4. Two or more concepts are coordi-
nated, when each excludes the other from its sphere, but when
both go immediately to make up the extension of a third con-
cept, to which they are cosubordinate. 5. Concepts intersect
each other, when the sphere of the one is partially contained
in the sphere of the other.'
Of Exclusion, horse, syllogism, are examples : there is no abso-
lute exclusion.
Examples of the five ^^ examples of Coextension,— the concepts
mutual relations of . , . . t » .
Concepts. livinff, detnff, and orf/amzed beings, may be
given. For, using the term life as applicable to
plants as well as animals, there is nothing living which is not organ-
ized, and nothing organized which is not living. This reciprocal
relation will be represented by two circles covering each other, or
by two lines of equal length and in positive relation.
As examples of Subordination and Coordination, — man, dog,
horse, stand, as correlatives, in subordination to the concept animal,
and, as reciprocal correlatives, in coordination with each other.
What I would call the reciprocal relation of Intersection, takes
place between concepts when their spheres cross or cut each other,
that is, fall partly within, partly without, each other. Thus, the
concept black and the concept heavy mutually intersect each other,
for of these some black things are heavy, some not, and some heavy
things are black, some not.
Of these relations, those of Subordination and
Subordination and Coordination are of principal importance, as on
Coordination of priii- , i -i i /^ i ...
oipai importance. ^^^^m reposes the whole system of clas.sitica-
tion; and to them alone it is, therefore, neces-
sary to accord a more particular consideration.
Under the Subordination of notions, there are various terms to
express the different modes of this relation ;
Terms expressive of these it is necessary that you should now learn
the different modes of ji a. \ • • :i e ^t r-
_- . and hereafter bear m mind, for they lorm an
the relation of Subor- ^ < ' •' _
dination. essential part of the language of Logic, and Mill
come frequently, in the sequel, to be employed
in considering the analysis of Reasonings.
1 Cf. Krng; Lagik, f 41. —Ed.
Li;ci. XL LOGIC. 135
% XXXIII. Of notions which stand to each other in the
relations of Subordination, — the one is the
Par. XXXin. Supe- rr- i a • / ^- i.
rior and Inferior, Higher Or l^upenor {notio, conceptus, supe-
Broader and Narrow- riOV), the Other the LoweV OX InfeviOT
(notio, conceptus, iiiferior). The superior
notion is likewise called the Wider or broader (latior), the
inferior is likewise called the Narrower {angustior)}
The meaning of these expressions is sufficiently manifest. A
notion is called the higher or superior, inasmuch
Explication. . . . , ,. i • »
as it IS viewed as standing over another in the
relation of subordination, — as including it within its domain or
sphere ; and a correlative notion is called the lower or inferior, as
thus standing under a superior. Again, the higher notion is called
the wider or broader, as containing under it a greater number of
things ; the lower is called the narrower, as containing under it
a smaller number.
^ XXXIV. The higher or wider concept is also called, in
contrast to the lower or narrower, a JJni-
Par. XXXIV. Tini- i^ersal or General Notion (vo-naa koSoXov,
versal and Particular ^
notions. uotio, conceptus, Universalis, generuUs) ; the
lower or narrower concept, in contrast to
the higher or wider, a Particular Notion, vo-qjxa fx-epiKov, notio,
conceptus particularis?
The meaning of these expressions, likewise, requires no illustra-
tion. A notion is called universal, inasmuch as
it is considered as binding up a multitude of
parts or inferior concepts into the unity of a whole ; for universus
means in unum versus or ad unum versus, that is, many turned
into one, or many regarded as one, and universal is employed to
denote the attribution of this relation to objects. A notion is called
particular, inasmuch as it is considered as one of the parts of a
higher concept or whole.
^ XXXV. A superior concept, inasmuch as it constitutes a
common attribute or character for a number of inferior con-
cepts, is called a General Notion (vvq/xa koSoXov, notio conceptus
generalis), or, in a single word, a Genus (yeyos, genus). A
1 Cf. Krug, Logi'lc, § 42. — Ed. lati, Rudimenta Lo^ca, p. 39] [Logica, torn.
2 rSee Ammonius, In De Interpret., f 72 b., i., P. I., c. iv. § 8, 4th edit , Venice, 1772. C£
(Brandis, Scholia in Ari^cot., p. 113); Faccio- Krug, Logik, § 42. — Ed.]
136 LOGIC. Lect. XL
notion, inasmuch as it is considered as at once affording a com-
mon attribution for a certain complement
Par. ZXXV. Oenus /••x'- ^ •T-iii-^
and Species *^^ interior couccpts or individual objects,
and as itself an inferior concejit, contained
under a higher, is called a Special Notion (vorjfxa ctScKoV, notio,
conceptus, specialis), or, in a single word, a /Species (ttSos, spe-
cies). The abstraction which carries up species into genera, is
called, in that respect, Generijication, or, more loosely, Gener-
alization. The determination which divides a genus into its
species is called, in that respect. Specification. Genera and
Species are both called Classes ; and the arrangement of things
under them is, therefore. Classification.^
It is manifest that the distinction into Genera and Species is a
merely relative distinction ; as the same notion
Explication. The ig^ Jq one rcspect, a genus, in another respect, a
distinction of Genus igg. For except a notion has no higher
and Species merely ... o -
relative. notion, that is, except it be itself the widest or
most universal notion, it may always be regarded
as subordinated to another ; and, in so far as it is actually thus re-
garded, it is a species. Again, every notion except that which has
under it only individuals, is, in so far as it is thus viewed, a genus.
For example, the notion triangle, if viewed in relation to the notion
of rectilineal figure, is a species, as is likewise rectilineal figure
itself, as viewed in relation to figure simply. Again, the concept
triangle is a genus, when viewed in reference to the concepts, —
right-angled triangle, acute-angled triangle, etc. A right-angled
triangle is, however, only a species, and not possibly a genus, if
under it be necessarily included individuals alone. But, in point of
fact, it is impossible to reach in theory any lowest species ; for we
can always conceive some difference by which any concept may be
divided ad infinitum. This, however, as it is only a speculative
curiosity, like the infinitesimal divisibility of matter, may be thrown
out of view in relation to practice; and, therefore, the definition, by
Porphyry and logicians in general, of the lowest species (of which
I am immediately to speak), is practically correct, even though it
cannot be vindicated against theoretical objections. On the other
hand, we soon and eiisily renoh the highest genus, which is given in
TO 6v, ens aliquid, being, thing, something, etc., which are only vari-
ous expressions of the same absolute universality. Out of these
1 Krug. hoe:ik, S 43. — Ed.
I
Lect. XI. LOGIC. 137
conditions there arise certain denominations of conccitts, which it
is, likewise, necessary that you be made aware of.
In regard to the tei-nis Generification and Specification^ these are
limited expressions for the processes of Abstrac-
Generiflcation and ^j^^ ^^^^ Determination, considered in a particu-
iSpecitication, — what. . i -r>v • •
lar relation. Abstraction and Determination,
you will recollect, we have already spoken of in general;^ it will,
therefore, be only necessary to say a very few words in reference to
them, as the several operations by which out of species we evolve
genera, and out of genera we evolve species. And first, in regard
to Abstraction and Generification. In every
Generification. . t . . •
complex notion, we can limit our attention to its
constituent characters, to the exclusion of some one. We thus
think away from this one, — we abstract from it. Now, the concept
which remains, that is, the fasciculus of thought minus the one char-
acter which we have thrown out, is, in relation to the original, — the
entire concept, the next higher, — t^ie proximately superior notion.
But a concept and a next higher concept are to each other as species
and genus. The process of Abstraction, therefore, by which out of
a proximately lower we evolve a proximately higher concept, is,
when we speak with logical precision, called the process of Generi-
fication.
Take, for example, the concept man. This concept is proxi-
mately composed of the two concepts or constituent characters, —
animal and rational being. If we think either of these characters
away from the other, we shall have in that other a proximately
higher concept, to which the concept man stands in the relation of
a sj)ecies to its genus. If we abstract from animal, then man will
stand as a species in subordination to the genus rational being, and
the concept animal will then afford only a difference to distinguish
man as a coordinate species from immaterial intelligences. If, on
the other hand, we abstract from rational being, then man will
stand as a species in subordination to the genus animal, having for
a coordinate species irrational animal. Such is the process of
Generification. ISTow for the converse process of Specification.
Every series of concepts which has been obtained by abstraction,
may be reproduced in an inverted order, when.
Specification. i -■• r ., v.. . • i
descending irom the highest notion, we, step by
step, add on the several characters from which we had abstracted in
our ascent. This process, as you remember, is called Determina-
tion; — a very appropriate expression, inasmuch as by each charac-
1 See above, p. 87 et stq. — Ed.
18
138 LOGIC. Lect. XL
ter or attribute which we add on, we limit or determine, more and
more, the abstract vagueness or extension of the notion ; until, at
last, if every attribute be annexed, the sum of attributes contained
in the notion becomes convertible with the sum of attributes of
which some concrete individual or reality is the complement. Now,
when we determine any notion by adding on a suboi'dinate concept,
we divide it ; for the extension of the higher concepts is precisely
equal to the extension of the added concept plus its negation. Thus,
if to the concept animal we add on the next lower concept ratiom I,
we divide its extension into* two halves, — the one equal to rational
animal — the other equal to its negation, that is, to irrational ani-
7nal. Thus an added concept and its negation always constitute the
immediately lower notion, into which a higher notion is divided.
But as a notion stands to the notions proximately subordinate to it,
in the immediate relation of a genus to its species, the process of
Determination, by which a concept is thus divided, is, in logical
language, appropriately denominated Specification.
So much in general for the Subordination of notions, considered
as Genera and Species. There are, however, various gradations of
this relation, and certain terms by which these are denoted, which
it is requisite that you should learn and lay up in memory. The
most important of these are comprehended in the following para->
gi-aph :
% XXXVI. A Genus is of two degrees, — a highest and a
lowei". In its highest degree, it is called
Par XXXVI. Orada- ,, fv i^ ^ t^
tions of Genera and the Supreme or Most (jrcneral Genus {ytvot
Species, and their des. ycviKWTaTov, ffe?ius »umm,um, OY generalissi-
mum), and is defined, "that which being a
genus cannot become a si)ecies." In its lower degree, it is
called a Subaltern or Intermediate (ycvos vTraXkqKov^ genus sub-
altevnum or m,edium)y and is defined, " that which being a
genus can also becoine a species." A Species also is of two
degrees, — a lowest and a higher. In its lowest degree, it is
called a lowest or Jlost Special Species (JSo? tiSiKwraToi', species
infima, ultima^ or specialissima),^ and is defined, " that which
being a species cannot become a genus." In its higher degree,
it is called a Subaltern or Intermediate Species (eiSos trTroXXi^Xov,
species subalterna media), and is defined, " that which being a
.species may also become a genus." Thus a Subaltern Genus
and a Subaltern Species are convertible.
I vide Timpler, p. ?68 [TogiV* Ft/stftra, L ii c. J.q. 16— Ed.]
Lect. XI. LOGIC 139
The distinctions and definitions in this paragraph are taken from
the celebrated Introduction ^ of Porphyry to the
Categories of Aristotle, and they have been gen-
erally adopted by logicians. It is evident, that the only absolute
distinction here established, is that between the Highest or Supreme
Genus and the Lowest Species ; for the other classes — to wit, the
Subaltern or Intermediate — are, all and each, either genera or
species, according as we regard them in an ascending or a descend-
ing order, — the same concept being a genus, if considered as a
whole containing under it inferior concepts as parts, and a species,
if considered as itself the part of a higher concept or whole. The
distinction of concepts into Genus and Species, into Supreme and
Intermediate Genus, into Lowest and Intermediate Species, is all
that Logic takes into account ; because these are all the distinctions
of degree that are given necessarily in the form of thought, and as
abstracted from all determinate matter.
It is, however, proper here to say a word in regard to the Cat-
egories or Predicaments of Aristotle. These are
Categories of Aris- ^^^ ^^^^^^^ ^^^^ ^^^^^ Existence is divided,—
totle.
viz., 1, Substance; 2, Quantity; 3, Quality; 4,
Relation ; 5, Action ; 6, Passion ; 7, Where ; 8, When ; 9, Posture ;
and 10, Habit. (By this last is meant the relation of a containing
to a contained.) They are comprehended in the two following
verses :
Arbor, sex servos, fervore, refrigerat ustos,
Ruri eras stabo, nee tunicatus ero.2
In regard to the meaning of the word category, it is a term bor-
rowed from the courts of law, in which it lit-
Originai meaning erally signifies an accnsatioji. In a philosophical
and employment of application, it has two meanings, or rather it is
the term category. * ^ ^ , *^.
used in a general and m a restricted sense. In
its general sense, it means, in closer conformity to its original ap-
plication, simply a predication or attribution,' in its restricted
sense, it has been deflected to denote predications or attributions
of a very lofty generality, in other words, certain classes of a very
wide extension. I may here notice, that, in modern philosophy, it
has been very arbitrarily, in fact very abusively, perverted from
both its primary and its secondary signification among the ancients.
Aristotle first employed the term (for the supposition that he bor-
1 C ii., §§ 23, 28, 29. Facciolati, LogUa, [t. i., Rudimenta iMgica, V.
2 Murmellii Isagoge, c. i. Vide Micralius I. c. iii. p. 32. — Ed.]
{Lex. Phil. V. Prtedkamenta- Eo.] p. 1086.
140
LOGIC.
Lkct. XL
rowed his categories, name and thing, from the Pythagorean Archy-
las is now exploded — the treatise under the name of this philos-
opher being proved to be a comparatively recent forgery'), — I
say, Aristotle first employed the term to denote a certain classifica-
tion, a posteriori, of the modes of objective or real existence;^ and
the word was afterwards employed and applied in the same manner
by Plotinus,' and other of the older philosophers.
By Kant* again, and, in conformity to his ex-
ample, by many other recent philosophers, the
word has been usurped to denote the a priori cognitions, or fun-
damental forms of thought. Nor did Kant stop here ; and I may
explain to you the genealogy of another of his
/expressions, of which I see many of his German
disciples are unaware. By the Schoolmen,
whatever, as more general than the ten cate-
gories, could not be contained under them, was
said to rise beyond them — to transcend them ; and, accordingly,
such terras as being, one, ichole, good,' etc., were called transcendent
or transcendental {transcendentia or transcendentalia')? Kant, as
he had twisted the term category, twisted also these correlative
expressions from their original meaning. He did not even employ
the two terms transcendent and transcendental jxs correlative. The
Kant's employment
of the term.
Transcendent and
Transcen/ientai, — their
original employment
and use by Kant.
1 See Discussions, p. 140. — Ed.
2 See especially Metaph., iv. 7. In the trea-
tise specially devoted to them, the Cetepories
are viewed rather in a grammatical than iu a
metaphysical aspect. — Ed.
3 Enn. VI., 1. i., c. i. — Ed.
■4 Kritik.d. r. V., p. 78 (ed. Rosenkranz), Pro-
eegoinena, § 39. — Ed,
fi [Sec Facciolati, Rud., p. 39; and Inst., p.
26.] [Lo^ca, t. i., Rudimenta Logica, P. I., c.
iv., ( 7. " Aliud est categoricum, quod significat
ccrtam quamdam rem catcgoria comprchen-
8nm: aliud vagum, quod nulla categoria con-
tinetur, sed per omucs vagatur, cujusmodi
sunt essentia, bonitas, ordo, et similia multa."
Ldgica, t. ii., Institutiones Logicm, P. I., c. ii.
" Sunt qusedam vocabula, quae vaga et (ran-
jc^n(/en<iadicuntur: quod genus quodlibetex-
supcrent in omni categoria. Uujusmodi sunt
tns, aliquid, res, wnum, vertim, bonum." Cf.
Reid^s Works, p. 687 note §. — Ed.]
Excluded from the Aristotelic Categories,
all except the following:
Ex parte vocis — " Vox una et simplex, re-
bus concinna locandis."
K.v ]-arto rci — " Entia per scsc, finita, ri-alia,
tota."
See others in HurincUius, Isagoge, c. i. J
Sanderson, p. 20, [Murmellius gives as his
own the verses —
Complexum, Consignlficans, Fictum, Poly-
semum.
Vox logicse, Deus, Ezcedens, Priratio, Pars-
.que,
Haec, studiose, categoriis non accipiuntur.
And Sanderson [Logica, L. i. c. viii.), after
citing the mnemonic of the Categories them-
selves, adds, "In aliqua istarum classium
quicquid uspiam rerum est collocatur; mode
sit unum quid, reale, completum, limitatepgue ac
Jinita, natitrct. Exttlant ergo his sedibus In-
ttntiones Seeundae, Privationes, et Ficta, quia
non sunt realia; Concreta, Er/uivoca, et Com-
plexa, quia non sunt una; Pars, quia non est
completum quid; Deus, quia non est finite;
Tranacendens, quia non est limitatae natune.
Hinc versiculi :
Complexum, Consign iflcans, Privatio, Fic-
tum,
Pars, Deus, iE/quivocum, Transcendeos,
Ens rationis:
Sunt exclusa decern classibus Ista novem."'
— Ed.]
[That the Categories of Aristotle are not ap-
plicable to God, see (Pseudo) Augustin, D*
Cognition* Vera Vila, c. iii.]
Lkct. XL L-OGIC. 141
latter he applied as a synonym for a priori, to denote those elements
of thought which were native and necessary to the mind itself, and
which, though not manifested out of experience, were still not con-
tingently derived from it by an a posteriori process of generaliza-
tion. The term transcendeiit, on the contrary, he applied to all
pretended knowledge that transcended experience, and was not
given in an original principle of the mind. Transcendental he thus
applied in a fovorable, transcendeiit in a condemnatory accepta-
tion.^ But to return from this digression.
The Categories of Aristotle do not properly constitute a logical^
but a metaphysical, ti'eatise ; and they are, ac-
categories of Aris- pordingly, not Overlooked in the Aristotelic
totle Sletaphysical. ° •'
books on the First Philosophy, which have ob-
tained the name of Metaphysics {to. pxra ra (fiva-iKa). Their insertion
in the series of the surviving treatises of Aristotle on a logical
argument, is, therefore, an error.^
But, looking at these classes as the highest genera into which
simple being is divided, they are, I think, obnoxious to various ob-
jections. Without pausing to show that in other
Categories criticized j-gspects they are imperfect, it is manifest that
as a classification of , t-, .
Bgi^ the supreme genus or category Being is not
immediately divided into these ten classes, and
that they neither constitute coordinate nor distinct species. For
Being (to ov, ens^ is primarily divided into Being by itself (ens per
se), and Being by accideti.t (ens per accidens). Being by itself corre-
sponds to the first Category of Aristotle, equivalent to substance;
Being by accident comprehends the other nine, but is, I think, more
properly divided in the following manner : — Beitig by accident is
viewed either as absolute or as relative. As absolute, it flows either
from the matter, or from the form of things. If from the matter,
it is Quantity, Aristotle's second category ; if from the form, it is
Quality, Aristotle's third category. As relative, it corresponds to
Aristotle's fourth category. Relation ; and to Relation all the other
six may be reduced. For the category Where is the relation of a
thing to other things in space; the category When is the relation of
a thing to other things in time. Action and Passion constitute a
single relation, — the relation of the agent and the patient. Posture
is the relation of the parts of the body to each other; finally, Habit
1 Kriiih d. r. V., p. 240, edit. Rosenkranz. 3 With this classification of the Categories,
Ed. compare Aquina.'s, In Arist. MetapJi., h. v.
2 That the Categories of Aristotle are not lect. 9. Suarez, Dispuiationes Metaphysiae.
logical but metaphysical, see C. Carleton; Disp. 39, §§ 12, 15. — Ed.
rrhomas Compton Carleton, Philosophia, Uni-
versa, Disp. Met. d. vi. § 1. — Ed.]
142
LOGIC.
Lect. Xl
is the relation of a thing containing and a thing contained. The
little I have now said in regard to the categories of Aristotle is
more, perhaps, than I was strictly warranted to say, considering,
them, as I do, as wholly extralogical, and I have merely referred to
them as exhibiting an example of the application of the doctrine
of classification.^
I may, likewise, notice, by the way, that in the physical sciences of
arrangement^ the best instances of which are seen
in the different departments of Natural History,
it is found necessary, in order to mark the relative
place of each step in the ascending and descend-
ing series of classes, to bestow on it a particular
designation. Thus kingdom^ class, order, tribe^
family, genus, subgenus, species, subspecies, variety, and the like, are
terms that serve conveniently to mark out the various degrees of
generalization, in its application to the descriptive sciences of na-
ture. With such special applications and contingent differences,
Logic has, however, no concei-n. I therefore proceed to the last
relative denomination of concepts under the head of Subordination
in Extension. It is expressed in the following paragraph :
Names for the differ-
ent steps in the series
of classes in the physi-
cal sciences of ar-
rangement.
% XXXVII. A genus as containing under it species, or a
species as containing under it individuals, is
called a Logical, or Universal, or Sub)ect,
or Subjective, or Potential Whole ; while
species as contained under a genus, and in-
dividuals as contained under a species, are called Logical, or
Universal, or Subject, or Subjective, or Potential Parts. E con-
Par. XZZVn. Loari-
oal and Metaphysical
Wholes and Farts.
1 There is nothing in regard to which a
greater diversity of opinion lias prevailed,
even among Logicians, th.-iu the number of
Categories. For some alio w only two — Sub-
stance and Mode; others three — Substance,
Mode, and Relation ; others four — Mind,
Space, Matter, and Motion; others seven
which are comprehended in the following
distich :
" JW«n,t, yirmway Quits, Motus, Positura, Fig-
ura,
Crassaque Materies, dederunt exordia rebus."
Second line better —
" Sunt cum Materia, cunctarum exordia re-
rum."
AristotWs Logic, c. ii. H 1)2; Reiifs Account
of, Works, p. 6S5 ft sfq. See Facciolati, Logica,
t. i. Rudimenla Logica, V. I., c. iii. p. 32.
Purohot, Imtit. Philos., t. i. Logica, p. 82, ed.
1716. Cbauvin, Lexicon Philosopkieum, v. Cate-
gorema. [For various attempts at reduction
and classification of the categories, see IMoti-
nus, Ennend , VI. L. ii., c. 8 et seq. (Tenne-
mann, Gesch. der Phil., vi., p. 175 et ug.) Da-
vid the Armenian, in Brandis, Scholia ad
Arisiot., p. 49. Ramus, Animad. Aristot. [L.
iv., p. 80 et seq., ed. 1560, Ed.] Jo. Picua Mi-
randulanus. Conclusions, Opera, p. 90, ed.
Basil, 1572; Laurentius Valla, [Wa/uctiVo! Dis-
putationes, cc. i. ii. — Ed.] Eugenics, Aoyuci)
p. 125 et seq. On categoric tables of various
authors, see Denzinger, Jnst. Log , ii. ^ 606, p.
55. On history of categories in antiquity, sec
Petersen, Chrysippem Phil. Fundamenta, p. 1
et ftq. For the doctrines of the Platonists
and Stoics on the subject of the Categories,
see Facciolati, Inst. Log., [Logira t. ii., p. il ,
p. 84 et seq. Cf Trendelenburgh, OtsekichU
der KatfgoritnXehre, pp. 251, 267.— Ed.]
I
Lect. XI. LOGIC. 143
verso, — an individual as containing in it species, or a species as
containing in it genera, is called a Metaphysical or Formal or
Actual Whole ; while species as contained in an individual, and
genera as contained in species, are called Metaphysical, or For-
mal, or Actual Parts} This nomenclature, however, in so far as
metaphysical is opposed to logical, is inept ; for we shall see
that both those wholes and parts are equally logical, and that
logicians have been at fault in considering one of them, in their
doctrine of reasoning, to the exclusion of the other.
A whole is that which contain^ parts ; a part is that which is
contained in a whole. But as the relation of a
EbcpHcation. i , t • i • i t
whole and parts is a relation dependent on the
point of view from which the mind contemplates the objects of its
knowledge, and as there are different points of view in which these
may be considered, it follows that there may also be different wholes
and parts. Philosophers have, accordingly, made various enumera-
tions of wholes ; and, without perplexing you with any minute dis-
cussion of their various divisions, it may be proper, in order to
make you better aware of the two wholes with which Logic is con-
versant, — (and that there are two logical wholeg, and consequently,
two grand forms of reasoning, and not one alone, as all logicians
have hitherto taught, I shall hereafter endeavor
General view of ^^^ convince you), — to this end, I say, it may be
the various possible ,. . ■, • ^ ■,
Yf\io\ee, expedient to give you a general view oi the
various wholes into which the human mind may
group up the objects of its speculation.
Wholes may first be divided into two genera, — into a Whole
by itself {totum per se), and a Whole by acci-
Whoie eracciutn^^ dent {totuni per accidens). A Whole per se is
that which the parts of their proper nature
necessarily constitute ; thus body and soul constitute the man. A
Whole per accidens is that'which the parts make up contingently ;
as when man is considered as made up of the poor and the rich.
A Whole per se may, again, be subdivided into five kinds, into a
Logical, a Metaphysical, a Physical, a Mathe-
whoie per^e divided niatical, and a Collective. 1°, A Logical, styled
into, 1°, Logical; 2°, , ' . , ^ , . o , • • V.
Metaphysical. ^^^^ ^ Universal, a subject or Subjective, a Po-
tential Whole ; and, 2°, A Metaphysical, styled
also a Formal or an Actual Whole, — these I have defined in the j)ara-
1 See Timpler, iog-ica, [p. 232 er seq.\ Fac- ica Restituta, P. III., c. ii., § 2, ed. Generse,
siolati, [Logica, t. i., Rudimenta Logica, P. II., 16G8. — Ed.] Burgersdyk, [Institutionei Log-
c. vi., p. 51, 52. — Ed.] Derodon, p. 447 [Log- icm, p. 51 — Ed.]
144 LOGIC. Lect. XI.
graph. It is manifest that the logical and metaphysical wholes are
the converse of each otiier. For as the logical whole is the genus,
the logical parts the species and individual ; in the metaphysical,
e contra^ an individual is the whole of which the species, a species the
whole of which the genera, are the parts. A metaphysical whole is
thus manifestly the whole determined by the comprehension of a
concept, as a logical Avhole is that M'hole determined by its exten-
sion ; and if it can be shown that the whole of comprehension
affords the conditions of a process of reasoning equally valid,
equally useful, equally easy, and, to say the least of it, equally natu-
ral, as that afforded by the w4iole of the extension, it must be
allowed that it is equally well entitled to the name of a logicnl
whole, as the whole which has hitherto exclusively obtained that
denomination. 3°, A Physical, or, as it is like-
so, Physical. . „ , ^ ' . , *'__, , . , , . ,
Wise called, an Essential Whole, is that which
consists of matter and of form, in other words, of substance and of
.„ „ ^ ,. , accident, as its essential parts. 4°, A Mathe-
4°, Mathematical. ' . . *^ '
matical, called likewise a Quantitative, an In-
tegral, more properly an Integrate, Whole {totum integratutn), is
that which is composed of integral, or, more properly, of integrant
parts (partes integrantes). In tliis whole every«part lies out of every
other part, whereas, in a physical whole, the matter and form, the
substance and accident, permeate and modify each other. Thus, in
the integrate whole of a human body, the head, body, and limbs, its
integrant parts, are not contained in, but each lies
6°, Collective. °. \ , r„ . ^ „ . , , ,
out 01, each other, o , A Collective, styled also a
Whole of Aggregation, is that which has its material parts separate
and accidentally thrown together, as an army, a heap of stones, a
]ule o.f wheat, etc'
But to proceed now to an explanation of the terras in the para-
graph last dictated. Of these, none seem to require any exposition,
save the words subjective and potential^ as synonyms applied to a
Logical or Universal whole or parts.
The former of these, — the term subjective^ or more properly sub-
ject, as applied to the species as parts subjacent
The terms .ii/ft/^rt and ^^^ q,. lying under, a geiius, — to the individuals,
subjective as applied to ^ i • ^ ^ i • j
. . , as parts subjacent to, or lying under, a species,
p„,t8. is a clear and appro]^riate expression. But, as
applied to genus or species, considered as
wholes, the term subject is manifestly improper, and the term sub-
jective hardly defensible. In like manner, the term universal, as
1 See above, p. 143, note. — Ed.
^^v^r. XI. LOGIC. 145
applied to genus or species, considered as logical wholes, is correct ;
but as applied to individuals, considered as logical parts, it is used
in opposition to its proper meaning. The desire, however, to obtain
epithets common both to the parts and to the whole, and thus to
indicate at once the relation in general, has caused logicians to vio-
late the proprieties both of language and of thought. But as tljo
terms have been long established, I think it sufficient to put you on
your guard by this observation.
In regard to the term jyotential, — I shall, before saying anything,
read to you a passage from the Antient Meta-
The term poifnuai. physics of the learned Lord Monboddo.^ " In
J^rd Monboddo quo- ^, /> ^ i •. • • -ui i. ^t, x c
the nrst place, it is impossible, by the nature of
things, that the genus should contain the species
as a part of it, and the species should likewise contain the genus, in
the same respect. But, in different respects, it is possible that each
of them may contain the other, and be contained by it. We mnst,.
therefore, try to distinguish the different manners of containing, and
being contained. And there is a distinction that runs throusrh the
whole of ancient philosophy, solving many difficulties that are
otherwise unsurmountable, and which, I hope, Avill likewise solve
tliis difficulty. The distinction I mean is the distinction betwixt -
what exists 8waju,ei, or potentially only, and that which exists ti'cpyeio,.
or actually. In the first sense, everything exists in its causes; and,,
in the other sense, nothing exists but what is actually produced..
Now, in this first sense, the whole species exists in the genus ; for
the genus virtually contains the whole species, not only what actu-
ally exists of it, but what may exist of it in any future time. In
the same manner, the lowest species, below which there is nothing-
but individuals, contains virtually all those individuals, present and
future. Thus, the species man comprehends all the individuals now
existing, or that shall hereafter exist; Avhich, therefore, are said to*
be parts of the species man. On the other hand, the genus is actu-
ally contained in the species ; and the species, likewise, in each of
the individuals under it. Thus, the genus animal is actually con-
tained in the species m,an., without which it could not be conceived
to exist. And, for the same reason, the species man is actually con--
tained in each individual. It is a piece of justice which I think I
owe to an author, hardly known at all in the western parts of
Europe, to acknowledge that I got the hint of the solution of this;
difficulty from him. The author I mean is a living Greek author,
Eugenius Diaconus, at present Professor, as I am informed, in the
1 Vol. i. p. 479.
19
14G LOGIC. Lect. XL
Patriarch's University at Constantinople, who has written :in
excellent system of logic in very good Attic Greek."
This, or rather a similar passage at p. 73 of the fourth volume of
the Antient Metaphysics, affords Mr^ Stewart an
Stewart's strictures opportunity of making sundry unfavorable stric-
. ijp^gjj tures on the technical language of Logic, in
legard to which he asserts, " the adepts are not,
to this day, unanimously agreed ; " and adds, that " it is an extraor-
dinary circumstance, that a discovery on which, in Lord Monbod-
do's opinion, the whole truth of the syllogism depends, should be of
so very recent a date."^ Now this is another example which may
.serve to put you on your guard against any confidence in the asser-
tions and arguments even of learned men. You may be surprised
to hear, that so far is Eugenius from being the author of this ob-
servation, and of the term potential as applied to a logical whole,
that both are to be found, with few exceptions, in all the older sys-
tems of Logic. To quote only one, but one of the best and best
known, that of Burgei"sdyck, — he says, speaking of the logical
whole : " Et quia universale subjectas species et individua non actii
continet sed potentia ; factum est, ut hoc totum dictum sit totum po-
tentiale, cum ceterie species totius dicantur totum acttiale, quia partes
suas actu continent."^ Aristotle notices this difference of the two
wholes.'
Having thus terminated the consideration of concepts as recipro-
cally related in the perpendicular line of Subordination, and in the
quantity of Extension, in so far as they are viewed as containing
classes, — I must, before proceeding to consider them under thiH
quantity in the horizontal line of Coordination, state to you two
terms by which characters or concepts are denominated, in so far as
they are viewed as differences by which a concept is divided into
two subordinate parts.
% XXXVIIL The character, or complement of characters, by
which a lower genus or species is distin-
par.xxxviu. Gen- jruishcd, both from the genus to which it is
erio, Speeiflo. and In- ° . °
dividual Difference. Subordinate, and from the other genera or
species with which it is coordinated, is
called the Generic or the Specific Difference (8ta<^po yevurfi,
and 8ia<f>opa (iBiKrj, differentia generica, and differentia specijica).
The sum of characters, again, by which a singular or individual
1 EUmenti, vol. ii., c. iii., S 1; ITor*,*, vol. » Vide Timp'cr. LngUa, [L II. c. I. Dt 1>ut
Mi , p 199 and p. 200, note. ft Parte. — Ei>.]
2 Lib. I., c. xiv., p. 48, ed. 16G0. — Kd.
Lkct. XI. LOGIC. 147
thing is discriminated from the species under which it stands
and from other individual things along with which it stands,
is called the Individual or Singular or Numerical Difference
{differentia individualis vel singiUaris vel numerica)}
Two things are thus said to be generically different, inasmuch as
they lie apart in two different genera; specifi-
p ica ion. cally different, inasmuch as they lie apart in two
different species ; individually or numerically different, inasmuch as
they do not constitute one and the same I'eality. Thlis animal and
stone may be said to be generically different ; horse and ox to be
specifically different ; Highflyer and Eclipse to
Generic and Specific , • n • t 'j n j'/v. ^ t^ •
Difference "® numencally or mdividually ditterent. It is
evident, however, that as all genera and species,
except the highest of the one and the lowest of the other may be
styled indifferently either genera or species, generic difference and
specific difference are in general only various expressions of the same
thing; and, accordingly, the terms heterogeneous and homogeneous^
which apply properly only to the correlation of genera, are usually
applied equally to the correlation of species.
" Individual existences can only be perfectly discriminated in Per-
ception, external or internal, and their numerical
Individual or Sin- differences are endless ; for of all possible contra-
Ijular Difference. '■
dictory attributes the one or the other must, on
the principles of Contradiction and Excluded Middle, be considered
as belonging to each individual thing. On the other hand, species
and genera may be perfectly discriminated by one or few charac-
ters. For example, m.an^ is distinguished from eveiy genus or
species of animal by the one character of rationality; triangle^ from
every other class of mathematical figures, by the single character of
trilalerality. It is, therefore, far easier adequately to describe a
genus or species than an individual, existence ; as in the latter case,
we must select, out of the infinite multitude of characters which an
individual comprises, a few of the most prominent, or those by
which the thing may most easily be recognized."^ But as those
which we thus select are only a few, and are only selected with
reference to our faculty of apprehension and our capacity of mem-
ory, they always constitute only a petty, and often not the most
essential part of the numerical differences by which the individuality
of the object is determined.
Having now terminated the consideration of the Subordination of
1 Krng, Logfk, i 46. — Ed. a Krug, Log*, » 46, p. 184-6. — Ed.
LOGIC. Lect. XI.
concepts under Extension, it is only necessary to observe that their
Coordination under that quantity affords nothing which requires
explanation, except what is contained in the following paragraph :
% XXXIX. Notions, in so far as they are considered the
coordinate species of the same genus may
dS^tio^^^f concSu." ^6 ca"^ Conspecies ; and in so far ns Con-
species are considered to be different but
not contradictory, they aie properly called Discrete or Dis-
junct Nbtions (notionea discretes vel disjunctce). The term
Disparate {notiones disparatce) is frequently applied to this
opposition of notions, but less properly ; for this ought to be
reserved to denote the corresponding opposition of notions in
the quantity of Comprehension-
I conclude the consideration of concepts, as dependent on Exten-
«on, by a statement of the two general laws, by which both Sub-
ordination and Coordination of notions, under tliis quantity, are
regulated.
^ XL. The whole classification of things by Genera and
Species is governed by two laws. The one
p»r. XL. e two ^^ thcsc, the law of Honxoqaieitu (prluci-
general laws by which ' u j \x^
Subordination and Co- piuTH IIomogeneitatis\ is, — That how dif-
ordination.nnder Ex- fgrent socvcr may be any two concepts,
tension, are regtilat- J J J '
ed,-viE., of Homoge- they both Still Stand subordinated under
nS '°'* °'*"°*^" some higher concept; in other words, things
the most dissimilar must, in certain respects,
be similar. The other, the law of Heterogeneity (pn'/tcipivm
Ileterogeneitatis)^ is, — That every concept contains other con-
cepts under it ; and, therefore, when divided proximately, we
descend always to other concepts, but never to individuals; in
other words, things the most homogeneous — similar — must,
in certain respects, be heterogeneous — dissimilar.
Of these two laws, the former, as the principle which enables,
and in fact compels, us to rise from species to
Explication. genus, is that which determines the process of
Geiieriflcation and .„. ■,-,■, i...
speciflcation. Gcnerification ; and the latter, as the pnnciple
which enables, and in fact compels, us to find
always species under a genus, is that which regulates the process of
Specification. The second of these laws, it is evident, is only true
ideally, only true in theory. The infinite divisibility of concepts,
Lect. XL LOGIC. 149
like the infinite divisibility of space and time, exists only in specula-
tion. And that it is theoretically valid, will be
Law of Ueteroge- manifest, if we take two similar concepts, that
nei y rue on y in .^^ ^^^ concepts witli a Small difference : let us
then clearly represent to ourselves this difference,
and we shall find that how small soever it may be, we can always
conceive it still less, without being nothing, that is, we can divide it
ad infinitum; but as each of these infinitesimally diverging differ-
ences affords always the condition of new species, it is evident that
we can never end, that is, reach the individual, except per saltum}
There is another law, which Kant promulgates in the Critique
of Pure Meason' and which may be called the law of Logical
Affinity, or the law of Logical Continuity. It
aw o ogic - ig tiiig^ — That no two coordinate species touch
'^' so closely on each other, but that we can con-
ceive other or others intermediate. Thus man and orang-outang^
elephant and rhinoceros^ are proximate species, but still how great
is the difference between them, and how many species can we not
imagine to ourselves as possibly inteijacent?
This law I have, however, thrown out of account, as not univer-
sally true. For it breaks down when we apply
Grounds on which -^ j.^, mathematical classifications. Thus all an-
this law muBt be re- , . , , ... , _>
. . , gles are either acute or right or obtuse, hot
j€cted. '^ _ * _
between these three coordinate species or genera
no others can possibly be interjected, though we may always subdi'
vide each of these, in various manners, into a multitude of lower
sjjecies. This law is also not true when the coordinate species are
distinguished by contradictory attributes. There can in these be
no interjacent species, on the principle of Excluded Middle. For
example: — in the Cuvierian classification the genus animal is
divided into the two species of vertebrata and invertebrata, that is,
into animals with a backbone — with a spinal marrow ; and animals
without a backbone — without a spinal marrow. Is it possible to
conceive the possibility of any intermediate class ? '
I Cf. Krug, Logik, } 45 p. 135, and pp. 136, 3 Bachmann, [Logik, i 61, pp. 102, 103.—
137. — Ed. Ed.] [Compare Fries, Logik, § 21. — Ed.]
i P. 510. ed. Boeenkranz, C£ Kmg, Logik,
p. 138.— Ed.
LECTURE XII.
STOICHEIOLOGY.
SECTION II. — OF THE PRODUCTS OF THOUGHT.
L — ENNOEMATIC.
m. RECIPROCAL RELATIONS OF CONCEPTS.
B. QUANTITY OF COMPREHENSION.
Having now concluded the consideration of the Reciprocal Re-
lation of Concepts as determined by the quantity
Reciprocal Relation ^f Extension, I proceed to treat of that rela-
of notions in Compre- ^. i ^ j i ^i. ^ ^-^ i»
tion as regulated by the counter quantity of
beusion.
paragraph : —
Compreheiisiou. On this take the following
^ XLI. When two or more concepts are compared together
according to their Comprehension, they
Par. xLi. identi- either coincidc or they do not ; that is, they
cal and Different no- • i -i
tions. either do or do not comprise the same char-
acters. Notions are thus divided into Iden-
tical and Different {conceptus identici et diversi). The Iden-
tical are either absolutely or relatively the same. Of notions
Absolutely Identical there are actually none ; notions Relatively
Identical are called, likewise, Similar or Cognate {notiones
similes, afflnes, coynatw) ; and if the common attributes, by
which they are allied, be proximate and necessaiy, they are
called Reciprocating or Convertible {notiones reciprocce, con-
vertibiles)}
In explanation of this paragraph, it is only necessary to say a
word in regard to notions absolutely Identical. That such are
1 [Esser, Logik, S 86.]
Lect. Xn. LOGIC. 161
impossible, is manifest. " For, it being assumed that such exist,
as absolutely identical, they necessarily have no
Explication. differences by which they can be distinguished :
Absolutely Identical v , i . • -i- mi i. i -iL
... but what are indiscernible can be known, neither
notions impossible. '
as two concepts, nor as two identical concepts ;
because we are, ex hypothesis unable to discriminate the one from
the other. They are, therefore, to us as one. Notions absolutely
identical can only be admitted, if, abstracting our view altogether
from the concepts, we denominate those notions identical, which
have reference to one and the same object, and which are conceived
either by different minds, or by the same mind, but at different
times. Their difference is, therefore, one not intrinsic and neces-
sary, but only extrinsic and contingent. Taken in this sense, Abso-
lutely Identical notions will be only a less correct expression for
Heciprocating or Convertible notions." *
\ XLII. Considered under their Comprehension, concepts,
again, in relation to each other, are said to
.itiouo?cLep°r°" ^e either Congruent or Agreeing, inasmuch
as they may be connected in thought ; or
Conflictive, inasmuch as they cannot. > The confliction consti-
tutes the Opposition of notions (jo avriKelcrSaL, oppositio). This
is twofold ; — 1°, Immediate or Contradictory Opposition, called
likewise Repugnance (to dvTi<^aTtKois avriKv-d^ai, dvTi</)ao-is, opposi-
tio immediata sive contradictoria, repugnantia) ; and, 2°, Me-
diate or Contrary Opposition (to ei/aKTiws dvTUfcicr^ai, cvavnoTiys,
oppositio mediata A^el contraria). The former emerges when
one concept abolishes (tollit), directly or by simple negation,
what another establishes (jponit) ; the latter, when one concept
does this not directly or by simple negation, but through the
aflSrmation of something else.^
" Identity is not to be confounded with Agreement or Congru-
ence, nor Diversity with Confliction. All iden-
Expiication. tical Concepts are, indeed, congruent; but all
dentrty and Agree- congruent notions are not identical. Thus leam-
ment, Diversity and ,
Confliction. ^'^9 ^'^•^ Virtue, beauty and riches, magnanimity
and stature, are congruent notions, inasmuch as,
in thinking a thing, they can easily be combined in the notion we
form of it, although in themselves very different from each other.
1 [Esser, Logih, \ 36, p. 79.] Cf. Kmg, Logik, 2 Cf. Drobisch, Logik, p. 17, § 25 aeq.
i 37, and Anm. i. — Ed.
152 LOGIC. Lect. XII
In like manner, all conflictive notions are diverse or different notions,
for unless different, they could not be mutually conflictive ; but on
the other hand, all different concepts are not conflictive ; but those
only whose difference is so great that each involves the negation of
the other ; as, for example, virtue and vice, beauty and deformity,
wealth and poverty. Thus these notions are by preeminence, — kut
iio)(r]v, — said to be opposed, although it is true that, in thinking, we
can opposcj or place in antithesis, not only different, but even iden-
tical, concepts."
" To speak now of the distinction of Contradictory and Contrary
Opposition, or of Contradiction and Contrariety ;
Coutradictory and ^ ^i ^i /• /-i ^ j- ^•
„ ^ r, :■ — 01 these the former — Contradiction — is?
Contrary Oppositiou.
exemplified in the opposites, — yellow, not yeL
low, walking, not walking. Here each notion is directly, inimedis
ately, and absolutely, repugnant to the other, — they are reciprocal
negatives. This opposition is, therefore, properly called that of
Contradiction or of Repugnance / and the opposing notions them-
selves are contradictory or repugnant notions, in a single word, con-
tradictories. The latter, or Contrary Opposition, is exemplified in
the opposites, yellow, blue, red, etc., walking, standing, lying, etc."
"In the case of Contradictory Opposition, there are only two
conflictive attributes conceivable ; and of these one or other must
be predicated of the object thought. In the case of Contrary Oppo-
sition, on the other hand, more than two conflictive characters are
possible, and it is not, therefore, necessary, that if one of these be
not predicated of an object, any one other must. Thus, though I
cannot at once sit and stand, and .consequently sitting and standing
are attributes each severally incompatible with the other ; yet I may
exist neither sitting nor standing, — I may lie ; but I must either sit
or not sit, I must either stand or not stand, etc. Such, in general,
are the oppositions of Contradiction and Contrariety."
"It is now necessary to say a word in regard to their logical sig-
nificance. Immediate or Contr;idictory Oppo-
Logicai significance g-^j^j^ constitutes, in Logic, afiirmativc and neg-
of Contradictory and . . t\ i r- i • •
Contriiry Opposition. ^^^e notions. By the former somethmg is
posited or affinned (ponitur, affirmatur) ; by
the latter, something is sublated or denied {tollitur, negatur). This,
however, is only done potentially, in so far as concepts are viewed
apart from judgments, for actual aftirmation and actual negation
suppose an act of judgment ; but, at the same time, in so far as two
concepts afford the elements, and, if brought into relation, necessi-
tate the formation of an aflirmative or negative proposition, they
may be considered as in themselves negative and aflirmative."
Lect. Xn. LOGIC. 153
" Further, it is evident that a notion can only be logically denied
by a contradiction. For when we abstract from the matter of a
notion, as Logic does, it is impossible to know that one concept
excludes another, unless the one be supposed the negation of the
other. Logically considered, all positive or affirmative notions are
congruent, that is, they can, as far as their form is concerned, be all
conceived or thought together; but whether in reality they can
coexist — that cannot be decided by logical rules. If, therefore,
we would, with logical precision and certainty, oppose things, we
must oppose them not as contraries {A S 0), but as contradicto-
ries (A — not A JB — not B O — not C). Hence it also follows,
that there is no negation conceivable without the concomitant con-
ception of an affirmation ; for we cannot deny a thing to exist, with-
out having a notion of the existence which is denied." ^
There are also certain other relations subsisting between notions,
compared together in reference to their Comprehension.
% XLIII. Notions, as compared with each other in respect
of their Comprehension, are further distin-
Bion'otioDB ' ' guished into Intrinsic and Extrinsic. The
former are made up of those attributes
which are essential, and, consequently, necessary to the object
of the notion : these attributes, severally considered, are called
Essentials^ or Internal Denominations (oiauLSr], essentialia, de-
nominationes internee, intrinsicce), and, conjunctly, the Essence
(ova-Lo, essentia). The latter, on the contrary, consist of those
attributes which belong to the object of the notion only in a
contingent manner, or by possibility ; and which are, therefore,
styled Accidetits, or Extrinsic Denominations (a-vfiPe^rjKOTOy
accidentia, denomi?iationes externce or extrinsicce).^
So much for the mutual relations of notions in reference to their
Comprehension, when considered not in the relations of Involution
and Coordination.
Having thus given you the distinctions of no-
invoiution and Co- tions, as founded on their more general relations
ordination of Concepts ^^der the quantity of Comprehension, I now
under Comprehen- - • i i t i •
sion,— these wholly proceed to Consider them under this quantity
neglected by logicians. in their proximate relations; that is, in the rela-
tion of Involution and the relation of Coordi-
nation. These relations have been, I may say, altogether neglected
1 Krug, Log^, p. 118—120. —Ed. S Krug, Logik, J 39.— Ed.
20
164 LOGIC. Lect. xn
by logicians; and, in consequence of this, they have necessarily
overlooked one of the two great divisions of all
Hence reasoniDg in reasoning ; for all our reasoning is either from
comprehension over- i i i i i /. » i
looked by logicians. ^^^ ^hole to the parts and from the parts to the
whole, in the quantity of extension, or from the
whole to the parts and from the parts to the whole, in the quantity
of comprehension. In each quantity there is a deductive, and in
each quantity there is an inductive, inference ; and if the reasoning
under either of these two quantities were to be omitted, it ought,
perhaps, to have been the one which the logicians have exchisively
cultivated. For the quantity of extension is a creation of the mind
itself^ and only created through, as abstracted from, the quantity of
comprehension ; whereas the quantity of comprehension is at once
given in the very nature of things. The former quantity is thus
secondary and factitious, the latter primary and natural.
That logicians should have neglected the process of reasoning
which is competent betM'een the parts and whole
But probably con- ^f ^j^g quantity of Comprehension, is the more
. remarkable, as, after Aristotle, they have in gen-
eral articulately distinguished the two quantities
from each other, and, after Aristotle, many of them have explicitly
enounced the special law on which the logic of comprehension pro-
ceeds. This principle established, but not applied, is expressed in
the axiom — The character of the character is the character of the
thing; or, The predicate of the predicate is the predicate of the
subject {Nbta notce est nota rei ipsius ; PrcBclicatuni prcedicati est
pr(Bdicatum sulgecti). This axiom is enounced by Aristotle ; * and
its application, I have little doubt, was fully understood by him. In
fact, I think it even possible to show in detail that his whole analy-
sis of the syllogism has reference to both quantities, and that the
great abstruseness of his Prior Analytics, the treatise in which he
develops the general forms of reasoning, arises from this, — that he
has endeavored to rise to formulee sufficiently general to express at
once what was common to both kinds ; — an attempt so far beyond
the intelligence of subsequent logicians, that they have wholly mis-
understood and perverted his doctrine. They understand this doc-
trine, only as applied to the reasoning in extensive quantity; and in
relation to this kind of reasoning, they have certainly made palpa-
ble and easy what in Aristotle is abstract and difficult. But then
they did not observe that Aristotle's doctrine applies to two species,
of which they only consider one. It was certainly proper to briivg
1 aiter.,0. iii.— £d.
Lkct, Xn. LOGIC. 155
down the Aristotelic logic from its high abstraction, and to deliver
its rules in proximate application to each of the two several species
of reasoning. This would have been to fill up the picture of which
the Stagirite had given the sketch. But by viewing the analytic as
exclusively relative to the reasoning in extension, though they sim-
plified the one-half of syllogistic, they altogether abolished the
other. This mistake — this partial conception of the science — is
common to all logicians, ancient and modern ; for in so far as I am
aware, no one has observed, that of the quantities of comprehension
and extension, each affords a reasoning proper to itself; and no one
has noticed that the doctrine of Aristotle has reference indifferently
to both ; although some, I know, having perceived in general that
we do reason under the quantity of comprehension, have on that
founded an objection to all reasoning under the quantity of exten-
sion, that is, to the whole science of Logic as at present constituted.
I have, in some degree, at present spoken of matters which properly
find their development in the sequel ; and I have made this antici-
pation, in order that you should attend particularly to the relation
of concepts, under the quantity of comprehension, as containing
and contained, inasmuch as this affords the foundation of one, and
that not the least important, of the two great branches, into which
all reasoning is divided.
1 XLIV. We have seen that of the two quantities of no-
tions each affords a logical Whole and
Par. XLIV. invo- Parts 1 and that, by opposite errors, the one
lution and Coordlna- n ■, i i . , .
tion. o* these has, through over inclusion, been
called the logical; whilst the other has,
through over exclusion, been called the metaphysical. Thus,
in respect of their Comprehension, no less than of their Exten-
sion, notions stand to each other in a relation of Containing
and Contained ; and this relation, which, in the one quantity
(extension) is styled that of /Subordination^ may in the other
(comprehension), for distinction's sake, be styled that of Invo-
lution. Coordination is a term which may be applied in either
quantity.^
In the quantity of comprehension, one notion is involved in
another, when it forms a part of the sum total of characters,
which together constitute the comprehension of that other;
and two notions are in this quantity coordinated, when, whilst
neither comprehends the other, both are immediately compre-
hended in the same lower concept.
1 [Cf. Drobiscb, Logik, n 22, 23. Fischer, Logii, f 49.]
166 LOGIC. Lbct. XIL
From what has been formerly stated, you are aware that the
quantity of comprehension, belonginar to a no-
Explication. ^ . "^ , \ ' * ^ , . , .
tion, IS the complement oi characters which it
contains in it ; and that this quantify is at its maximum in an indi-
vidual. Thus the notion of the individual Socrates, contains in it,
besides a multitude of others, the characters of /Son of Sophronis-
cus, Athenian, Greek, European, man, animal, organized being, etc.
But these notions, these characters, are not all equally proximate
and immediate ; some are only given in and through othei*s. Thus
the character Atfienian is applicable to Socrates only in and through
that of Son of Sophroniscus, — the character of Greek, only in
and through that of Athenian, — the character of JEuropean, only
in and through that of Greek, — and so forth ; in other words, Soc-
rates is an Athenian only as the son of Sophroniscus, only a Greek
as an Athenian, only a European as a Greek, only a man as a Euro-
pean, only an animal as a man, only an organized being as an ani-
mal. Those characters, therefore, that are given in and through
othei-s, stand to these others in the relation of parts to wholes ; and
it is only on the principle — Part of the part is a part of the whole,
that the remoter parts are the parts of the primary whole. Thus,
if we know that the individual Socrates comprehends the character
son of Sophroniscus, and that the character son of Sophroniscus
comprehends the character Athenian/ we are then warranted in
saying that Socrates comprehends Athe7iian, in other words, that
Socrates is an Athenian. The example here taken is too simple to
show in what manner our notions are originally evolved out of the
more complex into the more simple, and that the progress of science
is nothing more than a progressive unfolding into distinct conscious-
ness of the various elements comprehended in the characters, origi-
nally known to us in their vague or confused totality.
It is a famous question among philosophers, — Whether our
knowledge commences with the general or with
Controversy regard- ^^^ individual, — whether children first employ
ing the Pnmum Cogni- . , -r , .
^^^ common, or nrst employ proper, names. In this
controversy, the reasoners have severally proved
the opposite opinion to be untenable ; but the question is at once
solved by showing that a third opinion is the true, — viz., that our
knowledge commences with the confused and complex, which, as
regarded in one point of view or in another, may easily be mistaken
either for the individual, or for the general. The discussion of this
problem belongs, however, to Psychology, not to Logic' It is suffi-
cient to say in general, that all objects are presented to «s in
1 Sae Lutura tm MMtapkt/tit*, 1. zzzrL, p. 498 mq. — El>.
Lect. Xn. LOGIC. 157
complexity; that we are at first more struck with the points of
resemblance than with the points of contrast ; that the earliest no-
tions, and, consequently, the earliest terms, are those that corre-
spond to this synthesis, while the notions and the terms arising
from an analysis of this synthesis into its parts, are of a subsequent
formation. But though it be foreign to the province of Logic to
develop the history of this procedure; yet, as this procedure is
natural to the human mind. Logic must contain the form by which
it is regulated. It must not only enable us to reason from the sim-
ple and general to the complex and individual ; it must, likewise,
enable us to reverse the process, and to reason from the complex
and individual to the simple and the general. And this it does by
that relation of notions as containing and contained, given in the
quantity of comprehension. The nature of this reasoning can
. indeed only be shown, when we come to treat
In Comprehension, of syllogism ; at present, I only request that
the involving notion y^^ ^jn t,ejjr in mind the relations of Involu-
18 the more complex ; . ~i /-~i .. -i- • • t • ^ • i
the involved, the more t^^" ^^^ Coordmation, m which notions stand
simple. to each other in the whole or quantity of com-
prehension. In this quantity the involving no-
tion or whole is the more complex notion ; the involved notion or
part is the more simple. Thus pigeon as comprehending bird,
bird as comprehending Jeathered, feathered as comprehending t^jarw-
blooded, warm-blooded as comprehending heart with four cavities^
heart with four cavities as comprehending breathinff with lungs, are
severally to each other as notions involving and involved. Again,
notions, in the whole of comprehension, are coordinated when they
stand together as constituting parts of the no-
CoHrdination in Com- .• • i- r >.t. u ii. • t ^ i
^ . tion in which they are both immediately com-
prehension. •' •'
prehended. Thus the characters oviparous and
warm-blooded, heart with four cavities, and breathing by lungs, as
all immediately contributing to make up the comprehension of the
notion bird, are, in this respect, severally considered as its coordi-
nate parts. These characters are not relative and correlative — not
containing and contained. For we have oviparous animals which
are not warm-blooded, and warm-blooded animals which are not
oviparous. Again, it is true, I believe, that all warm-blooded ani-
mals have hearts with four cavities (two auricles and two ventricles),
and that all animals with such hearts breathe by lungs and not by
gills. But then, in this case, we have no right to suppose that the
first of these characters comprehends the second, and that the sec-
ond comprehends the third. For we should be equally entitled to
assert, that all animals breathing by lungs possessed hearts of four
168 LOGIC. Lkct. xn.
cavities, and that all animals with such hearts are warm-blooded.
They are thus thought as mutually the conditions of each other ;
and whilst we may not know their reciprocal dependence, they aae,
however, conceived by us, as on an equal footing of coordination.
(This at least is true of the two attributes heart with four cavities
and breathing by lungs; for these must be viewed as coordinate ;
but, taken together, they may be viewed as jointly necessitating
the attribute of warm-blooded^ and, therefore, may be viewed as
comprehending it.) On this I give you the following paragraph.
^ XLV. Notions coordinated in the whole of comprehen-
sion, are, in respect of the discriminating
Par. XLV. coordi- charactei*s, different without any similarity.
nation of notious In , ,
Comprehension. They are thus, pro tanta, absolutely differ-
ent ; and, accordingly, in propriety are called
Disparate Notions (notiones disparatoi). On the other hand,
notions coordinated in the quantity or whole of extension, are,
in reference to the objects by them discriminated, different (or
diverse) ; but, as we have seen, they have always a common
attribute or attributes in which they are alike. Thus they are
only relatively different (or diverse) ; and, in logical language,
are properly called Disjunct or Discrete Notions {notiones^ dis-
junctcB^ discretes)}
I [Drobisoh, Logik, H 28, 2L Cf. Fiaeher, Logik, f 49 tt Mf.]
LECTURE XIII.
STOICHEIOLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT.
II. — APOPHANTIC, OR THE DOCTRINE OF JUDGMENTS.
JUDGMENTS. — THEIR NATURE AND DIVISIONS.
Having terminated the Doctrine of Concepts, we now proceed
to the Doctrine of Judgments. Concepts and Judgments, as I
originally stated, are not to be viewed as the
octrine o u g- results of different operations, for every concept,
as the product of some preceding act of Com-
parison, is in fact a judgment fixed and ratified in a sign. But in
consequence of this acquired permanence, concepts afford the great
means for all subsequent comparisons and judgments, and as this
now forms their principal relation, it behoved, for convenience,
throwing out of view their original genealogy, to consider Notions
as the first product of the Understanding, and as the conditions or
elements of the second. A concept may be viewed as an implicit
or undeveloped judgment; a judgment as an explicit or developed
concept. But we must now descend to articulate statements.
*ir XL VI. To Judge (xpivctv,^ judicare) is to recognize the
relation of congruence or of confliction, in
ment.-wiiat. which two couccpts, two individual things,
or a concept and an individual, compared
together, stand to each other. This recognition, considered as
an internal consciousness, is called a Judgment (Xoyos aTro<f>avTi-
K6<i, Judicium) ; considered as expressed in language, it is called
a Proposition or Predication (d7ro'<^ai/Tis, irporaa-i^,^ Staomy/Ao,
1 The verb Kpiveiv, to judge, and still more 2 [Aristotle uses the term irpSraffis merely
the substantive, Kplffn, judgment, are rarely for the premise of a syllogism, especially the
used by the Greeks — (never by Aristotle) — major (he has no other word for premise);
as technical terms of Logic or Psychology. whereas aird^ou^is he employs always for aa
160 LOGIC. Lect. xm.
propositio, prcedicatio, pronunciatum, enunciation effatum, pro-
faturn^ axioTnd)}
As a judgment supposes a relation, it necessarily implies a plural-
ity of thoughts, but conversely a plurality of
Explication,— what thoughts does not necessarily imply a judgment,
men"^ '* *" " ^ The thoughts whose succession is determined
by the mere laws of Association, are, though
manifested in plurality, in relation, and, consequently, in connection,
not, however, so related and so connected as to constitute a judg-
ment. The thoughts water, iron, and rusting, may follow each
other in the mental train ; they may even be viewed together in a
sinmltaneous act of consciousness, and this without our considering
them in an act of Comparison, and without, therefore, conjoining
or disjoining them in an act of judgment. But when two or more
thoughts are given in consciousness, there is in general an endeavor
on our part to discover in them, and to develop a relation of con-
gruence or of confliction ; that is, we endeavor to find out whethei*
these thoughts will or will not coincide — may or may not be
blended into one. If they coincide, we judge, we enounce, their
congiuence or compatibility; if they do not coincide, we judge, we
enounce, their confliction or incompatibility. Thus, if we compare
tlie thoughts — wafer, iron, and rusting, — find them congru,ent,
.•md connect them into a single thought, thus — water rusts iron, —
in that case we form a Judgment.^
But if two notions be judged congruent, in other words, be con-
ceived as one, this their unity can only be real-
CondiUon under j^ed in consciousncss, inasmuch as one of these
wliicli notions arc con- . . . , ^^ -i ^ j ^ •
, . _. ^ notions IS viewed as an attribute or aetermma-
fiiaered congruent.
tion of the other. For, on the one haad, it is
impossible for us to think as one two attributes, that is, two things
viewed as determining, and yet neither determining or qualifying
the other ; nor, on the other hand, two subjects, that is, two things
thought as determined, and yet neither of them determined or qual-
ified by the other. For example, we cannot think the two attri-
butes electrical and polar as a single notion, unless we convert the
one of these attributes into a subject to be determined or qualified by
the other : but if we do, — if we say, what is electrical is polar, we
at once reduce the duality to unity, — we judge XhdX polar is one of
enunciation considered not as merely syllo- I. p. 868. Organon Aict't, i^. 92, 127, 240 « se^^
gistic. See Ammonium, In De Interpret., f. 4 a. 416, 417.]
Ur. p. 4. Lat. Facc\o\a.i\^Rudimenta Logica, F. 1 By Stoics and Ramists.
il. c. i. p. 59. Waitz, Commentariua in Organon, 2 Cf. Kmg, Logik, { 61. Anm. i. p. 149, 160.
lect. xm. LOGIC. 161
the constituent characters of the notion electrical^ or that what is
electrical is contained under the class of things marked out by the
common character of polarity. In like manner, we cannot think
the two subjects iron and mineral as a single notion, unless we con-
vert the one of the subjects into an attribute by which the other is
determined or qualified ; but if we do, — if we say, iron is a min-
eral, we again reduce the duality to unity ; we judge that one of the
attributes of the subject iron is, that it is a mineral, or that iron is
contained under the class of things marked out by the common
character of mineral.
From what has now been said, it is evident that a judgment
must contain and express three notions, which,
' J" ^™^" ™"* however, as mutually relative, constitute an indi-
contain three notions. ' •' '
visible act of thought. It must contain, 1°, The
notion of something to be c^etermined; 2°, The notion of some-
thing by which another is determined; and, 3°, A notion of the
relation of determination between the two. This will prepare you
to understand the following paragraph.
\ XL VII. That which, in the act of Judging, we think as
the determined or qualified notion, is tech-
par. xLvn. Sub- nically called the Subject (vTrofcci/xevov, sv^-
cop'uia. ' jectum) ; that which we think as the deter- -
mining or qualifying notion, the Predicate
(Karriyopovfifvov, prcBdicatum) ; and the relation of determina-
tion, recognized as subsisting between the subject and the pred-
icate, is called the Copula. By Aristotle, the predicate includes
the copula ; ^ and, from a hint by him, the latter has, by subse-
quent Greek logicians, been styled the Appredicate (Trpoa-KaTr]-
yopovixevov, apprcedicatum).^ The Subject and Predicate of a
proposition are, after Aristotle, together called its Terms or
JEkctr ernes ^ (opot a.Kpa irepara, termini) ; as a proposition is by
him sometimes called an Interval (SLdaTrjfjia)* being, as it were,
a line stretched out between the extremes or terms. We may,
therefore, articulately define a judgment or proposition to be
the product of that act in which we pronounce, that, of twO'
1 See De Interp., c. 3, where the pvfia, or to denote the predicate of a proposition, see
verb, includes the predicate and copula Ammonius, on De Interp., p. 110, b. ed. Aid.
united. —Ed. Venet, 1546. See below, p. 162. — Ed. [For
2 See De Interjjretatione, c. 10, § 4. "OTav the origin of this distinction see Blemmidag ;
8e rb tim tpiTov trpvffKaTiyyoprirai, an (after Aristotle), Lo°-iea, p. 186.]
expression to which may be traced the scho- 3 AnaX. Prior., 1. 1, 4. — Ed.
lastic distinction between seeundi and tertii ad- ^ Anal. Prior. 1. 15 16 25. El>.
iacentis. For the term irpoaKKTifyopovnevov
21 t
162 LOGIC. lect. xm.
notions thought as subject and as predicate, the one does or
does not constitute a part- of the other, either in the quantity
of Extension, or in the quantity of Comprehension.
Thus in the proposition, iron is magnetic, we have iron for the
Subject, magnetic for the Predicate, and the
Illustration. . ■i/.i>~,-,t
substantive verb is for the Copula. In regard to
this last, it is necessary to say a few words. " It is not always the
case, that in propositions the copula is expressed by the substantive
verb is or est, and that the copula and predicate stand as distinct
words. In adjective verbs the copula and predicate coalesce, as in
the proposition, the sun shines, sol lucet, which is equivalent to the
stcn is shining, sol est lucens. In existential propositions, that is,
those in which mere existence is predicated, the same holds good.
For when I say I am,, Ego sum, the am or sum has here a far
higher and more emphatic import than that of the mere copula or
link of connection. For it expresses, lam existing, Ego sum, exist-
ens. It might seem that, in negative propositions, when the copula
is affected by the negative particle, it is converted into a non-
copula. But if we take the word copula in a wider meaning, for
that through which the subject and predicate are connected in a
mutual relation, it will apply not only to affirmative but to negative,
not only to categorical but to hypothetical and disjunctive, proposi-
tions."^ I may notice that propositions with the subject, predicate,
and copula, all three articulately expressed, have
Third^jacent" been Called by the schoolmen those of the third
adjacent {propositiones tertii adjacentis, or tertii
adjecti), inasmuch as they manifestly contain three parts. This is
a barbarous expression for what the Greeks, after Aristotle, called
Trporacrcis (k rpiTov {l(m\ Kartffopovfi.i.vov. For the same reason, prop-
ositions with the copula and predicate in one, were called those
of the second adjacent?
" What has now been said will enable you to perceive how far
concepts and judgments coincide, and how far
Concepts and judg- ^|^g differ. On the one hand, they coincide in the
mentEi, — how far they /» i , • x i r> ^ i
coincide and differ. followmg respccts : In the first place, the concept
and the judgment are both products ; the one the
product of a remote, the other the product of an immediate, act of
comparison. In the second place, in both, an object is determined
by a character or attribute. Finally, in the third place, in both,
1 Knig, Logik, | GS; Anni., ii., pp. I6S-4.— Schnize, Logik, p. 74; Crakaothovpa, l^mfit^
— Ed. [Compare Baobmann, Logik, p. 127; pp. 160, 167.)
! Sec above, p. 161, note % — E».
l^f£^T. XIIL LOGIC. 163
things relatively different in existence are reduced to a relative
identity in the unity of thought. On the other hand, they differ in
the following respects : In the first place, the determination of an
object by an attribute is far more express in the judgment
than in the concept ; for in the one it is developed, in the other,
only implied. In the second place, in the concept the unity of
thought is founded only on a similarity of quality; in the judgment,
on the other hand, it is founded on a similarity of relation. For in
the notion, an object and its characters can only be conceived as
one, inasmuch as they are congruent and not conflictive, for thus
only can they be united into one total concept. But, in the judg-
ment, as a subject and predicate are not necessarily thought under a
similarity of quality, the judgment can comprehend not only con-
gruent, but likewise conflictive, and even contradictory, notions ; for
two concepts which are compared together can be I'ecognized as
standing in the relation either of congruence or of repugnance.
Such is the sameness, and such is the diversity, of concept and
judgment."'
We have thus seen that a judgment or proposition consists of
three parts or correlative notions, — the notion of a subject, the
notion of a predicate, and the notion of the mutual relation of these
as determined and determining.
Judgments may, I think, be primarily divided in two ways, — the
divisions being determined by the general .dc-
d- d"/"^" **'"" °^ pendencies in which their component parts stand.
to each other, — and the classes afforded by
these divisions, when again considered, without distinction, in the
different points of view given by Quantity, Quality, and Relation,
will exhaust all the possible forms in which judgments are manifested
% XL VIII. The first great distinction of Judgments is taken
from the relation of Subject and Predicate,
Par. xLvm. First as rcciprocally whole and part. If the Sub-
mlntl!- comprehen- j^ct or determined notion be viewed as the
Bive and Extensive. Containing wholc, WO havo an Intensive or
Comprehensive proposition ; if the Predicate
or determining notion be viewed as the containing whole, we
have an Extensive proposition.
This distinction of propositions is founded on the distinction of
the two quantities of concepts, — their Comprehension and their
1 i^ser, I-ogUe, i 66, p. Ul.
164 LOGIC. Lect. XftL
Extension. The relation of subject and predicate is contained
within that of whole and part, for we can always
Explication, — this view either the determining or the determined
distinction founded notion as the whole which contains the other.
on tlie Comprehension -1,1 -i • i 1 i •
and Extension of Con- The wholc, howcvcr, which the subject consti-
cepts. tutes, and the whole which the predicate consti-
tutes, are different, — being severally determined
by the opposite quantities of comprehension and of extension ; and
as subject and predicate necessarily stand to each other in the re-
lation of these inveree quantities, it is manifestly a matter of in-
difference, in so far as the meaning is concerned, whether we view
the subject as the whole of comprehension, which contains the pre-
dicate, or the predicate as the whole of extension, which contains
the subject. In point of fact, in single propositions it is rarely ap-
parent whTch of the two wholes is meant ; for the copula is, est,
etc., equally denotes the one form of the relation as the other.
Thus, in the proposition man is two-legged, — the copula here is
convertible with comprehends or contains in it, for the proposition
means, man contains in it two legged; that is, the subject man, as an
. intensive whole or complex notion, comprehends as a part the
. predicate two-legged. Again, in the proposition m,an is a biped, the
copula corresponds to contained under, for this proposition is tanta-
mount to m,an is contained under biped, — that is, the predicate
biped, as an extensive whole or class, contains under it as a part the
subject m,an.. But, in point of fact, neither of the two propositions
unambiguously shows whether it is to be viewed as of an intensive
or of an extensive purport ; nor in a single proposition is this of any
moment. All that can be said is, that the one form of expression
is better accommodated to express the one kind of proposition^ tlie
other better accommodated to express the other. It is only when
propositions are connected into syllogism, that it becomes evident
whether the subject or the predicate be the whole in or under
which the other is contained; and it is only as thus constituting
two different, two contrasted, forms of reasoning, — forms the most
general, as under each of these every other is included, — that the
distinction becomes necessary in regard to concepts and proposi-
tions. The distinction of propositions into Extensive and Inten-
sive, it is needless to say, is, therefore, likewise the most general;
.•uid, accordingly, it is only in subordination to this distinction that
the other distinctions, of which we are about to treat, are valid.
I now proceed to the second division of Judgments, and com-
mence with the following paragraph :
lect. xni.
LOGIC. 166
% XLIX. The second division of Judgments is founded on
the different mode in which the relation of
Par. XLIX. Second determination may subsist between the sub-
division of Judg- •'
ments, - Categorical ject and predicate of a proposition. This
and Conditional. -the ^^^^i^^^ jg either Simple or Conditional
latter of whicli is sub- ■>■
divided into Hypo- (^propositio simplcx^ pTopositio condiUorir
theticai. Disjunctive, ^^..^ q^ ^^^ formcr alternative, the prop-
and Dilemmatic. ' ' t. i.
osition is called Categorical;^ on the latter,
inasmuch as the condition lies either in the subject or in the
predicate, or in both the subject and predicate, there are three
species of proposition. In the first case, the proposition is
Hypothetical, in the second, Disjunctive, in the thii-d Dilem-
matic or Hypothetico-disjunctive?
I shall consider these in their order ; and, first, of Categorical
propositions. But here it is proper, before pro-
ExpHcation,!. Cate- cccding to cxpound what is designated by the
eorical Judgments. , . . t ^ -^i i
The term tatcorkax term cotegorxcal, to commence with an explana-
tion of the term itself This word, as far as now-
known, was first employed by Aristotle in a logical signification. I
have already explained the meaning of the term category; ^ but you
are not to suppose that categorical has any reference to the ten
summa genera of the Stagirite. By Aristotle the term Ka-njyopiKos
is frequently employed, more especially in the books of the J^riot
Analytics, — and in these books alone it occurs, if I am correct in
my estimate, eighty-seven times. Now you will
it« signification as observe, that in no single instance is this word
used by Aristotle. 7- -i i » • i
applied by Aristotle, except m one unambiguous'
signification, that is, the signification of affirmative ; and it is thus
by him used as a term convertible with Kara^artKo?, and as opposed
to the two synonyms of negation he indifferently employs, — airof^a-
TLKo<i and oT-epr/TtKos.* Such is the meaning of the
Its meaning in the ^r^^^.^ jn Avistotelic usage. Now you will oh-
writings of his disci- . , . , . , n TrC.
ipg serve, that it obtained a totally difierent mean-
ing in the writings of his disciples. This new
meaning it probably obtained from Theophrastus, the immediate
disciple of Aristotle, for by him and Eudemus we know that it was
so employed; — and in this new meaning it was exclusively applied
1 [Categorical had better be called Absolute, 2 Cf. Krug, Logik, § 57. — Ed. [MoceniCHS.
Es is done by Gassendi, Logica, p. 287, ed. /oc. rit. ; Schulze, X-og-i A;, §§ 45, 52, 60— 69.]
Oxen; or Perfect, as by Mocenicus, who has 3 See above, p. 139. —Ed.
al> o Absolute. See Contemplaiiones PeripateticeB, 4 Compare Discussions, p. 152. — Ed.
ii c. 2, p. Sdetseg.^
166 1.0 G I c. Lbgt. xni
by -all the Greek and Latin expositors of the Peripatetic philosophy,
in fact, by all subsequent logicians without exception. In this
second signification, the terra categorical^ as applied to a proposi-
tion, denotes a judgment in which the predicate is simply affirmed
or denied of the subject, and in contradistinction to those proposi-
tions which have been called hypothetical and disjunctive. In this
change of signification there is nothing very re-
This difference of marlcable. But it b a singular circumstance
signification not hith- , t i i * • t i /> i
erto obeerred. that, though the Anstotelio employment oi the
word be in every instance altogether clear and un-
ambiguous, no one, either in ancient or in modern times, should ever
have made the observation, that the word was used in two different
meanings ; and that in the one meaning it was used exclusively by
Aristotle, and in the other exclusively by all other logicians. I find,
indeed, that the Greek commentators on the Organon do, in refer-
ence to particular passages, sometimes state, that Karriyopuccyi is there
used by Aristotle in the signification of affirmative ; but, in so far
as I have been able to ascertain, no one has made the general ob-
servation, that the word was never applied by Aristotle in the sense
in which alone it was understood by all other logical writers. So
much for the meaning of the term categorical ; as now employed
for simple or absolute, and as opposed to conditional^ it is used in a
sense difierent from its original and Aristotelic meaning.
In regard to the nature of a Categorical Judgment itself, it is
necessary to say almost nothing. For, as this
Nature of a Categor- ju^jorment is that in M'hich the two terms stand
ioalJudgment. , , . , . , , . , . .
to each other simply m that relation which
every judgment implies, to the exclusion of all extrinsic conditions,
it is evident, that what we have already said of the essential nature
of judgment in general, affords all that can be said of categorical
judgments in particular. A categorical proposition is expressed in
the following fornuil:e — A is B, or, A is not B. I proceed, iherfforo,
to the genus of propositions as opposed to categorical, — viz., tlio
Conditional, — Conditioned. This genus, as stated in the pnra-
graph, comprises two species, according as the
II. — Conditional condition lies more proximately in the subject.
Judgments. These ., .. ,.,. , tt-i
.i.^»i,«^..^i^ or in the predicate, to which is to be added,
eomprise three species. r ^ '
either as a third species or as a compound of
these two, those propositions in which there is a twofold condition,
the one belonging to tlie subject, the other to the predicate. The
first of these, as stuted, forms the class Hypothetical, the second
that of Disjunctive, the third that of Dileramatic, propositions. I
may notice, by the way, that there is a good deal of variation in
LBCT.Xm. LOGIC. 167
the language of logicians in regard to the terms Conditional and
Hypothetical. You are aware that conditionalis^
Variations in regard jn Latin, is commonly applied as a translation of
,0 the application of ^^^^^^^^ i„ Q,^.^^\^. and bv Boethius, who was
the terms Conautonat ' .
&nd Hypothetical. t^e first amoug the Latins who elaborated the
logical doctrine of hypotheticals, the two terms
are used convertibly with each other.' By many of the Schoolmen,
liowever, the terra hypothetical {hypotheticus) was used to denote
the genus, and the term conditional., to denote the species, and from
them this nomenclature has passed into many of the more modern
conipends of logic, — and, among others, into those of Aldrich and
Whately. This latter usage is wrong. If either term is to be used
in subordination to the other, conditional, as the more extensive
term, ouglit to be applied to designate the genus ; and so it has ac-
cordingly been employed by the best logicians. But to pass from
words to things.
I said that Hypothetical propositions are those in which the con-
dition qualifying the relation between the sub-
I. Hypothetical. . ? /• ,. • , • ,
ject and predicate lies proximately in the subject.
In the proposition, B is A, the subject B is unconditionally thought
to exist, and it thus constitutes a categorical proposition. But if
we think the subject B existing only conditionally, and under this
conditional existence enunciate the judgment, we shall have the
hypothetical proposition — -(/^ B is, A is, — or, in a concrete exam-
ple — Rainy weather is wet weather, is a categorical proposition, —
If it rains, it will be wet, is a hypothetical. In a hypothetical prop-
osition the objects thought stand in such a mutual relation, that
the one can only be thought in so far as the other is thought ; in
other words, if we think the one, we must necessarily think the
other. They thus stand in the relation of Reason and Consequent.
For a reason is that which, being affirmed, necessarily entails the
affirmation of something else ; a consequent is that which is only
affirmed, inasmuch as something previous is affirmed. The relation
between reason and consequent is necessary. For a reason followed
by nothing, would not be the reason of anything, and a consequent
which did not proceed from a reason, would not be the consequent
of anything. An hypothetical proposition must, therefore, contain
a reason and its consequent, and it thus presents the appearance of
two members or clauses. The first clause —that which contains
the reason — is called the Antecedent, also the Jieaso?i, the Condi-
1 Compare Diseustions, p. 160. For Boethius, see his treatise De SyUogismo Hypothetieo, It
L— Ed.
168 XOGIC. Lbct. Xffl.
tion, or the Hypothesis {hypothesis, conditio, ratio, antecedeiis,- —
i. e., memhrum siv e propositio) ; the second, which contains the con-
sequent necessitated by this ground, is called the Conseq^ient, also
the Thesis (consequens, thesis, rationatum, conditionatum). The
relation between the two clauses is called the Consequence [couse-
quentia), and is expressed by the particles if on the one hand, and
then, so, therefore, etc., on the other, which are, therefore, called the
Consecutive particles {particidoe consecutive)} These are frequently,
however, not fonnally expressed.
" This consequence (if is — then is) is the copula in hypothetical
jiropositions ; for through it the concepts are
ment not composite. brought together, 80 as to make up, in conscious-
ness, but a single act of thought ; consequently,
in it lies that synthesis, that connection, which constitutes the hypo-
thetical judgment. Although, therefore, a hypothetical judgment
appear double, and may be cut into two different judgments, it is
nevertheless not a composite judgment. For it is realized through
a simple act of thought, in which if and then, the antecedent and
the consequent, are thought at once and as inseparable. The prop-
osition, if B is, then A is, is tantamount to the proposition, A is
ihrovgh B. But this is as simple an act as if we categorically
judged B is A, that is, B is under A. Of these two, neither the
one — If the sun shines, nor the other — then it is day — if thought
apart from the othei', will constitute a judgment, but only the two in
conjunction. But if we think — The sun shines, and it is day,
each by itself, then the whole connection between the two thoughts
is abolished, and we have nothing more than two isolated categori-
cal judgments. The relatives if and then, in which the logical syn-
thesis lies, constitute thus an act one luid indivisible."
"For the same reason, a Hypothetical judgment cannot be con-
verted into a Categorical. For the thought,
Not convertible into ^ .^ through B, is wholly different from the
a Categorical. t/ • >i
thought, A is in B. The judgment — If God
is righteous, then will the tcicked he punished, and the judg-
ment— A righteous God punishes the wicked, are very different,
although the matter of thought is the same. In the former judg-
ment, the punishment of t/ie wicked is viewed as a consequent of
the righteousness of God ; whereas the latter considers it is an at-
tribute of a righteous God. But as the consequent is regarded as
something dependent from, — the attribute, on the contrary, as some-
thing inhering in, — it is from two wholly different points of view
1 Knig, Logik, § 67, Anna. S, p. 168. —So.
Lect. Xm. LOGIC. 169
that the two judgments are formed. The hypothetical judgment,
therefore, A is through B, is essentially different from the categori-
cal judgment, A is in B ; and the two judgments are regulated by
different fundamental laws. For the Categorical judgment as ex-
pressive of the relation of subject and attribute, is determined by
the laws of Identity and Contradiction ; the Hypothetical, as ex-
j)ressive of the relation of Reason and Consequent, is regulated by
the principle of that name." ^ So much for Hypothetical.
"Disjunctive judgments are those in which the condition qualify-
ing the relation between the subject and predi-
2. Disjunctive. => . . , . , ^. 7 ,
cate, lies proximately in the predicate, as in the
proposition, D is either B or C, or A. In this class of judgments a
certain plurality of attributes is predicated of the subject, but in
such a manner that this plurality is not predicated conjunctly, but it
is only judged that, under conditions some one, and only some one,
of this bundle of attributes appertains to the subject. When I say
that Ifen are either Black, or White, or Tawny, — in this proposi-
tion, none of these three predicates is unconditionally affirmed; but
it is only assumed that one or other may be affirmed, and that, any
one being so affirmed, the others must, ec ipso, be denied. The attri-
butes thus disjunctively predicable of the subject, constitute together
a certain sphere or whole of extension ; and as the attributes mutu-
ally exclude each other, they may be regarded as reciprocally reason
and consequent. A disjunctive proposition has two forms, according
as it is regulated by a contradictory, or by a contrary, opposition.
A is either B or not B, — This mineral is either a metal or not, — are
examples of the former ; A is either B, or C, orT>, — This m,ineral ^*
either lead, or tin, or zinc, — are examples of the latter. The oppo-
site attributes or characters in a disjunctive proposition are called
the Disjunct Members {membra disjuncta) ; and their relation to
each other is called the Disjunction (disjunctio), which in English
is expressed by the relative particles either, or {aut, vel), in conse-
quence of which these words constitute the Disjunctive particles
{particulce disjunctive). In propositions of this class the copula
is formed by either is, — or is, for hereby the concepts are brought
together so as to constitute a single object of consciousness, and
thus a synthesis or union of notions is effected."
" Now, although in consequence of the multiplicity of its predi-
cates, a disjunctive proposition may be resolved into a plurality of
1 Krug, Logik, f 57, p. 168, Anm. 2 — Ed. rule, Propositio Conditionalis nihil ponit in esse.
[Hypotheticals take account not of the cor- Christian Weiss, Lehrbuch der Logik, p. 109, ed.
rectness of the two clauses, but only of their 1801.]
connection (consequentia). Hence the logical
22
170 LOGIC. Lect. xm.
judgments, still it is not on that account a complex or composite
judgment. For it is realized by one simple energy of thought, in
which the two relatives — the either and the or
A Di^unctive judg- — are thought together, as inseparable, and as
ment, not in reality binding up the Opposing predicates into a single
composite, and not , -, /. ^i • n- • ^'
^■v.y • ^ /> i. sphere. In consequence ot this, a disiunctive
convertible into a Cat- ^ ^ '' j
egoricai. proposition cannot be converted into a categor-
ical. For in a categorical judgment a single
predicate is simply affirmed or denied of a subject ; wlicreas in a
disjunctive judgment there is neither affirmation nor negation, but
the opposition of certain attiibutes in relation to a cei'tain subject
constitutes the thought. Howbeit, therefore, that a disjunctive and
a categorical judgment may have a certain resemblance in respect
of their object matter ; still in each the form of thought is wholly
different, and the disjunctive judgment is, consequently, one essenti-
ally different from the categorical.'"
Dilemmatic judgments are those in which a condition is found,
both in the subject and in the predicate, and as
3. Dilemmatic. ... n i » . i /. t
thus a combmation of an hypothetical form and
of a disjunctive form, they may also appropriately be denominated
Hypothetico-disjunctwe. If X is A, it is either B or C — If an
action be prohibited, it is prohibited either by natural or by positive
law — If a cognition be a cognition of fact, it is giv^n either
through ayi act of external perception or through an act of self-
consciousness. In such propositions, it is not necessary that the
disjunct predicates should be limited to two ; and besides what are
strictly called dilemmatic judgments, we may have othei-s that would .
properly obtain the names of trilemmatic, tetralemmatic, polylem-
matic, etc. But in reference to propositions, as in reference to syl-
logisms, dilemma is a word used not merely to denote the cases
where there are only two disjunct membei-s, but is, likewise, extended
to any plurality of opposing predicates. There remains here, how-
ever, always an ambiguity ; and perhaps, on that account, the term
hypothetico-disjunctive might with propriety be substituted for dilem-
matic. A proj)Osition of this class, thougli bear-
A Dilemmatic judg- ing both an hypothetical and a disjunctive form,
ment indivisible, and cannot, howevcr, be analvzed into an hypotheti-
not reducible to a pin- i -i -i. . . . , t
raiity of categorical ^al and a disjunctive judgment. It constitutes
propositions. as indivisible a unity of thought as either of
these; and can as little as these be reduced
without distinction to a plurality of categorical propositions.
Every form of Judgments which we have hitherto considered,
1 Krug, Logik, pp. 170, 171. Compare Kant, Logik^ ) 29. — £d.
Lbct. xhl logic. ITl
has its corresponding form of Syllogism ; and it is as constituting
the foundations of different kinds of reasoning, that the considera-
tion of these different kinds of propositions is of principal impor-
tance. These various kinds of propositions may,
Judgments consid- however, be considered in the different points of
^nanwt '*^*"°'"' ^^ "^^^^ ^^ Quantity, Quality, and Relation. And
firet of Quantity ; in reference to which I give
you the following paragraph.
% L. The Quantity of Judgments has reference to the whole
of Extension, by the number of the objects
Par. li. 10. The com- conccming which we judc;e. On this I
mon doctrine of the , ,, .11,0 ^r^^^ 1 • i»
division of judg- shall State articulately, 1 , Ihe doctrme ot
menta according to tjjg Logiciaus ; and, 2°, The doctrine which
their Quantity. 2°. _ . , ,
The doctrine of the I conccivc to be the morc correct,
author on this point. 1°. (The doctrinc of the Logicians.) The
common doctrine, which, in essentials, dates
from Aristotle,^ divides Propositions according to their Quan-
tity into four classes ; viz., (A) the Universal or General {pr.
universales, generates, Trporacrets aX koBoXov) ; (B) the Particular
{pr. particulares irpoToicrcLi /xcpiKai, at iv fiipet) ; (C) the Individ-
ual or Singular {pr. individuales, singulares, expositorice, irpo-
rao-cts at KoSt' Ikoxttov, to, arofia) ; (D) the Indefinite {pr. imprcB-
finitce, indefitlitce, Trporacrcis dSiopio-rot, ctTrpoo-Sto/ato-TOi) . They
mean by universal propositions, those in which the subject is
taken in its whole extension ; h^ particular propositions, those
in which the subject is taken in a part, indefinitely, of its exten-
sion ; by individual propositions, those in which the subject is
at a minimum of extension ; by indefinite propositions, those
in which the subject is not articulately or overtly declared to
be either universal, particular, or individual.
2°. (The doctrine I prefer.) This doctrine appears to me
untenable, and I divide Propositions according to their Quan-
tity in the following manner : — In this respect their differences
arise either (A), as in Judgments, from the necessary condition
of the Internal Thought; or (B), as in Propositions, merely
from the accidental circumstances of its External Expression.
Under the former head (A), Judgments are either (a) of
Determinate or Definite Quantity, according as their sphere is
circumscribed, or (b) of Quantity Indeterminate or Indefinite,
according as their sphere is uncircumscribed. — Again, Judg-
ments of a Determinate Quantity (a) are either (1) of a Whole
1 D« Interp., o. 7. Andt. Prior,, i. 1. — Ed.
172
LOGIC.
lkct. xm.
Undivided, in which case they constitute a Universal or Gerv-
eral Proposition ; or (2) of a Unit Indivisible, in which case,
they constitute an Individual or Singular Proposition. — A
Judgment of an Indeterminate Quantity (b) constitutes a, Par-
ticular Proposition.
Under the latter head (B), Propositions have either, as prop-
ositions, their quantity, determinate or indeterminate, marked
out by a verbal sign, or they have not ; such quantity being
involved in every actual thought. They may be called in the
one case (a) Predesignate ; in the other (b) Preindesignate.
Again, the common doctrine, remounting also to Aristotle,'
takes into view only the Subject, and regulates the quantity of
the proposition exclusively by the quantity of that term. The
Predicate, indeed, Aristotle and the logicians do not allow to be
affected by quantity ; at least they hold it to be always Particu-
lar in an Affirmative, and Universal in a Negative Proposition.
This doctrine I hold to be the result of an incomplete analy-
sis; and I hope to show you that the confusion and multiplicity
of which our present Logic is the complement, is mainly the
consequence of an attempt at synthesis, before the ultimate ele-
ments had been fairly reached by a searching analysis, and of a
neglect, in this instance, of the fundamental postulate of the
science.
(Mental) Jadgments
of a Whole Undivided -
a \ Universal or General Jadgments.
of Determinate or ,
\ Definite Quantity.
of a Unit Indivisible —
. y Individual or Singular Judgments,
of Indeterminate or
Indefinite Quantity — forming Particular Judgments.
3 i their Quantity Expressed — Predesignate.
(Verbal) Propositions } b
/their Quantity Not Expressed — Preindesignate.'
1 Of. Inttrp , c. 7. — Ed.
'i Vide Th. et Am. apud Am In Dr. Int.,
8vo, ff. 72, 111—113. [In the first of these
pascaj^eB, Ammoiiius, proceeding on a merely
arithmetical calculation, enumerates sixteen
varieties of the Proposition, any one of four
(|uantities in the subject, — [all — vot nil, none
— not none or some), being capable of combi-
iiatiuD with any one of four quantities in the
predicate. But of these some are but verbal
varieties of the same judgment, and others
are excluded on material grounds, so that his
division Anally coincides with Aristotle's. In
the second passage Theophrastus is cited in
illustration of a very obscure statement con-
cerning the opposition of iudesignatc propo-
sitious. — £d.]
Lect. Xm. LOGIC. 173
Universal Judgments are those in which the whole number of
objects within a sphere or class are judged of, —
Explication. Uni- ^ ^^^ ^^^^ ^^^ mortaL or Every man is mortal,
versalJudgments. , „ . , •, r> ■ i 11 1
the all in the one case denning the whole col-
lectively, — the evenj in the other defining it discretively. In such
judgments the notion of a determinate wholeness or totality, in the
form of omnitude or allness, is involved.
Individual Judgments are those in which, in like manner, the
whole of a certain sphere is judged of, but in
Singular or indi- j^j^^ sphere there is found only a single object,
vidual Judgments,— ^ , ^ . , , . % .,. .
^ijj^t or collection of single objects, — as Cahline ts
amhitious, — The ticelve apostles icere inspired.
In such judgments the notion of determinate wholeness or totality
in the form of oneness, indivisible unity, is involved.'
Particular Judgments are those in which, among the objects
within a certain sphere or class, we judge con-
a "C"" " g cerninff some indefinite number less than the
ments, — what. o
whole, — as Som,e men are virtuous — Many
hoys are courageous — Most women are compassionate. The indef-
inite plurality, within the totality, being here denoted by the words
some, many, m,ost. There are certain words
Words which serve which scrve to mark out the quantity in the case
to mark out quantity ^f Universal, Individual, and Particular propo-
in Universal, Individ- . . _, i • 1 t • •
uai, and ParUcuiar sitions. The words which designate univer-
Propositions. sality are all, the whole of, every, both, each, none,
no one, neither, always, everywhere, etc. The
words which mark out pai;ticularity are som,e, not all, one, two, three,
etc., sometimes, somewhere, etc. There are also terms which, though
they do not reach to an universal whole, approximate to it, as many,
most, almost all, the greatest part, etc., few, very few, hardly any,
etc., which, in the common employment of language, and in refer-
ence to merely probable matter, may be viewed as almost tanta-
mount to marks of universality.
By logicians in general it is stated, that, in a logical relation,
an Individual is convertible with an Universal
Distinction of Uni- proposition ; as in both something is predicated
versai and Individual ^^ ^ ^^j^^j^ subject, and neither admits of any
from Particular Judg- . -r, i-i
ments. exception. But a Particular Judgment, like-
wise, predicates something of a whole subject,
and admits of no exception ; for it embraces all that is viewed as
the subject, and excludes all that is viewed as not belonging to it.
' Individuum (proprium ) signatum, and indi- particulare vagum. The former of each, and th»
vidwum vagum. So particulare signatum, and latter of each, corresponding. — Memoranda.
174 LOGIC. Lect. xiu.
The whole distinction consists in this, — that, in Universal and in
Individual Judgments, the number of the objects judged of is
thought by us as definite ; whereas, in Particular Judgments, the
number of such objects is thought by us as iudefinite. That Indi-
vidual Judgments do not correspond to Universal Judgments, merely
in virtue of the oneness of their subject, is shown by this, — that, if
the individual be rendered iudefinite, the judgment at once assumes
the character of particularity. For example, the propositions, — A
German invented the art of printing^ — An Englishman generalized
the laxo of gravitation, — are to be viewed as particular propositions.
But, if we substitute for the indefinite expressions a German and
an Englishman, the definite expressions Faust and Newton, the
judgment obtains the form of an universal.
With regard to quantity, it is to be observed, say the logicians, that
Categorical Judgments are those alone which
Categorical Jadg- admit of all the forms. " Hypothetical and Dis-
ments alone, accord- junctivc propositions are always universal. For
ing to logicians, admit . , i • i i i • • f
of all the forms of »» hypotheticals, by the position of a reason,
quantity. there is posited every consequent of that reason ;
and in disjunctives the sphere or extension of the
subject is so defined, that the disjunct attributes are predicated of
the whole sphere. It may, indeed, sometimes seem as if in such
propositions something were said of some, and, consequently, that
the judgment is particular or indefinite. For example, as an hypo-
thetical, — If some men are learned, then others are unlearned ; as
a disjunctive, — Those men who are learned are either philosophers
or not. But it is easily seen that these j lodgments are essentially of
a general character. In the first judgment, the real consequent is, —
then all others are unlearned; and in the second, the true subject is,
— all learned m,en, for this is involved in the expression — Those
men tcho are learned, etc."^
Such is the doctrine of the Logicians. This I cannot but hold
to be erroneous ; for we can easily constnict
This doctrine errone- . . i ^i_ i ^i ^' i j- •
proposition.s, whether hypothetical or disjuni--
tive, which cannot be construed either as uni-
vei*sal or singular. For example, when we say,hypothetically, — If
some Dodo is, then some animal is; or, disjunctively, — Som.e men
are eit/ier rogues or fools : — in either case, the proposition is indefi-
nite or particular, and no ingenuity can show a plausible reason why
it should be viewed as definite, — as general or individual.
1 Krug, Logik, ) 67, Anm. 4, p. 171 et seq. — i. § 122. Schulze, Logik, S 60. Conira ,- — £»•
Ed. [Cf liofTbaucr, An/angsgrtinke der Logik, ser, Logik, § 92, p. 177. — [See below, p. 887
S 243. Sigwart, Lngik, ) 1G4 tt seq.,ed. 1835. note L — Ed.]
Kiesewettcr, Gruadriss einer allgrtneintn Logik.
LECTURE XIV.
STOICHEIOLOOY.
SECTION II.— OF THE PRODUCTS OF THOUGHT,
II. — APOPHANTIC.
JUDGMENTS. — THEIR QUALITY, OPPOSITION, AND CONVERSION.
The first part of our last Lecture was occupied witli the doctrine
of Judgments, considered as divided into Simple
ecapi u a ion. ^^^ .^^^ Conditional ; Simple being exclusively
Categorical, Conditional, either Hypothetical, Disjunctive, or Hypo-
thetico-disjunctive. We then proceeded to treat of the Quantity
of propositions, and, in this respect, I stated that they are either
Definite or Indefinite ; the Definite comprising the two subordinate
classes of General or Universal, and of Singular or Individual
propositions, while the Indefinite are correspondent to Particular
propositions alone. In regard to the terms definite and indefinite^ I
warned you that I do not apply them in the sense given by logical
writers. With them. Indefinite propositions denote those in which
the quantity is not explicitly declared by one of the designatory
terms, all, every, some, many, etc Such propositions, however,
ought to be called pre-hidesignate {^prcB-indesignatm, airpoaSiopLcrToi),
that is, not marked oxit by a prefix, — a term better adapted to indi-
cate this external accident of their enunciation; for, in point of fact,
these preindesignate propositions are either definite or indefinite,
and quite as definite or indefinite in meaning, as if their quantity
had been expressly marked out by the predesignatory terms.
, , „ This being premised, I now go on to the next
Second division of ... ...
Judgments, or that ac- division of Judgments — the division proceed-
cording to tiieir Quai- ing On that ground which by Logicians has been
'*y* called the Quality of Judgments. In itself the
term quality is here a very vague and arbitrary expression, for w«
176 LOGIC. Lect. XIV.
I
might, with equal propriety, give the name of quality to several
other of the distinguishing principles of propositions. For example
the truth or falsehood of propositions has been also called their
quality; and some, logicians have even given the n.ame of quality
to the ground of the distinction of judgments into categorical, hypo-
thetical, and disjunctive. What, however, has been universally, if
not always exclusively, styled the quality of propositions, both in
ancient and modern times, is that according to which they are dis-
tributed into Affirmative and Negative.
^ LI. In respect of their Quality, Judgments are divided into
two classes. For either the Subject and
Par. LL Jndsrments, -r» ,. ^ i_ • j „
in respect of their Jr rcdicatc may be recognized as reciprocally
Quality, are Afflrma- containing and contained, in the opposite
tlve and Negative. .. n t\ • i i~^
quantities of Extension and Comprehen-
sion ; or they may be recognized as not standing in this rel.a-
sion. In the fomier case, the subject and predicate are affirmed
of each other, and the proposition is called an Affirmative
(Trporao-is KaracfMTucq or Karqyopucr), Judicium affirmativum or
positivum) ; in the latter case, they are denied of each other,
and the proposition is called a Negative (irpOTao-is d7ro<t>aTucq or
areprjTucq., Judicium negativum).
In this paragraph, I have enounced more generally than is done by
logicians the relation of predication, in its affirmative and negative
phases. For their definitions only apply cither to the subject or to
the predicate, taken as a whole ; whereas, since
Explication. Gen- ^g jugy indiffisrcntly view either the subject as
fr'^r** A-^ .-^ "' the whole in relation to the predicate, or the
tion of predication in ^ . .
tiie paragraph. predicate as the whole in relation to the subject,
according as we consider the proposition to ex-
press an intensive or to express an extensive judgment, — it is
proper in our definition, whether of predication in general, or of
affirmation and negation in particular, to couch it in such terms that
it may indifferently comprehend both these classes, — both these
phases, of propositions.
As examples of Affinnative and Negative propositions, the follow-
ing may suffice : — A is B — A is not B — God
rma i\ea eg ^.^ merciful — God ts uot vindictive. In an Af-
ative Propositions. •'
firmative judgment, there is a complete inclusion
of the subject within the predicate as an extensive whole ; or of
the predicate within the subject as an intensive whole. In Nega-
tive judgments, on the contrary, there is a total exclusion of the
JjBCT. XIV. lOGlO. ft*T
subject from the sphere of the predicate (extensively), of of the
predicate from the comprehension of the subject (intensively). In
affirmative propositions there is also distinctly enounced through
what predicate the notion of the subject is to be thought, that is,
what predicate must be annexed to the notion of the subject ; in
negative propositions, in like manner, it is distinctly enounced
through what predicate the notion of the subject is not to be
thought, that is, what predicate must be shut out from the notion of
the subject. In negative judgments, therefore, the negation essen-
tially belongs to the Copula ; for otherwise all propositions without
distinction would be affirmative. This, however, has been a point
of controversy among modem logicians ; for many maintain that the
negation belongs to the predicate, on the follow-
That Negation does jng grounds : — If the negation pertained to the-
not belong to the Cop- p^, ,j ^jje^e couM be no synthesis of the two
tilft, held by some logi- * •'
cjans. terms, — the whole act of judgment would be
subverted, — while at the same time a non-con-
necting copula, a non-copulative, is a contradiction in terms. But
a negative predicate, that is, a predicate by which something is-
taken away or excluded from the Subject, involves nothing con-
tradictory ; and, therefore, a judgment with such a predicate is ■
competent.^
The opposite doctrine is, however, undoubtedly the more correct.
For if we place the negation in the predicate,
The opposite doctrine negative judgments, as already said, are not dif-
maintainedbytheAu- /. ^ • r. j. jn .• i. • i
jjjop lerent in lorm Irom affirmative, being merely
affirmations that the object is contained within
the sphere of a negative predicate, or that a negative predicate
forms one of the attributes of the subject. This, however, the
advocates of the opinion in question do not venture to assert. The
objection frpm the apparent contradiction of a non-connecting cop-
ula is valid only if the literal, the grammatical, meaning of the
term copula be coextensive with that which it is applied logically to
express. But this is not the case. If literally taken, it indicates
only one side of its logical meaning. What the
True import of the j 7 .j xij^-au
word copula very inadequately denotes, in the
form of the relation between the subject and
predicate of a judgment. Now, in negative judgments, this form
1 Krug, Logik, § 55, Anm. 3. — Ed. [Com- Bardili, Gntndriss der ersten Logik, § 12. Der-
pare on tlie same side BuflBer, Logique, i., §75 odon, Logiea, p. 642. Cf. p. 515 tt seq. Com-
et seq. Bolzano, Wiessenscha/tsle/tre, Lagik, voL tra ; — Kant, Logik, f ffi, Anm. 3. Baehmann,
ii., H 127, 129, 136. Schulze, X^gii, j 60, p. 74. iogi*, » 84, p. 127. Eager, iog*, » 59, p. 116-1
23
178 LOGIC. Jjeot. XIV.
eesentially consists in the act of taking a part out of a whole,
and is as necessary an act of thought as the putting it in. The
notion of the one contradictory in fact involves the notion of the
other.^
The controversy took its origin in this, — that every negative
judgment can be expressed in an affirmative
Origin of the contro- f^^^^ ^y^^^ ^^le negation is taken from the cop-
pi«ce of negation "'^ ^^^ placed in the predicate. Thus, A is not
B may be changed into, — A is not-3. The con-
trast is better expressed in Latin, A non est B — A est non-B. In
fact, we are compelled in English to borrow the Latin Jion to make
the difference unambiguously apparent, saying, A is non-B, instead
of A is 7iot-B. But this proves nothing; for by this transposition
of the negation from the copula to the predicate, we are also ena-
bled to express every affirmative proposition through a double nega-
tion. Thus, A is B, in the affirmative form is equivalently enounced
by A is not non-B — A non est non-B, in the negative.
This possibility of enunciating negative propositions in an afiSrma-
j., tive, and affirmative propositions in a negative
Negative temw,— form, has been the occasion of much perverse
how designated by Ar- _ i • • » • , o i
j^^jyg • rennement among logicians. Aristotle * denom-
inated the negative terms, such as 7Jon B, non
homo, non albus, etc. ovofjutm aopurra, literally, indefinite nou7is, Boe-
thius,' however, unhappily translated Aristotle's Greek term aopur-
Tos by the Latin infinitus, reserving the term
^ ** *"■ indefitiitus to render d&dpioros as applied to
propositions, but of which the notion is more appropriately ex-
pressed, as we have seen, by the word indesignate (indesignatus),
or better preindesignate {prcBxndesignatus). The Schoolmen, fol-
: >, lowing Boethius, thus called the ovofiara aopwra
of Aristotle nomina infinita : and tjie non they
Btyled the particula infinitans. Out of such elements they also
constructed Propositiones Infinites; that is, judgments in which
either the subject or the predicate was a nega-
Propositum*s infiniuB ^j^^ notion, as non-homo est viridisy and homo
of the achoolmen,— . . ■,. -, , , •.• • • i j
^,,,t est non-vtrtdis, and these they distinguished
from the simple negative, homo — non est — vir-
idis. Herein Boethius and the schoolmen have been followed by
Kant,* through the Wolfian logicians ; for he explains Infinite Judg-
1 Bacbnann, Logik, p. 127. — Ed. 4 Logtfc, { SS. Compare Wolf, FkUo*. Ro-
S D« Ilerpretatione, o. 2. — £d. I»o«., } 209. — Ed.
^ In De Inttrpretationtf L. il. ) 1. Optra, p.
860. — Ed.
I
Lect. XIV. LOGIC. It9
ihents as those which do not simply indicate, that a subject is not
contained under the sphere of a predicate, but that it lies out of its
sphere, somewhere in the infinite sphere. He has thus considered
them as combining an act of negation and an
On this point foi- ^^^^ ^f affirmation, inasmuch as one thing is
lowed by Kant. /« -i • i i t i • /•
affirmed m them through the negation oi an-
other. In consequence of this view, he gave them, after some
Wolfians, the name of Limitatwe, which he constituted as a third
form of judgments under quality, — all propositions being thus
either Affirmative, Negative, or Limitative. The whole question
touching tiie validity of the distinction is of no practical conse-
quence ; and consists merely in whether a greater or less latitude is
to be given to certain terms. I shall not, therefore, occupy your
attention by entering on any discussion of what may be urged in
refutation or defence. But if what I have al-
Kant'8 three-fold di- ready Stated of the nature of negation and its
vision of Propositions . . , , , , , .
unfounded. Connection with the copula, be correct, there is
no ground for regarding limitative propositions
as a class distinct in form, and coordinate with Affirmative and Neg-
ative judgments,'
If we consider the quantity and quality of judgments as com-
bined, there emerges from this juncture four separate forms of prop-
.ositions, for they are either Universal Affirmative, or Universal
Negative, Particular Affirmative, or Particular Negative. These
forms, in order to facilitate the statement and analysis of the syllo-
gism, have been designated by letters, and as it is necessary that
you should be familiar with these symbols, I shall state them in the
following paragraph.
^ LII. In reference to their Quantity and Quality together.
Propositions are designated by the vowels
o/'prop^siti^rs'ae" ^' E, I, O. The Universal Affirmative are
cording to their dcuotcd by A ; the Universal Negative by
urniUl'e?'^"'^ E; the Particular Affirmative by I; the
Particular Negative by O. To aid the
memory, these distinctions have been comprehended in the
following lines :
Asserit A, negat E, sed universaliter ambae,
Asserit I, negat 0, sed particulariter ambo.^
1 Compare Kmg, Logik, f 65. Anm. 2. — 2 Petms Hispanns, SHmmulai, Tract, r. par-
Ed. [Against the distinction, see Bachmann, tic. 4, f. 9. Cf Petrus Tartaretns; ExpoaitU
Logik, § 84, p. 128. Schulze, Logik, J 50. in 5u»imui<M, Tract i. f. 9 b. — Ed.
Drobisek, ( 42.]
180
Loorc.
Lkct. XIT.
I may here, likewise, show you one, and perhaps the best, mode,
in which these different forms can be expressed by diagrams.
Tlie first employment
of circular diagrams
in logic improperly
tMcribed to Euler. To
be found in Christian
Weise.
The invention of this mode of sensualizing by circles the abstrac-
tions of Logic, is generally given to Euler, who
employs it in his Letters to a German Princess
071 different Matters of Physics ayid Philosophy}
But, to say nothing of other methods, this by
circles is of a much earlier origin. For I find
it in the JVudeus Logicoe Weisiance, which ap-
peared in 1712; but this was a posthumous publication, and the
author. Christian Weise, who was Rector of Zittau, died in 1708.
I may notice, also, that Lambert's method of
LBmberfs method accomplishing the same end, by parallel lines
to be found in Aste- «.,./« / , . i *» i • ^ -r •
jj^g of different lengths, is to be found in the Liogxc
of Alstedius, published in 1614, consequently
above a century and a half prior to Lambert's Neues Organon? Of
Lambert's originality there can, however, I think, be no doubt; for
he was exceedingly curious about, and not overlearned in, the his-
tory of these subsidia, while in his philosophical coiTcspondence
many other inventions of the kind, of far inferior interest, are
recorded, but there is no allusion whatever to that of Alstedius.
Before leaving this part of the subject, I may take notice of another
1 P«rtieii.,Lcttrexxxv.,ed.Coumot.— Ed. Logieer, S^atema Harmonieum of AlMcdiofi
* A rery imperftct diagram of this kind, (1614), p. 395. Lambert's diagrams ( A>ik« O-
with the lines of equal length, in illustration ganon, vol. i. p. Ill tt nq.) are muoh nun
of the first syllogistic figure, is given in the complete. — Ed.
I
hmxK. XIY. LOGIC. 181
cUvisioQ of Propositions, made by all logicians — viz., into I^ure and
Modal. Pure propositions are those in wliich the predicate is cate-
gorically affirmed or denied of the subject, simply, without any qualifi-
cation ; Modal, those in which the predicate is categorically affirmed
or denied of the subject, under some mode or
Olgtinctiop of Fro- qualifying determination. For example, — ^^ejc-
pfieltions into Pure , t t^ • • < » 7
and Modal anoer conquered JJarius, is a pure, — A.lexancler
conquered Darius honorably, is a modal j^ropo-
iution.^ Nothing can be more futile than this distinction. The
mode in such propositions is nothing more than
This distinction futile.
a part oi the predicate. 1 he predicate may be
a notion of any complexity, it may consist of any number of attri-
butes, of any number even of words, and the mere circumstance
that one of these attributes should stand prominently out by itself^
can establish no diffei-ence in which to originate a distinction of the
kind. Of the examples adduced, — the pure proposition, Alexander
oonqticred Darius, means, being resolved, Alexander was the con-
queror of Darius, — Alexander being the subject, was the copula,
and the conqueror of Darius the predicate. Now, if we take the
modal, — Alexander conquered Darius honorably, and resolve it in
like manner, we shall have Alexander teas the honorable conquei-or
of Darius; and here the whole difference is, that in the second the
predicate is a litle more complex, being the honorable conqueror of
Darius, instead of the conqueror of Darius.
But logicians, after Aristotle,- have principally considered as
modal propositions those that are modified by
ivision o o a ^^^ ^^^^ attributions of Necessity, Impossibility,
Propogitions by logi- . . .1 > l rf>
cians. Medals as Contingence, and Possibility. But, in regard to
involving the consid- these, the case is precisely the same ; the mode
eration of the matter jg merely a part of the predicate, and if so,
of a proposition are , . , - , .
extra-logical. nothing can be more un wan-anted than on this
accidental, on this extra-logical, circumstance to
establish a great division of logical propositions. This error is seen
in all its flagrancy when applied to practice. The discrimination of
propositions into Pure and Modal, and the discriminatioja of Modal
propositions into Necessary, Impossible, Contingent, Possible, and
the recognition of these as logical distinctions, rendered it impera-
tive on the logician, as logician, to know what matter was neces-
sary, impossible, contingent, and possible. For rules were laid
.^ These medals are not acknowledged by by the Schoolmen. Compare Ammonia?, //»
A listotle, who allows only the four mentioned Be Interp., p. 148 b, ed. 1546.— Ed.
huiow. They appear, however, in his Greek 2 De Interp., c. 12. Compare AnaL Prior,, i,
commentators, and from tli«m were adopted 2. — £i».
182 LOGIC. Lect. xir.
doTm in regard to the various logical operations to which proposi-
tions were subjected, according as these were determined by a
matter of one of these modes or of another, and this, too, when the
modal character itself was not marked out by any peculiarity or
form of expression. Thus, to take one of many passages to the
same effect in Whately; speaking of the quality
Whately quoted. „ . . , ^ ' %_, *' , , ? %
oi propositions, he says, " When the subject of
a proposition is a Common-term, the tmiverscU sigiis (' all, no, every,')
are used to indicate that it is distributed (and the proposition con-
sequently is universal) ; the particular signs (' some, etc.'), the con-
trary. Should there be no sign at all to the common term, the
quantity o/ the proposition (which is called an Indefinite proposi-
tion) is ascertained by the matter; i.e., the nature of the connec-
tion between the extremes : which is either Necessary, Impossible,
or Contingent. In necessary and impossible matter, an Indefinite
is understood as a universal; e. g., birds have wings ; i. e., aU : birds
are not quadrupeds; i.e., none: in contingent matter (t. e., where
the terms partly (t. e. sometimes) agree, and partly not), an Indefi-
nite is understood as a particular ; e. g^ food is necessary to life ; ». «.,
smne food ; birds sing ; ». c, some do ; birds are not carnivorous ;
I. e., some are not, or all are not." ^
Now all this proceeds upon a radical mistake of the nature and
domain of Logic. Losjic is a purely formal
Criticized.
science ; it knows nothing of, it establishes noth-
ing upon, the circumstances of the matter, to which its form may
chance to be applied. To be able to say that a
On the supposition , . . ^ . ...
that LoRic takes cog- ^^'"8 '^ of necessary, mipossible, or contingent
ninnce of tiie modal- matter, it is requisite to generalize its nature
ity of object?, this from an extensive observation ; and to make it
scence can ia\e no incumbent on the logician to know the modality
existence. _ ....
of all the objects to which his science may Ik;
applied, is at once to declare that Logic has no existence; for this
condition of its existence is in every point of view impossible. It
is impossible — 1°, Inasmuch as Logic would thus presuppose a
knowledge of the whole cycle of human science ; and it is impossi-
ble — 2°, Because it is not now, and never will be, determined what
things are of necessary or contingent, of possible or impossible exist-
ence. Speaking of things impossible in nature, Sir Thomas Brown
declared that it is impossible that a quadruped could lay an e^^, ot
that a quadruped could possess the beak of a bird ; and, in the ago
of Sir Thomas Brown, these propositions would have shown as
I EUmenU o/Logik, book U. ohftp. ii. f 8, pp. 68, M.
I
Lect. XIV. LOGIC. 188
(rood a title to be regarded as of impossible matter as some of the
examples adduced by Dr. Whately. The discovery of New Hol-
land, and of the Ornithorhynchus, however, turned the impossible
into the actual; for, in that animal, there is found a quadruped
which at once lays an egg and presents the bill of a duck. On the
principle, then, that Logic is exclusively conversant about the forms
of thought, I have rejected the distinction of propositions and syl-
lo<Tisms into pure and modal, as extra-logical. Wliatever cannot be
stated by A, B, C, is not of logical import ; and A, B, C, know
nothing of the necessary, impossible, and contingent.^
It maybe proper, however, to explain to you the meaning of three
terms which are used in relation to Pure and
Explanation of three Modal propositions. A proposition is called
terms used in reference Assertory, wheu it cnounccs what is known as
actual : Problematic, when it enounces what is
Propositions. ' '
known as possible ; Apodeictic or Deinonstror
five, when it enounces what is known as ^necessary. ^
The last point of view in which judgments are considered, is their
Relation to each other. In respect of these rela-
Third Division of tions, propositions havo obtained from Logicians
Judgments— Relation . , i • t i i
each other particular names, which, however, cannot be un-
derstood without at the same time regarding the
matter which the judgments contain. As the distinctions of Judg-
ments and of Concepts are, in this respect, in a great measure analo-
gous, both in name and nature, it will not be necessary to dictate
them.
When the matter and form of two judgments are considered as
the same, they are called Identical, Convertible,
Judgments identi- Equal OX Equivalent {propositiones identicce,
pares, convertibiles, cequipollentes) ; on the oppo-
Different. site alternative, they are called Different {pr.
diverscB). If considered in certain respects the
Relatively Identical. Same, in others different, they are called Eela-
tively Identical, Similar, or Cognate {pr. rela-
tive identicce, similes, affines, cognatCB). This resemblance may
be either in the subject and comprehension, or in the predicate and
extension. If they have a similar subject, their
ispara e. predicates are Disparate (disparata), if a simi-
Disjunct. ^ar predicate, their subjects are Disjunct (dis-
Junctd).
I See JDucu«ion», p. 145 «««?. — Ed. [Com- Loffik, { 19. p. 72, and i 23, p. 79; Schnlaa^
pare Bacbmann, Logik, f 73, p. 115; Richter, Logik, § 52, p. 78.]
2 Kant, Logik, f 30.— Ed.
184 LOGIC. L»ox. XIV.
When two judgments diflfer merely in their quantity of exten-
sion, and the one is, therefore, a particular, the
other a general, they are said to be subordinated,
and their relation is called Subordination (sttbordinatio). The
subordinating (or as it might, perhaps, be more
properly styled, the super ordinate) judgment, is
called the Suhalternant {subaltemans) ; the subordinate judgment
is called the Subalternate {stibaltematum).
When, of two or more judgments, the one affirms, the other de-
nies, and when they are thus reciprocally difier-
^(^^witionof Judg- ^^^ jj^ quality, they are said to be Opposed or
CofiJHctive (pr. ojypositce, oLvTucciyxcvai), and their
relation, in this respect, is called Opposition (opjyositio). This oj)-
'- position is either that of Contradiciion or He-
.JCantradiotion. puqnance (contradictio. a.vr!.<i>axTi%), or that of
Contrariety. ^^"^ ^ ^ . , . \
Contrarietif {contrartetas, evan-ion/s).
If neither contradiction nor contrariety exists, the judgments are
called Congruent (pr. congruentes^ consonantes^
^ongruen u g- consentientes) . In regard to this last statement,
you will find in logical books, in general,' that
^bcoDtrary oppod- ^j^^^.^ j^ ^^ opposition of what are called Sub-
contraries (svbcontraria), meaning by these par-
ticular propositions of different quality, as, for example, some A are
B, some A are not B ; or, som,e men are learned, some men are
not learned; and they are called Sitbcontraries, as they stand sub-
ordinated to the universal contrary propositions, — All A are B, no
A t» B ; or. All men are learned, no man is learned. But this is a
mistake, there is no opposition between Subcon-
^^j*ot a real opposi- trarics ; for both may at once be maintained, a^
both at once must be true if the some be a nega-
tion of all. They cannot, however, both be false. The opposition
In this case is only apparent;' and it was probably only laid down
fK)m a love of symmetry, in order to make out the opposition of *11
the comers in the square of Opposition, which you will find in
almost every work on Logic.
t Elements of Logik, by Dr. Whately, part Com'mfcnwiMM JVora Z.o^Va, Tract iii. DJ»p.iti.,
ti. «twp. ti. i S, p. 68, ad edit. But see Soheib- f 2, p. 124, edit. ITll. Kant expressly rt^ects
le|\ Ofrrn I^jgica^ I'ars iii. c. xi. p, 48T, ed. Svtiicaiitrariety, Logik, f 50. Aiim. Compare
lflG6. Ulricli, llnstit. Log. ft Met, i 1S3, p. Krug, Logi^, f 64, Anm. 4. Braiiiss, Grundnss
190. — Ed.] dtr Logile, p. W&. Denzingur, iHstitutionet
t For which reason Aristotle describes it as Logica, vol. ii. } 713, p. 138. Cararauel, p 38
mk oppoeition ia language, hut not in reality. [RatienaUt tt Rtalis PkiioMpkia
Anal. Prior., ii. 15. — Ed. [Compare Fonseea, Caramutl LaUeatoitx, S. 1%. Lavmtiamti
JnstU. DiaUet., L. iii. c. 6, p. 129, ed. 1604. 4M<U« Mttfensi, Lovanii, 1642. —Ed ]
Lect. XIV.
LOGIC.
196
Terms employed to
t'.euote the original
and converted propo-
sition.
pfop., convertens).
Finally, various relatioas of judgments arise from what is called
their Conversion. When the subject and predi-
CooverBiou of Pro- ^.^^^ jj^ g^ categorical proposition (for to this wo
positions. t , • ^ • \ -11
now limit our consideration) are transposed, the
proposition is said to be converted ; the propositiou given and its
|)rodnct are both called the jadicia conversa; the relation itself of
reciprocation in which the judgments stand is called Conversion^
sometimes Obversion and Transposition {reciprocatio^ conversio,
obversio, transpositlo, /icra^ccrts, fieTa^oXrj, avTUf-
Tpo<f>^). The given proposition is called the
Converted or Converse (Judicium^ proposition
prcejaeens, conversum, eonversa) ; the other, into
which it is converted, the Converting (Jud.,
There is, however, much ambiguity, to say the
least of it, in the terms commonly employed by Logicians to des-
ignate the two propositions, — that given, and that the product of
tlic logical elaboration. The prejacent and subjacent may pass, but
they have been very rarely employed. The term 2}ropositio con-
u<9rsflr, the converse or converted judgment, specially for the original
proposition, is worse than ambiguous ; it is applied generally to both
judgments; it may, in fact, more appropriately denote the other, —
its product, — to which indeed it has, but through a blunder, been
actually applied by Aldrich,^ and he is followed, of course, by
Whately. The original proposition ought to be called the Convert-
end or Convertible {pr. convertenda, convertibilis)? The terra CoTirr
verting {convertens) employed for the proposition, the product of
conversion, marks out nothing of its peculiar
roposttxs txposua— eharactcr. The expression pr. exposita, applied
Its use by Aid rich er- „ . ' » i
roneous. by Aldrich," without a word of comment, to this
judgment, is only another instance of his daring
ignorance ; for the phrase pr. eocposita had nothing to recommend
it in this relation, and was employed in a wholly different meaning
by logicians and mathematicians.* In this error Aldrich is followed
1 B-mlirnentt^ Logic«B, L. 1. c. ii.
2 [So NoJdiug, p. 263, [LogUa Recognita, Haf-
aiae, 1766. — Ed.]
3 Crakanthorpe, Sanderson, and Wallis [de-
nominate the original proposition pr. con.'
versa, its product pr. convertens. See Crakan-
tliorpe, Logica, L. iii. c. 10, p. 179, ed. 1677.
Sanderson, Logica, L. ii. 0. 7, p. 76, ed. 1741.
Wallis, Institutio Logicce, L. ii. c. 7, p 113,
edit. 1729, Wallis alsQ uses pr. convtrtettda as
a synonym for pr. conversa. — Ed.]
* The term exposition ((K^tffis) is employed
by Aristotle, and by most subseqaent logi-
cians, to denote the seleotiou of an individual
instance whose qualities may be perceived by
sense (iKTi^tyai, exponere, objicere sensui), in
order to prove a general relation between no-
tions apprehended by the intellect- Thici
method is used by Aristotle in proving the
conversion of propositions and the reduction
of syllogisms. See Anal. Prior . i. 2; i. 6; i. 8.
The instance selected is called the expasitum.
(tJi iKTtbiv); and hence singular propwitiona
aad syllagisKks are called to^ositonj. Compare
Pacius on Anal. Pr., i. 2, and Sir W. Hamil'
ton's note, Reicfs Works, p. 696. — Ed.
24
186 LOGIC. Lkct. XIV.
by Whately, who, like his able pi'edecessor, is wholly unversed iu
the literature and language of Logic.
The logicians after Aristotle have distinguished two, or, as we may
take it, three, or even four, species of Conver-
Species of Conver- gion
logicUms!"^'* * ^ ^' ^^^ ^^*' which is called Simple or Pure
Conversion (conver sio simplex, tois opois ttpoi; eav-
njv, Aristotle, *. e^ curn terminis reciprocatis)^ is when the quantity
and quality of the two judgments are the same. It holds in Uni-
versal Negative and Particular Affirmative propositions.
2. The second, which is called Conversion by Accident {c. per ac
cidens^ iv fj.€pei, Kara fiipo';, Aristotle), is when, the quality remaining
unaltered, the quantity is reduced. It holds in Universal Affirma-
tives. These two are the species of the conversion of propositions
acknowledged by all ; they are evolved by Aristotle, not, as might
have been expected, in his treatise On £nounc€tne?it, but in the sec-
ond chapter of the first book of his Prior Analytics?
3. The third, which is called Conversion by Contraposition (c.
per oppositioneniy c. per contra positionem^ both by Boethius,' con-
traposition avTL(jTpo<f}T^ <rvv avTiSta-u, Alexander),* is when, instead of
the subject and predicate, the quantity and quality remaining the
same, there is placed the contradictory of each. This holds in Uni-
versal Affirmatives, and most logicians allow it in Particular Nega-
tives. It is commemorated by Aristotle in the eighth chapter of the
second book of his Topics : it is there called the inverse consecution
from contradictions.
I shall here mention to you some mnemonic verses in which the
doctrine of conversion is expressed.
Mnemonic verses ex- loii j* • i*-..!*.*!
1 . liegardmg conversion as hmited to tlie
pressing conversion. , ° .
Simple and Accidental, and excluding altogether
Contraposition, we have the doctrine contained in the two following
verses.
1 Toij %pois i.trruTrpi(ptiV, Anal. Pr., I. 2, logismo Categorico,!.. i., p. 5S7. Thus Mnr<».«io
i.e., when each term is the exact equivalent *» divided primarily into c. simpUx and c. per
of the other. See Trendelenburg, EUi}xenia contrapositionem. Aristotle does not use iy
Log. Ari.U., iU; In De Anima, p. 408; WaiU, ^*^*'. »« subsequent logicians, for c. diminuta.
In Arist. Org., vol. i. p. 373 — Ed. !*<= "^^ '^ mainly tor particular in opposition
2 [Boethius seems the first who gave the to univer.'ial. (See Anal. Prior, i. 2, » 4.) They
name of Cont^rsio prr Accidens. With him it »'^ «hus wrong in their use of the words oe<-.-.
Is properly both Ampliative and Kestrictive. ''"""^ »'><1 partial.]
(So Ridiger, De Sensu Veri et FaUi, pp. 250, , j„troductio ad Syllogismos Categorios, and
803, 2d edit., 1722. Fischer Logik, p. 108.) It ^ Syttogismo OUtgorico, L. 1. - Ed.
is opposed as a oonspecies to c. genrralis, and
both are sjiecies of c. simplex, which is op- * In Anal. Prior., £ 10 b, edit. Aid. 1620. -
posed to Contrapositioo. See Opera, D* Syl- Eo.
k
Lect. XIV. LOGIC. 19i
£, I, simpliciter vertendo, signa manebont;
Ast A cum vertis, signa minora cape.i
O is not convertible.
2°. Admitting Contraposition as a legitimate species of conver-
sion, the whole doctrine is embodied in the following verses by
Petrus Hispanus:
F E c I (F E s I) simpliciter, convertitar E v A (E p A) per Acdd,
Ast O (A c 0) per Contrap.; sic fit conversio tota.2
Or, to condense the three kinds of conversion with all the propo-
sitions, prejacent and subjacent, in a single line :
"EccE, TiBi, Simp. ; Abmi — geros, 4cc. ; Arha, bono, Cont."^
It may be proper now to make you acquainted with certain dis-
tinctions of judgments and propositions, which,
Distinction of Pro- tj^Qugh not Strictly of a logical character, it is
, positions not strictly i_iju v
, j^jjjj oi importance that you should be aware oi.
"Considered in a material point of view, all
judgments are, in the first place, distinguished into Theoretical and
Practical. Theoretical are such as declare that
core ica an rac- ^ certain character belongs or does not belong
tical. *= ^
to a certain object; Practical, Bwch. as declare
that something can be or ought to be done, — brought to bear."
"Theoretical, as well as practical judgments, are either Indemorir-
strable, when they are evident of themselves —
Indemonstrable and i ^i, j j. • i ^ ^\
^ , ^, when they do not require, and when thev are
Demonstrable. , •' ^ ^ «
incapable of proof: or they are Demonstrable,
when they are not immediately apparent as true or false, but require
some external reason to establish their truth or falsehood."
" Indemonstrable propositions are absolute principles {apx^-h pi'it^
cipia) ; that is, from which in the construction of a system of
science, cognitions altogether certain not only are, but must be
derived. Demonstrable propositions, on the other hand, can, at
best, constitute only relative principles ; that is, such as, themselves
requiring a higher principle for their warrant, may yet afford the
basis of sundry other propositions."
1 [Given by Chauvin, Lex Phil., v. Conversio. Tartaretns, Eipositio in Summulas Petri Hit-
Denzinger, Institutiones Logica, ii. 140.] pani, Tract, i., f, 9 b. — Ed.]
2 See Petrus Hispanus, p. 9, [Summuka,
Tract 1., partic. 4, f. 9, ed 1505. C£ Petrus 3 [Hispanus, Summulat, I. e. Chaarin, I. e.\
l.$8 LOGIC. tKCT. :ja •.
" If the indemonstrable propositions be of a theoretical character,
they are called Axioms; if of a practical churac-
Axioms and Portu- Postulates. The former are principles of
liites. . . ,
immediate certainty; the latter, principles of
immediate application.'*
" Demonstrable propositions, if of a theoretical nature, are called
Theorems (theoremata) ; if of a practical, Prob-
^^Theorems and Trob- ^^^^^ {problemuta). The former, as propositions
of a mediate certainty, require proof; they,
therefore, consist of a Thesis and its Demonstration/ the latter, as
of mediate ajjplication, suppose a Question {qucestio) and its iSolu-
tiou (resolidio).^^
" As species of the foregoing, there are, likewise, distinguished
Corollaries (consectaria. coroUaria), that is,
propositions which flow, without a new proof,
out of theorems or postulates previously demonstrated. Proposi-
tions whose validity rests on obsenatiou or ex-
^pei^uneuui Propp- periment are called Experiential, Experimental
propositions {empiremata^ experienticBy eacperi-
menta). Hypotheses^ that is, propositions which are assumed with
probability, in order to explain or prove some-
jp 1C8C8. thing else which cannot otherwise be explained
or proved. lemmata, that is, propositions borrowed from another
science, in oi'der to serve as subsidiary proposi-
tions in the science of which we treat, r mally,
SchoUa-y that is, propositions which only serve as illustrations of
what is considered in chief. The clearest and
most appropriate examples of these various
kinds of propositions are given in mathematics.'' '
, LofU, I 79, pp. liT, M8. — Kd. [OompueKnig.LofOs fi 87,66.]
i •> .5 ,(;iVU. (1-J
0':t
LECTURE XV.
STOICHEIOLOGY.
SECTION II. — OF THE PRODUCTS OF THOUGHT
in. — THE DOCTRINE OF REASONINGS.
REASONING IN GENERAL— SYLLOGISMS— THEIR DIVISIONS AC-
CORDING TO INTERNAL FORM.
Iw my last Lecture, I terminated the Doctrine of Judgments,
and now proceed to that of Reasonings.
"When the necessity of the junction or separation of a certain
subject-notion and a certain predicate notion is
•n,e act of reasoning ^^^ manifest from the nature of these notions
— what.
themselves ; but when, at the same time, we are
desirous of knowing whether they must be thought as inclusive, or
as exclusive of each other, — in this case, we find ourselves in a
state of doubt or indecision, from our ignorance of which of the
two contradictory predicates must be affirmed or denied of the sub-
ject. But this doubt can be dissipated, — this ignorance can be
removed, only in one way, — only by producing in us a necessity
to connect with, or disconnect from, the subject one of the re-
pugnant predicates. And since, ex hypothesis this necessity does
not — at least, does not immediately — arise from the simple knowl-
edge of the subject in itself, or of the predicate in itself, or of both
together in themselves, it follows that it must be derived from some
external source, — and derived it can only be, if derived, from some
other knowledge, which affords us, as its necessary consequence, the
removal of the doubt originally harbored. But if this knowledge
has for its necessary consequence the removal of the original doubt,
this knowledge must stand to the existing doubt in the relation of
a general rule ; and, as every rule is a judgment, it will constitute a
general proposition. But a general rule does not simply and of
itself reach to the removal of doubt and indecision ; there is re-
quired, and necessarily required, over and above this further knowl-
190 LOGIC. Lect. XV.
edge — that the rule has really an application, or, what is the same
thing, that the doubt really stands under the general proposition, as
a case which can be decided by it as by a general rule. But when
the general rule has been discovered, and when its application to
the doubt has likewise been recognized, the solution of the doubt
immediately follows, and therewith the determination of which of
the contradictory predicates must or must not be affirmed of the
subject; and this determination is accompanied with a conscious-
ness of necessity or absolute certainty." ' A simple example will
place the matter in a clearer light. When the
.u rat yanex- ^otion of the subject man is given alonw with
ample ^ "^ . ® '^
the contradictory predicates/rcc agent and neces-
sary agents there arises the doubt, with which of these contradic-
tory predicates the subject is to be connected ; for, as contradictoiy,
they cannot both be affirmed of the subject, and, as contradictory,
the one or the other must be so affirmed ; in other words, I doubt
whether man be a free agent or not. The notion man^ and the
repugnant notions free agent and necessary agenty do not, in them-
selves, affi^rd a solution of the doubt; and I must endeavor to dis-
cover some other notion which will enable me to decide. Now,
taking the predicate free agent, this leads me to the closely con-
nected notion moraUy responsible agent, which, let it be supposed
that I otherwise know to be necessarily a free agent, I thus obtain
the proposition. Every moraUy responsible agent is a free agent.
But this proposition does not of itself contain the solution of the
doubt ; for it may still be asked, Does the notion moraUy responsible
agent constitute a predicate which appertains to the notion of man,
the subject? This question is satisfied, if it is recognized that the
notion man involves in it the notion of a moraUy responsible agent,
I can then say, Man is a moraUy responsible agent. These two
propositions being thus formed and applied to the subsisting doubt,
the removal of this doubt follows of itself, and, in place of the
previous indecision, whether man be a free agent or not, there fol-
lows, with the consciousness of necessity or absolute certainty, the
connected judgment that Man is also a free agent. The whole
process — the whole series of judgments — will stand thus:
Every monjUy rtspongibU agmt it a free <tQeHt;
Man is a morally responsible. agent ;
Thenjore, man is a fret agent.
Let as consider in what relation the different constituent parts of
1 Bner, Lofikt ( 83, p. lU.
Lect. XV.
LOGIC.
191
The example given
is a Seasoning in the
whole of Extension,
i:ii<l may be repre-
sented by three circles.
this process stand to each other. It is evident that the whole pro-
cess consists of three notions and their mutual
relations. The three notions are, free agent,
responsible agent, and man. Their mutual rela-
tions are all those of whole and part, and whole
and part in the quantity of extension ; for the
notion free agent is seen to contain under it the
notion responsible agent, and the notion responsible agent to contain
under it the notion man. Thus, these three notions are like tliree
circles of three various extensions severally, contained one within
another ; and it is evident, that the process by which we recognize
that the narrowest notion, man, is contained under the widest
notion, responsible agent, is precisely the same by which we should
recognize the inmost circle to be contained in the outmost, if we
were only supposed to know the relation of these together by their
relation to the middle circle. Let ABC denote a
the three circles. Now, ex Jiypothesi, we know,
and only know, that A contains B, and that B con-
tains C ; but as it is a self-evident principle, that a
part of the part is a part of the whole, we cannot,
with our knowledge that B contains C, and is con-
tained in A, avoid recognizing that C is contained in A. This is
j)recisely the case with the three notions — free agent, responsible
agent, man ; not knowing the relation between the notions free
agent and man, but knowing that free agent contained under it
responsible agent, and that responsible agent contained under it
m,an, we, upon the principle that the part of a part is a part of the
whole, are compelled to think, as a necessary consequence, that
free agent contains under it man. It is thus evident, that the pro-
cess shown in the example adduced is a mere recognition of the
relation of three notions in the quantity of extension, — our knowl-
edge of the relation of two of these notions to each other being not
given immediately, but obtained through our knowledge of their
relation to the third.
But let us consider this process a little closer. The relations of
the three notions, in the above example, arc
those given in the quantity of Breadth or Ex-
tension. But every notion has not only an
Extensive, but likewise an Intensive, quantity,
— not only a quantity in breadth, but a quan-
tity in depth ; and these two quantities stand to
each other, as we have seen,^ always in a determinate ratio, — the
The reasoning of
Kxtension may be
exhibited in Compre-
hension — this illus-
trated.
1 See above, p. 104. — £d.
192 xoaio. L«cT. x\
ratio of inversion. It would, therefore, appear, a priori, to be a
necessary presumption, that if notions bear a certain relation to
each other in the one quantity, they must bear a counter relation to
each other in the other quantity ; consequently, that if we are able,
under the quantity of extension, to deduce from the relations ot
two notions to a third their relation to each other, a correspondent
evolution must be competent of the same notions, in the quantity
of comprehension. Let us try whether this theoretical presumption
bo warranted a posteriori, and by experiment, and whether, in tlie
example given, the process can be inverted, and the same result
obtained with the same necessity. That example, as in extension,
was :
AU responsible agents are free agents ;
But man is a responsible agent;
Therefore, man is a free agent.
in other words, — the notion responsible agent is contained under
the notion yVee agent; but the notion man is contained under the
notion responsible agent; therefore, on the principle that the part
of a part is a part of the whole, the notion man is also contained
under the notion /Vee agent. Now, on the general doctrine of the
relation of the two quantities, we must, if we would obtain the
same result in the comprehensive which is here obtained under tlio
extensive quantity, invert the whole process, that is, the notions
which in extension are wholes become in comprehension parts, an<l
the notions which in the former are parts, become in the latter
wholes. Thus the notion free agent, which, in the example given,
was the greatest whole, becomes, in the counter process, the small-
est part, and the notion man, which was the smallest part, now
becomes the greatest whole. The notion responsible agent remains
the middle quantity or notion in both, but its relation to the two
oth<?r notions is reversed ; what was formerly its part being now
its whole, what was formerly its whole being now its part. The
process will, therefore, be thus explicitly enounced :
The fiction man comprehends in it the notion responsible agent ;
But the notion responsible agent comfirebends in it the notion free agent ;
ThereforefOn the principle that the part of a part is a part tf the whole, tfie notion man
also comprehaids in it the notion free agent.
Or, in common language :
Mdfn is a responsible agent /
But a responsible agent is n firm ttgiM;
Thertfore, man is a free agent.
Lect. XV. LOGIC. 196
This reversed process, in the quantity of comprehension, gives, it is
evident, the same result as it gave in the quantity of extension.
For, on the supposition, that we did not immediately know that the
notion man comprehended free agent, but recognized that man
comprehended responsible agen% and that responsible agent com-
prehended free agent, we necessarily are compelled to think, in the
3vent of "his rec':gni':ion^ Lhat the nction m.a"^ comprehends the
notion free agent.
It is only necessary further to observe, that in the one process, —
that, to wit, in extension, the copula is, means is
The copula in ex- contained under, whereas, in the other, it means
tension and compre- comprehends hi. Thus the proposition, — G^orf
hension of a counter ./.t* t -i
meaning. ** mercxful, Viewed as m the one quantity, sig-
nifies God is contained under merciful, that is,
the notion God is contained under the notion merciful; viewed as
in the other, means, — God comprehends merciful, that is, the notion.
God comprehends in it the notion merciful.
Now, this process of thought (of which I have endeavored to
give you a general notion) is called Reasoning; but it has, like-
wise, obtained a variety of other designations. The definition of
this process, with its principal denominations, I shall include in the
following paragraph.
^ LIU. — Reasoning is an act of mediate comparison or
Judgment; for to reason is to recognize -
Par. Liii. Definition \^^2X two uotious Stand to cach othcr in the ■
of the process of i.. r. ■< •% -\ . t i
Keasoning, with the rclatiou ot a wholc and its parts, through
principal denomina- a rccognition, that thcsc notious severally
tions of process and . i..,i i.. . .i.-i/-^.
product. stand in the same relation to a third. Con-
sidered as an act. Reasoning, or Discourse
of Reason (to Xoyt^co-^ai, Xoywr/xo's, Siavota, to Siavoetcr^ai), is, likC'-
wise, called the act or process of Argumentation {argumenta-
tionis), of Ratiocination (ratiocinationis), of Inference or~
Illation (inferendi), of Collecting (colligendi), of Concluding:
(concludendi), of Syllogising {tov (rvAAoyt'^eor^ai, barbarously
syllogisandi). The term Reasoning is, likewise, given to the-
product of the act; and a reasoning in this sense (ratioci-
natio, ratiocinium), is, likewise, called an Argumentation-
{argumentatio) ; also, frequently, an Argument (argumentum)., ,
an Inference or Illation (illatio) ; a Collection (collectio), a
Conclusion {conclusion trvfnrepaafjM) ; and, finally, a Syllogism^
(crvXXoy «r/Aos) .
26
194 LOfiBIC. fjEcT. XT-
A. few words in explanation of these will suffice ; and, first, of
the thing and its definition, thereafter of its
Explicatioir.
names.
In regard to the act of Reasoning, nothing can be more eiToneous
than the ordinary distinction of this process, as
^^LThe Ai5t of Reas- ^j^^ operation of a faculty different in kind from
those of Judgment and Conception. Concep-
tion, Judgment, and Reasoning, are in reality only various applica-
tions of the same simple faculty, that of Comparison or Judgment.
I have endeavored to show that concepts are merely the results,
rendered permanent by language, of a previous process of compari-
.Hon ; that judgment is nothing but comparison, or the results of
comparison, in its immediate or simpler form ; and, finally, that reas-
oning is nothing but comparison in its mediate or more complex
application.^ It is, therefore, altogether erroneous to maintain^ as is
commonly done, that a reasoning or syllogism is
reason ng one ^ mere decompound whole, made up of judg-
organic whole. / . r j o
ments ; as a judgment is a compound whole,
made up of concepts* This is a mere mechanical mode of cleaving
the mental phenomena into parts ; and holds the same relation to a
genuine analysis of mind which the act of the butdier does to that
of the anatomist. It is true, indeed, that a syllogism can be sepa-
rated into three parts or propositions ; and that these propositions
have a certain meaning, when considered apart, and out of relation
to each other. But, when thus considered, they lose the whole sig-
nificance which they had when united in a reasoning; for their
whole significance consisted in their reciprocal relation, — in the
light which they mutually reflected on each other. We can cer-
tainly hew down an animal body into parts, and consider its mem-
bers apait ; but these, though not absolutely void of all meaning,
when viewed singly and out of relation to their whole, have lost the
principal and peculiar significance which they possesse<l as the coef-
ficients of a one organic and indivisible whole. It is the same with
a syllogism. The parts which, in their organic union, possessed life
and importance, when separated from each other remain only enun-
ciations of vague generalities, or of futile identities. Though, when
expressed in language, it be necessary to analyze a reasoning into
parts, and to state these parts one after another, it is not to be sup-
posed that in thought one notion, one proposition, is known before
or after another ; for, in consciousness, the three notions and their
reciprocal relations constitute only one identical and simultaneous
cognition.
1 6m above, pp. 88, 07. — ft>.
ElfcT. xt. to ore. f9S
The logicianis have indeed all treated the syllogisih as if this
were not the case. They have considered one
Error of logicians in proposition as naturally the last in expression,
their treatment of the S ,. , , . ,. , „ -, ,
Syllogism. ^^^ ^"^^ ^"^y have accordingly called the con-
cluHon; whilst the other two, as naturally goirig
before the other two, they have styled the premises^ forming to-
gether what they call the antecedent. The two premises they have
also considered as the one the greater (major)., the other the less
(minor), by exclusive reference to the one quantity of extension.
AH this, however, is, in my view, completely erroneous. For we
may, in the theory of Logic, as we actually do in its practical appli-
eationi5, indifferently enounce what is called the conclusion first dr
last. In the latter case, the conclusion forms a thesis, and the prem-
ises its groundis or reasons ; and instead of the inferential there-
fore (ergo, o^p°)i we would employ the explicative /br. The whole
diffbrence consists in this, — that the common order is synthetic,
the other analytic; and as, to express the thought, we must analyze
it, the analytic order of statement appears certainly the most direct
and natural.* On the subordinate matter of the order of the prertl-
ises, I do not here touch. ,
But to speak of thfe process in general : — without the power of
reasoning we should have been limited in our
II >o epiocess knowledge (if knowledge of such a limitation
of reasoning. o \ o
would deserve the name of knowledge at all),
— I say without reasoning we should have been limited to a knowl-
edge of what is given by immediate intuition; we should have been
unable to draw any inference from this knowledge, and have been
shut out from the discovery of that countless multitude of truths,
which, though of high, of paramount importance, are not self-evi#
dent. This faculty is, likewise, of peculiar utility, in order to pro-
tect us, in our cogitations, from eiTor and falsehood, and to removfe
these if they have already crept in. For every, the most complex,
web of thought may be reduced to simple syllogisms; and when
this is done, their truth or falsehood, at least in a logical relation,
flasiies at once into view.
Of the terms by which this process is denoiti-
2. Terms by which inated, Reasoning is a modification from the
the proce.8 of Reason- Preuch roisonn^r (and this a derivation from
ing 18 denominated. . *
the Latm ratio), and corresponds to ratioci?iatio,
cination. which has indeed been immediately transferred
iatd Out language under the form ratiocination.
Ratiocination denotes properly the process, but, improperly, also
1 ArisMtte^ Analytics are Bynthetie^
196 LOGIC. Lkct. XY.
the product of reasoning ; Jiatiocinium marks exclusively the pro-
duct. The oriffinal meaning of ratio was com-
Discoiirsc
putation, and, from the calculation of numbers,
it was transferred to the process of mediate comparison in general.
Discourse {discursus^ hiavota) indicates the operation of compari-
son, the running backwards and forwards between the characters or
no^es of objects -- {(^iscu-rerc inter notas, huur^wrBouL, : this *3nn
may, therefore, be properly applied to the Elaborative Faculty
in general, which I have just called the Discursive. The terms
discourse and discursics, Sidvoia, are, liowever, often, nay gen-
erally, used for the reasoning process, strictly considered, and dis-
imrsive is even applied to denote mediate, in opposition to intuitive,
judgment, as is done by Milton.^ The compound term, discourse
of reason^ unambiguously marks its employment in this sense.
Argumentation is derived from arffumentari,
rgumen a on. which means argttJnentis uti,' argument again,
argumentum,, — what is assumed in order to
argue something, — is properly the middle notion in a reasoning, —
that through which the conclusion is established ; and by the Latin
Rhetoricians it was defined, — "probabile inventum ad faciendam
fidem." ' It is often, however, applied as coextensive with argu-
mentation. Inference or illation (froui infero).
Inference. , ,, , "^ . . ,^ , "^ .
indicates the carrying out into the last proposi-
tion what was virtually contained in the antecedent judgments.
To conclude (concludere). again, signifies the
To conclude. „ ^ . -,,..,,
act of connecting and shutting into the last
proposition the two notions which stood apart in the two first. A
conclusion (conclusio) is usually taken, in its
Conclnsion. . . .'1 .
* Strict or proper signification, to mean the last
proposition of a reasoning ; it is sometimes, however, used to express
the product of the whole process. To syllogize means to form syllo-
gisms. Syllogism (trvXAoyw/io?) seems originally,
To Syllotrixe . ,., . t i ^ ..
SyiioKtem "^^ rotxo, to have denoted a computation — an
adding up — and, like the greater part of the
technical terms of Logic in general, was borrowed by Aristotle from
the mathematicians.* This primary meaning of these two words
J. I ftni^ut JLo*!, r. 486, — reason, aided with the inflaenee of dirine
" Whence thBioul grace." — Ed.
Raaion recelrea, and rctuon U her bclDK, ' Cicero, OnUoria PartitiomtM, G. 2. Cf. D'S-
;,! , Olscunivc or IntoitiTC; ditconne CMSIOIU, p. 149. — Ed.
Iione.tyoan."-ED. 4 [gee Piccartus, O^. Arist., pp. 4«7, 46*.
^ Shakspcare, Hamlet, act 1, so. 2,— Ammonins, In Qiiinqve Voces, f. 1. l'hn<^M>-
•' nns, /n jIk. Pn'of , f. li>. raciiu, />«. m (ky..
" * »*••*• "»•* '""'• dl»eouF«. of remMn. jjg ^^ Bcrtiug, Log. Perip. p. 119. Bat
Would hare mourned lonnr." nr i. ^ t no. ro i. < r •>.
^^ ••« Wait*, OrgoHon I. p. 884. [Schaln, LogOt,
Booker, S. F., ill. 8, 18 •> •' Bj diaoowM of t 70, p. lOL Ditctutitm*, p. 607, not*. -« Ed.]
Lkct. XV.
LOGIC. 1§^
favors the theory of those philosophers who, like Hobbes ^ and Lei-
denfrost,'' maintain that all thought is, in fact, at bottom only a cal-
culation, a reckoning. 2wAAoy«r/xos may, however, be considered as
expressing only what the composition of the word denotes, — a col-
lecting together; for <rvXA.oyi^£o-^at comes from oTjAAcyav, which signi-
fies to coUect? Finally, in Latin, a syllogism is
called collection and to reason coUigere. This
refers to the act of collecting, in the conclusion, the two notions
scattered in the premises.
. " From what has already been said touching the character of the
reasoning process, it is easy to see what are the
The general coiidi- , ,. . i • i n •
- ,, . general conditions which every syllogism sup-
tions of svllogism. o j j ts f
poses. For, as the essential nature of reasoning
consists in this, — that some doubt should be removed by the appli-
cation to it of some decisive general rule, there are to every syllo-
gism three, and only three, requisites necessary; 1°, A doubt, —
which of two contradictory predicates must be affirmed of a certain
subject, — the problem or question (problema, quaesitum) ; 2°, The
application of a decisive general rule to the doubt; and, 3°, The
general rule itself. But these requisites, when the syllogism is con-
structed and expressed, change their places ; so that the general rule
stands first, the application of it to the doubt stands second, and the
decision in regard to the doubt itself stands last. Each of these
necessary constituents of a syllogism forms by itself a distinct, though
a correlative, proposition ; every syllogism, therefore, contains three
propositions, and these three propositions, in their complement and
correlation, constitute the syllogism." * It will be proper, however,
here to dictate a paragraph, expressive of the denominations techni-
cally given to the parts, which proximately make up the syllogism.
^ LIV. A Reasoning or Syllogism is composed of two
parts, — that which determines or precedes, and that which
follows or is determined. The one is called the Antecedent
(anteceilens) ; the other, the Consequent (consequens). The
Antecedent comprises the two propositions, tlie one of which
^ Leviathan, Vt.\.c.b\ Computatio sive Log- avWoyifffJiSs . . . ws ffvWtyov rrjv ip
tea, c. 1. Cf. Stewart, EUments, P. ii. c. ii. § wa<rt tois opois Si«nrapfxeirqv dirdS*t|ij'!"
3; Works, vol. iii. p. 132 et seq. — Ed. Cf. Zabarella, In Anal. Post., 1. 1, Optra Log-
2 D-' Mfntr. Humana, c. viii. H 4, 10, pp. 112, tea, p. 640. "SfWoyKrixhi, non (rvWoyr) rwv
118, ed. 1793. — Ed. \6yeev, sed quasi avWoy^ rod \6yov, coUfrrirt
•"i Euirenios, AoyiKi], p. 405, et ibi Blemmi- rationii; ratio autem coUigi dicitur, dum ci,i.-
flae [Kcu rh fxey Syofia, on ffvWoyl] ris i<rr\ clusio infertur; quare a conclusione potiue,
\iyti)v •ir\ei6uoiv iv avrtf . . . 'O Se quam a propositionibus dictus est 8yllogi»
BAfjUjulS. iv ''Evirofi. Aoy. Ke<p. \d, "Tlori mus." — Ed.]
5« ;fol avrh rh vvivwipaa^ui KoKflToi {^pr^al) 4 Eager, Logik, \ 83, p. 166.
t^ hJOQW. Lect.XV.
enounces the general rule, and the other its application. These,
from their naturally preceding the conae-
na^uons^^'th^raru q"<^"*' »^® ^^^^^^ ^hc Frcmises {proposi-
which proximately tioncs proEmissce^ sumptio7ies^ membra atUe-
^nu ^^ ^^^ '^"° cedentia, Xi^/A/x«Ta). Of the premises, the
one which enounces the general rule, or the
relation of the greatest quantity to the lesser, is called the Major
Premise^ or Major Proposition^ or the Proposition simply
{propositio major^ propositio pHma^ proposition sumptuniy
sumptio major^ sumptio, thesis^ expositio, intentio, vpoakriii/K,
vporaais rj fiti^wv, Xijfifia to iiei^ov). The other premise, which
enounces the application of the general rule, or the relation of
the lesser quantity to the least, is called the Minor Premise^
the Minor Proposition^ the Assumptioiiy or the Subsumption
{propositio minor, propositio altera, assumptio, siibsumptuniy
SubsumptiOy sumptio minor, Trporaais ^ (Xd-n-wv, X^/i^a to tXarrov).
It is manifest that, in the counter qualities of Breadth and
Depth, the two premises will hold an opposite relation of
major and minor, of rule and application. The Consequent is
the final proposition, which enounces the decision, or the rela-
tion of the greatest quantity to the least, and is called the Con-
clusion (conclusio, conclusum, propositio condusc^, coUectiOy
complexio, summa, connexio, illatio, iyitentio, and, in Greek,
crvyxTT^cur/xo, to (rvvayoyifvov} ro cm^cpd/xevoi') . This part is usu-
ally designated by the conjunction Tlierefore {ergo. Spa), and
its synonyms. The conclusion is the Problem {problema)^
Question {qucBstio, qv^situm), which was originally asked,
stated now as a decision.' The problem is usually omitted
in the expression of a syllogism, but is one of its essential
parts. The whole nomenclature of the syllogistic parts, be it
observed, has reference to the one-sided views of the logicians
in regard to the process of reasoning.'
The Syllogism is divided into two parts, the
ExpiioaUon. Antecedent and the Consequent : — the autece-
Antecedent and . i i< >i ...
Consequent "^"^^ Comprehending the two propositions, in
which the middle notion is compared with the
two notions we would compare together; and the consequent com-
1 [Eugenics, AoyiKii passim.] [t. i., D* Censura Yeri, L. i\. p. (306 ft teg., ed.
« [Se6 Alex. AphrodisieiiRis, //> j4fio/. JVjor., 1556. — Ed.] Bachmann, Z.opiJt, p. 184. Fao-
V 0. 4, f. IV'. Boethius, In Topica Cictronis, 1. ciolati, Sextos Empiricu8. (Facciolati, Rii^i-
i , Opera, p. 764.] menta Logica, o. iii. p. 83, ed. 1750. Sextaa
S [See R. Agrioola, D* Invention* Dialeetita, Emplricua, HypotypoMS, L. ii. p. 86 *t aKbi. —
I., ii. 0. xir. pp. 401, 417, «». Tir^ Optra E|>.I
Lbct. XY. logic. 199
prising the one proposition, which explicitly enounces the relation
implicitly given in the prior of these two notious to each other.
The two propositions which constitute the antecedent are called,
among other names, the Premises. Of these,
the proposition expressing the relation of whole,
which one of the originally given notions holds to the assumed or
middle notion as its part, is called, among other appellations, the
Major Proposition, the Major Premise, or The
^°^' Pro2:)Osition, Kar i$6xrfv. The other proposition
of the antecedent enouncing the relation of whole, which the as-
sumed or middle notion holds to the other of the given notions as
its part is called, among other appellations, the Minor Proposi-
tion, the Minor Premise, the Assumption, or
the Suhsumption. These, as terms of relation,
vaj'y, of course, with the relation in the counter quantities. The
one proposition, which constitutes the consequent, is called, among
other appellations, the Conclusion. Perhaps the best names for
these three relative propositions of a syllogism
Sumption, subsump- ^^^^^ y^^ Sumption, Subsumjition, Conclusion,
tjon, and Conclusion. . ■' •* ^
as those which express, most briefly and natu-
rally, the nature and reciprocal dependence of the three judgments
of a syllogism. In the first place, the expressions Sumption and
SvhsumpAion are appropriate logical expres-
Grounds of their sions, in conscquence of their both showing
adoptionaBbestnames ^^^^ j^ogic Considers them, not as absolutely,
for the three proposi- '^ . . ''
tionsof asyiiogism. "ut Only as hvpothetically true ; for Logic does
not warrant the truth of the premises of a syl-
logism ; it only, on the supposition that these premises are true,
guarantees the legitimacy of the inference, — the necessity of the
conclusion. It is on this account that the premises have, by the
Greek logicians, been very properly styled Ai;^
/Aara,^ corresponding to the Latin snmptiones ;
and were there any necessity to resort to Greek, the Major Propo-
sition, which I would call Sumption (sumptio), might be well
denominated iemma simply; and the Minor Proposition, which I
would call the Subsumption (subsumpiio), might be well denomi-
nated the Hypolem.m,a. In the second place,
Hypolemma. i i i i • • i
though both premises are sumptions, or lem-
mata, yet the term sum,ption, as specially applied to the Major Prer
mise, is fully warranted both by precedent and principle. For, in
like manner, the major proposition — the major lemma — has always
I See Alexander, In Anal. Priori, C lA, h. Scholia, ed. Brsndis, p. 150. — Ed.
200 logic: Lect. xv.
obtained both from the Greek and Latin logicians the generic term ;
it has been called, The Proposition^ The Lemma {propositio, -fj irpo-
TOflTis, TO krjfxfia) ; and as this is the judgment which includes and
allows both the others, it is well entitled, as the principal proposi-
tion, to the style and title of the proposition^ the lemma, the sump-
tion by preeminence. In the third place, the term subsumption is
preferable to the term assumption^ as a denomi-
nation of the Minor Premise ; for the term
subsumption precisely marks out its relation of subordination to
the m.'ijor premise, whereas the term assumption does not. ^5-
tnimptton would indeed, in conti'ast to subsumption, have been an
unexce|)tionable word by which to designate the major proposition,
had it not been that logicians have very genenUly employed it to
designate the minor, so that to revei-se its application would be pro-
ductive of inevitable confusion. But for this objection, I should
certainly have preferred the term assumption to that of sumption^
for the appellation of the major proposition ; not that in itself it is
a preferable expression, but simply because assumption is a word
of familiar usage in the English language, which sum,ption and sub-
sumption certainly are not.
The preceding are reasons why the relative terms sumption and
subsumption ought to be employed, as being pos-
Objections to tiie itively good expressions ; but the expediency of
denominations of the ^j^^j^ adoption bccomcs Still moro manifest, when
Propositions of the i • i
Syllogism in ordinary "'^X ^^^ Compared and Contrasted with corre-
une. sponding denominations in ordinary use. For
M«jor Proposition j^g terms m^ojor proposition and major premise,
and Premise. Minor . ...-•.
p . . ^ , ., minor proposition and m.inor prem.ise, are cx-
mSte. posed to various objections. In the first place,
they are complex and tedious expressions, whereas
sumption and subsumption are simple and direct. In the second
place, the abbreviations in common use (the major proposition being
called the major, the minor proposition being called the minor) arc
ambiguous, not only in consequence of their vagueness in general, but
because there are two other parts of the syllogism to which these
expressions, tnajor and minor, may equally apply. For, as you will
soon be informed, the two notions which we compare together
through a third, are called the major and the minor terms of the
syllogism ; so that when we talk of majors and minors in reference
to a syllogism, it remains uncertain whether we employ th'?se words
to denote the propositions or the terms of a reasoning. Still more
objectionable are the correlative terms, Proposition and Assump-
tion, as synonyms for the major and minor premises. The term
Lect. XV. LOGIC. 201
proposition is a word in too constant employment in its vagne and
general sense, to be unambiguously used in a
iToposition. Assump- signification so precise and special as the one in
question ; and, in consequence of this ambigu-
ity, its employment in this signification has been in fact long very
generally abandoned. Again, the term assumption does not express
the distinctive peculiarity of the minor premise, — that of being a
subordinate proposition, — a proposition taken or assumed under
another ; this word would indeed, as I have noticed, have been ap-
plied with far greater propriety, had it been used to denote the major
in place of the minor premise of a syllogism.
These are among the reasons which have inclined me to employ,
at least along with the more ordinary denomina-
The use of Sumption tjons, the tcrms sumptiou and subsumption. Nor
and Subsumption sane- ... i i i • • t •
tioued by precedent. ^^ ^^ *« ^^ supposcd, that this usagc IS destitute
of precedent, for I could adduce in its favor even
the high authority of Boethius.^ In general and without reference to
Logic, it appears marvellous how, in English philosophy, we could so
long do without the noun subsumption, and the verb to sicbsume, for
these denote a relation which we have very frequently occasion to ex-
])ress, and to express which there are no other terms within our reach.
We have already in English assumption and assume, 2>^^sumption
and presum,e, consumption and consume, and there is no imaginable
reason why we should not likewise enrich the language,to say nothing
o^ sumption, by the analogous expressions subsumptioti.and subsume.
In regard to the proposition constituting the consequent of a
syllogism, the name which is generally bestowed
The Conclusion. * • , ^ t • • -,
on It, — the Conclusion, — is not exposed to any
serious objections. There is thus no reason why it should be super-
seded, and there is in fact no other term entitled to a preference.
So much in reference to the terms by which the proximate parts of
a syllogism are denoted. I now proceed to state to you in general
the Division of Syllogisms into Species determined by these parts,
and shall then proceed to consider these several species in detail.
But I have first of all to state to you a division of Syllogisms, which,
as comprehending, ought to precede all others. It is that of Syllo-
gisms into Extensive and Comprehensive.
% LV. The First Division of Syllogisms is taken from the
different kinds of quantity under which the reasoning proceeds.
I " Quoniam enim omniB Byllogismus ex «io." Boethios, De SyUogiamo Hypothetico, lib
prupositionibus texitur, prima vel propositio, i. — Ed.
vel sumptum vocatur; sccunda vero assump-
26
202 L-Q«i<;. Leot. XY.
For while every syllogism infers that the part of a part is a
part of the whole, it does this either iu the
Par. LV. First ©i- -^ . .
vision of Syllogisms quantity of Extension, — the Predicate of
into Extensive and ^jje two notions Compared in the Question
and Conclusion being the greatest whole, and
the Subject the smallest part ; or in the counter quantity of
Comprehension, — the Subject of these two notions being the
greatest whole, and the Predicate the smallest pait.
After what I have already stated in regard to the nature of these
opposite quantities, under the doctrine of Concepts and Judg-
ments,^ and after the illustrations I have given you of the possibility
of conducting any reasoning in either of these quantities at will,* —
every syllogism in the one quantity being convertible into a syllo-
gism absolutely equivalent in the other quantity, — it will be hero
needless to enlarge upon the nature of this distinction in general.
This distinction comprehends all others ; and its illustration, there-
fore, supposes that the nature of the various subordinate classes of
syllogisms should be previously understood. It will, therefore, be
expedient, not at present to enter on any distinct consideration of
this division of reasonings, but to show, when treating of syllogisms
under their various subaltern classes, how each is capable of being
cast in the mould of either quantity, and not, as logicians suppose,
in that of extensive quantity alone.
The next distinction of Syllogisms is to be sought for either in
the constituent elements of which they are corn-
Matter and form of :, . ^ , i • i . i
gyiio isms posed, or in the manner m which these are con-
nected. The former of these is technically called
the matter of a syllogism, the latter its form. You must, however,
observe that these terms are here used in a restricted meaning. Both
matter and form under this distinction are included in the form of ^
syllogism, when we speak of form in contrast to the empirical mat-
ter which it may contain. This, therefore, is a distinction under
that form with which Logic, as you know, is exclusively conversant ;
and the matter here spoken of should be called, for distinction's
sake, the formal or necessary matter of a syllogism. In this sense,
then, the matter of a syllogism means merely the propositions and
terms of which every syllogism is necessarily made up ; ' whereas,
1 See above, p. 100 tt seq. — Ed. " Materia (syllogiemi) alia est proxima, alia
2 See abovr, p 192 et sfrj. — Ed. remota. Reinota £uut termini propositionum,
8 Proxiipat.e pnd (cmotc matter. Marginal proxima vero sunt propositioiies ipsa, quibni
Jotting [Sec llurtudo dc yienAozs., Disput. coftlescit eyllogismuB." — Ed.]
riiil., Disp. Logita, t. i. d. x. § 48, p. 466.
Lkct. XV. LOGIC. 203
otherwise, the form of a syllogism points out the way in which these
constituents are connected.^ This being understood, I repeat that
the next distinction of syllogisms is to be sought for either in their
matter or in their form.
" Now in regard to their matter, syllogisms cannot differ, for every
syllogism, without exception, requires the same
Their form, the constituent parts, — a question, the subsumption
ground of the next ^^ j^ ^^^^^ ^ general rule, and the sumption of
grand distinction of /. • i
syllogisms. t^e general rule itself; which three constituents,
in the actual enunciation of a syllogism, change,
as I have already noticed, their relative situation;- — what was first
in the order of thought being last in the order of expression.
" The difference of Syllogisms can, therefore, only be sought for
in their different forms ; so that their distinc-
The form of Syllo- ^^^^g ^j.^ ^^^y formal. But the form of a syllo-
gism twofold, internal . . T T . ., ^ i T^ • r.
nd External g^s^n? Considered in its greatest generality, is oi a
twofold kind, viz., either an Internal and Essen-
tial, or an External and Accidental. The former of these depends
on the relations of the constituent parts of the syllogism to each
other, as determined by the nature of the thinking subject itself;
the latter of these depends on the external expression of the con-
stituent parts of the syllogism, whereby the terms and propositions
are variously determined in point of number, position, and consecu-
tion. We must, therefore, in conformity to the order of nature, first
of all, consider what classes of syllogism are given by their internal
or essential form ; and thereafter inquire what are the classes
afforded by their external or accidental modifications. First, then,
in regard to the Internal or Essential Form of Syllogism.
"A Syllogism is only a syllogism when the conclusion follows
from the premises with an absolute certainty ; and as this certainty
is determined by a universal and necessary law of thought, there
must, consequently, be as many kinds of Syllogism as there are
various kinds of premises affording a consequence in virtue of a
different law. Between the premises there is only one possible
order of dependency, for it is always the sumption, — the major
premise, which, as the foundation of the whole syllogism, must first
be taken into account. And in determining the difference of syl-
logisms, the sumption is the only premise which can be taken into
account as affording a difference of syllogism ; for the minor pre-
mise is merely the subsumption of the lesser quantity of the two
1 Krug, Logik, i 72, Anm., i. — Ed. [Cf. Fries, Logik, $ 44.] 3 Esser, L(^, i 85, p
159. — Ed.
204 LOGIC. Leci. X\
notions, concerning whose relation we inquire, under the question,
and this premise always appears in one and the same form, — in
that, namely, of a categorical proposition. The same is, likewise,
the case in regard to the conclusion, and, therefore, we can no more
look towards the conclusion for a determination of the diversity of
syllogism than towards the subsumption. We have thus only to
inquire in regard to the various possible kinds of major proposition."^
; Now as all sumptions are judgments, and as we have already
found that tlie most general division of judg-
y ogiems to ments, next to the primary distinction of in-
divided according to . *^ ^ "' .
the character of their tensive and extensive, is into simple and con-
sumptions and the law ditional, this division of judgments, which, when
regulating the connec- developed, affords the classes of rategorical, dis-
tion b«'tween premises . . , •, .• i t -, i.. t.
and conclusion. junctive, hypothetical, and hypothetico-disjunct-
ive propositions, will furnish us with all the
possible differences of major premises. " It is also manifest that in
any of these aforesaid propositions, — (categorical, disjunctive,
hypothetical, and hypothetico-disjunctive), — a decision of the ques-
tion, — which of two repugnant predicates belongs to a certain sub-
ject,— can be obtained according to a univereal and necessary law.
In a categorical sumption, this is competent through the laws of
Identity and Contradiction ; for what belongs or does not belong
to the superordinate notion, belongs or does not belong to the sub-
prdinate. In disjunctive sumptions, this is competent through the
law of Excluded Middle ; since of all the opposite determinations
one alone belongs to the object; so that if one isaflSrmed, the others
must be, conjunctively, denied ; and if one is denied, the others must
be, disjunctively at least, affirmed. In hypothetical sumptions, this
is competent through the law of Reason and Consequent ; for where
the reason is, there must be the consequent, and where the conse-
quent is, there must be the reason." - There are thus obtained three
or four great classes of Syllogisms, whose essential characteristics
I shall comprise in the following paragraph :
^ LVI. Syllogisms are divided into different classes, accord-
ing as the connection between the premises and conclusion is
1 Esscr, Logik, f 85. — £d. Baynes's Eaay on the ffnr Analytic of Logical
2 See Esser, Lo^ik, i 8C, p. 161. This clas- Forms, the author's later view is expressed as
sification of syllogisms cannot be regarded as follows : " All Mtdiatt inference is one — that
expressing the author's tinal view; according incorrectly called Cattgorical ,• for the Cm*
to which, as before observed, the principle of junctive and Disjunctive forms of Hypotkeiicti
Reason and Consequent is not admitted as a reasoning are reducible to immediate Infer-
Uw of thought. See above, p. 62, uotcl. In enccs." Compare Discussions, p. 661 wj. —
• note by Sir W. Hamilton, appended to Mr. Eo.
I.ECT. XV. LOGIC. 205
determined by the different fundamental laws, 1", of Identity
and Contradiction ; 2°, Of Excluded Mid-
^": .fT^ Tr^ die ; 3", Of Reason and Consequent ; these
grand division or Syl- ' ' ^ '
logisms - according Several determinations affording the three
to the law regulating dagses of CategoHcal, of Disjunctive, and
the laferenee. a ^ m
of Hypothetical Syllogisms. To these may
be added « fourth claRs, th--^ Hyp<thet^co-Hsjv^ctr:e o\ Dilerz-'
matic Syllogism, which is determined by the two last laws in
combination.
Before proceeding to a consideration of these several syllogisms
in detail, I shall, first of all, give you examples
Examples of the ^f ^j^g f^^^ species together, in order that you
four species of syllo- , i m ^ ^- c i, >. i ^
may have, while treating oi each, at least a
general notion of their differences and similarity.
gism.
1. Categorical. 1. — Of a Categorical Syllogism.
Sumption, AH matter is created ;
Sabsnmption, .... But the heavenly bodies are material ;
Conclusion Therefore, the heavenly bodies are created.
2. DisJanctiTO. 2. —Of a Dibjtjnctivb Stllooism.
Sumption, The hope of immortality is either a rational expectation or an illusion f
Subsumption, . . . But the hope of immortality is a rational expectation;
Conclusion, .... Therefore, the hope of immortality is not an illusion.
3. Hypothetical. 3. — Of an Htpothktical Syllogism.
Sumption If Logic does not profess to be an instrument of invention, the r^roack
that it discovers nothing is unfounded ;
Subsumption, . . . But Logic does not profess to be an instrument of invention ;
Conclusion, .... Therefore, the reproach that it discovers nothing is unfounded.
4. Hypothetico-dis- 4. — Of the Dilemma ok Hypothetico-disjunctivb
junctive. Syllogism.
Sumption, If man were suited to live out of society, he would either be a god or a
beast;
Subsumption, . . . But man is neither a god nor a beast;
Conclusion, .... Therefore, he is not suited to live out of society.
LECTURE XVI.
STOIOHErOLOG-Y.
SECTION II.— OF THE PRODUCTS OF THOUGHT
ni— DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO INTERNAL
FORM.
A. SIMPLE —CATEGORICAL. — L DEDUCTIVE IN EXTENSION.
In our last Lecture, I entered on the Division of Syllogisms. I
first stated to you the principles on which this
ecap na on. division must proceed; I then explained the
nature of the first great distribution of Reasonings into those of
Intensive and those of Extensive Quantity; and, thereafter, that of
the second great distribution of reasonings into Simple and Condi-
tional, the Simple containing a single species, — the Categorical ;
the Conditional comprising three species, — the Disjunctive, the
ttypothetical^ and Hypothetico-disjunctive.^ These four species
I showed you, were severally determined by different fundamental
Laws of Thought : the Categorical reposing on the laws of Identity
and Contradiction ; the Disjunctive on thij law of Excluded Middle ;
the Hypothetical on the law of Reason and Consequent ; and the
Hypothetico-disjunctive on the laws of Excluded Middle and Rea-
son and Consequent in combination.
I now go on to the special consideration of the first of these
classes of Syllogism — viz., the Syllogism which
. mpe y ogsm. has been denominated Categorical. And in re-
The Categorical. ^ , ^
gard to the meaning and history of the term cat-
egorical, it will not be necessary to say anything in addition to what
1 Compare above, p. 187 Gi><
r^ECT. XVI. LOGIC. 207
I have already stated in speaking of judgments.^ As used originally
by Aristotle, the term categorical meant merely affirmative^ and
was opposed to negative. By Theophrastus it was employed in the
sense absolute, — simple, — direct, and as opposed
The term Categorical. - . , j • ^u- '•£-.• •. i
to conditional ; and m this signincation it has
continued to be employed by all subsequent logicians, without
their having been aware that Aristotle never employed it in the
meaning in which alone they used it.
% LVII. A Categorical Syllogism is a reasoning whose form
is determined by the laws of Identity and
Par. Lvn. The Gate- Contradiction, and whosc sumption is thus
gorioal Syllogism.— . . , t r^ • ,
what. a categorical proposition^ In a Categorical
Syllogism there are three principal notions,
holding to each other the relation of whole and part ; and these
are so combined together, that they constitute three proposi-
tions, in which each principal notion occurs twice. These
notions are called Terms {termini^ opot), and according as the
notion is the greatest, the greater, or the least, it is called the
Major, the Middle, or the Minor Term.^ The Middle Term is
called the Argument (argumentum, Aoyo?, iriarts); the Major
and Minor Terms are called Extremes (extrema, a/cpa). If the
syllogism proceed in the quantity of Extension (and this form
alone has been considered by logicians), the predicate of the
conclusion is the greatest whole, and, consequently, the Major
Tenii ; the subject of the conclusion, the smallest part, and,
consequently, the Minor Term. If the syllogism proceed in
the quantity of Comprehension, the subject of the conclusion
is the greatest whole, and, consequently, the Major Term; the
predicate of the conclusion, the smallest part, and, consequently,
the Minor Term. In either quantity, the proposition in which
the relation of the major term to the middle is expressed, is the
Sumption or Major Premise, and the proposition in which is
expressed the relation of the middle term to the minor, is the
Siihsumption or Minor Premise. The general forms of a Cate-
gorical Syllogism under the two quantities, are, consequently,
the following:
1 See above, p. 165 fi «?. — Ed. L. vi. c. xii. p. 343. Hnrtado de Mendoza, p.
2 [On principle of name of Major and Ml- 469.] [Disp'ut. Fhilosophicce, t. i. ; Disp. Logicce,
nor terms, see Alex. Aphrodisiensis, In An. d. x. } 50 et seg. TolosjB, 1617. See also JW*
Prior., L. i. CO. iv. v. Fliiloponus, In An. eussions, p. 66Q et seq. — Ed.]
Prior., L. i. f 23 b. Fonseca, Instit. Dialect.,
208 LOGIC. Lkct. XVL
t
AH JEXTENSIVB STI.LOaiSlC. AN IlfTKNSIVK STUXXUSM.
BisA CtsB
C is B B t s A
Ct«A CtsA
AH man is mortal ; Caius is a man ;
But Caius is a man ; Bui all man is mortal;
Therefore, Caius is mortal. Therefore, Caius is nortaL
In these examples, you are aware, from what has previously been
said,' that the copula in the two different quan-
£xplication. . . • ^ • i
titles 18 precisely of a counter meaning ; in the
quantity of extension, signifying contained under; in the quantity
of comprehension, signifying contains in it. Thus, taking the sev-
eral formulae, the Extensive Syllogism will, when explicitly enounced,
be as follows :
The Middle term B is contained under the Major term A;
Example of the Ex- ^^ ^^ ^^.^^ term C is contained under the Middle term B ;
tensive Categorical
Svlloeism There/ore, the Minor term C is also contained under the Major
term A.
Or, to take the concrete example :
The Middle term aU men is contained under the Major termmortal;
But the Minor term Caius is contained under the Middle term all men ;
Ther^ore, the Minor term Caius is also contained under the Major term mortal.
On the contrary the Intensive Syllogism, when
Of the Intensive. ,. , . ^ „ J o "»
explicated, is as follows :
The Major term C contains in it the Middle term B;
But the Middle term B contains in it the Minor term A ;
Therefore, the Major term C also contains in it the Minor term A.
Or, in the concrete example :
The Major term Caius contains in it the Middle term man ;
But the Middle term man contains in it the Minor term mortal ;
Thertfore, the Major term Ccuus also contains in it the Minor term mortal.
Thus you see that by revereing the order of the two premises,
and by reversing the meaning of the copula, we can always change
a categorical syllogism of the one quantity into a categorical syllo-
gism of the other.*
1 See above, p. 198. — Kd.
s Mot in Inductive S^rllogisms. Jauing. [See below, p. 228. — Ed.]
Lect. XVI. LOGIC. 209
In this paragraph is enounced the general nature of a categorical
syllogism, as competent in both the quantities of extension and
comprehension, or, with more propriety, of comprehension and ex-
tension ; for comprehension, as prior to extension in the order of
nature and knowledge ought to stand first. But as all logicians,
with the doubtful exception of Aristotle, have limited their consid-
eration to that process of reasoning given in the quantity of exten-
sion, to the exclusion of that given in the quantity of comprehension,
it will be proper, in order to avoid misapprehension, to place some
of the distinctions expressed in this paragraph in a still more
explicit contrast.
In the reasonings under both quantities, the words expressive of
the relations and of the things related are identi-
The reasoning in cal. The things Compared in both quantities
comprehension and ^^^ ^^^ ^^^^ j^ ^^^^^^.^ ^^^ ^^ number. In each
that in Extension ex- .
pHcitiy compared and there are three notions, three terms, and three
contrasted. propositions, combined in the same complexity ;
and, in each quantity, the same subordination of
a greatest, a greater, and a least. The same relatives and the same
relations are found in both quantities. But though the relations and
the relatives be the same, the relatives have changed relations. For
while the relation between whole and part is the one uniform rela-
tion in both quantities, and while this relation is thrice realized in
each between the same terms ; yet, the term which in the one quan-
tity was the least, is in the other the greatest, and the term which in
both is intermediate, is in the one quantity contained by the term
which in the other it contained.
Now, you are to observe that logicians, looking only to the reason-
ing competent under the quantity of extension.
Narrow and errone- and, therefore, looking only to the possibility of
ous definitions by lo- a single relation between the notions or terms
gicians of the Major, f ^^ • ^ • n -i •
Middle, and Minor ^f a Syllogism, have, m consequence of this one-
terms, sided consideration of the subject, given defini- -
tions of these relatives, which are true only
when limited to the kind of reasoning which they exclusively con-
templated. This is seen in their definitions of the Major, Middle^
and Minor Terms.
In regard to the first, they all simply define the Major term to be
the predicate of the conclusion. This is true of
1. Mfljor. ^ .
the reasoning under extension, but of that ex-
clusively. For the Major term, that is, the term which contains-
both the others — in the reasoning of comprehension, is the subject
of the conclusion. Again, the Minor term they all simply define to-
27
2X0 LQ&ia. Lkct. XVI
be th& subject of the conclusion ; and thia is likewise true only of
the reasoning under extension : for, in the reasour
2. Minor. . ,,.,,,■ • ,
ing under comprehension, the Minor teirin is the
predicate of the conclusion. Finally, they all simply define the
Middle term as that which is contained under the predicate, an4
contains under it the subject of the conclusion.
3. Middle. ,.,„.. ,.i ,
x>ut this definition, like those of the two other
terms, must be reversed as applied to the reasoning under comprehen-
sion. I have been thus tediously expUcit, in order that you should
be fully aware of the contrast of the doctrine I propose, to what you
will find in logical books ; and that you may be prepared for the
further development of this doctrine, — for its application in detail.
In regard to the nomenclature of the Major, Minor, and Middle
terms, it is not necessary to say much. The
Nomenclature of Ma- expression term (temiinuSy opos), was first em-
term* '"""^ "* * ployed by Aristotle, and, Hke the greater part
of his logical vocabulary, was, as I have observed,
borrowed from the language of Mathematics.^ You are aware that
the word term is applied to the ultimate constituents both of propo>-
sitlons and of syllogisms. The terms of a proposition are the
subject and predicate. The terms of a syllogism are the three
notions which in their threefi)ld( combination form the three puopo-
sitions of a syllogism. The major and minor
Arirtotie's definition terms Aristotle, by another mathematical nieta-
ofthc termsofasyllo- , n .i ^ /• \ ^i • j
^^^ phor, calls the extremes {aLKpa)y the fnc^or and
m,mor extremes/ and his definition of these and
of the middle term is, unlike those of the subsequent logicians, so
general, that it will apply with perfect propriety to a syllogism in
either quantity. " I call," he says, " the middle term that which is
both itself in another and another in it ; and which, by its position,
lies in the middle ; the extremes I call both that which is in another
and that in which another is." * And in another place ho says, "I define
the major extreme that in which the middle is j the minor extreme
that which is subordinated to the middle."'
I may notice that the part of his definitioa of
Hi« definition of the ^^^ middle term, where he describes it as " that
Middle term, as mid- . • ^ ^^ n n
die by position, not whicli, by its position, lios in the middle, does not
applicable to tiiemode apply to the modc in which subsequent logicians
in which subsequent enounce the syllogism. For let A be the major,
loiriclans enounce the ni .i-n -ii-ii • . f i-i
syiioirinik ^ ^"^ middle, and C the minor term of an Kx
tensive Syllogism, this will be expressed Uius:
V See Scheibler, [Opera Logica, Para. iii. o. 2, > ^mi^. Prior.. L. i., o. i, f 4.
V 898, and abore, p. 19G, note 4. —Ed.] » Ibid., ^ 8.
I
Samptionv B'rts.A,i.«. Bi is mntained anderA.
Snbsuraptibn,. . . . C is B", i. e. € is oontcdned under B.
Conclusion, . . . . . C t» A, t. c. C is also contained under A.
In this syllogism the middle term B stands first and last in the
premises, and, therefore, Aristotle's definition
But quite applicable ^^ ^^^ ^^j^^j^ ^ ^^^ ^^j ^^ ^j^^j^ ^ ^^^
to (he reasoning in ...
Comprehension. ture, containing the minor and contained by
the major, but as middle by position, standing
after the major and before the minor, becomes inept. It will apply,
however, completely to the reasoning in comprehension ; for the
extensive syllogism given above being converted into an intensive,
by reversing the two premises, it will stand as follows :
Sumption, C w B,,t. e. C omtUdna in it B.
Subsumption,. ... B is A, t. e. B contains in it A.
Ck>ndusion, C is A, i. c. C also contains in it A. '
It does not follow, however, from this, that Aristotle either
contemplated exclusively the reasoning in comm-
it does not, however, \ " '^
follow that Aristotle prehension, or that he contemplated the reason-
contemplated exciu- ings in both quantities: for it is very easy to
siveiy the reasoning state a reasoning in extension, so that the major
pre nsion. term shall stand first, the middle term second^
and the minor last. We can state it thus :
Sumption, A is B, i. e. A contains under it B.
Subsumption,. . . . B is C, t. e. B contains under it C.
Conclusion, A is C, i. e. A contains under it C.
This is as good a syllogism in extension as the first, though it is
not stated in the mode usual to logicians. We may also convert iiB
into a comprehensive syllogism, by reversing its premises and the
meaning of the copula, though here also the mode of expression will
be unusual :
Sumption, B is C, i. c. B is contained in C.
Subsumption,. ... A is B, t. e. A is contained in B.
Conclusion, A is C, i. c. A is contained in C.
From this you will see, that it is not to the mere external
arrangement of the terms, but to the nature of their relation, that
we must look in determining the character of the syllogism.
Before leaving the consideration of the terms of a syllogism, I
may notice that the most conA'enient mode of stating a syllogism in
212
LOGIC.
Lkct. XVI
Most convenient
mode of stating a syl-
logism in an abstract
form.
Categorical Syllo-
gisms divided into
special classes accord-
ing to the applications
of the laws of Iden-
tity and Contradiction
under the relation of
whole and part-
an abstract form, is by the letters S, P, and M, — S signifying tbo
subject, as P the predicate, of the conclusion,
and M the middle term of the syllogism. This
you will b§ pleased to recollect, as we shall
find it necessary to employ this notation in
showing the differences of syllogisms from the
different arrangement of their terms.
I have formerly stated that categorical syllogisms are regulated
by the fundamental laws of Identity ^nd Con-
tradiction; the law of Identity regulating Af-
firmative, the law of Contradiction, Negative,
Categoricals. As, however, the laws of Iden-
tity and Contradiction are capable of certain
special applications, these will afford the ground
of a division of Categorical Syllogisms into a
corresponding number of classes. It has been
already stated, that all reasoning is under the relation of whole and
part, and, consequently, the laws of Identity and Contradiction
will find their application to categorical syllogisms only under this
relation.
But the relation of whole and part may be regarded in two pointa
of view ; for we may either look from the whole
to the parts, or look from the parts to the whole.
This being the case, may we not apply the prin-
ciples of Identity and Contradiction in such a
way that we either reason from the whole to
the parts, or from the parts towards the whole ?
Let us consider : looking at the whole and the
parts together on the principle of Identity, we are assured that the
whole and all its parts are one, — that whatever is true of the
one is true of the other, — that they are only different expressions
for the different aspects in which we may contemplate what in itself
is absolutely identical. On the principle, therefore, that the whole
is only the sum of the parts, I am entitled, on the one hand, looking
from the whole to its parts, to say with absolute certainty, — What
belongs to a whole belongs to its part; and what does not belong
to a whole does not belong to its part : and on the other, looking
from the parts to their whole, to say, — "What makes up all the parts
constitutes the whole ; and what does not make up all the parts
does not constitute the whole. Now, these two applications of the
principles of Identity and Contradiction, as we look from one term
of the relation of whole and part, or from the other, determine two
different kinds of reasoning. For if we reason downwards, from
The relation of
whole and part may
be regarded in two
pointa of view, and
thus affords two class-
es of Reasonings.
Lect.xvl logic. 218
a containing whole to a contained part, we shall have one sort of
reasoning which is called the Deductive; whereas, if we reason up-
wards, from the constituent parts to a constituted whole, we shall
have another sort of reasoning, which is called the Inductive. This
I shall briefly express in the following paragraph.
% LVIII. — Categorical Syllogisms are Deductive^ if, on
the principles of Identity and Contradic-
P»r. LVIlI. Categor. , * ' •'
icai Syllogisms di- tion, WO rcason downwards, from a con-
•■ vided into Deductive taining wholc to a contained part; they
and Inductive. t-^ t . •/• • • /
are Inductive^ ii, on these pnnciples, we
reason upwards, from the constituent parts to a constituted
whole.
This is sufficient at present to afford you a general conception
of the difference of Deductive and Inductive
. ,."f, "^ * *" Categoricals. The difference of these two kinds
gorical Syllogisms. ^ . .
of reasoning will be properly explained, when,
after having expounded the nature of the former, we proceed to
consider the nature of the latter. We shall now, therefore, con-
sider the character of the deductive process, — the process which
has been certainly and most successfully analyzed by logicians ; for,
though their treatment of deductive reasoning has been one-sided
and imperfect, it is not positively erroneous; whereas, their analy-
sis of the inductive process is at once meagre and incorrect. And,
first, of the proximate canons by which Deductive Categoricals
ive regulated.
T LIX. In Deductive Categoricals the universal laws of
Identity and Contradiction take two modi-
Par. LIX. Deductive fied forms, accordiug as these syllogisms
Categoricals, — their i . i • f r-i i •
proceed in the quantity oi Comprehension or
canons.
in that of Extension. The peculiar canon
by which Intensive Syllogisms of this class are regulated, is, —
What belongs to the predicate belongs also to the subject;
what is repugnant to the predicate is repugnant also to the
subject. The peculiar canon by which Extensive Syllogisms
of this class are regulated is, — What belongs to the genus
belongs to the species and individual; what is repugnant to
the genus is repugnant to the species and individual. O:-,
more briefly. What pertains to the higher class pertains also
to the lower.
214
LOGIC.
Lect. X¥I
Both these laws are enounced by Aristotle,* and both, from hi™^
have passed into the writings of subsequent logicians. The former,
as usually expressed, is, — JPrmdicatutn prcth
dicati est etiam prcBdicatum subjecti; or, Nota
notce est etiam nota rei ipsius. The latter is correspondent to what
is called the Dicta de Omni et de Nvllo; the Dictum de Omniy
when least ambiguously expressed, being, — Quicquid de omni
valet, valet etiam de quibusdem, et singidus; — and tlie Dictum de
Nulla being, — Quicquid de nuUo valet ^ nee de quibusdam nee do
singulis valet. But as logicians have altogether overlooked tho
reasoning in Comprehension, they have, consequently, not perceived
the proper apphcation of tl>e former canon ; which, therefore, re-
mained in their systems either a mere hors d\euvre, or else was
only forced into an unnatural connection with the principle of the
syllogism of extension.
Before stating to you how the preceding canons are again, in
their proximate application to categorical syllo-
gisms, for convenience sake, still more explicitly
enounced in certain special rules, it will be
proper to show you the method of marking the
connection of the propositions and terms of a
categorical syllogism by sensible symbols. Of
these there are various kinds, but, as I formerly noticed, the best
upon the whole, because the simplest, is that by circles.* Accord-
ing to this method, syllogisms with affirmative and negative con-
dosions would be thus represented.'
Connection of the
propositions and terms
of tlie Categorical Syl-
logism illustrated by
sensible symbols.
Ext.
Int.
AFFIRMATIVE.
Int.
S-
Ext.
-P
-M
-M
1 Categ.. C 8. Anal. Prior., 1. 1. —Ed.
* [An objection to the mode of syllojfistio
notation by circles is, that \\c cannot, by this
mode, show that the contained exhausts the
containing; for we cannot divide the area of
n circle between any number of contained
circles, representing in extension all ooUrdJ-
nate species, in oomprehensioa all the imme-
diate attributes] [For the author's fiiml
scheme of notation, sec Tabular Scheme : t
end of volume. — Ed.]
3 See above, p. 180. C£ Krng Logik, i 1^
p. 245. — Eo.
LKicr. ;XVL
LOGIC.
Proximate Rules of
Categorical Syllo-
gisms. 1. Extensive.
You are now prepared for the statement and illustration of the
various proximate rules by which all categorical
syllogisms are regulated. And, first, in regard
to these rules in relation to the reasoning of
Extension.
" Aldrich," says Dr. Whately, " has given twelve rules, which I
find might be more conveniently reduced to six. No syllogism can
be faulty which violates none of these rules." ^ This reduction of
the syllogistic rules to six is not original to Dr. Whately ; but had
he looked a little closer into the matter, he might have seen that the
six which he and other logicians enumerate, may, without any sac-
rifice of precision, and with even an increase of perspicuity, be
reduced to three. I shall state these in a paragraph, and then illus-
trate them in detail.
^ ^^ ^ ^ H LX. An Extensive Categorical Syllo-
Par. IiX. The Three " ^ o j
Buies of the Exten- gism, if regularly and fully expressed, is
sive Categorical syi- governed by the three following rules :
I. It must have three, and only three,
Terms, constituting three, and only three, Propositions.
II. Of the premises, the Sumption must in quantity be
Definite (i. e. universal or singular), and the Subsumption in
quality Afiirmative.
III. The Conclusion must correspond in Quantity with tibe
Subsumption, and in Quality with the Sumption.^
1 Elements ofLogik,B. ii. c. iii. } 2, p. 85, 8th
edit. — Ed.
2 Krug, Logik, § 80. — Ed. [Cf. Alexander
Aphrodisieusis, In An. Prior., L. I., f. 17, Aid.
Derodon, Logica Restituta, p. 639 et seg, Hoff-
bauer, Anfangsgriinde der Logik, S 317, p. 164.
Bachmann, Logik, i 122, p. 187. Esser, Logik,
H 88, 89. Schulze, Logik, } 79. Fries, LogU^
i55,p..224.]
216 LOGIC. Lect^ XVL
These three simple laws comprise all the rules which logicians
lay down with so confusing a minuteness.' The
inurtration. Firet firgt is : — A Categorical syllogism, if regular and
perfect, must have three, and only three, prop-
ositions, made up of three, and only three, terms. "The necessity
of this rule is manifest from the very notion of a categoiical syllo-
gism. In a categorical syllogism the relation of two notions to each
other is determined through their relation to a third ; and, conse-
(jnently, ench must be compared once with the intermediate notion,
and once with each other. It is thus manifest that there must be
three, and cannot possibly be more than three, terms ; and that
these three terms must in their threefold comparison, constitute
three, and only three, propositions. It is, however, to be observed,
that it may often happen as if, in a valid syllo-
What is properly to -^^ ^j^^.^.g ^^j.g ^^^.g ^^^^ ^^iree principal no-
be regarded as a logi- . , t-> • i i
^ jgj^ tions, — three terms. Uut, in that case, the tenns
or notions are only complex, and expressed by a
plurality of words. Hence it is, that each several notion extant in
a syllogism, and denoted by a separate word, is not on that account
to be viewed as a logical term or terminus, but only those which,
either singly or in connection with others, constitute a principal
momentum of the syllogism." ' Thus, in the following syllogism,
there are many more than three several notions expressed by three
several words, but these, we shall find, constitute in reality only
three principal notions or logical terms :
Samption He who conscientiously performs his duty is a truly good man ;
Subsumption . . . Socrates consrietitiously performs his duty;
Conclusion Therefore, Socrates is a truly good man.
Here there are in all seven several notions denoted by seven sep-
arate words: — 1. Conscientiously, 2. Performs, 3. Duty, 4, Truly,
5. Good, 6. Man, 7. Socrates ^ but only three principal notions or
logical terms, — viz., 1. Conscientiously performs his duty, 2. Truly
good m.an, 3. Socrates.
"When, on the other hand, the expression of the middle term in
the sumption and subsumption is used in two
Significations, there may, in that case, appear to
be only three terms, while there are in reality four ; or as it is tech-
nically styled in logic, a quaternio term,inorum.^ On this account,
1 See Scheibler, Opera Logica, pars, iv., p. S Kmg, Logik, ( 80, p. 246. Anm. 1. — Rd
516. Keckermann, Systema Logica Minus, S [Cf. Fonseoa, [/luitt. Dial., L. rL c. 20, p
Oi>ro. t. i., p. 239. — Ed. 869. — £d.]
I
lect. xvl logic. 217
ihe syllogism is vicious in point of form, and, consequently, can
afford no inference, howbeit that the several propositions may, in
point of matter, be all true. And why ? — because there is here no
mediation, consequently no connection between the different terms
of the syllogism. For example :
The animals are void of reaaon;
Man is an animal ;
Therefore, man is void of reason.
" Here the conclusion is invalid, though each proposition, by itself,
and in a certain sense, may be true. For here the middle term, ani-
mal, is not taken in the same meaning in the major and minor prop-
ositions. For in the former, it is taken in a narrower signification,
as convertible with brute, in the latter in a wider signification, as
convertible with animated organism.''^ ^
The second rule is: — Of the premises, the sumption must in
quantity be definite (universal or singular), the
subsumption must in quality be affirmative. —
The sumption must in reference to its quantity be definite ; because
it affords the general rule of the syllogism. For if it were indefi-
nite, that is, particular, we should have no security that the middle
terra in the subsumption comprised the same part of the sphere
which it comprised in the sumption. p
Thus: ^^ ^
Some M are P; S
^nSar«P;
AU S are P. /""'m'^N.
Or, in a concrete example :
Some tvorks of art are cubical;
AU pictures are vxrrks of art ;
Therefore, all pictures are cubical ;
kJl)
In regard to the subsumption, this is necessarily affirmative. The
sumption is not limited to either quality, because the proposition
enouncing a general rule may indifferently declare All M is P, and
No M is P. The assumption is thus indeterminate in regard to
quality. But not so the proposition enouncing the application of a
general rule. For it must subsume, that is, it must affirm, that
something is contained under a condition ; and is, therefore, neces-
sarily affirmative. We must say S is M. But in respect of quantity
I Knig, LogiU. p. 247. —Ed.
28
218 LOGIC* Lkct. XVi.
it is undetermined, for we can either say All S is M, or Some S is
M. If the subsumption is negative, there is no inference; for it ia
not necessary that a genus should contain only things of a certain
species. This is shown in the following example :
All men are animals;
N» horse is a man ;
Therrfore, no hone is cm ammaL
Or, as abstractly expressed :
AUMaref;
But no S IS II;
JVoStsP.
Thus it is, that in a regular extensive categorical syllogism, the
sumption must be always definite in quantity, the subsumption
always affirmative in quality.^
I have, however, to add an observation requisite to prevent the
possibility of a misconception. In stating it as
Misconception in re- ^ ,.^lg ^f exrtensive categoricals, that the sump-
gard to definiteness of ^. ^ \ i u •, / ■ i • i\'^
sfmption m second ^^^^ ™"«* ^^ defanite (universal or singular), if
rnie obviated. you are at all conversant with logical books, you
will have noticed that this rule is not in unison
with the doctrine therein taught, and you may, accordingly, be sur-
prised that I should enounce as a general rule what is apparently
contradicted by the fact that there are syllogisms — valid syllo-
gisms — of various forms, in which the sumption is a particular, or
the subsumption a negative, proposition. In explanation of this, it
is enough at present to say, that in these syllogisms the premises
are transposed in the €X}5ression. You will, hereafter, find that the
sumption is not always the proposition which stands first in the
enunciation, as the conclusion is not always the
The mere order of proposition wliich Stands last. Such Iransposi-
enunciation does not tions are, however, only external accidents, and
constitute the sump- ,i i • i_ • i_ ^i_ • j
. ,. the mere order in which the premises and oon-
tion or subsumption , ^
in a reasoning. clusion of a Syllogism are enounced, no moru
changes their nature and their necessary relation
to each other, than does the mere order in which the grammatical
parts of a sentence are expressed, alter their essential character and
reciprocal dependence. In the phrases- vir bonus and bonus vir, — •
iu both, the vir is a substantive and the bonus an adjective. In the
1 Krug, Logik, f2iS Bachmaon, LoiUc, i 124. — Ed.
Lect XVL logic. 219
sentence variously enounced, — Alexander Ikirvum vicit^ — Alexanr-
der vicit Darium, — Dariwm Alexander vicit^ — Darium vicit Alex-
ander ^ — Vicit Alexander Daritian, — Vicit Darium Alexander: —
in these, a difference of order may denote a difference of the inter-
est we feel in the various constituent notions, but no difference of
tbeir grammatical or logical relations. It is the same with syllo-
gisms. The mere order of enunciation does not
What truly consti- change a sumption into a subsumption, nor a
tutes the sumption and , .• • j. ^' t^ • ^t_ •
. ,. , subsumption into a sumption. It is their essen-
subsumption in a rea- ^ ^ ^ ^ ^
goning. tial relation and correlation in thought which
constitutes the one proposition a major, and the
other a minor premise. If the former precede the latter in the
expression of the reasoning, the syllogism is technically regular; if
the latter precede the former, it is technically irregular or trans-
posed. This, however, as you will hereafter more fully see, has not
been attended to by logicians, and in consequence of their looking
away from the internal and necessary consecution of the premises
to their merely external and accidental arrangement, the science
had been deformed and perplexed by the recognition of a multi-
tude of different forms, as real and distinct, which exist only, and
are only distinguished, by certain fortuitous accidents of expres-
sion. This being understood, you will not marvel at the rule in
regai'd to the quantity of sumptions in extensive syllogisms (which,
however, I limited to those that were regularly and fully expressed),
— that it must be definite. Nor will you marvel at the counter
canon in regard to the quality of sumptions in intensive syllogisms,
— that it must be affirmative.'
The necessity of the last rule is equally manifest as that of the
preceding. It is : — The conclusion must corre-
spond in quantity with the subsumption, and in
quality with the sumption. "This rule is otherwise enounced by
logicians : — The conclusion must always follow the weaker or worser
part, — the negative and the particular being held to be weaker or
worser in relation to the affirmative and universal. The conclusion,
in extensive categoricals (with which we are at present occupied)
is made up of the minor term, as subject, and of the major tenn, as
predicate. Now, as the relation of these two terms to each other
is determined by their relation to the middle term, and as the mid-
dle term is compared with the major term in the sumption ; it fol-
lows that the major term must hold the same relation to the minor
1 [Se« Bachmann, Logik, j 124, pp. 192, 194. Krng, Logik, { 82, p. 249. Cf. J 83, p. 264, and
Anm. 3. Drobisch, Logik, i 73, h. 65, §§ 42, } 109, p. 362. Facciolati, Rudimtnta hogiea,
44, pp. 34, 36. Sohulze, Logik, J 79, p. 114. P. iii. c. iii. p. 91.]
220 1.0 GIC. Lect. XVL
in the conclusion which it held to the middle in the sumption. If
then the sumption is affirmative, so likewise must be the conclusion;
on the other hand, if the sumption be negative, so likewise must be
ilie conclusion. In the subsumption, the minor term is compared
with the middle ; that is, the minor is affirmed as under the middle.
In the conclusion, the major term cannot, therefore, be predicated
of more things than were affirmed as under the middle tenn in the
subsumption. Is the subsumption, therefore, universal, so likewise
must be the conclusion ; on the contrary, is the former particular, so
likewise must be the latter."^
I Krag, LogOe, i 80, p. SCO-l. — Sd.
LECTURE XVII.
STOIOHEIOI. OQY.
SECTION II. — OF THE PRODUCTS OF THOUGHT.
III. — THE DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO INTERNAL
FORM.
A. SIMPLE. — CATEGORICAL. — IL DEDUCTIVE IN COMPREHEN-
SION — IlL INDUCTIVE IN EXTENSION AND COMPREHENSION.
— B. CONDITIONAL. — DISJUNCTIVE.
In my last Lecture, after terminating the consideration of the
constituent elements of the Categorical Syllo-
Recapitulation. . . i t i • ^i .'j^ e-
gism in general, whether in the quantity or
Comprehension or of Extension, I stated the subdivision of Cate-
gorical Syllogism into Deductive and Inductive — a division de-
termined by the difference of reasoning from the whole to the parts,
or from the parts to the whole. Of these, taking the former — the
Deductive — first into consideration, I was occupied, during the
remainder of the Lecture, in giving a view of the laws which, in
their higher or lower universality — in their remoter or more proxi-
mate application, govern the legitimacy and regularity of Deductive
Categorical Syllogisms. Of these laws, the highest are the axioms
of Identity and Contradiction, by which all Categorical Syllogisms
ai'e controlled. These, when proximately applied to the two forms
of Deductive Categoricals, determined by the two quantities of
Comprehension and Extension, constitute two canons, — the canon
of the Intensive Syllogism being: What belongs to the predicate
belongs also to the subject — what is repugnant to the predicate is
repugnant also to the subject; — the c'anon of the Extensive Syllo-
gism being: What belongs to the genus belongs also to the species
and individual — what is repugnant to the genus is repugnant also
222 LOGIC. Lect. XVII.
to the species and individual. Each of these, however, in its more
proximate application, is still further developed into a plurality of
more explicit rules. In reference to Extensive Syllogism, the gen-
eral law, or the Dictum de Omni et de NuUo (as it is technically
called) is evolved into a series of rules, which have been multiplied
to twelve, are usually recalled to six, but which, throwing out of
account irregular and imperfect syllogism, may be conveniently
reduced to three. These are, I. An Extensive Categorical Deduc-
tive Syllogism must have three, and only three, terms — constitut-
ing three, and only three, propositions. II. The sumption must in
quantity be definite (t. e^ universal or singular) ; the subsumption
must in quality be affirmative. III. The concIusioH must eorre*
spond in quantity with the subsumption, and in quality with the
sumption. The Lecture concluded with an explanation of these
rules in detail.
We have now, therefore, next to consider into what rales the
law of Intensive or Comprehensive Syllogism
2.TbeintenBiTeC«te- is developed, in its more proximate application.
fforioal Deductive Sy I- ^-p ^. • ' • -i . • n •
J . J«Jow, as the mtensive and extensive syllogisms
are always the counterparts of each other, the
proximate rules of the two forms must, consequently, be either pre-
cisely the same, or precisely the converse of each other. Accord-
ingly, taking the three rules of extensive syllogisms, we find that
the first law is also, without difference, a rule of intensive syllo-
gisms; But the second and third, to maintain' their essential iden-
tity, must be externally converted ; for to change an extensive
syllogism into an intensive, we must transpose the order or subor-
dination of the two premises, and reverse the reciprocal relation of
the terms. The three general rules of an Intensive Categorical
Deductive Syllogism will, therefore, stand as follows:
% LXI. An Intensive Categorical Deductive Syllogism, that
is, one of Depth, if regularly and fully ex-
the*'nten»ivecat!go^ prcsscd, is govcmed by the three following
loal Dedaotiva Syllo- rulcS \
I. It must have three, and only three,
terms, — constituting three, and only three, propositions.
II. Of the premises, the Sumption must in quality be Affir-
mative, and the Subsumption in quantity Definite (that is, uni-
versal or singular).
III. The Conclusion must not exceed the Sumption in Quan>
tity, and in Quality must agree with the Subsamptioiu
Lect. XVn. LOGIC. 228
In regard to the first of these rules, — the rule which is identical
for syllogisms whether extensive or intensive, it
p ication. jg needless to say anything ; for all that I stated
First Rule. J J Ss '
in regard to it under the first of these forms, is
valid in regard to it under the second.
I proceed to the second, which is, — The sumption must in qual-
ity be affirmative, the subsumption must in quan-
tity be definite (that is, universal or singular).
And, here, we have to answer the question, — Why in an intensive
syllogism must the sumption be affirmative in quality, the subsump-
tion definite in quantity ? Let us take the following syllogism as
explicated :
S comprehends M ;
H does not comprehend P ;
Therefore, S does not comprehend P.
Prudence comprehends virtue;
But virtue does not comprehend blameworthy;
Therefore, prudence does not comprehend hlanuvxrrOiy.
Here all goes on regularly. We descend from the major term pru^
dence to the middle term virtue., and from the middle term virtue td
the minor term blameworthy. But let us reverse the premises.
We at once see that though there is still a discoverable meaning,
it is not directly given, and that we must rectify and restoi-e in
thought what is perverse and preposterous in expression. In the
previous example, the sumption is affirmative, the subsumption neg.
ative. Now let us take a negative sumption :
S does not comprehend M ;
But M comprehends P.
Here there is no conclusion competent, for we can neither say S
comprehends P, nor S does not comprehend P. Or to take a con-
crete example :
Prudence does not comprehend learning;
But learning comprehends prca'seioorthy.
We can draw, it is evident, no concrusion ; for we can neither say,
from the relation of the two propositions, that Prudence compre-
hends prcuiseworthyyX\ov that Prudence does not comprehend prawe^
worthy.
224 LOGIC. " Lect. XVIL
The reason why an extensive syllogism requires a nniversal sump-
tion, and an intensive syllogism an affirmative.
Grounds of the rules and why the One requires an affirmative and
regarding Sumption ^j^g ^^j^g^ ^ definite subsumption, is the follow-
and Subsumption in . _,, ,. . i i n •
Extensive and Com- i°g * ^he Condition common to both syllogisms
prehensive Syllogisms. is that the sumption should express a rule. But
in the extensive syllogism this law is an univer-
sal rule, that is, a rule to which there is no exception ; but then it
may be expressed either in an affirmative or in a negative form,
whereas in the intensive syllogism this law is expressed as a posi-
tion, as a fact, and, therefore, admits only of an affirmative form,
but, as it is not necessarily univei*sal, it admits of limitations or
exceptions. This opposite character of the sumptions of the two
forms of syllogisms is correspondent to the opposite character of
their subsumptions. In the extensive syllogism, the subsumption
is, and can only be, an affirmative declaration of the application of
the sumption as a universal rule. In the intensive syllogism, the
subsumption is either an affirmation or a negation of the applica-
tion of the sumption as a positive law. Hence it is that in an in-
tensive syllogism the major premise is necessarily an affirmative,
while the minor may be either an affirmative or a negative propo-
sition.
In regard to the second clause of the second rule, the reason
why the subsumption in an intensive syllogism must be definite in
quantity, is because it would otherwise be impossible to affirm or
deny of each other the minor and the major terms in the conclu-
sion. For example :
Sumption Prudence is a virtue ; i. e., Prudence comprthenda virtue.
Subsumption. . . Some virtue is praiaevoorthy ; i.e., Some virtue comprehends praiseworthy.
From these we can draw no conclusion, for the indefinite some vir-
tue docs not connect the major term prudence and the minor term
praiseworthy into the necessary relation of wliole and part.
In regard to the third rule, — The conclusion must be corre-
spondent in quantity with the sumption, and in
Third Rule. ,. . , , , . . .
quality with the subsumption, — it is not neces-
sary to say anything. Here, as in the extensive syllogism, the con-
clusion cannot be stronger than the weakest of its antecedents, that
is, if any premise be negative, the conclusion cannot but be negative
.ilso ; and if any premise be particular, the conclusion cannot be but
particular likewise ; and as a weaker quality is only found in the
subsumption, and a weaker quantity in ihe sunjption, it follows that
Lect. XVII. LOGIC. 225
(as the rule declares) the conclusion is regulated by the sumption
in regard to its quantity, and by the subsumption in regard to its
quality. It is, however, evident, that though warranted to draw a
universal conclusion from a general sumption, it is always compe-
tent to draw only a particular.
So much for the proximate laws by which Categorical Deductive
Syllogisms are governed, when considered as
II. Inductive cate- perfect and regular in external form. We shall,
gorieal Syllogisms. f ^ ^ ^ -j .i • i i
m the sequel, have to consider the special rules,
by which the varieties of Deductive Categorical Syllogisms, as de-
termined by their external form, are governed ; but at present we
must proceed to the general consideration of the other class of cat-
egorical syllogisms afforded by their internal form, — I mean those
of Induction, the discussion of which I shall commence by the
following paragraph :
i[ LXII. An Inductive Categorical Syllogism is a reasoning
in which we argue from the notion of all
Par. Lxn. Indue- |^jjg Constituent parts discretively, to the
tlve Categorical Syl- . /. , •
io»i«in,-what. notiou of , the constituted whole collect-
ively. Its general laws are identical Avith
those of the Deductive Categorical Syllogism, and it may be ■
expressed, in like manner, either in the form of an Intensive or
of an Extensive Syllogism.
We shall, in the sequel, have to consider more particularly the
nature and peculiarities of Logical Induction,
The views of logi- .^y^gn we come to treat of the Figure of Syllo-
cans regar ing e origm, and when we consider the nature of Logi-
naturc of Logical In- o ' ^ o
duction erroneous. cal or Formal, in contrast to Philosophical or
Real Induction, under the head of Modified
Logic. At present, I shall only say, that all you will find in logical
works of the character of logical induction is utterly erroneous;;
for almost all logicians, except Aristotle, consider induction, not as
regulated by the necessary laws of thought, but as determined by
the probabilities and presumptions of the sciences from which its ■
matter has accidentally been borrowed. They have not considered
it, logically, in its formal, but only, extralogically, in its material
conditions. Thus, logicians have treated in Logic of the inductive
inference from the parts to the whole, not as exclusively warranted
by the law of Identity, in the convertibility of the whole and all
its parts, but they have attempted to establish an illation from a few
of these parts to the whole; and this, either as supported by the
29
226 LOGIC. Lkct. XVll
general analogies of nature, or by the special presumptions afforded
by the several sciences of objective existence.'
Logicians, with the exception of Aristotle, who is, however, very
brief and unexplicit in his treatment of this sub-
The characters of ject, have thus deformed their science, and per-
d"^ rT*^! "mL* plexed the very simple doctrine of logical in-
riai, Induction. duction, by confounding formal with material
induction. All inductive reasoning is a reason-
ing from the parts to the whole; but the reasoning from the parts
to the whole in the various material or objective sciences, is very
different from the reasoning from the parts to the whole in the one
formal or subjective science of Logic. In the former, the illation is
not simply founded on the law of Identity, in the convertibility of
a whole and all its parts, but on certain presumptions drawn from
an experience or observation of the constancy of nature; so that, in
these sciences, the inference to the whole is rarely from all, but
generally from a small number of^ its constituent parts; conse-
quently, in them, the conclusion is rarely in truth an induction
properly so called, but a mixed conclusion, drawn on an inductive
presumption combined with a deductive premise. For example,
the physical philosopher thus reasons :
This, that, and the other magnet attrad iron ;
But this, that, and the other magnet represent all magnets;
Thertfore, aU magnets attract iron.
Now, in this syllogism, the legitimacy of the minor premise, 7%t»,
that, and the other magnet represent all magnets, is founded on the
principle, that nature is uniform and constant, and, on this gen-
eral principle, the reasoner is physically warranted in making a few
parts equivalent to the whole. But this process is wholly incom-
petent to the logician. The logician knows nothing of any princi-
ples except the laws of thought. He cannot transcend the sphere
of necessary, and pass into the sphere of probable, thinking; nor
can he bring back, and incorporate into his own formal science, the
conditions which regulate the procedure of the material sciences.
This being the case, induction is either not a logical process differ-
ent from deduction, for the induction of the objective philosopher,
in so far as it is formal, is in fact deductive ; or there must be an
induction governed by other laws than those which warrant the
induction of the objective philosopher. Now, if logicians had
I Compare Dittutimu, p. 168. —KD.
L.KCT. XATl. LOGIC. 227
looked to their own sciences, and not to sciences with which, as
logicians, they had no concern, they would have
Canons of the De- seen that there is a process of reasoning from
ductive and Inductive ^^^ ^^ ^^ ^^^ ^j^^j ^^ ^^^j ^^ ly^^ ^^^
Syllogisms — equally i i , . i •
foTmai. whole to the parts, that this process it governed
by its own laws, and is equally necessary and
independent as the other. The rule by which the Deductive Syllo-
gism is governed is : What belongs, or does not belong, to the con-
taining whole, belongs, or does not belong, to each and all of the
contained parts. The rule by which the Inductive Syllogism is
governed is : What belongs, or does not belong, to all the constitu-
ent parts, belongs, or does not belong, to the constituted whole.
These rules exclusively determine all fonnal inference ; whatever
transcends or violates them, transcends or violates Logic. Both
are equally absolute. It would be not less illegal to infer by the
deductive syllogism, an attribute belonging to the whole of some-
thing it was not conceived to contain as a part ; than by the induc-
tive, to conclude of the whole what is not conceived as a predicate
of all its constituent parts. In either case, the consequent is not
thought as determined by the antecedent; the premises do not
involve the conclusion.^
To take the example previously adduced as an illustration of a
Tbese reaMniDtrs material or philosophical induction, it would be
illustrated. thus expressed as a formal or logical :
This, that, and the other magnet attract iron;
But this, that, and the other magnet are all tnagnets ;
Therefore, all magnets attract iron.
Here 'the inference is determined exclusively by a law of thought.
In the subsumption, it is said. This, that, and the other magnet etc.,
are all magnets. This means. This, that, and the other magnet are,
that is, constitute, or rather, are conceived to constitute all magnets,
that is, the whole, — the class, — the genus m.agnet. If, therefore,
explicitly enounced, it will be as follows : This, that, and the other
magnet are conceived to constitute the whole class magnet. The
conclusion is — There/ore, all magnets attract iron. This, if expli-
cated, will give — Therefore, the whole class m,agnet is conceived to
attract iron. The whole syllogism, therefore, as a logical induc-
tion, will be :
1 [Cf. Krng, Logik, 4§ 166, 167. Sanderson, {QucBsiione$ in, Ah. Piior.^ X« iL 4. Till. > 816.
Compendium Log. Artis, L. iii. c. x. p. 112. ed.l610. — Ed.]
Wolf. PkU. Rationalis, H 477, 478. Scotus.
228 LOGIC. lect. xvn.
This that, and the other magnet attract iron;
But this, that, and the other magnet, etc., are conceived to constitvte the germs vtagnet;
Therefore, the genus magnet attracts iron.
It is almost needless to advert to an objection which, I see, among
othere, has misled Whately. It may be said
Objection obviated. , ' . rm . t t , ,
that tlie mmor, 2ms, that, ana the other maff-
net are all magnets, is manifestly false. This is a very superficial
objection. It is very true that neither here, nor indeed in almost
any of our inductions, is the statement objectively correct, — that
the enumerated particulars are really equivalent to the whole or
class which they constitute, or in which they are contained. But,
as an objection to a logical syllogism, it is wholly incompetent, as
wholly extralogical. For the logician has a right to suppose any
material impossibility, any material falsity ; he takes no account of
what is objectively impossible or false, and has a right to assume
what premises he please, provided that they do not involve a con-
tradiction in terms. In the example in question, the subsumption,
This, that, and the other magnet are all magnets, has been already
explained to mean, not that they really are so, but merely that they
are so thought to be. It is only on the supposition of this, that, and
the other magnet, etc., being conceived to con-
FonnnUe for Indue- gtitutc the class magnet, that the inference pro-
l ogisms Ti ceeds, and, on this supposition, it will not be
Comprehension and _ ' _ .
Kxtension. denied that the inference is necessary. I stated
that an inductive syllogism is equally competent
in comprehension and in extension. For example, let us suppose
that X, y, z, represent parts, and the letters A and B wholes, and
we have the following formula of an inductive syllogism in
Comprehension : *
X, y, z, constitute A ;
A compreitends B ;
Therefore, x, y, z, comprehend B.
This, if converted into an extensive syllogism, by transposing
the premises and revei'sing the copula, gives :
A is contained under B ;
X, y, z, constitute A ;
Thertfore, x, y, z, are contained under B.
But in this syllogism it is evident that the premises are in an un-
natural order. We must not, therefore, here transpose the premises,
as we do in converting a deductive categorical of comprehension
lect. xvn.
LOGIC.
229
into one of extension. We may obtain an inductive syllogism in
two different forms, and in either comprehension or extension,
according as the parts stand for the major, or for the middle term.
If the minor term is formed of the parts, it is evident there is no
induction ; for, in this case, they only constitute that quantity of
the syllogism which is always a part, and never a whole. Let x, y,
z represent the parts; where not superseded by x, y, z, S will repre-
sent the major term in a comprehensive, and the minor term in an
extensive syllogism; P will represent the major term in an exten-
sive, and the minor term in a comprehensive syllogism, and M the
middle term in both. I shall first take the Inductive Syllogism
of Comprehension.
FiKST Case, — (The parts holding the
place of the m^or term S.)
X, y, z constitute M ;
M comprehends P;
Therefore, x, y, z comprehend P.
Second Case, — (The parts holdiug the
place of the middle term.)
S comprehends x, y, z;
X, y, z constitute P ;
Therefore, S comprehends P.
Again, in the Inductive Syllogism of Extension :
First Case, — (The parts holding the
place of the major term P.)
X, y, z constitute M ;
S is contained under M ;
Therefore S is contained under x, y, z.
Second Case, — (The parts holding the
place of the middle term.)
X, y, z are contained under P;
X, y, z constitute S;
Theiffore, S in contained under P.
Before leaving this subject, I may notice that the logical indue
tion maintained by Whately and many others,
diverges even more than that of the older logi-
cians from the truth, inasmuch as it makes this
syllogism a deductive syllogism, of which the
sumption, which is usually understood and not
expressed, is always substantially the same, namely, "What belongs
(or does not belong) to the individuals we have
examined, belongs (or does not belong) to the
whole class under Avhich they are contained."
This doctrine was/first, I think, introduced by Wolf,* for the
Whately and others
erroneously make the
Inductive Syllogism
Deductive.
Doctrine of the
older logicians.
1 ICf. Wolf. Philosophta Rationalis, § 479, (Entbymemate) vel major vel minor prsemis-
flrst ed. 1728. So, before Wolf, Schramm, sarum, in hoc (Inductione) semper major
AriMoi. Philos. Principia, p. 27, ed. Helmst., propositio subintelligitur." Refers as lo,-
1718. " Induct! jue ex multis siugularibus lows — '■'■ De Inductione^ Philos. AUorf., Di.sp.
c«>nigitur universale supposito loco majoris xxvi. p. 252 et seg." See also Crakanthorpe^
I'Fopositionis hoc canone : Qufcquid competit iog-ica, c. xx. p. 217, ed. 1677. [CL Discussions,
cmuibus partibus, hoc competit toti; in isto p. 170, note. — Ed.]
2SQ LOGIC. Lkct. xvu
previous logicians viewed the subsumption as the common, and,
therefore, the suppressed premise, this premise always stating that
the individuals, or particulars enumei-ated, made up the class under
which they were severally contained.^ For example, in the instance
from the magnet we have already taken, the subsumption would be,
This^ tfiat, and the other magnet^ and so forth^ are the whole class
magnet. This doctrine of the older logicians is
Correct as far as it .. c -^ j ^ i -^ i
correct as lar as it goes ; and, to make it abso-
lutely correct, it would only have been necessary
to have established the distinction between the logical induction as
governed by the a priori conditions of thought, and philosophical
induction as legitimated by the a posteriori conditions of the mat-
ter, about which the inquiry is conversant. This, however, was not
done, and the whole doctrine of logical induction was corrupted
and confounded by logicians introducing into their science the con-
sideration of various kinds of matter, and admitting as logical an
induction supposed imperfect, that is, one in which there was infer-
ence to the whole from some only of the constituent parts. This
Imperfect Induction, they held in contingent
oc nne o mper- matter to be contingent, in necessary matter to
feet Induction. ...
be necessary, as if a logical inference were not,
in all cases, necessary, and only necessary as governed by the neces-
sary laws of thought. This misapprehension of the nature of logi-
cal or foiTnal induction, and its difference from philosophical or
material, has been the reason why Bacon is at
Bacon at fault in his fault Jq jjjg criticism of Aristotlc's doctriuc of
criticism of Aristotle's -j^. -»:, ii- i .^•13..
. .. ,, J .. induction. Jbor, looking only at the doctrine
doctrine of Induction. ^ ' ?
of the inductive syllogism given by Aristotle
in the Organon^ and not perceiving that the question there was
only concerning the nature of induction as governed by the laws of
thought, he forthwith assumed that this was the induction practised
by the Stagirite in his study of nature, and, in the teeth both of
the precept and practice of the philosopher, condemned the Aris-
totelic induction in the mass, as flying at once to general principles
from the hasty enumeration of a few individual instances. Induc-
tion, as I mentioned, will, however, once and again, engage our
attention in the sequel ; but I have thought it proper to be some-
what explicit, that you might carry with you a clearer conception
i [On Indoetion in general, sec Zabarella, xx. p. 254 Keckermann, Opera, t. i. pp. 259,
Tabula in An. Prior, p. 170 << sei].. Optra Log- 763. Lambert, Neuet Organon, i H 286, 287,
tea, (Appendix) Molin«ns, EUtrtenta Logica, p. 183. Kugenias AoyiK)), p. 410. Jo. Fr.
L. i. c. ii. p. 99. Isendoorn, Cursus Logieus, Pious Mirandulanus.] [Opera, Examen DoU
L. iii. q. ii. p. 361. Crellius, Isagoge, L. iii. c. Vonif. Gent. L. r. p 746 et uq. — 1Sd>.]
Lkct. XVIL LOGIC. 231
of the nature of this process, as contrasted with the process of the
Deductive Syllogism.
Having terminated the general consideration of Categorical Syl-
logisms, Deductive and Inductive, I now pro-
B. Conditional Syi- ^^^^ ^^ ^^^ ^^^^ ^j^^^ ^^ Reasonings afforded
1. Difliunctive. ^7 ^^^ internal form ; I mean the class of Dis-
junctive Syllogisms.
% LXIII. A Disjunctive Syllogism is a reasoning, whose
Par Lxin A Dia- forai is determined by the law of Excluded
jtmctive ayiioKism,- Middle, and whose sumption is accordingly
''^'" a disjunctive proposition, either of Contra-
diction (as, A is either B or not B) — or of Contrariety (as, A
is either B, or C, or D). In such a judgment, it is enounced
that B or not B, or that B, C, or D, as opposite notions taken
together and constituting a totality, are each of them a possi-
ble, and one or other of them a necessary, predicate of A. To
determine which of these belongs, or does not belong to A, the
subsumption must either affirm one of the predicates, and the
conclusion, eo ipso, consequently, deny the other or others ; or
it must deny one or more of them, and thus necessitate in the
conclusion, either the determinate affirmation of the other, or
the indeterminate affirmation of the others. A Disjunctive
Syllogism is thus either Affirmative, constituting the Modus
ponens, or Modus ponendo tollens, or Negative, constituting
the Modus tollens, or Modus tollendo ponens.
In each of these modes there are two cases, which I compre-
hend in the following mnemonic verses :
(A) Affirmative, ok Modus ponendo tollkns : —
1. Faileris autfaUor ; faJlor ; non fdUeris ergo.
2. FaUeris out faUor ; tu faileris; ergo ego nedum.
(B) Negative, ok Modus tollendo ponens: —
1. Faileris autfaUor ; non faUor; faUeris ergo. ^
2. FaUeris aut fallor ; non faUeris ; ergo ego faUor.
In illustration of this paragraph, I have defined a 'disjunctive
syllogism, one whose form is determined by the
Explication. J a ■> J
law of Excluded Middle, and whose sumption
n, accordingly, a disjunctive proposition. I have not, as logicians
in general do, defined it directly, — a syllogism whose major pre-
I This line is from Furehot, Instit. Phiios. Logiea, 1. 1, p. I&i. The others are the Anthor'k
own. — Ed.
232 LOGIC. Lect. XVIL
mise is a disjunctive proposition. For though it be tnie that every
disjunctive syllogism has a disjunctive major
sy ogism \n premise, the converse is not true ; for every syl-
disjuuctive major pre- * , ... .
mise is not necessarily logism that has a disjunctive sumption is not,
a disjunctive reason- on that account, neccssanly a disjunctive syllo-
'"*■ gism. For a disjunctive syllogism only emerges,
when the conclusion has reference to the relation of reciprocal
affirmation and negation subsisting between the disjunct members
in the m:!Jor premise, — a condition not, however, contained in the
mere existence of the disjunctive sumption.^ For example, in the
syliogisra :
B is either C or D ;
But A IS B ;
Therefore, A is either C or D.
This syllogism is as much a reasoning determined, not by the law
of Excluded Middle, but solely by the law of Identity, as the fol-
lowing :
BisC.
AtsB.
There/ore, A is C.
For in both we conclude, — C (in one, C or D) is an attribute of B ;
but B is an attribute of A : therefore^ C (C or D) is an attribute of
A, — a process, in either case, regulated exclusively by the law of
Identity.^
This being premised, I now proceed to a closer examination of
the nature of this reasoning, and shall, fii*st, give you a general
notion of its procedure ; then, secondly, discuss its principle ; and,
thirdly, its constituent parts.
,o „ , . , 1°. The general form of the Disjunctive Syl-
1°. General view of => .
the Di^unctive Syiio- logism may be given in the following scheme,
«i»™- in which you will observe there is a common
sumption to the negative and affirmative modes :
, . _ , - A 15 either B or C.
(a.) Formnla for a
Syllogism with two Affirmative, or Modus Negative, or Modus tol-
disjunct members. ponekdo tollens —
Now A IS B ;
Therefore, A is not C,
LENDO PONEK8 —
Now A IS tmt B;
Therefore, A is C.
1 Cf Scheibler, Opera Lngiea, Tars. iv. p. 553. S Sigwart, pp. 164, 157. I Uandbuch zur For-
'* Neque enim syllogismus disjunctus semper hsungfti Ubr' die Logik,voH H. C. W. Sigteartf
eirt, cum propositio est disjuuctiva, sed cum Sd ed. Tubingen, idSft, H 246, 248. — £d.]
totaquxstiodisponitur in propojiiionc." £d.
Lkct. XVIL logic. 233
Or, in a concrete example ;
Sempronius is either honest or dishonest.
Affibmative, or Modus poxendo Negative, or Modus tollendo
tollen8 — posen8 —
Nau) Sempronius is honest ;
Now Sempronius is not honest ;
Therefore, Sempronius is not dishonest. Therefore, Sempronius is dishonest.
" This formula is, however, only calculated for the case in which
there are only two disjunct members, that is, for
(b.) Formula for a i]^q c^ge of negative or contradictory opposition :
y ogism wi ™ore ^^^^ -j. ^j^^ disjunct members are more than two,
than two disjunct ...
members. that is, if there is a positive or contrary opposi-
tion, there is then a twofold or manifold employ-
ment of the Modus ponendo toUens and Modus toUendo ponens^
according as the affirmation and negation is determinate or indeter-
minate. I^ in the Modus ponendo tollens, one disjunct member is
detenninately affirmed, then all the others are denied ; and if sev-
eral disjunct members are indeterminately affirmed except one, then
only that one is denied. If, in the Modu^ tollendo ponens, a single
member of the disjunction b6 denied, then some one of the others is
determinately affirmed ; and if several be denied, so that one alone
is left, then this one is determinately affirmed." * This will appear
more clearly from the following formulae. Let the common Sumption
both of the Modus poneiido tollens and Modus toUendo ponens be -
A is either B, or C or D.
I. The Modus Poxendo Tou^ns —
First Case. A is either B or C or D ;
Now A is B ;
Therefore, A is neither C nor D.
Second Case. A is either B or C or D;
Now A is either B or C ;
Therefore, A is notD.
n. The Modus Tollendo Ponens —
First Case. Aiseitter B or C or D;
Now A is not B ;
Therefore, A is either C or D.
Second Case. A iset</icr B or Cor D;
Now A is neither B nor C;
Ther^ore, A is D.
I Eager, L<«tfe, { 93, p. 180.— Ed.
30
234 LOGIC. Lect. xvn.
Or, to take these in concrete examples, let the Common Sump-
tion be :
The ancients were in genius either superior to the moderns, or inferior, or equal.
I. The Modus Ponendo Tollens —
First Case. The ancients were in genius either superior to the modems, or inferia,
or equal ;
Now the ancients were superior ;
Therefore, the ancients were neUher inferior nor equal.
Second Case. The ancients were in genius either superior to the modems, or inferior,
or equal;
Now the ancients uxre either superior or equal ;
Therefore, the ancients uxre not inferior.
n. The Modus Tollendo Ponens —
First Case. The ancients uxre in genius either superior to the modems, or inferior,
or equal.
Now the ancients were not inferior ;
Therefore, the ancients uxre either superior or equal.
Second Case. The ancients uxre in genius either superior to the modems, or inferior,
or equal. •
Now the ancients uxre neither inferior nor equal ;
Therefore, the ancients uxre superuA-.
Such is a general view of its procedure. Now, 2*, for its prin^
ciple.
2°. The principle of « jf ^^e essential character of the Disjunctive
un V y Syllogism consist in this, — that the affirmation
or negation, or, what is a better expression, the
position or sublation, of one or other of two contradictory attributes
follows from the subsumption of the opposite ; — there is necessarily
implied in the disjunctive process, that, when of two opposite predi-
cates one is posited or affirmed, the other is sublated or denied ;
and that, when the one is sublated or denied, the other is posited or
affirmed. But the proposition, — that of two repugnant attributes,
the one being posited, the other must be sublated, and the one
being sublated, the other must be posited, — is at once manifestly
the law by which the disjunctive syllogism is governed, and mani-
festly only an application of the law of Excluded Middle. For the
Modus ponendo tollens there is the special rule, — If the one charac-
ter be posited tlie other character is sublated ; and for the Modus
tollendo ponens there is the special rule, — If the one character be
sublated, the other character is posited. The law of the disjunctive
syllogism is here enounced, only in reference to the case in which
Lect. XVn. LOGIC. 236
the members of disjunction are contradictorily opposed. An oppo-
sition of contrariety is not of purely logical concernment ; and a
disjunctive syllogism with characters opposed in contrariety, in fact,
consists of as many pure disjunctive syllogisms as there are opposing
predicates." ^
3°. I now go to the third and last matter of consideration, — the
several parts of a Disjunctive Syllogism.
8°. The several parts "The question concerning the special laws of
of aDisiunctire St11o> j* • x- h • i ^ • ^i
a disjunctive syllogism, or, what is the same
thing, what is the original and necessary "form
of a disjunctive syllogism, as determined by its general principle or
law, — this question may be asked, not only in reference to the
whole syllogism, but likewise in reference to its several parts. The
original and necessary form of a disjunctive syllogism consists, as
we have seen, in the reciprocal position or sublation of contradictory
characters, by the subsumption of one or other. Hence it follows,
that the disjunctive syllogism must, like the categorical, involve a
threefold judgment, viz. : 1°, A judgment in which a subject is
determined by two contradictory predicates ; 2°, A judgment in
which one or other of the opposite predicates is subsumed, that is,
is affirmed, either as existent or non-existent; and, 3°, A judgment
in which the final decision is enounced concerning the existence or
non-existence of one of the repugnant or reciprocally exclusive pre-
dicates. But in these three propositions, as in the three proposi'
tions of a categorical syllogism, there can only be three principal
notions — viz., the notion of a subject, and the notion of two con-
tradictory attributes, which are generally enounced in the sumption,
and of which one is posited or sublated in the subsumption, in order
that in the conclusion the other may be sublatedor posited. The
case of contrary opposition is, as we have seen, easily reconciled and
reduced to that of contradictory opposition." ^ The laws of the
several parts of a disjunctive syllogism, or more properly the origi-
nal and necessary form of these several parts, are given in the
following paragraph:
^ LXIV. 1". A regular and perfect Disjunctive Syllogism
must have three propositions, in which, if
Par. iixiv. The laws tj^e sumptiou be simple and the disjunction
of the Dl8janotive i i • i 11 . . ,
syuogism. purely logical, only three principal notions
can be found.
2*, The Sumption, in relation to its quantity and quality, is
lEsser, Log^, {94. — Ed. i 'Eaaer, Logik, i %.~~Ed.
236 LOGIC. Lect. xvii.
always uniform, being Univei-sal and AfBrmative ; but tlie Sub-
sumption is susceptible of various forms in both relations.
3°, The Conclusion corresponds in quantity with the sub-
sumption, and is opposed to it in quality.*
The first rule is, — A regular and perfect disjunctive syllogism
must have three propositions, in which, if the
xp ica ion. sumption be simple, and the disjunction purely
logical, only three principal notions can be
found. "Like the categorical syllogism, the disjunctive consists of
a sumption, constituting the general rule ; of a subsumption, con-
taining its application ; and of a conclusion, expressing the judg-
ment inferred. Disjunctive syllogisms are, therefore, true and
genuine reasonings; and if in the sumption the disjunction be
contradictory, there are in the syllogism only three principal no-
tions. In the case of contrary disjunctions, there may, indeed,
appear a greater number of notions ; but as such syllogisms are in
reality composite, and are made up of a plurality of syllogisms with
a contradictory disjunction, this objection to the truth of the rule is
as little valid as the circumstance, that the subject in the sumption
is sometimes twofold, threefold, fourfold, or manifold ; as, for exam-
ple, in the sumption — John^ James^ Thomas^ are either virtuous or
vicious. For this is a copulative proposition, which is composed of
three simple propositions — viz. John is, etc. If, therefore, there be
such a sumption at the head of a disjunctive syllogism, it is in this
case, likewise, composite, and may be analyzed into as many simple
syllogisms with three principal notions, as there are simple proposi-
tions into which the sumption may be resolved." *
The. second rule is, — The sumption is, in relation to its quantity
and quality, always uniform, — being universal
Second Rule. , V. ' / , , . .
and affirmative ; but the subsumption is suscep-
tible of different forms in both relations. If we look, indeed, to the
subject alone, it may seem to be possibly equally general or particu-
lar ; for Ave can equally say of some as of all A, that they are either
B or C. But as all universality is relative, and as the sumption is
always more extensive or more comprehensive than the subsump-
tion, it is thus true that the sumption is always general. Again,
looking to the predicate, or, as it is complex, to the predicates alone,
they, as exclusive of each other, appear to involve a negation. But
in looking at the Whole proposition, that is, at the subject, the
copula, and the predicates in connection, we see at once that the
1 Etser, ). e. Krug, Logik, { 80- — £^0. * Krug, Logik, I. e. — £d.
LiiCT. XVII. LOGIC. 237
copula is affirmative, for the negation involved in the predicates is
confined to that term alone.^
In regard to the third rule, which enounces, — That the con-
clusion should have the same quantity with the
Third Rule. , . , . ,. . .
subsumption, but an opposite quahty, — it is
requisite to say nothing, as the first clause is only a special applica-
tion of the rule common to all syllogisms, that the conclusion can
contain nothing more than the premises, and must, therefore, follow
the weaker j^art ; and the second is self-evident, as only a special
application of the principle of Excluded Middle, for, on this law, if
one contradictory be affirmed in the subsumption, the other must be
denied in the conclusion, and if one contradictory be denied in
the subsumption, the other must be affirmed in the conclusion.
The Disjunctive, like every other species of syllogism, may be
either a reasoning in the quantity of Compre-
The Disjunctive syi- hgngjon ^j. ^ reasoning in the quantity of Ex-
logism of Comprehen- •mi i ^ i
sion aud Extension. tension. The Contrast, however, of these two
quantities is not manifested in the same signal
manner in the disjunctive as in the categorical deductive syllogism,
more especially of the first figure. In the categorical deductive
syllogism, the reasonings in the two counter quantities are obtrusively
distinguished by a complete conversion, not only of the internal
significance, but of the external appearance of the syllogism. For
not only do the relative terms change places in the relation of
whole and part, but the consecution of the antecedents is revereed;
the minor premise in the one syllogism becoming the major premise
in the other. This, however, is not the case in disjunctive syllo-
gisms. Here the same proposition is, in both quantities, always the
major premise ; and the whole change that takes place in convert-
ing a disjunctive syllogism of the one quantity into a disjunctive
syllogism of the other, is in the silent reversal of the copula from
one of its meanings to another. This, however, as it determines no
apparent difference in single propositions, and as the disjunctive
sumption remains always the same proposition, out of which the
subsumption and the conclusion are evolved, in the one quantity ns
in the other, — the reversal of the sumption, from extension to com-
prehension, or from comprehension to extension.
Examples. ... , ,
occasions neither a real nor an apparent change
in the syllogism. Take, for example, the disjunctive syllogism :
1 See Krug, Logik, $ 86, Anm. 2. Eb. — quantitatemnisisnarumpartium . . . sicut
[Bactimann, Logik, § 141, p. 854. Contra: I'-onosilio Hypothetica habet tantum quan-
Twesten, Logik, § 137, ed. 1825, p. 119. Esser. titatem suarum partium." See above, p. 174.
Lngik, § 95. Derodon, Logira R'stiiuta, p. and note 1. — Ed.]
676.] [Propositio Disjunctiva nullani habet
238 LOGIC. Lkct. XVIl.
Flato is either learned or unlearned ;
But Plato is learned.
Therefore, Plato is not unlearned.
Now let us explicate this into an intensive and into an extensive
syllogism. As in Intensive Syllogism it will stand :
Plato comprehends either the attribute learned or the attribute wnHeamed;
But Plato comprehends the attribute learned ;
Ther^ore, etc.
As an Extensive Syllogism it will stand ;
Plato is contained either under the dass learned or the doss uhleamed;
But Plato is contained under the class learned ;
Therefore, etc.
From this it appears, that, though the difference of reasoning in
the several quantities of comprehension and extension obtains in
disjunctive, as in all other syllogisms, it does not, in the disjunctive
syllogism, determine the same remarkable change in the external
construction and consecution of the parts, which it does in categoric
cal syllogisms.
LECTURE XVIII.
STOIOHEIOLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT
III. — DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO INTERNAL
FORM.
B. CONDITIONAL. — HYPOTHETICAL AND HYPOTHETICO-
DISJUNCTIVE.
Havtng now considered Categorical and Disjunctive Syllogisms,
the next class of Reasonings afforded by the difference of Internal
or Essential form is the Hypothetical ; and the general nature of
these syllogisms is expressed in the following paragraph :
^ LXV. An Hypothetical Syllogism is a reasoning whose
form is determined by the law of Reason
Par. LXV. a. Hypo- and Consequent. It is, therefore, reerulated
ita general character. by the two pi'inciples of which that law is
the complement, — the one, — With the
reason, the consequent is affirmed; the other, — With the
consequent, the reason is denied : and these two princij^les
severally afford the condition of its Affirmative or Constructive,
and of its N'egative or Destructive form (Modus ponens et
Modus tollens). The sumption or general rule in such a syllo-
gism is necessarily an hypothetical proposition (^ A is, then B
is). In such a proposition it is merely enounced that the prior
member (A) and the posterior member (B) stand to each other
in the relation of reason and consequent, if existing, but with-
out it being determined whether they really exist or not.
Such determination must follow in the subsumption and con-
clusion ; and that, either by the absolute affirmation of the
240
LOGIC.
lect. xvm.
antecedent in the subsuraption, and the illative affirmation of
the consequent in the conclusion (the modus poneiu) ; or by
the absolute negation of the consequent in the subsuraption,
and the illative negation of the antecedent in the conclusion
(the modus toUens)} The general form of an hypothetical
syllogism^ is, therefore, the following ;
CokniDoa SOinption — If A is, thai B is;
1, 2,
Moons PoxEKs: Modus Tolleks:
But A IS ; BtU B is not ;
Therefore, B is. Therefore, A is not.
Or,
A B
1) Modus Ponens — Si poteris possum ; sed tu potes; ergo ego possum.
B A
2) Modus Tollens — Si poteris possum ; nan possum; nee potes ergo.^
1°. Hypothetical syl-
lugism ill geueral.
Contains three propo-
■itions.
In illustrating this paragraph, I shall consider, 1°, This species of
syllogism in general ; 2°, Its peculiar principle ;
^ ' and, 3", Its special laws.
1°, "Like every other species of simple syllogism, the Hypothetical
is made up of three propositions, — a sumption,
a subsuraption, and a conclusion. There must,
in the first place, be an hypothetical proposition
holding the place of a general rule, and from
this proposition the other parts of the syllogism
must be deduced. This first proposition, therefore, contains a
sumption. But as this proposition contains a relative and correla-
tive member, — one member, the relative clause, enouncing a thing
as conditioning ; the other, the correlative clause, enouncing a thing
as conditioned ; and as the whole proposition enounces merely the
dependency between these relatives, and judges nothing in regard
to their existence considered apart and in themselves, — ^ this
enonncement must be made in a second proposition, which shall
take out of the sumption one or other of its relatives, and categoii-
' [For urc of terms ponfns and toUens, see
I'-octhius, De SylloKismo HypothetUo, Opera, p.
i:il. Wolf. Phil. Rat., i 403, 410. Mark Dun-
can uses the terms " a positlone ad posi-
tionem," and " a rt-motione ad remotioncm."
[Iiiftitutionex Logiccr, L iv. c. 6, 4 4, p. 240.
Cf. p. 243, Salmurii, 1812. — Ed.]
2 (On the Hypothetical Syllogism in gen-
eral, gee Ammonius, In Dt Int-rp., rrooom.,
f. 3, Vcnetiis, 1648. rhilopoiius, In AnaL
Prior., I. c. 23, f. 60, Venet., 1536. Magen-
tinns. In Anal. Prior., f. 16, b. Alex. Aphro-
disiensis. In An.jl. Prior., ff. 87, 8S, 109, 130.
Aid. 1520. In Topica, f. 65, Aid.. 1513. Anony-
mous Author, On Syllogisms, f. 44, ed. 153 >.
Schciblcr, Opera Logica, pars iv. p. 643. Bol-
zano, W'issen.vha/liUfhre, Logtk, ii. p. 510
Waifz, Organon, In An. Prior., 1. c 23 ]
■'' 'I'heso lines are the Author's own. — I'd
I
Lect. XVm. LOGIC. 241
cally enounce its existence or its non-existence. This second pro-
position contains, therefore, a subsumption ; and, through this sub-
sumption, a judgment is likewise detemiiued, in a third proposition,
with regard to the other relative. This last proposition, therefore,
contains the conclusion proper of the syllogism."
" But as the sumption in an hypothetical syllogism contains two
relative clauses, — an antecedent and a conse-
in a hypothetical quent, — it, therefore, appears double ; and as
syllogism there is com- . , « . , i i . i
petent a twofold kind either of its two members may be taken m the
of reasoning,— the »wo- subsumption, there is, consequently, competent
rfiM poneTis and modtu ^ twofold kind of reasoning. For we can either,
° ""' in the first place, conclude from the truth of the
antecedent to the truth of the consequent ; or, in the second place,
conclude from the falsehood of the consequent to the falsehood of
the antecedent. The former of these modes of hypothetical infer
ence constitutes what is sometimes called the Constructive Hypo-
thetical, but more properly the 3fodus JPonens : — the latter what
is sometimes called the Destructive hypothetical, but more properfy
the Modu9 ToUensT^ As examples of the two modes:
HodOR Ponens — If Socrates he virtuous, he merits esteem ;
But Socrates is virtuous ;
Therefore, he merits esteem. ^
Modus Tollens — If Socrates be virtuous, he merits esteem ;
But Socrates does not merit esteem ;
Therefore, he is not virtuous.^
So much for the character of the Hypothetical Syllogisnt id 5
general. I now proceed to consider its peculiar principle.
2", " If the essential nature of an Hypothetical Syllogism consist
in this, — that the subsumption affirms or denies one or other of the
two parts of a thought, standing to each other in the relation
of the thing conditioning and the thing conditioned, it will be the
1 Krug, Logik, § 81, Anm. 1, p. 254. Com- Here, 1/ it be day is called ri fryovnores-^ .
pare Esser, Logik, § 90, p. 173. — Ed. both by Peripatetics and by Stoics; the sun it
2 [NomenelatBre of Tlieophrastus, End©- on the earth, is called rh iir^nevov by Teripa-
mus, and other PeripateUcs, in regard to tetics, ih \rjyoy by Stoics. The whole. If it
Hypothetical Syllogism, in contrast with that be day, the sun is on the earth, is called ri, -
of the Stoics. vwrififjifvov by Peripatetics, rb TpoiriK6v by
Upiytmra yo^invra <(>oryal ( I'eripateUc), gtoics : But it is day, is HfraX-q^is to Peri-
are called by the Stoics respectively, rvy- patetics, icp6a\7j^is to Stoics. Therefore, the
Xivoin-a iK<popiKi, Xficrd. ,„„ ,-, „„ the earth, is av/iirepafffia to Peripa-
Take this Hypothetical Syllogism : tetics, iiri<f>opd to Stoics. See Philoponus, ,
Vit he day, the «a, is on tJu: earth: ^" ^"'^- -^''^■' ^- '• "• ^' ^ 60 «. e^. VenCt
Buiitisdav; ^536. Brandis, Scholia, p. 169. Cf. Anony-
Thrr^ore, the tun U on the etertk. " ■ ' < mous Anthor, On Syllogisms, f. 44.]
31
242 LOGIC. Lect. XVIIi.
law of an hypothetical syllogism, that, — If the condition or antece-
dent be affirmed, so also must be the eondi-
2". Its peculiar prin- tioned OF consequent, and that if the conditioned
ciple,— the law of Rea- , i t • i ^^^ • i
■on and Consequent ^^ consequent be denied, so likewise must be
the condition or antecedent. But this is mani-
festly nothing else than the law of Sufficient Reason, or of Reason
and Consequent." ^ The principle of this syllogism is thus variously
enounced, — JPosita conditioner ponitvr conditionatvm ; sublato
conditionato, tollitur conditio. Or otherwise, —
How enonnced. • . i . ...
A rattone ad rationatum, a negatione rationutt
ad negationem ratio7iis, valet consequentia. The one alternative of
either rule being regulative of modus ponens^ the other of the modus
toUens?
" But here it may be asked, why, as we conclude from the truth
of the antecedent to the truth of the consequent
Why we cannot con- (^ ratione ad rationatum), and from the false-
c u e rom e ru hood of the Consequent to the falsehood of the
of the consequent to ^
the truth of the ante- antecedent (a negatione rationati ad negatio-
cedent, and from the ncm, vatiotiis)., Can wc not couverscly conclude
falsehood of the ante- ^^^^ ^^^ ^^^^^ ^^ ^j^^ Consequent to the truth
cedent to the false- ,01,1/.,
hood of the oonse- of the antecedent, and from the falsehood of the
^nent antecedent to the falsehood of the consequent?
In answer to this question, it is manifest that
this could be validly done, only on the following supposition,
namely, if every consequent had only one possible antecedent ; and
if, from an antecedent false as considered absolutely and in itself, it
were impossible to have consequents true as facts.
"Thus, in the first place, it is incompetent to conclude that be-
cause B exists, that is, because the consequent member of the sump-
tion, considered as an absolute proposition, is true, therefore the
supposed reason A exists, that is, therefore the alleged antecedent
member must be true ; for B may have other reasons besides A,
such as C or D. In like manner, in the second place, we should
not be warranted to infer, that because the sui)posed reason A is
unreal, and the antecedent member filse, therefore the result B is
also unreal, and the consequent member false; for the existence of B
might be determined by many other reasons than A.'" For example:
If there are sharpers in the company, ux ought not to gambte;
But there are no sharpers in the company;
Therefore, we ought to gamble,
lEMer.Log^O:. {91,p.l74.— Ed. t S««Kant, Lo^ H 7S,76. Krjxg, Legik, i SI. —'Ed
8 Krug, Logik, ) 82, p. 256. — Ed.
■f^
Lkct. XVm. LOGIC. 248
Here the conclusion is as false as if we conversely inferred, that
because we oxight not to gamble^ the)'e are no sharpers in the room.
" Logicians have given themselves a world of pains in the dis-
covery of general rules for the conversion of
Conversion of Hy- Hypothetical Syllogisms into Categorical.^ But,
pothetica to ategor- j^ ^^^ g^,^^ place, this is Unnecessary, in so far as
ical Syllogisms, is 1°, * ' . . '
Unnecessary. it is applied to manifest the validity of an hypo-
thetical syllogism; for the hypothetical syllo-
gism manifests its own validity with an evidence not less obtrusive
than does the categorical, and, therefore, it stands in no need of a
reduction to any higher form, as if it were of this a one-sided and
accidental modification. With equal propriety might we inquire,
how a categorical syllogism is to be converted into an hypothetical.
In the second place, this conversion is not
21^, Not a ways pes- always possible, and, therefore, it is never ne-
cessary. In cases where the sumption of an
hypothetical syllogism contains only three notions, and where, of
these three notions, one stands to the other two in the relation of
:i middle term, — in these cases, an hypothetical syllogism may
without difficulty be reduced to categoricals. Thus, when the
formula — -5^ A is, then B is, signifies — If ^ is C, then A is also B;
that is,' A is B, inasmuch as it is C ; — in this case the categorical
form is to be viewed as the original, and the hypothetical as the
derivative."^ For example:
If Caius be a man, then he is mortal;
But Caius is a man ;
Therefore, he is mortal
Here the notion man is regarded as comprehending in it, or a«
contained under, the notion mortal; and as being comprehended
in, or as containing under it, the notion Caius ; it can, therefore,
serve as middle term in the categorical syllogism to connect the
two notions Caius and mortal. Thus :
Man is mortal;
Caius is a man ;
Therefore, Caius is mortal.
1 [For the reduction of hypotheticals, see see Krug, Logik, p. 356, and Lexikon, iii. p
Wolf, Philos. Rat., § 412. Reusch, Systema 559. Fries, Logik, § 62, p. 267. Baclimana
Logicum, § 663. HollDaeus, EUmenta Logica, Logik, § 89, Anm. 2. (In part), Aristotle,
L. i. tract, iii. c. 1, p. 95. Keckermann, Opera, Anal. Prior., L. i. c. 44, p. 274, ed. Pacii.. (lu
t. i. pp. 266, 767. Crellius, Isagoge, L. iii. c. part), Pacius, Tn Arist., Organon, loc. eit-, p
17, p. 243 Kiesewetter, Allgemeine Logik, i. 194]
♦ 239, p. 115. Esser, Z.og^iAr, §§ 99, 100. Against, 2 Krug, I.og^ii, p. 268, Anm, 3. — Ed.
S44 LOGIC. Lkct. xvm.
" In such cases it requires only to discover the middle term, in
order to reduce the hypothetical syllogism to a categorical form;
and no rules are requisite for those who comprehend the nature of
tlie two kinds of reasoning.
"But in those cases where the gumption of an hypothetical syllo-
gism contains more than three notions, so that the formula, If K
iSy then B is^ signifies, If A is C, then is B also D, — in such cases,
an easy and direct conversion is impossible, as a categorical syllo-
gism admits of only three principal notions. To accomplish a
reduction at all, we must make a circuit through a plurality of cat-
egorical syllogisms before we can ariive at an identical conclusion,
— a process which, so far from tending to simplify and explain, con-
duces only to pei-plex and obscure.^
" On the other hand, we can always easily convert an h j-potheti-
cal syllogism of one form into another, — the
Hypothetical syiio- modus ponens into the modus toUeiis, — the
^TT ° °?lx TT modus tollens into the modus ponens. This is
Muily convertible into , , ^
tbat of another. done by a mere contraposition of the antece-
dent and consequent of the sumption. Tb'is,
the Ponent or Constructive Syllogism :
^ Socrates be virtmua, then he merits «tleem { • ■
But Socrates is virtuoas ;
Therefore, he merits esteem, ^
may thus be converted into a ToUent or Destructive syllogism :
Jff' Socrates do not merit esteem, then he is not virtuous;
But he is virtuous ;
Tker^re, he merits esteem.
"This latter syllogism, though apparently a Constructive syllc
gism, is in reality a Destructive. For, in modo ponente, we con-
clude from the truth of the antecedent to the truth of the conse^
<quent; but here we really conclude from the falsehood of the
consequent to the falsehood of the antecedent."* This latter syl-
logism, if fully expressed, would indeed be as follows :
If Socrates do not merit esteem, he is not virtuous;
But Socrates is not not virtuous ;
Therefore, he does not not merit estesm.
1 Compare Mark Duncan, Jnstit. Leg., L. It. [Boliano, WtastnteA^/tsMrt, L»gik, IL tHK, p^
«. 6, i 4, p. 240 et seq. Derodon, Logica Re»li- 662.]
(iita,Z)« Jr^m«n<«iion«, i lOG, p. 67S. — Ed. * Kmg, Logik, p. Wd,2B0. — KD.
I,KCT. xvm. LOGIC. 246
3**. I now go on to ^ statement and consideration of the special
rales by which an hypothetical syllogism is governed.
Par. Lxvi. 3o, spe- ^ LXVI. The spccial rules by which an
oiai Kuies of Hypo- Hypothetical Syllogism is regulated are the
thetloal SyllogiBm. . - » o
following;
I. A regular and peifect hypothetical syllogism must have three
propositions, in which, however, more than three principal
notions may be found.
H. The Sumption is, in regard to quantity and quality, uniform,
being always Definite and Affirmative ; whereas the Subsurap-
tion. varies in both relations.
III. The Conclusion is regulated in quantity and quality by that
member of the sumption which is not subsumed; in modo
ponente^ they are congruent; in modo toUente, they are opposed.'
"The question touching the special laws of the hypothetical syl-
logism, or, what is the same thing, the question
Buie.^ Thto reguiatl touching the original and necessary form of the
the general form of hypothetical syllogism, as determined by itfi
the hypothetical syiio- general principle, — the law of Reason and
Consequent, — this question may be referred
both to the whole reasoning and to its several parts. The original
and necessary form of the hypothetical syllogism, as determined by
its general principle, we have already considered- From this, as
already noticed, it follows as a corollary, that the hypothetical, like
every other syllogism, must contain a threefold judgment: 1°, A
judgment whose constituent members stand to each other in the
relation of reason and consequent; 2°, A judgment which sub-
sumes as existent, or non-existent, one or other of these constituent
members, standing to each other in the relation of reason and con-
sequent; and, 3°, Finally, a judgment decisive of the existence or
non-existence of that constituent member which was not subsumed
in the second judgment. In these three propositions — sumption,
subsumption, and conclusion — there may, however, be found move
than three principal notions ; and this is always the case when tii©
8ura[)tion contains more than three principal terms, as is exemplified
in a proposition like the following : Jf God reward virtue, then will
virtuous men be also happy. Here, however, it must, at the same
time, be understood, that this proposition, in which a larger plural-
ity of notions than three is apparent, contains, however, only the
1 Krag, Z.ogii, J 83. — Ed.
246
LOGIC.
lect. xvni
Ground on which
the Hypothetical Syl-
logism has been re-
garded as having only
two terms and two
propositions.
This view erroneous.
thought of one antecedent and of one consequent; for a single con-
sequent supposes a whole antecedent, how complex soever it may
be, and a single antecedent involves in it a whole consequent,
though made up of any number of parts. Both of these possibili-
ties are seen in the example, now adduced, of an hypothetical judg-
ment, in which there occur more than three principal notions. I^
however, an hypothetical proposition involve
only the thought of a single antecedent and
of a single consequent, it will follow that any
hypothetical syllogism consists not of more th;:ii
three, but of less than three, capital .notions;
and, in a rigorous sense, this is actually the
case."* On this ground, accordingly, some logicians of great acute-
ness have viewed the hypothetical syllogism as a syllogism of two
terms and of two propositions."* This is, how-
ever, eiToneous ; for, in an hypothetical syllo-
gism, there are virtually three terms." "That under this form of
reasoning a whole syllogism can be evolved out of not more than
two capital notions depends on this, — that the two constituent
notions of an hypothetical syllogism present a character in the
sumption altogether different from what they exhibit in the sub-
sumption and conclusion. In the sumption these notions stand
bound together in the relation of reason and consequent, without,
however, any detennination in regard to the reality or unreality of
one or other; if one be, then the other is, is all that is enounced.
In the subsumption, on the other hand, the existence or nou-exist-
ence of what one or other of these notions comprises is expressly
asserted, and thus the concept, expressly affirmed or expressly de-
nied, manifestly obtains, in the subsumption, a wholly different sig-
nificance from what it bore when only enounced as a condition of
reality or unreality ; and, in like manner, that notion which the sub-
sumption left untouched, and concerning whose existence or non-
existence the conclusion , decides, obtains a character altogether
different in the end from what it presented in the beginning. And
thus, in strict propriety, there are found only three capital notions
in an hypothetical syllogism, namely, 1°, The notion of the recipro-
cal dependence of subject and predicate, 2", The notion of the
reality or unreality of the antecedent, and, 3°, The notion of the
reality or unreality of the consequent."' So much in explanatiou
1 Esser, Logii, f 92, p. 175-6. — Ed.
S See Kant, Logik, ) 75. Kant's view is
combatted by Krug, Logik, i 83.— Ed. [A
view similar to that of Kant is held by Weiss,
Logik, M 210, 251. Herbart, Logik, } 6S. Fl»
Cher, Logik, i 100, p. 137.]
s Eaier, foe. «(. — Ed
Lkct. xviii. logic. 247
of the first special law, or that regulative of the general form of the
hypothetical syllogism.
The second law states the conditions of these two premises, —
that the sumption, in reference to its quantity
Second Rule. r^ • -r u • i ^ £ •/
and quality, is unitorm, being always dennite,
that is, singular or universal, and affirmative ; while the subsump-
tion, in both relations, remains free.
In regard to the sumption, when it is said that it is always defi-
nite, that is, singular or universal, and affirma-
That the sumption tive, this must be understood in a qualified
18 always definite to mi-.i^ •. •i-ii
. J.J- sense. 1 ouching the former, it may indeed be
be understood in a _ cj ' .'
qualified sense. Said that quantity may be altogether throsvn
out of account in an hypothetical syllogism.*
For a reason being once supposed, its consequent is necessarily
affirmed without limitation ; and, by tlie disjunction, the extension
or comprehension of the subject is so defined, that the opposite
determinations must together wholly exhaust it. It may, indeed,
sometimes appear as if what was enounced in an hypothetical sump-
tion were enounced only of an indefinite number, — of some ; and
it, consequently, then assumes the form of a particular proposition.
For instance. If' some men are virtuous, then some other men are
vicious. But here it is easily seen that such judgments are of an
universal or exhaustive nature. In the proposition adduced, the
real antecedent is. If some men {only) are virtuous ; the real con-
sequent is, then all other men are vicious. It Avould, perhaps, have
been better had the relative totality of the major proposition of a
hypothetical syllogism been expressed by another term than univer-
sal? For the same reason it is, that the difierence of extensive and
comprehensive quantity determines no external change in the ex-
pression of an hypothetical syllogism ; for every hypothetical syllo-
gism remains the same, whether we read it in the one quantity or
in the other.
In regard to the other statement of the rule, that the sumption
of an hypothetical syllogism must be always
That the sumption is «? .• ^i • ti • i i j i»
_ .. affirmative, — this, likewise, demands a word of
always affirmative. ' ' '
illustration. It is true that the antecedent or
the consequent of such a sumption may be negative as well as
affirmative ; for example. If Caius he not virtnaus, he is not entitled
to respect; If the sun be not risen, it is not day. But here the
1 [See Alexander Apbrodisiensis, In Anal. 2 See above p. 188. Compare Esser, lagtk.
Prior., f. 5 a. Scholia, ed. Brandis, p. 144. § 92, p. 177. — Ed.
Dcrodon, Logica Rmtitvta, p, 688.] [Compare
above, pp. 188, 236. — Ed.]
li4S LOGIC. Lkct. xvia
jjroposition, as an hypothetical judgment, is and must be affirmative.
For the affirmative in such a judgment is contained in the positive
assertion of the dependence of consequent or antecedent ; and if
such a dependence be not affirmed, an hypothetical judgment can-
not exist.
In regard to what is stated in the rule concerning the conditions
of the subsumption, — that this may either bo
The subsumption. , • ^ n- •
general or particular, amrmative or negative, —
it will not be requisite to say anything in illustration. For, as the
Hubsuinption is merely an absolute assertion of a single member of
the sumption, and as such member may, as an isolated j)roposition,
be of any quantity or any quality, it follows that the subsumption
is equally unlimited.
• In reference to the third rule, which states that the conclusion is
regulated in quantity and quality by that mem-
ber of the sumption which is not subsumed, and
this in modo ponente by congruence, in modo toUetUe by opposition,
it will not be requisite to say much.
♦*In the conclusion, the latter clause of the sumption is affirmed
in modo ponente^ because the former is affirmed in the sub8um])tion.
In tliis case, the conclusion has the same quantity and quality as the
clause which it affirms. In modo tollente the antecedent of the
sumption is denied in the conclusion, because in the subsumption
the consequent clause had been denied. There thus emerges an
opposition between that clause, as denied in the conclusion, and
that clause as affirmed in the sumption. The conclusion is thus
always opposed to the antecedent of the sumption in quantity, or
in quality, or in both together, according as this is diflerently deter-
mined by the diffiarent constitution of the propositions. For
example :
Jtr some men were omniscient, dim would Ouy be as Oods ;
BtU no man is a God ;
Therefore, some men are not omnitcieni, that is, no man is omniscient."^
- 1 now proceed to the consideration of the last class of syllogisms
a Hypothetico-diiH affiii'dod by the Intemal Form, — the class of
juDctive or Diiem- Dilenunatic or Hypothetico-disjunctivo SyUo*
matic Syllogisms. gisms, and I comprise a general enunciatlop of
their nature in the following paragraph.
1 Krag, Logik, i 83, p. a6& -^Ep.
Lect. XVIII. LOGIC. 249
^ LXVII. If the sumption of a syllogiRra he at once hypo-
thetical and disjunctive, and if, in the sub-
pothetioo-disjuaotive suuiption, the wholc disjuuctioH, as a conse-
Byiiogism or Di- qucut, be sublatcd, in order to sublate tlie
^™™** antecedent in the conclusion ; such a rea-
soning is called an Hypothetico-disjunctive /SyUogism, or a
Dilemma. The form of this syllogism is the following :
If A exist, then either B or C exists f
But neither B nor C exists ;
Therefore, A does not exist.^
We have formerly seen that an hypothetical may be combined
. with a disjunctive judgment; and if a proposi-
tion of such a character be placed at the head
of a reasoning, we have the Hypothetico-disjunctive Syllogism or
Dilemma. This reasoning is properly an hypothetical syllogism, in
which the relation of the antecedent to the consequent is not abso-
lutely affirmed, but affirmed through opposite and reciprocally ex-
clusive predicates. J^ A exist, then either B or C exist. The
sumption is thus at once hypothetical and disjunctive. The sub-
sumption then denies the disjunctive members contained in the con-
sequent or posterior clause of the sumption. J8ut neither B nor C
exist. And then the inference is drawn in the conclusion, that the
reason given in the antecedent or prior clause of the sumption must
likewise be denied. Therefore A does not exist.^ For example ;
Jf man he not a morally responsible being, he jnust tcant either the power of recognizing
moral good (as an intelligent agent), or the power of willing it (as a free agent).
But man wants neither the power of recognizing moral good (as an intelligent agent), nor
the power of wiUyig it (as a free agent) ;
Therefore, man is a morally responsible being.
"An hypothetico-disjunctive syllogism is called the dilemma or
hotted syllogism, in the broader acceptation of
Designations of the i}^q term (dilem,ma, ceraXimts, comutus sc. syllo-
xiyTs,yVo^\sm. gismus). We must not, however, confound the
cornutus and crocodilinus of the ancients with
our hypothetico-disjunctive syllogism. The former were sophisms
of a particular kind, which we are hereafter to consider; the latter
1 Kriig, Logik, ( 87. — Ed. [Contra, see 257. Aldrich, Rurfimenm Z-og^icff, c. iv. $ 3, p.
Troxler, iog^.i, ii. p. 103 n*. That the Dilem- 107, Oxford, 1852. riatner, PMlosophUch*
ma is a negative induction, see Wallis, Lo^iea, Aphorismen, i. } 5S3, p. 280.]
L. Hi. c. 19, p. 218. Cf. Fries, Logik, § 60, p. 2 Krug, toe. rit. — Ed.
32
250 LOGIC. Lect. XVIII.
is a regular and legitimate form of reasoning. In regard to the
application of the terms, it is called the cornutus or horned syllo-
gism, because in the sumption the disjunctive members of the con-
sequent are opposed like horns to the assertion of the adversary ;
with these, we throw it from one side to the other in the subsump-
tion ; in order to toss it altogether away in the conclusion. If the
disjunction has only two members, the syllogism is then called a
dilemma (bicortiis) in the strict and proper signification, literally
double sumption. Of this the example previously given is an in-
stance. If it has three, four, or five members, it is called trilemma
(tricomis), tetralem,ma (quadrncortiis), pentalemma (qmtiquecomis) ;
if more than four, it is, however, usually called polylemma (multi-
comis). But, in the looser signification of the word. Dilemma is a
generic expression for any or all of these."*
"Considered in itself, the hypothetico-disjunctive syllogism is not
to be rejected, for in this form of reasoning we
u eg for sifting a ^^^ conclude with cosTency, provided we attend
proposed Dilemma. '^ -i ' r
to the laws already given in regard to the hypo-
thetical and disjunctive syllogisms. It is not, however, to be de-
nied, that this kind of syllogism is very easily abused for the purpose
of deceiving, through a treacherous appearance of solidity, and from
terrifying a timorous adversniry by its horned aspect. In the sifting
of a proposed dilemma, we ought, therefore, to look closely at the
three following particulars: — 1°, "Whether a veritable consequence
subsists between the antecedent and consequent of the sumption ;
2°, Whether the opposition in the consequent is thorough-going and
valid ; and, 3", "Whether in the subsumption the disjunctive mem-
bers are legitimately sublated. For the example of a dilemma
which violates these conditionsi, take the following :
jfjr virtue xoere a habit worth acquiriry, it must insure either j^pwer, or wealth, or honor,
or pleasure ;
But virtue insures none of these ;
Ther^ore, virtue is not a habit worth attaining.
" Here : — 1°. The inference in general is invalid : for a thing may
be worth acquiring, though it does not secure any of those advanta-
ges enumerated. 2°. The disjunction is incomplete; for there are
other goods which virtue insures, though it may not insure those
here opposed. 3°. The subsumption is also vicious ; for virtue has
frequently obtained for its possessors the very advantages hero
denied." »
1 Kin^'./o(r cit. Anm..2. — Ed. (Cf. Keck- < Krug, Logik, J 87. Anm 8, p. 281 -
ermauii, Optra, t. i. pp. 26S, 76!) ] Ed.
Lect. XVm. LOGIC. 251
Before leaving this subject, it may be proper to make two obser-
vations. The first of these is, that though it has
Tbe whole of the been Stated that Categorical Syllogisms are gov-
logicai iawB,-iden- ^^.^^^ , the'laws of Identity and Contradic-
tity, Contradiction, •' *'
Excluded Middle, and tion, that Disjunctive Syllogisms are governed
Reason and Conee- by the law of Excluded Middle, and that Hypo-
quent.-are operative thetical Syllogisms are governed by the law
in each form of syllo- . _ i ^ , .
jgjjj 01 Keason and Consequent, — this statement
is not, however, to be underetood as if, in these
several classes of syllogism, no other law were to be found in
operation except that by which their peculiar form is determined.
Such a supposition would be altogether erroneous, for in all of tliese
difierent kinds of syllogism, besides the law by which each class is
principally regulated, and from which it obtains its distinctive char-
acter, all the othera contribute, though in a less obtrusive manner, to
allow and to necessitate the process. Thus,
This illustrated though the laws of Identity and Contradiction
. n a egonca ^^.^ ^y^^ laws which preeminently regulate the
Syllogisms. ^ ^ ^ . .
Categorical Syllogism, — still without the laws
of Excluded Middle, and Reason and Consequent, all inference in
these syllogisms would be impossible. Thus, though the law of
Identity affords the basis of all affirmative, and the law of Contra-
diction the basis of all negative, syllogisms, still it is the law of
Excluded Middle which legitimates the implication, that, besides
affirmation and negation, there is no other possible quality of predi-
cation. In like ma^jner, no inference in categorical reasoning could
be drawn, were we to exclude the determination of Reason and
Consequent. For we only, in deductive reasoning, conclude of a
part what we assume of a whole, inasmuch as we think the whole as
the reason, — the condition, — the antecedent, — by which the part,
as a consequent, is determined ; and we only, in inductive reason-
ing, conclude of the whole what we assume of all the parts, inasmuch
as we think all the parts as the reason, — the condition, — the ante-
cedent, — by which the whole, as a consequent, is determined. In
point of fact, logically or formally, the law of
The law of Identity Identity and the law of Reason and Consequent
formally the same with j^^ j^^ affirmative form, are at bottom the same;
that of Reason and ■, • • /•
Consequent *"® ^^^ of Identity Constitutes only the law of
Reason and Consequent, — the two relatives
being conceived simultaneously, that is, as subject and predicate ;
the law of Reason and Consequent constitutes only the law of
Identity, the two relatives being conceived in sequence, that is, as
252 LOGIC. Lbct. XVIII.
.antecedent and consequent.^ And as the law of Reason and Con-
Kcquent, in its positive form, is only that of Identity in movement;
kio, in its negative form, it is only that of Contradiction in movement.
In Disjunctive Syllogisms, again, though the law of Excluded
Middle be the principle which bestows on them
2. In Disjuncuve Syi- ^j^^j^. yii^r form, Still these syllogisms are not
independent of the laws of Identity, of Contra-
diction, and of Reason and Consequent. The law of Excluded
Middle cannot be conceived apart from the laws of Identity and
Contradiction ; these it implies, and, without the principle of Reason
and Consequent, no movement from the condition to the condi-
tioned, that is, from the affirmation or negation of one contradictory
to the affirmation or negation of the other, would be possible.
Finally, in Hypothetical Syllogisms, though the law of Reason
and Consequent be the prominent and distinc-
3 In Hypothetical ^j^.^ principle. Still the laws of Identity, Contra-
Syllogisms. .
diction, and Excluded Middle are also there at
work. The law of Identity affords the condition of Affirmative or
Constructive, and the law of Contradiction of Negative or Destruc-
tive, Hypotheticals ; while the law of Excluded Middle limits the
reasoning to these two modes alone.
The second observation I have to make, is one suggested by a
difficulty which has been proposed to me in
Difficulty in regard ^^ ^^j ^^ ^j^^ doctiine, that all reasoning is
to the doctrine, that . /.
all reasoning is either either from whole to part, or from the parts to
from whole to part or the wholc. The difficulty, which oould only
from the parts to the j^j^^e presented itself to an acute and observant
whole, — obviated. . ,, . i • /• • i
intellect, it gave mo much satisfaction to hear
proposed ; and I shall have still greater gratification, if I should
be able to remove it, by showing in what sense the doctrine
advanced is to be understood. It was to this effect: — In Cate-
gorical Syllogisms, deductive and inductive, intensive and exten-
sive, the reasoning is manifestly from whole to part, or from the
parts to the whole, and, therefore, in regard to the doctrine in
question, as relative to categorical reasoning, there was no difficulty.
But this was not the case in regard to Hypothetical Syllogisms.
These are governed by the law of Reason and Consequent, and it
docs not appear how the antecedent and consequent stand to each
other in the relation of whole and pafrt.
In showing how the reason and the conseqaent are to be viewed
as whole and pait, it is necessary, first, to repeat, that the reason
I [Compare Kappen, Daruettung de$ Watn* dtr PhilosopU*, p. 102 « J(f ., NUmberg, 1810.|
Lect. XVIlt LOGIC. 25^
or antecedent means tlie condition^ that is, the complement of all,
without which something else would not be;
This difficulty con- a^f] \\^q consequent means the conditioned, that
.idered with respect j ^,^^ complement of all that is determined to
to Hypothetical 8jllo- , , ^, -^ r ^, • , v
jj,jpg be by the existence of something else. You
Antecedent and Con- must further bear in mind, that we have nothing
81-quent are equal to ^^ ^(j ^.j^}^ things Standing in the relation of
Condition and Condi- , ^ , • ^ i
jj^j^g^ reason and consequent, except in so lar as they
are thought to stand in that relation ; it is with
the ratio co^noscendi, not Avith the ratio essendi, that we have to
do in Logic ; the former is, in fact, alone properly denominated
reason and consequent, while the latter ought to be distinguished
as cause and effect. The ratio essendi, or the law of Cause and
Effect, can indeed only be thought under the form of the ratio cog-
noscendi, or of the principle of Reason and Consequent ; but as the
two are not convertible, inasmuch as the one is far more extensive
than the other, it is proper to distinguish them, and, therefore, it is
to be recollected, that Logic is alone convereant with the ratio cog-
noscendi, or the law of Reason and Consequent, as alone conversant
with the form of thought.
This being underetood, if the reason be conceived as that which
conditions, in other words, as that which con-
Hence the reason or ^.^j^g ^^^ necessity of the existence of the con-
condition must con- . . . . ... . ,
tain the consequent. Sequent; It IS evident that it is conceived as
containing the consequent. For, in the first
place, a reaaon is only a reason if it be a sufficient reason, that is, if
it comprise all the conditions, that is, all that necessitates the exist-
ence, of the consequent; for if all the conditions of anything arc
present, that thing must necessarily exist, since, if it do not exist,
then some condition of its existence must have been wanting, that
is, there was not a sufficient reason of its existence, which is con-
trary to the supposition. In the second place, if the reason, the
sufficient reason, be conceived as comprising all the conditions of
the existence of the consequent, it must be conceived as comprising
the consequent together; for if the consequent be supposed to con-
tain in it any one part not conceived as contained in the reason, it
may contain two, three, or any number of parts equally uncontained
in the reaaon, consequently it may be conceived as altogether un-
contained in the reason. But this is to suppose that it has no
reason, or that it is not a consequent; which again is contrary to
the hypothesis. The law of Reason and Consequent, or of the
Condition and the Conditioned, is only in fact another expression
of Aristotle's law, that the whole is necessaiily conceived aa prior
254
LOGIC.
Lect. XVIIl
The Law of Reason
and Consequent only
another expression of
Aristotle's law. that
the whole is necessa-
rily conceived as prior
to the part.
Aristotle's law criti-
cized.
Whole and Parts re-
»pectively may be
viewed in thought
either as the condi-
tioning or as the con-
ditioned.
to the part, totum parte prius esse, necesse est} It is, however,
more accurate ; for Aristotle's law is either
inaccurate or ambiguous. Inaccurate, for it is
no more true to say that the whole is necessarily
piior in the order of thought to the parts, than
to say that the parts are necessarily prior in the
order of thought to the whole. Whole and
parts are relatives, and as such are necessarily
coexistent ir. thought. But while eaclf implies
the other, and the notion of each necessitates
the notion of the other, we may, it is evident, view either, in
thought, as the conditioning or antecedent, or as
the conditioned or consequent. Thus, on the one
hand, we may regard the whole as the prior and
determining notion, as containing the parts, and
the parts as the posterior and determined notion,
as contained by the whole. On the other hand,
we may regard the parts as the prior and determining notion, as con-
stituting the whole, and the whole as the posterior and determined
notion, as constituted by the parts.* In the former case, the whole is
thought as the reason, the parts are thought as the consequent; in
the latter, the parts are thought as the reason, the whole is thought as
the consequent. Now, in so far as the whole is thought as the rea-
son, there will be no difficulty in admitting that the reason is con-
ceived as containing the parts. But it may be asked, how can the
parts, when thought as the reason, be said to contain the whole?
To this the answer is easy. All the parts contain the whole, just as
iViuch as the whole contains all the parts. Objectively considered,
the whole docs not contain all tlie parts, nor do all the parts con-
tain the whole, for the whole and all the parts are precisely equiva-
lent, absolutely identical. But, subjectively considered, that is,
as mere thoughts, we rnay either think the whole by all the parts,
or think all the parts by the whole. If we think all the parts by
the whole, we subordinate the notion of the parts to the notion of
1 Mftaphyfics, iv. 11. Aristotle, however,
allows a double relation. The whole, when
conceived as actually constituted, must be
regarded as prior to the parts; for the latter
only exist as parts in relation to the whole.
Potentially, however, the parts may be re-
garded as prior; for the whole might be
destroyed as a system without the destruction
of the parts. Where the whole is not con-
ceived as actually constituted, this relation is
reversed. Thus Ariittotle'B rule may be re-
garded as coextensive with that given in the
text. See the next note. — Ed.
2 This is substantially expressed by Aris-
totle, I. c, whose distinction is applicable
either to the order of thought or to that of
existence, tcarii yiy*<riy (i. «., regarded as a
complete system), the whole is actually, the
parts arc only potentially, existent ; while, on
the other hand, iforol (ft^opdy (i. c, regarded
as disorganized elements), the parts exist ac-
tually, the whole only potentially. — Kd.
Lect. xviii. logic. 255
the whole ; that is, we conceive the parts to exist, as we conceive
their existence given through the existence of the whole containing
them. If we think the whole by all the parts, we subordinate the
notion of the whole to the notion of the parts ; that is, we conceive
the whole to exist, as we conceive its existence given through the
existence of the parts which constitute it. Now, in the one case,
we think the whole as conditioning or comprising the parts, in the
other, the parts as conditioning or comprising the whole. In the
former case, the parts are thought to exist, because their whole
exists ; in the latter, the whole is thought to exist, because it§ parts
exist. In either case, the prior or determining notion is thought to
comprise or to contain the posterior or deter-
Appiication of this mined. To apply this doctrine: On the one
doctrine to the solu- , j • . , , 11 .^
r *.. j«i 1* hand, every science is true only as all its sev-
lion of the difficulty ^ J ...
previously stated. eral rules are true ; in this instance the science
is conceived as the determined notion, that is,
as contained in the aggregate of its constituent rules. On the
other hand, each rule of any science is true only as the science
itself is true ; in this instance the rule is conceived as the deter-
mined notion, that is, as contained in the whole science. Thus,
every single syllogism obtains its logical legitimacy, because it is a
consequent of the doctrine of syllogism ; the latter is, therefore,
the reason of each several syllogism, and the whole science of
Logic is abolished, if each several syllogism, conformed to this doc-
trine, be not valid. On the other hand, the science of Logic, as a
whole, is only necessary inasmuch as its complementary doctrines
are necessary ; and these are only necessary inasmuch as their indi-
vidual applications are necessary; if Logic, therefore, as a whole, be
not necessary, the necessity of the parts, which constitute, deter-
mine, and comprehend that whole, is subverted. In one relation,
therefore, reason and consequent are as the whole and a contained
part, in another, as all the parts and the constituted or comprised
whole. But in both relations, the reason — the determining notion
— is thought, as involving in it the existence of the consequent or
determined notion. Thus, in one point of view, the genus is the
determining notion, or reason, out of which are evolved, as conse-
quents, the species and individual; in another, the individual is the
determining notion or reason, out of which, as consequents, are
evolved the species and genus.^ In like manner, if we regard the
subject as that in which the attributes inhere, — in this view the
subjept is the reason, that is, the whole, of which the attributes are
1 This is expressly allowed by Aristotle, W. Hamilton liimself, Discussions, p. 178. —
Metnph , iv. 25, and is quoted from I'.im by Sir Ed.
256
LOGIC.
Lbct. xvm
a part ; whereas if we regard the attributes as the modes through
which alone the subject can exist, in this view the attributes are
the reason, that is, the whole, of which the subject is a part. In a
woi"d, whatever we think as conditioned, we think as contained by
something else, that is, either as a part., or as a constituted whole ;
whatever we think as conditioning, we think either as a containing
whole, or as a sum of constituting parts. What, therefore, the
sumption of an hypothetical syllogism denotes, is simply this : If A,
a notion conceived as conditioning, and, therefore, as involving B,
exist, then B also is necessarily conceived to exist, inasmuch as it is
conceived as fully conditioned by, or as involved in, A, I am afraid
that what I have now said may not be found to have removed the
difficulty, but if it suggest to you a train of reflection which may lead
you to a solution of the difficulty by your own eflfort, it will have
done better.
So much for Hypothetico-disjunctive syllogisms, the last of the
four classes determined by the internal form of reasoning. In these
four syllogisms, — the Categorical, the Disjunctive, the Hypothet-
ical, and the Hypothetico-disjunctive, — all that they exhibit is con-
formable to the necessary laws of thought, and they are each dis-
tinguished from the other by their essential nature ; for their
sumptions, as judgments, present characters fundamentally differ-
ent, and from the sumption, as a general rule, the validity of syllo-
gisms primarily and principally depends.
LECTURE XIX.
STOIOHEIOLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT
III. — DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO EXTERNAL
FORM.
A. COMPLEX, — EPICHEIREMA AND SORITES.
In* our treatment of Syllogisms, we have hitherto taken note only
of the Internal, or Essential Form of Reason-
syiiogisms, - their ■ g^^ besides this internal or essential form,
External Form. & ' , . . ,
there is another, an External or Accidental
Form ; and as the former was contained in the reciprocal relations
of the constituent parts of the syllogism, as determined by the
nature of the thinking subject itself, so the latter is contained in the
outer expression or enouncement of the same parts, whereby the
terms and propositions are variously affected in respect of their -
number, position, and order of consecution. The varieties of Syl-
logism arising from their external form may, I think, be con-
veniently reduced to the three heads expressed in the following:
paragraph :
if LXVm. Syllogisms, in respect of their External Form,
admit of a threefold modification. For
Par. IiXVm. Divi- i.-i ,■. . o- 7
8ioa of Syllogisms ac- ^^^^6, as purc, they are at once Simple,
cording to External and Complete, and Regular, so, as quali-
°''"' fied, they are either Com,plex, or Income-
plete, or Irregular; the two former of these modifications
regarding the number of their parts, as apparently either too
many or too few ; the last regarding the inverted order in
which these parts are enounced.
S8
258 LOGIC. Lect. XIX
I shall consider these several divisions in their
ExpUcaUon. order ; and, first, of the syllogisms which vary
A. Complex SyUo- ^ \ . , „ / • , , .
giga^ fi'om the simple form of reasoning by their
apparent complexity.
But, before touching on the varieties of syllogism afforded by
their apparent complexity of composition, it
ation o y o- ^jjjjy be proper to premise a few words in re-
giams to each other. *' ' "^ _ •
gard to the Illation of syllogisms to each other.
"Every syllogism may be considered as absolute and independent,
inasmuch as it always contains a complete and inclusive series of
thought. But a syllogism may also stand to other syllogisms in
sach a relation that, along with these correlative syllogi^ii> it
makes up a greater or lesser series of thoughts, all holding to each
other the dependence of antecedent and conseqnent. And such a
reciprocal dependence of syllogisms becomes necessary, when one
or other oi the predicates of the principal syllogism is destit«te of
complete certainty, and when this certainty must be established
through one or more correlative syllogisms."^ "A syllo^sm, viewed
as tin isolated and independent whole, is called
Classes and desig- a MonosyUogtsm {monosyllogismus), that is, a
DaUons of related syi- gj^jrle i^asoning ; whcfeas, a series of coTrelati\ e
logisms. Houo8yIIo- - '^ ^
gteth. syllogisms, following each other in the recipro-
„ , „ cal relat^fi of antecfedeat and conseqtient, is
Poljrsyllogistn, or ^
Chain of Reasoning. Called ^ PolysyUogism {polysyllogismus), thzX.
is, a multiplex or coinposite reasoning, and may
likewise be denominated a Chain of Reasoning (series syUogistica).
Such a chain —such a series — may, however, have such an order of
tde^endence, that cither each successive syllogism is the reason of
iJiat which preceded, of the preceding syllogism is the reason of
that which follows. Iti the former case, we con-
ABaiyUo Mid ^lude analytically or regressively ; in the second,
synthetically or progressively. That syllogism
in the series which contains the reasoning of the premise of another,
is called a Prosyllogisnt (prosyllogismus) ; and
Prosyiiogism. .jj^j^^ gyUogism which coTitatns the cotisequent of
Episyiiogism. another, is called an Episyllogis7n {episyUogiS'
mils). Eheiy Oiain of Reasoning must, there-?
fore, be made np both of Prosyllogisms and of Episyllogisms."'
'*When the series is composed of more than two syllogisms, the
58ame syllogism may, in different relations, be at once a prosyllogism
and an episyiiogism; and that reasoning which contains the primary
I EMer. Loftfc, }104. — £d. t£ rag I^vtlh fill. — Bd.
I
J^ifiCT. XIX. L 0<S I C . ^9
or highest reason 'is alone exclusively a prosyllogism, as that reason-
ing which enounces the last or low<?st consequent is alone exclu-
sively an episyllogism. But this concatenation of syllogisms, as
antecedents and consequents, may be either manifest, or occult,
according as the plurality of syllogisms may either be openly dis-
played, or as it may appear only as a single syllogism. The poly-
syllogism is, therefore, likewise either manifest or occult. The
occult polysyllogism, with which alone we are at present con-
cerned, consists either of partly complete and partly abbreviated
syllogisms, or of syllogisms all equally abbreviated. In the former
case, there emerges the complex syllogism called Epicheirema; in
the latter, the complex syllogism <;aUed Soritt&r^ Of these in
tlueir order.
T LXIX. A syllogism is now vulgarly called an Epichei-
rema (iinx^Lprjfia), when to either of the two
Par. liXIX. The . ^ i ^i .i_ • j
jEpiebeixema. premises, or to botfl, thens IS annexed a
reason for its support. As :
B is A;
But C is B; for it is J);
Thertfore, C is also A.2
Or,
All vice is odious ;
But avarice is a vice ; for it makes men slaves;
Thertfore, avarice is odious.^
In illustration of this paragraph, it is to be observed that the
Epicheirema, or Reason-rendering Syllogism,
is either single or double, according as one
or both of the premises are furnished with an auxiliaiy reason.
The single epicheii-ema is either an epicheirema of the first or sec-
ond order, according as the adscititious proposition belongs to the
sumption or to the subsumption. There is little or nothing requi-
•fiite to be stated in regard to this A'ai-iety of complex syllogism, as
it is manifestly nothing more than a regular episyllogism with an
abbreviated prosyllogism interwoven. There might be something
lEsser, Logik, § 104. — Ed. [Cf. Reusch, 3 In full,—
Sj/stema Logicum, § 578, p. 664, lenae, 1741.1 nr. . t j j ^^
' p . J., Bia avarice makes men slaves;
_ . _' Therefore, avarice is a vice.
D u B; . ^ ^
Thaxfore, C « B. v
260
LOGIC.
Lect. XLX.
said touching the name, which, among the ancient rhetoricians, was
used now in a stricter, now in a looser, signification.^ This, how-
ever, as it has little interest in a logical point of view, I shall not
trouble you by detailing ; and now proceed to a far more important
and interesting subject, — the second variety of complex syllo-
^sms, — the Sorites.
Par. XiXX. Tbe 80.
rites.
^ LXX. When, on the common principle of all reasoning,
— that the part of a part is a part of the
whole, — we do not stop at the second
gradation, or at the part of the highest
part, and conclude that part of the whole, — as All B is a part
of the whole A, and aU C is a part of the part B, therefore cUl C
is also a part of the whole A, — but proceed to some indefinitely
remoter part, as D, E, F, G, H, etc., which, on the general prin-
ciple, we connect in the conclusion with its remotest whole, —
this complex reasoning is called a Chain- Syllogism or Sorites.
If the whole from which we descend be a comprehensive quan-
tity, the Sorites is one of Comprehension ; if it be an extensive
quantity, the Sorites is one of Extension. The formula of the
first will be :
1) E u D; that is, E comprehends D;
2) D it C; that is, D comprehends C;
3) C 14 6; that is, C comprehends B;
4) B 15 A ; that is, B comprehends A ;
Thertfore, E is A; in other words, £ comprehends A.
The formula of the second will be :
1 ) B is A ; that is, A contains under U B ;
2) C is B; that is, B contains under it C;
3) D is C ; that is, C contains under it D;
4) E is D; that is, D contains under it E;
Therrfore, E i« A ; in other words, A contains under it E.
These reasonings are both Progressive, each in its several quan-
tity, as descending from whole to part. But as we may also, argu-
ing back from part to whole, obtain the same conclusion, there is
also competent in either quantity a Regressive Sorites. However,
I For some notices of these variations, see i 83; Facciolati, Aeroasrt, De Spiekirtmatt, p.
Qiilntilian, Imt. Oral , v. \0, 2, \ .14,5. Com- 127 etsftf. In Aristotle the term is uxetl for a
pare also Scliweigh«;user on Epictctus, i. 8; dialectic syllogism. See 7Vp*c«, Till. 11.—
Trcndeienburg, SUmenta Logicu AriMottUea, £d.
Lkct. XIX.
LOGIC.
26t
the formula of the Regressive Sorites in the one quantity, will be
only that of the Progressive Sorites in the other.^
Explication.
As a concrete example of these :
I. Progsessive Comprehensive Sorites.
Concrete examples
ot Sorites.
Or as explicated;
Bucephalus is a horse ;
A horse is a quadruped ;
A quadruped is an animal ;
An animal is a substance ;
Therefore, Bucephalus is a substance.
The representation of the individual Btuxphaius comprehends or contains in it tkt
notion horse ;
1 [On the Sorites in general, see Crakan-
tborpe, Logica,. L. iii. c. 22, p. 219. Valla,
Dialect., L. iii. c. 54, fol. 38, ed. 1509. M. Dun-
can, Instil. Log. L. iv. c. vii. § 6, p. 255. Fac-
ciolati, Acroases, De Sorite, p. 15 et seq. Me-
laiiclitlion, Erotem. Dial., L. iii. De Sorite, p.
74.3. Wolf, Phil. Rat., § 466, et seg. Walch,
i. -.rilcon. V. " Sorites." Fries, Logik, } 64.]
-' Diagrams Nos. 1 and 2 represent the afflr-
rautive Sorites in the casein which the con-
cepts are coextensive. — See above, p. 133,
Diagram 2. Diagrams Nos. 3 and 4 represent
the Affirmative Sorites in the case in which
the concepts are subordinate. — See above, p-
133, Diagram 3. Diagram No. 5, taken in
connection with No. 3, represents the Negi..-
tive Sorites. Thus, to take the Progressive
Comprehensive Sorites: — E is D, D is C, C
M B, B t« A, no A M P; there/ore, »o E is P. —
Ed.
SK" LOGIC. L«CT. XIX
T%e notitm hone comprehends the notion qaadruped ;
The notion quadruped cemprehends the iwtiim amnnU ;
The notion animal comprehends the notion substance;
Therefore (<m the common principle that the pari of a part is a part of the voheiU),
the r^resentation of the individual, BucepJudus, comprehends or contains im it
<Ae notion substance.
n. EbGbsssivs Covpbchensive Sobites.
An animal is a substance ;
A quadruped is an animal ;
A horse is a quadruped ;
Bucephalus is a horse ;
Therefore, Bucephalus is m substance.
Or as explicated :
The notion animal comprehends the notion substance ;
The notion quadruped comprehends the notion animal;
The notion horse comprehends the notion quadruped;
The representation, Bucephalus, comprehends the notion horse ;
Therefore (on the common principle, etc.), the repremnUUUm, Bucephalus, cempn-
hends tie notion aubsta$tee.
m. Progressive Extensive Sorites (which is, as cnoanced by the common
copula, identical in expression with the Regressive Comprehensive Sorites,
No. n.):
An animal ts a substance ;
A quadruped is an animal ;
A horse is a quadruped;
Bucephalus is a horse ;
Thertfore, Bucephalus it a tubstaitee.
Or as explicated :
The notion animal is contained tender the ruttion substance;
The notion quadruped is contained under the notion animal ;
The notion horse is contained under the notion quadruped ;
The representation Bucephalus is contained under the notion horse ;
Tkerrfore {on the eemmon principle, etc.), the representation BuoephcduM ts comlaimi
under the notion substance.
foilY. Tbb Reoressivb Exteksitb Soritbs (which is, as expraned by the an-
bigaous copola, verbally identical with the Progressire Comi»«beDsiv»
Sorites, No. I.):
Bucephalus is a horse;
A horse is a <ftadrupeAf
A quadruped is an animal ;
An animal is a substance ;
Therrfore, Bueephalut ie a i
Lkct XIX LOGIC. 263
Or as explicated :
The representation Bucephalus is contained under the notion horat;
The notion horse is contained under tlie notion quadruped ;
The notion quadruped is contained under the notion animal;
The notion animal is contained under the notion substance;
Therefore, the representation Bucephalus is contained under the notion substance.
There is thus not the smallest difficulty either in regard to the
peculiar nature of the Sorites, or in regard to
1. The formal inftr- its relation to the simple syllogism. In the first
ence in Sorites equally , j^. -^ ^y-^^^^^^ tj^^t the formal inference in
necessary as in simple * o •
syllogism. "^^ Sontcs IS equally necessary and equally
manifest as in the simple syllogism, for the prin-
ciple— the part of a part is a part of the whole — is plainly not
less applicable to the remotest than to the most proximate link in
the subordination of whole and part. In the second place, it is
evident that the Sorites can be resolved into as
2. soritea resolvable ^ ^-^ j^ syllogisms as there are middle
Into simple syllof^isms. , i i .
terms between the subject and predicate of the
conclusion, that is, intermediate wholes and parts between the
greatest whole and the smallest part, which the reasoning connects.
Thus, the concrete example of a Sorites, already given, is virtually
composed of three simple syllogisms. It will be enough to show
this in one of the quantities ; and, as the most perspicuous, let us
take that of Comprehension.
The Progressive Sorites in this quantity wae
This iUostnited. as follows (and it is needless, I presume^ to
explicate it) :
Bucephalus is a horse ;
A horse is a quadruped;
A quadruped is an animal;
An animal is a substance ;
Therefore, Bucephalus is a substance.
Here, besides the major and minor terms (Bucephalus and sub-
stance), we have three middle terms — horse,- — quadruped, — ani-
mal. We shall, consequently, have three simple syllogisms. Thus,
in the first place, we obtain from the middle term horse, the follow-
ing syllogism, concluding quadruped of Bucephalus :
I. -^ Bucephalus is a horse;
• But a hoj-se is a quadruped ;
Therefore, Bucephalus is a quadruped.
264 LOGIC. Lect. XIX.
Having thus established that Bucephalus is a quadruped^ we
employ quadruped as a middle term by which to connect Bucephxi-
lu8 with animal. We therefore make the conclusion of the previous
Byllogism (No. I.) the sumption of the following syllogism (No. II.) :
II. — Buctphaltis is a quadruped;
But a quadruped is an animal;
Therefore, Bucephalus is an animal. >
Having obtained another step, we in like manner make a?iimal,
which was the minor term in the precedmg syllogism, the middle
term of the following; and the conclusion of No. II. forms the
major premise of No. III.
III. — Bucephalus is an animal;
But an animal is a substance;
Therefore, Bucephalus is a substattoe.
In this last syllogism, we reach a conclusion identical with that
of the Sorites.
In the third place, it is evident that the Sorites is equally natural
as the simple syllogism ; and, as the relation is
8. Sorites equally equally cogcnt and equally manifest between a
natural as simple syl- i t -• 1111
, j^jj^ whole and a remote, and a whole and a proxi-
mate, part, that it is* far less prolix, and, conse-
quently, far more convenient. What is omitted in a Sorites is only
the idle repetition of the same self-evident principle, and as this can
tvithoat danger or inconvenience be adjourned until the end of a
series of notions in the dependence of mutual subordination, it is
plain that, in reference to such a series, a single Sorites is as much
preferable to a number of simple syllogisms, as a comprehensive
cipher is preferable to the articulate enumeration of the units which
it collectively represents.
Before proceeding to touch on the logical history of this form of
syllogism, and to comment on the doctrine in regard to it main-
tained by all logicians, I shall conclude what it is proper further to
state concerning its general character.
IF LXXI. A Sorites may be either Categorical or Hypothet-
ical ; and, in both forms, it is governed by
Par. LXXI. Sorites. i\^q following laws : — Speaking of the Com-
— Cater or ioal and Hy- _-. . o •. /• ■» • 1
pothetio*!. "^on or Progressive Sorites (in which rea-
soning you will observe the meaning of
tihe word progressive is reversed), which proceeds from the
Lkot. XIX. LOGIC. 265
individual to the general, and to which the other form may be
easily reduced : — 1". The number of the premises is unlimited.
2°. All the premises, with exception of the last, must be affir-
mative, and, with exception of the first, definite. 3°. The first
premise may be either definite or indefinite. 4*. The last may
be either negative or affirmative.
Explication. ^ havc already given you examples of the cat-
Kormuia of Hypo- egorical Soritcs. The following is the formula
theticai Sorites. ^f tj^e hypothetical ;
Progressive.
IfI>is,Cis;
If C it, B is ;
If B IS, A is ;
(In modo ponente),
Now D IS ;
Therefore, A is also.
(Or In modo tollente),
Now A is not ;
Therefore, D is not.
Or, to take a concrete example
Regressive.
If Bis, his;
If C is, Bis;
If D IS, C is ;
(In modo ponente).
Now D is ;
Therefore, A is.
(Or in modo toUcnte),
Now A is not ;
Therefore, D is not.
Progressive.
If Harpagon be ainiricious, he is intent on gam ;
If intent on gain, he is discontented;
If discontented, he is unhappy ;
Noio Harpagon is avaricious ;
He is, therefore, unhappy.
Regressive.
If Harpagon he discontented, he is unhappy;
If intent on gain, he is discontented ;
If avaricious, he is intent on gain ;
Now Harpagon is avaricious ;
Therefore, he is unhappy.
In regard to the resolution of the Hypothetical Sorites into simple
Resolution of Hypo- sy^ogisms, it is evident that in this Progressive
theticai Sorites into Sorites we must take the two first ])ropositions
simple syllogisms. as premises, and then in the conclusion connect
I. Progressive Sorites. ^j^^ antecedent of the former proposition with
the consequent of the latter. Thus:
34
266 LOGIC. Lrct. XIX.
I. — If Harpagon he avaricious, be is inteal on gain.
If intent on gain, he is discontented ,-
Therefore, if Harpagon be avaricious^ he is discontented.
We now establish this conclusion, as the sumption of the
following syllogism :
n. — If Harpagon be avaricious^ he is discontented ; ">
If discontented, he is unhappy ;
Therefore, if Harpagon be avaricious, he is utAappjf.
In like manner we go to the next syllogism :
m. — If Harpagon lye avaricious,, he is unhappy ;
Now Harpagon is avaricious;
Therefore, he is unhappy.
In the Regressive Sorites, we proceed in the same fashion ; only
that, as here the consequent of the second prop-
^ osition is the antecedent of the first, we reverse
the consecution of these premises. Thus :
I. — If Harpagon be intent on gain, he is discontented ;
If discontented, he is unhaj^p ;
Therefore, if Harpagon be intent on gain, he is unhappy.
We then take the third proposition for the sumption of the next,
— the second syllogism, and the conclusion of the preceding for its
subsumption :
11. — ff Harpagon be avaricious, he is intent on gain ;
If intent on gain, he is unhappy;
Therrfore, if Harpagon be avaricious, he is unhappy.
We now take this last conclusion for the sumption of the last
syllogism :
III. — If Harpagon be avaricious, he is unAoppy;
Now Harpagon is avaricioue ,*
Therefore, he is unhappy.
But it may be asked, can there be no Disjunctive Sorites ? To
this it may be answci-ed, that in the sense in
Disjunotlre Sorites. ,. , "' . , ' , • , ,, .
which a categorical and hypotJioticnl syllogism
is possible, — viz., so thut n term of the prec<j|ding iirojiosition
biiuukl bo ihe subject or j)iedicato of the following, — in this sense,
Lect. XIX. LOGIC. 267
a disjunctive sorites is impossible : since two opposing notions,
whether as contraries or contradictoiies, exchide each other, and
cannot, therefore, be combined as subject and predicate. But
when the object has been determined by two opposite characters,
the disjunct members may be amplified at pleasure, and there fol-
lows certainly a correct conclusion, provided that the disjunction
be logicaUy accurate. As :
A. is either B or C.
Now,
"B is either D or E;
D is either H or I;
E is either K or L.
C is either ¥ or G;
F t» either M or N;
G is either O or P.
Thenefore, A is either H, or I, or K, or h, or M, or N, or 0, or P.
Although, therefore, it be true that such a Sorites is correct ;
still, were we astricted to such a mode of reason-
omp ex j^^^ thought would be so difficult, as to be almost
impossible. But we never are obliged to employ
such a reasoning; for when we are once assured that A is either B
or C, — and assured we are of this by one of the fundamental laws of
thought, — we have next to consider whether A is B or C, and if A is
B, then all that can be said of C, and if A is C, then all that can be
said of B, is dismissed as wholly irrelevant. In like manner, in the
case of B, it must be determined whether it is D or E, and in the
case of C, whether it is F or G ; and this being determined, one of
the two members is necessarily thrown out of account. And this
compendious method we follow in the process of thought spon-
taneously, and as if by a natural impulsion.
So much for the logical character of the Sorites. It now remains to
make some observations, partly historical, partly critical, in connec-
tion with this subject.
In regard to the history of the logical doctrine of this form of
reasoning, it seems taken for granted, in all the
Historical notice of systems of the Science, that both the name Sorites^
the logical doctrine of t j . i • ^^ • j .1 i •
as apphed to a cham-syllogism, and the analysis
of the nature of that syllogism, are part and par-
cel of the logical inheritance bequeathed to us by Aristotle. Noth-
ing can, however, be more erroneous. The name
Neither name nor Sorites docs not occur in any logical treatise of
jgjQtjg Aristotle ; nor, as far as I have been able to dis-
cover, is there, except in one vague and cursory
allusion, any reference to what the name is now employed to ex'
268 LOGIC. Lect. XIX
press. ^ Nay, further, the word Sorites is never, I make bold to say,
applied by any ancient writer to designate a certain form of reason-
ing. On the contrary, Sorites, though a word in
Sorites, with ancient not unfrequent employment by ancient author .<,
authors, used to des- „o\vhere occuiTS in any other logical meanino
i/jnate a particular i j?
kit.d of sophism t"^" ^^^^ of a particular kind of sophism, of
which the Stoic Chrysippus \vas reputed the in-
ventor.'^ 2<i»pos, you know, in Greek, means a heap or pile of any
aggregated substances, as sand, wheat, etc. ; and Sorites^ literally a
heaper^ was a name given to a certain captious argument, which
obtained in Latin fi'om Cicero the denomination of acervalis.^ The
nature of the argument was this: You were asked.
The nature o this ^^^ example, whether a certain quantity of some-
sophism. ^ '■ \ ^ -* •/
thing of variable amount were large or small, —
say a certain sum of money. If you said it was small, the adversary
went on gi-adually adding to it, asking you at each increment
whether it were still small ; till at length you said that it was lai'ge.
The last sum which yon had asserted to be small, was now compared
Vith that which you now asserted to be large, and you were at
length forced to acknowledge that one sum which you maintained
to be large, and another which you maintained to be small, differed
from each other by the very pettiest coin, — or, if the subject were
a pile of wheat, by a single com. This sophism, as applied by Eubu-
iides (who is even stated by Laertius* to be the inventor of the
Sorites in general), took the name of <^aAaxpo9, calvus, the bald. It
was asked, — was a man bald who had so many thousand haira ; you
answer. No : the antagonist goes on diminishing and diminishing
the number, till cither you admit that he who was not bald with a
certain number of hairs, becomes bald when that complement is
diminished by a single hair ; or you go on denying him to be bald,
until his head be hypothetically denuded. Such was the quibble
which obtained the name of Sorites, — acervalis, climax, gradatio,
etc. This, it is evident, had no real analogy with the form of rea-
soning now known in logic under the name of Sorites'.
" Inrenta*. Chrytippe, tul finltor •eerri." — Ed.
1 The passage referred to is probably AhoI. > Persius, Sat. vi. 80.
Prior., i. 25. But there was no need of a
special treatment of the Sorites, as it is
merely a combination of ordinary sy^- [Cicero applies SoritM to an argument which
Ipjfisms, and subject to the game rules. — Ed. we would call a Sorius, but it oould also be a
[The principle of the Sorites is to be found in Chr)-8ippean. Dt Finibus, h. iv. c. 18.]
Aristotle's rule, Catrg., c. 2. " Prcdicatum S D« Divinatione, ii. 4. " Quemadmodum
prxdicati est prsdicatum subjecti." 8ee also, Soriti resistas? quern, si necesse sit, Latino
Anal. Post., I. 23 tt trg. Cf. Tticius, Comment., verbo llceat af*rraif»n appellare " Cf. Facoio<
p. 169. Bertius, Loglea Prripatrtiea, L Hi latl, Acroasis, ii. p. 17 et st^. — Ed.
Appendix, p. 179.] 4 L. ii. f 108. — Ed
Lect.XIX. logic. !i69
But when was the name perverted to this, its secondary significa-
tion ? Of this I am confident, that the change was
Lanrentius Valla the ^ot older than the fifteenth century. It occurs in
first to use Sorites in ^^^^ ^^ ^^^ logicians previoUS tO that period,
its present accepta- '^ '■ * . ,
tjQQ_ It is to be found in none of the Greek logicians
of the Lower Empire ; nor is it to be met with
in any of the more celebrated treatises on Logic by the previous
Latin schoolmen. The earliest author to whose writings I have been
able to trace it, is the celebrated Laurentius Valla, whose work on
Dialectic was published after the middle of the fifteenth century.
He calls the chain-syllogism — "coacervatio syllogismorum (quem
Graeci <rwpbv vocant").^ I may notice that in the Dialectica of his
contemporary and rival, George of Trebisond, the process itself is
described, but, what is remarkable, no appropriate name is given to
it.' In the systems of Logic after the commencement of the six-
teenth century, not only is the form of reasoning itself described,
but described under the name it now bears.
I have been thus particular in regard to the history of the Sorites,
— word and thing, — not certainly on account
The doctrine ofio- ^^ ^^^ importance of this history, considered in
gicians regarding the . ,/. , ,
Sorites illustrates their itself, but because it Will enable you the better
one-sided view of the to ajiprehcnd what is now to be said of the illus-
nature of reasoning in tration which the doctrine, taught by logicians
^*°^™ ■ themselves of the nature of this particular pro-
cess, afibrds of the one-sided view which they have all taken of the
nature of reasoning in general.
I have already shown, in regard to the simple syllogism, that all
deductive reasoning is from whole to part ; that there are two kinds
of logical whole and two kinds of logical part, — the one in the
quantity of comprehension, the other in the quantity of extension ; —
and that there are consequently two kinds of reasoning corresponding
to these several quantities. I further showed that logicians had in
simple syllogisms marvellously overlooked one, and that the simplest
and most natural, of these descriptions of reasoning, — the reason-
ing in the quantity of comprehension ; and that all their rules were
exclusively relative to the reasoning which proceeds in the quantity
of extension. Now, in to-day's Lecture, I have shown that, as in
simple syllogisms, so in the complex form of the Sorites, there is
equally competent a reasoning in comprehension and in extension,
— though undoubtedly, in the one case as in the other, the reason-
1 DiaUctuee DisptOationes, Lib. iii. C. 12. See 2 See Gtorgii Trap'zuntii De Re Dialectica
Laurentii YalU Opera, Basilese, 1540, p. 742.— LibeUus, Coloniae, 1533, f. 60». Cf. the Scholia
Ed. of Neomagus, ibid. f. 67'>. — Ed.
270 LOGIC. Lect. XIX
ing in comprehension is more natural and easy in its evolution than
the reasoning in extension, inasmuch as the middle term, in the
former, is really intermediate in position, standing between th« ma-
jor and the minor terms, whereas, in the latter, the middle term is
not in situation middle, but occupies the position of one or other of
the extremes.
Now, if in the case of simple syllogisms, it be man^ellous that
logicians should have altogether overlooked the
Logicians have over- possibility of a reasoning in comprehension, it is
looked the Sorites of , , , ,, ^i ^ -.j »i • .1 •
_ ^^^ doubly marvellous that, with this their prepos-
session, they should, in Ihe case of the Sorites,
have altogether overlooked the possibility of a reasoning in exten-
sion. But so it is. * They have all followed each other in defining
the Sorites as a concatenated syllogism in which the predicate of
the proposition preceding is ra^ade the subject of the proposition fol-
lowing, until we arrive at the concluding proposition, in which the
predicate of the last of the premises is enounced of the subject of
the first. This definition applies only to the Progressive Sorites in
comprehension, and to the Regressive Sorites in extension : but
that they did not contemplate the latter form at all is certain, both
because it is not lightly to be presumed that tliey had in view that
artificial and recondite forra^ and because the cxaniples and illustra-
tions they supply positively prove that they had not.
To the Progressive Sorites in extension, and to the Regressive
Sorites in comprehension, tJiis definition is iaap-
Difference between pUcable ; for in these, the subject of the premise
the two forms of Sori- -,• • .1 t /», •,.,
,j^ precedmg is not the predicate ol the premise fol-
lowing. But the diflerence between tlie two
forms is better stated thus: — In the Progressive Sorites of com-
prehensioiTand the Regressive Sorites of extension, the middle terms
are the predicates of the prior premises, and the subjects of the pos-
terior; the middle term is here in position intermediate between
the extremes. On the contrary, in the Progressive Sorites of exten-
.sion and in the Regressive Sorites of comprehension, the middle
terms are the subjects of the prior premises and the predicates of
the posterior ; the middle term is here in position not intermediate
between the extremes.
To the question, — why, in the case of simple syllogisms, the
logicians overlooked the reasoning in comprehension, and, in the
1 (Ridiger notices tlic error of those wlio rcripntelici. ef ciitn his (Jassendus, qui Sori-
mnke Sorites only of compieltcntiive wliole. »itn mlinii ad pricdicKtum iK-rtinere exisU-
•tjee hie Dr .Scmm( Veri tt Falsi,, i, ii. c. 10, 4 6_ niat^°— J£i>.]
p. 400. Ci. p. MS u,i iR.] il-'4"jnaw»< vuXgu
I
Lkct. XIX. LOGIC. 2X1
case of the Sorites, the reasoning in extension, it is, perhaps, im-
possible to afford a satisfactory explanation,
ro a e reason g^^ ^_^ ^ plausibly coniecture, what it is out
why logicians over- •' ^ •> •' '
looked, in the case of of our power Certainly to prove. In regard to
simple syllogisms, the simple syllogisms, it was an original dogma of the
reasoning iu Compre- pjat^nic school, and an early dogma of the Peii-
liension. . , . . ,
patetic, that philosophy — that science, strictly
so called — was only conversant with, and was exclusively con-
tained in, universals; and the doctrine of Aristotle, which taught
tliat all our general knowledge is only an induction from an observa-
tion of particulars, was too easily forgotten or perverted by his follow-
ers. It thus obtained almost the force of an acknowledged principle,
that everything to be known must be known under some general
form or notion. Hence the exaggerated importance attributed to
definition and deduction ; it not being considered, that we only take
out of a general notion what we had previously placed therein ;
and that the amplification of our knowledge is not to be sought for
from above, but from below, — not from speculation about abstract
generalities, biit from the observation of concrete particulars. But,
however erroneous and ii'rational, the persuasion had its day and
influence ; and it perhaps determined, as one of its effects, the total
neglect of one-half, an<i that not the least important half, of the
reasoning process. For, while men thought only of looking up-
wards to the more extensive notions, as the only objects and the
only media of science, they took little heed of the more compre-
hensive notions, and absolutely contemned individuals, as objects
which could neither be scientifically known in themselves, nor sup-
ply the conditions of scientifically knowing aught besides. The
logic of comprehension and of induction was, therefore, neglected
or ignored, — the logic of extension and deduction exclusively cul-
tivated, as alone affording the niles by which we might evolve
higher notions into their subordinate concepts. This may help to
explain why, subsequently to Aristotle, Logic was cultivated in so
partial a manner; but why, subsequently to Bacon, the logic of com-
prehension should still have escaped observation and study, I am
altogether at a loss to imagine. But to the question, — why, when
reasoning in general was viewed only as in the quantity of exten-
sion, the minor form of the Sorites should have
/. '!. ^' I" x ^ "been viewed as exclusively in that of compre-
case of the Sorites, •' i r i
they ovcriooiced the hensiou, may, perhaps, be explained by the fol-
leasoning in Exten- lovvinjT consideratioTi : this form was not origi-
»ion
nally analyzed and expounded by the acuteness
of Aristotle. But it could not escape notice that there was a form
272 LOGIC. Lect. XIX
of reasoning, of very frequent employment, botli by philosophers
and rhetoricians, in which a single conclusion was drawn from a
multiplicity of premises, and in which the predicate of the forego-
ing premise was usually the subject of the following. Cicero, for
example, and Seneca, are full of such arguments ; and the natural
and easy evolution of the reasoning is indeed peculiarly appropriate
to demonstration. Thus, to prove that every body is movable, we
have the following self-evident deduction. Every body is in space ;
what is in space is in some one part of space ; what is in one part
of space may be in another; what may be in another part of space
may change its space; what may change its space is movable;
therefore, every body is movable. When, therefore, Valla, or who-
ever else has the honor of first introducing the consideration of this
form of reasoning into Logic, was struck with the cogency ftnd
clearness of this compendious argumentation, he did not attempt to
reduce it to the conditions of the extensive syllogism ; and subse-
quent logicians, when the form was onCe introduced and recognized
in their science, were, as usual, content to copy one from another,
without subjecting their borrowed materials to any oiiginal or
rigorous criticism.
Ut nemo in seso tentat descendere; — nemo !
Sed prsecedenti spectatur mantica tergo.^
Accordingly, not one of them has noticed, that the Sorites of their
systems proceeds in a different quantity from that of their syllo-
gisms in general, — that their logic is thus at variance with itself;
far less did any of them observe that this, and all other forms of
reasoning, are capable of being drawn in another quantity fi'om
that which they all exclusively contemplated. And yet, had they
applied their observation without prepossession to the matter, they
would easily have seen that the Sorites could be cast in the quan-
tity of extension, equally as common syllogisms, and that common
syllogisms could be cast in the quantity of comprehension, equally
as the Sorites. I have already shown that the same Sorites may be
drawn either in comprehension or in extension ; and in both quan-
tities proceed either by progression or by regres-
Exampie of the So- gion. But the example given may, perhaps, be
rites in Comprehen- . . i -i t i /» ^ i
.ion and Extension. Viewed as Selected. Let us, therefore, take any
other; and the first that occni-s to my recollec-
tion is the following from Seneca,' which I shall translate :
1 renins, ir. 23. - Ed. t ^ritt., 8S. — Ed.
Lect. XTX. tOGta. 273
Be toho is prudent is temperate ;
He who is temperate is constant ;
He who is constant is iivpcrturbed ;
He who is unperturbed is without sorrow ;
He who is without sorrow is happy ;
Therefore, the prudent man is happ;/.
In tliis Sorites, everything slirles easily and smoothly frojn the
whole to the ]iarts of comprehension. But, tliough the process will
be rattier more by hitches, the descent under extension will, if not
quite so pleasant, be equally rapid and certain.
Be who is vnthout sorrow is happy;
He who is unperturbed is unthout sorrow;
Be who is constant is unperturbed;
Be who is temperate is constant :
Be xvho is prudent is temperate;
Therefore, the prudent man is happy.
I do not think it necessary to explicate these two reasonings,
which you are fully competent, I am sure, to do without difficulty
for yourselves.
What renders it still more wonderful that the logicians did not
evolve the competency of this process in either
e oc euian o- quantity, and thus obtain a key to the opening
up of the whole mystery of syllogistic reason-
mg, is this : — that it is now above two centuries since the Inverse
or Regressive Sorites in comprehension was discovered and signal-
ized by Rodolphus Goclenius, a celebrated philosopher of Marburg,
in which university he occupied the chair of Logic and Meta-
physics.^ This Sorites has from him obtained the name of Gocle-
nian; while the progressive Sorites has been called the common or
Aristotelian. This latter denomination is, as I have previously
noticed, an error; for Aristotle, though certainly not ignorant of
the process of reasoning now called /Sorites, does not enter upon its •
consideration, either under one form or another. This observation
by Goclenius, of which none of our British logicians seem aware,,
was' a step towards the explication of the whole process; and we
are, therefore, left still more to marvel how this explication, so easy
and manifest, should not have been made. Before terminating this
subject, I may mention that this form of syllogism has been some-
times styled by logicians not only /Sorites, but also coacervatio, con-
1 Goclenii Isagoge in Orgarium ArL'itotcli's, clenian Sorites before Goclenius, see Pacius,
Francof., 1698, p. 265 —Ed. [For the Go- Comment, in Anal. Prior., 1. 25. p. 159]
35
,274
LOGIC.
Lkct. XIX
Epicheirema and So-
rites, as polysyllo-
gisms, comparatively
simple, and not pleon-
«8tJC.
fferies, ffradatio, climax, and deprimo adtdtimum. The old name,
before Valla, which the process obtained among the Greek logicians
of the Lower Empire, was the vague and general appellation of
complex syllogism., — cruXXoyw/jios (ruv^crds.^
So much for the two forms of reasoning which may be regarded
as composite or complex,- and which logicians
have generally considered as redundant. But
here it is proper to remark, that if in one point,
that is, as individual syllogisms, the Epicheirema
and Sorites may be viewed as comparatively
complex, in another, that is, as polysyllogisms, they may be viewed
as comparatively simple. For, resolve a Sorites into the various
syllogisms afforded by its middle terms, and compare the multitude
of propositions through which the conclusion is thus tedidusly
evolved, with the short and rapid process of the chain-syllogism
itself, and, instead of complexity, we should rather be disposed to
predicate of it extreme simplicity.' In point of fact, we might
arrange the Epicheirema and Sorites with far greater propriety
under elliptical syllogisms, than, as is commonly done by logicians,
under the pleonastic. This last classification is, indeed, altogether
erroneous, for it is a great mistake to suppose that in either of these
fonns there is aught redundant.
1 [Blemmidas, Epitomt Logiea, o. 81.]
* [See Leibnitz, Nouveaux Essais, L. ir.
xtU. i 4, pp. 445, 446, 448, ed. Baspe.]
LECTURE XX.
STOICHEIOLOOY.
SECTION II.— OF THE PRODUCTS OF THOUGHT
III —DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO EXTERNAL
FORM.
B. DEFECTIVE, — ENTHYMEME.
C. REGULAR AND IRREGULAR, — FIGURE AND MOOD.
I PEOCEED now to the Second Class of Syllogisms, — those, to
wit, whose External Form is defective. This
tive'i!Srte™"iFr^' <'^««s I give ill Conformity to the doctrine of
modern logicians, whose unanimous opinion on
the subject I shall comprehend in the following paragraph.
% LXXTI. According to logicians, in general, a defective
syllogism is a reasoning in which one only
Par. Lxxn. Tue ^^ ^^^ premises is actually enounced. It
Enthymeme. i^ •'
is, therefore, they say, called an Enthymeme
{cvSvfx.Tjfia), because there is, as it were, something held back in
the mind (cV ^vfiwi). But, as it is possible to retain either the
sumption or the subsuraption, the Enthymeme is thus of two
kinds : — an Enthymeme of the First, and an Enthymeme of
the Second, Order. The whole distinction is, however, errone-
ous in principle, and, even if not erroneous, it is incomplete ;
for a Third Order of Enthyraemes is competent by the suppres-
sion of the conclusion.
Such, as it is stated in the former part of the paragi'aph, is the
doctrine yon will find maintained, with singular unanimity, by
modern logicians ; and, with hardly an exception, this classification
276 LOGIC. Lect. XX.
of syllogisms is stated noi only without a suspicion of its own cor-
rectness, but as a division established on the
Explication. The .
common doctrine of authority of the great father of logic himself,
the Enthymeme futile, In both assertions they are, however, wrong,
and erroneously at- foj. ^^q classification itsclf is futile, and Aristotle
tributed to Aristotle. re :i '^ i •• ■■ '
anords it no countenance ; winle, at the same
time, if a distinction of syllogisms is to be taken from the ellipsis
of tlieir propositions, the subdivision of enthymemcs is not com-
plete, inasmuch as a syllogism may e.xist with both premises ex-
pressed, and the conclusion understood.
I shall, therefore, in the first place, show that the Enth}Tneme, as
at syllogism of a defective enouncement, constitutes no special form
of reasoning; in the second, that Aristotle does not consider a syl-
logism of such a character as such a special form ; and, in the third,
that, admitting the validity of the distinction, the restriction of the
Enthymeme to a syllogism of one suppressed premise cannot be
competently maintained.
' I. In regard, then, to the validity of the distinction. This is
disproved on the following grounds: First of
I T!;t. Ertfiniht^me j,|]^ ^■^^ discrimination of the Enthymeme, as a
i.ut u Fpecial lot m of n • n i . ,.
reasoning. Syllogism of One suppressed premise, from the
ordinary syllogism, would involve a discrinii-
hation of the reasoning of Logic from the reasoning in common
use; for, in general reasoning, we rai*ely express ail the proposi-
tions of a syllogism, and it is almost only in the treatises on Ab-
stract Logic that we find examples of reasoning in which all the
members are explicitly enounced. But Logic does not create new
f6fms of syllogism, it merely expounds those which are already
gi^en ; and while it shows that in all reasoning there are, in the
mental process, necessarily three judgments, the mere non-expres-
sion of any of these in language, no more constitutes in Logic a
particular kind of syllogism, than docs the ellipsis of a term consti-
tute in Grammar a particular kind of concord or government. But,
secondly, Syllogism and Enthymeme are not distingnished as re-
spectively an intralogical and an extralogical form ; both are sup-
posed equally logicah Those who defend the distinction are, there-
fore, necessarily compelled to maintain, that Logic regards the
R:<S(jident of the external expfession, and not th« essence of the
internal thought, in holding that the Enthymeme is really a defec-
tive reasoning.^
1 Cotnpore Discussions, p. 153 r« srq. — Ed. Derodon, Logiea ReatittHa, Pars V. tract, i. a
2 [Thct Syllogism and Enthymeme are not 1., p. 608.]
properly distinct species of reasoning, see
I^,CT. XX. LOGIC 27t
It thus appears!, tii8t to eonstttate ihe E«thymerae as a speeios
of reasoning distinct from Syllogisms Proper, by the difference of
perfect and iinpei'fect, is of all absurdities the greatest. But is this
absurdity the work of Aristotle ? — and this le^s us to the second
bead.
II. Without entering upon a regular examination of the various
passages of the Aristotelic treatises relative to
II. The distinction tjjjg point, I may observe, in the first place, that
of the Euthyrueme as a • ... ^i ' i j i • 1^1^
a special form of rea- AiistoUe expressly declares m general, that a
Boning not made by syllogism is Considered by the logician, not in re-
Aristotie. latiou to jts expression (ou tt/sos tov l^oi Aoyov), but
exclusively as a mental process (dAA.a tt/ws tov €v
rg i/o^xS ^o'yov).^ The distinction, therefore, of a class of syllogisms,
as founded on a verbal accident, he thus of course, implicitly and by
anticipation, condemns. But Aristotle, in the
Aristode —what sccoud place, docs distinguish the Enthymeme
as a certain kind of syllogism, — as a syllogism
of a peculiar matter, — as a syllogism fi-om signs and likelihoods.*
Xow if, having done this, it were held that Aristotle over and above
distinguished the Enthymeme also as a syllogism with one sup-
pressed premise, Aristotle must be 8<jp^posed to define the Enthy-
meme by two differences, and by two differences which have no
mutual analogy ; for a syllogism from signs and likelihoods does not
more naturally fall into an elliptical form than a syllogism of any
other mattei'. Yet this absurdity has been and is almost universally
believed of the acutest of human intellects, and on grounds which,
when examined, afford not the sliglitest warrant for such a conclu-
sion. On the criticism of these grounds it would be out of place
here to enter. Suffice it to say, that the texts in the Organon and
Rhetoric, which may be adduc^ed in support of the vulgar opinion,
will bear no such interpretation ; — that in one passage, where the
word arcX^s {imperfect) is applied to the Enthymeme, — this word,
if genuine, need signify only that the reasoning from signs and
probabilities affords not a perfect or necessary inference ; but that,
in point of fact, the woi'd arcX^s is there a manifest interpolation,
made to accommodate the Aristotelic to the common doctrine of the
Enthymeme, for it is not extant in the oldest manuscripts, and has,
accordingly, without any reference to the present question, been
ejected from the best recensions, and, among others, from the recent
o<Ution of the works of Aristotle by the Academicians of Berlin, —
■^n edition founded on a collation of the principal manuscripts
1 Ancd. Post., i. 10. — Ed. 2 Anal. Prior., ii. 27. RAet., i. 2. — Ed.
278
LOGIC.
Lect. XX
Applications of the
term Enthymeme.
By Dionysius of
Ualicarnassus. Au-
thor of Rhetoric to Alex-
ander. Sopater. Aulus
Uellius. Cicero. Quin-
tilian.
tbrougliout Europe.' It is not, however, to be denied that the term
Enthymeme was applied to a syllogism of some
unexpressed part, in very ancient times; but,
along with this meaning, it was also employed by
the Greek and Roman rhetoricians for a thought
in general, as by Dionysius the Halicarnassian,^
and the author of the Rhetoric to Alexander^ at-
tributed to Aristotle,^ — for an acute dictum, as
by Sopater * and Aulus Gellius,* — for a reasoning
from contraries or contradictories, as by Cicero.^ Quintilian gives
tbree meanings of the term ; in one sense, signifying " omnia mente
concepta^'' in another, '■'- sententia cum, rationed"* in a third, '■'•argu-
menti conclusio, r)cl ex consequentihns, vel ex repngnantihus?''^
Among the ancients, who employed the term for a syllogism with
some suppressed part, a considerable number
held, with our modern logicians, that it was a
syllogism deficient of one or other premise, as
Alexander the Aphrodisian, Ammonius Hermia>,
Philoponus,* etc. Some, however, as Pachy-
meres," only recognized the absence of the
major premise. Some, on the contrary, thought,
like Quintilian,"^ that the suppressed proposition
ought to be the conclusion ; — nay, Ulpian, the Greek commentator
Denoted, with some
of the ancients, a
syllogism with some
suppressed part. The
Aphrodisian. Am-
monius. Fhiloponus.
Pachymeres. Quintil-
ian. Ulpian. Scholi-
ast on Hermogenes.
1 For a fuller history of this interpolation,
see Discussions, p. 164. — Ed. [For the correct
doctrine of the Aristotelic Enthymeme, see
Mariotte, Essay de Logiquc, P. ii. dljc. iii. p.
168, Paris, 1678. — Ed. ]
8 Epistola ad Cn. Pomptium de. pracipuis His-
toricis, c. 5. Tfjj ftiuToi KoXXiXoyias (Kfiyov
Koi 70V irKovrov rwv ivbvixfftArwy Kwrh
•KoKv vffTfpfi, The expression irKovroi iv-
dvfxendTup is rendered by J. C. T. Ernesti,
Gedankin FiUle ; see his Lexikon Ttchnologicr
Graeorum Rhetoriea, v. ivbvufixa. Tlie same
sentence is repeated in nearly the same words
by Dionysius, in his Veterum Scriptorum Cen-
sura, iii. 2. — Ed.
* 3 The author of the Rhetorica ad AUxan-
drum, c. 8, classes the enthymeme among
proofs (iriffTtis), and in c. 11, defines it as a
proof, drawn from any kind of opposition.
'''E.vbvft.iift.aTa 8' iariv oh ix6vov rh. ry \'by(f
KoX rij -irpd^fi ivavriovfifva, oAXA »ca) ro7s
iKKoii &.ira<Tiv. This work Is attributed by
Victorias to Anaximenes of Lampsacus, and
this conjecture is adopted by the latest editor,
Spengcl. — Ed.
< Sopatri Apameensis Prolegomena (n Aristi-
dem. Aristidis Op. Omit., ed. Jebb, vol. L f. d.
S. Kal TTJ rHy iv^vfitiixdroiy ruKvirriTi 8»j-
fioffdfyl^fi. In Canter's Prolegomena this ex-
pression is rendered sentenliarum densitas, and
the word iydufirifjMTiK6s in the same passage
by argutus in argumentis. But compare Dis-
cussions, p. 157. — Ed.
i Tfoctes Attira, vi. 13. " Qnserebantur
autem non gravia ncc rcvercnda, sed ^I'^u-
fx-finara quxdam lepida et miunta." — Ed.
« Topiea, c. 13. — Ed.
T Jn.U. Orat., v. 10, 1. — Ed.
8 See Alexander, In Topiea, pp. 6, 7, ed.
Aid. 1513. Ammonius, In Quinque Toees Por-
phyrii^ {. 5 a, ed. Aid. 1546. Philoponus, In
Anal. Post., {. 4 a, ed. Aid. 1534. These author-
ities are cited in the author's note, Discussions,
p. 156. —Ed.
0 Epitome I^gices Aristotelis, Oxon.,\G&3, p.
113. See also his Epito}ne in Universam Aristo-
telis Disierendi Artem, appended to Rasarius's
translation of Ammonius on Forpbyrj
Lugd., 1647, p. 244. — Ed.
lOiJut. Orat., V. 14, 1. —Ed.
LrcT. XX. LOGIC. 279
of Demosthenes, and the scholiast on Hei-mogenes the Rhetorician,^
absolutely define an Enthymerae — "a syllogism, in which the con-
clusion is unexpressed."^
III. This leads us to the third head ; for on no principle can it be
shown, that our modern logicians are correct in
III. Admitting the denying or not contemplating the possibility of
validity of the discrim- ,*'r ^ , ^,. —ii i'-
iuation of the Enthy- the reticcuce of the conclusion. The only prin-
meme, it cannot be ciplc On which a sylloglsm is Competent, with
restricted to a syiio- q^q qj. ot^er of its propositions unexpressed, is
sismofoneBuppressed .. ^i^^i ^ t-x -r- ^
this, — that the part suppressed is too manliest
premise. ' r rjr
to require enouncement. On this principle, a
syllogism is not less possible with the conclusion, than with either
of the premises, understood; and, in point of fact, occurs quite as
frequently as any other. The logicians, therefore, to complete their
doctrine, ought to have subdivided the Enthy-
Exampiea of Enthy- meme not -merely into Enthymemes of the first
memes of the. First, ^^^ second, but also into Enthymemes of the
Second, and Third, , • , t t i . , -,
Qy^gj. third order, according as the sumption, the sub-
sumption, or the conclusion is suppressed.' Aa
examples of these various Enthymemes, the following may suffice:
The Explicit Syllogism.
Every liar is a covoard ;
Caius is a liar ;
Therefore, Caius is a coward.
I. Enthtmemb of the First Ordee — (the Sumption understood.)
Caius is a liar ;
Therefore, Caius is a couxtrd.
n. £nththehe of the Second Order — (the Subsumption understood.)
Every liar is a coward ;
Therefore, Cains is a coward.
ni. Enthtmeme of the Third Order — (the Conclusion understood.)
Every liar is a coward ;
And Caius is a liar.
1 Ulpian, Ad Demosth. Olynth., ii. f. 7 b, ed. ities on this question is given by the author,
Aid., 1527. Anonymi ad Hermogenem, De Discussions, p. Ibl . — Ed.
Inventione, lib. iv. See RhHores Grceci, ed. 3 [That the Enthymeme is of three orders is
Aid. 1509, vol. ii. p. 371. In the same work, held by Victorinus (in Cassiodorus Opera, vol.
p. 365, the scholiast allows that either premise- ii. p. 536, ed. 1729. Rhetores Pithgei, p. 3il, ed.
or conclusion may be omitted. — Ed. 1599), or rather of four orders, for tliere may
be an Enthymeme with only one propositiOB
2 An enlarged and corrected list of author- enounced. See Victorinus, as above.]
LOGIC.
Lect. XX.
Epigrammatic ex-
amples of Euthymeme
witli suppressed con-
elusiou.
In this last, you see, the suppression of the concduaion is i>ot only
not yioUnit, bat its expression is even more su-
pei-fluous than that of either of the premises.
There occure to rae a olever epigram of tlie
Greek Anthology, in ^yhich there is a syllogism
with the conclusion supf^ressed. I shall not
quote the original, but give you a Latin and English imitation, which
will serve equally well to illustrate the point in question.^ The
Ijatin imitation is by the learned printer Henricus Stephanus, and
he applies his epigram to a certain Petrns, who, I make no doubt,
was the Franciscan, Petrus a Ccwnibus, whom Buchanan, J5eza,
Rabelais, and others have also satiiized." It rcHis, tk» I recollect,
thus:
"Sunt mooachi oeqaam; nequara uon unas ec ultcrc
Pr«cer PeUiim omnes : est 8cd et hie tooaachus."
The English imitaUon was written by Porson upon Gottfried
Hermann (when this was written, confessedly the prince of Greek
scholars), who when hardly twenty had attacked Poi-son's famous
canons, in his work, J)e Metris Grcecoriim et JiotnaHortWi. Tiw
merit of the epigram does not certainly lie in its truth.
"The Germans in Greek,
Are sadiy to seek ;
Not five in five score,
Bot ninety -five more; ^
All, save only Hermann,
And Hermann 's a German."
In these epigrams, the conclusion of the syllogism is suppressed,
yet its illative force is felt even in spite of the express exception ;
nay, in really conquering by implication the apparent disclaimer,
consists the whole point and elegance of the epigram. To put the
former into a syllogistic shape, —
1 The original is an epigram of rhocyIi4.e!>,
preserved by Strabo, B. x. p. 487, ed. Casau-
bon, 1620. Compare Anthologia Grata, 1. p.
64, ed. Bruiick. Lips , 1794. Porta Minores
Groan, ed. Gaiefoj;d,i. p. 444.
Koi rdSt (f)aiKv\lSeu ' A^piot koxoI ' o'jx
6 ifXv, hs S' o& •
Tlivjti, jr\i)v npoKKiovi ' koI Ilf»OK\tT}s
/^ptoi.
For t^c Latin imitation by Stepliamis, «ea
THeod. Bextt Potmaia, ittm ex Gmrgw Ruchmt-
CM«, alii*qtu variis insignibus pottis excerpta tor-
mina. Excudebat H. Stephanus, ex tujut etiatn
Epigramtnalis Gratis et Latinis aliquot eaieris
adjecta sunt, 1569, p. 217.
The parody by Porsoo is f^reta is 4 /^^f*
AecouMt qfth* Uut Mr Riclu/trd f'orspn, M. 4.,
p. 14. Loudou, 1S08. The oifgiiial Grade.
with Porsou'e imitation, is al^ugivc^ in Dr.
Wfillesley's Aatkologia Polygloita, p. 438 — KP.
- Sec BuoiMitan, Fmneiseaays. 1. i(H fioi^
Poemata, p. 86, ed. 1569. Rabelais, L. iii. dk
li.-fil^
Lect. XX. LOGIC. 281
Sumption — The monks, one and all, are good-for-nothing varlets, excepting POer;
Subsumption — But Peter is amonk.
Now, what is, what must be, ufldergtood to complete tiie sense ?
— Why, the conclusion,^
Therefore, Peter is a yoodfor-nothing varlet like the rest.
There is recorded, likewise, a dying deliverance of the philosopher
Hegel, the wit of whicli depends upon the same ambiguous reason-
ing. " Of all my disciples," he said, " one only understands my
philosophy; and he does not."^ But we may take this for an ad-
mission by the philosopher himself, that the doctrine of the Absolute
transcends human comprehension.
What has now been said, may suffice to show, not only that we
may have enthymemes with any of the three propositions under-
stood, but that the distinction itself of the enthymeme, as a species
of syllogism, is inept.
I now go on to the. Third Division of Syllogisms, under the head
of their External or Accidental form, — I mean
. > ogMins, e- ^^^ division of syllogisms into Regular and
gular and Irregular. .' o o
Irregular, — a distinction determined by the or-
dinary or extraordinary arrangement of their constituent parts. I
commence this subject with the following paragraph.
*|[ LXXIII. A syllogism is Irregular by relation, — 1°. To
the transposed order of its Propositions; 2°.
Par. LXXIII. Kinds „ , , r- • rr.
of Irregular syiio- To the transposcd Order of its lerms; and
eisnis- 3°. To the transposed order of both its
Propositions and Terms. Of these in their order.
1". A syllogism in extension is Regular, in the order of its
Propositions, when the subsumption follows the sumption, and
the conclusion follows the subsumption. In this respect (dis-
counting the difference of the quantities of depth and breadth),
it, therefore, admits of a fivefold irregularity under three heads,
— for either, 1°. The two premises may be transposed; m\ 2°.
The conclusion may precede the premises, and here, either the
sumption or the subsumption may stand first; or, 3"*. The con-
clusion may be placed between the premises, and here either
the sumption or the subsumption may stand first. Thus, repre-
senting the sumption, subsumption, ^ud conclusion by the letters
A, B, C, we have, besides the regular order, 1°. B, A, C, — 2°. C,
J See Discussions, p. 788. — Ed.
36
•282
LOGIC.
Lkct. XX.
A, B,— 3°. C, B, A,— 4°. A, C, B,— 5». B, C, A. (This doctaine
of the logicians is, however, one-sided and (erroneous.)
2°. A syllogism is Regular or Irregular, in respect to the or-
der of its Terms, according to the place which the middle term
holds in the premises. It is regular, in Comprehensive Quan-
tity, when the middle term is the predicate of the sumption and
the subject of the subsumption; — in Extensive Quantity, when
the middle term is the subject of the sumption and the predi-
cate of the subsumption. From the regular order of the terms
there are three possible deviations, in either quantity. For the
middle term may occur, 1°. Twice as predicate ; 2°. Twice as
^abject ; and, 3°. In Comprehensive Quantity, it may in the
sumption be subject, and in the subsumption predicate'; in Ex-
tensive Quantity, it may in the sumption be predicate, and in
the subsumption subject. Taking th«j letter M to designate tho
middle term, and the letters S and P to designate the subject
and predicate of the conclusion, the following scheme will rep-
resent all the possible positions of the middle term, both in its
regular and its irregular arrangement. The Regular constitutes
tho First Figure ; the Irregular order the other Three.*
A. — In Comprehension.
I.
II.
III.
IV.
S is M.
S is M.
M is S.
M isS.
M IS P.
P tsM.
M is P.
Pis M.
S is P.
S IS P.
S is P.
S isP.
B. — ly Extension.
I.
II.
III.
rr.
M IS P.
P isM.
M is P.
P«M.
S isM.
S if M
M is S.
M is S.
S w P.
S t» P
S is P.
S is P.
These relative positives of the middle term in the premises,
constitute, I repeat, what are called the ^our Syllogistic Fig-
ures {(TXTjiuvra, Jigune) ; and these positions I have comprised in
the two following mnemonic lines.
In Comprehension.
Pns sub ; turn pne prcs ; turn sub sub ; deniqufi sub pros.
In Extension.
Sub prcE : turn prce prce ; turn sub sub ; denique pra sub.*
1 Cf. Krug, Logik, 4 104. — Ed.
2 This formula for Extension is taken from
Purchot, Inst. Phil., Logiea, t. I. o. iil. p. 188
Tl'.e other line is the Author's own. — Ed.
Lect. XX. LOGIC. S83
Of these two kinds of irregularity in the external form of syllo-
gisms, the former — that of propositions — is
p caion. of far less importance than the latter — that of
Irregularity in the t-
external form of syi- terms; and logicians have even thrown it alto-
logism, arising from gether out of account, in their consideration of
transposition of the gyllogistic Figure. They are, however, equally
Propositions. '' ° . . "^ , .
wrong m passmg over the irregular consecution
of the propositions of a syllogism, as a matter of absolutely no mo-
ment; and in attributing an exaggerated im-
Thatasy ogismcan portance to every variety in the arrangement
be perspicuously ex- „ . m
pressed by any of the ^f its terms. They ought at least to have made
live irregular consecu- the studcnt of Logic aware, that a syllogism can
tions of Its Proposi- jjg perspicuously expressed not only by the nor-
mal, but by any of the five consecutions of its
propositions which deviate from the regular order. For example,
take the following syllogism :
AU virtue is praiseworthy ;
But sobriety is a virtue;
Therefore, sobriety is praiseworthy.
This is the regular succession of sumption, subsumption, and con-
clusion, in a syllogism of extension ; and as all that can be said, on
the present question, of the one quantity, is applicable, mutatis
mutandis, to the other, it will be needless to show articulately that
a syllogism in comprehension is equally susceptible of a transposi-
tion of its propositions as a syllogism in extension. Keeping the
same quantity, to wit, extension, let us first reverse the premises-
leaving the conclusion in the last place (B, A, C).
Sobriety is a virtue ;
But all virtue is praiseworthy ;
Therefore, sobriety is praiseworthy.
This, it will be allowed, is sufficiently perspicuous. Let us now
enounce the conclusion before the premises ; and, under this head
let the premises be first taken in their natural order (C, A, B).
Sobriety is praiseworthy ;
For all virtue is praiseworthy ;
And sobriety is a virtue.
Now let the premises be transposed (C, B, A).
^ LOGIC. Ljxt. x:^
Sobriety is praiseworthy /
For sobriety is p. virtue ;
4.nd all virtue is prvjsewoHhj/.
The regressive reasoning in botti these pases is not less manifest
than the progressive reasoning of the regular order.
In the last place, lot us inteqwlate the conclusion betweea th«
premises in their normal consecation (A, C, B).
JLH virtue is prcdsevcor^ ;
Therefore, sobriety is praittworthy ;
For sobriety is a virtue.
Secondly, between the premises in their reversed ot4er (B, C, A).
Sobriety is a virtue;
Therefore, sobriety is praiseworthy ;
For aU virtue is praiseworthyA
In these two cases the reasoning is not obscure, though perhaps
the expression be inelegant; for the judgment placed after the con-
clusion had probably been already supplied in thought on the enun-
ciation of the conclusion, and, therefore, when subsequently ex-
pressed, it Is felt as superfluous. But this is a circumstance of no
logical importance.
It is thus manifest, that, though worthy of notice in a system of
Logic, the transposition of the propositions of a syllogism affords
no modifications of form yielding more than a superficial character.
Logicians, therefore, were not wrong in excluding the order of the
propositions as a ground on which to constitute a difference of syl-
logistic form: but we shall see that they have not been consistent,
or not sufficiently sharp-sighted, in this exclusion ; for several of
their recognized varieties of form — several of the moods of syllo-
gistic figure — consist in nothing but a reversal of the premises.
In reality, however, there is no irregular order of the syllogistic
propositions, except in the single case where the
True doctrine of con- conclusion is placed between the premises. For
'^k.^«m either sy«. * syUogism may be either called Sf/niAetic, iu
tnetio or Anal) tic. casc thc premises come first, and the conclusion
is last — (the case alone contemplated by thc
logicians) ; or it may be called Analtftic^ the proposition styled the
conclusion preceding, the proposiiious called the premises following,
as its reasons — (a case not contemplated by the logicians). The
1 Cr. Krag, I^f lA;, ) 104, Anmerk, i. — Eo.
Lect. XX. .LOGIC. 285
Analytic and Synthetic syllogisms ttiay again be each considered
as in the quantity of Extension, or as in the quantity of Compre-
hension ; in which cases, we shall have a counter-order of the prem-
ises, but of which orders, as indeed of such quantities, one alone
has been considered by the logicians.
I now, therefore, go on to the second and more important ground
of regularity and irregularity — the natural and
The natural and transposed order of the Syllogistic Terms. The
irsTiTogltrxerms"/ ^^^ms deteiTuined by the^ different position of
the middle term by relation to the major and
minor terms in the premises of a syllogism are called Figures ((txt
uara, fiqi(rm) — a name given to them by Aris-
Figures of Syllogism. ^ ,*^ ^^ _ /, , v ^ . • ., , -
totle.^ Of these the nrst is, on the prevalent
doctrine, not properly a figure at all, if by figure be meant in Logic,
as in Grammar and Rhetoric, a deviation from the natural and reg-
ular form of expression. Of these figures the
h*ib^A**t ti"* ^^^* three were distinguished by Aristotle, who
developed their rules with a tedious minuteness
sometimes obscure, and not always in the best order, but altogether
with an acuteness which, if ever equalled, has certainly never been
surpassed. The fourth, which Whately — at
Fourth Figareattrib- jg^g^ -^^ ^^^ former editions of his Elements —
uted to Galen, but on , , /-v /» i i • •
slender authority. ^°^ Other recent Oxford logicians seem to sup-
pose to be, like the others, of Aristotelic origin,
— we owe perhaps to the ingenuity of Galen. I say perhaps, for
though in logical treatises attributed without hesitation to the great
physician, as if a doctrine to be found in his works, this is altogether
erroneous. There is, I am certain, no mention of the fourth figure
in any writing of Galen now extant, and no mention of Galen's
addition of that figure by any Greek or Lit'cin authority of an age
approximating to his own. The first notice of this Galenic Figure
is by the Spanish Arabian, AveiToes of Cordova,
First ascribed to Ga- • i • x ^i. ^o a a ^
... in his commentary on the Orqanon.' Averroes
Jen by Averroes. _ *' , "^
flourished above a thousand years posterior to
Galen; and from his rejwrt alone (as I have also ascertained) does
the ])revnlent opinion take its rise, that we owe to Galen this ampli-
fication (or corruption, as it may be) of the Aristotelic doctrines of
logical figure. There has been lately published from manuscript,
by Didot of Paris, a new logical treatise of Galen.^ In this work,
in which the syllogistic figures are detailed, there is no mention of
1 Anal. Prior , 1. 4. — Ed. [Of. Pacing, Com- " YaXiivov EiVaycoT^ AtoAerrorii — i*
mem., pp. 118, 122.] Uaoiaitf au/JtS' (1844) — Ed.
2 Prior Analytics, [B. i. oh 8. — Ed.]
286 LOGIC. Lkct. XX
a fourth figure. Galen, therefore, as far as we know, affords no
exception to the other authors upon Logic. In these circumstances,
it is needless to observe how slender isthe testimony in favor of the
report ; and this is one of many others in which an idle story, once
told and retailed, obtains universal credit as an established fact, in
consequence of the prevalent ignorance of the futility of its foun-
dation. Of the legitimacy of the Fourth Figure I shall speak, after
having shown you the nature of its reasoning.
Before proceeding, further in the considera-
compiex modifica- tj^jj ^f ^^jg Figure of Syllogism, it is, however,
tlon of the Figure of ♦ ^ ♦ i ;i-c *• *
Syiioirism. necessary to state a complex modmcation to
which it is subject, and which is contained in
the following paragraph.
% LXXrV. The Figure of Syllogism is modified by the
Quantity and Quality of the propositions
sutioicoo^ ^'"*^ which constitute the reasoning. As the
combination of Quantity and Quality af-
fords four kinds of propositions — Universal Affirmative (A),
Universal Negative (E), Particular Affirmative (I), Particular
Negative (O) ; and as there are three propositions in each syl-
logism, there are consequently in all sixty-four arrangements
possible of three propositions, differing in quantity and quality ;
— arrangements which constitute what are called the Syllogis-
tic Moods (rpoTToi, modi). I may interpolate the observation :
The Greek logicians after Aristotle, looking merely to the two
premises in combination, called these Syzygies (irwfvyuu, juga-
tiones, conjugationes^ combinationes). Aristotle himself never
uses TpoTTos for either mood or modality specially ; nor does he
use (Tvi,vyla in any definite sense. His only word for mood is
the vague expression syllogism.
The greater number of these moods are, however, incompe-
tent, as contradictory of the general rules of syllogism ; and
there are in all only eleven which can possibly enter a legiti-
mate syllogism. These eleven moods again are, for the same
reason, not all admissible in every figure, but six only in each,
that is, in all twenty-four ; and again of these twenty-four, five
are useless, and, therefore, usually neglected, as having a par-
ticular conclusion where a universal is competent. The nine-
teen useful moods admitted by logicians may, however, by the
quantification of the predicate, be still further simplified, by
superseding the significance of Figure.
Lect. XX. LOGIC. 287
In entering on the consideration of the various Moods of the
Sylloffistic Figures, it is necessary that you re-
call to memory the three laws I gave you ot the
Categorical Syllogism, and in particular the two clauses of the sec-
ond law, — That the sumption must be definite (general or singu-
lar), and the subsumption afiii-mative, — clauses which are more
vaguely expressed by the two laws of the logicians — that no con-
clusion can be drawn from two particular premises — and that no
conclusion can be drawn from two negative premises. This being
premised, you recollect that the four combinations of Quantity and
Quality, competent to a proposition, were designated by the four
letters, A, E, I, O, — A denoting a universal affirmative; — E a
universal negative; — I, a particular affirmative; — O, a particular
negative.
AsseritA; negatE; veram universallter amb»:
Assent I; negatO; sed particulariter ambo.l
A, it afflrms of this, these, all ;
As E denies of any :
I, it affirms, as O denies,
Of some, or few, or many.
Thus A affirms what E denies.
And definitely either;
Thus I affirms what O denies.
But definitely neither.*
Now, as each syllogism has two premises,
The possib e com i- ^here are, consequently, sixte'eu different corn-
nations of premises. -^ .
binations possible of premises differing in quan-
tity and quality — viz. :
A A.
2)EA.
3) I A.
4)0 A.
AE.
EE.
IE.
OE.
AL
EI.
II.
OL
AO.
EO.
10.
0 0.
Now the question ai'ises — are all of these sixteen possible com-
binations of different premises valid towards a legitimate conclu-
sion? In answer to this, it is evident that a considerable number
1 See above, p. 180. — Ed. — Wilson, RuU of Reason, p. 27 a, 1551.
2 [The following are previous English met- .. ^ ,^y^ ^^^ ^ ^^^.^^, ^^^ j^^^,,^
rical versions of these lines : I „y, ^^^ q denies, both partially."
" A doeth afflrme, E doeth denigh, which are bothe . _ .. .
universall: — Wallis, Institutio Logiae, 16S6, L. U. C. 4, p
1 doeth afflrme, O doeth denigli, which wc particn- 105.]
Ur call."
LOGIC.
Lkct. XX.
How many of these
are syllogistically val-
M.
of these ai*e at once invalidated by the first claase of the second
law of the categorical syllogism, in so far as
recognized by logicians, by which all moods with
two particular premises are excluded, as in these
there is no general rule. Of this class are the
four moods, I I, I O, O I, and O O. And the second clause of
the same law, in so far as recognized by logicians, invalidates the
moods of two negative premises, as in these there is no subordina-
tion. Of this class are the four moods E E, E O, O E, and O O.
Finally, by the two clauses of the second rule in conjunction, the
mood I E is said to be excluded, because the particuhir sumption
contains no general rule, and the negative snbsumption no subordi-
nation. (This, I think, is incorrect.) These exclusions have been
admitted to be valid for every Figure; there, consequently, remain
(say the logicians) as the possible modes of any legitimate syllogism,
the eight following — A A, A E, A I, A O, E A, E I, I A, O A ; '
but some of these, as apparently contradictory of the second rule in
its more definite assertions, — that the suUiption must be general
and the subsuniption affirmative, — I shall, after stating to you the
common doctrine of the logicians, show to be really no exceptions.
But whether each of the moods, though a jyriori possible, affords
a proper syllogism in all the figures — this de-
pends on the definite relations of the middle
term to the two others in the several figures.
These, therefore, require a closer investigation.
I shall consider them, with the logicians, princi-
j)ally in the quantity of extension, but, mutatie mutandis^ all that
is true in the one quantity is equally true in the other.
Now if, in the first figure, we consider these eight moods with
reference to the general rules, we shall find that
all do Aot in this figure afford correct syllogisms;
but only those which are constructed in conformity to the follow-
ing particular rules, which are, however, in this figure, identical with
those we have already given as general laws of every perfect and
regular categorical syllogism.
The symbol of the First Figure is, —
Whether each mood
that is a priori possible
affords a proper syllo-
gism in ail the figures.
First Figure.
S M I for Extension ; ^ p' | for Comprehension.
The first rule is, — " The sumption must be universal. Were U
particular, and, consequently, the subsumption universal, as;
1 Cf. Baobmaan, Litgik, ( 129. — Ed.
Lect. XX. LOGIC. 289
Some M are P;
ButaUSareH;
we could not know whether S were precisely the part of M which
lies in P, and it might be altogether out of P. In that case, a uni
versal negative conclusion would be the correct ; but this cannot
be drawn, as there is no negative premise, and though accident-
ally perhaps true, still it is not a necessary consequence of the
premises." ^
" The second rule is, — The subsumption must be affirmative.
Were it negative, and consequently the sumption affirmative, in
that case S would be wholly excluded from the sphere of M ; and,
consequently, the general rule under which M stands would not be
applicable to S. Thus :
AUMareF;
NoSisTA;
No S i» P.
AH colors are physical pJuenomena ;
No sound is a color;
Therefore, no sound is a physical phcenomenon.
"Here the negative conclusion is filse, but the affirmative, whioh-
would be true, — all sounds are physical phcenomena^ — cannot be
inferred from the premises, and, therefore, no inference is competent
at all." 2
Thus, in this figure, of the eight moods generally admissible, I A
and O A are excluded by the first ; A E and
LegiUmate moods of A O by the second rule. There remain, there-
^'"xhlrsynibois. ^•^'*^' ^^^Y ^^^^ legitimate moods, A A, E A,,
A T, and E I. The lower Greek logicians de-
noted them by the terms, —
rpd/ifiaTUf ''Eypa^f, rpa(pi5i, T€xytK6s ; '
the Latin schoolmen by the terms —
Barbara, Celareni, DarU, and Ferio.
1 Bachmann, Logik, t 130, p. 203. — Ed. 2 Bachmann, as abore. — Ed. [Cf. Dero-
[So Hollmann, Phil. Rationalis, qutz Logica don, Logica Restiluta,'P. ir. p. 618. Ulricb, at
vulgo dicitur, § 461, Gottingse, 1V46. Lovani- above. Lovanienses, as above. Hollmann,
enses, Commentaria in hag. Porphyrii tt in Logica, § 462.]
ornnes Libros Arist. de DiaUctiea, Anal. Prior, L.
i. p. 215, Lovanii, 1547. Ulrich, Instit. Log. 3 For an account of these mnemonic^.
et Mel., f 191, lense, 1785. Fonseca, Instit. see i>ucuMtoiu, p. 671, second edition. — Ed.
Dial., L. vi. c. 21, p. 363.]
37
B90
LOGIC.
Lect. XX.
In the Latin symbols, which are far more ingenious and complete,
and in regard to the history of which I shall say something in the
sequel, the vowels are alone at present to be considered, and of
these the first expresses the sumption, the second the subsumption,
and the third the conclusion. The correctness of these is shown
by the following examples and delineations.
" The first mood of this figure :
I. Barbara.
I. Basbaba.
AUiiartP;
AUSareU;
Thenfore, afl S ar« P.
AU that » composite is dismluble ;
AU material things are composite ;
Ther^ore, all material things are ditaobttiU.
n. Cclarant
m. DwlL
W)
IL Cblakbht.
AbMwP;
AnSareJA;
There/ore, no 8 is T.
No finite being is exempt from emr;
AU men are finite beings ;
TTherrfore, no man is exenq>t from emr.
m. Darii.
AUVLarePi
Some SoreM;
Thertfore, some S are P.
AU virtues are laudMe;
Some habits are virtues ;
Ther^ore, some habits are laudable.
"This diagram makes it manifest to the eye why the conclusion
can only be particular. As only a part of the sphere S lies in the
gphero M, this part must lie in the sphere P, as the whole of M lies
therein ; but it is of this part only that anything can be affirmed in
the conclusion. The other part of S can cither lie wholly out of
P, or partly in P but out of M; but as the premises affirm nothing
of this part, the conclusion cannot, therefore, include \t.
Lect. XX.
IV. Feria
LOGIC.
IV. Febio.
NoUisF;
Some S are M ; •
Therefore, some S are not P.
No virtue is reprehensible ;
Some habits are virtues ;
Thartfore, some habits are tiot reprehensible.
291
0
" The conclusion in this case can only be particular, as only a part
of S is placed in the sphere of M. The other part of S may lie out
of P or in P, But of this the premises determine nothing." ^
Second Figure. The symbol of the Second Figure is —
PM,
SM,
for Extension ;
SM,
PM,
for Comprehension.
Itsmles.
♦* This figure is governed by the two following
rules. Of these the first is — One premise must
be negative.* For were there two affirmative premises, as :
AUFareM;
AUSareil;
All metals are minerals ;
AU pebbles are minerals ;
the conclusion would be — All pebbles are metals^ which would be
false.
" The second rule is : — The sumption must be universal.^ Were
1 Bachmann, Xofiik, p. 204— 206. — Ed. Scotns.] [Quetstionts in Anal. Prior., l„\.i^
2 [See Derodon, Lo^ka Restituta, P. ir. p. 20, f. 268. — Ed.]
637. HoUmann, Logiea, §; 4G3, 464. Lorani- ,3 See Uollmann, and Lovanienses, asciteti
enses, Com. in Arist. Anai. Prior., h. i. p. 21B. abov«. — £d.
LOGIC.
Lkct. XX.
the sumption particular, the snl^sumption hehooved to be uniyersal ;
for otherwise no conclusion would be possible. But in that case the
gumption, whether affirmative or negative, would afibrd only aa
absurd conclusion.^
« If affirmative, as —
Some P are M ;
AbSwM;
Therefore, some S are not P.
Some ammcda lay eggs, i. e. are egg^ying tJang$j
No horse lays eggs, i. e. is any egg-laying thing;
Tlierefore, some horses are not aniwkoU.
"If negative, as —
Some P ore tu3< M;
AMSare'U.;
Ther^ore, some S are not P.
Some minerals are not precious stones;
An topazes are precious stones ;
Ther^ore, some topazes are not minerals ;
in both cases the conclusion is absurd.
"There thus remain," say the logicians, "only the moods Cesar6f
Camestresy Festino^ JBaroco.
I. Cetare.
I. Cbsabb.
AbPitH;
JOS ore M;
Therefore, no S tf P.
Nothing material has free wHt;
AH spirits have free will;
Ther^ore, no spirit is materiaL
n. Camestica.
H. Camestrbs.
AHFareM;
NoSu M;
Uterrfore, no 8 is P.
An colors are visible ;
No sound is visible ;
Thertfore, no sound is a odor.
I [C£ Fonaeoa, hutit. DimL, L. tL «. », p. 9tS.}
Lect. XX-
L06IC.
29$
III. Feetino.
JVoPisM;
Some S are M;
Therefore, some S are fu* P.
in. Festiko.
No vice is praiseworthy;
Some actions are praiseworthy ;
Therefore, some actions are not vten.
" The diagram here is alternative, for as the conclusion can only
comprise a part of S, as it is only the consequence of a partial sub-
ordination of S to M, the other parts of S which are out of M may
either lie within or without P. — The conclusion can, therefore, only
be particular.
IV. Baroco.
rv. baboco.
AUTareyi;
Some S are not M ;
Therefore, some S are not P.
AU birds are oviparous ;
Some animals are not oviparous ;
Therefore, some animals are not birds." *
1 Bacbmann, Logik, as above. — Bd.
LECTURE XXI.
STOIOHEIOLOGY.
SECTION II. — OF THE PRODUCTS OF THOUGHT
ni, — DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO EXTERNAL
iX)RM.
FIGURE — THIRD AND FOURTH.
In our last Lecture, after terminating the general consideration
of the nature of Figure and Mood in Categorical
Syllogisms, we were engaged in a rapid survey
of the nineteen legitimate and useful moods belonging to the four
figures, according to the received doctrine of logicians (conse-
quently, exclusively in Extension) ; and I had displayed to you
the 'laws and moods of the First and Second B'igures. Before, there-
fore, proceeding to any criticism of this doctrine, it behooves us to
terminate the view of the two remaining figures.
To each of the first two figures, logicians at-
tribute four moods ; to the third they concede
six ; and to the fourth five. The scheme of the Third Figure, in
Extension, is —
MP,
M S.
This figure (always in extension) is governed by the two follow-
ing laws : — the first is, " The subsumption
must be affirmative.^ Were the minor premise a
negative, as in the syllogism, —
Third rigure.
It« rules.
AUJAareF;
iVoMtsS;
AU fiddles are musical instruments ;
But no fiddle is a flute;
I [Sm Aristotle, Anal. Prior., i. 6, (f 8| 16- UoIImann, Logiea, f 466. LoTanienaes, Ik Am.
PHor.L. i. P.220.J
Lkct. XXI. LOGIC. 295
here the conclusion would be ridiculous, — Therefore^ no S is P, —
Therefore^ no flute is a musical instrument. For M and S can both
exclude each other, and yet both lie within the sphere of P.
" The second law is, — The conclusion must be particular, and
particular although both premises are universal.* This may be
shown both in affirmative and negative syllogisms. In the case of
affirmative syllogisms, as:
^HMarcP;
But aU 'Hare S;
here, you will observe, M lies in two different spheres — P and S,
and these must in the conclusion be connected in a relation of sub-
ordination. But S and P may be disparate notions,^ and, con-
sequently, not to be so connected ; an absurd conclusion would,
therefore, be the result. For example, —
AU birds are animals with feathers ;
But an birds are animals with a heart ;
Therefore, aU animals with a heart are animals with feathers.
" Again," say the logicians, " in regard to negatives : — In these
only the sumption can be negative, as the subsumption (by the first
rule) must be affirmative. Thus :
NoHisP; No silver is iron : '
or,
But all M are S ; But all silver is a mineral.
" Here the conclusion — No S is P, — iVb mineral is iron, would
be false,
" Testing the eight possible moods in Extension by these special
rules, there remain for this figure, six, which by the Latin logicians
have been named, Darapti, Felapton, Disamis, Datisi^ Bocardo^
Ferison. The first mood of this figure is :
I Darapti. I. Dabapti.'
An. M are P; y»^ v
ButaR MareS;
Therefore, some S are P;
or.
All gilding is metallic ;
AU gilding shines ; \ /
Therefore, some things that shine are metoBic. X^^ _,,^
&:)
1 [But Bee HollmaBD, Logiea, H 332, 458. the comprehension of their common Fubjeot
Loranienses, In An. Priar.^ L. i. p. 220.] M. See above, p. 158. — Ed.
2 Disparate notions, i. t., coordinate parts of 8 [Some of the ancient logicians, among
296
LOGIC.
Lect. xxr.
" Here it Is manifest that M cannot at once lie in two different
spheres, unless these partially involve, partially intersect each other.
But only partially ; for as both P and S are more extensive than M,
and are both only connected through M {i. e. through a part of
themselves), they cannot, except partially, be identified with each
other.
" The second mood of this figure is, —
II. Felapton. II. Felapto».*
No M IS P;
ButaflMareS;
Therefore, some S are not P;
or.
No mateiial substance is a moral suttject ;
But all that is material is extended ;
Therefore, something extended is not a moral subject.
"You will observe, that according to this diagram, the conclusion
ought to be — No S is P, because the whole of S lies out of the
sphere of P; and as in the concrete example, the notion extended
is viewed as out of the notion moral subject, we might conclude, —
Nothing extended is a moral subject. But this conclusion, though
materially correct, cannot, however, be formally inferred from the
premises. In the sumption, indeed, the whole of M is excluded
from the sphere of P ; but in the subsumption M is included in the
sphere S, that is, we think that the notion M is a part of the notion
S. Now in the conclusion, S is brought under P, and the conclusion
of a categorical syllogism, in reference to its quantity, is, as you
remember, by the third general law regulated by the quality of the
subsumption. But as in the present case the subsumption, notwith-
Btanding the universality of the expression, only judges of apart of
others Porphyry, have made two moods of
Dampti, as Aristotle himself docs in Cesare
and Cameittres, in Di.«amis and Datisi. See
Uocthiiifi, Df SyUngismo Calrgnrifo, L. ii.. Op-
em, p 694 alibi. Cf Zabarella, Opera Logica,
Df Quarta Figura Si/Uog., pp. 119, 120 tt srq.
Alex. Aphrodisiensis, In Anal. Prior., i. 6, ff.
28, 24, Aid. 1631. Phlloponns, In Anal. Pnor.,
L. i. C. 6, f. 18 b. Apulcius. De Habitwi. Doct.
Plat., L. ill. Opera, p. 87, 88, ed. Elmenhorst.)
1 [Aristotle gives Fapemo, A-al. Prior. J. 7-
(Burgersdyck, Instit. Logica, L. il 0. 7| p-
169, Cantak, 1647.)]
XXI.
LOGIC.
297
S ; the conclusion can, in like manner, only judge of a part of S.
Of the other parts of S there is nothing enounced in the premises.
The relation between S and P could likewise be as follows :
No M is P;
But all M arc S;
or,
No pigeon is a hawk;
But ail pigeons are birds ;
" Here the conclusion could not be a universal negatise, — There-
fore^ no S is P, — Therefore, no bird is a hawk — for the sphere of
S (bird) is greater than that of either M (pigeon) or P (hawk); it
may, however, be a particular negative — Therefore, some S are not
P (therefore, some birds are not hawks), — because the sumption
has excluded M and P (pigeon and hawk) from each other's sphere,
and, consequently, the part of S which is equal to M is diflferent
from the part of S which is equal to P. — But if this be the case
when the subsumption has a universal expression, the same, a for-
tiori, is true when it is particular.
" The third mode of this figure is :
III. Disamis III. DiSAMis.
Some. M are P ;
But all M are S ;
Therefore, some S are P;
or,
Some acts of homicide are laudable ;
But aU acts of homicide are crtiel;
Therefore, some cruel acts are laudable.
" The fourth mood of this figure is :
IV. Datisi. IV. Datisi.
^ZZMareP;
But some M are S ;
Therefore, some S are P ;
or,
AU acts of homicide are cruel ;
Some acts of homicide are laudable ;
Therefore, some laudable acts are cruel.
38
298
LOGIC
Lect. XXL
' This diagram makes it manifest that more than a single case is
possible in this mood. As the subsumption is particular, the con-
slusion can only bring that part of S which is M into identity with
P; of the other parts of P there can be nothing determined, and
these other parts, it is evident, may either lie wholly out o^ or
partly within, P.
" The fifth mood of this figure is :
V. Bocardo.
V. BOCARIK).
Some M are not P;
But da in are S;
Therefore, some S are not P;
or,
Some syllogisms are not regular;
But all syllogisms are things important ;
Thertifore, some important things are not things regular.
" The sixth mood of this figure is :
VI. Ferison. VL FEBigOK.
JVbMisP;
But some M are S ;
Therefore, some S ore not P;
or,
No truth is wUhout result ;
Some truths are misunderstood ;
Therefore, some things misunderstood are not without reguU.
or,
"Here, as in the premises, only that part of S which is M is
excluded from P, consequently the other parts of S may either like-
wise lie wholly out of P, or partially in P." ^ '
So much for the moods of the third fiffure.
1 Bacbmann, LosUc, i 132, p. 211— 218. — £d.
Lect. XXL LOGIC. 299
Fourth Figure. " The formula of the Fourth Figure is :
M S.
Its Laws. « Tijis figure is regulated by three laws.
" I. Of these the first is, — If the sumption be affirmative, the
subsumption must be universal. The necessity of this law is easily
seen. For if we had the premises :
AUFareii;
But some M are S;
in this case M may, or may not, be ^ notion superior to P.
" On the former alternative, if M be higher than P, and likewise
higher than S, then the whole of S might be contained under P. —
In this case, the proper conclusion would be a universal affirmative ;
which, however, cannot follow from the premises, as the subsump-
tion, ex hypothesi, is particular. On the latter alternative, even if M
were not superior to S, still, since P is only a part of M, we could
not know whether a part of S were contained under P or not. For
example :
AU men are animals ;
But some animals are amphibious.
" From these premises no conclusion could be drawn.
"II. The second rule by which this figure is governed is — If
either premise be negative, the sumption must be universal.
"Suppose we had the premises —
Some P are not M ;
But aU 'ill are Si
Therefore, some S are not P;
or.
Some animals are not feathered;
But all feathered aniinals are birds ;
Therefore, some birds are not animals.
" In this case the whole of S lies within the sphere of P ; there
cannot, therefore, follow a particular negative conclusion, and if
not that, no conclusion at all. The same would happen were the
sumption a particular affirmative, and the subsumption a universal
negative.
" III. The third rule of the fourth figure is — If the subsumption
300
LOGIC.
Lect. XXL
he affirmative, the conclusion must be particular. This (the logi-
cians say) is manifest. For in this figure S is higher than M, and
higher than P, consequently only a part of S can be P.
" If we test by these rules the eight possible moods, there are m
this figure five found competent, which, among sundry other names,
have obtained the following: ^ramantip, Camenes^ DimariSy
JP^esapo, Fresison.
" Of these moods the first is :
I Bramantip.
I. Bbahantip, otherwise Bahalip, etc
All U arc S;
Therefore, sonve S ore P;
AU greyhounds are dogs ;
But all dogs are quadrupeds ;
Therefore, some quadrupeds are grei/hounds.
" The second mood is called :
II. Camenea. n. Camehes, Calehes, or Calektes, etc
AUFareU;
BiUnoJtlisS;
Therrfore, no S if P;
or,
AU ruminating animals hatx four stomachs ;
But no animal with four stomachs is camivorotu ;
Thertfore, no carnivorous animal ruminates.
"The third mood in the fourth figure is variously denominated:
III. Dimaria.
in. DiMARis, or DiHATis, Of DiBATis, etc
Some P are M ;
ButaUUareS;
Therefore, some 8 are P;
or,
Some practicaUy virtuous men are necessitmriaiu ;
All necessitarians speculatively subvert the distinction of vice and
virtue ;
Therefore, some who speculativdy subvert the distinction qf via
and virtue are practically virtuous men.
"The fourth mood of this figure is:
Lkct. XXI.
rV. Fesapo.
LOGIC.
IV. Fbsapo.
iVoPisM;
All M are S;
Therefore, some S are not P;
or,
No negro is a Hindoo ;
But aO Hindoos are blacks;
Therefore, some blacks are not negroes ;
301
O©
or,
" According to the first of these diagrams, all S is excluded from
P, and thus the conclusion would seem warranted that — No S is
P. This conclusion cannot, however, be inferred ; for it would vio-
late the third rule of this figure. For while we, in the sumption,
have only excluded M, that is, a part of S, from P, and'as the other
parts of S are not taken into account, we are, consequently, not
entitled to deny these of P. The first diagi-am, therefore, which
sensualizes only a single case, is not coadequate with the logical
formula, and it is necessary to add the second in order to exhaust
it. The second diagram is, therefore, likewise a sensib^le represen-
tation of Fesapo ; and that diagram makes it evident that the con-
clusion can only be a particular negative.
" The fifth and last mood is ;
V. Fresiion. V. Fresison.
• iVbPisM;
But some "Mare S;
Thertfore, some S are not P;
or,
JVo moral principle is an animal impulse ;
But some animal impulses are principles of action ;
Therefore, some principles of action are not moral prindplet.
or,
30B LOGIC. Lect. XXI.
" The demonstration is here the same as in the former mood.
Since the subsuniption only places a part of M in the sphere of S,
the conclusion, whose quantity is determined by the subsumption,
can only deny P of that part of S which is likewise a part of M."'
Having thus concluded the exposition of the various Figures and
Moods of Syllogisms, as recognized by logicians.
0 an ignre in j^ reference to Extensive Quantity, it will not
Comprehension. .
be necessary to say more than a word in general,
touching these figures and moods in reference to Comprehensive
Quantity. Whatever mood and figure is valid and regular in the
one, is valid and regular in the other ; and every anomaly is equally
an anomaly in both. The rules of the various figures which we
have considered in regard to syllogisms in Extension, are all, with-
out exception or qualification, applicable to syllogisms in Compre-
hension, with this single proviso, that, as the same proposition forms
a different premise in the several quantities, all that is said of the
sumption in extension, should be understood of the subsumption in
comprehension, and all that is said of the sumption in comprehen-
sion, shoul(f be understood of the subsumption in extension. What,
therefore, has hitherto been, or may hereafter be, stated of the mood
and figure of one quantity, is to be viewed as applicable, mutatis
mutandis, to the other. This being understood, I proceed, in the
fii"st place, to show you that the complex series
Criticism of the ^f logical forms which I have enumerated may
loeicai' forms ' " ^^ Considerably diminished, and the doctrine of
syllogism, consequently, reduced to a higher
simplicity. In doing this I shall consider, firet, the Figures, and,
secondly, their Moods.
Now, as regards the number of the Figures, you are aware, from
1 The FiKures. what I formerly stated, that Aristotle only con-
templated the three first, and that the fourth,
which is, by those who do not mistake it for an
Aristotelic form, referred with little probability to Galen, was wholly
unnoticed until the end of the twelfth or tjie beginning of the thir-
teenth century, when it was incidentally communicated, as an inno-
vation of the physician of Pergamus, by the celebrated Averroes, in
his commentary on the Prior Analytics of Aristotle, but by Aver-
roes himself rejected as an illegitimate novelty.* The notice of this
figure by the commentator was, however, enough ; and though re-
pudiated by the great majority of the rigid Aristotelians, the author-
1 Bacbmann, Logik, i 188, p. 218—223.— 2 In Anal Prior, 1%. Opaa ilmtwtdi*, t. i>
£o. f . 78. VenctUs, 1600. — £d.
Lkct. XXI. LOGIC. 303
ity of Scotus, by whom it was defended/ secured for it at last, if not
a universal approval, at least a very general toleration, as a legiti-
mate though an awkward form. The arguments indeed by which
it was attempted to evince the incompetency of this figure, were
not of a character calculated to enforce assent ; for its inference is
not less valid than that of any other, — however tortuous and per-
verse it may be felt to be. In fict, the logicians, in consequence of
their exclusive recognition of the reasoning in extension, were not in
possession of the means of showing, that this figure is a monster un-
deserving of toleration, fur less of countenance and favor. I shall not,
therefore, trouble you with the inconclusive reasoning on the part
either of those who have assailed or of those who have defended
this figure, but shall at once put you in possession of the ground on
which alone, I think, its claim to recognition ought to be disallowed.
In the first place, then, you are aware that all reasoning is either
in the quantity of comprehension, or in the
Grounds on winch quantity of extension. You are aware, in the
ou'ht to be disallowed sccoud, that thcsc quantities are not only differ-
ent, but, as existing in an inverse ratio of each
other, opposed. Finally, in the third place, you are aware that,
though opposed, so that the maximum of the one is the minimum
of the other, yet the existence of each supposes the existence of the
other ; accordingly there can be no extension without some compre-
hension, — no comprehension without some extension.
This being the case, it is evident that, besides the definite reason-
ing from whole to part, and from parts to whole,
A cross inference \^rithin the Several quantities and in their per-
possible from Exten- f ^ i- ^i • i ^ ^
. . „ , pendicular lines, there is also competent an in-
8ion to Comprehen- ^ ' ^ ^
sion and vice versa. definite inference across from the one quantity to
the other. For if the existence of the one quan-
tity be only possible under the condition of the other, we may
always, it is self-evident, in the first place, from the afiirmation of
anything in extension, indefinitely aflSrm it in comprehension, as,
reciprocally, from the affirmation of anything in comprehension, we
may indefinitely affirm it in extension ; and, in the second place,
from the negation of anything in extension, we may absolutely deny
1 This statement is marked as doubtful in conclusionis: per consequens nee diversitas
the Author's Common-place Book. Scotus figures."
( Qti^st. in Anal. Prior., i. q. 34) expressly re- The Fourth Figure is, however, said by
jects the Fourth Figure. He says: " Solum Ridiger {De Sensu Yeri et Falsi, p. 337) to have
tribus modis potest fieri debita ordinatio re- been introduced by Galen and Scotus. IIos-
Fpectu e.xtremorum secundum subjictionem pinianus (De Controversiis Dinlecticis, c. xix.)
et prasdicationem ; igltur tres figuraj et non attributes (erroneously) the invention of this
plurcs .... quia per solam transpositionem figure to Scotus. Compare also Noldius,
r.on pervenit diversitas allcujus pra-missa: nee Logica Recognita, c. xiii. i 4, p. 277- — Ed.
304
LOGIC.
Lect. XXI
This the nature of
the inference in the
Fourth Figure.
it in compreh<^nsion, as, reciprocally, from the negation of anything
in comprehension, we may absolutely deny it in extension.
Now, what has not been observed, such is exclusively the infer-
ence in the Fourth Figure ; its two last rules
are in fact nothing but an enunciation of these
two conditions of a cross inference from the one
quantity to the other ; and the first rule will be
hereafter shown to be only an error, the result of not observing that
certain moods are only founded on the accident of a transposed
order of the premises, and, therefore, constitute no subject for a logi-
cal legislation.
To prove this statement of the nature of the inference in the
Trored and iiiustra- fourth figure, it is only necessary to look at its
ted. abstract formula. In extension this is —
P is M;
M ts S;
8 IS P.
Here in the premises P is contained under M, and M is contained
under S ; that is, in the premises S is the greatest whole and P the
smallest part. So far, this syllogism in extension is properly a syl-
logism in comprehension, in which the subject of the conclusion is
the greatest whole, and its predicate the smallest part. From such
premises we, therefore, expect, that the conclusion carrying out what
was established in the antecedent, should affirm P as the part of S.
In this, however, our expectation is disappointed; for the reasoning
suddenly turns round in the conclusion, and affirms S as a part of P.
And how, it may be asked, is this evolution in the conclusion com-
petent, seeing that it was not prepared, and no warrant given for it
in the premises. To this the answer is prompt and easy. The con-
clusion in this figure is solely legitimated by the circumstance, that
from an identity between the two terms in one quantity, we may
always infer some identity between them in the other, and from a
non-identity between them in one quantity, we can always infer a
non-identity in the other. And that in this figure there is always
a transition in the conclusion from the one quantity, is evident ; for
that notion which in the premises was the greatest whole, becomes
in the conclusion the smallest part ; and that notion which in the
premises was the smallest part, becomes in the conclusion the great-
est whole. Now, how is this manoeuvre possible? — how are we
entitled to say that because A contains all B, therefore B contains
some A ? Only, it is clear, because there is here a change from the
containing of the one quantity to the containing of the other ; and
Lect. XXI. LOGIC. 305
because, each quantity necessarily implying the indefinite existence
of the other, we are consequently permitted to render this necessary
implication the ground of a logical inference.
It is manifest, however, in the first place, that such a cross and
hybrid and indirect reasoning from the one
This hybrid infer- quantity to the other, in the fourth figure, ia
ence is, 1. Unnatural. ^ •' ' -, ^
wholly oi a different character and account from
the reasoning in the other three figures, in which all inference,
whether upwards or downwards, is equable and homogeneous
within the same quantity. The latter in short is natural and easy;
the former, unnatural and perverse.
In the second place, the kind of reasoning competent in the fourth
figure is wholly useless. The chanjje from the
2. Useless. . .
one quantity to the other in the course of a syl-
logism is warranted by no necessity, by no expediency. The reason-
ing in each quantity is absolute and complete within itself, and all
that can be accomplished in the one process can equally well be ac-
complished in the other. The jumping, therefore, from extension to
comprehension, or from comprehension to extension, in the conclu-
sion of the fourth figure, is a feat about as reasonable and useful in
Logic, as the jumping from one horse to another would be reason-
able and useful in the race-course. Both are achievements possible ;
but, because possible, neither is, therefore, a legitimate exercise of
skill.
We may, therefore, on the ground that the fourth figure involves
a useless transition from one quantity to another, reject it as a logi-
cal figure, and degrade it to a mere logical caprice.
But, in the third place, there is a better ground ; the inference,
though valid in itself, is logically, is scientifi-
3. Logically invalid. n • t i -n ,i • r- • i i •••
cally, invalid. J^or the inference is only legiti-
mated by the occult conversion of the one quantity into the other,
which takes place in the mental process. There is thus a step taken
in the reasoning which is not overtly expressed. Were the whole
process stated in language, as stated it logically ought to be, instead
of a simple syllogism with one direct conclusion, we should have a
complex reasoning with two conclusions ; one conclusion direct and
immediate (the inference, to wit, of conversion), and from that im-
mediate conclusion another mediate and indirect, but which, as it
stands, appears as the one sole and exclusive conclusion from the
premises. This ground, on which I think the fourth figure ought to
be specially abolished, is stated with the requisite details in the Logi-
cal Appendix contained in the second edition of my Discussions on
Philosophy}
39 1 p. 663. — Ed.
LECTURE XXII.
STOICHEIOI. OOY.
SECTION II.— OF THE PRODUCTS OF THOUGHT
III. — DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO EXTERNAL
FORM.
C. REGULAR AND IRREGULAR.
FIGURE — REDUCTION.
In my last Lecture, after terminating the view of the nineteen
Moods of the Four Syllogistic Figures, accord-
ing to the doctrine of logicians, I entered on the
consideration, — how far their doctrine concerning the number and
legitimacy of these various figures and moods was correct. In the
conduct of this discussion, I proposed, firet, to treat of the Figures,
and, secondly, to treat of the Moods. Commencing, then, with the
Figures, it is manifest that no exception can possibly be taken to
the first, which is, in point of fact, no figure at all, but the one reg-
ular,— the one natural form of ratiocination. The other three fig-
ures divide themselves into two classes. The one of these classes
comprehends the fourth ; the other, the second and third figures.
The fourth figure stands, on the common doctrine of the logicians,
in a more unfavorable situation than the second and third. It was
not recognized by Aristotle ; it obtained admission into the science
at a comparatively recent period ; it has never in fact been univer-
sally recognized ; and its progress is manifestly more perverse, cir-
cuitous, and unnatural, than that of any other.
In regard to this fourth figure, I stated that the controversy among
logicians touching its legitimacy had been without result ; its op-
ponents failing to show that it ought to be rejected ; its defenders
failing to show that it was deserving of recognition. I then stated
that the logicians, in their one-sided view of the reasoning pi'ocess,
I
Lect. XXn. LOGIC. 307
had let slip the one great principle on which the legitimacy of this
jSgure was to be determined, I then explained to you that the pecu-
liarity of the fourth figure consists in this, — that the premises are
apparently the premises of a syllogism in one kind of quantity, while
its conclusion is the converted conclusion of a syllogism in the other.
It is thus in every point of view contorted and preposterous. Its
premises are transposed, and the conclusion follows from these, not
directly, but through the medium of a conversion. I showed how,
and how far, this kind of reasoning was competent, and that though
the inference in the fourth figure is valid, it is inconvenient and use-
less, and therefore, that the form itself, though undoubtedly legiti-
mate, is still only a legitimate monster. Herewith the Lecture ter-
minated.
Now, looking superficially at the matter, it might seem, from what
has now been said, that the fourth ought to be
General character of ^^ q^qq expunged from the series of logical fig-
the Second, Third, and t-» , i • .• mi v
r, _,, ^. ures. But a closer exammation will show us
Fourth Fij»ures.
that this decision would be rash. In point of
fact, all figure properly so called, that is, every figure, with the ex-
ception of the first, must be rejected equally with the fourth, and on
the following ground, — that they do not, in virtue of their own
expressed premises, accomplish their own inference, but that this is
done by the mental interpolation of certain complementary steps,
without which no conclusion in these figures could be drawn. They
.ire thus in fact reasonings apparently simple, but in reality complex ;
and when the whole mental process is expressed, they are found to
be all only syllogisms in the first figure, with certain corollaries of
the different propositions intermingled.* This doctrine corresponds
with that of the logicians, in so far as they, after Aristotle, have
allowed that the last three figures are only valid as reducible to the
first ; and, to accomplish this reduction, they have supplied us with
a multitude of empirical rules, and lavished a world of ingenuity in
rendering the working of these complex rules more easy. From
Whately and the common books on Logic, you
Latin and Greek are of course acquainted with the import of the
mnemonics,-theirau- consonants in the cabalistical verses, Barbara,
thor8. .
Celarent, etc. ; ^ and it must be confessed that,
taking these verses on their own ground, there are few human
inventions which display a higher ingenuity. Their history is ap-
1 This doctrine of Figure, which is devel- Werke, i. p. 55, ed. Rosenkranz and Schubert
oped in paragraph Ixxv., is mainly taken — Ed.
from Kant. See his Essay, Die Falsche Spitz-
findigkeit der vitr Syllogistischen Figuren, 1762. 2 See Discussions, p. 666.— Ed.
308
LOGIC.
Lect. XXH
parently altogether unknown to logicians. They were, in so fer as
they relate to the three first or Aristotelic figures, the invention oi
Petrus Hispanus, who died in 1277, Pope John XXII. (or as he is
reckoned by some the XXI., and by others the XX.). He was a
native of Lisbon. It is curious that the corresponding Greek mne-
monics were, so far as I can discover, the invention of his contem-
porary Nicephorus Blemmidas, who was designated Patriarch of
Constantinople.^ Between them, these two logicians thus divided
the two highest places in the Christian hierarchy ; but as the one
had hardly begun to reign when he was killed by the downfall of
his palace,^ so the other never entered on his ofiice by accepting his
nomination at all. The several works of the Pope and the Patri-
arch were for many centuries the great text-books of Logic, — the
one in the schools of the Greek, the other in the schools of the
Latin church.
The Greek symbols are far less ingenious than the Latin, as they
only mark the consecution, quantity, and quality
The Greek symbols of the different propositions of the Various moods
^ mgenious an e ^^ ^^^ three generally admitted figures, Mithout
showing to what mood of the first the moods of
the other two figures are to be reduced, far less by what particular
process this is to be done. All this is accomplished by the symbols
of the Roman Pontiff". As to the relative originality, or the j^riority
in point of date, of these several inventions, I am unable to speak
with certainty. It is probable, however, that the Blemmidas was
the first, both because his verses are the simpler and ruder, and be-
cause it is not known that he was acquainted with the writings of
the Western logicians : whereas I find that the Summulce of His-
panus are in a great measure taken, not indeed from the treatise of
Blemmidas upon Dialectic, but from the Synopsis of the Organon
of his somewhat earlier contemporary Michael Psellus.'
But the whole of the rules given by logicians for the Reduction
of Syllogisms are unphilosophical, for they are
merely the empirical statements of the opera-
tion of a principle in detail, which principle it-
self has been overlooked, but which, when once
rationally explicated, supersedes the whole com-
plex apparatus of rules for its mechanical application.
If I succeed, therefore, in explaining to you how the last three
The Kulcs of logi-
cians for the Keduction
of Syllogisms unphil-
osophical.
1 Bat see Discussions, p. 672. — Ed.
2 See riatina [Historia de Yitis PonHficutn
Ri)manonim,p. 181, ed. 1572. — Ed].
i The reverse is probabl/ the truer account;
the work which goes by the name of Psellus
being in all probability a translation from His-
panus, the mnemonics, with one exception«
being omitted. See Discussions, p. 128. — Ed
Lfxt. XXII. LOGIC. 809
Figures arc only the mutilated e.vprcssion? of a complex mental
process, I shall not only subvert tlieir existence
The last tliree Fig- „ ' -, . "■ . ,, . , .
, ., ... . , as lorms oi reasoninLT nut \irtuailv nlentical
ures only the mutilated -^
expressions of a coin- witli the first figure. — I shall nut only relie\'e
piex mental proce.-?, you from the necrs>it\- <jf stuilviniT the tediuus
and virtually identical ^^^j dh^usUuiS rule> ' vf tlieir reduction, hut in
with the first. . ' . '-
fiict vindicate the gruat jirinciples of rr:;>uiiing
from apparent anomaly. For, in the lirst place, if the thix'e last fig-
ures are admitted as genuine and original f ;rms of reasuning, the
principle that all reasoning is the recognition of the relation of a
least part to a greatest whole, tlirough a k'Sser whule dv greater
part, is invalidated. For, in the three latter fig'are>. the middle
term does not really hold the relation tif an intermediate wh^le or
part to the sidiject and [iredicate of the conclusion ; fir rilln.r, in
the second figure, it contains them both, iir, in the third, is euiitained
by them lioth, ur. in the fourth, at once contains the greatest whole
(that is, the predicate in extensi\'e, the subjeet in cum]irLdifii>i\-e,
quantity), and is containeil Ijy tlie smallest part (that is, the subject
in extensi\-e. the predicate in co!inii-ehensi\e, cjuantity). In the sec-
ond place, if these three figures are admitted as inde]iende!it and
legitimate lurms, tlie second general ride I ga\e you f u' cateL:()rical
syllogisms is invalidated iu both its clauses. Fur it \vill nut hold
true, that every categorical sylloQ-ivm mu>t lun'e an universal sump-
tion and an afiirmati\-e subsunq.tiun. The h-n\- (4' the univei-sal
quantity of the sumption is violatetl in the third tiii-uye. by ])is;uins
and Bocardo, in the fourth, by Dimari.-: the law tif the afiirina.tive
quality of the subsumption is viulatch in tlie second figure, by C'a-
mestres ami IJaroco ; and. in the fourth, by C'amenes. I, therefore.
proceed to reconcile all these anomalies by the extinction of the
hist three figures, as more than accidental modifications of the lirst,
and commence with the followins: parairraph.
1i LXXV. The three last (that is. Second. Third. Fourth)
Figures are mcrelvhvbrid or mixed reasuii-
Par. LXXV. The • ^ . ,..,'' , ,
Second, Th.rd. and 1"?^' 1" ^^"'i't'^^ ^^>'-"' ^^^'S Ot tllC l-rOCCSS are
Fourth Figures only ouly partially cxprcsscd. The unexpressed
accidental modifica- , ■ i • • x-
^,^ „. , Steps are, m ixencral. conversive mterences.
tions of the First. I ' r-
which we are entitled to make. 1°, From the
absolute negation of a first notion as predicated of a second, to
the absolute negation of the second notion as predicated of tl;j
first — if >iO A /.•* B; thin no B is A: 2°. From the total or
partial affirmation of a lesser class or notion of a greater, to the
partial affirmation of that greater notion of that lesser, — if all
(or soyne) A is B ; then some B is A.
310 LOGIC. Lect. xxn,
Taking the figures and moods in their common order; in the
Second Figure the
Moods of Second , . , , ^ i •
Figure. 1. Cesare. which the formula IS
Second Figure the first mood is Cesare, of
Moods of Second ®
JVbPtsM;
But oZZ S are M;
Therefore, no S is P.
Here the ostensible or expressed sumption, No P is M, is mentally
converted into the real sumption by the inference, — Then no M is
P. The other propositions follow regularly, — viz. :
But aOSare M;
Therefore, no S is P.
In reality Ceiarent. The real syllogism, fully expressed, is thus :
Real SamptioD, .... No M ts P;
Subsumption, But all S are M ;
Ck>nclusion, Ergo, no S is P.
To save time, I shall henceforward state the complementary prop-
ositions which constitute the real and proximate parts of the syl-
logism, by the name of real, proximate, or interpolated sumption,
subsumption, or conclusion ; and those who take notes may simply
mark these, by placing them within brackets. To avoid confusing
the conversive inference with the ostensible conclusion of the syl-
logism, I shall mark the former by the illative conjunction then;
the latter by the illative conjunction therefbre. I shall take the
concrete examples which I chanced to give in illustration of the
various moods. In Cesare the concrete example was :
Ostensible Sumption, Nothing that it material has free will;
Real, Interpolated, Sumption, .... ( Then nothing that has free vnU is material;)
Subsumption, But nil spirits have freewill;
Conclusion, Therefore, no spirit is material.
Throwing out of account the ostensible sumption, and considering
the syllogism, in its real nature, as actually evolved out of the sump-
tion mentally understood ; we have thus, instead of a syllogism in
Cesare of the second figure, a syllogism in Ceiarent of the first.
The seeming irregularity is thus reduced to real order.
The second mood of the second figure, viz. Camestres,^ is rather
1 [That Cesare and Camestres are the same Syllo^., p. Ill, and authorities cited abore, p
(yllogism with accidental order of premises, 296, note.]
see Zabarella, Opera Logiea, Dt Quarto Figura
Lect. XXn. LOGIC. 311
more irregular, and, therefore, the process of redressing it, though
equally easy, is somewhat more complex. The
2. Camestres. formula is :
All T are M.;
ButnoSts'il;
Therefore, no S is P.
Here, in the first place, the premises are transposed, for you re-
member by the second general law of syllogisms,
In reality Celareut. . . • i • i i
the sumption must in extension be universal, and
the subsuraption affirmative. By a preliminary operation, their ap-
parent consecution must, therefore, be accommodated to their real.
The premises being restored to order, there is yet a further intricacy
to unravel. The sumption and the conclusion are neither of them
proximate ; for we depart from a conversive sumption, and primarily
obtain a conclusion which only gives us the ostensible conclusion, in
the second instance, through an inference. Thus :
Ostensible Sumption, iVb S « M ;
Proximate or Real Sumption, . . . ( Then no M. is S;)
Subsumption, AUF are M ;
Proximate or Real Conclusion, . . ( Therefore, no P is S;)
Ostensible Conclusion, Therefore, no S is P.
The concrete example given was :
All colors are visible ;
But no sound is visible ;
Therefore, no sound is a color.
Reveraing the premises, we have :
Apparent Sumption No sound is visible ;
Proximate or Real Sumption, . ( Then nothing visBle is a sovnd;)
Subsumption, All colors are visible ;
Proximate or Real Conclusion, ( Therefore, no color is a sourtd;)
which gives, as a conversive
inference, the
Expressed Conclusion, .... Then no sound is a color.
Thus it is evident that Camestres, in the second figure, is only a
modification of Celarent in the first.^
1 Cf. Krug, Logik, J 109, p. 363. Mark Dun- [Derodon, Logica Restit., Pare. iv. p. 6t8L
can, Instit. LogUce, L. iv. c. 4, p. 229. — Ed. Eeusch, Systema Logicum, i 439, p. 613.]
312 LOGIC. Lkct. XXII
The third mood of the Second Figure, Festino, presents no diffi-
3 Festino. culty. We have only to interpolate the real
sumjDtion, to which the subsumption and conclu-
In reality Ferio. . . ^ , « rm
sion proximately refer. Ihus:
Expressed Samption, . . . JVo P w M ;
Real or Proximate Sumption, ( TTien ttoMisP);
Subsumption, But some S are M;
Conclusion, Therefore, some S are not P.
Our concrete example was :
Expressed Sumption, . . . No vice is laudable ;
Some actions are laudable ;
Therrfort, $ome actions art not vtm.
Here we have only to intci-polate, as the real sumption :
Nothing laudable is a vice.
Festino, in the second figure, is thus only Ferio in the firet, with its
sumption converted.
The fourth mood, Baroco, is more troublesome. In fact, this
mood and Bocardo, in the third figure, have
been at once the cruces and the opprobria of
logicians. They have, indeed, succeeded in reducing these to the
first figure by what is called the reductio ad
^^ "* " jinpos- {mj)ossibile, that is, by circuitously showing that
if you deny the conclusion in these syllogisms,
the contradictory inference is absurd ; but as of two contradictories
one or other must be true, it, therefore, remains that the original
conclusion shall be admitted. This process is awkward and perplex-
ing ; it likewise only constrains assent, but does not .afford knowl-
edge ; while at the same time we have here a syllogism with a neg-
ative subsumption, which, if legitimate, invalidates the universality
of our second general rule. Now, on the principle I have proposed
to you, there is no difficulty whatever in the reduction of this or of
any other mood. Here, however, we do not, as in the other moods
of the second figure, find that the syllogism proximately departs
from an unexpressed sumption, but that the prox-
Tn reality Daril. , , ^ . , , • ,
imate subsumption and the proximate conclu-
sion have been replaced by two derivative propositions. The
formula of Baroco is :
Lkct. XXII. LOGIC. J?ll
AUFareJ/L;
But some S are notM;
Therefore, some S are not P.
But the following is the full mental process :
Sumption, AUP aretl;
Real Snbsumption, {Some not-M. are S;)
which gives the ( TTien, some S are noi-M;
Expressed Subsumption, ( Ov, some S are not ^;
Real Conclusion, ( Therefcyre, some nol-F are S;
which gives the { Tlien, some S are not-P;
( The
(Or,
Expressed Conclusion, ( Or, some S are not P.
Or, to take our concrete example :
All birds are oviparous ;
But some animals are not oviparous ;
There/ore, some animals are not birds.
Of this the explicated process will stand as follows :
Sumption, . All birds are oviparous;
Real subsumption, {Some things not oviparous art, atdrntds;)
which gives the { Then, some animals are not-oviparous ;
Expressed Subsumption, ( Or, are not oviparous ;
_,_,.. ^ , . ( ( Therefore, some things not birds are ani-
Real or Proximate Conclusion, .... J ^ j > •>
, . , . ^, (. mals:)
which gives the '
„ J /^ 1 • ( Then, some animals are not-birds;
Expressed Conclusion, J '
(. Or, are not birds.
Now, in this analysis of the process in Baroco, we not only re>
solve the whole problem in a direct and natural and instructive
way; but we get rid of the exception which Baroco apparently
affords to the general rule, that the subsumption of a categorical
must be affirmative. Here you see how the real subsumption is
affirmative, and how, from having a negative determination in its
SMbject, it by conversion assumes the appearance of a negative pro]>-
osition, the affirmative proposition — some things not-birds are ani-
mals, being legitimately converted, first into — some animals are
no^-Wrc?5, and this again being legitimately converted into — some
animals are not birds. You recollect that, in the doctrine of Prop-
ositions,^ I showed you how every affimiative proposition could be
adequately expressed in a negative, and every negative in an affir-
m*ative form ; and the utility of that observation you now see, as it
1 See above, p. 178. — Ed.
40
314
LOGIC,
Lect. XXU
Third Figure.
enables us simply to solve the problem of the reduction of Baroco,
and, as we shall also see, of Bocardo. Baroco is thus directly re-
duced to Darii of the first figure, and not, as by the indirect process
of logicians in general, to Barbara.^ On this doctrine the name
Baroco is also improper, and another, expressive of its genuine
affinity, should be imposed.
We proceed now to the Third Figure. You will observe that,
as in the Second Figure, with the exception of
Baroco, it was the sumption of the two premises
which was affected by the conversion, so in the third it is the sub-
sumption. For in Camestres of the second, and in Disamis and
Bocardo of the third, figure, the premises are transposed. This
understood subsumption is a conversive inference from the expressed
one, and it is the proxininte antecedent from which the real con-
clusion is immediately inferred.
In the first mood of this figure, Darapti, the subsumption is a
1. Darapti. universal affirmative ; its convei-sion is, therefore,
In reality Darii. into a particular affirmative. Its formula is —
Sumption, AUMareF;
Expressed Subsumption, . . . Bui all IS. are S;
which {^ives the
Really Proximate Subsumption, . ( Then some S are M;)
from which directly flows
The Conclusion Therefore, tome S are P.
1 There seems to be an error in the text
here. The syllogism, as finally reduced, is
not in Darii, nor in any legitimate mood ;
and its natural reduction, according to the
method adopted by the Author, is not to Da-
rii, but to Ferio, by means of an unexpressed
sumption. Thus —
AttTcBreJA;
Then no no/-M are P;
Some S are noNM;
Ther^ore, some S are not P.
This is the method adopted by the following
logicians, referred to by the Author in his
Common-Place Book, viz. : — Noldius, who
calls Baroco, Facrono, Logica Recognita, cap.
xii. } 12, p. 300, 1666; Reusch (who follows
Noldius), Systema Logicum, § 631). p. 611. 2d
ed.,1741; Wolf, Phil. Rationalis, } 384; Bach-
mann, Logik, § 133, Anni., i. p. 224. Before
any of the above-mentioned writers, Mark
Duncan gives the reduction of Camestres to
<.'elnri-nt, and of Baroco to Fcrio, by coun-
terjiosition. He adds, with special reference
to the reduction of Baroco to Ferio by this
method, — " Hanc reductionis speciem exist-
imo a scholasticis perspectam Aiisse: sed de.<>.
pcctam; quia in prima figura propositio mi-
nor aflirmans attributi iniiniti, quam primo
intuitu videatur esse negans, formx eviden-
tiam obscurat: atqui syllogismorum reductio
comparata est non ad formse bonitatem ob-
scurandam, sed illustraiidam." InUitutionei
Logica, L. ir. c. 3, S 4, p. 230. Salmurii, 1612
The syllogism of the text may also be ex-
hibited morecircuitously.as Darii, by retain-
ing the affirmative quality in the converted
proposition. Thus ; —
\
An not-il are not-P;
Some S are not Ml
Ther^ore, tome 8 cart iio^P.
This is the method of reduction employed
by Derodon, who, in the same way, would
reduce Camestres to Barbara, Logica Restituia,
P. iv. tract, i. c 2, art. 6, p. 648. The error
here noticed seems to have originated in a
momentary confusion of the reduction of
Baroco with that of Bocardo; which, hoV-
ever, could not be rectified without greater
alterations in the text than the Editors con-
sider tliemselves Justified in making —Ed
Lect. XXn. LOGIC. 315
Our concrete example was —
Sumption, All gilding is metallic ;
Expressed Subsiimption, Bui all <jildin<j shines;
which jiivcs, as a conversion, the
Real Subsuniption, 7'hen, some things that shine are (jilding ;
and from this last immediately pro-
ceeds the
Conclusion, Therefore, some things that shine are vietaliic.
Thus Darapti, in the third figure, is nothing but a one-sided
derivative of Darii in the first.'
The second mood of the Tliird Figure is Fe-
2. Felapton. , t i-- i
lapton. Its lormula —
Sumption, No M i's 1';
Expressed Sinni)ti(jn 1// M areS;
The Ileal Subsuniption, . . . {Thtn, some S are "^l;)
from which
The Conclusion, Therefore, some S are not P.
Our example was —
Sumption, Nothing material is a free acjcnt;
Expressed Subsumption, But eceryfhing material is extended;
Of which the Real Subsumption is the ) , ^, , . , , . . , ,
r ( Iken, something extended is material;)
converse, >
^ Therefore, something extended is not a free
From which the Conclusion, -;
( agent.
Felapton, in the third Figure, is thus only a modification of Ferio
in the first.
The third mood in this figure is Disamis. Its
3. Disamis. ^ ,
lormula —
Some M are P;
But all M are S;
Therefore, some S are P.
Here the premises are transposed. Their or-
In reality Darii. t i • -r. -,
der bemg rectified :
Sumption, AlllslareS;
Expressed Subsumption But some 'M are P ;
1 [Eeusch, Systema Logicum, § 539, p. 614.]
316 LOGIC. ' Lect. XXII.
Which, by conversive inference, gives the ^
T. . . c w ^- f ( I'hen, some P are M;)
Proximate Subsumption, )
From which proceeds the Real Conclusion, (Therefore, tome V are &;)
Whichfby conversion, gives the Expressed >
„ , . y Then, some S are P.
Conclusion, ) '
Our example was (the reversal of the premises being rectified) :
Samption, All acts of homicide are cruel;
Expressed Subsumption, But some acts of homicide are laudable ;
Which {fives, as a conversive inference, 7 ( Then, some laudable acts art acts of homi-
the Proximate Subsumption, . . .) cide;)
From this Proximate Conclusion, . . . ( Therefore, some laudable acts are cruel;)
Which ainiin gives, as its converse, the ) _, , , , , , .
>- Therefore, some cruel acts are laudable.
Expressed Conclusion, >
Thus Disamis in the third is only Darii in the first figure.
The fourth mood of the Third Figure is Datisi, which is only
Disamis, the premises not being revereed, and
- ,., r^ ,. the conclusion not a conversive inference. It
In reality Darii.
requires, therefore, only to interpolate the prox-
imate subsumption. Thus:
Sumption, -iWMnreP;
Expressed Subsumption, But some "M. are S;
Giving by conversion, {TTien, some S are }ti;)
From which last the Conclusion, . . . Therefore, some S are P.
Sumption, All acts of homicide are erue* ,
Expressed Subsumption, But some acts of homicide are laudable;
Which gives, by conversion, the Proxi- ) ( TTien, tome laudable acts are acta of homi-
mate Subsumption, > cide;)
From which the Conclusion, Therefore, tome laudable acts are crueL
Thus, Datisi likewise is only a distorted Darii.
The fifth mood of the Third Figure is the famous mood Bocardo,
which, as I have mentioned, with Baroco, but
far more than Baroco, was the opprobrium of
the scholastic system of reduction. So intricate, in fact, was this
mood considered, that it was looked upon as a trap, into which if
you once got, it was no easy matter to find an exit. Bocardo was,
during the middle ages, the name given in Oxford to the Academi-
cal Jail or Career — a name which still remains as a rolique of the
ancient logical glory of that venerable seminary. Rejecting, then.
Lect. XXn. LOGIC. 317
the perplexed and unsatisfactory reduction by the logicians of Bo-
cardo to Barbara by an apagogical exposition, I commence by stat-
ing, that Bocardo is only Disamis under the form of a negative
affirmative ; its premises, therefore, are transposed. Removing the
transposition, its formula is —
All M are S ;
But some M are not P ;
Therejbre, some S are nofP;
which is thus explicated, like Baroco —
Sumption, AUilareS;
Expressed Subsumption, Some M are tiof P;
Which gives, by conversive inference, . (Then, some noi-V are ilL;)
From this Real Subsumption proceeds the )
Proximate Conclusion,
Which again
Expressed
Whence again, Some S are not P;
>• ( There/ore, some not-P are S;)
iin gives, by conversion, the ) ^ „ _
y Then, some S are not-P ;
ised Conclusion, )
Our concrete example was — the order of the premises being
redressed ;
Sumption, All syllogisms are important ;
Expressed Subsumption, But some syllogisms are not regttlar ;
\ ( Then, some things not regular are syllo-
From which, by conversive inference. .
1. gisms;)
And from this Proximate Subsumption ) Therefore, some things not regular are im-
proceeds the Proximate Conclusion, . J poriant ;
From whence, by conversion, the Ex- )
, „ , . f Then, some important things are not-regular <
pressed Conclusion, >
^,^ J Whence, some important things are not regit-
(. lar.
Bocardo is thus only a perverted and perplexed Darii.^
The last mood of the Third Figure is Ferison,
In reality Ferio whicli is without difficulty — it Only being re-
quired to interpolate the real subsumption, from
which the conclusion is derived. Its formula is —
Sumption, iVo MwP;
Expressed Subsumption, But some M are S ;
1 (See Noldins, Log. Rec. c. xii. ) 12, p. 301. Bocardo is called Docamroc by Koldius. Cf
Reusch, Syst. Log., i 539, p. 611.]
818 LOGIC. Lect. xxn
Which gives, by conversive inference, the ")
r Then, some S are M; •
Subsumption j
From which immediately flows the Con-}
> Therefore,
, _,_.., some S are ikX P.
elusion,
Snmption, No truth, is without resuU ;
Expressed Sabsnmption, But some truths are misunderstood;
The Conversive Inference from which is, ITien some things misunderstood are truths ;
And from this Implied Subsumption im- > There/ore, some things misunderstood are not
im- >
» • f
mediately proceeds the Conclusion, . ) tdthout result.
Ferison ^ is thus only Ferio, jfringed with an
Fourth Figure. • t . /.
accident oi conversion.
The Fourth Figure is distinguished from the two former in this
— that in the Second and Third Figures one or other, but only one
or other, of the premises requires the interpolation of the mental
inference ; whereas, in the Fourth Figure, either both the premises
require this, or neither, but only the conclusion. The three first
moods (Bamalip, Calemes, Dimatis) need no conversion of the prem-
ises ; the two last, Fesapo and Fresison, require the conversion
of both.
The result of the foregoing discussion is thus accordingly that, in
rigid truth, there is no figure entitled to the dig-
The First Figure the nity of a simple and independent form of rea-
onysimpe an in e- goning, cxccpt that which has improperly been
pendent form of rea- i i -r^. r r ^
goning. termed the First ; the three latter figures being
only imperfect or elliptical expressions of a com-
plex process of inference, which, when fully enounced, is manifestly
only a reasoning in the first figure. There is thus but one figure,
or, more properly, but one process of categorical reasoning; for the
term figure is abusively applied to that which is of a character reg-
ular, simple, and essential.
Having, therefore, concluded the treatment of figure in respect
of Categorical Syllogisms, it remains to con-
Figure of Hypcthet- sidcr how far the other species of Simple Syllo-
icai, Disjunctive, and -^^ _ ^^^ hypothetical, the disjunctive, and
Hypotlietico-Disjunct- ° ... . . '.
ive Syllogisms ^^^ hypothetico-disjunctive — are subject to this
accident of form. In regard to the Hypothetical
Syllogism, this kind of reasoning is not liable to the affection of
figure. It is true indeed that we may construct a syllogism of three
hypothetical propositions, which shall be susceptible of all the fig-
1 [Scotus says that Ferison, Bocardo, and Felapton, are useless, as concluding indirectly
QuantionfS, In Anal. Prior.y L. i. q. 24.]
Lkct. XXII. LOGIC. 319
ures incident to a categorical reasoning ; but this is itself in fact
only a categorical syllogism hypothetically expressed. For example :
If K is, then B is;
But if S is, then Ais ;
Therefore, if S is, then B ts.
This syllogism may certainly be varied through all the figures,
but it is not an hypothetical syllogism, in the proper signification
of the term, but manifestly only a categorical ; and those logicians
who have hence concluded, that a hypothetical reasoning was ex-
posed to the schematic modifications of the categorical, have only
shown that they did not know how to discriminate these two forms
by their essential diflfcrences.
In regard to the Disjunctive Syllogism the case is different; for
as the disjunctive judgment is in one point of view only a categor-
ical judgment, whose predicate consists of logically opposing mem-
bers, it is certainly true that we can draw a disjunctive syllogism
in all the four figures.
I shall use the letters P, M, and S ; but as the disjunction requires
at least one additional letter, I shall, where that is necessary, take
the one immediately following.
Figure I.
M ts either P or Q ;
* StsM;
Therefore, S is either P or Q.
Figure II.
First case —
P is either M or N;
S is neither M nor N;
Therefore, S is not P. .
Second case —
P is neither M nor Nj
S is either M or N;
Therefore, S is not P.
Figure HI.
M is either P or Q ;
MtsS;
Therefore, some S is either P or Q.
^20 LOGIC. Lect. xxa
FionRE rv.
First case —
P is eiUier M or N;
Both M. and E are 8;
Therefore, some S uP.
Second case —
P is either M or N;
Neither M nor N i« S;
Therefore, S is not P.*
Of Composite Syllogisms — I need say nothing concerning the
Epicheirema, which, it is manifest, may be in
jgnreo omposi e ^^^ figure equally as another. But it is less evi-
Syllogisms. ° .
dent that the Sorites may be of any figure; and
logicians seem, in fact, from their definitions, to have only contem-
])lated its possibility in the first figure. It is, however, capable of
all the four schematic accidents by a little contortion ; but as this
at best constitutes only a logical curiosity, it is needless to spend
any time in its demonstration."^
So much for the Form of reasoning, both Essential and Acci
dental, and the Divisions of Syllogisms which are founded thereon.
1 See Chr. J. Braniss, Grundruw der Log-it, } difiTerent figures, see Uerbart, Lehrbueh zur
394, p. 146. Compare Knig,Logiit, p. 387 e/ if?. Einleitung in die Philosophie, i 70. Drobisch,
2 For a complicated theory of Sorites in Neue Darstellung der Logik, }{ 80 — 84. — Eo.
LECTURE XXIII.
STOICHEIOLOGY.
SECTION II.— OF THE PRODUCTS OF THOUGHT.
III. — DOCTRINE OF REASONINGS.
SYLLOGISMS. — THEIR DIVISIONS ACCORDING TO VALIDITY.
FALLACIES.
All the varieties of Syllogism, whose necessary laws and oontirr-
pfent modifications we have hitherto considered, are, taken together,
divided into classes by reference to their Validity ; and I shall com-
prise the heads of what I shall afterwards illustrate, in the follow-
ing paragraph.
% LXXVI. Syllogisms, by another distribution, are distin-
guished, by respect to their Validity, into
Par. LXXVI. syuo- Corvect ov True, and Incorrect or False.
glsms, — Correct and mi t tt i • ^ i i
Incorrect. I he lucorrcct or liaise are agam (though
not in a logical point of view) divided, by
reference to the intention of the reasoner, into Paralogisms,
Faulty, and into Sophisms, or Deceptive, Reasonings. The
Paralogism {paralogisnius) is properly a syllogism of whose
falsehood the employer is not himself conscious; the Sophism.
{sophisma, captio, cavillatio) is properly a false syllogism, fab-
ricated and employed for the purpose of deceiving others.
The term ^aZ^acy may be applied indifferently in either sense.
These distinctions are, however, frequently confounded ; nor in
a logical relation are they of account. False Syllogisms are,
again, vicious, either in respect of their form or of their matter,,
or in respect of both form and matter.*
1 Krug, Logik, J 115.— Ed.
41
^22 LOGIC. ' Lect. XXlli
In regard to the first distinction contained in this paragraph, —
of Syllogisms into Con-ect or True and Incor-
Explication. rector False, — it is requisite to say a few words.
iut^'Trulh ""discrimt ^^ '^^ nccessary to distinguish logical truth, that is,
nated. the truth which Logic guarantees in a reasoning,
from the absolute truth of the several -judgments
of which a reasoning is composed. I have frequently inculcated on
you that Logic does not w}»aTant the truth of its premises, except
in so far as these may be the formal conclusions of anterior reason-
ings,— it only warrants (on the hypothesis that the premises are
truly assumed) the truth of the inference. In this view the conclu-
sion may, as a separate proposition, be true, but if this truth be not
a necessary consequence from the premises, it is a false conclusion,
that is, in fact, no conclusion at all. Now, on this point there is a
<loctrine prevalent among logicians, which is not only erroneous,
but, if admitted, is subversive of the distinction of Logic as a
purely formal science. The doctrine in question is in its result this,
— th^nt if the conclusion of a syllogism bo true, the pi'emises may
be either true or false, but that if the conclusion be false, one or
both of the premises must be false ; in other woi'ds, that it is possi-
ble to infer true from false, but not false from true. As an example
of this I have seen given the following syllogism ; *
Aristotle is a Ronum ;
A Roman is a European ;
Therefore, Aristotle is a European-
The inference, in so far as expressed, is true ; but I would remark
that the whole inference which the premises necessitate, and which
the conclusion, therefore, virtually contains, is not true, — is false.
For the premises of the preceding syllogism gave not only the
conclusion, Aristotle is a European^ but also the conclusion, Aris-
totle is not a Greek; for it not merely follows from the premises
that Aristotle is conceived under the universal notion of which the
concept Roman forms a particular spliere, but likewise that he is
conceived as excluded from all the other particular spheres which
are contained under thr.t univereal notion. The consideration of
the truth of the premise, Aristotle is a Jioman^ is, however, more
properly to be regarded as extralogical ; but if so, then the consid-
eration of the conclusion, Aristotle is a European, on any other
view than a mere formal inference from certain given antecedents,
is, likewise, extralogical. Logic is only concerned with the formal
truth — the technical validity — of its syllogisms, and anything
I
Lect. XXm. LOGIC. 823
beyond the legitimacy of the consequence it draws from certain
hypothetical antecedents, it does not profess to vindicate. Logic:;!
truth and falsehood are thus contained in the correctness and
incorrectness of logical inference ; and it was, therefore, with no
impropriety that we made a true or correct, and a false or incorrect
syllogism convertible expressions.^
In regard to the distinction of Incorrect Syllogisms into Paralo-
gisms and Sophisms, nothing need be said.
The distinction of —.u ^ ^ ^ • ix; • ^i -c ^
Incorrect Syllogisms ^^^ "^^''^ Statement IS Sufficiently manifest;
into Paralogisms and and, at the same time, it is not of a logical
Sophisms, not ofiogi- import. For logic does not regard the inten-
*^ '™P<"" • tion with which reasonings are employed, but
considers exclusively their internal legitimacy. But while the dis-
tinction is one, in other respects, proper to be noticed, it must be
owned that it is not altogether without a logical value. For it
behooves us to discriminate those artificial sophisms, the criticism
of which requires a certain acquaintance with logical forms, and
which, as a play of ingenuity and an exercise of acuteness, are not
without their interest, from those paralogisms which, though not so
artificial, are on that account only the more frequent causes of error
and delusion.
The last distinction is, however, logically more important, viz., 1°,
Of reasonings into such as are materially falla-
Formal and material . i • i i i -i • f ^ '
Fallacies cious, that IS, through the object-matter or their
t propositions ; 2°, Into such as are formally falla-
cious, that is, through the manner or form in which these proposi-
tions are connected ; and, 3°, Into such as are at once materially and
formally fallacious. Material Fallacies lie beyond the jurisdiction
of Logic. Formal Fallacies can only be judged of by an a2:)plica-
tion of those rules, in the exposition of which we have hitherto
been engaged.
The application of these rules will afford the opportunity of ad-
ducing and resolving some of the more capital
Ancient Greek So- j.> ^u o t,* i • i, ^.i- • • • ^
jj. oi those Sophisms, Avhich owe their origin to
the ingenuity of the ancient Greeks. "Many
of these sophisms appear to us in the light of a mere play of wit
and acuteness, and we are left to marvel at the interest which they
originally excited, — at the celebrity which they obtained, and at
the importance attached to them by some of the most distinguished
thinkers of antiquity. The marvel will, however, be in some degree
abated, if we take the following circumstances into consideration.
1 Cf. Esser, Logik, i 109. — £d.
824 LOGIC. Lkct. xxiil
"In the first place, in the earlier ages of Greece, the method of
science was in its infancy, and the laws of thought were not yet
investigated with the accuracy and minuteness requisite to render
the detection of these fallacies a very easy matter. Howbeit, there-
fore, men had an obscure consciousness of their fallacy, they could
not at once point out the place in which the error lay; they were
thus taken aback, confounded, and constrained to silence.
"In the second place, the treatment of scientific subjects was
more oral and social than M'ith us; and the form of instruction
principally that of dialogue and conversation. In antiquity, men
did not isolate themselves so much in the retirement of their
homes ; and they read far less than is now necessary in the mod-
ern world ; consequently, with those who had a taste for science,
the necessity of social communication was greater and more urgent.
In their converse on matters of scientific interest, acuteness and
profundity were, perhaps, less conducive to distinction than vivac-
ity, wit, dexterity in questioning, and in the discovery of objec-
tions, self-possession, and a confident and uncompromising defence
of bold, half-ti'ue, or even erroneous assertions. Through such
means, a very superficial intellect can frequently, even with us,
puzzle and put to silence another far acuter and more profound.
But, among the Greeks, the Sophists and Megaric philosophers were
accomplished masters in these arts.
" In the third place, as we know from Aristotle and Diogenes
Laertius,^ it was the rule in their didlogical disputations, that every
question behooved to be answered by a yes or a no, and thus the
interrogator had it in his power to constrain his adversary always
to move in a foreseen, and, consequently, a determinate direction.
Thus the Sophisms were somewhat similar to a game of forfeits, or
like the passes of a conjurer, which amuse and astonish for a little,
but the marvel of which vanishes the moment we understand the
principle on which they are performed." ^
As the various fallacies arise from secret violation of the logical
laws by which the different classes of syllogisms are governed, and
as syllogisms arc Categorical, or Hypothetical, or Disjunctive, or
Hypothetico-disjunctive, we may pi'operly consider Fallacies under
these four heads, and as transgressions of the syllogistic laws \n
their special application to these several kinds of syllogism.
^ LXXVII. The Syllogistic Laws determine, in reference to
all the classes of Syllogism, the three following principles ; and
I Arist. Soph. Elench., c. 17. Laertius, L. ii. c. 18, i 135. Tlie references are giren bjr Bacb-
mann. — Ed. 2 Baohmann, Logik, i 884, p. 613.
I
Lecx XXIII. LOGIC. 826
all Fallacies are violations of one or other of these principles,
in relation to one or other class of syllogism.
I. If both the Looical Form and the Mat-
Par. liXXVII. Palla- _ ^
oies, -their division tcr of a syllogism bc correct, then is the
andclassifleation. Conclusion trUC.
II. If the syllogism be Materially Correct, but Formally In-
correct, then the Conclusion is not (or only accidentally) true.
III. If the syllogism be Formally Correct, but Materially
Incorrect, then the Conclusion is not (or only accidentally)
true.
Fallacies, as violations of these principles in more immediate
reference to one or other of the Four Classes of Syllogism,
must again be vicious in reference either to the form, or to the
matter, or to both the form and matter of a syllogism. Falla-
cies are thus again divided into Formal and Material^ under
which classes we shall primarily arrange them.
% LXXVIII. Of Formal Fallacies, the Categorical are the
Par Lxxviii For- "^ost frcqucnt, and of these, those whose
mai Paiiaeiea Gate- vicc lies in having four in place of three
goncai. terms {quaternione termino'rum.) ; for this,
in consequence of the ambiguity of its expression, does not
immediately betray itself. Under this genus are comprised
three species, which are severally known under the names of,
1°, Fallacia sensus compositi et divisi ; 2°, Fallacia a dicto
secundum quid ad dictum sim,pliciter, et vice versa / 3°, Fallct-
ciafigurce. dictionis.
"- That in a categorical syllogism only three terms are admissible,
„ ,. . has been already shown, A categorical syllo-
Explication. _ . .
Fallacies arising gism, Avith four Capital notions, has no connec-
from a Quaternio Ter- tion ; and is Called, by way of jest, the logical
"""""""■ quaUruped {animal quadrupes logicum). This
vice usually occurs when the notions are in reality different, but
when their difference is cloaked by the verbal identity of the terms;
for, otherwise, it would be too transparent to deceive either the
reasoner himself or any one else. This vice, may, however, be of
various kinds, and of these there are, as stated, three principal
epecics."
" The first is the Fallacia sensus compositi et divisi, — the Fal-
lacy of Composition and Division} This arises when, in the same
1 [See Fonseca, Instit. Dial., L. viii. c. v. p. 106, Ingolstadii, 1604-]
32« LOGIC. Lect. XXIH
syllogism, we employ words now collectively, now distributively,
so that what is true in connection, we infer must
i.FaUactasensuseom- ^^ ^-^^^ tr\ie in Separation, and vice versa; as, for
ponti et divisi. . x> • • t
example: — All must sin/ Cams sins; there-
fore^ Caius must sin."^ Here we. argue, from the unavoidable lia-
bility in man to sin, that this particular sin is necessary, and for
this individual sinner. " This fallacy may arise
^^Modes of this Fai- -^^ different ways. F, It may arise when the
predicate is joined with the subject in a simple
and in a modal relation, for example : White can be (i. e. become)
Uack, therefore white can be black. 2°, It may arise from the con-
fusion of a copulative and disjunctive combination. T^ius 9 co)i-
ststs or is m,acle up q/* 7 -{- 2, which are odd and even numbers,
therefore 9 is odd and even. 3°, It may arise, if words connected
in the premises are disjoined in the conclusion. Thus : Socrates is
dead, therefore Socrates is" ^
An exam2)le of the first of these contingencies — that which is
the most frequent and dangerous — occurs when, from its univer-
sality, a proposition must be interpi-eted with restriction. Thus,
when our Saviour says, — The blind shall see, — The deof shall hear,
— he does not mean that the blind, as blind, shall see, — that the
deaf, as deaf, shall hear, but only that those who had been blind
and deaf should recover the use of these senses. To argue the
opposite would be to incur the fallacy in question.
The second fallacy is that A dicto secundum quid ad dictum sim-
pliciter, and its converse, A dicto simpliciter ad
2. FaUacia a dicto x- dictum secundum quid. The former of these
urn qui a letum — ^j^^ fallacy A dicto secundum, quid ad dictum
umplicitrr^ and its con- "^ . ■ ■*
ygtBb. simpliciter — arises when, from what is tnie
only under certain modifications and relations,
we infer it to be true absolutely. Thus, if, from the fact that some
Catholics hold the infallibility of the Pope, we should conclude
that the infallibility of the Pope is a tenet *of the Catholic Church
in general. The latter — the fallacy a dicto simpliciter ad dictum
secundum quid — is the opposite sophism, where from what is true
absolutely we conclude what is true only in cei-tain modifications
and relations, as, for example, when from the premise that Man is a
I Krug, Logik, S 116, p. 420. — Ed. [On the Alrarez, in Gale, Pkilosophia Generalis, L. iii
distinction of Scnsus Compositi ft Divisi, so C. iii. sect. 2, } 8, p. 468.]
famous in the question of foreknowledge and
liberty, see its history in Kuiz, Conimtnt'irii 3 [Denzin-^r,] [Die Logik als Wisienschnft
ae Disfiututiones, de Scientia, de Ideis, dt Yeri- dtr Denkkmut, dargestellt, i 558, Bamberg, 183&
late, ae de Vita Dei, Disp. xxxiii. p. 261 et ug. — Ed.]
Lbct. xxni. LOGIC. 32T
Kmng organism^ we infer that A painted or sculptured man is a
living organism}
The third fallacy — the Sophisma Jigurm dictionis — arises when
we merely play with the ambiguity of a word. The well-known
syllogism, 3fus syllaba est ; Mus caseum rodit/ Ergo^ syllaba ca-
seum rodit^ is an example ; or,
Herod is a fox;
A fox is a quadruped ;
Therefore, Herod is a quadruped.
To this fallacy may be reduced what are called the Sophisma equtv-
ocationis, the Sophisma amphibolice, and the Sophisma accentus*
which are only contemptible modifications of this contemptible
fallacy.
^ LXXIX. Of Material Fallacies, those are of the most fre-
quent occurrence, where, from a premise
_^f ^' ^,^'^^^' ^^^^' which is not in reality universal, we con-
rial Fallacies. ^ . .
elude universally ; or from a notion which
is not in reality a middle term, we infer a conclusion. Under
this genus there are various species of fallacies, of which the
most remarkable are, 1°, the Sophisma cum hoc (vel post hoc)^
ergo propter hoc ; 2°, Sophisma pigrum^ or ignava ratio ; 3°>
Sophisma polyzeteseos ; and 4°, Sophisma heterozeteseos*
In this paragraph you will observe that there are given two
genera of Material Fallacies, — those of an Un-
Expiication. YGTiX Universality (sophismata Jictce universali-
<a a les o an n- fatis), and thosc of an Illusive Reason (sophis-
real Universality, and ' \ l
of an Illusive Keason. mata falsi medH, — or 7i07i caiisce ut causce). 1
must first explain the nature of these, consid-
ered apart, then show that they both fall together, the one being
only the categorical, the othel- only the hypothetical, expression of
the same vice ; and, finally, consider the various species into which
the generic fallacy is subdivided.
" Our decisions concerning individual objects, in so far as they
belong to certain classes, are very frequently
1. Of an Unreal fallacies of the former kind ; that is, conclu-
Universality. ' . .
sions from premises of an unreal universality.
For example : — The Jews are rogues, — The Carthaginians, faith-
1 Cf. Denzinger, iMgik, } 564. —Ed. S On these fallacies, see Denzinger, Logik,
H 559, 560, 561. — Ed.
2 Seneca, !>«< , 48. — B». 4 Ct Krug, hog}k^ } 117. — Ep,
328 LOGIC. Lect. XXll!
less, — The Cretans, liars, — The French, hragadocios, — TJie Ger-
mans, iny sties, — The rich, purse-proud, — The noble, haughty, —
Women, frivolous, — The learned, pedants. — These and similar
judgments, which in general are true only of many, — at best only
of the majority, of the subjects of a class, often constitute, how-
ever, the grounds of the opinions we form of individuals ;' so that
these opinions, with their grounds, when expressed as conclusion-
and premises, are nothing else than fallacies of an unreal generality,
— sophisrnata fictce universalitatis. It is impossible, however, to
decide by logical rales whether a proposition, such as those above
stated, is or is not universally valid ; in this, experience alone can
instruct us. Logic requires only, in general, that every sumption
should be universally valid, and leaves it to the several sciences to
pronounce whether this or that particular sumption does or does
not fulfil this indispensable condition." ' The sophisma fictoe uni-
versalitatis is thus a fallacious syllogism of the class of categoricals.
But the second kind of material fallacies, the sophisms of Unreal
Middle, are not less frequent than those of
2. Of Unreal Middle. , . ,. ,„, „ i -. •
unreal universality. When, for example, it is
argued (as was done by ancient philosophers) that the magnet is
animated, because it moves another body, or that the stars arc
animated, because they move themselves; — here there is assumed
not a true, but merely an apparent, reason ; there is, consequently,
no real mediation, and the sophisma falsi medii is committed.
F'or, in these cases, the conclusion in the one depends on the
sumption, — If a body moves another body, it is animated; in
the other, on the sumption, — If a body m,oves itself, it is ani-
mated/hut as the antecedent and consequent in neither of these
sumptions are really connected as reason and consequent, — or as
cause and effect, — there is, therefore, no valid inference of the
conclusion.^ The sophisma non causes ut caiiscB
The fallacies of Un- jg t^u^ an hypothetical syllogism ; but, as it may
real Reason and of i . • n i .^i,* .£» ii r- i
, ,, . ,., be categorically enounced, this fallacy of unreal
Unreal Uuiversahty 9 j ' j ^
coincide. reason will coincide with the categorical fal-
lacy of unreal universality. Thus, the second
example above alleged :
If (he Stan move themsdves, they are animated',
But the stars do move themselves ;
Therefore, the stars are animated : —
is thus expressed by a categorical equivalent —
1 Krug, Logik, i 117. Anm., p. 422. — Ed. « Cf. Krug, Logik, p. 423. — Elk
Lkct. xxiii. logic. 329
All bodi.es that move themselves are animated;
But the stars move themselves ;
Therefore, the stars are animated.
In the one case, the sumption ostensibly contains the subsumption
and conclusion, as the correhitive parts of a causal whole ; in the
other, as the correlative parts of an extensive whole, or, had the
categorical syllogism been so cast, of an intensive whole. The two
genera of sophisms may, therefore, it is evident, be considered as
one, — taking, however, in their particular manifestation, either a
categorical or an hypothetical form.
I may notice that the sophism of Unreal Generality, or Unreal
Reason, isTiardly more dangerous in its positive
Fallacy of Unreal than in its negative relation. For we are not
Keason as dangerous ^^^^.^ disposed" lightly to assume as absolutely
ill its negative as in its . . . , . , .
positive form universal what IS universal m relation to our
experience, than lightly to deny as real what
comes as an exception to our factitious general law. Thus it is
that men having once generalized their knowledge into a compact
system of laws, are found uniformly to deny the reality of all phe-
nomena which cannot be comprehended under these. They not
only pronounce the laws they have generalized as veritable laws
of nature, which, haply, they may be, but they pronounce that
there are no higher laws; so that all which does not at once find
its place within their systems, they scout, without examination, as
visionary and fictitious. So much for this ground of fallacy in gen-
eral ; we now proceed to the species.
Now, as unreal reasons may be conceived infinite in number, the
minor species of this class of sophisms cannot
Species of the fai- y^^ enumerated; I shall, therefore, only take
lacy of Unreal Reason. ' ^
notice of the more remarkable, and which, in
consequence of their greater notoriety, have been honored with
distinctive appellations.
Of these, the first is the Sophisma cum, hoc {vel post hoc), errjo
propter hoc. This fallacy arises when, from the
(■a.) Sophisma cum hoc contingent consecution of certain phenomena in
(vel post hoc), ergo prop- ^ • /> xu • ... i j A
t^i^^g the order oi time, we inter their mutual depend-
ence as cause and effect. When, for example,
among the ancient Romans, a general, without carefully consulting
the augurs, engaged the enemy, and suffered a defeat, it was in-
ferred that the cause of the disaster was the unfavorable character
of the auspices. In like manner, to this sophism belongs the con-
clusion, so long • prevalent in the world, that the appearance of a
42
830 LOGIC. ^ Lect. XXUI
comet was the harbinger of famine, pestilence and war. In fact,
the greater number of the hypotheses which constitute the history
of physics and philosophy, are only so many examples of this fal-
lacy. But no science has exhibited, and exhibits, so many flagrant
instances of the sophism cum hoc, ergo propter hoc, as that of med-
icine ; for, in proportion as the connection of cause and efiect is
peculiarly obscure in physic, physicians have only been the bolder
in assuming that the recoveries which followed after their doses,
were not concomitants, but effects. This sophism is, in practice, of
great influence and very frequent occurrence ; it is, however, in tlie-
ory, too perspicuous to require illustration.
The second fallacy is that which has obtained the npime o^Ignava ra-
tio, or Sophisma pigrum., — in Greek, dpyos Aoyos.^
ignata a lo. ^j^^ excogitation of this argument is commonly
attributed to the Stoics, by whom it was employed as subsidiary to
their doctrine of fate. "It is an argument by which a man endeav-
ors to vindicate his inactivity in some particu-
lar relation, by the necessity of the conse-
quence. It is an hypothetico -disjunctive syllogism, and, when fully
expressed, is as follows :
Sumption. ...... If I ought to exert myself to effect a certain event, this event either must
take place or it must not ;
Snbsumptlon . ... If it must take place, my exertion is superfluous; if it inust not take
place, my exertion is of no avail ;
Ck>nclasion Therefore, on either alternative, my exertion is useless." 2
Cicero, in tjie twelfth chapter of his book, De Fato, thus states it :
If it be fated that you recover from your present disease, whether you call in a doctor or not,
you will recover ; again, if it be fated that you do not recover from your present dis-
ease, whether you caM in a doctor or not, you will not recover;
But one or other of the contradictories is fated;
Therefore, to call in a doctor is of no consequence.
Others have enounced the sumption in various forms, for ex-
ample : If it be impossible but that yov. recover from, the present
disease, etc., — or — If it be true that you loiU recover from this
disease, — or — If it be decreed by God thai
ts various esigna- ^^^ ^^.^ ^^^ ^.^ ^r, ^^^.^ disease, and so likewise
tlons. ^ '' , .,
in different manners; according to which like-
wise the question itself has obtained various titles, as Argument
1 See Mennjre on Diogenes Lnertius, L. ii. Gassendi, OptTa,X. i. Bt Log. Orig. €t Tmr., It
p. 123. — Ed. [FaccJolati, Acroasis, v. p. 55. i. c. 6. p 51]
2 Krug, Logik, i 117, p. 424. — Ed.
I
L
Lkct. XXIIL logic. 331
De Fato — De Possihilihus — De JOibero Arbitrio — De Promden-
tia — De Divinis Decretis — De Futuris Contingentibus — DePhys-
ica Prcedeterminatione, etc. No controversy is more ancient,
none more universal, none has more keenly agitated the minds of
men, none has excited a greater influence upon religion and morals ;
it has not only divided schools, but nations, and has so modified
not only their opinions, but their practice, that whilst the Turks, as
converts to the doctrine of Fate, take not the slightest precaution
in the midst of pestilence, other nations, on the contrary, who admit
the contingency of second causes, carry their precautionary policy
to an opposite excess.
The common doctrine, that this argument is an invention of the
Stoics, and a ground on which they rested their
Its history. , . ^ ■, ^ ■ ^ •
doctrme oi the physical necessitation oi human
action, is, however, erroneous, if we may accord credit to the testi-
mony of Diogenes Laertius, who relates, in the Life of Zeno, the
founder of this sect, that he bestowed a sum of two hundred minae
on a certain dialectician, from whom he had learned seven species of
the argument called the Xoyos ■^epl^wv, metens, or reaper, which diffei-s
little, if at all, from the ignava ratio} For how this sophism is
constructed, and with what intent, I find recorded in the commen-
tary of Ammonius on the book of Aristotle Ilept "Etpfxrjvda'i? Of
the same character, likewise, is the argument called the Xoyos Kvpi-
cwQjv, the ratio dominans, or controlling reason, the process of which
Arrian describes under the nineteenth chapter of the second book
of the sayings of Epictetns.'' The lazy reason, — the reaper, — and the
controlling reason, are t!)us only various names for the same process.
In regard to the vice of this sophism, "it is manifest that it lies in
the sumption, in which the disjunct members
e vice o js ^^^ imperfectly enounced. It ought to have
sophism. .
been thus conceived : If I ought to exert my-
self to effect a certain event, which I cannot, however, of myself
effect, this event must either take place from other causes, or it
must not take place at all. It is only under such a condition that
my exertion can, on either alternative, be useless, and not if the
event depend wholly or in part for its accomplishment on my exer-
tion itself, as the conditio sine qua non." * It is plain, however, that
1 See Laertins, vii. 25. The observation in ered from Arrian, but not the nature of the
the text is from Facciolati, Acroasis, v. p. 57, argument itself. It is also mentioned, though
ed. 1750. — Ed. not explained, by Lucian, Vit. Auct., c. 22
Plutarch, Sympos., i. 1, 5. Gellius, N. A., i.2
2 F. 91 b, ed. Aid. Tenet., 1546. — Ed
Compare Facciolati, Acroasis, v. p. 67. — Eu
uompare facciolati, >ieroasis, 1
8 The purpose of this sophism may be gath- •* Krug, Logik, p. 424. — Ed.
832 LOGIC. Lect. XXIII.
the refutation of this sophism does not at all affect the doctrine of
necessity ; for this doctrine, except in its very absiirdest form, — the
Fatum Turcicum^ — makes no use of such a reasoning.
" The third fallacy is the Sophisma polyzeteseos or qucestionis dit-
plicis^, — the sophism of cofitinuous questioning^
(c) Sophisma polyze- i • u a^ .. £• xi • -UM-^ c
which attempts, trom the impossibility oi assign-
ing the limit of a relative nbtiou, to show by
continued interrogation the impossibility of its determination at
all. There are certain notions which are only conceived as relative,
— as proportional, and whose limits we cannot, therefore, assign by
the gradual addition or detraction of one determination. But there
is no consequence in the proposition, that, if a notion cannot be
determined in this manner, it is incapable of all determination, and,
therefore, absolutely inconceivable and null."^ Such is the Sorites,
the nature of which I have already explained to
Its various designa- ^^^ rpj^j^ reasoning, as applied to various ob-
tions. ^ _ o' rr
jects, obtained various names, as, besides the
Sorites or Acervus, we have the crescens^ — the <^taXaKp6% or calvus^
— the virepSeTiKo^, superpositus or superlativiis* — the rjo-vxaZoyv or
qviescens, etc., etc.* The Sorites is Avell defined by Ulpian,*' a soph-
ism in which, by very small degrees, the disputant is brought from
the evidently true to the evidently false. For example, I ask, Does
one grain of corn make up a heap of grain ? My opponent answers, —
No. I then go on asking the same question of two, three, four, and
so on ad infimtuin^ nor can the respondent find the number at which
the grains begin to constitute a heap. On the other hand, if we
depart from the answer, — that a thousand grains make a heap, the
interrogation may be continued downward to unity, and the answerer
be unable to determine the limit where the grains cease to make uj)
a heap. The same process may be performed, it is manifest, upon
all the notions of proportion, in space and time and degree, both in
continuous and discrete quantity.'
The fourth and last fallacy of this class is the sophisma hetero-
zeteseos, or sophism of counter-questioning^ and as applied to vari-
1 Krng, Logik, S H"- — Ed. « Leg', 177. De Verb Signif. "Natnra cavil-
2 Wyttenbacli, ilrf Ptut. De Sera Num. Vind., Jationis, quam Graeci (ru>p(iT7{v appellarnnt,
p. 559; Pra-cepia Phil. Log , p. iii. c. 9, § 4. — Ed. haec est, ut ab ea ab evidenter veris per brev-
3 Diog. Laert., ii. 103. Cf. Gasseudi, De issimas mutationes disputatio ad ea quas evi-
Log. Orig., c. 3. — Ed. dentur falsa sunt perducatur." Quoted by
4 Epictetus, Dissert., iii. 2, 2. As interpreted Gassendi, De Logieee Origine et Yarittate., L. i.
by Gassendi, De Log. Orig., c. 6. But Ibe c. 3, p. 41, aud by Menage, Ad Laert., ii. 108.
true reading is probably inro^eTtKOVs. See — Ed.
Scbweigbasuser's note. — Ed. 7 Krug, Logik, { 117. — Ed.
« Cicero, Acwl., ii. 29. Epictetus, Dissert. 8 [See Gassendi, Opera, 1. 1. De Log. Orig
ii. 18, 19. — Ed. et Var. L. i. c. 6, p. 61]
Lkct. XXm. LOGIC. • 383
ous objects, it obtained, among tlie ancients, tlic names of the Di-
lemma^ — tJic Cornidus^' — the TAti(jiosus^ — the
(d) sophisma hctero. ^^^.j.m,^.^ _ fj^,, ^lentkus^ — the Fulhuis^ — the
z'teseos.
I^JlectraS' — the Obeekitus^ — the liec'njrocns,^ — •
Its vunous names. ' i i ^
tlie Crocodilinifsj'' — the oiJrt?,-'^ — the Induct io
imperfecta /^^ and to tliis should also be refei-rcd the Ass of Buri-
danus.^- "It is a hvj^otlielico-disjunctivo rea-
Its character. . i • i ' • • • i
soning, wlncii rests on a certain suj)])osition, and
which, through a reticence of this supposition, deduces a fallacious
inference. To take, for an exaini)le of tliis fdlacy, tlie /cspanro? or
Cornutus: — it is asked: — Have }ou east your horns":' — If you
answer, I have; it is rejoined, Then you have had horns: if you
answer, I have not, it is rejoined. Then you have them still.'"' — To
this question, and to the inferences from it, the disjunctive ])roposi-
tion is suj)}iosed, — A certain subject has either had horns or has
theni still. This disjunction is, however, only coi'rcct il'llie question
is concerning a subject to which horns preA'iously belonged. If I
<lo not suppose this, the ilisjmiction is f ilse ; it must, (■(jiiseipiently,
thus run : — a certain subject has cither had or not had horns. In
the latter case they could not of course be cast. The alternative
inferences (thai you hare hud ththt, or then you linn: thrin .it ill)
liave no longer ground or plausibility." To take anotlicr instance in
the LUiqiofius or jRecip/'OCu.s. Of ihc history
rhe Litigiosus. .
of this iinnous dilemma there are two accounts,
the Greek and the Konum. The Iionum account is gi\-en us by
Aulus Gellius,'"' and is there told in rehition to an .'u-tiou l^etween
I'rotagoras, the prince of the Sophists, and
The case of Protag- E^.^tlilus, a voung uiau, his disciidc. The disci-
oras and Luatlilus. ' ' ■- _ _ ^
pie had covenanted to give Iiis master a lai-ge
sum to accomplish him as a legal rhetorician; the one half of the
siuii was paid down, uvA the other vras to be paid on the day when
Kuathliis should plerul ;ind gain his first cause. But when the
i IlcrmoErciies, /)>■ Ln-nii.. L. iv., and Pro- "^ Anius (A'Uius, N. A., L. v. c. 10. 11 — il;>^
l'-^^ ail H-r!noi;nirm. See Walz's IVi^tnrni n Liician, / c. (;ninti;i:iii, I.i.^:. Om,'., i. IT
I'Vwc/, vol. iii. p. 107, iv. j). 11. — Kd. ;". (T. >Ienr._<re, .4-/ Xl/w;'. L«fr;., L. ii lOS. -
-' Si^neca, Epi.^t., l.j. 3Ie)iage, Ad Dlog; Ln- Kd.
cr«., L.ii 108. — Ki). 1" Aminonin.s, Ad Arisi. C<it.^.. f. r,<. Cf.
•' Diop;. Laert., L. ix. 23. Aristotle, P/jt/,'!., Meua.trc, /or. c/j. — I.'.n,
vi. 9. Soph. Ecnri,., 24. — Kl). H Cicero, /)-; In rnninnr. L. i. c. SI. - Kn.
•» 5Ienajre. yl / Dii^s:. Lneit., 1^ ii.lO,'^. Cicero, I- See DenzinL'er. Ln-^iL-. \ r,71, IVoiri \vliom
.IfO'/., ii. 29. — En. tliese de.<iLri;ntions are taken. llei'J's Works,
■> Diojr. Laert., ii. 108. — Kd. p. 2,38. — Kd.
•5 Luc i an, Vit. And., 5 22. Cf. Menage, .W ].'! Diog. Laert., vii. 187.— Kd.
Diog. Laert.., L. ii. 108. — Kd. l-I Krug, Losik, \). ^'I'o. — Ed.
^ Menage, ibid. — Ed. 15 L. v. c. 10.
334 LOGIC. Lect. XXIU
scholar, after the due course of preparatory instractioB, was not in
the same hurry to commence pleader as the master to obtain the
remainder of his fee, Protagoras brought Euathlus into court, and
addressed his opponent in the following reasoning : — Learn, most
foolish of young men, that however matters may turn up (whether
the decision to-day be in your favor or against you), pay me my
demand you must. For if the judgment be against you, I shall
obtain the fee by decree of the court, and if in your favor, I shall
obtain it in terms of the compact, by which it became due on the
very day you gained your first cause. You thus must fail, either by
judgment or by stipulation. To this Euathlus rejoined: — Most
sapient of masters, learn from your own argument, that whatever
may be the finding of the court, absolved I must be from any claim
by you. For if the decision be favorable, I pay nothing by the sen-
tence of the judges, but if unfavorable, I pay nothing in virtue of
the compact, because, though pleading, I shall not have gained my
cause. The judges, says Gellius, unable to find a ratio decidendi,
adjourned the case to an indefinite day, and ultimately left it unde-
termined. T find a parallel story told, among the Greek writers, by
Arsenius, by the Scholiast of Hermogenes, and
^'^,1.*!°** "* by Suidas,^ of the rhetorician Corax (anqlice
rax and Tisias. •' ' ■ . ^ ^f
Crow) and his scholar Tisias. In this case, the
judges got off by delivering a joke against both parties, instead of a
decision in favor of either. We have here, they said, the plaguy
Qgg of a plaguy crow, and from this circumstance is said to have
originated the Greek proverb, kokov K6paKo<s kukov wov.
Herewith we terminate the First Great Division of Pure Logic,—
Stoicheiology, or the Doctrine of Elements.
1 [Prolegomena to Hermogenes, in Walz's 313, 314. Quoted by Sigwart, LogiU, f 333, p
Rhttores Graci, torn. iv. pp. 13, 14. Arsenii 211, 3d edit. Suidaa, quoted by Schottua
Tioletum, edit. Walz, Stuttgard, 1832, pp. Adagia Gracorum, p. 4£0, 1612.]
LECTURE XXIV.
PURE LOGIC.
PART II.-METHODOLOOY.
SECTION I. — METHOD IN GENERAL.
SECTION IL — METHOD IN SPECIAL, OR LOGICAL METHODOLOGY
L — DOCTRINE OF DEFINITION,
Gentlemen, — We concluded, in our last Leetui'e, the considera-
tion of Syllogisms, viewed as Incorrect or False ;
e 10 o ogy. .^ other words, the doctrine of Fallacies, in so
far as the fallacy lies within a single syllogism. This, however, you
will notice,. does not exhaust the consideration of fallacy in general,
for there are various species of fjxlse reasoning which may affect a
Avhole train of syllogisms. These — of which the Petitio Prin-
cipii, the Ignoratio Elenchi, the Circnlus, and the Saltits in Con-
cludendo, are the principal- — will be appropriately considered in
the sequel, when we come to treat of the Doctrine of Probation or
Demonstration. With Fallacies terminated the one Grand Division
of Pure Logic, — the Doctrine of Elements, or Stoicheiology, —
and I open the other Grand Division, — the Doctrine of Method, or
Methodology,' — with the following paragraph.
^ LXXX. A Science is a complement of cognitions, having,
^^^^ „ .^ ^ in point of Form, the character of Logical
Par. IiZXZ. Method i ' C
in general. Perfection ; in point of Matter, the charac-
ter of Real Truth.
The constituent attributes of Logical Perfection are the Per-
spicuity, the Completeness, the Harmony, of Knowledge. But
the Perspicuity, Completeness, and Harmony of our cognitions
are, for the human mind, possible only through Method.
Method in general denotes a procedure in the treatment of
an object, conducted according to determinate rules. Method,
336 LOGIC. Lect. XXIV.
in reference to Science, denotes, therefore, the arrangement
and elaboration of cognitions, according to definite rules, with
the view of conferring on these a Logical Perfection. The
Methods by which we proceed in the treatment of the objects
of our knowledge are two ; or rather Method, considered in its
integrity, consists of two processes, — Analysis and Synthesis.
I. The Analytic or Regressive ; — in which, departing from
the individual and the determined, we ascend always to the
more and more general, in order finally to attain to ultimate
principles.
II. The Synthetic or Progressive ; — in which we depart
from principles or univereals, and from these descend to the
determined and the individual.
Through the former we investigate and ascertain the reality
of the several objects of science ; through the latter we con-
nect the fragments of our knowledge into the unity of a system.
In its Stoicheiology, or Doctrine of Elements, Logic considers
the conditions of possible thought ; for thcnght
Explication. ^^^ ^^^ y^^ exerted under the general laws of
Possibility and Per- • r^ -,• • -niin nr- -i -ii i
cection of Thought. Identity, Contradiction, ll<xcluded Middle, and
Reason and Consequent ; and through the gen-
eral forms of Concepts, Judgments, and Reasonings. Xl^ese, there-
fore, may be said to constitute the Elements of thought. But we
may consider thought not merely as existing, but as existing well ;
that is, we may consider it not only in its possibility, but in its per-
fection ; and this perfection, in so far as it is dependent on the form
of thinking, is as much the object-matter of Logic as the mere pos-
sibility of thinking. Now that part of Logic which is conversant
with the . Perfection, with the Well-being of thought, is the Doc-
trine of Method, — Methodology.
Method in general is the regulated procedure towards a certain
end ; that is, a process governed by rules, which
-what ^ ' g"itle us by the shortest way straight towards
a certain point, and guard us against devious
aberrations.^ Now the end of thought is truth, — knowledge, —
1 [On Method, see Alex. Aphrod., In Anal, nesius, De Cnnstitvtiorie Artis Diahctlca, p. 43
Prior., f. 3b, Aid. 1520. Ammonius, //» /Voosm. et scq., cA. 1554, with relative comraentarr.
Porphyrii, f. 21b, Aid. 1546. Philoponus, In Timpler, Stjstima Logicft, L. iv. c. viii. p. 716
An. Prior., f. 4. /« An. Post., f. 94. Eustra- et seq. G. Downam. Commentarii in P. Rami
tins, III An. Post. ff. lb, 53b. See also Molin- Dialecticam, L. ii. c. 17, p. 472 et seq. -On the
jcus, Zabarella, Nunne.«ius, Timpler, Dow- distinction between Method and Order, see
nam.] [Slolin.-cus, Logica, L. ii., De Methodo, lectures on Metaphysics, lecL. rl. p 6S, and
p. 245 et seq. Zaharella, Oj)era Lngica, De note. — Ed.)
Metho'lis, L. i. c. 2, p. 131. Peter John Nun- *
Lect. XXIV. LOGIC. 337
science, — expressions whicli may here be considered as convertible.
Science may, therefore, be rejjarded as the per-
Science, — what, n • r
lection of thought, and to the accomphshment
of this perfection the Methodology of Logic must be accommodated
and conducive. But Science, that is, a system of true or certain
knowledge, supposes two conditions. Of these, the first has a rela-
tion to the knowing subject, and supposes that
i nd'siateriai ^^ what is known is known clearly and distinctly,
completely, and in connection. The second has
a relation to the objects known, and supposes that what is known
has a true or real existence. The former of these constitutes the
Formal Perfection of science, the latter is the Material.
Now, as Logic is a science exclusively conversant about the
form of thought, it is evident that of these
gicaesmoac- ^^^^ conditions, — of these two elements, of
count only the formal
perfection of science. scienco or perfect thinking, Logic can only take
into account the formal perfection, which may,
therefore, be distinctively denominated the logical perfection of
thought. Logical Methodology will, therefore,.
Logical Methodol- , ^, ... c ^, { n i
. , be the exposition oi the rules and ways by
ogy, — what. ^ j •/
which we attain the formal or logical perfec-
tion of thought.
But Method, considered in general, — considered in its unre- -
stricted universality, — consists of two proces.ses,.
Method in general correlative and complementary of each other.
consists of two cor- -, . i n T i i i
relative and compie- For it proceeds Cither from the whole to the
mentary processes,— parts, or from the parts to the whole. As pro-
Analysis and synthe- ceeding from the whole to the parts, that is, as
resolving, as unloosing, a complex totality intO'
its constituent elements, it is Analytic ; as proceeding from the
parts to the whole, that is, as recomposing constituent elements-
into their complex totality, it is Synthetic. These two processes
are not, in strict propriety, two several methods, but together con-
stitute only a single method. Each alone is imperfect ; — each is
conditioned or consummated by the other ; and, as I formerly ob-
served,^ Analysis and Synthesis are as necessary to themselves and
to the life of science, as expiration and inspiration, in connection,,
are necessary to each other, and to the possibility of animal
existence. •
It is here proper to make you aware of the confusion which
prevails in regard to the application of the terms Analysis and
1 See Lecture*, on Metaphysics, p. 70- — £)I>.
43
LOGIC.
Lkct. XXIV.
ConfUsion in regard
to the application of
the terms Analysis
and Synthesis.
abuse.
These counter pro-
cesses as applied to
the countet- wholes of
Coniprelifusion and
Kxtensioii, correspond
with each other.
Synthesis} It is manifest, in general, from the meaning of the
words, that the term analysis can only be applied
to the separation of a whole into its parts, and
that the term synthesis can only be aj^plied to
the collection of parts into a whole. So far,
no ambiguity is possible, no room is left for
But you are aware that there are different kinds of whole
and parts; and that some of the wholes, like
the whole of Comprehension (called also the
Metaphysical)^ and the wliole of Extension,
((ialled also the Logical), are in the invei-se ratio
of each other: so that what in the one is a part,
is necessarily in the other a whole. It is evi-
dent, then, that the counter processes of Analysis and Synthesis, as
applietl to these counter wholes and parts, should fall into one, (xr
correspond ; inasmuch as each in the one quantity should be dia-
metrically opposite to itself in the other. Thus Analysis, as applied
to Comprehension, is the reverse process of Analysis as applied to
Extension, but a corresponding process with Synthesis ; and vice
versa. Now, should it happen that the existence and opposition of
the two quantities are not considered, — that men, viewing the
whole of Extension or the whole of Comprel\ension, each to the
exclusion of the other, must define Analy!5is and Synthesis with
reference to that single quantity which they exclusively take into
account; — on this supposition, I say, it is manifest that, if dif-
ferent philosophers regard different wholes or
quantities, we may have the terms analysis and
synthesis absolutely used by different philoso-
phers in a contraiy or reverse sense. And this
has actually happened. The ancients, in gen-
eral, looking alone to the whole of Extension, use the terms analysis
Ueiice the terms
Analysis and Synthe-
sis used in a contrary
sense.
1 [Zaba pel la. Opera Logica, Liber de Regressu,
pp. 4S1, 489. See also, In Anal. Poster.. L. ii.
te.\t 81, pp. 1212, 1213. Molinseus, Logica, L.
ii. Appendix, p. 241 et seq., who notices that
both the Analytic and Synthetic order may
proceed from the general to the particular.
See also, to the same effect, HofFbauer,t/6fr
rf(> Analysis in dtr Phitosophie. p. 41 et seg.,
Halle, 1810. Ga.«sendi, P/iysica, Scctio iii.
Memb. Part, L. ix. Opera, t. il p. 460. Vic-
torUi, iVei«t natHrlickere Darstellung der Logik,
I 214. Trendelenburg, Elementa Logicrs Aris-
tntelirrr, p. 89. Troxler, Logik, ii. p. 100. n. *».
Knig, Lo^'ik, § 114. p. 406, n. **, and § 120, p.
431. Wyttenbach makes Synthetic method
pngivss from particulars to universals ; other
logicians generally the reverse.] — (See bib
Prarrpta Phil. Logi.-er, T. Ill c. i. S 3, p. 84,
1781. — "Mentem suaptc natura Syntheticarr,
Mctliodum sequi, eaque ad universales idea»
pervenire Contrarium est iter An?
lyticaj Methodi, quae ab universalibus initiuro
ducit et ad peculiaria progreditur, dividends
Genera in suas Formas.-' ''Contra commw
nem sensum et vcrborum naturara, Synthet-
icam vocani Jlcthodnm, qua; dividit, Anj.
lyticam contra, quae componit." Pra;f sub
Jin. In the edition of the Pr/rcepta by Miaa,
Wyttenbach is made to say precisely tho re
verse of what he lays down in the origins'
edition. See Prcec. Phil. Log., ed. Maafis, j
64. — Ed.]
Lkct. XXIV. LOGIC. 339
and analkjtic simply to denote a division of the genus into species,
— of the species into individuals ; the moderns, on the other hand,
in general, looking only at the whole of Comprehension, employ
these terms to express a resolution of the individual into its varions
attributes.^ But though the contrast in this respect between the;
ancients and moderns holds in general, still it is exposed to sundry
exceptions ; for, in both |>criods, there are philosophers found at the
same game of cross-purposes with tlicir contemporaries as the an-
cients and moderns in general are with each other. This difference,
Avhicli has never, as far ts, I know, been fully observed and stated,
is the cause of great confusion and mistake. It is pi'oper, therefore,
when we use these terms, to use them not in exclusive relation to
one whole more than to another; and, at the same time, to take
care that we guard again.s;t the misapprehension that might arise
from the vague and one-sided view which is now universally preva-
lent. So much for the meaning of the words analytic and synthetic,
which, by the way, I may notice, ait;, like most of our logical terms,
laken from Geometry.^
The Synthetic Method is likewise called the Progressive ; the
Analytic is called the Rerjressive. Now it is
TijeSyntiieticMetii. plain that this application of the terms progres-
od has been called the ^^^^ ^^^^^ regressive is altogether arbitrary. For
I'rogressive, and the . r^ ''
Analytic the Regres- the unport of these words expresses a relation
.-ive. Tiicse desigiia- to a certain point of departure, — a termintis o
(ions wholly arbitrary, quo, Vir\(\ to a certain point of termination, — a
;ind of various appli- . , i • <» i i ^
^jjj^^ terminus ad quern; and it these have only an
arbitrary existence, the correlative words will,
consequently, only be of an arbitrary application. But it is mani-
fest that the point of departure, — the point from which the Pro-
gressive process starts, — may be either the concrete realities of our
experience, — the principiata, — the notiora nobis; or the abstract
generalities of intelligence, — the principia, — the notiora natura.
Each of these has an equal right to be regarded as the starting-
point. The Analytic process is chronologically first in the order of
knowledge, and we may, therefore, reasonably call it the progres-
sive, as starting from the primary data of our observation. On the
other hand, the Synthetic process, as following the order of consti-
tution, is first in the order of nature, and we may, therefore, like-
wise reasonably call it the progressive, as starting from the primary
elements of existence. The application of these terms as synonyms
1 [See Aristotle, Fkysica, Ii..iv. c. 3. Timp- Analysis of Geometry, see Plotinus. ^tinead:..
ler, Logicm Systema, L. ii. c. i. qu. 11. p. 24S.] iv. L. ix. c. 5. Philoponus, la An. Post.r f
2 See above, p. 196, u. 4. — Ed. [On the 36a,Venet. 1534.1
840 LOGIC. Lect. xxrv.
of the analytic and synthetic processes, is, as wholly arbitrary, man-
ifestly open to confusion and contradiction. And such has been
the case. I find that the philosophers are as much at cross-purposes
in their application of these terms to the Analytic and Synthetic
processes, as in the application of analysis and synthesis to the dif-
ferent wholes.
In general, however, both in ancient and modern times, Sj-nthesis
has been called the Progressive^ Analysis the
In general, Synthe- Regressive^ process ; an application of terms
si8 has been desig- which has probably taken its rise from a passage
Dated the Progressive, . » . i , i ,
and Analysis the Kc- ^^ Aristotle, who says that there are two ways
gressive Process. \ of scientific procedure, — the one from princi-
ples (aTTo ruiv a.pywv\ the Other to principles {IttX
Tas apx^s). From this, and from another similar passage in Plato, (?)
the term progressive has been applied to the process of Comprehen-
sive Synthesis {progrediendi a principiis ad principiata)^ the term
regressive^ to the process of Compi*ehensive Analysis {progrediendi
a principiatis ad principia.y
So much for the general relations of Method to thought, and the
general constituents of Method itself. It now
Method in special. . . ' . , , . . . . ,
remains to consider what are the particular ap-
plications of Method, by which Logic accomplishes the Formal Pei-
fection of thought. In doing this, it is evident that, if the formal
perfection of tliought is made up of various virtues, Logic must
accommodate its method to the acquisition of these in detail ; and
that the various processes by which these several virtues are ac-
quired, will, in their union, constitute the system of Logical Method-
ology. On this I will give you a paragra^ih.
^ LXXXI. The Formal Perfection of thought is made up of
„ ,^^^ the three virtues or characters: — 1°, Of
Par. IiXXXI. Logi- ^ '
cai Methodology,- its Clearness; 2°, Of Distinctness^ involving
Three Parts. Completmess ; zndi, Z"" , 0^ Ilarmouy . The
character of Clearaess depends principally on the determination
of the Comprehension of our notions ; the character of Dis-
tinctness depends principally on the development of the Exten-
sion of our notions ; and the character of Harmony, on the
\ Elk. Nie,\.2(i). The reference to Plato, quoted in Is. Casaubon's note. On the views
whom Aristotle mentions as making a similar of Method of Aristotle and Plato, see Schcib-
distinction, is probably to be found by com- ler and Downam.] [Scheibler, Op«ra Logicn, ■
paring two separate passages in the Republic, Pars, iv.. Tract. Syllog., c. xvii., Dt Methodn,
B. Iv. p. 435, vi. p. 504. — Ed. [Plato is said tit. 7, p. 603. Downam, Cowj. in P. Rami Dia-
to have taught Analysis to Leodamas the Ucticam, L. U. c. 17, p. 482. — £d.]
rhasian. See Laertlus, L. lii. 24, and Proclus,
Lkct. XXIV. LOGIC. 341
mutual Concatenation of our notions. The rules by which
these three conditions are fulfilled, constitute the Three Parts
of Logical Methodology. Of these, the first constitutes the
Doctrine of Definition ; the second, the Doctrine of Division ,'
and the third, the Doctrine of Probation}
"When we turn attention on our thoughts, and deal with thera
to the end that they may be constituted into a
scientific whole, we must perform a three-fold
operation. We must, first of all, consider what we think, that is,
what is comprehended in a thought. In the second place, we must
consider how many things we think of, that is, to how many objects
the thought extends or reaches, that is, how many are conceived
under it. In the third place, we must consider why we think so
and so, and not in any other manner; in other words, how the
thoughts are bound together as reasons and consequents. The first
consideration, therefore, regards the comprehension ; the second, the
extension ; the third, the concatenation of our thoughts. But the
comprehension is ascertained by definitions ; the extension by divi-
sions; and the concatenation by probations."^ We proceed, there-
fore, to consider these Three Parts of Logical Methodology in
detail ; and first, of Declaration or Definition, in regard to which I
give the following paragraph.
f LXXXII. How to make a notion Clear, is shown by the
logical doctrine of Declaration^ or Defini-
par. LXXXII. 1. The fi^jj^ j^ its widcr scnsc. A Declaration (or
Doctrine cf Deolara- t\ n • ' • • • -t • .^
tion or Definition. Definition in its Wider sense) is a Categori-
cal Proposition, consisting of two clauses or
members, viz., of a Subject Defined (menihruni definitum) and
of the Defining Attributes of the subject, that is, those by which
it is distinguished from other things {membrum definieyis). This
latter member really contains the Definition, and is often itself
so denominated. Simple notions, as containing no plurality of
attributes, are incapable of definition.'
1 Krug, Logilc, § 121a. — Ed. [Ramus was 68, and makes four special logical methods,
the first to introduce Metliod as a part of Division, Definition, Analysis, Demonstra-
I-ogic under Syllogistic (see his Dialectica, L. tion. Eustachius treats of Method under
ii c 17), and the Port Royalists (1S62) made Judgment, and Scheibler under Syllogistic.J
if ix fourth part of logic. See La Logique. ou [Eustachius, Summa Philosophice, Logica, P. ii-
/.■ Art de denser, Prem. Dis., p. 26, pp. 47, 50. Tract. 2. De Methodo, p. 106, ed. Lugd. Ba-
(;uat. Part., p. 445 (t seq. ed. 1775. Gassendi, tav., 1747. First edition, 1609. Scheibler,
I.. Iii.s liiititiitio Logica^ has Pars iv., De Meth- Opera Logica, Pars iv. C. xviii. p. 595 et seg.—>
<■'■'■ Ue died in 1655; his Logic appeared Ed]
pu-thnmously in 1658. John of Damascus 2 Krug, Log^i/fc, §121*. — Ed.
»-, e.>k8 sti ongly of Method in his Dialectic, ch. 8 Krug, Logik, { 1216. — Ed.
342 LOGIC. Lect. XXTV.
The terras declaration and definition^ which are here used as appli-
cable to the same process, express it, however,
p ica jon. .^ different asi)ects. The term declaration (dec-
The terms Declara- ^ ^
tion and Definition laratio) is a wofd somcwhat vaguely employed
express the same pro- in English ; it is here used strictly in its proper
cess in difierent as- g^^^g^ ^^ throwing light upon,—- cleaHng up.
The terra definition {definition is employed in a
more general, and in a more special, signification. Of the latter we
are soon to speak. At present, it is used simply in the meaning of
an enclosing within limits^ — the separating a thing from others.
Were the terra declaration not of so vague and vacillating a sense,
it would be better to employ it alone in the moi'e general accepta-
tion, and to reserve the term definitiojt for the special signification.
% LXXXIII. The process of Definition is founded on the
logical relations of Subordination, Coordi-
par. LXXXIII. Defl- nation, and Congruence. To this end we
nition in its stricter discriminate the constituent characters of a
•ense, — wbat.
notion into the Essential^ or those which
belong to it in its unrestricted univereality, and into the Unes-
sential, or those which belong to some only of its species. The
Essential are again discriminated into Original and Derivative^
a division which coincides with that into Internal or Proper,
and Exteiwial. In "-ivinf; the sum of the original characters
constituent of a notion, consists its Definition in the stricter
sense. A Definition in the stricter sense must consequently
afford at least two, and properly only two, original character,
viz., that of the Genus immediately superior {genus proximum)y
and that of the Difference by which it is itself marked out
from its coordinates as a distinct species {nota specialise differ-
entia specifica)}
Declarations (or definitions in the wider sense) obtain various
denominations, according as the process is per-
Expiication. formed in different manners and degrees. A
Declaration is called an Explication {explication,
Explication. when the predicate or defining member indcter-
Exposition. minately evolves only some of the characters
belonging to the subject. It is called an Exposi-
tion {exposiCio), when the evolution of a notion is continued through
I [Cf. Aristotle, rop»>a, i. 6. Keckermann, pp. 199,656. Scheibler, 7l>p>ca, c 30. Riohter,
SyMema Loj^ica Minus, L i. c. 17. Optra.t i. Logik, p. 94.]
L;:ci. XXIV. LOGIC. 8^3
several explications. It is called a Description (<kscriptio), when
the subject is made known through a number
Description. . . _,. ,, • • t n t
„ „ ... „ „ , or concrete characteristics. J^ mally, it is called
Definition proper. •' '
.1 Dejinition Proper, when, as I have said, two
of the essential and original attributes of the defined subject are
given, whereof the one is common to it with the various species of
the same genus, and the other discriminates it from these.^
"Definitions are distinguished also into Verbal or Nominal, into
Real, and into Genetic {dejinitiones noniinales.
Definitions, — jJom- reulcs, geneticce), diCcovdim^ as they are conver-
inai, Keai, and Gene- ^^^^ ^^-^j^ ^j^^ meaning of a term, with the nature
tic. ^ .
of a thing, or with its rise or production." Nom-
inal Definitions are, it is evident, merely explications. They are,
therefore, in geiicnd only used as preliminary, in order to prepare
the way for more perfect declarations. In Real Definitions the
thing defined is eousiJered a^ already there, as existing (ov), and
the notion, therefore, as given, precedes the definition. They are
thus merely analytic, that is, nothing is given explicitly in the predi-
cate or defining member, which is not contained implicitly in the
subject or member defined. In Genetic Definitions the defined
subject is considered as in tlie progress to be, as becoming yiyvo/*c-
vqv, the notion, therefore, has to be made, and is the result of the
definition, which is consequently synthetic, that is, ])laces in the
predicate or defining member more than is given in the subject or
member defined. As examples of these three species, the following
three definitions of a circle may suftice '.- — 1. The Nominal Defini-
tion,— The word circle signifies a uniformly curved liiie. 2. Thti
Real Definition, — A circle is a line returning upon itself, of which
all the parts are equidistant from a given point. 3. The Geiietio
Definition, — A circle is formed when we draw around, and always
at the same distance from, a fixed point, a movable point which
leaves its trace, until the termination of the movement coincides
witli the commencement.'' It is to be observed that only those
notions can be genetically defined, which relate to quantities repre-
sented in time and space. Mathematics are principally conver-
sant with such notions, and it is to be noticed that the mathematician
usually denominates such genetic definitions real definitions, while
the others he calls without distinction nominal definitions"*
The laws of Definition are given in the following paragraph.
1 Cf. Krug, Logik, § 122. — Ep. tion, from Wolf, Philosopkia RcUionalis, i 19L
2 [Cf. Reasch, Systema Lo^eum, § 309 et — Ed.
«7l * K^rug) Logik, § 122. Anpi. 3, pp. 443, 44a
3 This example is taken, with some altera- — Ed.
344 LOGIC. Lect. XXIV.
% LXXXIV. A definition sliould be Adequate (adequata),
that is, the subject defined, and the predi-
.^ ^ cate dofinint;, should be equivalent or ot the
nition, — its Laws. o' T.
same extension. If not, the sphere of the
predicate is either less than that of tlie subject, and the defini-
tion Too Narrow {angustior), or greater, and the definition
Too Wide {latior).
II. It should not define by Negative or Divisive attributes
{Ne sit negans, ne fiat per disjunc(a).
III. It should not be Tautological, — what is contained ia
the defined, should not be repeated in the defining clause (Ne
sit circidus vel diallelon in defi?iiendo).
IV. It should be Precise, that is, contain nothing unessential,
notliing superfluous (Definitio ne sit abundans).
V. It should be Perspicuous, that is, couched in terms intel-
ligible, and not figurative, but proper and compendious.'^
The First of these rules: — That the definition should be ade-
quate, that is, that the definiens and definitum
pica ion. should be of the same extension, is too manifest
First Rule. , ...
to require much commentary. Is the definition
too wide ? — then more is declared than ought to be declared ; is it
too narrow ? — then less is declared than ought to hv declared ; —
and, in either case, the definition does not fully accotnpllsh the eiid
which it proposes. To avoid this defect in definition, we must
attend to two conditions. In the firet place, that attribute should
tie given which the thing defined has in common with others of the
same class; and, in the second place, that attribute should 'be given
which not only distinguishes it in general from all other things, but
proximately from things which are included with it under a couitnon
class. This is expressed by Logicians in the rule — Definitio con-
stet genere proximo et differentia ultima, — Let the definition consist
of the nearest genus and of the lowest difference. But as the no-
tion and its definition, if this rule be obeyed, are necessarily i<lentical
or convertible notions, they must necessarily have the s:mie extent ;
consequently, everything to which the definition ap[)lies, and noth-
ing to which it does not apply, is the thing defined. Thus : — if
the definition, Man is a rational animal, be adequate, we shall be
able to say — Every rational animal is human: — nothing lohich is
not a rational animal is human. But we cannot say this, for
1 Cf. KruR, Logik, § 12.3. — Ed. [Victorin. Definitione, Oiiera, p. (H8 ft ieq. Buffier. Vrri-
Logik, i 22S ft sfq. Sig-wa.rt, Ham/buck zuVor- ttz de Consfqutnce, \ Ab-b\. Goclenius, L«x»-
tfungrn iibrr die Logik, J 371. Boetbius, De con Phitosopkicum, f. Definitio, p. 600.]
Lect. XXIV. LOGIC. 345
though this may be true of this earth, we can conceive in other
worlds rational animals which are not human. The definition is,
therefore, in this case too wide ; to make it adequate, it will be nec-
essary to add terrestrial or some such term — as, Man is a rational
animal of this earth. Again, were' we to define Man, — a ration-
ally acting animal of this earth, — the definition would be too
narrow ; for it Avould be false to say, 7io animal of this earth not
acting rationally is human, for not only children, but many adult
persons would be excluded by this definition, which is, therefore, too
narrow.^
The Second Rule is, — That the definition should not be made by
negations, or disjunctions. In regard to the for-
SecondBuIe. ,. ^i ^ i, u j ii
mer, — negations, — that we should define a
thing hj what it is, and not by what it is not, — the reason of the
rule is manifest. The definition should be an afiirmative proposition,
for it ought to contain the positive, the actual, qualities of the no-
tion defined, that is, the qualities which belong to it, and which
must not, therefore, be excluded from or denied of it. If there are
characters which, as referred to the subject, afford purely negative
judgments; — this is a proof that we Iiave not a proper comprehen-
sion of the notion, and have only obtained a precursory definition
of it, enclosing it within only negative boundaries. For a definition
wiiich contains only negative attributions, affords merely an empty
notion, — a notion which is to be called a nothing; for, as some
think, it must at least possess one positive character, and its defini-
tion cannot, tlierefore, be made up exclusively of negative attri-
butes. If, however, a notion stands opposed to another which has
already been declared by positive characters, it may be defined by
negative characters, — provided always that the genus is positively
determined. Thus Cuvier and other naturalists define a certain or-
der of animals by the negation of a spine or back-bone, — the inver-
tebrata as opposed to the vertebrata / and many such definitions
occur in Natural History.
For a similar reason, the definition must not consist of divisive or
disjunctive attributions. The end of a definition is a clear and dis-
tinct knowledge. But to say that a thing is this or that or the
other, affords us either no knowledge at all, or at best only a vague
and obscure knowledge. If the disjunction be contradictoiy, its
enunciation is, in fact, tantamount to zero ; for to say that a thing
either is or is not so and so, is to tell us that of which we required
no assertion to assure us. But a definition by disparate alternatives
1 Cf. Krug, Logilc, § 123. Anna, i — Ed.
44
346 LOGIC. Lect. XXIV.
is, though it may vaguely circumscribe a notion, only to be consid-
ered as a prelusory definition, and as the mark of an incipient and
yet imperfect knowledge. We must not, however, confound de-
finitions by divisive attributes with propositions expressive of a
division.
The Third Rule is, — " The definition should not be tautological ;
that is, what is defined should not be defined by
^ ^ " , " *! , itself. This vice is called defining in a circle.
Defining in a circle. . ^ "
This rule may be violated either immediately or
mediately. The definition, — Law is a lawful command, — is an
example of the immediate circle. A mediate circle requires, at
least, two correlative definitions, a principal and a subsidiary. For
example, — Law is the expressed xcish of a ruler, and a rtder is one
who establishes laics. The circle, wliether immediate or mediate, is
manifest or occult according as the thing defined is repeated in the
same terms, or with other synonymous words. In the previous ex-
ample it was manifest. In the following it is concealed : — Grati-
tude is a virtue of acknnioledgm,ent, — Might is the competence to do
or not to do. Such declarations may, however, be allowed to stand
as prelusory or nominal definitions. Concealed circular definitions
are of very frequent occurrence, when they are at the same time
mediate or remote ; for we are very apt to allow ourselves to be
deceived by the difference of expression, and fimcy that we have
declared a notion when we have only changed the language. We
ought, therefore, to be strictly on our guard against this besetting
vice. The ancients called the circular definition also by the name
of DiaUdon, as in this case we declare the definUum and the
defyiiens reciprocally by each other {hC aKX.r,\<jiv)} In probation
there is a similar vice which bears the same names." ^ We may, I
think, call them by the homely English appellation of the Seesaw.
The Fourth Rule is, — ".That the definition should be precise;
that is, contain nothing unessential, nothing su-
FonrthRuIe. „ t^ . , . .,
perfluous. Unessential or contmgent attributes
are not sufficiently characteristic, and as they are now present, now
absent, and may likewise be met with in other things which are not
comprehended under the notion to be defined, they, consequently,
if admitted into a definition, render it sometimes too wide, some-
times too narrow. The well-known Platonic definition, — '■Man is
a two-legged animal without feathers,' — could, as containing only
unessential characters, be easily refuted, as was done by a plucked
1 Compare Sextns Empiricus, Pt/rrk. Hyp., » Krug, Logik, { 123- Anm. 3. — Ed.
J 169, ii. 68. — Ed.
Lect. XXIV. LOGIC. 347
cock.^ And when a definition is not wholly made np of such attri-
butes, and when, in consequence of their intermixture with essen-
tial characters, the definition does not absolutely fail, still there is a
sin committed against logical purity or precision, in assuming into
the declaration qualities such as do not determinately designate what
is defined. On the same principle, all derivative characters ought
to be excluded from the definition ; for although they may neces-
sarily belong to the thing defined, still they overlay the declaration
with superfluous accessories, inasmuch as such characters do not
designate the original essence of the thing, but are a mere conse-
quence thereof. This fault is committed in the following defini-
tion : — The Circle is a curved line returning upon itself, the paints
of which are at an equal distance from the central point. Hero
l)recision is violated, though the definition be otherwise correct. For
that every line returning upon itself is curved, and that the point
from which all the paits of the line are equidistant is the central
point, — these are mere consequences of the returning on itself, and
of the equidistance. Derivative characters are thus mixed up witli
the original, and the definition, therefore, is not j^recise." ^
The Fifth rule is, — "That the definition should be perspicuous,
that is, couched in terms intelligible, not figura-
Fifth Kule. . ' ,. _, r ^ . . ° ,
tive, and compendious.. Ihat definitions ought
to bo perspicuous, is self-evident. For why do we declare or define
at air? The perspicuity of the definition depends, in the first place,
on the intelligible character of the language, and
III Older to perspi- i\i[^ again depends on the employment of words
cuity in Definition, • ^i, • • j t • 'u ^' mi
, .,., , ' m their received or ordinary signification. 1 he
1. J he language must _ .
be intelligible. meaning of words, both separate and in con-
junction, is already determined by conventional
usage ; when, therefore, we bear or read these, we naturally asso-
ciate with them their ordinary meaning. Misconceptions of every
kind must, therefore, arise from a deviation from the accustomed
usage ; and though the definition, in the sense of the definer, may
be correct, still false conceptions are almost inevitable for others.
If such a deviation becomes necessary, in consequence of the com-
mon meaning attached to certain words not corresponding to cer-
tain notions, there ought at least to be appended a couiment
or nominal definition, by which we shall be warned that such
words are used in an acceptation wider or more restricted than they
obtain in ordinary usage. But, in the second place, words ought
not only to be used in their usual signification, — that signification,
1 Diog. Laert , vi. 40. — Ed. 9 Krng, Logik, 4 123. Anm. 2. — Ed.
348 LOGIC. Lect. XXIV.
if the definition be perspicuous, must not be figurative but proper.
Tropes and figures are logical hieroglyphics, and themselves re-
quire a declaration. They do not indicate tlie
2. The meaniDg must t^ing itself, but Only Something similar."^ Such,
be not figurative, but « , .^ -i r- ■ ■ i r-
tor example, are the definitions we have of
proper. i^ '
Logic as the Pharus Intellectus^ — the Light-
house of the Understanding, — the Cynosura Veritatis, — the Cy-
nosure of Truth, — the Medicina Mentis, — the Physic of the
Mind, etc.^
"However, many expressions, originally metaphorical (such as
conception, imagination, comprehension, representation, etc. etc.),
have by usage been long since reduced from figurative to proper
terms, so that we may employ these in definitions without scruple,
— nay frequently must, as there are no others to be found.
" In the third place, the perspicuity of a definition depends upon
its brevity. A long definition is not only bur-
3. The definition , . ,-, i i-i • i
must be brief. thensome to the memory, but likewise to the
understanding, which ought to comprehend it at
a single jet. Brevity ought not, however, to be purchased at the
expense of perspicuity or completeness."^
"The rules hitherto considered proximately relate to Definitions
in the stricter sense. In reference to the other
The other kinds of kinds of Declaration, there are certain modifica-
Deciaration. ^j^^^g ^^^ exceptions admitted. These Dilucida-
Dilucidations orEx- . .
plications. tions or Explications, as they make no pretence
to logical perfection, and are only subsidiary to
the discovery of more perfect definitions, are not to be very rigidly
dealt with. They are useful, provided they contain even a single
true character by which we are conducted to the apprehension of
others. They may, therefore, be sometimes too wide, sometimes too
narrow. A contingent and derivative character may be also useful
for the discovery of the essential and original.
Circular Definitions. t-< d~i- ^ t^ i' '^- ^ \ i
Even Circular Dennitions are not here abso-
lutely to be condemned, if thereby the language is rendered simpler
and clearer. Figurative Expressions are like-
ligurative Expres- ^j^^, j,j ^^^^^ j^^^ f^^^^. ^^^^^ j^ definitions
liions. . • 1 1
])roper, inasmuch as such expressions, by the
analogies they suggest, contribute always something to the illustra-
tion of the notion.
" In regard to Descriptions, these must be adequate, and no circle
1 Krug, Logik, { 123. Anm. 4. — Ed . S S«e above, p. 26. — Ed.
3 Krug, »6k/. — Ed.
Lect. XXIV. LOGIC. 349
is permitted in them. But they need not be so precise as to ad-
mit of no derivative or contingent characters.
For descriptions ought to enumerate the char-
acters of a thing as fully as possible ; and, consequently, they cannot
be so brief as definitions. They cannot, however, exceed a certain
measure in point of length."'
1 Krag, Logik, i 123. Anm. 5. ~ Ed.
LECTURE XXV.
METHODOLOGY.
SECTION II. — LOGICAL METHODOLOGY.
IL — DOCTRINE OF DIVISION.
I NOW proceed to the Second Chapter of Logical Methodology, —
the Doctrine of Division, — the doctrine which
affords us the rules of that branch of Method,
by which we render our knowledge more distinct and exhaustive.
I sliall preface the subject of Logical Division by some observations
on Division in general.
"Under Division (divisio, Siat/ieo-is) we understand in general the
sundering of the whole into its parts.* The
Division in general. , . . .... .,..,,. n -• i - t . t ■,
object which is divided is called the divided
whole {totxim divisiim), and this whole must be a connected many,
— a connected multiplicity, for otherwise no division would be pos-
sible. The divided whole must comprise at least one character,
affording the condition of a certain possible splitting of the object.,
or through which a certain opposition of the object becomes recog-
nized ; and this character must be an essential attribute of the
object, if the division be not aimless and without utility. This
point of view, from which alone the division is possible, is called
the j!9rt/?c?/:)^e of the division {principium sive fundaraentum divisi-
onis) ; and the parts which, by the distraction of the whole, come
into view, are called the divisive members (membra dividentia).
When a whole is divided into its ])arts, these parts may, either all
or some, be themselves still connected multiplicities; and if these
are again divided, there results a sid)division {subdivisio), the sev-
eral parts of which are called the subdivisive members (membra
std)dividentia). One and the same object may, likewise, be differ-
ently divided from different points of view, whereby condivisions
1 [Oo DIrision and its vnrioue kinds, see Ammouius, De Quinque Voeibtu, f. 6*, AM. IMS.]
Lect. XXV. LOGIC. 851
{condivisiones) nrise, which, taken together, arc all reciprocally
coordinatetl. If a division has only two members, it is called a
dichotomy {dichotomia) ; if three, a trichotomy (trichotomia) ; if
four, a tetrachotom,y ; if many, 2l polytomy, etc.
"Division, as a genus, is divided into two species, according to
the different kind of whole which it sunders into
Division of two 8p€- parts.^ These parts are either coi)tained in the
^"'^' , r^- • • divided whole, or they are contained under it.
Logical Division. ' •'
In the former case the division is called a parti-
tion {partitio^airapiSix-qaL^)^ in the latter, it is named a logical divi-
sion? Partition finds an application only when the object to^ be
divided is a whole compounded of parts, — consequently, where
the notion of the object is a complex one; Logical Division, on the
other hand, finds its application only where the notion contains a
plurality pf characters under it, and where, consequently, the notion
is a universal one. The simple notion is thus the limit of Parti-
tion ; and the individual or singular is thus the limit of Division.
Partition is divided into ^physical or real, when
Partition cither Eoal ^, ^ ^ ii i ^ i j? i
the parts can actually be separated irom each
other; and into a metaphysical or ideal, when
the parts can only be sundered by Abstraction.* It may be applied
in order to attain to a clear knowledge of .the whole, or to a clear
knowledge of the parts. In the former case, the parts are given
and the whole is sought; in the latter, the whole is given and the
parts are sought. If the whole be given and the parts sought out,
the object is first of all separated into its proximate, and, thereafter,
into its remoter parts, until either any further partition is impossible,
1 [On various kinds of Wlioles, see Cara- By Division, triangle is distinguished, 1°,
muel, Rationaiis et Healis Pkilosopliia, L. iv. Into the two species of rectilinear and curvi-
sect. iii. disp. iv. p. 277,] [and above, Lectures linear. '2°, Both of these are again subdi-
cn Metaphysics, -p. f^l; Lectures on Logic, p. vided (A) by reference to the sides, (B) by
142. — Ed.] reference to the angles. By reference to the
^ ' ATraplb/i7](Tis is properly a rhetorical sides, triangles are divided into the three
term, and signifies tlie division of a subject species of equilateral, isosceles, and scalene,
into successive heads, first, second, etc. See (The dichotomic division would, however, be
Uermogenes, Ilepl iSeoi/'. Rhetores Gr^ci, i. p. here more proper.) By reference to the an-
104, cd. Aid. — Ed. gles, they are divided into the three species of
3 [See Keckermaun, Systema Logicce, L. i. rectangular, t e. triangle which has one of
0. 3. Opera, t. i. p. 6G7. Drobiscli, New Bar- its angles right; into amblygon, or triangle
stellung der Logik, § 112. Krug, Logik, § 124. which has one of its angles obtuse; and into
Anm. 2 ] oxygon, /. e. triangle which has its three
•* By I'artition, triangle may be distinguished, angles acute.
1°, Into a certain portion of space included By Definition, triangle is distinguislied into
within certain boundaries; 2°, Into sides and figure of three sides, equal to triangular
angles; 3°, Into two triangles, or into a tra- figure; that is, into figure, the proximate
pezium and a triangle. The first two parti- genus, and trilateral or three-sided, the differ-
tions are ideal, they cannot be actually ac- ential quality,
complished. The last is real, it may.
352 LOGIC. Lect. XXV.
or the partition has attained its end. To this there is, however, re-
quired an accurate knowledge of the object, of its parts proximate
and remote, and of the connection of these parts together, as con-
stituting the whole. We must, likewise, take heed whether the
partition be not determined from some particular point of view, in
consequence of which the notions of more proximate and more
remote may be very vague and undetermined. If the parts be
given, and from them the whole sought out, this is accomplished
when we have discovered the order, — the arrangement, of the
parts; and this again is discovered when the principle of division
is discovered ; and of this we must obtain a knowledge, either from
the general nature of the thing, or from the particular end we have
in view. If, for example, a multitude of books, of every various
kind, are arranged into the whole of a well-ordered library, — in
this case the greater or lesser similarity of subject will afford, either
exclusively or mainly, the principle of division. It happens, how-
ever, not unfrcquently, that the parts are ordered or arranged
according to different rules, and by them connected into a whole ;
an<l, in this case, as the different rules of the arrangement cannot
together and at once accomplish this, it is proper that the less
important arrangement should yield to the more important ; as, for
example, in the ordering of a library, when, besides the contents
of the books, we take into account their language, size, antiquity,
binding, etc."'
I now proceed to Logical Division, on which I give you the
following pai'agraph :
% LXXXV. The Distinctness and Completeness of our
^ knowledge is obtained by that logical pro-
par LXXXV. Logi- ^^^^ which is tcrmcd Division (divisio,
oal Division. '' '
8taipc<ns). Division supposes the knowl-
edge of the whole to be given through a foregone process of
Definition or Declaration ; and proposes to discover the parts
of this whole which are found and determined not by the
development of the Comprehension, but by the development
of the Extension. As Logical Definition, therefore, proposes
to render the characters contained in an object, that is, the
comprehension of a reality or notion, Clear ; Logical Division
proposes to render the characters contained under an object,
that is, the extension of a notion. Distinct and Exhaustive.
Division is, therefore, the evolution of the extension of a
1 Esser, 1.0^ lit, H 134, 135, p. 261-«4. — Ed.
Lect. XXV. LOGIC. 3,')8
notion : .and it is expressed in a disjunctive proposition, of
wlucli the notion (li\ iiled constitutes tlie subject, and tlio
notions coutaine(| under it, tlie jiredicate. It is, tliereforo,
regulated by tlie law Avhicli o()\ei-iis Disjunctive Judgnient.s,
(the Pi'inciple of Kxchnled Middk'), aUliough it is usually
expresse(l in the I'oiMii of a Copulative ( 'atcgoi'ical Judgment.
The I'ules by which this ])rocess is I'cgulateil are seven :
1°. iMery I)i\ision shoidd be governed by some pi'inciple,
{Dirixlo itc. (u(r<'(it funJjntn nfa).
2°. Every J)ivision should be governed by oidy a singl(>
principle.
o*. Tlie piMii('i]ile of I)i\i>ioii should be an actual ;in(l essen-
tial character of the <livided notion, and the division, therefore,
neitlier complex nor without a juirpose.
4°. Xo di^•iding member of the predicate must l)y itself
exhaust the subject.
5°. The dividing iiu'inbers, taken together, must exhaust, but
only exhaust, the subject.
0°. The di\isive members must be reciprocal! v exclusive.
7°. The di\'isioiis must ]>roceed continuouslv from immediat(!
to mediate d'iiei'eiices (/Jin'sio ne Jidt per aaltinn).
In this paragraph are contained, first, the general Princi]»les of
Logical Division, and, secondly, the l^aws by
which it IS governed. 1 shall now illustrate
these in detail.
In the iirst place, it is stated that "the distinctness and complete-
ness of our knowledge is obtaiiie<l by that logical ])rocess which is
termed Division [divisio, 8t(u'/jerjt?). Di\ ision supposes the knowl-
edge of the whole to be given through a tbregone jirocess of defini-
tion, and projioscs to discover the parts of this whole which art;
found and determined not by the development ol' the comjirehen-
sion, but by tlie develojiment of the extension. As logical defini-
tion, therefore, proposes to render the characters contained in a
notion, that is, its comprehension, clear; logical division pr(>poses
to render the characters contained under an object, that is, the
extension of a notion, distinct. Division is, therefore, the evolution
of the extension of a notion, and it is expresse<l in a disjunctive
proi)osition, of which the notion divided constitutes the subject,
and the notions contained under it, the predicate. It is, therefore,
regulated by the law which go\erns disjunctive judgments (tho
princi])le of excluded middle), although it be usually expressed in
the form of a copulative categorical judgment."
45
>354 1.0 G I C. Lect. XXV.
The special virtue, the particular element, of perfect thinking,
which Division enables us to acquire, is Dis-
End of Division is tinctucss, but, at the same time, it is evident
Distinctness, which in- ... ,.,,.., ,
voives Completeness. ^^^^ ^^ Cannot accomplish this without render,
ing our thinking more complete. This, how-
ever, is only a secondary and collateral result ; for the problem
which division proximately and principally proposes to solve is, —
to afford us a distinct consciousness of the extension of a given
notion, through a complete or exhaustive series of subordinate or
coordinate notions, Tiiis utility of Division, in rendering our
knowledge more complete, is, I find, stated by Aristotle,' though
it has been -overlooked by subsequent logicians. He observes that
it is only by a regular division that we can be assured that nothing
has been omitted in the definition of a thing.
"As it is by means of division that we discover what are the
characters contained under the notion of an
As many kinds of • /• n
Division possible as objcct, it follows that there must be as many
there are characters kinds of division possiblc as there are chai-ac-
aflbrdinfi a Principle ^q^^ contained Under the notion of an object,
which may afford the principle of a different
division. If the characters which afford the principle of a division
are only external and contingent, there is a division in the wider
sense ; if, again, they are internal and constant, there is a division
in the stricter sense ; if, finally, they are not only internal but also
essential and' original, there is a division in the strictest sense.
From the very conception of logical division, it
A universal notion j^ manifest that it can only be applied where
Lo ica" Division ^'^^ objcct to be divided is a universal notion,
and that it is wholly inapplicable to an individ-
ual ; for as the individual contains nothing under it, consequently it
is not susceptible of an ulterior division. The general problem of
which division affords the solution is, — To find
General problem of ^^^ subordinate genera and species, the higher
Division. ^^ . , ^ ^ =*
or generic notion being given. The higher
notion is always something abstracted, — something generalized
from the lower notions, with which it agrees, inasmuch as it con-
tains all that is common to these inferior concepts, and from which
it differs, inasmuch as they contain a greater number of determin-
ing charactei-s. There thus subsists an internal connection between
the higher and the lower concepts, and there is thus afforded a tran-
sition from the superior notion to the subordinate, and, conse-
quently, an evolution of the lower notions from the higher.
1 Anat. Pott., L. ii. 0. 1&
Lect. XXV. LOGIC. 366
order to discover the inferior genera and species, we have only to
discover those characters which afford the proximate determina-
tions, by which the spliere or extension of the higher notion is
circumscribed. But to find what characters are wanted for the
thoroug])-g()ing determination of a higher notion, we must pre-
viously know what characters the higher notion actually contains,
and this knowledge is only attainable by an analysis, — a sundering
of tlie higher notion itself In doing this, the several characters
must be separately drawn forth and considered ; and in regard to
each, we must ascertain how far it must still be left undetermined,
and how fiir it is capable of opposite determinations. But whether
a character be still undetermined, and of what opposite determina-
tions it is capable, — on these points it is impossible to decide a
priori^ but only a 2^osteriori, through a knowledge of this particular
character and its relations to other notions. And the accomplish-
ment of this is rendered easier by two circumstances; — the one,
that the generic notion is never altogether abstract, but always
realized and held fast by some concrete form of imagination; — the
other, that, in general, we are more or less acquainted with a greater
or a smaller number of special notions, in which the generic notion
is comprehended, and these are able to lead us either mediately or
immediately to other subordinate concepts.
" But the determinations or constituent characters of a notion
Avhich we seek out, must 'not only be completely, but also precisely,
opposed. Completely, inasmuch as all the species subordinate to
the notions ougfit to be discovered ; and precisely, inasmuch as
whatever is not a subordinate species, ought to be absolutely
excluded from the notion of the genus.
"In regard to the completeness of the opposition, it is not, how-
ever, required that the notion should be determined through every
possible contradictory opposition ; for those at least ought to be
omitted, concerning whose existence or non-existence the notion
itself decides. In regard to the opposition itself, it is not required
that the division should be carried through by contradictory oppo-
sitions. The only opposition necessary is the reciprocal exclusion
of the inferior notions into which the higher notion is divided."'
In a mere logical relation, indeed, as we know nothing of the nature
of a thing more than that a certain character either does or does
not belong to it, a strictly logical division can only consist of two
contradictory members, for example, — that angles are either ri(/ht
or not riffht, — that men are either white or 7iot lohite. But looking
to the real nature of the thing known, either a priori or a posteri-
1 Esser, Logik, 5 136. — Ed.
366 LOGIC. Lect. XXVv
on, the division may be not only dichotomous but polytomous, as
for example, — angles are rights or acute, or obtuse ; men are tohite^
or blade, or copper-colored, or olive-colored, etc.
We now come, in the second place, to the
Rales of Logical Di- , t ^ ^ j ^ x ■ i ta- • •
rules dictated tor Losrical Division.
vision. _ ° _
These Rnles spring either, 1°, From the Prin-
ciple of Division ; or, 2°, From the Relations of the Dividing Mem-
bers to the Divided Whole; or, 3°, From the Relations of the
several Dividing Members to each other; or, 4°, From the relations
of the Divisions to the Subdivisions.
The first of these heads — the Principle of Division — compre-
hends the three first rules. Of these the firet is
ose springing, . self-evident, — There must be some principle,
From the rnuciple of ' ... i r '
Divwion. First Kuie. somc reason, for every division ; for otherwise
there would be no division determined, no divi-
sion carried into effect.
In regard to the second rule, — That every division should have
only a single principle, — the propriety of this is
likewise stifiiciently apparent. In every division
we should depart from a definite thought, which has reference either
to the notion as a unity, or to some single character. On the con-
trary, if we do not do this, but carry on the process by different
principles, the series of notions in which the division is realized is
not orderly and homogeneous, but heterogeneous and perplexed.
The Third rule, — That the principle of div*ision should be an
actual and essential charact<?r of the divided
Third. . . , .^ ^ ,
notion, — IS not Ies3 manitest. " As the ground
of division is that \vj)ich principally regulates the correctness of the
whole process, that is, the completenesj* and opposition of the divi-
sion, — it follows that this ground niuH be of notoriety and impor-
tance, and accommodated to the end for the sake of which the
division is instituted. Those characters of an object are best
adapted for a division, whose own determinations exert the great-
est influence on the determinations of otlier characters, and, con-
sequently, on tliose of the notion itself; but suchCare inanift-stly not
the external and contingent, but the internal and essential, charao-
ters, and, of these, those have the preeminence through whose deter-
mination the greater number of otheis are determined, or, what is
the same thing, from which, as fundamental and original attributes,
the greater number of the others arc derived. The choice of char-
acter is, however, for the most part, regulated by some particular
end; so that, under certain circumstances, external and contingent
characters may obtain a preponderant importance. Such ends can
Lkct. XXV. LOGIC.
not, however, be enumerated. The character afFording the principle
of division must likewise be capable of being clearly and definitely
brought out ; for unless this be possible, we can have no distinct
consciousness of the completeness and contrast of the determination
of which it is susceptible. We ought, therefore, always to select
those characters for principles of division, which are capable of a
clear and distinct recognition."'
The second part of the rule, — That the division be not, therefore,
too complex, and without a purpose, — is a corollary of the fii*st.
" In dividing, we may go on to infinity. For while, as was formerly
shown, there is, in the series of higher and lower notions, no one
which can be conceived as absolutely the lowest ; so in subdividing,
there is no necessary limit to the process. In like manner, the
coordinations may be extended ad infinitum. For it is impossible
to exhaust all the possible relations of notions, and each of these
may be employed as the principle of a new division. Thus we can
divide men by relation to their age, to their sex, to their color, to
their stature, to their knowledge, to their riches, to their rank, to
their manner of life, to their education, to their costume, etc., etc.
It would, however, be ridiculous, and render the divisions wholly
useless, if we multiplied them in this fashion without end. We,
therefore, intentionally restrict them, that is, we make them com-
paratively limited, inasmuch as we only give them that completeness
which is conducive to a -certain end. In this manner, divisions
become relatively useful, or acquire the virtue of adaptation. In
the selection of a principle of division, we must take heed whether
it be fertile and pertinent. A ground of division is fertile, when it
affords a division out of which again other important consequences
may be drawn ; it is pertinent, when these consequences have a
proximate relation to the end, on account of which we were origi-
nally induced to develop the extension of a concept, A principle
of division may, therefore, be useful with one intent, and useless
with another. Soldiers^ for example, may be conveniently divided
into cavalry and infantry^ as this distinction has an important influ-
ence on their determination as soldiers. But in considering man in
general and his relations, it would be ludicrous to divide men into
foot and horsemen ; while, on the contrary, their division would be
here appropriate according to principles which in the former case
would have been absurd. Seneca^ says well, — 'Quicquid in majus
crevit facilius agnoscitur, si discessit in partes; quas innumerabilcH
esse ct parvas non oportet. Idem enim vitii habet nimia, quod null.i
1 EBSer, Logik, } 137. — Ed- 2 Epist., 90.
358 LOGIC. Lect. XXV.
divisio. Simile confuso est, quicquid usque in pulverem sectum
est.'"^
Under the second head, that is, as springing from the relations of
the Dividing Members to the Divided Wholes,
II. From the reia- ^jj^^.g ^re included the fourth and fifth laws.
tions of the Dividing ,, a j.\ • t i • • i • i .
Members to the Divid- "^sthe notion and the notions into which it
ed Wholes. Fourth. is divided Stand to each other in the relation of
whole and parts, and as the whole is greater
than the part, the fourth rule is manifestly necessary, viz.. That no
dividing member of the predicate must by itself exhaust the sub-
ject. When this occurs, the division is vicious, or, more properly*
there is no division. Thus the division of man into rational ani-
mals and uncultivated nations^ would be a violation of this law.
" On the other hand, as the notions into which a notion is divided,
stand to each other in the relation of constitut-
Fifth.
mg parts to a constituted whole, and as the
whole is only the sum of all the parts, the necessity of the fifth rule
is manifest, — That the dividing members of the predicate, taken
together, must exhaust the subject. For if this does not take place,
then the division of the principal notion has been only partial and
imperfect. We transgress this law, in the first place, when we leave
out one or more membci's of division ; as for example. — Tlie actions
of men are either good or had, — for to these we should have adde'd
or indifferent. And in tho second place, we transgress it when wc
coordinate a subdivision with a division ; as for example, — Philos-
ophy is either theoretical philosophy or moral philosophy : here the
proper opposition would have been theoretical philosophy and jororc-
ticol philosophy r^ On the other hand, the dividing members, taken
together, must not do more than exhaust the subject. The defini-
tion of the whole must apply to every one of its parts, but this con-
dition is not fulfilled if there be a dividing member too much, that
is, if there be a notion brought :is a dividing member, which, Iiow-
ever, does not stand in subordination to the divided whole. For
example, — Mathematical figures are either solids or surfaces [or
lines or 2)oints\ Here the last two members {lines and points) are
redundant and erroneous, for lines and points, though the elements
of mathematical figures, are not themselves figures.
- Under the third head, as springing from the relations of the sev-
eral Dividing Members to Each Other, there is a single law, — the
sixth, — which enjoins, — That the dividing members be recipro-
cally exclusive.
1 Knig, Logik, i 126. Anm. 4. — Ed. S Esaer, Lagik, ) 187. — £d.
Lkct. XXV. LOGIC. 359
" As a division does not present the same but the different deter-
minations of a single notion (for otherwise one
III. From the reia- and the same determination would be presented
tions of the several ^^^j^.^) tj^^ dividing members must be so consti-
Dividing Members to ' ^ ,, . . ,
Kaoh Other. Sixth. tuted that they are not mutually comcident, so
that they either in whole or in part contain
each other. This law is violated when, in the first place, a subdi-
vision is placed above a division, as, — Philosophy is either theoret-
ical philosophy, or moral philosojihy, or 2iractical philosophy ; here
moral philosophy falls into practical philosophy as a subordinate
part; or when, in the second place, the same thing is divided in
different points of view, as, — Human actions are either necessary^
or free, or useful, or detrimentaV ^
Under the fourth and last head, as arising from the relations of
the Divisions to the Subdivisions, there is con-
IV. From the reia- taiued One law, the seventh, which prescribes, —
tions of the Divisions rj.}^^^ ^^^ divisions proceed continuously from
to the Subdivisions. . . , -r\- • •
Seventh. immediate to mediate differences {Utvtsto ne
fat per salttan vel hiatum).
" As divisions originate in the character of a notion, capable of
an opposite determination, receiving this determination, and as the
subdivisions originate in these opposite determinations being them-
selves again capable of opposite determinations, in which gradual
descent we may proceed indefinitely onwards, — from this it is evi-
dent, that the divisions should, as far as possible, be continuous, that
is, the notion must first be divided into its proximate, and then into
its remoter parts, and this without overleaping any one part ; or in
other words, each part must be immediately subordinated to its
whole." ^ Thus, when some of the ancientsdivided j(?Ai7osq/9Ay into
rational, and natural, and moral, the first and second members are
merely subdivisions of theoretical philosophy, to which m,oral as
practical philosophy is opposed. Sometimes, however, such a
spring — such a saltus — is, for the sake of brevity, allowed ; but
this only under the express condition, that the omitted members
are interpolated in thought. Thus, many mathematicians say, angles
are either right, or acute, or obtuse, although, if the division w^ere
continuous, witl)out hiatus, it would run, angles are either righi
or oblique; and the oblique, again, either acuta or obtuse.
1 Esser, Logik, § 137- — Ed. 2 Esser, Logile, § 137. — Ed.
LECTURE XXVI.
METHODOLOOY.
SECTION II. — LOGICAL METHODOLOGY.
in— DOCTRINE OF PROBATION.
We now proceed to the Third Part of Pure Methodology, that
which guides us to the third character or virtue
of Perfect Thinking, — the Concatenation of
Thought; — I mean Probation, or the Leading of Proof. I com-
mence with the following paragraph.
% LXXXVI. When there are propositions or judgments
which are not intuitively manifest, and the
Par. LXXXVI. Pro- ^,.^^1^ ^f ^hich Is not admitted, then their
bation.-iti Nature ,,.,,»
and Elements. Validity can Only be established when we
evolve it, as an inference, from one or more
judgments or propositions. This is called frohation, Proving,
or the Leading of Proof (probatio, argitmentatio, or demoiX'
stratio^ in its wider sense). A Probation is thus a series of
thoughts, in which a plurality of different judgments stand to
each other, in respect of their validity, in the dependence of
determining and determined, or of antecedents and conse-
quents. In every Probation there are three things to be dis-
tinguished,— 1°. The Judgment to be proved, (thesis) ; 2°. The
Ground or Principle of Proof, (argumentum) ; and, 3°. Tl>e
Cogency of this principle to necessitate the connection of
antecedents and consequents (vis demonstrationis or nervus
probandi). From the nature of Pivbation, it is evident that
Probation without inference is impossible ; and that the Thesis
to be proved aird Principles of Proof stand to each other as
conclusion and premises, with this difference, that, in Proba-
tion, there is a judgment (the thesis) expressly supposed,
which, in the Syllogism, is not, ?it least necessarily, the case.'
1 Esscr, Logik, S 138. Cf. Krug, Logik, S 127. — Ed. [Cf. Richter, Vber den Gegenstand w
fttH Vn{fang der Logik, iS2 el seq.]
Lkct. XXVI. LOGIC. 361
In regard to the terms here employed, it is to be noticed that the
term argumentation {argumentatio) is applied
Explication. not only to a reasoning of many syllogisms, but
Terms employed. likewise to a reasoning of one. The term argu-
Argumentation. . ti
Argument. mcnt [argumentum) in like manner is employed
not only for the ground of a consecutive reason-
ing, but for the middle term of a single syllogism. But it is, more-
•over, vulgarly employed for the whole process of argumentation.^
The term demonstration (demonstratio) is used in a looser and
in a stricter signification. In the former sense,
DemonPtration. . . . , '
It IS equivalent to probation, or argumentation
in general; in the latter, to necessary probation, or argumentation
from intuitive principles.
The expression leading q/'j!?roo/' might, perhaps, be translated by
the term deduction, but then this term must
lugo roo o 1^^ ^^ such a latitude as to include induction, to
two sorts.
which it is commonly opposed ; for Probation
may be either a process of Deduction, that is, the leading of proof
out of one higher or more general proposition, or a process of
Induction, that is, the leading of proof out of a plurality of lower
or less general judgments.
To prove, is to evince the truth of a proposition not admitted to
be true, from other propositions the truth of
I'robalion in general. i • i • i i i t i i x
which IS already established. In every proba-
tion there are three things to be distinguished : — 1°. The Proposi-
tion to be proved, — the Thesis ; 2°. The Grounds or Principle of
Proof, — the Argument; and, 3°. The Degree of Cogency with
which the thesis is infeiTed by the argumentum or argumenta, ■ —
the vis or nervus probandi. All probation is thus syllogistic ; but
all syllogism is not probative. The peculiarity
ow ismguisie ^^ probation consists in this, — that it expressly
from Syllogism. ^ . ' I .
supposes a certain given proposition, a certain
thesis, to be true ; to the establishment of this proposition the
proof is relative ; this proposition constitutes the conclusion of the
syllogism, or series of syllogisms, of which the probation is made
up ; whereas, in the mere syllogistic process, this supposition is not
necessarily involved. It is also evident that the
Whereon depends logical Value of a probation depends, 1°. On the
tbe logical value of a j. ..t j? '^ • • i .,00/^
probation truth oi its principles or argumenta, z . Un
their connection with each other, and with the
thesis or proposition to be proved, and, 3°. On the logical foi*-
1 See above, p. 196. — Ed.
46
862 LOGIC. Lkct. XXVI.
mality of the inference of the thesis from its arguinenta. No prop-
osition can be for another the principle of proof, which is not itself
either immediately or mediately certain. A proposition is imme-
diately certain, or evident at first hand, when, by the very nature
of thought, we cannot but think it to be true, and when it, there-
fore, neither requires nor admits of proof. A proposition is medi-
ately certain, or evident at second hand, when it is not at once and
in itself thought as necessarily true, but when we are able to deduce*
it, with a consciousness of certainty, from a proposition which is
evident at first hand. The former of these certainties is called self-
evident, intuitive, original, jyrimary, ultimate, etc, and the latter,
demonstrative, derivative, secondary, etc.
According to this distinction, the Ground or Principle of Proof
is either an absolute or a relative. Absolute,
Ground of Proof ^yhen it is an intuitive; relative, when it is a
either Absolute or ., . • • rm x
g^j^y^g demonstrative proposition. Ihat every propo-
sition must ultimately rest on some intuitive
truth, on some judgment at first hand, is manifest, if the fact of
probation itself be admitted ; for otherwise the regress would
extend to infinity, and all probation, consequently, be impossible.
When, for example, in the series of grounds H, G,JF, E, D, C, B,
there is no ultimate or primary A, and when, consequently, every A
is only relatively, in respect of the consequent series, but not abso-
lutely and in itself, first; — in this case, no suflScient and satisfactory
probation is possible, for there always remains the question concern-
ing a still higher principle. But positively to show that such pri-
mary judgments arc actually given, is an exposition which, as
purely metaphysical, lies beyond the sphere of Logic.^
To the general form of a system of Proof belong the following
distinctions of propositions, to which I fomierly
Distinction of Prop- iiiioji-i_t • 11^
.... . - alluded,^ and which 1 may again recall to vour
ositions in respect of ' ./ o .
the general form of a remembrance. Propositions are either Theoret-
fystem of Proof. {f.Qi or Practical. Practical, when they enounce
Theoretical and ^j^^ j^ ^^^j^j^,^ j^ j^ possible to effectuate or
produce something; Theoretical, when they sim-
ply enunciate a truth, without respect to the way in which this may
be realized or produced.' A Theoretical proposition, if a primary
or intuitive principle, is styled an Axiom. Ex-
''"*'"' amples of this are given in the four Funda-
mental Laws of Logic, and in the mathematical common notions —
* Compare Esser, Logik, i 138 — Kd. 2 See above, p. 18". —Ed.
3 [Fries, Sn-Atm iltr Logik, i 73.]
Lect. XXVI. LOGIC. 363
The whole is greater than Us part, — J^ equals be added to equals,
the wholes are equal, etc. A Practical proposition, if a primary or
intuitive principle, is styled a Postulate. Thus
Geometry postulates the possibility of drawing
lines, — of producing them ad infinitum, of describing circles, etc.
A Theoretical proposition, if mediate and demonstrable, is called
a Theorem. This is laid down as a Thesis, —
Theorem. .
as a judgment to be proved, — and is proved
from intuitive principles, theoretical and practical. A Practical
proposition, if mediate and demonstrable, is
called a Problem,. In the probation, the Prob-
lem itself is firet enounced ; it is then shown in the solution how
that which is required is to be done, — is to be efiected ; and,
finally, in the proof, it is demonstrated that througli this procedure
the solution of the problem is obtained. For examj:)^, in the geo-
raeti'ical problem, — to describe an equilateral triangle on a given
straight line, — there this problem is first stated ; the solution then
shows that, with this given line as a semi-diameter, we are to
describe from each of its points of termination a circle ; the two
circles will intersect each other, and we are then, from the point
of intersection, to draw straight lines to each point of termination ;
this being done, the proof finally demonstrates that these circles
must intersect each other, that the drawn straight lines necessarily
constitute a triangle, and that this triangle is necessarily equilateral.
Corollaries or Consectaries are propositions which, as flowing
immediately as collateral results of others, re-
oro anes. m- quji-g jjq separate proof Empeiremata or Em-
peiremata. •* * *• ■* .
pirical Judgments are propositions, the validity
of which reposes upon observation and experience. Scholia or
Comments are propositions which serve only for
'^ ° '^' illustration. Lemmata or Sumptions are propo-
sitions, borrowed either from a different part of
the system we treat of, or from sciences other than that in which
we now employ them. Finally, Hypotheses are
Hypotheses. ^/ ,■•.,• -r.
propositions oi two dmerent significations, x* or,
in the first place, the name is sometimes given to the arbitrary
assumption or choice of one out of various means of accomplishing
an end ; when, for example, in the division of the periphery of the
circle, we select the division into 360 degrees, or when, in Arith-
metic, we select the decadic scheme of numeration. But, in the
second place, the name of hypothesis is more emphatically given to
provisory suppositions, which serve to explain the phenomena in so
far as observed, but which are only asserted to be true, if ultimately
364 LOGIC. LtCT. XXVI
confirmed by a complete induction. For example, the supposition
of the Copernican solar system in Astronomy,^
Now these various kinds of propositions are mutually concat-
enated into system by the Leading of Proof, — by Probation.
So much for the character of this process in general. The para-
graph already dictated contains a summary of the various particu-
lar characters by which Probations are distinguished. Before con-
sidering these in detail, I shall offer some preparatory observations.
"The differences of Probations are dependent partly on their
Matter, and partly on the Form in which they
The differences of j
,. u .. J, J are expressed.
FroDBtions depend '^
paiiiy on their Matter " I" respect of the former ground of differ-
and partly on their cnco, — the Matter, — Probations are distin-
*^"'^™" guished into Pure or a priori, and into Empir-
1. In respect of their ical Or a posteriori, according as they are
Matter, Probations founded on principles which we must recog-
are Pure and Empir- . ...
jg^j nize as true, as constitutmg the necessary con-
ditions of all experience, or which we do
2. In respect of their . , . , , .
y recognize as true, as particular results given
by certain applications of exfiorience. In re-
spect of the latter ground of difference, — the Form, — Probations
fall into various classes according to the difference of the form
itself, which is cither an External or an Internal.
" In relation to the Internal Form, probations are divided into
Direct or Ostensive and into Indirect or Apa-
(a) In relation to gogical, according as they are drawn from the
the Internal Form, ^^- .^^^jf ^^ f^.^^ j^^ opposite, in Other WOrds,
Probations are Direct " ..,_ ,.
or Ostensive and indi- according as the principles of probation are posi-
rect or Apagogicai. tivc or are negative." * Under the same relation
Synthetic or Pro- ^f Internal Form, they are also distinguished by
grossive and Analytic -, ^ ^i • i /• j ^i_-
or ReirreBsive. reierencc to their order oi procedure, — this
order being either Essential or Accidental. The
essential order of procedure regards the nature of the inference
itself^ as either from the whole to the part, or from the parts to the
whole. The former constitutes Deductive Probation, the latter
Inductive. The accidental order of procedure regards only our
point of departure in considering a probation. If, commencing
with the highest principle, we descend step by step to the conclu-
sion, the process is Synthetic or Progressive ; here the conclusion is
evolved out of the priuoiple. If^ again, starting from the conclu-
1 rrin, St/Ufm tttr Logik, { 7S. Kmg, L^ik, H VI, 68.]
2 £«scr, Logik, i Ul. — £0.
I
Lkct. XXVJ. logic. 365
sion, we ascend step by step to the highest principle, the process
is Analytic or Regressive ; here the principle is evolved out of the
conclusion.
In respect to the External Form, Probations are Simple or
Monosyllogistic, if they consist of a single
Prob tionr°re simT reasoning, Composite or Polysyllogistic if they
and Composite. consist of a plurality of reasonings. Under
Regular and irregu- the Same relation of external form, they ai-e
lar Perfect und im- ^j^^ divided into Regular and Irregular, into
p€ri6Ct« ,^
Perfect and Imperfect.
Another division of Probations is by reference to their Cogency,
or the Degree of Certainty with which their
their deg*i^'^o7cl- inference is drawn. But their cogency is of
g^ncy, Probations are various degrees, and this either objectively con-
Apodeictic and Proba- sidered, that is, as determined by the conditions
of the proof itself, or subjectively considered,
that is, by reference to those on whom the proof is calculated to
operate conviction. In the former, or objective relation, probations
are partly Apodeictic, or Demonstrative in the stricter sense of that
term, — when the certainty they necessitate is absolute and com-
plete, that is, when the opposite alternative involves a contradic-
tion ; partly Probable, — when they do not produce an invincible
assurance, but when the evidence in favor of the conclusion pre-
ponderates over that which is opposed to it. In the latter or sub-
jective relation, probations are either Universally
nirerga y an Valid, when they are calculated to operate con-
Particularly Valid. . . ♦' , ^
viction on all reasonabliB minds, or Particularly
Valid, when they are fitted to convince only certain individual
minda.
Par i-xxxvn ^ LXXXVII. Probations are divided by
Brob»tions, tiieir Di. reference to their Matter, to their Form,
'*'*°'*^' and to their Degree of Cogency.
In relation to their Mattel-, they are partly I*ure or a priori,
partly Empirical or a posteriori.
As to their Form, — this is either Internal or External. In
respect to their Internal Form, they arc, 1°, By j-eference to the
Manner of Inference, Direct or Ostensive (SetKriKat, ostensivm),
and Indirect or Apagogical {jyrohationes apayogicm reductiones
ad absurduvi) ; 2°, By reference to their Essential or Internal
Order of Procedure, they are either Deductive or Inductive,'
3°, By reference to their Accidental or External Order of Pro-
cedure, they are partly Synthetic or Progressive, partly Atia-
366 LOGIC. Lect. XXVI.
lytic or Hegressive. In respect to their External Form, tbey
are, 1°, Simple or Monosylloyistic, and Composite or P oly syllo-
gistic ; 2°, Perfect and Imperfect; 3°, Regular and Irregular.
In respect to their Degree ot Cogency, they are, 1°, As
objectively considered, either Apodeictic or Demonstrative in
the stricter signification of the term (aTrdScifcts, demonstrationes
stride dictce), or Probable (probationes sensu latiori) ; 2**, As
subjectively considered, they are either Universally Valid (/car
aXrj^eLav, secundum veritatem)^ or Particularly Valid (kot a»^
Bponrov, ad hominem,)}
To speak now of these distinctions in detail. In the first place,
" Probations," we have said, " in relation to their
T> K^J ' 1° T matter, are divided into Pure or a priori, arfd
Probations, 1. In re- ' ■» '
epect of their Matter, into Empirical or a posteriori. Pure or a priori
are Pure and Empiri- proofs are thosc that Tcst on principles which,
although rising into consciousness only on occa-
sion of some external or internal observation, of some act of expe-
rience, are still native, are still original, contributions of the mind
itself, and a contribution without which no act of experience
becomes possible. Proofs again are called Empirical or a pos-
teriori, if they rest on principles which are exclusively formed from
experience or observation, and whose validity is cognizable in no
other way than that of experience or observation. When the prin-
ciples of Probation are such as are not contingently given by expe-
rience, but spontaneously engendered by the mind itself, these
principles are always characterized by the qualities of necessity
and universality ; consequently, a proof supported by them is ele-
vated altogether above the possibility of doubt. When, on the
other hand, the Principles of Probation ai*e such as liave only the
guarantee of observation and experience for their truth, — (suppos-
ing even that the observation be correct and the experience stable
and constant), — these principles, and, consequently, the probation
founded on them, can pretend neither to necessity nor univei*sality ;
seeing that what produces the observation or experience has only a
relation to individual objects, and is only competent to inform us
of what now is, but not of what always is, of what necessarily must
be. Although, however, these empirical principles are impressed
with the character neither of necessity nor of universality, they
play a very important part in the theatre of human thought."'
1 Cf. KruB, Logik, H 128, 129, 130, 131, 132. Esser, Logik, s 139— Ed. [Cf. Degeranda
Vts Signts, t. iv. ch. 7, p. 234.] 3 Esser, Logik, ) 140.— £d.
Lect. XXVI. LOGIC. 367
This distinction of Proofe, by reference to the matter of our knowl-
edge, is one, indeed, which Logic does not take
This distinction of [^^q account, Logic, in fact, considers every
Probations not taken . „ -, ^ „ ^ i ^
^, _ . inierence ot a consequent irom an antecedent as
nito account by Logic. _ i
an inference a 2^^iori, supi^osing even that the
antecedents themselves are only of an empirical character. Thus
Ave may say, that, from the general relations of distance found to
hold between the planets, Kant and Olbers proved a priori that
between Mars and Jupiter a planetary body must exist, before
Ceres, Pallas, Juno, and Vesta, were actually discovered.^ Here,
however, tlie a priori principle is in reality only an empirical rule,
— only a generalization from experience. But with the manner
in which these empiiical rules — (Bacon would call them axi-
oms) — are themselves discovered or evolved — with this. Pure
Logic has no concern. This will fall to be considered in Modified
Logic, when we treat of the concrete Doctrine of Induction and
Analogy.
In the second place, "in respect of their Form, and that the
Internal, Probations are, as we said, first of all,
2. In respect of their divided into Direct or Ostensive, and into Indi-
anHndirect. ' "^^ ^®^* ^^* Apagogical. A proof is Direct or Os-
tensive, when it evinces the truth of a thesis
through positive principles, that is, immediately ; it is Indirect or
Apagogical, when it evinces the truth of a thesis through the false-
hood of its opposite, that is, mediately. The indirect is specially
Jled the apagogical {argumentatio apagogica sive deductio ad
impossibile), because it shows that something cannot be admitted,
since, if admitted, consequences would necessarily follow impossible
or absurd. The Indirect or Apagogical mode of proof is estab-
lished on the principle, that that must be con-
nncipeo n irec ceded to be true whose contradictory opposite
contains within itself a contradiction. This
principle manifestly rests, on the Law of Contradiction, and on
the Law of Excluded Middle ; for what involves a contradiction
it is impossible for us to think, and if a character must be denied
of an object, — and that it must be so denied the probation has to
show, — then the contradictory opposite of that character is of
necessity to be affirmed of that object. The Direct mode of proba-
tion has undoubtedly this advantage over the Indirect, — that it not
only furnishes the sought-for truth, but also truly develops its neces-
sary connection with its ultimate principles; whereas the Indirect
demonstrates only the. repugnance of some proposition with certain
1 See Kant's Vorlesungen iJfter Pkysische Geographie, 1802; Werke, vi. p. 449 — Ed.
LOGIC. Lect. XXVI.
truths, without, however, positively evincitig the truth of its oppo-
site, and thereby obtaining for it a full and satisfactory recognition.
It is, therefore, usually enaployed only to constrain a troublesome
opponent to silence, by a display of the absurdities which are
implied in, and which would flow out of, his assertions. Never-
theless, the indirect probation establishes the proposition to be
proved not less certainly than the direct; nay, it still more pre-
cisely excludes the supposition of the opposite alternative, and,
consequently, affords an intenser consciousness of necessity. We
ought, however, to be on our guard against the paralogisms to
which it is peculiarly exposed, by taking care — 1°, That the oppo-
sites are contradictory and not contrary; and 2°, That an absurdity
really is, and not merely appears to be. The differences of Apa-
gogical Probations correspond to the different
Diflerences of indi- kinds of propositions whlch may be indirectly
i*robation8 ^ ^ demonstrated ; and these are, in their widest
generality, either Categorical, or Hypothetical,
or Disjunctive. Is the thesis a categorical proposition ? Its con-
tradiclory opposite is supposed, and from this counter proposition
conclusions are deduced, until we obtain one of so absurd a charac-
ter, that we are able to argue back to the falsehood of the original
proposition itself. Again, is the thesis an hypothetical judgment?
The contradictory opposite of the consequent is assumed, and the
same process to the same end is performed as in the case of a cate-
gorical proposition. Finally, is the thesis a disjunctive proposi-
tion ? In that case, if its membra disjuncta are contradictorily
op})osed, we cannot, either directly or indirectly, prove it false as a
whole ; all that we can do being to show that one of these disjunct
members cannot be affirmed of the subject, from which it necessa-
rily follows that the other must." '
Under the Internal Form, Probations are, in the second place, in
respect of their Essential or Internal Order of
(b) Deductive an procedure, either Deductive or Inductive, accord-
Inductive. t ' -% '
ing as the thesis is proved by a process of reason-
ing descending from generals to particulars and individuals, or by a
process of reasoning ascending from individuals and particular to
generals. On this subject it is not necessary to say anything, as the
rules which govern the formal inference in these processes have
been already stated in the Doctrine of Syllogisms ; and the consid-
eration of Induction, as modified by the general conditions of the
matter to which it is applied, can only be treated of when, in the
sequel, we come to Modified or Concrete Methodology.
1 Esser, Logik, f 142. — Ed
Lect. XXVI. logic: 369
" Under the Internal Form, Probations are, however, in the third
place, in respect of their External or Accidental
aIeI tfj"*^^"*' ""'^ Order of procedure, Synthetic or Progressive,
and Analytic or Regressive. A probation is
called synthetic or progressive, when the conclusion is evolved out
of the principles, — analytic or regressive, when the principles are
evolved out of the conclusion. In the former case, the probation
goes from the subject to the predicate; in the latter case, from the
predicate to the subject. "Where the probation is complex, — if
synthetic, the conclusion of the preceding syllogism is the subsump-
tion of that following; if analytic, the conclusion of the preceding
syllogism is the sumption of that following. In respect of certainty,
both procedures are equal, and each has its peculiar advantages ; in
consequence of which the combination of these two modes of proof
is highly expedient. But the Analytic Procedure is often compe-
tent where the Synthetic is not; whereas the Synthetic is never
possible where the Analytic is not, and tliis is never possible whei-e
we have not a requisite stock of propositions already verified.
When the Probation is partly analytic, partly synthetic, it is called
Mixed:"
If LXXXVIII. The Formal Legitimacy of a Probation is-
determined by the following rules,
po^rmai If^ullfy 1% Nothing is to be begged, borrowed, or
of a Probation, - its stolcn ; that is, nothing is to be presupjDosed
as proved, which itself requires a demon-
stration. The violation of this rule afibrds the vice called
the Petitio principii, or Fallacia qucesiti medii (to iv apx^-
aiTCio-^at).^
2°, No proposition is to be employed as a principle of proof,
the truth of which is only to be evinced as a consequence of
the proposition which it is employed to prove. The violation .
of this rule is the vice called varepov -Trporepov.
3", No circular probation is to be made; that is, the propo-
sition which we propose to prove must not be used as a princi-
ple for its own probation. The violation of this rule is called
the Orbis vel circulus in demonstrando, — diallelus, — 6 St?/
aXKriXwv rpoTros.^
1 Ksser, Lo^A, 5 142. — Ed qnod initio fuit propositum et in disquisi^
2 [On error of this term, see Pacius, Cow- tionem vocatum." Ibid, ii, 24. — Ed.]
menlariux in Org ] [In Anal. Prior iL 16. " Non
est petitio t^s o-PX'l^t id est, principii, vel 3 See Sextus Empiricus, Fyrrh. Hyp., i. 169,
iv Tf apxfj, id est, in principio; sed tov iv ii. 68. Laertius, L. ix. H 88, 89. [Cf. Faocio-
^PXV TrpoKeiixfvov, id est, ejus probleraatis, lati, Acroasi.^, v. pi. 69 et seq.]
47
870 LOGIC. Lect. XXVI.
4**, No leap, no hiatus, must be made; that is, the syllogisms
of which the probation is made up must stand in immediate or
continuous connection. From the transgression of this rule
results the vice called the Saltus vel Hiatus in demonstrando.
5°, The scope of the probation is not to be changed ; that is,
nothing is to be proved other than what it was proposed to
prove. The violation of this rule gives the JSeterozetesis, I(/tio-
ratio vel Mutatio elenchi, and the Transitus in aliud genus vel
a genere ad genits, — /xcTaySao-i? dt oAAo ycvos.^
In this paragraph, I have given, as different rules, those canons
which are opposed to vices not absolutely iden-
,Qj^.^ tical, and which have obtained different denom-
inations. But you must observe, that the first
three rules are all manifestly only various modifications — only
special cases, — of one general law. To this law, likewise, the
fourth rule may with perfect propriety be reduced, for the saltus or
hiatus in probanda is, in fact, no less the assumption of a proposi-
tion as a principle of probation which itself requires proof, than
either the petitio principii, the hysteron proteron, or the circulus in
probanda. These five laws, therefore, and the correspondent vices,
may all be reduced to two; ono of which regards the means, — the
principles of proof; the other the end, — the proposition to be
proved. The former of these laws prescribes, — That no proposition
be employed as a principle of probation which stands itself in want
of proof; the lattei*, — That nothing else be proved than the propo-
sition for whose proof the probation was instituted. You may,
therefore, add to the last paragraph the following supplement :
% LXXXIX. These rules of the logicians may, however, all
be reduced to two.
Par. LXXXIX. jo^ That no proposition be employed as
Sules of Probation -r-k'-i f> tt i • i-i i>
reduced to two. ^ Principle of Probation which stands it-
self in need of proof
2**, That nothing else be proved than the Proposition for
whose proof the Probation was instituted.
Of these two, the former comprehends the first
four rules of the logicians, — the latter the fifth.
I shall now, therefore, proceed to illustrate the five rules in detail.
I [See Reinhold, Die Logik oder die altga- 1827] [Cf. Krug, Logik, i 133. Esser, Logik
mtiae Denk/ormenlthre, i 160, p. 407, Jena. { 144. — Ed.]
Lect. XXVI. LOGIC. 371
The First Rule — Nothing is to be begged, borrowed, or stolen ;
that is, notliinir is to be presupposed as proved,
First Rule. . ' » . \ ^ ^ . ' . .
which itself requires a demonstration, — is, in
/act, an enunciation of tha first general rule I gave you, and to this,
therefore, as we shall see, the second, third, and fourth are to be
reduced as special applications. But, in considering this law in its
universality, it is not to be understood as if
Limitation under (3^.^,.^ probation Were at once to be rejected as
which this Rule is to * ' . , . , , . . t i
be understood. woithlcss, in which anything IS presupposed ana
not proved. Were this its sense, it would be
necessary in every probation to ascend to the highest principles
of human knowledge, and these themselves, as immediate and,
consequently, incapable of proof, might be rejected as unproved
assumptions. Were this the meaning of the law, there could be no
probation whatever. But it is not to be understood in this extreme
rigor. That probation alone is a violation of this law, and, conse-
quently, alone is vicious, in which a pi'oposition is- assumed as a
principle of proof, which may be doubted on the ground on which
the thesis itself is doubted, and where, therefore, we prove the un-
certain by the equally uncertain. The probation must, therefore,
depart from such principles as are either immediately given as ulti-
mate, or mediately admit of a proof from other sources than the
proposition itself in question. When, for example, it was argued
that the Newtonian theory is false, which holds colors to be the
result of a diversity of parts in light, on the ground, admitted by
the ancients, that the celestial bodies, and, consequently, their ema-
nations, consist of homogeneous elements; — this reasoning was
inept, for the principle of proof was not admitted by modern phi-
losophers. Thus, when Aristotle defends the institution of slavery
as a natural law, on the ground that the barbai-ians, as of inferior
intellects, are the born bondsmen of the Greeks, and the Greeks, as
of superior intellect, the born masters of the barbarians ' — (an
argument which has, likewise, been employed in modern times in
the British Parliament, with the substitution of negroes for barba-
rians, and whites for Greeks), — this argument is invalid, as assuming
what is not admitted by the opponents of slavery. It would be a
petitio principii to prove to the Mohammedan the divinity of
Christ from texts in the New Testament, "for he does not admit the
authority of the Bible ; but it would be a valid argumentum ad
hominem to prove to him from the Koran the prophetic mission of
Jesus, for the authority of the Koran he acknowledges.
The Second Rule, That no proposition is to be employed aa .a
1 Folit., i. 2. — Ed.
ST2 LOGIC. Lect. XXVL
principle of proof, the truth of which is only to be evinced as a
consequence of the proposition which it is em-
ployed to prove, — is only a special case of the
preceding. For example, if we were to argue that man is a fi-ee
agent, on the ground that he^ is morally responsible for his actions,
or that his actions can be imputed to him, or on the ground that
vice and virtue are absolutely different, — in these cases, the hysteron
proteron is committed ; for only on the ground that the human will
18 free, can man be viewed as a morally responsible agent, and his
actions be imputed to him, or can the discrimination of vice and
virtue, as more than a merely accidental relation, be maintained.
But we must pause before we reject a reasoning on the ground of
hi/stero7i 2yroteron ; for the reasoning may still be valid, though this
logical fault be committed. Nay, it is frequently necessary for us
to reason by sucli a regress. In the very example given, if we be
unable to prove directly that the will of man is free, but are able to
prove that he is a moral agent, responsible for his actions, as sub-
jected to the voluntary but unconditioned Law of Duty, and if the
fact of this law of duty and its unqualified obligation involve, as a
postulate, an emancipation from necessity, — in that case, no com-
petent objection can be taken to this process of reasoning. This,
in fact, is Kant's argument. From what he calls the categorical
imperative, that is, from the fact of the unconditioned law of duty
feS obligatory on man, he postulates, as conditions, the liberty of the
human will, and the existence of a God, as the moral governor of a
moral universe.'
The Thii'd Law, — That no circular probation is to be made, that
is, the proposition which we propose to prove
Third Kale. , - . . , ^ .
must not be used as a prmciple tor its own pro
bation, — this, in like manner, is only a particular case of the fii-st.
"To the Circle there are required properly two probations, which
are so reciprocally related that the antecedent in the one is prove<l
by its own consequent in the other. The proposition A is true be-
cause the proposition B is true; and the proposition B is true
because the proposition A is true. A circle so palpable as this
would indeed be committed by no one. The vice is usually con-
cealed by the interpolation of intermediate propositions, or by a
change in the expression."^ Thus Plato, in his PAopf^o,^ demon-
strates the immortality of the soul from its simplicity ; and, in the
Hepiiblic* he demonstrates its simplicity from its immort.ality.
1 Kriiik det reintn YttnuAfl, Methodenlebre, 2 Krug, Logik, } 183. Anm. 8. —El*.
Hauptst., ii. Abschn., 2. Kritik iler praktischr.n 3 p 78. — Ed.
ftntun/t, p. 274, ed. Rosenkranz. — Ed. * B. x. p. 611. — Ed.
I
hacr. XX VL LOCxic. 378
In relation to the Ilysteron Proteron and the Circfe, I must
observe that these present some peculiar diffi-
Kegressive and Pro- culties for the Systematic arrangement of our
gressive Proofs not to knowledge. Through the Circle (the result of
be confounded with , . , • , , c c ^- \
the tautological Cir. ^hich IS Only the proof of au assertion),—
Ola through the circle by itself, nothing whatever is
gained for the logical development of our knowl-
edge. But we njust take care not to confound the connection of
Regressive and Progressive Proofs with the tautological Circle.
When, in the treatment of a science out of the observed facts, we
wish to generalize universal laws, we lead, in the first place, an in-
ductive probation, that {oti) certain laws there are. Having assured
ourselves of the existence of these laws by this regressive process,
we then place them in theory at the head of a progressive or syn-
thetic probation, in which the facts again recur, reversed and illus-
trated from the laws, which, in the antecedent process, they had
been employed to establish ; that is, it is now shown why (Sion)
these facts exist.
The Fourth Rule, — No leap, no gap, must be made, that is, the
syllogisms of which the probation is made up
Fourth Rule. ,». . ,. .
must stand m mimediate or contmuous connec-
tion,— may be, likewise, reduced to the first. For here the only
vice is that, by an ellipsis of an intermediate link in the syllogistic
chain, we use a proposition which is actually without its proof, and
it is only because this j^roposition is as yet unproved, that its employ-
ment is illegitimate. The Saltus is, therefore, only a special case
of the Petitio.
The Saltus is committed when the middle term of one of the
syllogisms in a probation is not stated. If the
The Saltus in demon- • i j i a. i_ j. t j. j. • j. a.
middle term be too manifest to require state-
timntlo. _ *■
ment, then is the saltus not to be blamed, for it
is committed only in the expression and not in the thought. If the
middle term be not easy of discovery, then the saltus is a fault; but
if there be no middle term to be found, then the saltus is a vice
whieh invalidates the whole remainder of the probation. The
proper saltus^ — the real violation of this law, is, therefore, when
we make a transition from one proposition to another, the two not
being connected together as reason and consequent.^ The (vulgar)
Enthymeme and the Sorites do not, therefore, it ia evident, involve
violations of this law.
The Fifth Rule, — The scope of the probation is not to bo
changed, that is, ftothing is to be proved other than what was pro-
1 Cf. Krug, Logik, S 133. Anm. 4. — Ed.
3T4 LOGIC. Lect. XXVI.
posed to be jjroved, coi*responds to the second of the two niles
which I gave, and of which it is only a less
Fifth Bnie. explicit Statement. It evidently admits of three
A nuts oft ree e- jjjjj^g or degj-ces. In the first case, the proposiT_
tion to be proved is changed by the change of
its subject or predicate into different notions. Again, the propo-
sition may substantially remain the same, but may be changed into
oue either of a wider or of a narrower extension, — the second and
third cases.
The first of these cases is the Mutatio Elenchi, or Transitus ad
alhid genus, properly so called. " When a pro-
irs egree,— «- Nation docs uot demonstrate what it ought to
tatio Elenchi. ^ , °
demonstrate, it may, if considered absolutely or
in itself, be valid ; but if considered relatively to the proposition
which it behooves us to prove, it is of no value. We commute by
this procedure the whole scope or purport of the probation ; we
desert the proper object of inquiry, — the point in question. If a
person would prove the existence of ghosts, and to this end prove
by witness the fact of unusual noises and appearances during the
night, he would prove something very different from what he pro-
posed to establish ; for this would be admitted Mithout difficulty by
those who still denied the apparition of ghosts; it, therefore, be-
hooved him to show that the unusual phenomena were those of a
spirit good or bad."'
The two other cases, — when the proposition actually proved is
either of a smaller or of a greater extension
Second Degree,— in than the proposition which ought to have been
which too little is . ., ... ^,
. proved, — are not. necessarily, like the prece-
ding, altogether irrelevant. They are, however,
compared together, of various degrees of relevancy. In the former
case, where too little is proved, — here the end proposed is, to a
certain extent at least, changed, and the probation results in some-
thing different from what it was intended to accomplish. For
example, if we propose to prove that Sempronius is a virtuous char-
acter, and only prove the legality of his actions, we here prove
something less than, something different from, what we professed to
do ; for we proposed to prove the internal morality, and not merely
the external lawfulness, of his conduct. Such a proof is not abso-
lutely invalid; it is not even relatively null, for the external legality
is always a concomitant of internal morality. But the existence of
the latter is not evinced by that of the former, for Sempronius
I Krug, Loglk, ( 133. Anm. 2. — Ei>.
Lect XXVI. LOGIC. 375
may conform his actions to the law from expediency and not from
duty.*
In the other case, in which there is proved too much, the proba-
tion is lawful, and only not adequate and pre-
rhird Degree,— in ^jgg^ Yov example, if We propose to prove that
which too much is^, ,., .i-iii-i i
^^^gj the soul does not perish with the body, and
actually prove that its dissolution is absolutely
impossible, — here the proof is only superabundant. The logical
rule, — Qui nimium prohat^ nihil prohat, is, therefore, in its univer-
sal, or unqualified expression, incorrect. The proving too much is,
however, often the sign of a saltus having been committed. For
example, — when a religious enthusiast argues from the strength of
his pei-suasion, that he is, therefore, actuated by the Holy Spirit,
and his views of religion consequently true, — there is here too
much proved, for there is implied the antecedent, omitted by a
saltus, that whoever is strongly persuaded of his inspiration is
really inspired, — a proposition too manifestly absurd to bear an
explicit enouncement. In this case, the apparent too much is in
reality a too much which, when closely examined, resolves itself
into a nothing.^
We have thus terminated the consideration of Pure or Abstract
Logic, in both its Parts, and now enter on the Doctrine of Modified
or Concrete Logic.
1 Cf. Krug, Logik, f 133. Anm. 5. — Ed.
S [Cf. Sigwart, Handbuch zu VorUsungtn iiber die Logik, { 407, p. 252.]
LECTURE XXVII.
MODIFIED LOGIC.
PAPT I. -MODIFIED STOICHEIOLOGY.
SECTION I.— DOCTRINE OF TRUTH AND ERROR.
TRUTH. — ITS CHARACTER AND KINDS.
Having now terminated the Doctrine of Pure or Abstract Logic,
we proceed to that of Modified or Concrete
Jiodified Logic, - L .^^ j^ entering on this subject, I have to
its object.
recall to your memory what has formerly been
stated in regard to the object which Modified Logic proposes for
consideration. Pure Logic takes into account only the necessary
conditions of thought, as founded on the nature of the thinking
process itself. Modified Logic, on the contrary, considers the con-
ditions to which thought is subject, arising from the empirical cir-
cumstances, external and internal, under which exclusively it is the
will of our Creator that man should manifest his faculty of think-
ing. Pure Logic is thus exclusively conversant with the form ;
Modified Logic is, likewise, occupied with the matter, of thought.
And as their objects are different, so, likewise, must be their ends.
The end of Pure Logic is formal truth, — the harmony of thought
with thought; the end of Modified Logic is the harmony of thought
with existence. Of these ends, that which Pure Logic proposes is
less ambitious, but it is fully and certainly accomplished ; the end
which Modified Logic proposes is higher, but it is far less perfectly
attained. The problems which Modified Logic has to solve may be
reduced to three: 1**, What is Truth and its con-
* d f^th *"* ~ "* tradictory opposite, — Error? 2°, Whatare the
Causes of Error, and the Impediments to Truth,
by which man is beset in the employment of his faculties, and
what are the Means of their Removal? And, 3°, What are the
f^ibsidiaries by which Human Thought may be strengthened and
guided in the exercise of its functions?
Lect. XXVII. LOGIC. 377
From this statement it is evident that Concrete Logic might, like
Pure Logic, have been divided into a Stoicheiol-
And distributed be- ogy and a Methodologv, — the former conipris-
tvvoeu its Stolcheiol- ■ ^j^^ ^^.^^ ^^^.^ j^^^^^^g^ _ ^^^ j.^^^^,,. ^^j^^ ^jjjj.,|
o;:y and its Methodol- " -.^ t r. i r. • i • i ^ .i
j,^y }* or it to Modmed Stoicheiology we refer the
consideration of the nature of concrete truth
:;nd error, and of the conditions of a merely not erroneous employ-
ment of thought, — this will be exhausted in the First and Second
Chapters ; whereas, if we refer to Methodology a consideration of
the means of employing thought not merely without error, but with
a certain positi\'c perfection, — this is what the Third Chapter pro-
fosses to expound.
I commence the P^'irst Chapter, which proposes to answer the
question, — What is Truth? with its correlatives, ^- by the dict.t-
tion of the following paragraph :
1[ XC. The end which all our scientific efforts are exerted
to accomplish, is Truth and Certainty.
Par. XC. Truth and Tiuth is the Correspondence or agreement
Certainty, — what. _ ' _ p _
of a cognition with its object ; its Crite-
rion is the necessity determined by the laws which govern our
faculties of knowledge ; and Certainty is the consciousness of
this necessity.^ Certainty, or the conscious necessity of knowl-
edge, absolutely excludes the admission of any opposite sup-
position. Where such appeal's admissible, doubt and uncer-
tainty arise. If we consider truth by relation to the degree
and kind of Certainty, we have to distinguish Itnowledge,
Belief., and Opinion. Knowledge and Belief differ not only in
degree, but in kind. Knowledge is a certainty founded upon
insight; Belief is a certainty founded upon feeling. The one
is perspicuous and objective ; the other is obscure and subjec-
tive. Each, however, supposes the other ; and an assurance is
said to be a knowledge or a belief, according as the one element
or the other preponderates. Opinion is the admission of some-
thing as true, where, however, neither insight nor feeling is so
intense as to necessitate a perfect certainty. What prevents
the admission of a proposition as certain is called Doubt, The
approximation of the imperfect certainty of opinion to the poi--
fect certainty of knowledge or belief is called Prohability.
If we consider Truth with reference to Knowledge, and t<»
the way in which . this knowledge arises, we must distinguish
I Cf. Twcsten. Die I.n;;lkJnsbesondereili'; Analytik, { 306. — El>.
4«
B78 LOGIC. Lect. XXVIl
Empirical or a 2^osterioriy from J°ure or a priori 7Vuth. Thfi
former has left-rence to cognitions which have their source in
the presentations of Perception, External and Internal, and
which obtain their form by the ehiboration of the Underetand-
ing or Faculty of Relations (Siavoia). The latter is contained
in the necessary and universal cognitions afforded by the Reg-
ulative Faculty — Intellect Proper — or Common Sense {voW)
This paragraph, after stating that Truth and Certainty constitute
the end of all our endeavors after knowledije.
Explication. /• i • , • ^ , t
tor only m the attainment of truth and certainty
can we possibly attain to knowledge or science; — I say, after the
statement of this manifest proposition, — it proceeds to define what
is meant by the two terms Truth and Certainty; and, to commence
with the former, — Truth is defined, the corresi)ondence or agree-
ment of a cognition or cognitive act of thought with its object.
The question — What is Truth ? is an old and celebrated prob-
lem. It was proposed by the Roman Governor
Truth, — what. . ^^., ~ .
— by Pontius Pilate — to our Saviour; and it
is a question which still recurs, and is still keenly agitated in the
most recent schools of Philosophy. In one respect, all are nearly
agreed in regard to the definition of the term, for
tem^^°'"°° °^ **"* all ^^^^^ that by truth is understood a liarmony,
— an agreement, a correspondence between our
thought and that which we think about. This definition of truth
we owe to the schoolmen. "Veritas intellectus," says Aquinas,
"est adaequatio intellectus et rei, secundum quod intellectus dicit
esse, quod est, vel non esse, quod non est." * From the schoolmen,
this definition has been handed down to modern philosophers, by
whom it is currently employed, without, in general, a suspicion of
its origin. It is not, therefore, in regard to the meaning of the
tei-m truth, that there is any diflference of opinion among philoso-
phers. The questions which have provoked dis-
Questions in e ate cussion, and which remain, as heretofore, without
rej^arding Truth.
a definitive solution, are not whether truth be
the harmony of thought and reality, but whether this harmony, or
truth, be attainable, and wliether we possess any criterion by which
we can be assured of its attainment. Considering, however, at
present only the meaning of the terra, philosophers have divided
Truth (or the harmony of thought and its object) into different
1 [Contra GtntiUs, lib. i. c. 59. See Biunde, general, see Ruiz, Commmt.rfe Seientia^itt Uttt
'UO>r Wahr/ifit in Eikenntn, p. 11. Ou Trutli in t/«- Vrritatf, etc Disp. Ixxxv., p. 871 et stq]
Lect. XXVII. LOGIC. 379
species, to which they have given diverse names ; but they are at
one neither in the division nor in the nomenclature.
It is plain that for man there can only be conceived two kinds of
Truth, because there are for human thought
For man only two ^j^iy ^^^^ spccics of object. For that about
mai and Real ' which WO think must either be a thought, or
something which a thought contains. On this
is founded the distinction of Formal Knowledge and Real Knowl-
edge, — of Formal Truth and Real Truth. Of these in their
order.
I. In regard to the former, a thought abstracted f^jom what it
contains, that is, from its mjftter or what it is
I. Formal Truth. , . , /> o ■, ■,
conversant about, is the mere lorm oi thought.
The knowledge of the form of thought is a formal knowledge, and
the harmony of thought with the form of thought is, consequently,
Foi-mal Truth. * Now Formal Knowledge is of
Formal Truth of ^^.^ kinds ; for it regards either the conditions
lldMa'thematkar" ^^ ^hc Elaborative Faculty, — the Faculty of
Thought Proper, — or the conditions of our
Presentations or Representations of external things, that is, the
intuitions of Space and Time. The former of these sciences is
Pure Logic, — the science which considers the laws to which the
Underetanding is astricted in its elaborative operations, without
inquiring what is the object, — what is the matter, to which these
operations are applied. The latter of these sciences is Mathe-
matics, or the science of Quantity, which considers the relations
of Time and Space, without inquiring whether there be any actual
reality in space or time. Formal truth will, therefore, be of two
kinds, — Logical and Mathematical. Logical truth is the harmony
or agreement of our thoughts with themselves
Logical Truth. , , • , i ,
as thoughts, m other words, the correspondence
of thought with the universal laws of thinking. These laws are
the object of Pure or General Logic, and in these it places the cri-
terion of truth. This criterion is, however, only the negative con-
dition — only the conditio sine qua non, of truth. Logical truth is
supposed in supposing the possibility of thought ; for all thought
presents a combination, the elements of which are repugnant or
congruent, but which cannot be repugnant and congruent at the
same time. Logic might be true, although we possessed no truth
beyond its fundamental laws ; although we knew nothing of any
real existence beyond the formal hypothesis of its possibility.
But were the Laws of Logic purely subjective, that is, were they
true only for our thought alone, and without any objective validity,
810 LOGIC. Lect. XXVII.
oil human sciences (and Mathematics among the rest) would bo
]iurely subjective likewise; for we are cognizant of objects only
under the forms and rules of which Logic is the scieutifio develop-
ment. If the true character of objective validity be universality,
the laws of Logic are really of that character, for these laws con-
strain us, by their own authority, to regard them as the universal
laws not only of human thought, but of universal reason.
The case is the same with the other formal science, the science of
„ ^ . ,^ ^ Quantity, or Mathematics, Without inquiring
Mathematical Truth . . .
into the reality of existences, and without bor-
rowing fron^ or attributing to them anything, Arithmetic, the science
of Discrete QuantRy, creates its numbers, and Geometry, the science
of Continuous Quantity, creates its figures ; and both operate upon
these their objects in absolute independence of all external actuality.
The two mathematical sciences are dependent for their several
objects only on the notion of tJIne and the notion of space, — no-
tions under which alone matter can be conceived as possible, for all
matter supposes space, and all matter is moved in space and in time.
But to the notions of space and time the existence or non-existence
of matter is indifferent; indifferent, consequently, to Geometry and
Arithmetic, so long at least as they remain in the lofty regions of
pure speculation, and do not descend to the practical application of
their principles. If matter had no existence, nay, if space and time
existed only in our minds, mathematics would still be true ; but
their truth would be of a purely formal and ideal character, —
would furnish us with no knowledge of objective realities.*
So much for Formal Truth, under its two species of Logical and
Mathematical.
The other genus of truth — (the end which the Real Sciences
propose) — is the harmony between a thought
II. Ileal Truth. ^ -.^ . mi t^ i o • ,
and Its matter. Ihe Keal feciences are those
Real and Formal ^hich have a determinate reality for their ob-
Sciences. . -, j • ■, i
ject, and which are conversant about existences
other than the forms of thought. The Formal Sciences have a
superior certainty to the real ; for they are simply ideal combina-
tions, and they construct their objects without inquiring about their
objective reality. Tlie real sciences are sciences of fact, for the
point from which they depart is always a fact, —
Under the Real Sci. always a presentation. Some of these rest on
enccs arc included the , . /• r< if • ^v.
Mental and Material ^"^ presentations ot belt-consciousness, or the
facts of mind ; others on the presentations of
{Sensitive Perception, or the facts of nature. The former are the
1 Cf. Esaer. Logik, ♦ 172. — Ep. [Fries, Logik, i 124.^
Lkct. XXVII. LOGIC. S8l
Mental Sciences, the latter the Material. The facts of mind are
given partly as contingent, partly as necessary ; the latter — the
necessary facts — are universal virtually and in themselves ; the
former — the contingent facts — only obtain a fictitious universality
by a process of generalization. The facts of nature, however neces-
sary in themselves, are given to us only as contingent and isolated
phenomena; they have, therefore, only that conditional, that empir-
ical, generality, which we bestow on them by classification.
Real truth is, therefore, the correspondence of our thoughts with
the existences which constitute their objects.
How can wo know But here a difficulty arises ; — How can we know
that there is a corre- ^Jj^t there is, that there can be, such a corre-
spondence between -, n ah.i^ i r- ^-i ^ ' ^ '
,, ,. . ., spondence? All that we know of the obiects is
our thought and its ^ _ *'
Object? through the presentations of our faculties ; but
whether these present the objects as they are in
themselves, we can never ascertain, for to do this it would be requi-
site to go out of ourselves, — out of our faculties, — to obtain a
knowledge of the objects by other faculties, and thus to compare
Our old presentations with our new. But all this, even Were the
supposition possible, would be incompetent to afibrd us the certainty
required. For were it j^ossible to leave our old, and to obtain a
new, set of faculties, by which to test the old, still the veracity of
these new faculties would be equally obnoxious to doubt as the
veracity of the old. For what guarantee could we obtain for the
credibility in the one case, which we do not already possess in the
other? The new faculties could only assert their own truth; but
this is done by the old ; and it is impossible to imagine any presen-
tations of the non-ego by any finite intelligence, to which a doubt
might not be raised, whether these presentations were not merely
subjective modifications of the conscious ego itself. All that could
be said in answer to such a doubt is, that if such were true, our
whole nature is a lie, — a supposition which is not, without the
strongest evidence, to be admitted ; and the argument is as compe-
tent against the skeptic in our present condition, as it would be were
we endowed with any other conceivable form of Acquisitive and
Cognitive Faculties. But I am here trenching on what ought to be
reserved for an explanation of the Criterion of Truth.
Suoh, as it appears to me, is the only rational division of Truth
according to the different character of the ob-
snbdivisiou™ ''•" ' ^ jects to which thought is relative, — into Formal
and itito Real Truth. Formal Truth, as we
have seen, is subdivided into Logical and into Mathgmatical. Real
Truth miglit likewise be subdivided, were this requisite, into vaiious
382 LOGIC. Lect. xxvn.
species. For example, Metaphysical Truth might denote the harmony
of thought with the necessary facts of mind;
Metaphyseal. Psychological Truth, the harmony of thought
^^jj^g^^'j*** ' with the contingent facts of mind ; and Physical
Truth, the harmony of thought with the phae-
nomena of external experience.
It now remains to say a word in regard to the confusion which
has been introduced into this subject, by the
Various applications ^,.^^^^^1^^^ distinctions and contradictions of
of the term Trutk. °
philosophere. Some have absurdly given the
name of truth to the mere reality of existence, altogether abstracted
from any conception or judgment relative to it, in any intelligence
human or divine. In this sense physical truth has been used to
denote the actual existence of a thing. Some have given the name
of metaphysical truth to the congruence of the thing with its idea
in the mind of the Creator. Others again have bestowed the name
of metaphysical truth on the mere logical possibility of being
thought; while they have denominated hy logical truth the meta-
physical or physical correspondence of thought with its objects.
Finally, the term moral or ethical truth has been given to veracity,
or the correspondence of thought with its expression. In this last
case, truth is not, as in the others, employed in relation to thought
and its object, but to thought and its enouncement. So much for
the notion, and the principal distinctions of Truth.
But, returning to the paragraph, I take the next clause, which is,
— "The Criterion of truth is the necessity de-
er tenon o termincd by the laws which govern our faculties
rruth. •' *
of knowledge ; and the consciousness of this
necessity is certainty." That the necessity of a cognition, that is,
the impossibility of thinking it other than as it is presented, — that
this necessity, as founded on the laws of thought, is the criterion of
truth, is shown by the circumstance that where such necessity is
found, all doubt in regard to the correspondence of the cognitive
thought and its object must vanish ; for to doubt whether what we
necessarily think in a certain manner, actually exists as we conceive
it, is nothing less than an endeavor to think the necessary as the
not necessary or the impossible, which is contradictory.
What has just been said also illustrates the truth of the next sen-
tence of the paragraph, — viz., " Certainty or the conscious necessity
of a cognition absolutely excludes the admission of any opposite
supposition. When such is found to be admissible, doubt and un-
certainty arise." This sentence requiring no explanation, I proceed
to the next — viz., " If we consider truth by relation to the degree
Lect. XXVII. logic. 383
and kind of Certainty, we have to distinguish Knowledge, Belief,
and Opinion. Knowledge and Belief differ not only in degree but
in kind. Knowledge is a certainty founded on intuition. Belief is
a certainty founded upon feeling. The one is perspicuous and ob-
jective, the other is obscure and subjective. Each, however, sup-
poses the other, and an assurance is said to be a knowledge or a
belief, according as the one element or the other preponderates."
In reference to this passage, it is necessary to say something in
regard to the difference of Knowledge and Be-
Knowiedge and Be- j-^f. j^ common language the word Belief is
lief, — their difference. , , ? .
often used to denote an inferior degree of cer-
tainty. We may, however, be equally certain
That the certainty •' ^ ^. r.
of all knowledge is ^^ what We bclieve as of what we know, and it
ultimately resolvable has, uot without grouud, been maintained by
into a certainty of Be- many philosophers, both in ancient and in mod-
lief. maintained by ^. 1,^1 • /. 1, 1 1 t •
j^jjjjjgj. em times, that the certainty of all knowledge is,
in its ultimate analysis, resolved into a certainty
of belief "All things," says ^lUther, "stand in a belief, in a faith,
which we can neither see nor comprehend. The man who would
make these visible, manifest, and comprehensible, has vexation and
heart-grief for his reward. May the Lord increase Belief in you
and in others."^ But you may perhaps think that the saying of
Luther is to be taken theologically, and that, philosophically con-
sidered, all belief ought to be founded on knowledge, not all knowl-
edge in belief But the same doctrine is held even by those phi-
losophers who are the least disposed to mysticism or blind faith.
Amonsc these Aristotle stands distinsruished. He
AristoUe. ° . . *
defines science, strictly so called, or the knowl-
edge of indubitable truths, merely by the intensity of our convic-
tion or subjective assurance ;^ and on a primary and incomprehen-
sible belief he hangs the whole chain of our comprehensible or
mediate knowledge. The doctrine which has been called The Phi-
losophy of Common Sense, is the doctrine which founds all our
knowledge on belief; and, though this has not been signalized, the
doctrine of Common Sense is perhaps better stated by the Stagirite
than by any succeeding thinker. "What," he says, "appears to all
men, that we affirm to be, and he who rejects this belief (Trtcrris) will
assuredly advance nothing better worthy of credit." This passage
is from his Nicomachean Ethics? But, in his Physical Treatises, he
founds in belief the knowledge we have of the reality of motion,
1 Weiahth, Th. iii. Abth., 2. Quoted by Sir effect are cited by the Author, RtiO's TTorii,
W. Hamilton, K^/rf's Works, pi 778. — Ed. p. 771. — Ed.
2 Various passages from Aristotle to this 3 B. x. c. 2. — Ed.
.384 LOGIC. Lect. XXVIL
<
and by this, as a source of knowledge paramount to the Understand-
ing, he supersedes the contradictions which are involved in our con-
ception of motion, and which had so acutely been evolved by the
Eleatic Zeno, in order to show that motion was impossible.^ In
like manner, in his Logical Treatises, Aristotle shows that the
primr.ry or ultimate principles of knowledge must be incomprehen-
sible ; for if comprehensible, they must be comprehended in some
higher notion, and this again, if not itself incomprehensible, must
be again comprehended in a still higher, and so on in a progress ad
infinititm, which is absurd.'' But what is given as an ultimate and
incomprehensible principle of knowledge, is given as a fact, the
existence of which wo must admit, but the reasons of whose exist-
ence we cannot know, — we cannot understand. But such an ad-
mission, as it is not a knowledge, must be a belief; and thus it is
that, according to Aristotle, all our knowledge is in its root a blind,
a passive faith, in other words, a feeling. The same doctrine was
subsequently held by many of the acutest think-
ers oi ancient tigies, more especially among the
Platonists ; and of these Proclus is perhaps the
j)hilosoi)her in whose works the doctrine is turned to the best
account.^ In modem times we may trace it in silent operation,
though not explicitly proclaimed, or placed as the foundation of a
system. It is found spontaneously i*ecognized even by those who
might be supposed the least likelv to acknowl-
Hume. * . . / ^ , . -^-. -
edge It without compulsion. Hume, tor exam-
ple, against whose philosophy the doctrine of Common Sense was
systematically arrayed, himself pointed out the weapons by which
his adversnries subsequently assailed his skepticism; for he himself
was possessed of too much philosophical aciiteness not to perceive
that the root of knowledge is belief. Thus, in his Inquiry^ he says
■*— " It seems evident that men are carried by a natural instinct or
prepossession to repose foith in their senses: and that, without any
reasoning, or even almost before the use of reason, we always sup-
pose an external universe which depends not on our preception, but
would exist though we and every sensible creature were absent or
annihilated. Even the animal creation are governed by a like
ojjinion, and preserve this belief, — the belief of external objects, in
all their thoughts, designs, and actions This very table,
which we see white, and whioh we feel hard, is believed to exist
1 U. viii. c. 3. SeeiJeirf'4 Worts, p. 773.— Ed. ^ In. Platonis Vuologiam, i.e. 25. Quoted
, S Mftaphys., iii. (iv.) 4. Cf. Anal. P»st., i. 3, in HtiW* (Tarvb, p. 77C. — Ed.
3. — Ed
lect. xxvil logic. 385
independent of our perception, and to be something external to our
mind which perceives it." ^
But, on the other hand, the manifestation of this belief necessa-
rily involves knowledge ; for we cannot believe
The manifestation without somc cousciousness or knowledge of
of Belief involves ^i i t r> -, ,i -^i ^
^jg^ g the beher, and, consequently, without some con-
sciousness or knowledge of the object of the
belief. Now, the immediate consciousness of an object is called an
intxiUion, — an insight. It is thus impossible to
separate belief and knowledge, — feeling and
intuition. They each suppose the other.
The consideration, however, of the relation of Belief and
Knowledge does not properly belong to Logic,.
Tiie question as to except in SO far as it is necessary to explain i
, „ , , the nature of Truth and Error. It is alto-
and Knowledge prop-
erly metaphysical, gether a metaphysical discussion; and one of
the most difficult problems of which Meta-
physics attempts the solution.
The remainder of the paragraph contains the statement of cer-
tain distinctions and the definition of certain terms, which it was-
necessary to signalize, but which do not requii'e any commentary
for their illustration. The only part that might have required an-
explanation is the distinction of Truth into Pure, or a priori, and
into Empirical, or a posteriori. The explanation of this division ;
has been already given more than once in the course of the Lec-
tures,^ but the following may now be added.
Experience presents to us only individual objects, and as these
individual objects might or might not have
ure an mpinc come within our sphere of observation, our
Truth. '
whole knowledge of and from these objects
might or might not exist; — it is merely accidental or contingent.
But as our knowledge of individual objects affords the possibility,,
as supplying the whole contents, of our generalized or abstracted
notions, our generalized or absttacted notions are, consequently, not
more necessary to thought, than the particular observations out of
which they are constructed. For example, every horse I have seen;;
I might not have seen ; and I feel no more necessity to think the-
reality of a horse than the reality of a hippogriff; I can, therefore,
easily annihilate in thought the existence of the whole species. I
can suppose it not to be, — not to have been. The case is the same
1 Inquiry concfrning the Human Undtntand- 2 See above, Lectures on Metnphijsics, p. 403-
>ng. sect. 12. PhilosophiccU Works, iv. p. 177. et seq. Cf. Esser, Logik, H 4, 171. — Ed.
— Ed. [Fries, Logik, } 124.]
.49
8S6 LOGIC. Lect. xxvii.
with every other notion which is mediately or immediately the
datum of observation. We can think away each and every part
of the knowledge we have derived fi-om experience ; our whole
empirical knowledge is, therefore, a merely accidental possession
of the mind.
But there are notions in the mind of a very different character, —
notions which we cannot but think, if we think at all. These,
therefore, are notions necessary to the mind; and, as necessary,
they cannot be the product of experience. For example, I perceive
something to begin to be. I feel no necessity to think that this
thing must be at all, but thinking it existent, I cannot but think
that it has a cause. The notion, or rather the judgment, of Cause
and Effect, is, therefore, necessary to the mind. If so, it cannot be
derived from experience.
LECTURE XXVIII.
MODIFIED STOIOHEIOLOQY.
SECTION I. — DOCTRINE OF TRUTH AND ERROR.
«
SECTION II. — ERROR, — ITS CAUSES AND REMEDIES.
A. — GENERAL CIRCUMSTANCES — SOCIETY.
I NOW proceed to the consideration of the opposite of Truth, —^
Erroi", and, on this subject, give you the following paragraph :
% XCI. Error is opposed to Truth ; and Error arises, I*,
From the commutation of what is Subjec*
Par. xcr. Error,- tivc with what is Objcctive in thought;
2°, From the Contradiction of a supposed
sources.
knowledge with its Laws ; or, 3", From a
want of Adequate Activity in our Cognitive Faculties.
Error is to be discriminated from Ignorance and from lUu-
sion ; these, however, along with Arbitrary Assumption, afford
the most frequent occasions of error.'
This paragraph consists of two parts, and these I shall succes-
sively consider. The first is : ' Error is opposed
fixpiication. , , _ . , „ -n ,
to truth; and Error arises, 1°, trom the com-
mutation of what is subjective with what is objective in thought;
2°, From the contradiction of a supposed knowledge with its laws;
or, 3°, From a want of adequate activity in our cognitive faculties.'
" In the first place, we have seen that Truth is the agreement of
a thought with its obiect. Now, as Error is the
Error,- what. • ^ , t,
opposite oi truth, — Error must necessarily con-
sist in a want of this agreement. In the second place, it has been
J Twesten, Die Logik,insbesondere die Analytik, §§ 308, 309. — Ed. [Cf. Ruiz, Commentarius «*»■
Scienlia, etc. Disp. xcii. p. 925.]
888 LOGIC. Lkct. XXVUl
shown that the criterion or standard of truth is the necessity
founded on the laws of our cognitive faculties; and from this it
follows that the essential character of error must be, either that it
is not founded on these laws, or that it is repugnant to them. But
these two alternatives may be viewed as only one ; for inasmuch as,
in the former case, the judgment remains undecided, and can make
no pretence to certainty, it may be thrown out of account no less
than in the latter, where, as positively contradictory of the laws of
knowledge, it is necessarily false. Of these statements the firet,
that is, the non-agreement of a notion with its
As Material. ... . , .
object, IS error viewed on its material side ; and
as a notion is the common product, — the joint result aflTorded by
the reciprocal action of object and subject, it is evident that what-
ever the notion contains not correspondent to the object, must be a
contribution by the thinking subject alone, and we are thus war^
ranted in saying that Material Error consists in the commuting of
what is subjective with what is objective in thought ; in other
words, in mistaking an ideal illusion for a real representation. The
second of these statements, that is, the incon-
As Formal. o ^ -, ...
gruence of the supposed cognition with the
Jaws of knowledge, is error viewed on its formal side. Now here
the question at once presents itself, — How can an act of cognition
contradict its own laws ? The answer is that it cannot ; and error,
when more closely scrutinized, is found not so
Arises from the much to consist in the contradictory activity of
want of adequate ac- ... n i^- • .i_ • . r ^•
r .X. r> • our cognitive faculties as in their want oi act:v-
tivlty of the Cogni- » ^
tire Faculties. ity. And this may be in consequence of one or
other of two causes. For it may arise from
some other mental power, — the will, for example, supei^seding, —
taking the place of, the defective cognition, or, by its intenser force,
turning it aside and leading it to a false result ; or it may arise from
borne want of relative perfection in the object, so that the cognitive
faculty is not determined by it to the requisite degree of action.
"What is actually thought, cannot but be correctly thought-
Error first commences when thinking is remitted, and can in fact
only gain admission in virtue of th6 truth which it contains; —
dvery error is a perverted truth. Hence Descartes* is justified in
the establishment of the principle, — that we would never admit
the false for the true, if we would only give assent to what we
clearly and distinctly apprehend. 'Nihil nos unquam falsum pro
vero admissuros, si tantum iis assensum praebeamus, quaj clare et
1 Principia Philosophia, i. 4a Cf. Med. Ir. De Vero et Fatso.
Lect. XXVUI. LOGIC. 38Ji
distincte perciijimus.' " ^ In this view the saying of the Roman'
poet —
"Nam neqae decipitur ratio, nee decipit unqnam,"2
-7- is no longer a paradox; for the condition of error is not the
activity of intelligence, but its inactivity.
So much for the first part of the paragraph. The second is — .
' Error is to be discriminated from Ignorance and
Error discriminated f^.^^ Illusion, which, howcver, along with Avbi-
jjj^gj^j, trary Assumption, afford the usual occasions of.
Error.'
. "Ignorance is a mere negation, — a mere not-knowledge ; whereas .
in error there lies a positive pretence to knowl-
Ignorance. ....
edge. Hence a representation, be it imperfectv,
be it even without any correspondent objective reality, is not in
itself an error. The imagination of a hippogriflf is not in itself .
false ; the Orlando Fnrioso is not a tissue of errors. Error only ;
arises when we attribute to the creations of our minds some real •
object, by an assertory judgment; we do not err and deceive either
ourselves or others, when we hold and enounce a subjective or ,
problematic supposition only for what it is. Ignorance, — not'
knowledge, — however, leads to error, when we either regard the •
unknown as non-existent, or when we falsely fill it up. The latter
is, however, as much the result of Will, of arbitrary assumption, as
of ignorance ; and, frequently, it is the result of both together. In
general, the will has no inconsiderable share in the activity by
which knowledge is realized. The will has not immediately an
influence on our judgment, but mediately it has. Attention is an
act of volition, and attention furnishes to the Understanding the
elements of its decision. The will determines whether we shall
carry on our investigations, or break them off, content with the first
apparent probability ; and whether we shall apply our observations
to all, or, only partially, to certain, momenta of determination.
" The occasions of Error which lie in those qualities of Present;:-
tion. Representation, and Thought arising from
Illusion. ' \. . '. - r. 1 1 ■ ^ '
the conditions and influences of the thinking
subject itself, are called Illusions. But the existence of illusion
does not necessarily imply the existence of error. Illusion becomes
error only when we attribute to it objective truth ; whereas illusion
i-: no error when we regard the fallacious appearance as a mere sub-
jiH'tive affection. In the jaundice, we see everything tinged with
yullow, in consequence of the suffusion of the eye with bile. lu
1 Twesten, Logik, } 308. -' Ed. 2 Manilius, ii. 131. —Ed.
390 LOGIC. Lkct. xxvm.
this case, the yellow vision is illusiou ; and it would become error,
were we to suppose that the objects we perceive were really so col-
ored. All the powei-s which cooperate to tlie formation of our
judgments, may become the sources of illusion,
lis sources. i i i • c- mi
and, consequently, the occasions of error. 1 he
Senses,^ the Presentative Faculties, External and Internal, tho
Representative, the Retentive, the Reproductive, and the Elab-
orative, Faculties, are immediate, the Feelings and the Desires
are mediate, sources of illusion. To these must be added the
Faculty of Signs, in all its actual manifestations in language.
Hence we speak of sensible, psychological, moral, and symbolical,
illusion."^ In all these relations the causes of illusion are partly
general, partly particular; and though they proximately manifest
themselves in some one or other of these forms, they may ulti-
mately be found contained in the circumstances by which tho
mental character of the individual is conformed. Taking, there-
fore, a general view of all the possible Sources of Error, I think
they may be reduced to the following classes, which, as they consti-
tute the heads and determine the order of the ensuing discussion, I
shall comprise in the following paragraph, with which commences
the consideration of the Second Chapter of Mt>dified Logic. Be-
fore, however, proceeding to consider these several classes in their
order, I may observe that Bacon is the first phi-
Bacon a ciassifica- losopher who attempted a systeniatio enumera-
tion of tUe gources of . „ ,, . ^ « i , •
„ „_ lion or the various sources oi error;' and hia
error. '
quaint classification of these, nnder the signifi-
cant name of idols, into the four genera of Idols of the Tribe {idola
tribiis). Idols of the De?) {idola specus). Idols of the Forum {idola
fori), which may mean either the market-place, the bar, or the
place of public assembly, and Idols of the Theatre {idola theatri),
he thus briefly characterizes.
\ XCII. The Causes and Occasions of Eiror are compre-
hended in one or other of the four foUow-
ar. rror,- -^ classcs. For thcv are found either, l".
In the General Circumstances which mod-
ify the intellectual character of the individual ; or, 2°, In the
I La Fontaine. See Maznre, Court de Phi- g^rent. C'est ce que La Fontaine a tiia bien
losopMe, ii. 241. [Toutcs )es sciences natnr- exprim^ dans les vers suiraat:
dies ne sont autre cliose qn'une j{uerre ou-
verte dc la raison contre lis deceptions de Is " **""""* '' '"" '^"""'^ °° **^°' "• "'*•'' " ~
^ ,..,.., , i ,- , ,1 . drcM*," etc. — Ed.
M!n8ibiIit<S e'est-a-dire, qu'elles ont
pour objet de rifornerles erreurs de noa sens, S [Twesten, Logik, f 309, pp. 288. 289. Ci
et dc substituer les rialites de la .science aux Sigwart, Logik, ^ 484, 485.]
apparences factices que uos i>eu8 nous sug- 3 Novum Orgaautn, l Aph. xxxix. — Eo>
Leer. XXVin. LOGIC. 391
Constitution, Habits, and Reciprocal Relations of his powers
of Cognition, Feeling, and Desii^e ; or, 3°, In the Language
which he employs, as an Instrument of Thought and a Medium
of Communication ; or, 4°, In the nature of the Objects them-
selves, about which his knowledge is conversant.
•
% XCIII. Under the General Circumstances which modify
the character of the individual, are compre-
-,,t'* „«^„.,^.t»«rr. bended, 1°. The particular degree of Culti-
eral circumstances ' i o
which modify the vatiou to which his natiou has attained ;
vduai ^'^° ^^^ ^ ^*^'' ^^^ I'udeness, the partiality of its civili-
zation, and its over-refinement are all mani-
fold occasions of error ; and this cultivation is expressed not
merely in the state of the arts and sciences, but in the degree
of its religious, political, and social advancement; 2°. The
Stricter Associations, in so far as these tend to limit the free-
dom of thought, and to give it a one-sided direction ; such
are Schools, Sects, Orders, Exclusive Societies, Corporations,
Castes, etc.^
In the commen<;nment of the Course, I had occasion to allude to
the tendency there is in man to assimilate in
Explication. Man opinions and habits of thoucrht to those with
by nature isocial, and i i , <>■««■• i "^
influenced by the vvhom he lives. Man IS by nature, not merely
opinions of his fellows. by accidental necessity, a social being. For
only in society does he find the conditions
which his diflferent ficulties require for their due development and
application. But society, in all its forms and degrees, from a fam-
ily to a State, is only possible under the condition of a certain har-
mony of sentiment among its members; and as man is by nature
destined to a social existence, he is by nature determined to that
analogy of thought and feeling which society supposes, and out of
which society springs. There is thus in every association, great
and small, a certain gravitation of opinions towards a common
centre. As in our natural body every part has a necessary sympathy
with every other, and all together form, by their harmonious con-
spiration, a healthy whole ; so, in the social body, there is always a
strong predisposition in each of its members to act and think in
unison with the rest. This universal sympathy or fellow-feeling is
the principle of the different spirit dominant in different ages,
countries, ranks, sexes, and periods of life. It is the cause why
fashions, why political and religious enthusiasm, why moral example
1 Bachniann, Logik, \\ 402, 403. — Ed. 2 See Lectures on Mitap/iysics, p. 59. —Ed.
392 LOGIC. Lect. xxvm.
either for good or evil, spread so rapidly and exert so powerful an
influence. As men are natur.'tlly prone to imitate others, they, con-
sequently, regai'd as important or insignificant, as honorable or dis-
graceful, as true or false, as good or bad, what those around them
consider in the same light.*
Of the various testimonies ? formerly quoted, of the strong as-
similating influence of man on man, and of the
PaFcal quoted on the r i. j. iii,^ * x
, power of custom to make that apT)ear true, nat-
power of custom. ^ ...
ural, and necessary, which in reality is false, un-
natural, and only accidentally suitable, I shall only adduce that of
Pascal. "In the just and the unjust," says he, " we find hardly any-
thing which does not change its character in changing its climate.
Three degrees of an elevation of the pole reverses the whole of
jurisprudence. A meridian is decisive of truth, and a few years, of
possession. Fundamental laws change. Right has its epochs. A
pleasant justice which a river or a mountain limits ! Truth on this
side the Pyrenees, error on the other !"* It is the remark of an in-
genious philosopher, " that if we take a survey of the universe, all
nations will be found admiring only the reflection of their own
qualities, and contemning in others whatever is contrary to what
they are accustomed to meet with among themselves. Here is the
Englishman accusing the French of frivolity; and here the French-
man reproaching the Englishman with selfishness and brutality.
Here is the Arab persuaded of the infallibility of his Caliph, and
deriding the Tartar who believes in the immortality of the Grand
Lama. In every nation we find the same congratulation of their
own wisdom, and the same contempt of that of their neighbors.
" Were there a sage sent down to earth from heaven, who regu-
lated his conduct by the dictates of pure reason alone, this sage
would be universally regarded as a fool. He would be, as Socrates
says, like a physician accused by the pastry-cooks, before a tribunal
of children, of prohibiting the eating of tarts and cheese-cakes ; a
crime undoubtedly of the highest magnitude in the eyes of his
judges. In vain would this sage support his opinions by the clear-
est arguments, — the most irrefragable demonstrations ; the whole
world would be for him like the nation of hunchbacks, among
whom, as the Indian fabulists relate, there once upon a time ap-
peared a god, young, beautiful, and of consummate symmetry. This
god, they add, entered the capital; he was there forthwith sur-
rounded by a crowd of natives; his figure appeared to them extra-
I [Melners, Untersuchungen Mer die Drnlc- 2 P^twrfes, partie i. art. vi. 4 8 (vol. il. p 126,ed
icidfte undf. WiUtnskrifle dti Menschen, ii. 322.] Faugere). Comp. Leet. on Metaphysics, p. 00
Lect. XXVm. LOGIC. 393
ordinary ; laughter, hooting, and taunts manifested their astonish-
ment, and they were about to carry their outrages still further, had
not one of the inhabitants (who had undoubtedly seen other men),
in order to snatch him from the danger, suddeijly cried out — 'My
friends ! my friends ! What are we going to do ? Let us not insult
this miserable monstrosity. If heaven has bestowed on us the gene-
ral gift of beauty, — if it has adorned our backs with a mount of
flesh, let us with pious gi'atitude repair to the temple and render
our acknowledgment to the immortal gods.' " This fable is the his-
tory of human vanity. Every nation admires its own defects, and
contemns the opposite qualities in its neighbors. To succeed in a
country, one must be a bearer of the national hump of the people
among whom he sojourns.
There are few philosophers who undertake to make their country-
men aware of the ridiculous figure they cut In
The art of doubting ^]jg gyg ^f reason ; and still fewer the nations
well diflScult to teach , ^ -i . r>. i .1 i • a ^^
and 10 learn ^^ ^^® *° pront by the advicc. All are so
punctiliously attached to the interests of their
vanity, that none obtain in any country the name of wise, except
those who are fools of the common folly. There is no opinion too
absurd not to find nations ready to believe it, and individuals
prompt to be its executioners or its martyrs. Hence it is that the
philosopher declared, that if he held all truths shut up within his
hand, he would take especial care fiot to show them to his fellow-
men. In fact,- if the discovery of a single truth dragged Galileo to
the prison, to what punishment would he not be doomed who should
discover all ? Among those who now ridicule the folly of the human
intellect, and are indignant at the persecution of Galileo, there are
few who would not, in the age of that philosopher, have clamored
for his death. They would then have been imbued with difierent
opinions ; and opinions not more passively adopted than those
which they at present vaunt as liberal and enlightened. To learn
to doubt of our opinions, it is sufficient to examine the powers of
the human intellect, to survey the circumstances by which it is af-
fected, and to study the history of human follies. Yet in modem
Europe six centuries elapsed from the foundation of Universities
until the appearance of that extraordinary man, — I mean Des-
cartes, — whom his age first persecuted, and then almost worship-
ped as a demi-god, for initiating men in the art of doubting, — of
doubting well, — a lesson at which, however, both their skepticism
and credulity show that, after two centuries, they are still but awk-
ward scholars. Socrates was wont to say — " All that I know is
50
S94 LOGIC. Lect. XX VUI
that I know nothing."^ In our age it would seem that men know
everything except what Socrates knew. Our errors would not be
80 frequent were we less ignorant ; and our ignorance more curable,
did we not believe ourselves to be all-wise.
Thus it is that the influence of Society, both in its general form
of a State or Nation, and jn its particular forms of Schools, Sects,
etc., determines a multitude of opinions in its menibei*s, which, as
they are passively received, so they are often altogether erroneous.
Among the more general and influential of these there are two,
which, though apparently contrary, are, how-
oftiie influence of ex- ever, both, in reality, founded on the same in-
ample, capacity of independent thouglit, — on the same
1. Prejudice in fa- influence of example, — I mean the excessive
admiration of the Old, and the excessive admi-
ration of the New. The former of these prejudices,^ — under which
may be reduced the prejudice in favor of Authority, — was at one
time prevalent to an extent of which it is difficult for us to form a
conception. This prejudice is prepared by the very education not
only which we do, but which Ave all must re-
pare y uca- ceive. The child necessarily learns everything
at first on credit, — he believes upon authority.
But when the rule of authority is once established, the habit of pas-
sive acquiescence and belief is formed, and, once formed, it is not
again always easily thrown off. .When the child has grown up to
an age in which he might employ his own reason, he has acquired a
large stock of ideas ; but who can calculate the number of errora
which this stock contains ? and by what means is he able to dis-
criminate the true from the false ? His mind has been formed to
obedience and uninquiry ; he possesses no criterion by which to
judge ; it is painful to suspect what has been long venerated, and it
is felt even as a kind of personal mutilation to tear up what has be-
come irradicated in his intellectual and moral being. Poiiere diffi-
cile est quoB placuere diu. The adult doea not, therefore, often judge
for himself more than the child ; and the tyranny of authority and
foregone opinion contiimes to exert a sway during the whole course
of his life. In our infancy and childhood the credit accorded to our
parents and instructors is implicit; and if what wo have learned
from them be confirmed by what we hear from others, the opinions
1 riafo, Apol , p 23. — Ed. ft dm Prejuges repandus dans la Socidc, Paris,
2 [On Prejudice in pencral see the IbllowmR 1810—1813, 3 vols. 8va J. L. Cnstillon, Essai
works: — Diiinarsais, E^sai sur Us Prcjuges, siir U.t Errrurs et Us superstitions Ancieunes M
new ed., Pnri.«, 1822. Examen ilt V Esun sur Moiitmrs, Amsterdam, 1705; l^aris, 1767. Sir
/',« ^([/'/i'J.t, l?oiJ. 1777. K^tni sur let Prejii!i<is, Thomas Brown, Vulgar Errors, lilauvil, £t-
Neucbttel, 179G. J. 11. .Suliiuvs, U-s Err>urs suys.\
Lect. XXVIII. LOGIC. 395
thus recommended become at length stamped in almost indelible
characters uj^on the mind. This is the cause why men so i-arely
abandon the opinions which vulgarly pass current ; and why what
comes as new is by so many, for its very novelty, rejected as false.
And hence it is, as already noticed, that truth is as it were geo-
graphically and politically distributed ; what is truth on one side
of a boundary being error and absui'dity on the other. What has
now been said of the influence of society at large, is true also of the
lesser societies which it contains, all of which impose with a stronger
or feebler, a wider or more contracted, authority, certain received
opinions upon the faith of the members. Hence it is that whatever
has once obtained a recognition in any society, large or small, is not
rejected when the reasons on which it was originally admitted
have been proved erroneous. It continues, even for the reason that
it is old and has been accepted, to be accepted still ; and the title
wliich was originally defective, becomes valid by continuance and
prescription.
But opposed to this cause of error, from the prejudice in favor of
the Old, there is the other, directly the reverse,
reju ice in avor — ^j^^ prejudice in favor of the New. This
of the>ew. .
prejudice may be, in part at least, the result of
sympathy and fellow-feeling. This is the cause why new opinions,
however erroneous, if they once obtain a certain number of con-
verts, often spread with a rapidity and to an extent, which, after
their futility has been ultimately shown, can only be explained on
the ])rinciple of a kind of intellectual contagion. But the^ principal
cause of the prejudice in favor of novelty lies in the Passions, and
the consideration of these does not belong to the class of causes
with which we are at present occupied.
Connected with and composed of both these prejudices, — that in
favor of the old and that in favor of the new, —
AuZrur^*^'"'"'** *^®'"^ ^^ ^^® prejudice of Learned Authority;
for this is usually associated with the prejudices
of Schools and Sects. "As often as men have appeared, who, by the
force of their genius, have opened up new views of science, and thus
contributed to the progress of human intellect, so often have they,
likewise, afforded the occasion of checking its advancement, and of
turning it from the sti'aight path of improvement. Not that this
result is to be imputed as a reproach to them, but simply because it
is of the nature of man to be so affected. The views which influ-
enced these men of genius, and which, consequently, lie at the
foundation of their works, are rarely comprehended in their totality
by those who have the names of these authors most frequently in
896 LOGIC. Lect. XXVIIL
their mouths. The many do not concern themselves to seize the
ideal which a philosopher contemplated, and of which his actual
works are only the imperfect representations ; they appropriate
to themselves only some of his detached apothegms and proposi-
tions, and of these compound, as they best can, a sort of system
suited to their understanding, and Avhich they employ as a talisman
in their controversies with others. As their reason is thus a captive
to authority, and, therefore, unable to exert its native freedom, they,
consequently, catch up the true and the false without discrimina-
tion, and remain always at the point of progress where they had
been placed by their leaders. In their hands a system of living
truths becomes a mere petrified organism ; and they require that the
whole science shall become as dead and as cold as their own idol.
Such was Plato's doctrine in the hands of the Phitonists ; such was
Aristotle's philosophy in the hands of the Schoolmen ; and the his-
toiy of modern systems affords equally the same result."*
So much for the first genus into which the Sources of Error are
divided.
I BacbinaoD, Logii, S 404, p. 560- — Ed.
LECTURE XXIX.
MODIFIED S T O I C H E I O L O O Y.
SECTION II. — ERROR — ITS CAUSES AND REMEDIES
A. — GENERAL CIRCUMSTANCES — SOCIETY.
B. — AS IN POWERS OF COGNITION, FEELING, AND DESIRE.
L — AFFECTIONS. — PRECIPITANCY— SLOTH — HOPE AND FEAR-
SELF-LOVE.
In our last Lecture, we entered on the consideration of the
various sources of Error. These, I stated, may
Recapitulation. . i t i ,. i t t
be conveniently reduced to tour heads, and con-
sist, 1°. In the General Circumstances which modify tlie intellectual
character of the individual ; 2°. In the Constitution, Habits, and
Reciprocal Relations of his powers of Cognition, Feeling, and
Desire ; 3°. In the Language which he employs as an Instrument
of Thought and a Medium of Communication ; and, 4°. In the
nature of the Objects themselves about which his knowledge is
conversant.
Of these, I then gave you a general view of the nature of those
occasions of Error, which originate in the circumstances under the
influence of which the character and opinions of man are deter-
mined for him as a member of society. Under this head I stated,
that, as man is destined by his Creator to fulfil the end of hia
existence in society, he is wisely furnished with a disposition to
imitate those among whom his lot is cast, and thus conform himself
to whatever section of human society he may by birth belong, or
of which he may afterwards become a member. The education we
receive, nay the very possibility of receiving education at all, sup-
poses to a certain extent the passive infusion of foreign and tradi-
tionary opinions. For as man is compelled to think much earlier
than he is able to think for himself, — all education necessarily
imposes on him many opinions whicli, whether in themselves true
398 LOGIC. Lect. XXIX.
or false, are, in reference to the recipient, only prejudices; and it is
even only a small number of mankind who at a later period are
able to bring these obtruded opinions to the test of reason, and by
a free exercise of their own intelligence to reject them if found
false, or to acknowledge them if proved true.
But while the mass of mankind thus remain, during their whole
lives, only the creatures of the accidental circumstances which have
concuiTcd to form for them their habits and beliefs;* the few who
are at last able to form opinions for themselves, are still dependent,
in a great measure, on the unreasoning judgment of the many.
Public opinion, hereditary custom, despotically impose on us the
capricious laws of propriety and manners. The individual may
possibly, in matters of science, emancipate himself from their servi-
tude ; in the affaii-s of life he must quietly submit himself to the
yoke. The only freedom he can here prudently manifest, is to
resign himself Avith a consciousness that he is a slave not to reason
but to conventional accident. And while he conforms himself to
the usages of his own society, he will be tolerant to those of others.
In this respect his maxim will be that of the Scythian prince :
"With you such may be the custom, — with us it is different."
So much for the general nature of the infln-
Means by which ihe ence to wliicli we are exposed from the circum-
Infliience of society, as , f c< • ^ '^ • ^ i.^
- ■ stances of bociety : it now remams to sa3' what
a source of error, . . .
may be counteracted. f"*e the means by which this influence, as a
source of error, may be counteracted.
It has been seen that, in consequence of the manner in which
our opinions are formed for us by the accidents
Necessary to insti- of society, our imposed and supposed knowledge
tute a critical examin- . j?i 31 o ^ ^\ 3 tt
, ^ , . IS a contused medley or truths and erroi-s. Here
atlon of the contcuts ^ ^ •'
of our knowledge. it is evidently necessary to institute a critical
examination of the contents of this knowledge.
Descartes proposes that, in order to discriminate, among our preju-
diced opinions, the truths from the errors, we ought to commence
by doubting all.* This has exposed him to much obloquy and
clamor, but most unjustly. Tlie doctrine of Descartes has nothing
skeptical or offensive ; for he only maintains
Descartes, -his pre- ^^^^ j^ behooves US to examine all that has
been inculcated on us from infancy, and under
the masters to whose authority we have been subjected, with the
same attention and circumspection which we accord to dubious
questions. In fact there is nothing in the precept of Descartes,
which bad not been previously enjoined by other philosophers.
1 Discours de la Mitkodt, Partie ii. — Ed.
Lect. XXIX. LOGIC. 399
Of these I formerly quoted to you several, and among others tho
remarkable testimonies of Aristotle, St.Augustin, and Lord Bacon.^
But although there be nothing reprehensible in the precept of
Descartes, as enounced by him, it is of less prac-
Conditions winch iiQal Utility in cousequencc of no account being
taken of the circumstances which condition and
tion.
modify its application. For, in the first place,
the judgments to be examined ought not to be taken at random,
but selected on a principle, and arranged in due order and depend-
ence. But this requires no ordinary ability, and the distribution of
things into their proper classes is one of the last and most difficult
fruits of philosophy. In the second place, there are among our
prejudices, or pretended cognitions, a great many hasty conclusions,
the investigation of which requires much profound thought, skill,
and acquired knowledge. Kow, from both of these considerations,
it is evident that to commence philosophy by such a review, it is
necessary for a man to be a philosopher before he can attempt to
become one. The precept of Descartes is, therefore, either unrea-
sonable, or it is too unconditionally expressed. And this latter
alternative is true.
What can be rationally requii'ed of the student of philosophy, is
not a preliminary and absolute, but a gradual
A j^radual and pro- ^ . •' , « . ,. t^
gressive abrogation of '^^^^ progressive abrogation, of prejudices. It
prejudices all that can can onlv be required of him, that, when, in the
be required of the stu- course of his Study of philosophy, he meets with
dent of philoeophy. .,. i-ii ,i i i a?
a proposition which has not been already sutn-
ci en tly sifted, — (whether it has been elaborated as a principle or
admitted as a conclusion), — he should pause, discuss it without
prepossession, and lay aside for future consideration all that has not
been subjected to a searching scrutiny. The precept of Descartes,
when rightly explained, corresponds to that of St. Paul -J "If any
man among you seemeth to be wise in this world, let him become a
fool, that he may be wise ; " that is, let him not rely more on the
opinions in which he has been brought up, and in favor of which he
and tljose around him are prejudiced, than on so many visions of
imagination ; and let him examine them with the same circumspec-
tion as if he were assured that they contain some truth among
much falsehood and many extravagances.^
Proceeding now to the second class of the Sources of Error,
1 See Leet. on Metaphysics, p. 63 et seq. — Ed. is, with some slight changes, taken from
2 1 Cor. iii. 18. Crousaz, Logique, t. ill., part ii., ch. 6, p. 263
3 This criticism of the precept of Descartes et uq. — Ed.
400 LOGIC. Lect. XXIX.
which are found in the Mind itself, I shall commence with the
following paragraph :
% XCIV. The Sources of Error which arise from the Con-
stitution, Habits, and Reciprocal Relations
Par. XCIV. II. Source i»^i ^^-i-- -ni- i
of Error arising from ^^ ^hc powcrs of Cognition, Feeling, and
the powers of cogni- Dcsire, may be subdivided into two kinds,
ion, ee mg, an e- rpj^^ g^.^^ of thcsc consists in the uuduc pre-
sire, — of two Kinds. i
ponderance of the Affective Elements of
mind (the Desires and Feelings) over the Cognitive; the sec-
ond, in the weakness or inordinate strength of some one or
other of the Cognitive Faculties themselves.
AiFection is that state of mind in which the Feelings and Desires
exert an influence not under the control of rea-
KxpHcation. gQ^ ; in Other words, a tendency by which the
1. Preponderance of • . n . • • j i • -x j ^ ai_' i
.„ . „ intellect is impeded in its endeavor to think an
Affection over Cogui- ^ ' _
tion. object as that object really is, and compelled
to think it in conformity with some view pre-
scribed by the passion or private interest of the subject thinking.
The human mind, when unruffled by passion, may be compared
to a calm sea. A calm '"sea is a clear mirror, in
Influence of Passion i-t-ii_ ji j* i-t-^i-i?
.. ... . which the sun and clouds, in which the forms
on the Mind. '
of heaven and earth, are reflected back pre-
cisely as tliey are presented. But let a wind arise, and the smooth,
clear surface of the water is lifted into billows and agitated into
foam. It no more reflects the sun and clouds, the forms of heaven
and earth, or it reflects them only as distorted and broken images.
In 'like manner, the tranquil mind receives and reflects the world
without as it truly is ; but let the wind of passion blow, and every
object is represented, not as it exists, but in the colore and aspects
and partial phases in which it pleases the sub-
Uoethjus quoted. '■ ^ .
ject to regard it. The state of passion and its
influence on the Cognitive Faculties are truly pictured by Boethius.'
" Nubibus atris Parqne serenls
Condita nullum Utuhi dicbus,
Fnnderc possunt Mox resoluto
Sidcm lumen. Soj-dida cocno,
Si marc volvcns Visibus obstat.
Turbidus austcr
Misccat acstum, Tu quoqiic si vis
Vitrea dudum, Lumino claro
1 De Consol. Phil., L. i , Metr 7- — Ko.
Lkct. XXIX. LOGIC. 401
Cernero verum, Spenique fugato,
Tramite recto Nee doloi- adsit,
Carpere callem : Nubila mens est,
Gaudia pelle, Vinctaque frenis,
Pelle timorem, Ha;c ubi regnant."
Every error consists in this, — that we take something for non-
existent, because we have not become aware of
Error limited to -^^ existence, and that, in place of this existent
Probable Keasoning. . ^
something, we fill up the premises of a probable
reasoning with something else.
I have here limited the possibility of error to Probable Reason-
ing, for, in Intuition and Demonstration, there is but little possi-
bility of important error. Hobbes indeed asserts that had it been:
contrary to the interest of those in authority, that the three angles
of a triangle should be equal to two right angles, this truth would
have been long ago proscribed as heresy, or as high treason.^ Tiiis
may be an ingenious illustration of the blind tendency of the pas-
sions to subjugate intelligence; but we should take it for more than
was intended by its author, were we to take it as more than an inge-
nious exaggeration. Limiting, therefore, error to probable inference
(and this constitutes, with the exception of a comparatively small -
department, the whole domain of human reasoning), we have to
inquire, How do the Passions influence us to the assumption of
false premises ? To estimate the amount of probability for or
against a given proposition, requires a tranquil, an unbiassed, a
comprehensive consideration, in order to take all the relative ele-
ments of judgment into due account. But this requisite state of
mind is disturbed when any interest, any wish, is allowed to
interfere.
% XCV. The disturbing Passions may be reduced to four :
Precipitancy, Sloth, Hope and Fear, Self—
Par. XCV. The Pas- t ." '1 '
sions, as sources of lOVC.
Error.- reduced to jo^ ^ Tcstlcss anxicty for a dccisiou be-
four. . . . •' .
gets impatience, which decides before the
preliminary inquiry is concluded. This is precipitancy.
2°. The same result is the eflect of Sloth, which dreams on
in conformity to custom, without subjecting its beliefs to the
test of active observation.
3°. The restlessness of Hope or F"ear impedes observation^
distracts attention, or forces it only on what interests the pas-
I Leviathan, Fart I. ch. 11. — £lX
51
402 LOGIC. Lkct. XXIX
sion ; — the sanguine looking on only what harmonizes with
his hopes, the diffident only on what accords with his fears.
4°. Self-love perverts our estimate of probability by causing
us to rate the grounds of judgment, not according to their real
influence on the truth of the decision, but according to their
bearing on our personal interests therein.
In regard to Impatience or Precipitation, — " all is the cause of
this which determines our choice on one side
Explication. rather than another. An imagination excites
1. Precipitancy. . .
pleasure, and because it excites pleasure we
yield ourselves up to it. We suppose, for example, that we are all
that we ought to be, and why? Because this supposition gives us
pleasure. This, in some dispositions, is one of the greatest obsta-
cles to improvement ; for he who entertains it, thinks there is no
necessity to labor to become what he is already. ' I believe,' says
Seneca,^ 'that many had it in their power to
have attained to wisdom, had they not been
impeded by the belief that wisdom they had already attained.'
'Multos puto ad sapientiam potuisse pervenire, nisi putassent se
pervenisse.' " ^ Erasmus gives the following as
Erasmus. i • • i & • /> i
the principal a«vice to a young votaiy oi learn-
ing in the conduct of his studies: "To read the most learned books,
to converse with the most learned men ; but, above all, never to
conceit that he himself was learned."'
"From the same cause, men flatter themselves with the hope of
dying old, although few attain to longevity.
Illustrations. mi i i i i i . .i ^ . •
Ihe less probable the event, the more certain
are they of its occurrence ; and why ? Because the imagination of
it is agreeable. ' Decrcpiti senes pnucorum annorum accesslonem
votis mendicant ; minores natu seipsos esse
From Seneca. _ ,..,.,,,. ,.
nngunt; mendacio sibi blandiuntur; et tarn ii-
benter fallunt, quam si fata una decipiant.'"* "Preachers," says
Montaigne, "are aware that the emotion which
From Montaigne. . , . , . . , ,
arises during their sennons animates themselves
to belief, and we are conscious that when roused to anger we apply
1 De Thinquillilnte Animi, c. 1. — Ed. doctos diligenter ediiiceret, deniqne si fe doc-
2 Crousaz, Logiqut, t. iil , part il. ch. 7, p. turn nunquam pntaret." Motto to G. J. Vos-
29". — Ed. sius, Opuscula de Studiorum linlicne. See
8 "Joannes Alexander Brassicanns rogavit Crenlus, Consiliaet Metkodus, etc., p. 686, 169i
Erasmum, qua ratione doctus posset fieri, — Ed.
respond it ex tempore: si doctis assidue con- 4 Seneca, De Brevitale Vita, ch. 11. Cron-
viveret, si doctos audiret non minus submisse saz, Logiqut^ t. iii. p. ii. oh. 7, p. 297, ed. 1T2&
quam honoriflce, ei doctos strenue legeret, si — Ed.
1
J.ECT. XXIX. LOGIC. 403
ourselves more intently to the defence of our thesis, and embrace it
with greater vehemence and approbation, than we did when our
mind was cool and unruffled. You simply state your case to an
advocate; he replies with hcvsitation and doubt; you are aware that
it is indifferent to him whether he undertakes the defence of the one
side or of the other ; but have you once fee'd him well to take your
case in hand ; he begins to feel an interest in it ; his will is ani-
mated. His reason and his science become also animated in pro-
portion. Your case presents itself to his understanding as a
manifest and indubitable truth ; he now sees it in a wholly dif-
ferent light, and really believes that you have law and justice on
your side."^ It is proper to observe that Montaigne was him-
self a lawyer, — he had been a counsellor of the Parliament of
Bordeaux.
It might seem that Precipitate Dogmatism and an inclination to
Skepticism were opposite characters of mind.
Precipitate Dogma- They are, howcver, closely allied, if not merely
lism and Skepticism, , /? .1 j- '.• fth.* • • j j
, ,, phases of the same disposition, ihis is indeed
phases of the same '■ '^
disposition. coufessed by the skeptic Montaigne.^ "The
most uneasy condition for me is to be kept in
suspense on urgent occasions, and to be agitated between fear and
^hope. Deliberation, even in things of lightest moment, is very
Itroublesome to me; and I find my mind more put to it, to undergo
|the various tumbling and tossing of doubt and consultation, than to
'set up its rest, and to acquiesce in whatever shall happen, after the
Mie is thrown. Few passions break my sleep ; but of deliberations,
lihe least disturbs me."
Precipitation is no incurable disease. There is for it one suni
and simple remedy, if properly applied. It is
tat^ir*^^ ^°' ^''"^'" °"^y required, to speak with Confucius, manfully
to restrain the wild horse of precipitancy by the
curb of consideration, — to weigh the reasons of decision, each and
I all, in the balance of cool investigation, — not to allow ourselves to
decide until a clear consciousness has declared these i-easons to be
true, — to be sufficient; and, finally, to throw out of account the
'Suffrages of self-love, of prepossession, of passion, and to admit
only those of reflection, of experience, and of evidence. This
remedy is certain and effectual. In theory it is satisfactory, but
its practical application requires a moral resolution, for the acquisi-
r tion of which no precept can be given.
In the secoiKJ place, " Sloth is likewise a cause of precipitation,
and it deserves the more attention as it is a cause of error extremely
1 Essais, L. ii. ch. 12. Quoted by Crousaz, I. c. — Ed. 2 Esaais, L. ii. c. 17. — Ed.
404 LOGIC. Lkct. XXIX
fiequent, and one of which we are ourselves less aware, and which
is less notorious to others. We feel it fatiguing
2. Sloth. . . . . , ^ ,
to continue an investigation, therefore we do
not pursue it ; but as it is mortifying to think that we have la-
bored in vain, we easily admit the flattering illusion that Ave have
succeeded. By the influence of this disposition it often happens,
that, after having rejected what first presented itself, — after having
rejected a second time and a third time what subsequently turned
up, because not sufficiently applicable or certain, we get tired of the
investigation, and perhaps put up with the fourth suggestion, which
is not better, haply even worse, than the preceding; and this
simply because it has come into the mind when more exhausted
and less scrupulous than it was at the conmiencement."^ "The
volition of that man," says Seneca, "is often
Seneca quoted. t i i i i . i
frustrated, who undertakes not what is easy, but
who wishes what he undertakes to be easy. As often as you
attempt anything, compare together yourself, the end which you
propose, and the means by which it is to be accomplished. For the
repentance of an unfinished work will make you rash. And here it
is of consequence whether a man be of a fervid or of a cold, of an
aspiring or of a humble, disposition." ^
To remedy this failing it is necessary, in conformity with this
advice of Seneca, to consult our forces, and the
^". tune we can afford, and the difficulty of the
subjects on which we enter. We ought to labor only at intervals,
to avoid the tedium and disquiet consequent on unremitted appli-
cation ; and to adjourn the consideration of any thought which
may please us vehemently at the moment, until the preposses-
sion in its favor has subsided with the animation which gave it
birth.
The two Causes of premature judgment — the affections of
Impatience and Sloth — being considered, I
3. Hope and Fear. .
pass on to the third principle of Passion, by
which the intellect is turned aside from the path of truth, — I
mean the disturbing influence of Hope and Fear. These passions,
though reciprocally contrary, determine a similar effect upon the
deliberations of the Underetanding, and are equally unfavorable for
the interest of truth. In forming a just conclusion upon a question
of probable reasoning, that is, where the grounds of decision are
not few, palpable, and of determinate effect, — and such questioi
1 Crousaz, Logique, t. iii. part ii. oh. 7, pt, 9 De Ira, L. iii, c. 7. Quoted by Crou8a%j
302. — Ed. Logiqut, t iii. p. 302. — Ed.
Lkct. XXIX. LOGIC. 406
may be said to be those alone on which differences of opinion may
arise, and are, consequently, those alone which require for their
solution any high degree of observation and ingenuity, — in such
questions hope and fear exert a very strong and a very unfavorable
influence. In these questions it is requisite, in the first place, to
seek out the premises ; and, in the second, to draw the conclusion.
Of these requisites the first is the more important, and it is also by
far the more difficult.
Now the passions of Hope and Fear operate severally to prevent
the intellect from discovering all the elements
How Hope and Fear of decision, which ought to be considered in
oj)erate unfavorably forming a coH'ect Conclusion, and cause it to
on the Understand- . i • . ^^i i i-ii
take into account those only which harmonize
with that conclusion to w-hich the actuating
passion is inclined. And here the passion operates in two ways.
In the first place, it tends so to determine the associations of
thought, that only those media of proof are suggested or called
into consciousness, which support the conclusion to which the
passion tends. In the second place, if the media of proof by
which a counter conclusion is supported are brought before the
mind, still the mind is influenced by the passion to look on their
reality with doubt, and, if such cannot be questioned, to undervalue
their inferential importance; whereas it is moved to admit, without
hesitation, those media of proof which favor the conclusion in the
interest of our hope or fear, and to exaggerate the cogency with
which they establish this result. Either passion looks exclusively
to a single end, and exclusively to the means by which that single
end is accomplished. Thus the sanguine temperament, or the
mind under the habitual * predominance of hope, sees only and
magnifies all that militates in favor of the wished-for consum-
mation, which alone it contemplates ; whereas the melancholic
temperament, or the mind under the habitual predominance of
fear, is wholly occupied with the dreaded issue, views only what
tends to its fulfilment, while it exaggerates the possible into the
probable, the probable into the certain. Thus it is that whatever
conclusion we greatly hope or greatly fear, to that conclusion we
are disposed to leap ; and it has become almost proverbial, that
men lightly believe both what they wish, and what they dread, to
bo true.
But the influence of Hope on our judgments, inclining us to find
whatever we wish to find, in so far as this arises from the illusion
of Self-love, is comprehended in this, — the fourth cause of Error,
— to which I now proceed.
41f6 LOGIC. Lect. XXIX-
Self-love, under which I include the dispositions of Vanity, Pride,
and, in general, all those which incline us to
4. Self-love. ', , • i . . .1
attribute an undue weight to those opinions in
which we feel a personal interest, is by far the most extensive and
influential in the way of reason and truth. In virtue of this princi-
ple, whatever is ours — whatever is adopted or patronized by us,
whatever belongs to those to whom we are attached — is either
gratuitously clothed with a character of truth, or its pretensions to
be accounted true are not scrutinized with the requisite rigor and
impartiality. I am a native of this country, and, therefore, not only
is its history to me a matter of peculiar interest, but the actions
and character of my countrymen are viewed in a very difierent
light from that in which they are regarded by a foreigner. I am
born and bred a member of a religious sect, and because they con-
stitute my creed, I find the tenets of this sect alone in conformity
to the Word of God. I am the partisan of a philosophical doc-
trine, and am, therefore, disposed to reject whatever does not har-
monize with my adopted system.
It is the part of a philosopher, says Aristotle, inasmuch as he is a
philosopher, to subjugate self-love, and to refute,
Aristotle, -his pre- -^ contrary to truth, not only the opinions of
his friends, but the doctrines which he himself
may have professed.* It is certain, however, that philosophera —
for philosophers are men — have been too often found to regulate
their conduct by the same opposite principle. That man pretended
to the name of philosopher, who scrupled not to
Illustrations of the declare that he would rather be in the wrong
influence of Self-love • 1 -r-^i 1 • i • 1 • i i •
on our opinions. "^^^^ ^^^^^ ^^^" 1" ^^^ light With his Oppo-
nents." "Gisbert Vo^tius urged Mersennus to
refute a work of Descartes a year before the book appeared, and
before he had himself the means of judging whether the opinions it
contained were right or wrong. A certain professor of philoso))hy
in Padua came to Galileo, and requested that he would explain to
him the meaning of the term parallaxis ; which he wished, he said,
to refute, having heard that it was opposed to Aristotle's doctrine
touching the relative situation of the comets. What! answered
Galileo, you wish to controvert a word the meaning of which you
do not know ! Redi tells us that a sturdy Peripatetic of his
acquaintance would never consent to look at the heavens through
a telescope, lest he should be compelled to admit the existence of
the new stars discovered by Galileo and othei-s. The same Redi
informs us that he knew another Peripatetic, a staunch advocate of
1 JEM. mc, 1. 4 (6). — Ed. « Cicero, lV*t. Qimbsi., i. 17.
i
Lect. XXIX. LOGIC. 407
the Aristotelian doctrine of equivocal generation (a doctrine, by
the way, which now again divides the physiologists of Europe), and
who, in particular, maintained that the green frogs which appear
upon a shower come down with the rain, who would not be
induced himself to select and examine one. of these frogs. And
Avhy? Because he was unwilling to be convicted of his error, by
Redi showing him the green matter in the stomach, and its feculae
in the intestines of the animal." ^ The spirit of the Peripatetic
philosophy was, however, wholly misunderstood by these mistaken
followers of Aristotle ; for a true Aristotelian is one who listens
rather to the voice of nature than to the precept of any master,
and it is well expressed in the motto of the great French anatomist,
— Riolanus est Peripateticus ; credit ea, et ea tantum, quae vidit.
From the same principle proceeds the abuse, and sometimes even
the persecution, which the discoverers of new truths encounter from
those who cherished opinions these truths subvert.
In like manner, as we are disposed to maintain our own opinion,
we are inclined to regard with favor the opin-
Self-love leads us to . ^ '■
regard with favor the ^^"S of thosc to whom we are attached by love,
opinions of those to gratitude, and Other conciliatory affections. "We
xvhom we are in any ^^ ^^^^ j^j^j^ q^. attachment to the pcrsous of
way attached. „ . , , . . n i
our iriends, — we love m a certam sort all that
belongs to them ; and as men generally manifest sufficient ardor in
support of their opinions, we are led insensibly by a kind of sym-
pathy to credit, to approve, and to defend these also, and that even
more passionately than our friends themselves. We bear affection
to others for various reasons. The agreement of tempers, of incli-
nations, of pursuits ; their appearance, their manners, their virtue,
the partiality which they have shown to us, the services we have
received at their hands, and many other particular causes, determine
and direct our love.
"It is observed by the great Malebranche,^ that if any of our
friends, — any even of those we are disposed
a e ranciie a - ^^ love, — advance an opinion, we forthwith
duced to this effect. . '
lightly allow ourselves to be persuaded of its
truth. This opinion we accept and support, without troubling our-
selves to inquire whether it be conformable to foct, frequently even
against our conscience, in conformity to the darkness and confusion
1 Reimarus, p. 389. [Die VernunftUhre, von published in 1756. The above four anecdotes
H. S. R. (Hermann Samuel Reimarus), are all taken from this work. — Ed.]
dritte Auflage, Hamburg, 1766, § 332. First 2 Recherche dt la Verite, L. iv. ch. 13. — Ed.
408 LOGIC. Lect. XXnL
of our intellect, to the corruption of our heart, and to the advan-
tages which we hope to reap from our facility and comphiisance."^
The influence of this principle is seen still more manifestly Avhen
the passion changes ; for though the things
rius ghown egpe- themselves remain unaltered, our judgments
ciallv when the pas- . , , i tt
sion " chauees concernmg them are totally reversed. How
often do we behold persons who cannot, or will
not, recognize a single good quality in an individual from the mo-
inent he has chanced to incur their dislike, and who are even ready
to adopt opinions, merely because opposed to others maintained by
the object of their aversion? The celebrated
Arnault! iioids that Arnauld " gocs SO far even as to assert, that men
man isnaturaJIv euvi- . i . i , . . . ,
^^^ ' are natui'ally envious and jealous; that it is with
pain they endure the contemplation of othera in
the enjoyment of advantages which they do not themselves possess;
and, as the knowledge of truth and the power of enlightening man-
kind is of one of these, that they have a secret inclination to de-
prive them of that glory. This accordingly often determines them
to controvert without a ground the opinions and discoveries of
others. Sell-love accordingly often argues thus : — ' This is au
opinion which I have originated, this is an opinion, therefore, which
is true;' whereas the natural malignity of man not less frequently
suggests such another: ' It is another than I who has advanced this
doctrine ; this doctrine is, therefore, false.'
We may distinguish, however, from malignant or envious contra-
diction another passion, which, though more
e ove o ispu- generous in its nature and not simply a mode of
Self-love, tends, nevertheless, equally to divert
ns from the straight road of truth, — I mean Pugnacity, or the love
of Disputation. Under the influence of this passion, we propose
as our end victory, not truth. We insensibly become accustomed
to find a reason for any opinion, and, in placing ourselves above all
reasons, to surrender our belief to none. Thus it is why two dis-
putants so rarely ever agree, and why a question is seldotn or never
decided in a discussion, where the combative dispositions of the rea-
soners have once been roused into activity. In controversy it is
always easy to find wherewithal to reply; the end of the parties is
not to avoid erroi", but to impose silence ; and they are less ashamed
of continuing wrong than of confessing that they are not right.' ••
1 Vtiro,IfouvtlU Logiqut, part ii., ch. viii., p. 3 V Art de Ptntrr, p. iii. ch. 20. Cf. CarCk
288. — Ed. NouveUe Logiqut, part ii., ch. 9, p. 811, Pari*
2 /,' Art de Ptnser {Port Royal Logic), p. iii. 1820. — Ed.
efa. 20. — Ed.
Lkct. XXIX.
LOGIC,
409
These affections the
immediate causes of
all error.
rieliminary condi-
tions requisite for tlie
efficiency of precepts
against the sources of
error.
These affections may be said to be the immediate causes of all
error. Other causes there are, but not immedi-
ate. In so far as Logic detects the sources of
our false judgments and shows their remedies,
it must carefully inculcate that no precautionary
precept for particular cases can avail, unless the
inmost principle of the evil be discovered, and
a cure applied. You must, therefore, as you
would remain free from the hallucination of
fjilse opinion, be convinced of the absolute necessity of following
out the investigation of every question calmly and without passion.
You must learn to pursue, and to estimate, truth without distraction
or bias. To this there is required, as a primary condition, the un-
shackled freedom of thought, the equal glance which can take in
the whole sphere of observation, the cool determination to pursue
the truth whithersoever it may lead ; and, what is still more impor-
tant, the disposition to feel an interest in truth and in truth alone.
If perchance some collateral interest .may first prompt us to the
inquiry, in our general interest fortnith we must repress, — we must
forget, this interest, until the inquiry be concluded. Of what
account are the most venerated opinions if they be untrue ? At
best they are only venerable delusions. He who allows himself to
be actuated in his scientific procedure by any partial interest, can
never obtain a comprehensive survey of the whole he has to take
into account, and always, therefore, remains incapable of discrimi-
nating, with accuracy, error from truth. The independent thinker
must, in all his inquiries, subject himself to the genius of truth, —
must be prepared to follow her footsteps without faltering or hesita-
tion. In the consciousness that truth is the noblest of ends, and
that he pursues this end with honesty and devotion, he will dread
no consequences, — for he relies upon the truth. Does he compass
the truth, he congratulates himself upon his success ; does he fall
short of its attainment, he knows that even his present failure will
ultimately advance him to the reward he merits. Err he may, and
that perhaps frequently, but he will never deceive himself We
cannot, indeed, rise superior to our limitary nature, we cannot,
therefore, be reproached for failure ; but we are always responsible
for the calnjness and impartiality of our researches, and these alone
render us worthy of success. But though it be manifest, that to
attain the truth we must follow whithersoever the truth may lead,
still men in general' are found to yield not an absolute, but only a
restricted, obedience to the precept. They capitulate, and do not
unconditionally surrender. I give up, but my cherished dogma in
52
410 LOGIC. Lect. XXIX.
religion must not be canvassed, says one ; — my political principles
are above inquiry, and must be exempted, says a second ; — my
country is the land of lands, this cannot be disallowed, cries a thii-d;
— my order, my vocation, is undoubtedly the noblest, exclaim a
fourth and fifth ; — only do not require that we should confess our
having erred, is the condition which many insist on stipulating.
Above all, that resolve of mind is difficult, which is ready to sur-
render all fond convictions, and is prepared to recommence investi-
gation the moment that a fundamental error in the foriner system
of belief has been detected. These are the principal grounds why,
among men, opinion is so widely separated from opinion ; and why
the clearest demonstration is so frequently for a season frustrated
of victory.
Par. xcvi. Holes ^ XCVI. Agaiust the Errors which arise
against Errors from from the Affcctions, there may be given
the Affections. ^y^^ ^^^.^^ following rulcs :
1°. When the error ,has arisen from the influence of an
active affection, the decisive judgment is to be annulled ; the
mind is then to be freed, as far as possible, from passion, and
the process of inquiry to be recommenced as soon as the requi-
site tranquillity has been restored.
2°. When the error has arisen from a relaxed enthusiasm for
knowledge, we must reanimate this interest by a vivid repre-
sentation of the paramount dignity of truth, and of the lofty
destination of our intellectual nature.
3°. In testing the accuracy of our judgments, we must be
particularly suspicious of those results which accprd with our
private inclinations and predominant tendencies.
These rules require no comment.
LECTURE XXX,
MODIFIED STOICHEIOLOaY.
SECTION II.— ERROR— ITS CAUSES AND REMEDIES.
B. — AS IN THE COGNITIONS, FEELINGS, AND DESIRES.
II. — WEAKNESS AND DISPROPORTIONED STRENGTH OF THE
FACULTIES OF KNOWLEDGE.
I NOW go on to the Second Head of the class of Errors founded
on the Natural Constitution, the Acquired Hab-
Weakness and Dis- j^g^ ^j^d the Reciprocal Relations of our Cogni-
propor lone treng ^j^^ ^^^ AiFective Powers, that is, to the Causes
of the Faculties of ....
Knowledge. of Error which originate in the Weakness or
Disproportioned Strength of one or more of
our Faculties of Knowledge themselves.
Here, in the first place, I might consider the errors which have
arisen from the Limited Nature of the Human
Neglect of the Lim- Intellect in general, — or rather from the mis-
ited Nature of the ,-, iiii t. ii-r-i t_
^ , „ , takes that have been made by philosophers m
Human Intellect a _ ^ ... .
source of error. denying or not taking this limited nature into
account.^ The illustration of this subject is one
which is relative to, and supposes an acquaintance with, some of
the abstrusest speculations in Philosophy, and ■which belong not to
Logic, but to Metaphysics, I shall not, therefore, do more than
simply indicate at present, what it will be proper at another season
fully to explain. It is manifest, that, if the
. losop yo e human mind be limited, — if it only knows as
Absolute. ...
it is conscious, and if it be only conscious, as it
is conscious of contrast and opposition, — of an ego and non-ego, —
if this supposition, I say, be correct, it is evident that those philoso-
phers are in error, who virtually assume that the human mind is
1 [On this subject see Crusjus.] [Christian verldssigkeit der menschlichen Erkenntniss, $ 443,
August Crusius, Weg zur Gewissheit und Zu- 1st ed. 1747. — Ed-
412 LOGIC. Lect. XXX.
unlimited, that is, that the human mind is capable of a knowledge
superior to consciousness, — a cognition in which knowledge and
existence — the Ego and non-Ego — God and the creature — are
identical ; that is, of an act in which the mind is the Absolute, and
knows the Absolute. This philosophy, the statement of which, as
here given, it would require a long commentary to make you under-
stand, is one which has for many years been that dominant in Ger-
many ; it is called the Philosophy of the Absolute, or the Philoso-
phy of Absolute Identity. This system, of which Schelling and
Hegel are the great representatives, errs by denying the limitation
of human intelligence without proof, and by boldly building its
edifice on this gratuitous negation.^
But there are other forms of philosophy which err not in actually
postulating the infinity of mind, but in taking
2. A one-sided view ^^-^^ j^ one-sided view of its finitude. It is a
of the finitude of i /. , i • i ^ ^
^^^^ general tact, which seems, however, to have
escaped the observation of philosophers, that
whatever we can positively compass in thought, — whatever we can
conceive as possible, — in a word, the omne cogitabile, lies between
two extremes or poles, contradictorily opposed, and one of which
must consequently be true, but of neither of which repugnant oppo-
sites are we able to represent to our mind the possibility .'^ To take
one example out of many : we cannot construe
iiiurtrfttcd by refer. ^^ ^^^ ^.^^ ^^ possiblc the absolutc commcncc-
ence to the two con- « • i
tradictorie8,-theab- "^^nt of time; but wc are equally unable to
solute commencement, think the possibility of the counter alternative,
and the iniinite nou- — jjg infinite or absolute non-commencement, in
commenceme&t of ., t .^ • t* •, f .• -v-r
.pjjj^^ other words, the mnmte regress of time. Now
it is evident, that, if we looked merely at the
one of these contradictory opposites and argued thus : whatever is
inconceivable is impossible, the absolute commencement of time is
inconceivable, therefore the absolute commencement of time is
impossible; but, on the principles of Contradiction and Excluded
Middle, one or other of the two opposite contradictories must be
true ; therefore, as the absolute commencement of time is impossi-
ble, the absolute or infinite non-commencement of time is neces-
t?ary: — I say, it is evident that this reasoning would be incompe-
tent and one-sided, because it might be converted ; for, by the same
one-sided process, the opposite conclusion might be drawn in favor
of the absolute commencement of time.
1 See Discussions^ p. 19. — Ed.
3 See Discussions, p. 601 et seq., Lectures on Metapkysies, p. S27 et uq. — Ex>.
Lkct. XXX. LOGIC. 413
Now, the unilateral and incompetent reasoning which I have here
supposed in the case of time, is one of which
^ ,^^™^ pnncip e ^^^ Necessitarian is guilty in his arfjument to
exemplified in the case ^ ... . .
of the Necessitarian prove the impossibility of human volltions being
Argument against the free. He correctly lays down, as the foundation
Freedom of the Hu- ^£ j^j^ reasoning, two propositions which must
at once be allowed : 1°, That the notion of the
liberty of volition involves the supposition of an absolute com-
mencement of volition, that is, of a volition which is a cause, but is
not itself, qua cause, an effect. 2°, That the absolute commence-
ment of a volition, or of aught else, cannot be conceived, that is,
cannot be directly or positively thought as possible. So far he is
correct ; but when he goes on to apply these principles by arguing
(and be it observed this syllogism lies at the root of all the reason-
ings for necessity). Whatever is inconceivable is impossible ; but the
supposition of the absolute commencement of volition is inconceiva-
ble,' therefore^ the sxipp)osition of the absolute commencement of
volition {the condition of free will) is impossible, — we may here
demur to the sumption, and ask him, — Can he positively conceive
the opposite contradictory of the absolute commencement, that is,
an infinite series of relative non-commencements? If he answers,
as he must, that he cannot, we may again ask him, — By what right
he assumed as a self-evident axiom for his sumption, the proposition,
— that lohatever is inconceivable is im.possible, or by Avhat right he
could subsume his minor premise, when by his own confession he
allows that the opposite contradictory of his minor premise, that is,
the very proposition he is apagogically proving, is, likewise, incon-
ceivable, and, therefore, on the principle of his sumption, likewise
impossible.
The same inconsequence would equally apply to the Libertarian,
who should attempt to prove that free-will must
And in the case of be allowed, ou the ground that its contradictory
the Libertarian Arcu- 'j. • • -i i i • • i i
^ . , , ,„ „ opposite IS impossible, because inconceivable.
ment in behalf of ^ ^ . .
Free-will. He cannot prove his thesis by such a process;
in fact, by all speculative reasoning from the
conditions of thought, the two doctrines are in mqiiilibrio ; — both
are equally possible, — both are equally inconceivable. It is only
when the Libertarian descends to arguments drawn from the fact
of the Moral Law and its conditions, that he is able to throw in
reasons which incline the balance in his favor.
On these matters, I however, at present, only touch, in order to
show you under what head of Error these reasonings would natu
rally fall.
414
LOGIC.
Lect. XXX
Weakness or di?pro-
portioned strength of
the several Cognitive
Faculties, — a source
of Error.
Cognitive Faculties
of two classes, a Lower
and a Higher.
Leaving, therefore, or adjourning, the consideration of the imbe-
cility of the human intellect in general, I shall
now take into view, as a source of logical error,
the Weakness or Disproportioned Strength of
the several Cognitive Faculties. Now, as the
Cognitive Faculties in man consist partly of
certain Lower Powers, which he possesses in
common Avith other sensible existences, namely,
the Presentative, the Retentive, the Representa-
tive and the Reproductive Faculties, and partly of certain Higher
Powers, in virtue of which he enters into the rank of intelligent
existences, namely, the Elaborative and Regulative Faculties, — it
will be proper to consider the powers of these two classes severally
in succession, in so far as they may afford the causes or occasions
of error.
Of the lower class, the first faculty in order is the Presentative
or Acquisitive Faculty. This, as you remember,
is divided into two, viz., into the faculty which
presents us with the phenomena of the outer
world, and into the foculty which presents us
with the phenomena of the inner.^ The former is External Per-
ception, or External Sense ; the latter is Self-consciousness, Inter-
nal Perception, or Internal Sense. I commence, therefore, with the
Faculty of Extenial Perception, in relation to which I give you the
following paragraph.
L The Lower Class,
— 1. The Presentative
Faculty.
1 XCVII. When aught is presented through the outer
senses, there are two conditions necessary
Par. xcvn. (a) Ex- f^j. j^g j^dequatc perception : — 1% The rela-
temal Perception, — ^ n i i
a8 a source of Error. tivc OrgQus must be prcscut, and in a con-
dition to discharge their functions ; and 2°,
The Objects themselves must bear a certain relation to these
organs, so that the latter shall be suitably affected, and thereby
the former suitably apprehended. It is possible, therefore,
that, partly through the altered condition of the organs, partly
through the altered situation of the objects, dissimilar pre-
sentations of the same, and similar presentations of different,
objects, may be the result.*
"In the jBrst place, without the organs specially subservient to
1 See Lectures on MetapAysi'cs,p. 282 et seq. — Ed. Kouvelle Logique, part ii. ch. rl. p. 278. Bacb
* Krug, Logik, i 1. 83. — Ed. [Cf. Caro, mann, Logik, i 407, p. 668.1
Lect. XXX. LOGIC. 415
External Pei'ception, — without the eye, the ear, etc., sensible per-
ceptions of a precise and determinate character,
Explication. Ruch, for example, as color or sound, are not
Conditions of the ^ . . r xi i i x
^. .^ „ competent to man. In the second place, to per-
adequate activity of ^ .
External Perception. form their functions, these organs must be in
a healthy or normal state; for if this condition
be not fulfilled, the presentations which they furnish are null, incom-
plete, or false. But, in the third place, even if the organs of sense
are sound and perfect, the objects to be presented and perceived
must stand to these organs in a certain relation, — must bear to
them a certain proportion; for, otherwise, the objects cannot be pre-
sented at all, or cannot be perceived without illusion. The sounds,
for example, which we are to hear, must neither be too high nor too
low in quality ; the bodies which we are to see, must neither be too
near nor too distant, — must neither be too fee-
0K81 e 1 usjons o ^^j ^^j. ^^^ intensely illuminated. In relation
the Senses. '' . • ,
to the second condition, there are given, in con-
sequence of the altered state of the organs, on the one hand, differ-
ent presentations of the same object; — thus to a person who has
waxed purblind, his friend appears as an utter stranger, the eye
now presenting its objects with less clearness and distinctness. On
the other hand, there are given the same, or undistinguishably simi>
lar, presentations of different objects; — thus to a person in the
jaundice, all things are presented yellow. In relation to the third
condition, from the altered position of objects, there are, in like
manner, determined, on the one hand, different presentations of the
same objects, — as when the stick which appears straight in the air
appears crooked ^h en partially immersed in water; and, on the
other hand, identical presentations of different objects, as when sx
man and a horse appear in the distance to be so similar, that thb
one cannot be discriminated from the othex\ In all these cases,
these illusions are determined, — illusions which may easily become
the occasions of false judgments."^
"In regard to the detection of such illusions and obviating the
error to which they lead, it behooves us to take
Precautions with a i /- n • ,• -»tt ^ • ^l
, ^, . » ,. the followmg precautions. We must, m the
view to the detection => ^ '
of illusions of the fii'st placc, examine the state of the organ. If
Senses, and obviating found defective, wc must endcavor to restore it
the errors to which ^^ perfection ; but if this cannot be done, we
they lead. ^ / r -u
must ascertain the extent and nature of tna
evil, in order to be upon our guard in regard to quality and degree
of the false presentation.
1 Krug, Logik, i 138. Anm. — £•».
416 LOGIC. Lect. XXX
" In the second place, we must examine the relative situation of
the object, and if this be not accommodated to the organ, we must
either obviate the disproportion and remove the media which occa-
sion the illusion, or repeat the observation under different circum-
stances, compare these, and thus obtain the means of making an
ideal abstraction of the disturbing causes." *
In regard to the other Presentative Faculty, — the Faculty of
Self-consciousness, — Internal Perception, or Internal Sense, as we
know less of the material conditions whicli modify its action, we
are unable to ascertain so precisely the nature of the illusions of
which it may be the source. In reference to this subject you may
take the following paragraph.
% XCVIII. The faculty of Self-consciousness, or Internal
Sense, is subject to various changes, which
Par. xcnn. (b) either modify our apprehensions of objects,
Self-oonsoiousness, — ._ , .,., .,
aa a source of Error. <>>" uiflucnce the manner HI which we judge
concerning them. In so far, therefore, as
felse judgments are thus occasioned. Self-consciousness is a
source of error.*
It is a matter of ordinary observation, that the vivacity with
which we are conscious of the various phenom-
Expiication. ^^^ ^f p^j^d, differs not only at different times,
Sclf-coiisciousncss
varies in intensity. ^" different States of health, and in different de-
grees of mental freshness and exhaustion, but, at
the same time, differs in regard to the different kinds of these phe-
nomena themselves. According to the greater (^" less intensity of
this faculty, the same thoughts of which we are conscious are, at
one time, clear and distinct, at another, obscure and confused. At
one time we are almost wholly incapable of reflection, and every
act of self-attention is forced and irksome, and differences the most
marked pass unnoticed ; while, at another, our self-consciousness is
alert, all its applications pleasing, and the most faint and fugitive
phenomena arrested and observed. On one occasion, self-conscious-
ness, as a reflective cognition, is strong ; on another, all reflection is
extinguished in the intensity of the direct consciousness of feeling
or desire. In one state of mind our representations are feeble ; in
another, they are so lively that they are mistaken for external reali-
ties. Our self-consciousness may thus be the occasion of frequent
error ; for, according to its various modifications, we may form the
most opposite judgments concerning the same things, — pronouno-
1 Krug, Losik, j 166. — Ed. « Knig, Logik, J 139. — Ed.
Lect. XXX. LOGIC. 417
ing them, for example, now to be agreeable, now to be disagreeable,
according as our Internal Sense is variously affected.
The next is the Retentive or Conservative Faculty, — Memory
Btrictly so called ; in reference to which I give you the following
paragraph.
% XCIX. Memory, or the Conservative Faculty, is the
occasion of Error, both when too weak and
Par. XCIX. 2. Mem- whcu too stroug. Whcu too wcak, the
ory, — as a soupae of , , „ , . i • i • , . •
j,j,ygp complement oi cognitions which it retains
is small and indistinct, and the Under-
standing or Elaborative Faculty is, consequently, unable ade-
quately to judge concerning the similarity and differences
of its repi'csentations and concepts. When too strong, the
Understanding is overwhelmed with the multitude of acquired
cognitions simultaneously forced upon it, so that it is unable
calmly and deliberately to compare and discriminate these.'
That both these extremes, — that both tlie insufficient and the
supei-fluous vigor of the Conservative Faculty
Explication. ,, , /. . .„
are severally the sources or error, it will not
require many observations to make apparent.
In regard to a feeble memory, it is manifest that a multitude of
false judgments must inevitably arise from an
Feeble memory. . ..,.„, , ,
incapacity in this faculty to preserve the obser-
vations committed to its keeping. In consequence of this incapac-
ity, if a cognition be not wholly lost, it is lost at least in part, and
the circumstances of time, place, persons and things confounded
with each other. For example, — I may recollect the tenor of a
passage I have read, but from defect of memory may attribute to-
one author what really belongs to another. Thus a botanist may
judge two different plants to be identical in species, having for-
gotten the differential characters by which they were discriminated ;.
or he may hold the same plant to be two different species, having
examined it at different times and places.-
Though nothing could be more erroneous than a general and
unqualified decision, that a great memory is-
Strong memory. . ^ -, . ^ ■
incompatible with a sound judgment, yet it
is an observation confirmed by the experience of all ages and coun-
tries, not only that a great memory is no condition of high intellect-
ual talent, but that great memories are very frequently found in com-
1 [Cf. Bacbmann, Logik, i 408.] 3 Krng, Logik, i 141. Anm. — Ed,
53
418
LOGIC.
Lect. XXX.
bination with comparatively feeble powers of thought.^ The truth
seems to be, that where a vigorous memory is conjoined with a
vigorous intellect, not only does the force of the subsidiary faculty
not detract from the strength of the principal, but, on the contrary,
tends to confer on it a still higher power; whereas when the infe-
rior faculty is disproportionately strong, that so' far from nourishing
and corroborating the superior, it tends to reduce this faculty to a
lower level than that at which it would have stood, if united with
a less overpowering subsidiary. The greater the magazine of vari-
ous knowledge which the memory contains, the better for the un-
derstanding, provided the understanding can reduce this various
knowledge to order and subjection. "A great memory is the prin-
cipal condition of bringing before the mind many different repre-
sentations and notions at once, or in rapid succession. This simul-
taneous or nearly simultaneous presence disturbs, however, the
tranquil comparison of a small number of ideas, which, if it shall
judge aright, the intellect must contemplate with a fixed and steady
attention."^ Now, where an intellect possesses the power of concen-
tration in a high degree, it will not be harassed in its meditations
by the officious intrusions of the subordinate faculties, however vig-
orous these in themselves may be, but will control their vigor by ex-
hausting in its own operations the whole applicable energy of mind, 'j
Whereas where the inferior is more vigorous than the superior, it will,
in like manner, engross in its own function the disposable amount of
activity, and overwhelm the principal faculty with materials, many
even in proportion as it is able to elaborate few. This appears to me
the reason why men of strong memories are so often men of propor-
tionally weak judgments, and why so many errors arise from the
possession of a faculty, the perfection of which ought to exempt]
them from many mistaken judgments.
As to the remedy for these opposite extremes. The former —
the imbecility of Memory — can only be allevi-
ated by invigorating the capacity of Retention |
through mnemonic exercises and methods ; the
latter, — the inordinate vigor of Memory, — by cultivating the
Understanding to the neglect of the Conservative Faculty. It
will, likewise, be necessary to be upon our guard against the errors
originating in these counter sources. In the one case distrusting
the accuracy of facts, in the other, the accuracy of their elaboration.* j
The next faculty is the Reproductive. This, when its operation
Remedies for these
opposite extremes.
1 Compare Lecturet on Metaphysics, p. 424. — quoted by Stewart, Mem., Part iii. ch. i. sect
Ed vi. ColUeted Works, vol. iv.p.249i
2 Diderot. Ltttrt nr **s Sourds tt Muets, » C(. Krug, Loeik, ^ 16& Anm. — Eix
Lkct. XXX. I.GGIC. ' 419
is voluntarily exerted, is called Recollection ov Jteminiscence ; when
it energizes spontaneously or without volition, it
3. The Reproductive j^ ^.^jj^^^ Suoqestion. The laws by which it is
Faculty. , . . , , . ,, . ,
governed in either case, but especially in the
latter, are called the Laws of Mental Association. This Repro-
ductive Faculty, like the Retentive, is the cause of error, both if its
vigor be defective, or if it be too strong. I sliall consider Recollec-
tion and Suggestion severally and apart. In regard to the former I
give you the following paragraph,
^ C. The Reproductive Faculty, in so far as it is volunta-
rily exercised, as Reminiscence, becomes a
par.c. (a)Reminis. soUTCc of EiToi', as it is either too slug-
cence, — as a source of . . , ^ i t->
jjrror. g^^" or too pi'onipt, precisely as the Re-
tentive Faculty, combined with which it
constitutes Memory in the looser signification.
It is necessary to say very little in special reference to Reminis-
cence, for what was said in regard to the Con-
Explication. servative Faculty or Memory Proper in its
Reminiscence, — its •, • ^ . • tiix :i • r ^
undue activity. highest vigor, was applicable to, and in fact
supposed a corresponding degree of, the Re-
productive. For, however great may be the mass of cognitions
retained in the mind, that is, out of consciousness but potentially
capable of being called into consciousness, these can never of them-
selves oppress the Understanding by their simultaneous crowding
or rapid succession, if the faculty by which they are revoked into
consciousness be inert ; whereas if this revocative faculty be com-
paratively alert and vigorous, a smaller magazine of retained cogni-
tions may suffice to harass the intellect with a ceaseless supply of
materials too j^rofuse for its capacity of elaboration.
On the other hand, the inactivity of our Recollection is a source
of error, precisely as the weakness of our Mem-
ory proper ; for it is of the same effect in rela-
tion to our judgments, whether the cognitions requisite for a deci-
sion be not retained in the mind, or whether, being retained, they
are not recalled into consciousness by Reminiscence.
In regard to Suggestion, or the Reproductive Faculty operating
spontaneously, that is, not in subservience to an act of Will, — I
shall give you the following paragraph.
% CI. As our Cognitions, Feelings, and Desires are con-
nected together by what are called the Laws of Association,
420 ^ LOGIC. Lect. XXX
and as each link in the chain of thought suggests or awakens
into consciousness some other in conformity
Par. CI. (b) sugges- ^q thcse Laws, — thesc Laws, as they be-
tion,— as a source of ...
Error. stow a Strong subjective connection on
thoughts and objects of a wholly arbitraFy
union, frequently occasion great confusion and error in our
judgments.
*
" Even in methodical thinking, we do not connect all onr
thoughts intentionally and rationally, but many
Explication. ° \ . .,. "^
press forward into the tram, either m conse-
quence of some external impression, or in virtue of certain internal
relations, which, however, are not of a logical dependency. Thus,
thoughts tend to suggest each other, which have reference to things
of which we were previously cognizant as coexistent, or as immedi-
ately consequent, which have been apprehended as bearing a resem-
blance to each other, or which have stood together in reciprocal
and striking contrast. This connection, though precaiious and
non-logical, is thus, however, governed by certain laws, which have
been called the Laws of Association^ * These laws, which I have
just enumerated, viz., the Law of Coexistence or Simultaneity, the
Law of Continuity or Immediate Succession, the Law of Similarity,
and the Law of Contrast, are all only special modifications of one
general law, which I would call the Law of Redintegration ;^ that
is, the principle according to which whatever has previously formed
a part of one total act of consciousness, tends, when itself recalled
into consciousness, to reproduce along with it the other parts of
that original whole. But though these tendencies be denominated
Imos^ the influence which they exert, though often strong and somo-
times irresistible, is only contingent ; for it frequently happens that
thoughts which have previously stood to each other in one or other
of the four relations do not suggest each other. The Laws of
Association stand, therefore, on a very different footing from the
laws of logical connection. But those Laws of Association, contin-
gent though they be, exert a great and often a very pernicious
influence upon thought, inasmuch as by the involuntary intrusion
of representations into the mental chain which are wholly irrele-
vant to the matter in hand, there arises a perplexed and redundant
tissue of thought, into which false characters niny easily find admis-
sion, and in which true characters may easily be overlooked.' But
t Krng, Logik, f 144. Anra. — Ed. > See Lect. on Metaphysics, p. 481 cl leq. — Kd-
3 Krug, Logik, i 144. Anm. — £i>.
I
LkgT. XXX LOGIC. 421
this is not all. For, by being once blended together in our con-
seiousness, things really distinct in their nature tend again naturally
to reassooiate, and, at every repetition of this conjunction, this ten-
dency is fortified, and their mutual suggestion rendered more cer-
tain and irresistible.
It is in virtue of this principle of Association and Custom, that
things are clothed by us with the precarious attri-
inflnence of Asso butcs of deformity or beauty ; and some philos-
eiatioD in matters of , , /> ' • • i ,
-. ophers have gone so far as to mamtain that our
principles of Taste are exclusively dependent
on the accidents of Association. But if this be an exaggeration, it
is impossible to deny that Association enjoys an extensive jurisdic-
tion in the empire of taste, and, in particular, that fashion is almost
wholly subject to its control. .
On this subject I may quote a few sentences from the first volume
of Mr. Stewart's Elements. "In matters of
Stewart quoted. i /*. . • i . t
laste, the effects which we consider are pro-
duced on the mind itself^ and are accompanied either with pleasure
or with pain. Hence the tendency to casual association is much
stronger than it commonly is with, respect to physical events ; and
when such associations are once formed, as they do not lead to any
important inconvenience, similar to those which result from phys-
ical mistakes, they are not so likely to be corrected by mere experi-
ence, unassisted by study. To this it is owing that the influence
of association on our judgments concerning beauty and deformity,
is still more remarkable than on our speculative conclusions; a cir-
cumstance which has led some philosophers to suppose that associa-
tion is sufficient to account for the origin of these notions, and that
there is no such thing as a standard of taste, founded on the princi-
ples of the human constitution. But this is undoubtedly pushing
the theory Ji great deal too far. The association of ideas can never
account for the origin of a wo^^ notion, or of a pleasure essentially
<lifferent from all the others which we know. It may, indeed,
enable us to conceive how a thing indifferent in itself may become
a source of pleasure, by being connected in the mind with some-.
thing else which is naturally agreeable ; but it presupposes, ift
every instance, the existence of those notions and those feelings
which it is its province to combine ; insomuch that, I apprehend, it
will be found, wherever association produces a change in our judg-
ihents on matters of taste, it does so by cooperating with some n:;:-
ural i)rinciple of the mind, and implies the existence of certaia
original sources of pleasure and uneasiness.
"A mode of dress, which at first appeared awkward, acquires, in
422 LOGIC. Lect. XXX.
a few weeks or months, the appearance of elegance. By being
accustomed to see it worn by those whom we consider as models
of taste, it becomes associated with the agreeable impressions
which we receive from the ease and grace and refinement of their
manners. When it pleases by itself, the effect is to be ascribed,
not to the object actually before us, but to the impressions with
which it has been generally connected, and which it naturally
recalls to the mind.
"This observation points out the cause of the perpetual vicissi-
tudes in dress, and in everything whose chief recommendation
arises from fashion. It is evident that, as fir as the agreeable effect
of an ornament arises from association, the effect will continue only
while it is confined to the higher orders. When it is adopted by
the multitude, it not only ceases to be associated with ideas of
taste and refinement, but it is associated with ideas of affectation,
absurd imitation, and vulgarity. It is accordingly laid aside by the
higher orders, who studiously avoid every circumstance in external
appearance which is debased by low and common use ; and they
are led to exercise their invention in the introduction of some new
peculiarities, which firet become fiishionable, then common, and last
of all, are abandoned as vulgar." '
"Our moral judgments, too, may be modified, and even perverted
to a certain degree, in consequence of the operation of the same
principle. In the same manner in which a pereon who is regarded
as a model of taste may introduce, by his example, an absurd or
fantastical dress ; so a man of splendid virtues may attract some
esteem also to his imperfections ; and, if placed in a conspicuous
situation, may render his vices and follies objects of general imita-
tion among the multitude.
"'In the reign of Charles II.,' says Mr. Smith,* 'a degree of licen-
tiousness was deemed the characteristic of a liberal education. It
was connected, according to the notions of those times, with gen-
erosity, sincerity, magnanimity, loyalty; and proved that the person
who acted in this manner was a gentleman, and not a puritan. Se-
verity of manners, and regularity of conduct, on the other hand,
were altogether unfashionable, and were connected, in the imagina-
tion of that age, with cant, cunning, hypocrisy, and low mannere.
To superficial minds the vices of the great seem at all times agree-
able. They connect them not only with the splendor of fortune,
but with many superior virtues which they ascribe to their superiors;
I EUmentt, vol. i., Part i. chap. r. CoUttUd « ntory of Moral Sentiments, Part t. o. 2. —
Works, ii. p. 322 tt srq. £d.
LiXT. XXX. LOGIC. 428
with the spirit of freedom and independency ; with frankness, gen-
erosity, humanity, and politeness. The virtues of the inferior ranks
of people, on the contrary, — their parsimonious frugality, their
painful industry, and rigid adherence to rules, seem to them mean
and disagreeable. They connect them both with the meanness of
the station to which these qualities commonly belong, and with
many great vices which they suppose usually accompany them;
such as an abject, cowardly, ill-natured, lying, pilfering disposition.'"*
" In general," says Condillac, " the impression we experience in the
ditt"eren^''cn'cumstances of life, makes "s asso-
Condiiiac quoted on- cJate ideas with a force which renders' them
tlie influence of Asso- ' ^ c • t i i i tt- />
ever alter for us indissoluble. \V e cannot, for
example, frequent the society of our fellow-men
without insensibly associating the notions of c.ertain intellectual or
moral qualities with certain corporeal characters. This is the reason
why persons of a decided pliysiognomy please or displease us more
than otiiers ; for a physiognomy is only an assemblage of charac-
tere, with which W'e have associated notions which are not sug-
gested without an accompaniment of satisfaction or disgust. It is
not, therefore, to be marvelled at that we judge men according to
their physiognomy, and that we sometimes feel towards thein at
first sight aversion or inclination. In consequence of these associa-
tions, we are often vehemently prepossessed in favor of certain indi-
viduals, and no less violently disposed against others. It is because
all that strikes us in our friends or in our enemies is associated with
the agreeable or the disagreeable feeling which we severally experi-
ence; and because the faults of the former borrow always something
pleasing from their amiable qualities ; whereas the amiable qualities
of the latter seem always to participate of their vices. Hence it is
that these associations exert a powerful influence on our whole con-
duct. They foster our love or hatred ; enhance our esteem or con-
tempt ; excite our gratitude or indignation ; and produce those
sympathies, — those antipathies, or those capricious inclinations,
for which we are sometimes sorely puzzled to render a reason.
Pescartes tells us that through life he had always found a strong
predilection for squint eyes, — which he explains by the circum«
stance, that the nursery-maid by whom he had been kindly tended^
and to whom as a child he was, consequently, much attached, had
this defect."^ 'S.Gravesande, I think it is, who tells us he knew a
man, and a man otherwise of sense, who had a severe fall from a
1 Elements, vol. i. c. v, § 3. Collected Works, 2 Origine Ues Connoissances HumaiTUS, sect
vol. ii. p. 335. ii. ch. ix. i 80. —Ed.
424 LOGIC. Lect. XXX
wagon ; and thereafter he could never enter a wagon without
fear and trembling, though he daily used, without apprehension,
another and far more dangerous vehicle.^ A girl once and again
sees her mother or maid fainting and vociferating at the appearance
of a mouse ; if she has afterwards to escape from danger, she will
rather pass through flames than take a patent way, if obstructed by
a ridicidus mus. A remarkable example of the false judgments
arising from this principle of association, is recorded by Herodotus
and Justin, in reference to the war of the Scythians with their
slaves. The slaves, after they had repeatedly repulsed several
attacks with arms, were incontinently put to flight when their mas-
ters came out against them with their whips.*
I shall now offer an observation in regard to the appropriate
remedy for this evil influence of Association.
The only mean by which we can* become aware of, counteract,
and overcome, this besetting weakness of our
Only remedy for th« nature, is Philosophy, — the Philosophy of the
influence of Associa- tt ■»!•• j j ^i • ^ j- i l ,.l • ^i.
. , ,„ ., , Human Mind ; and this studied both m the
tiou IS the I liilosopliy ^ '
of theHutnun Mind. cousciousncss of the individual, and in the his-
tory of the species. The philosophy of mind,
as studied in the consciousness of the individual, exhibits to us the
source and nature of the illusion. It accustoms us to discriminate
the casual, from the necessary, combinations of thought ; it sharp-
ens and corroborates our faculties, encourages our reason to revolt
against the blind jncformations of opinion, and finally enables us to
break through the enchanted circle within which Custom and Asso-
ciation had enclosed us. But in the accomplishment of this end,
we are greatly aided by the study of man under the various circum-
stances which have concurred in modifying his intellectual and
moral character. In the great spectacle of history, we behold in
different ages and countries the predominance of different systems
of association, and these ages and countries are, consequently,
distinguished by the prevalence of different systems of opinions.
But all is not fluctuating; and, amid the ceaseless changes of acci-
dental circumstances and precarious beliefs, we behold some princi-
ples ever active, and some truths always commanding a recognition.
We thus obtain the means of discriminating, in so far as our unas-
sisted reason is conversant about mere worldly concerns, between
what is of universal and necessary certainty, and what is only of
» Inirnrtihtio art Philnsophiam. Los'rn. c. 26. which follow are also from >S (iravesande. —
Tile example, bowever. is piven as a t^tipiK^cd Ei>.
cRre, and not as a fuct. Tlte two iuatauces > Herod , iv. 8. JusUu., ii. 6. — B»>
Lkct. XXX. LOGIC. 425
local and temporary acceptation ; and, in reference to the latter, in
witnessing the influence of an arbitrary association in imposing the
most irrational opinions on our fellow-men, our eyes are opened,
and we are warned of the danger from the same illusion to our-
selves. And as the philosophy of man affords us at once the indi-
cation and the remedy of this illusion, so the philosophy of man
does this exclusively and alone. Our irrational associations, our
habits of groundless credulity and of arbitrary skepticism, Snd no
medicine in the study of aught beyond the domain of mind itself
As Goethe has well observed, "Mathematics rem.ove no preju-
dice; they cannot mitigate obstinacy, or temper party-spirit;"^ in a
word, as to any moral influence upon the mind, they are absolutely
null. Hence we may well explain the aversion of Socrates for
these studies, if carried beyond a very limited extent.
The next faculty in order is the Representative, or Imagination
proper, which consists in the greater or less
The Representative power of holding up an ideal object in the
Faculty, or Imagina- r i* ^ • rpi r r>
tiou Proper light 01 consciousuess. I he energy or Kepre-
sentation, though dependent on Retention and
Reproduction, is not to be identified with these operations. For
though these three functions (I mean Retention, Reproduction, and
Representation) immediately suppose, and are immediately depend-
ent on, each other, they are still manifestly discriminated as differ-
ent qualities of mind, inasmuch as they stand to each other in no
determinate proportion. We find, for example, in some individuals
the capacity of Retention strong, but the Reproductive and Repre-
sentative Faculties sluggish and weak. In others, again, the Con-
servative tenacity is feeble, but the Reproductive and Representa-
tive energies prompt and vivid ; while in others the power of
Reproduction may be vigorous, but what is recalled is never pic-
tured in a clear and distinct consciousness. It will be generally,
indeed, admitted, that a strong retentive memory does not infer a
prompt recollection ; and still more, that a strong memory and a
prompt recollection do not infer a vivid imagination. These, there-
fore, though variously confounded by philosophers, we are war-
ranted, I think, in viewing as elementary qualities of mind, which
ought to be theoretically distinguished. Limiting, therefore, the
term Imagination to the mere Faculty of Representing in a more
or less vivacious manner an ideal object, — this Faculty is the
source of errors which I shall comprise in the following paragraph.
1 Wtrke, xxii. p. 258. Quoted by Scheidler, Psychologic, p. 146.
54
426 LOGIC. Lect. XXX.
T CII. Imagination, or the Faculty of Representing with
more or less vivacity a recalled object of
Par.cii.4.imaeina. cognition, is the sourcB of Errors, both
tion, — as a source of ...
Error. whcn it IS too languid and when it is
too vigorous. In the former case, the ob-
ject is represented obscurely and indistinctly ; in the latter,
the ideal representation affords the illusive appearance of a
sensible presentation.
A strong imagination, that is, the power of holding up any ideal
object to the mind in clear and steady colors, is
Explication. g, faculty necessary to the poet and to the artist ;
ecessj y o mag - ^^^^ ^^^ ^^ them alone. It is almost equally
nation m scieutifio _ _ ^ J
pursuits. requisite for the successful cultivation of every
scientific pureuit; and, though differently .ij)-
plied, and different in the character of its representation, it may
well be doubted whether Anstotle did not possess as powerful an
imagination as Homer. The vigor and perfection of this faculty is
seen, not so much in the representation of individual objects and
fiJigmentary sciences, as in the representation of systems. In the
better ages of antiquity the perfection, the beauty, of all works
of taste, whether in Poetry, Eloquence, Sculp-
Diveree characteris- . !->•.• -nr • • • n
. . , . ture, Painting, or Music, was pi-incipally esti-
tics of Art in ancient ' ® ^ r r j
and modirn times. mated from the Symmetry or proportion of all
the parts to each other, and to the whole which
they together constituted ; and it was only in subservience to this
general harmony that the beauty of the several parts was appreci-
ated. In the criticism of modern times, on the contrary, the reveree
is true ; and we are disposed to look more to the obtrusive qualities
of details, than to the keeping and unison of a whole. Our works
of art are, in general, like kinds of assorted patch-work ; — not sys-
tems of parts all subdued in conformity to one ideal totality, but
coordinations of independ-ent fragments, among which a '■'■ 2:>urpureu8
pannus''^ seldom comes amiss. The reason of this difference in
taste seems to be, what at first sight may seem the reverse, that in
antiquity not the Reason but the Imagination was the more vigor-
ous;— that the Imagination was able to represent simultaneously a
more comprehensive system; and thus the several parts being re-
garded and valued only as conducive to the general result, — these
])arts never obtained that individual importance, which would have
fallen to them had they been only created and only considered for
themselves. Now this power of representing to the mind a com-
plex system in all its bearings, is not less requisite to the philosopher.
Lkct. XXX. LOGIC. 427
than to the poet, though the representation be different in kind ;
and the nature of the philosophic representations, as not concrete
and palpable like the poetical, supposes a more arduous operation,
and, therefore, even a more vigorous faculty. But Imagination, in
the one case and in the other, requires in proportion to its own
power a powerful intellect ; for imagination is not poetry nor
philosophy, but only the condition of the one and of the other.
But to speak now of the Errors which arise from the dispropor-
tion between the Imagination and the Judg-
Errors which arise ment ; — they originate either in the weakness,
from the dispropor- ... ,. "" i ,. i r'
.i„„Kot„o^„T™o i „ or m the mordinate strength, ot the lormor.
t ion between Imagma- » '
tion and Judgment. In regard to the errors which arise from the
Those arising from imbecility of the Representative Faculty, it is
the weakness of Imagi- . t/v. i. . • i ^i," • -l 'Tx
" not dimcult to conceive how this imbecility
nation. _ •'
may become a cause of erroneous judgment.
The Elaborative Faculty, in order to judge, requires an object, —
requires certain diiferences to be given. Now, if the imagination
be weak and languid, the objects represented by it will be given in
such confusion and obscurity, that their differences are either null
or evanescent, and judgment thus rendered either impossible, or
possible only with the jji-obability of error. In these circumstances,
to secure itself from failure, the intellect must not attempt to rise
above the actual presentations of sense ; it must not attempt any
ideal analysis or synthesis, — it must abandon all free and self-
active elaboration, and all hope of a successful cultivation of
knowledge.
Again, in regard to the opposite errors, those arising from the
disproportioned vivacity of imagination, — these
From/ its dispropor- ^^.^ equally apparent. In this case the renewed
tionate vivacity. i •' i i
or newly-modified representations make an equal
impression on the mind as the original presentations, and are, con-
sequently, liable to be mistaken for these. Even during the percep-
tion of real objects, a too lively imagination mingles itself with the
observation, which it thus corrupts and falsities. Thus arises what
is logically called the vitium subreptionis} This is frequently seen
in those pretended observations made by theorists in support of
their hypotheses, in which, if even the possibility be left for imagi-
nation to interfere, imagination is sure to fill up all that the senses
may leave vacant. In this case the observers are at once dupes and
deceivers, in the words of Tacitus, '■'■ Fingxmt simul creduntque^^
1 Krug, Logik,^ 142. Anm. — Ed.
3 Hist. lib. ii c. 8. See Lectures on Metaphysics, p. 64. — Ed.
428 LOGIC. LiccT. XXX.
In regard to the remedies for these defects of the Representative
Faculty ; — in tlie former case, the only allevia-
ICeroedies for these ^j^,^ ^j^.^^ ^^^ ^^ proposed for a feeble Imagina-
(k'Cccts of the I magi- . . . • i i i • i
„^^■^Q^ tion, IS to animate it by the contemplation and
study of those works of art which are the jiro-
ducts of a strong Phantasy, nnd which tend to awaken in the stu-
dent a corresponding energy of that fiiculty. On the other hand, u
too powerful imaginntion is to be quelled and regulated by abstract
thinking, and the »tudy of philosophical, perhaps of mathematical,
science.^
The faculty wliich next follows, is the Elaborative Faculty, Com-
parison, or the Faculty of Relations. This is the Understanding,
in its three functions of Conception, Judgment, and Reasoning.
On this faculty take the following paragraph.
^ cm. The Affections and the Lower Cognitive Faculties
afford the sources and occasions of error;
par.ciii.oEiabora- fcut [^ jg i\^q Ehiborativc Faculty, Under*
tive Faculty, — as a t /-^ • t i i • i
source of Error. Standing, Comparison, or Judgment, which
truly errs. This faculty does not, however,
eiT from strength or over-activity, but from inaction ; ami this
inaction arises either from natural weakness, from want of
exercise, or from the impotence of attention.^
I formerly olwerved that error does not lie in the conditions
of our higher faculties themselves, and that
Kxpiication. ^j^^.^^. faculties are not, by their own laws, deter-
Error does not lie in • i /> i • -i i •
the conditions of our "ii"^'*! ^o fulsc judgments or conclusions:
Higher Faculties, but
in po^f^ible iu tlie ap. " Nam neque dccfpitur ratio, noc decipit unquam.''^
plication of the laws
of tlioFc faculties to _,. , . , . „ , , , i i i
determinate c.*e«. ^^ ^^^^ ^^*^''^ Otherwise, all knowledge would be
impossible, — the root of our nature would be a
lie. "But in the application of the laws of our higher faculties to
determinate cases, many errore are possible ; and these errors may
actually be occasioned by a variety of circumstances. Thus, it is a
law of our intelligence, that no event, no phenomenon, can be
thought as absolutely beginning to be ; we cannot but think
'Jiat all its constituent elements had a virtual existence prior
X) th«ir concurrence, to necessitate its manifestation to us; w«
1 Cr. Krnr;, Logik,i lb6. Anm. — Ed.
i Kra-, Logils, { 148. — Ed. [Cf Fries, Logik, 1 108. B«chm»nn, Ligik, } 411.]
^ Sec above, p. 889 — Ed.
Lkct. XXX.
LOGIC.
429
are thus unable to accord to it more than a relative commencement,
in other words, we are constrained to look upon it as the effect ol"
antecedent causes. Now though the law itself of our intelligence
— that a cause there is for every event — be altogether exempt
from error, yet in the application of this law to individual cases,
that is, in the attribution of determinate causes to determinate
effects, we are easily liable to go wrong. For we do not know,
except from experience and induction, what particular antecedents
are the causes of particular consequents ; and if our knowledge of
this relation be imperfectly generalized, or if we extend it by a
false analogy to cases not included within our observation, error is
the inevitable consequence. But in all this there is no fault, no
failure, of intelligence, there is only a deficiency, — a deficiency in
the activity of intelligence, while the Will determines us to a de-
cision before the Understanding has become fully conscious of cer-
tainty. The defective action of the Under-
standing may arise from three causes. In the
first place, the faculty of Judgment may by
nature be too feeble. This is the case in idiota
and weak persons. In the second place, though
not by nature incompetent to judge, the intel-
lect may be without the necessary experience,
— may not possess the grounds on which a cor-
rect judgment must be founded. In the third place, — and this is
the most frequent cause of error, — the failure of the understanding
is from the incompetency of that act of will which is called Atten-
tion. Attention is the voluntary direction of the mind upon an
object, with the intention of fully apprehending it. The cognitive
(energy is thus, as it were, concentrated upon a single point. We,
therefore, say that the mind collects itself, when it begins to be
attentive ; on the contrary, that it is distracted, when its attention
is not turned upon an object as it ought to be. This fixing — this
concentration, of the mind upon an object can only be carried to a
wrtain degree, and continued for a certain time. This degree and
.his continuance are both dependent upon bodily circumstances; and
they are also frequently interrupted or suspended by the intrusion
of certain collateral objects, which are forced upon the mind, either
from without, by a strong and sudden impression upon the senses, or
from within, through the influence of Association ; and these, when
once obtruded, gradually or at once divert the attention from the
|)4'iginal and principal object. If we are not sufficiently attentive,
r if the effort which accompanies the concentration of the mind
upon a single object be irksome, there arises hurry and thoughtless-
Defective action of
-tbe Understanding
I may arise from three
I Muses.
(a) Natural feeble-
ness, (b) Want of ne-
cessary experience, (c)
[Incompetency of at-
ation.
480
LOGIC.
Lect. XXX
ness in judging, inasmuch as we judge either before we have fully
Bought out the grounds on which our decision ought to proceed, or
have competently examined their validity and effect. It is hence
manifest that a multitude of erroi-s is the inevitable consequence." '
In regard to the Regulative Faculty, — Common Sense, — Intel-
ligence,— vovs, — this is not in itself a source
6. Regulative Fac- ^f error. Errors may, however, arise either
ulty,— not properly a „ i i • 4.1 i • •
eource of Error. iroxYi overlooking the laws or necessary princi-
ples which it does contain ; or by attributing to
it, as necessary and original data, what are only contingent general-
izations from experience, and, consequently, make no part of its
complement of native truths. But these errors, it is evident, are
not to be attributed to the Regulating Faculty itself, which is only
a place or source of principles, but to the imperfect operations of
the Understanding and Self-consciousness, in not properly observ-
ing and sifting the phenomena which it reveals.
Besides these sources of Error, which immediately originate in
the several powers and faculties of mind, there
are othere of a remoter origin arising from the
different habits which are determined by the
differences of sex,^ of age,' of bodily constitu-
tion,* of education, of rank, of fortune, of pro-
fession, of intellectual pursuit. Of these, how-
ever, it is impossible at present to attempt an analysis ; and I shall
only endeavor to afford you a few specimens, and to refer you
for information in regard to the others to the best sources.
Intellectual pursuits or fivorite studies, inasmuch as these deter-
mine the mind to a one-sided cultivation, that
is, to the neglect of some, and to the dispropor-
tioned development of other, of its faculties, are
among the most remarkable causes of error.
This partial or one-sided cultivation is exempli-
fied in three different phases. The first of
these is shown in the exclusive cultivation of
the powers of Observation, to the neglect of
the higher faculties of the Understanding. Of
this type are your men of physical science. In this department of
knowledge there is chiefly demanded a patient habit of attention to
details, in order to detect phenomena, and, these discovered, their
Remote sources of
Error in the different
habits determinated
by sex, age, bodily
constitution, educa-
tion, etc.
Selected examples
of these.
A one-sided cultiva-
tion of the intellectual
lowers.
This exemplified in
three difTercnt phases.
Exclusive cultivation.
1. Of the powers of
Observation.
1 Krug, Logilc, i 148. Anm. In some places
iliglvtly changed. — Ed.
2 [See Stewart, Elements, vol. iii. part iii.
s«ct. V. chap. i. Works, vol. ir. p. 238 et stq. ]
3 [Aristotle, Rhtt., L. il. c. 12. Crousaz.
Logique, t. i. part i. sect. i. ch. v. f 15, p. 104.]
4 [See Crousax, Logique, t. i. p. i. sect. i. cb.
v. p. 91 et ftq.]
Lect. XXX. LOGIC. 431
generalization is usually so easy that there is little exercise afforded
to the higher energies of Judgment and Reasoning. It was Bacon's
boast, that Induction, as applied to nature, would equalize all tal-
ents, level the aristocracy of genius, accomplish marvels by coopera-
tion and method, and leave little to be done by the force of individ-
ual intellects. This boast has been fulfilled. Science has, by the
Inductive Process, been brought down to minds, who previously
would have been incompetent for its cultivation, and physical knowl-
edge now usefully occupies many who would otherwise have been
without any rational pursuit. But the exclusive devotion to such
studies, if not combined with higher and graver speculations, tends
to wean the student from the more vigorous efforts of mind,
which, though unamusing and even irksome at the commencement,
tend, however, to invigorate his nobler powers, and to prepare him
for the final fruition of the highest happiness of his intellectual
nature.
A partial cultivation of the intellect, opposite to this, is given
in the exclusive cultivation of Metaphysics and
2. Of Metaphysics. ^f Mathematics. On this subject I may refer
3. Of Mathematics. ^ , ^. ^-m-o^ j. •
Stewart referred to. y^^^ ^° ^'^^^ obscrvations of Mr. Stcwart, m
two chapters entitled The 3fetaphysician and
The Mathematician, in the third volume of his Elements of the
Philosophy of the Human Mind, — chapters distinguished equally
by their candor and their depth of observation. On this subject
Mr. Stewart's authority is of the highest, inasmuch as he was dis-
tinguished in both the departments of knowledge, the tendency of
which he so well develops.
LECTURE XXXI.
MODIFIED STOICHEIOLOG Y.
SECtlON II. — ERROR— ITS CAUSES AND REMEDIED.
C — LANGUAGE. — D. — OBJECTS OF KNOWLEDGE.
In my last Lecture, I concluded the survey of the En-oi*s which
have their origin in tlie conditions and circnm-
. -.aiiguusre, — lu g^anccs of the several Cosinitive Faculties, and
!i souic'i; ot Error. *-^ '
now proceed to that source of false judgment
wliich lies in the imperfection of the Instrument of thought and
Coininnnicntion, — I mean Language.
Much controversy has arisen in regard to the question, — Has
man invented Language? But ihe differences
Has man Invented ^,f opinion have in a great measure arisen from
itv..f the question. ^'^^. ambiguity or complexity of the terms, m
which the problem has been stated. By lan-
f/n«/r/e we may mean cither the power which man possesses of asso-
ciating his thought with signs, or the particular systems of signs
with which different portions of mankind have actually so associ-
ated their thoughts.
Taking language in the former sense, it is a natural faculty, an
original tendency of mind, and, in this view,
In what sense Lan- ^^^ -^^^ ^^ more invented language than he
liuagc is natural to , . i i i x /» i p
^g^ has invented thouglit. \w fact, the power oi
thought and the power of language are equally
entitled to be considered as elementary qualities of intelligence;
foi- while they are so different that they cannot be identified, they
are still so reciprocally necessary that the one cannot exist .without
the other. It is true, indeed, that presentations and representations -
of given individual objects might have taken place, although there
were no signs with which they were mentally connected, and by
which they could be overtly expressed ; but all complex and facti-
tious constructions out of these given individual objects, in other
Lkct. XXXI.
LOGIC
483
words, nil notions, concepts, goner.il idcns, or thoughts proper,
would have been impossible without an association to certain signs,
by which their scattered elements might be combined in unity,
and their vague and evanescent existence obtain a kind of definite
and fixed and palpable reality. Speech and cogitation are thus the
relative conditions of each other's activity, and both concur to the
accomplishment of the same joint result. The Faculty of Think-
ing— the Faculty of forming General Notions — being given, this
necessarily tends to energy, but the energy of thinking depends
upon the coactivity of the Faculty of Speech, which itself tends
equally to energy. These faculties, — these tendencies, — these
energies, th-us coexist and have always coexisted ; and the result of
their combined action is thought in language, and language in
thought. So much for the origin of Language, considered in gen-
eral as a faculty.
But, though the Faculty of Speech be natural and necessary,
that its manifestations are, to a certain extent,
contingent and artificial, is evident from the
simple fact, that there are more than a single
language actually spoken. It may, therefore,
be asked, — Was the first language, actually
spoken, the invention of man, or an inspiration,
of the Deity ? The latter hypothesis cuts, but
does not loose the knot. It declares that ordi-
ary causes and the laws of nature are insufiicient to explain the
henomenon, but it does not prove this insufficiency ; it thus vio-
tes the rule of Parcimony, by postulating a second and hypothet-
cause to explain an effect, which it is not shown cannot be
ccounted for without this violent assumption. The first and
eatest difficulty in the question is thus : — It is necessary to think ,
in order to invent a language, and the invention
of a language is necessary in order to think;
for we cannot think without notions, and no--
lions are only fixed by words.^ This can only be solved, as I have
aid, by the natural attraction between thought and speech, — by
iheir secret afl^nity, which is such that they suggest and, pari
<assv, accompany each other. And in regard to the question, —
hy, if speech be a natural faculty, it does not manifest itself like
ther natural principles in a uniform manner, — it may be answered
Was the first lan-
guage, actually spo-
ken, the invention of
man, or an inspiratioa
of the Deity r
The latter hypothe-
I considered.
Difficulty of the
uestion.
1 See Rousseau, Discours svr V Origine de P pour apprendre Si penser, ils ont en bien plus
)K^aliti partni Us Hommes. Premiere Tartie. besoin encore de savoir penser pour trouver
PSi le$ hommes ont eu besoin de la parole )-art de la parole."— Ed.
55
484 LOGIC. Lect. XXXT.
that the Faculty of Speech is controlled and modified in its exer-
cise by external circumstances, in consequence of which, though its
exertion be natural and necessai-y, and, therefore, identical in all
men, the special forms of its exertion are in a great degree conven-
tional and contingent, and, therefore, different among different por-
tions of mankind.
Considered on one side, languages are the results of our intelli-
gence and its immutable laws. In consequence
Language has a gen- ^f ^.j^jg^ ^^ley exhibit in their progress and devel-
eral and a special , , , ,
character opment resemblances and common characters
which allow us to com pure and to recall them
to certain primitive and essential forms, — to evolve a system of
Universal Grammar. Considered on another side, each language ia
the olF-<pring of particular wants, of special circumstances, physical
and moral, and of chance. Hence it is that every language has
particular forms as it has peculiar words. Language thus bears
the impress of human intelligence only in its general outlines.
There is, therefore, to be found reason and philosophy in all lan-
guages, but we should be wrong in believing that reason and phi-
losophy have, in any language, determined everything. No tongue,
how pei-fect soever it may appear, is a corn-
No language is a pj^^g ^nd perfect instrument of human thought.
perfect instrument of -,, . •,. . ,
thoucht J^rom its vei'y conditions every language must
be imperfect. The human memory can only
compass a limited complement of words, but the data of sense, and
still more the combinations of the undei-standing, are wholly un-
limited in numbei-. No language can, therefore, be adequate to
the ends for which it exists; all are imperfect, but some are far less
incompetent instruments than othei*s.
From what has now been said, you will be prepared to find in
Language one of the principal sources of Error; but before I go on
to consider the particular modes in Avhich the Imperfections of
Language are the causes of false judgments, — I shall comprise the
general doctrine in the following paragraph.
% CIV. As the human mind necessarily requires the aid
of signs to elaborate, to fix, and to commu-
par. CIV. Language, nicatc its uotious, and as Articulate Sounds
— as a source of Error. '
are the species of signs which most effect-
ually afford this aid. Speech is, therefore, an indispensable
instrument in the higher functions of thought and knowledge.
But as speech is a necessary, but not a j^erfect, instrument, its
imperfection must react upon the mind. For the Multitude
Lkct. XXXI. LOGIC. 486
of Languages, the Difficulty of their Acquisition, their neces-
sary Inadequacy, and the consequent Ambiguity of Words,
both singly and in combination, — these are all copious sources
of Illusion and Error.^
We have already sufficiently considered the reason why thought
is dependent upon some system of sign.s or sym-
Expiication. )3Q|g both for its internal perfection and external
Signs necefsary for • 9 mi i i ^1 ^1
the internal operation expression.- The analyses and syntheses, - the
of Thought. decompositions and compositions, — in a word,
the elaborations, performed by the Understand-
ing upon the objects presented by External Perception and Self-
Consciousness, and represented by Imagination, — these operations
are faint and fugitive, and would have no existence, even for the
conscious mind, beyond the moment of present consciousness, were
we not able to connect, to ratify, and to fix them, by giving to
their parts (which would otherwise immediately fall asunder) a
permanent unity, by associating them with a sensible symbol, which
we may always recall at pleasure, and which, when recalled, recalls
along with it the characters which concur in constituting a notion
or factitious object of intelligence. So far signs are necessary for
the internal operation of thought itself But for the communica-
tion of thought from one mind to another, signs arc equally indis-
pensable. For in itself thought is known, — thought is knowable,
only to the thinking mind itself; and were we
And for the commu- , ui i i ^ * • 1 i _«"
not enabled to connect certain complements of
iiiciitiun of 1 liought. . . *
thought to certain sensible symbols, and by
their means to suggest in other minds those complements of
thought of which we were conscious in ourselves, we should never
be able to communicate to others what engaged our interest, and
man would remain for man, if an intelligence at all, a mere isolated
intelligence.
In regard to the question, — What may these sensible symbols
be, by which we are to compass such memorable effects, — it is
needless to show that mien and gesture, which, to a certain extent,
afford a kind of natural expression, are altogether inadequate to the
double purpose of thought and communication, which it is here
required to accomplish. This double purpose can be effected onl^
1 Krug, Lo^j'i:, § 145. — Ed. [Cf. Ernesti, Logi'Jfc, J 109. Care, Lo^ig«c, Part. i. ch. i. art.
Inkia DnctrincB Solirlioris: Pars Alttra; Dialec- 9, p. 121. Crousaz, Toussaint.] [Crousaz, Lo-
tica, c. 2, i 24. Wyttenbach, Pra-cepta Phil, giguf, t. iii. part i. tect. iil. c. 2, p. 63 et setf
Log. P. iii. c. iii. p. 98. Tittcl, Logik, p. 292. Toussaint, De la Ptnsie. Chs. viii. x. — Ed.}
Eirwan, Logick, i. 214. Fries, System tier a See above, p. 430. — Err.
486
LOGIC.
Lect. XXXL
Intonations of the
voice tlie only ade-
quate sensible symbols
of thouj;ht and its
communication.
Tliese inarticulate
and articulate.
The latter constitute
Language Proper.
How Language is a
(Ource of Error.
by symbols, which express, through intonations of the Aoiee, what
is passing in the mind. The.se vocal intonations
are either inarticulate or articulate. The for-
mer are mere sounds or cries ; and, as Buch, an
expression of the feelings of which the lower
animals are also capable. The latter ( onstitute
words, and these, .is the expression of thoughts
or notions, constitute Language Proper or
Speech,^ Speech, as we have said, as the in-
strument of elaborating, fixing, and commu-
nicating our thoughts, is a principal mean of
knowledge, and even the indispensable condition on which depen<is
the exercise of our higher cognitive faculties. But, at the same time,
in consequence of this very dependence of thought upon language,
inasmuch as language is itself not perfect, the underatanding is not
only restrained in its operations, and its higher development, conse-
quently, checked, but many occasions are given of positive error.
For, to say nothing of the impediment presented to the free com-
munication of thought by the multitude of tongues into which
human language is divided, in consequence of which all speech
beyond their mother-tongue is incomprehensible to those who do
not make a study of other languages, — even the accurate learning
of a single language is attended with such difficulties, that perhaj>8
there never yet has been found an individual who was thoroughly
acquainted with all the words and modes of verbal combination in
any single language, — his mother-tongue even not excepted. But
the circumstance of principal importance is,
that how copious and expressive soever it may
be, no language is competent adequately to
denote all possible notions, and all possible rela-
tions of notions, and from this necessary jioverty
of language in all its different degrees, a certain inevitable ambigu-
ity arises, both in the employment of single words and of words in
mutual connection.
As this is the ])rincipai source of the error originating in Lan-
guage, it will be proper to be a little more
explicit. And here it is expedient to take into
accoimt two circumstances, which mutually af-
fect each other. Tlie first is, that as the vocab-
ulary of every language is necessarily finite, it
is necessarily disproportioned to the multiplicity, not to say infinity,
of thought ; and the second, that the complement of words in any,
The ambiguity of
words the principal
source of error origi-
nating in Language.
Two circumstances
%Mtiderthi8 bead, which
mutually affect each
other.
1 Cf. Krug, Logik, i 146. Anm. — Eo.
»
r«KCT. XXXL LOGIC. 43T
given language has been always filled up with terms significant of
objects and relations of the external world, before the want was
experienced of words to express the objects and relations of the
internal.
From the first of these circumstances, considered exclusively
and by itself, it is manifest that one of two
The vocabulary of alternatives must take place. Either the word*
every latiKuatre ncces- ^ i , n • , . ,
., « „ r^ of a language must each designate only a smgle
rarily finite. Conse- . Jo
qnencee of this. notion, — a single fasciculus of thought, — the
multitude of notions not designated being al-
lowed to perish, never obtaining more than a momentary exist-
ence in the mind of the individual ; or the words of a language
must each be employed to denote a plurality of concepts. In
the former case, a small amount of thought would be expressed,
but that precisely and without ambiguity; in the latter, a large
amount of thought Avould be expressed, but that vaguely and
equivocally. Of these alternatives (each of which has thus its
advantages and 'disadvantages), the latter is the one which has
universally been preferred ; and, accordingly, all languages by the
same word express a multitude of thoughts, more or less differing
from each other. Nov.', what is the consequence of this? It i«
plain that if a word has more than a single meaning attached
to it, when it is employed it cannot of itself directly and per-
emptorily suggest any definite thought; — all that it can do is
vaguely and hypothetically to suggest a variety of different no-
tions ; and we are obliged from a consideration of the context,
— of the tenor, — of the general analogy, of the discourse, to sur-
mise, wifh greater or less assurance, with greater or less precision,
what p;uticular bundle of characters it was intended to convey.
Words, in fact, as languages are constituted,
Words are mcrclv i j.t • ^i, j. ii •
, ■ do nothing more than suggest, — are nothing
liintK to the nund * trJ5 i »
more than hints ; hints, likewise, which leave
the principal part of the process of interpretation to be performed
by the mind of the hearer. In this respect, the effect of words
resembles the effect of an outline or shade of a countenance
with which we are familiar. In both cases, the mind is stimulated
to fill up what is only hinted or pointed at. Thus it is that the
function' of language is not so much to infuse knowledge from
one intelligence to another, as to bring two minds into the same
train of thinking, and to confine them to the same track. In this
procedure what is chiefly wonderful, is the rapidity with which the
mind compares the word with its correlations, and in general, with-
out the slightest effort, decides which among its various meanings
438 LOGIC. . Li^ci. XXXL
is the one which it is here intended to convey. But liow marvel--
lous soever be the ease and velocity of this process of selection, it
cannot always be performed with equal certainty. Words are often
employed with a plurality of meanings ; several of which may
quadrate, or be supposed to quadrate, with the general tenor
of the discourse. Error is thus possible ; and it is also proba-
ble, if we have any prepossession in fixvor of one interpreta-
tion rather than of another. So copious a source of error is
the ambiguity of language, that a very large jDroportion of human
controversy has been concerning the sense in which ceilain terms
should be understood; and many disputes have even been fiercely
waged, in consequence of the disputants being unaware that
they agreed in opinion, and only differed in tlie meaning they
attached to the words in which that opinion was expressed.
On this subject I may refer you to the very amusing and very
instructive treatise of Werenfelsias, entitled De LogomacMis
Eruditorum.
"In regard to a remedy for this description of error, — this lies
exclusively in a thorough study of the language
Remedy for error employed in the communication of knowledge,
arising from Lan- , . . • > i » »> /-i • •
g and m an acquaintance with the rules ot Criti-
cism and Interpretation. The stuuy of lan-
guages, when rationally pursued, is not so unimportant as'manjr
fondly conceive ; for misconceptions most frequently ai"ise solely
from an ignorance of words ; and eveiy language may, in a cer-
tain sort, be viewed as a commentary upon Logic, inasmuch as
every language, in like manner, mirrors in itself the laws of
thought.
"In reference to the rules of Criticism and Interpretation, —
these especially should be familiar to those who make a study
of the writings of ancient authors, as these writings have de-
scended to us often in a very mutilated state, and are composed
in languages which are now dead. How many theological errors,
for example, have only arisen because the divines were either
ignorant of the principles of Criticism and Hermeneutic, or
did not properly apply them! Doctrines originating in a cor*
rupted lection, or in a figurative expression, have thus arisen-j
and been keenly defended. Such errora are best combated bj
philological weapons ; for these pull them up along with their
roots.
" A thorough knowledge of languages in general accustoms th«
mind not to remain satisfied with the husk, but to penetrate io,^
oven to the kernel. With this knowledge we shall not so easiljri
Lect. XXXI. LOGIC. 439
imagine 'that we understand a system, when we only possess
the language in which it is expressed ; we sliall not conceive
that we truly reason, when we only employ certain empty words
and formulae ; we shall not betray oui-selves into unusual and
obscure expressions, under which our meaning may be easily mis-
taken ; finally, we shall not dispute with others about words, when
we are in fact at one with them in regard to things." ^ So much
for the errors which originate in Language.
As to the last source of Error which I enumerated, — the
Objects themselves of our knowledge, — it is
IV. Source of Error, hardly necessary to say anything. It is evident
— the Objects of our ^i ^ ^^ i i i ,
.. , , that some matters are obscure and abstruse.
Knowledge. '.
while others are clear and palpable ; and that»
consequently, the probability of error is greater in some studies
than it is in others. But as it is impossible to deliver any special
rules for these cases, different from those which are given for the
Acquisition of Knowledge in general, concerning which we are
soon to speak, — this source of error may be, therefore, passed over
in silence.
We have now thus finished the consideration of the various
Sources of Error, and —
% CV. The following rules may be given, as the results
of the foregoing discussion, touching the
Par. CV. Kules & O ' &
touching the Causes Causcs and Remedies of our False Judg-
and Semedies of our mentS
False Judgments. __,
1°. Endeavor as far as possible to obtain
a clear and thorough insight into the laws of the Understand-
ing, and of the Mental Faculties in general. Study Logic and
Psychology.
2°. Assiduously exercise your mind in the application of
these laws. Learn to think methodically.
3°. Concentrate your attention in the act of Thinking ;
and principally employ the seasons when the Intellect is
alert, the Passions slumbering, and no external causes of
distraction at work.
4°. Carefully eliminate all foreign interests from the objects
of your inquiry, and allow yourselves to be actuated by the
interest of Truth alone.
5". Contrast your various convictions, your past and present
judgments, with each other ; and admit no conclusion as cer-
iKrug, Logik, i 157. Anm. — Ed.
440
LOGIC.
Lrct. XXXI
tain, until it has been once and again thoroughly e^famined,
and its correctness ascertained.
6°. Collate your own persuasions with those of others;
attentively listen to and weigh, without prepossession, the
judgments formed by others of the opinions which you your-
selves maintain.^
1 Cf. Krug, Logik, { 16a BacbmaDn, Logik, i 416- —Ed.
LECTURE XXXII.
MODIFIED METHODOLOGY.
Means by which oar
knowledge obtains the
character of Perfec-
tion, viz., the Acquisi-
tion and the Commu-
nication of Knowl-
edge.
SECTION I.— OF THE ACQUISITION OF KNOWLEDGR
I. EXPERIENCE. — A. PERSONAL: — OBSERVATION-
INDUCTION AND ANALOGY.
In our last Lecture, having concluded the Second Department
of Concrete Logic, — that which treats of the
Causes of Error, we now enter upon the Third
part of Concrete or Modified Logic, — that
which considers the Means hy which our
Knowledge obtains the character of Perfec-
tion. These means may, in general, be re-
garded as two, — the Acquisition and the
Communication of knowledge, — and these two means we shall,
accordingly, consider consecutively and apart.
In regard to the Acquisition of Knowledge, — we must consider
this by reference to the different kinds of knowl-
edge of which the human intellect is capable.
And this, viewed in its greatest universality, is
of two species.
Human knowledge, I say, viewed in its greatest universality, is
of two kinds. For either it is one of which the
uman now e ge objects are given as contingent phaenomena, or
one in which the objects are given as necessary
&cts or laws. In the former case, the cognitions are called empir-
ical^ experiential, or of experience; in the latter, puT^, intuitive,
rational, or of reason, also of common sense. These two kinds
of knowledge are, likewise, severally denominated cognitions a
posteriori and cognitions a 2>}'iori. The distinction of these two
species of cognitions consists properly in this, — that the former
are solely derived frotn the Pi-esentations of Sense, External and
Internal ; whereas the ktter, though first manifested on the occasion
56
The acquisition of
Knowledge.
442 LOGIC Lect. XXXIL
of such Presentations, are not, however, mere products of Sense;
on the contrary, they are laws, principles, forms, notions, or by
whatever name they may be called, native and original to the mind,
that is, founded in, or constituting the very nature of. Intelligence ;
:in<l, accordingly, out of the mind itself they must be developed,
.'tnd not sought for and acquired as foreign and accidental acquisi-
tions. As the Presentative Faculties inform us only of what exists
and what happens, that is, only of facts and events, — such empir-
ical knowledge constitutes no necessary and universal judgment;
all, in this case, is contingent and particular, for even our general-
ized knowledge has only a relative and precarious universality.
The cognitions, on the other hand, which are given as Laws of
Mind, are, at once and in .themselves, universal and necessary. We
cannot but think them, if we think at all. The
Doctrine of the Ac- doctnne, therefore, of the Acquisitiou'of Knowl-
fiuisition of Knowl- ■, . ' ^ c j. ^ ^i ii ^ ^ ^
, . . , „ edge, must consist of two parts, — the nrst treat-
edge consists ol two .
parts. iHg of the acquisition of knowledge through the
data of Experience, the second, of the acquisi-
tion of knowledge through the data of Intelligence.^
In regard to the first of these sources, viz.. Experience, — this is
either our own experience or the experience of
I. The Doctrine of others, and in either case it is for lis a mean of
encror'two kinds!*" knowledge. It is manifest that the knowledge
we acquire through our jjersonal experience, is
far superior in degree to that which we obtain through the experi-
ence of other men ; inasmuch as our knowledge of an object, in
the fonner case, is far clearer and more distinct, far more complete
and lively, than in the latter; while at the same time the latter
also affords us a far inferior conviction of the correctness and cer-
tainty of the cognition than the former. On the other band, for-
eign is far superior to our propei experience in this, — that it is
much more comprehensive, and that, without this, man would be
deprived of those branches of knowledge which are to him of the
most indispensable importance. Now, as the principal distinction
of ex))erience is thus into our own experience and into the experi-
ence of others, we must consider it more closely in this twofold
relation.'' First, then, of our Personal Experience.
Experience necessarily supposes, as its primary condition, certain
presentations by the faculties of External or of Internal Perception,
1 See F.sf'er, Lngik, i 145 — Ed. In regard ocquired cither, 1°, By experience; or, 2°, On
to tlic nciiuisition of kno\vlcd;re, — nil knowl- occasion of expericixc.
ccigc may be called acquired, inasmuch as it is 2 Esfcr, Lo^ik, J 146. — 'Ej>,
Lect. XXXII. LOGIC. 443
and is, therefore, of two kinds, according as it is conversant about
the objects of the one of these faculties, or the
1. Personal Expert- objects of the Other. But the presentation of a
ence. '' ^
fact of the external or of the internal M^orld is
not at once an experience. To this there is required a continued
series of such presentations, a comparison of these together, a men-
tal separation of the different, a mental combination of the similar,
and it, therefore, over and above the operation of the Presentative
Faculties, requires the cooperation of the Retentive, the Repro-
ductive, the Representative, and the Elaborative Faculties. In
regard to Experience, as the first means by which we acquire
knowledge through the legitimate use and application of our Cog-
nitive Faculties, I give you the following pai*agraph :
% CVI. The First Mean towards the Acquisition of Knowl-
edge is JExperience {experientia^ ifnreLpia).
Par. CVI. Ezperi- Experience may be, rudely and generally,
ence; what, — in een- . .
erai. described as the apprehension of the phse-
nomena of the outer world, presented by
the Faculty of External Perception, and of the phsenomena of
the inner world, presented by the Faculty of Self-conscious-
ness ; — these phjenomena being retained in Memory, ready for
Reproduction and Representation, being also arranged into
order by the Understanding.
This paragraph, you will remark, affords only a preliminary view
of the general conditions of Experience. In
Explication. ir>i •• • ^ ■, • i
the first place, it is evident, that without the
Presentative, or, as they may with equal propriety be called, the
Acquisitive, Faculties of Perception, External and Internal, no
experience would be possible. But these faculties, though afford-
ing the fundamental condition of knowledge, do not of themselves
make up experience. There is, moreover, required of the phaa-
nomena or appearances the accumulation and retention, the repro-
duction and representation. Memory, Reminiscence, and Imagina-
tion must, therefore, also cooperate. Finally, unless the phajnoraena
be compared together, and be arranged into classes, according to
their similarities and differences, it is evident that no judgments, —
no conclusions, can be formed concerning them ; but without a
judgment knowledge is impossible; and as experience is a knowl-
edge, consequently experience is impossible. The Understanding
or Elaborative Faculty must, therefore, likewise cooperate. Mani-
444 LOGIC. Lkct. XXXIL
ilus has well expressed the nature of experience in the following
lines.
" Per varies usus artem experientia fecit,
Exemplo monstrante viam." l
And Afranius in the others:
"Usus me Rcnuit, mater peperit Memoria;
Sophiam voeant me Graii, vo> Sapientiam."'
" Our own observation, be it external or internal, is either with,
or without, intention ; and it consists either of a
( 'ointnon and Scien- • i»-o **• i au^^-
.„ ^ . series ot Presentations alone, or Abstraction
tine Lxperieuce.
and Reflection supervene, so that the presenta-
tions obtain that completion and system which they do not of
themselves possess. In the former case, the cxpericrrce may be
called an Unlearned or a Common; in the latter, a Learned or
Scientific Experieyice. Intentional and reflective experience is called
Observation. Observation is of two kinds; for
Observation, -what. either the objects which it considers remain
Of two kinds, — Ob- , j ■ ^ . t .• .1
„ . unchan2:ed, or, previous to its application, they
Kcrvutio!) i roper, sua o ' ' 1 ^ 11 i j
Kx|.».-i iincut. •'ii'e made to undergo certain arbitrary changes,
or are placed in certain factitious relations. In
the latter case, the observation contains the specific name of Ex-
periment. Observation and ex[)erimcnt do not, therefore, constitute
opposite or two difierent procedures, — the latter is, in propriety,
only a certain subordinate modification of the former ; for, while
observation may accomplish its end without experiment, experi-
ment without observation is impossible. 'Observation and experi-
ment are manifestly exclusively competent upon the objects of our
emiiincal knowledge ; and they cooperate, equally and in like man-
ner, to the progress of that knowledge, partly by establishing,
partly by correcting, partly by amplifying it. Under observation,
therefore, is not to be undei*stood a common or unlearned experi-
ence, which obtrudes itself upon every one endowed with the
ordinary faculties of Sense and Understanding, but an intentional
and continued application of the faculties of Perception, combined
with an abstractive and reflective attention to an object or class of
objects, a moixj accurate knowledge of jvhich, it is proposed, by the
observation, to accomplish. But in order that the observation
sliould accomplish this end, — more especially when the objects are
8 Fragmentum t Silla. Vide Corpus Poetarum Latinorum, vol. ii. p. 1G18, Loud. 1713. — £o
I.KCT. XXXU. LOGIC. 446
numerous, and a systematic complement of cognitions is the end
proposed, — it is necessary that we should know
praecognita of Ob- certain prjBCOi^nita, — 1°. What we ought to
observe ; 2°. How we ought to observe ; and S".
By what means are the data of observation to be reduced to sys-
tem. The first of these concerns the Object; the second, the Pro-
cedure ; the third, the scientific Completion, of the observations.
It is proper to make some general observations in regard to these,
in their order; and first, of the Object of observation, — the what
we ought to observe.
"The Object of Observation can only be some given and deter-
minate phjenomenon, and this phsenomenon ei-
Firet, — The Object thcr an external or an internal. Thnough observa-
T-u- r I ij tion, whether external or internal, there are four
Th» fourfold. ' '
several cognitions which we propose to compass,
— viz., to ascertain — 1°. What the Phaenomena themselves are; 2".
What are the Conditions of their Reality ; 3°. What are the Causes
of their Existence ; 4°. What is the Order of their Consecution.
"In regard to what the phaenomena themselves are (quid sint),
that is, in regard to what constitutes their pecu-
1°. What the Phaj- jj^^, nature, — this, it is evident, must be the
nomena are. . „.,..,.
primary matter of consideration, it being always
supposed that the fact (the an sit) of the phsenomenon itself has
been established.^ To this there is required, above all, a clear and
distinct Presentation or Representation of the object. In order to
obtain this, it behooves us to analyze, — to dis-
in their individual member, the constituent parts of the object,
pecu lan es an con. ^^^ ^^ take into proximate account those char-
trasta. \
acters which constitute the object, that is, which
make it to be what it is, and nothing but what it is. This being
performed, we must proceed to compare it with other objects, and
with those especially which bear to it the strongest similarity,
taking accurate note always of those points in which they recipro-
cally resemble and in which they reciprocally disagree.
"But it is not enough to consider the several phaenomena in their
individual peculiarities and contrasts, — in what
As under determi- ^j^gy ^^,^^ ^^^ J^ ^,\^^^ ^j^py are not, — it is also
nate genera and spe- . . , . , i ^ ^ • ..
gj^ requisite to bring them under determinate gen-
era and species. To this end we must, having
obtained (as previously prescribed) a clear and distinct knowledge
of the several phaenomena in their essential similarities and differ-
ences, look away or abstract from the latter, — the differenc^is, and
I Better the Aristotelic questions, — ^n Sit, etc. [See Lectures on Metaphysics, p. 4V - Ed.]
446 LOGIC. Lect. xxxn.
comprehend the former, — the similarities, in a compendious and
characteristic notion, under an appropriate name.
" When the distinctive peculiarities of the }>haBnomena have been
thus definitively recognized, the second ques-
*• *•'.!. 'LT/' tion emerges, — What are the Conditions of
tions of their Reality. . .
their Reality. These conditions are commonly
called Requisites, and under requisite we must understand all that
must have preceded, before the phaenomena could follow. In order
to discover the requisites, we take a number of analogous cases, or
cases similar in kind, and inquire what arc the circumstances under
which the phasnomenon always arises, if it does arise, and what are
the circumstances under which it never arises; and then, after a
competent observation of individual cases, we construct the general
judgment, that the phaenomenon never occurs unless this or that
other phaenomenon has preceded, or at least accompanied, it. Here,
however, it must be noticed, that nothing can be viewed as a requi-
site which admits of any, even the smallest, exception.
"The requisite conditions being discovered, the third question
arises, — What are the Causes of the Phaenom-
3" What the Causes ^^^^ According to the current doctrine, the
of the rhsenomena. ^
causes of phaenomena are not to be confounded
with their requisites; for although a phaenomenon no more occurs
without its requisite than without its cause, still, the requisite being
given, the phaenomenon does not necessarily follow, and, indeed,
very frequently does not ensue. On the contrary, if the cause
occurs, the phaenomenon must occur also. In other words, the
requisite or condition is that without which the phaenomenon never
is ; the cause, on the other hand, is that through which it always is.
Thus an emotion of pity never arises without a knowledge of the
misfortune of another; but so little does this knowledge necessitate
that emotion, that its opposite, a feeling of rejoicing, complacency,
at such suffering may ensue ; whereas the knowledge of another's
misfortune must be followed by a sentiment of pity, if we are pre-
disposed in favor of the person to whom the misfortune has oc-
curred. In this view, the knowledge of another's misfortune is
only a requisite; whereas our favorable predisposition constitutes
the cause. It must, however, be admitted, that in different rela-
tions one and the same circutnstance may be both requisite and
cause ;"^ and, in point of fact, it would be more correct to consider
the cause as the whole sura of antecedents, without which the phae-
nomenon never does take place, and with which it always must.
1 Easer, Logik, { 148. — Ed.
Lect. XXXII. LOGIC. 447
What are commonly callecl requisites, are thus, in truth, only partial
causes ; what are callecl causes, only proximate requisites.
"In the fourth place, having ascertained the essential qualities, —
• the Conditions and the Causes of pluEnomena,
4». What the Order _^ ^^^^ question emerges, — What is the
of tlieir Consecution. r^ -, • i-ii .^ ,« ti-
Order in which they are manifested ? and this
being ascertained, the observation has accomplished its end. This
question applies either to a phaenomenon considered in itself^ or to a
j)ha?nomenon considered in relation to others. In relation to itself,
(ho question concerns only the time of its origin, of its continuance,
and of its termination ; in relation to others, it concerns the recip'
rocal consecution in which the several phaenomena api^ear." '
"We now go on to the Second Pra9cognitum, — the Manner of
Observation, — How we are to observe. What
Second, - The Man- ^^ ^^^^,^ hitherto spoken of — the Object — can
ner of Observation. '■ n •
be known only in one way, — the way of Scien-
tific Observation. It therefore remains to be asked, — How must
the observation be instituted, so as to afford us a satisfactory result
in regard to all the four sides on which it behooves an object to be
observed ? In the first place, as preliminary to
. roper g ate o observation, it is required that the observins:
the observing mind. , , -^ ^
mind be tranquil and composed, be exempt
from prejudice, partiality, and prepossession, and be actuated by
no other interest than the discovery of truth. Tranquillity and
composure of mind are of peculiar importance in our observation of
the phaenomena of the internal world; for these phrenomena are not,
like those of the external, perceptible by sense, enclosed in space,
continuous and divisible; and they follow each other in such num-
bers, and with such a rapidity, that they are at best observable with
difficulty, often losing even their existence by the interference of
the observing, — the reflective energy, itself. But that the obser-
vation should be always conducted in the calm and collected state
of mind required to purify this condition, we must be careful to
obtain, more and more, a mastery over the Attention, so as to turn
it with full force upon a single aspect of the phenomena, and, conse-
quently, to abstract it altogether from every other. Its proper func-
tion is to contemplate the objects of observation tranquilly, continu-
ously, and without anxiety for the result ; and this, likewise, without
too intense an activity or too vigorous an application of its forces.
Bi;t the observation and concomitant energy of attention will be
without result, unless we previously well consider what pi-ecise
object or objects we. are now to observe. Nor will our experience
1 Esser, Logik, § 148. — Ed.
44s LOGIC. Lect. XXXIL
obtain an answer to the question proposed for it to solve, unless
that question be of such a nature as will animate
2^, Conditions of the i]^q observing faculties by some stimixlus, and
question to be deter- . ,, , . • . t ,• -nxi i •
. . , ^. . give them a determinate dirc^'tion. Where this
mined by the observa- p
tioM. is not the case, attention does not effect any-
thing, nay, it does not operate at all. On this
account such psychological questions as the following : What takes
place in the process of Self-consciousness, — of Perception, — of
Vision, — of Hearing, — of Imagination, etc., — cannot be an-
swered, as thus absolutely stated, that is, without reference to
some determinate object. But if I propose the problem, — What
takes place when I see this or that object, or better still, when I •seo
this table, — the attention is stimulated and directed, and oven a
child can give responses, which, if properly illustrated and ex-
plained, will afford a solution to the problem. If, therefore, the
question upon the object of observation be too vague and general,
so that the attention is not suitably excited and applied, — thia
question must be divided and subdivided into others more par-
ticular, and tliis process must bo continued until wc reach a ques-
tion which affords the requisite conditions. We should, therefore,
detoiinine as closely as possible the object itself and the phases in
whicii we wish to observe it, separate from it all foreign or adventi-
tious parts, resolve every question into its constituent elements,
enunciate each of these as specially as ])ossible, and never couch it
in vague and general expressions. But here we must at tlie same
time take care that the object be not so torn and mangled that the
attention feels no longer any attraction to the several parts, or that
the several parts can no longer be viewed in their natural connec-
tion. So much it is possible to say in general, touching the Man-
ner in which observation ought to be carried on ; what may further
be added under this head, depends upon the particular nature of
tlve objects to be observed." *
"In this manner, then, must we proceed, until all lias been
accomplished wjiich the problem, to be answered by the observa-
tion, pointed out. When the observation is concluded, an accurate
)('<'ord or notation of what has been observed is of use, in order to
I'liable us to supply Avhat is found wanting in our subsequent obser-
\ :ition. If we have accumnlated a considerable apparatus of re-
sults, in relation to the object we observe, it is proper to take a
survey of these ; from what is found defective, new questions must
be evolved, and an answer to these sought out through new obser-
1 Esser, Logik, f 149. — Ed
Lkct. :: :ixii. logic. 449
vations. When the inquiry lias nttnined its issue, a tabular view of
all the observations made upon the subject is convenient, to afford
a conspectus of the whole, and as an aid to the memory. But how
(and this is the Third Precognition) individual
Third, — The means observations are to be built up into a systematic
by which the data of ^j^^j^^ j^ ^^ ^^ sou^ht for partly from the nature
Observation are to be /. • . , i /^ i />
rwiuced to System. ^^ science in general, partly from the nature of
the particular empirical science for the constitu-
tion of which the observation is applied. Nor is what is thus sought
difficult to find. It is at once evident, that a synthetic arrangement
is least applicable in tlje empirical sciences. For, anterior to obser-
vation, the object is absolutely unknown ; and it is only through
observation that it becomes a matter of science. We can, therefore,
only go to work in a problematic or interrogative manner, and it
is impossible to commence by assertory propositions, of which we
afterwards lead the demonstration. We must, therefore, determine
the object on all sides, in so far as observation is competent to this;;
we must analyze every question into its subordinate questions, and
each of these must find its answer in observation. The systematic
order is thus given naturally and of itself; and in this procedure it
is impossible that it should not be given. But for a comprehensive
and all-sided system of empirical knowledge, it is not sutficienl to-
possess the whole data of observation, to have collected these to-
gether, and to have arranged them according to some external prin-
ciple ; it is, likewise, requisite that we have a thorough-going prin-
ci])le of explanation, even though this explanation be impossible in
the way of observation, and a power of judging of the data, ac-
cording to universal laws, although these universal laws may not be
discovered by experience alone. These two ends are accomplished
by different means. The former we compass by the aid of Hypoth-
esis, the latter, by the aid of Induction and Analogy."^ Of theso
in detail. In regard to Hypothesis, I give you the following,
paragraph.
%. CVII. When a phsenomenon is presented, which can be-
explained by no principle afforded through
Par. CVII. Hypoth- Experience,' We feel discontented and un-
esia, — what. * ^
easy ; and there arises an effort to discover •
gome cause which may, at least provisorily, account for the
outstanding phaenomenon ; and this cause is finally recognized
as valid and true, if, through it, the given phaenomenon is-
1 Esser, Logik, J 150. — Ed.
57
450 LOGIC. Lect. XXXlL
found to obtain a full and perfect explanation. The judgment
in which a phaenomenon is referred to such a problematic
cause, is called an Hypothesis}
Hypotheses have thus no other end than to satisfy the desire of
the mind to reduce the objects of its knowledge
\p ication. ^^ unity and system : and they do this in recall-
Hypothesis, — its end. . ■' ^ ' •/ ^ ^
ing them, ad interim, to some principle, through
which the mind is enabled to comprehend them. From this view
of their nature, it is manifest how far they are permissible, and how
far they are even useful and expedient ; throwing altogether out of
account the possibility, that what is at first assumed as hypothetical,
may, subsequently, be proved true.
When our experience has revealed to us a certain correspondence
among a number of objects, we are determined, by an origmal prin-
ciple of our nature, to suppose the existence of a more extensive
conespondence than our observation has already proved, or may
ever be able to establish. This tendency to generalize our knowl-
edge by the judgment, — that where mucli has been found accord-
ant, all will be found accordant, — is not properly a conclusion
deduced from premises, but an original principle of our nature,
which we may call that o^ Logical^ or perhaps better, that of I* hila-
sophical, Presumption. This Presumption is of two kinds; it i?
either Induction or Analogy, which, though usually confounded,
are, however, to be carefully distinguished. I shall commence th<»
consideration of these by the following paragraph.
% CVIII. If we have uniformly observed that a number of
objects of the same class (genus or species)
Par. cviii. Indue- posscss in couimon a certain attribute, we
tlon and Analogy. '
are disposed to conclude that this attribute
is possessed by all the objects of that class. This conclusion is
properly called an Inference of Induction. Again, if we have
observed that two or more things agree in several internal and
essential characters, we are disposed to conclude that they
agree, likewise, in all other essential characters, that is, that
they are constituents of the same class (genus or species).
This conclusion is properly called an Inference of Analogy.
The principle by which, in cither case, we are disposed to
extend our inferences beyond the limits of experience, is a nat-
ural or ultimate principle of intelligence ; and may be called
I EsMr, Logik, i 151 Ci. Ltcturti on Xtiaphysics, p 117 et aeq. — Ed
Lect. XXXII. LOGIC. 451
the principle of Logical^ or, more properly, of Philosophicai
Presumption}
"The reasoning by Induction and the reasoning by Analogy
have this in common, that they both conclude
Explication. from something observed to something not ob-
Induction and Anal- i /• ^i • -.i • ^ ^i •
, . served ; from somethmi; within to something
ogy, — their agree- ^ o o
ment and diiTerence. beyond the Sphere of actual experience. They
differ, however, in this, that, in Induction, that
which is observed and from which the inference is drawn to that
which is not observed, is a unity in plurality ; whereas, in Analogy,
it is a plurality in unity. In other words, in Induction, we look to
the one in the many ; in Analogy we look to the many in the one :
and while in both we conclude to the unity in totality, we do this,
in Induction, from the recognized unity in plurality, in Analogy,
from the recognized plurality in unity. Thus, as induction rests
upon the principle, that what belongs (or does not belong) to
many things of the same kind, belongs (or does not belong) to all
things of the same kind; so analogy rests upon the principle, —
that things which have many observed attributes in common, have
other not observed attributes in common likewise."^ It is hardly
necessary to remark that we are now speaking of Induction and
Analogy, not as principles of Pure Logic, and as necessitated by
the fundamental laws of thought, but of these as means of acquir-
ing knowledge, and as legitimated by the conditions of objective
reality. In Pure Logic, Analogy has no place, and only that induc-
tion is admitted, in which all the several parts are supposed to
legitimate the inference to the whole. Applied Induction, on the
contrary, rests on the constancy, — the uniformity of nature, and
on the instinctive expectation we have of this stability. This con-
stitutes what has been called the principle oi Logical Presumption^
though perhaps it might, with greater propriety, be called the prin-
ciple of Philosophical Presumption. We shall now consider these
severally ; and, first, of Induction.
An Induction is the enumeration of the parts, in order to /egiti-
mate a iudsrment in regard to the whole.^ Now,
Induction,— what. , J & f . ^. . -, . .
the parts may either be individuals or particu-
lars, strictly so called. I say strictly so called, for you are aware
1 Cf. Esser, Logik, §J 140, 152. Krug, hogik, H 3 [Cf. Ahu AU (Avicenncp) Viri Docti, De Log-
166,167,168.— Ed. [Wolf, Pkil. Kationalis, § 479. ica, Poema, 1. 190. (In Schmcilders, Documenla
Reusch, Systfma Logicum, §§ 572,573. Nunne- P/iilosophicF: Arabum, p. 36-) Bonn!B,18S&. Zaba-
Siu8, De Constitutione Artis DiaUctica, p. 126.] rella. Opera Logica, De Natura Logica, Li. i. «
a Esser, Logik, i 152. — Ed. 18, p. 46.]
452
LOGIC.
lkct. xxxn.
Of two kinds, — In-
dividual and Special.
vidual Induction
that the term particular is very commonly employed, not only to
denote the species, as contained under a genus, but, likewise, to
denote the individual, as contained under a species. Using, how-
ever, the two terms in their proper significations, I say, if the parts
are individual or singular things, the induction is then called Indi-
vidual; whereas if the parts be species or subal-
tern genera, the induction then obtains the
name of Special. An example of the Indi-
is given, were we to argue thus, — Mercury^
Venus, the Earth, Mars, etc., are bodies in themselves o^yaque, and
which borroio their light from the sun. But Mercury, Venus, etc.,
are planets. Therefore, all planets are opaque, and borroio their
ligMfrom the sun. An example of the special is given, were we to
argue as follows, — Quadrupeds, birds, fishes, the amphibia, etc, ctO
have a nervous system,. But quadrupeds, birds, etc., are animah.
Therefore all animals (though it is not yet detected in some) have
» nervous systein. Xow, here it is manifest that Sj^ecial rests upon
Individual induction, and that, in the last result, all induction is
individual. For we can assert nothing concerning species, unless
what we assert of them has been previously observed in their con-
•tituent singulars.'
For a legitimate Induction there are requisite at least two condi-
tions.- In the fii-st place, it is necessary. That
the partial (and this word I use as including
both the terms individual and particular), — I
say, it is necessary that the partial judgments
out of which the total or general judgment is inferred, be all of the
same quality. For if one even of the partial judgments had an
opposite quality, the whole induction would be subverted. Hence
it is that we refute universal judgments founded on an imperfect
induction, by bringing what is called an instance {instantia), that
is, by adducing a thing belonging to the same class or notion, in
reference to which the opposite holds true. For example, the
general assertion, All dogs bark, is refuted by the instance of th«
dogs of Labrador or California (I forget which), — these do not
bark. In like manner, the general assertion, No quadruped is ovi-
parous, is refuted by the instance of the Ornithorhynchus Para-
doxus. But that the universal judgment must have the same
quality as the partial, is self-evident; for this judgment is simply
the assertion of something to be true of all which is true of
many.
The second condition required is, That a competent number
The two conditions
of legitimate Induc-
tion,—.First.
1 Krng, Logik, ( 167. Anm. — Bd.
» Esser, Logik, f IfiS. — £l>.
Jtwer. xxxu. LOGIC. 45$
<rf the partial objects from which the induction departs should have
been observed, for otherwise the comprehensioo
of other objects «nder the total judgment would
be rash.' What is the number of such ylyects, vvliich amounts to u
Competent induction, it i,s not jxjssible to say in general. In some
ca«e«, the observation of a very few parti<;ular or individual exam-
pleaB is sufficient to warrant an assertion in regard to the whole
class; in others, the total judgment is hardly cotnpctent, until our
observation has gone through each of its constituent parts. This
distinction is founded on the difference of essential and unessential
characters. If the character be essential to the several objects, a
eomparatively limited observatic* is necessary to legitimate our
geBei^al conclusion. For example, it would require a far less induc-
tion to prove that all animals breathe, than to prove that the mam-
malia, and the mammalia alone, have lateral lobes to the cerebellum.
For the one is seen to be a function necessary to animal life ; the
other, as far as our present knowledge reaches, appears only as an
arbitrary concomitant. The difference of essential and accidental
]&, however, one itself founded on induction, and varies according
to the greater or less perfection to which this has been carried. In
the progress of science, the lateral lobes of the cerebellum may
appear to future physiologists as necessary a condition of the func-
tion of suckling their young, as the organs of breathing appear to
UB of circulation and of life.
To sum up the Doctrine of Induction, — "This is more certain,
1°, In proportion to the number and diversity
I ummary o t e ^^ ^^^ objccts observed : — 2°, In proportion to
doctrine of Induction. *^ . _ .
the accuracy with which the observation and
©omparison have been conducted; — 3°, In proportion as the agree^
ment of the objects is clear and precise ; — and, 4°, In proportion
a« it has been thorouglily explored, whether there exist exception*
or not." ^
Almost all induction is, however, necessarily imperfect; and
L^ic can inculcate nothing more important on the investigatoiis
of nature than that sobriety of mind, which regards all its 'past
observations only as hypothetically true, only as relatively com-
plete, and which, consequently, holds the mind open to every new
observation, which may correct and limit its former judgments.
So much for Induction ; now for Analogy. Analogy, in genei-al,
means proportion, or a similarity of relation^^-.
Analogy, -what. ^, . , , . „
Ihus, to judge analogically, or accordmg to
aaalogy, is to judge things by the eimilarity of their relations.
I Esser, Logik. i 152— Ed. 2 Esser. Logik, { 162. — Ed.
454 LOGIC. lect. xxxn.
Thus when we judge that as two is to four, so is eight to sixteen,
we judge that they are analogically identical ; that is, though the
sums in other respects are different, they agree in this, that as two
18 the half of four, so eighths the half of sixteen.
In common language, however, this propriety of the term is not
preserved. For hy analogy is not always meant merely hy propor-
tion^ but frequently hy comparison — hy relation, or simply by simi-
larity. In so far as Analogy constitutes a particular kind of rea-
soning from the individual or particular to the universal, it signifies
an inference from the partial similarity of two or more things to
their complete or total similarity. For example, — This disease
corresponds in many symptoms with those we have observed in
typhus fevers ; it will, therefore^ con'espond in all, that is, it is a
typhus fever}
Like Induction, Analogy has two essential requisites. In the
first place, it is necessary that of two or more
- ..^. ^° !f^" '* things a certain number of attributes should
oonditions, — First. °
have been observed, in oi-der to ground the
inference that they also agree in those other attributes, which it
has not yet been ascertained that they possos.s. It is evident that
in proportion to the number of points observed, in which the
things compared together coincide, in the same proportion can it
be with safety assumed, that there exists a common principle in
these things, on which depends the similarity in the points known
»s in the points unknown.
In the second place, it is required that the predicates already
observed should neither be all negative nor all
contingent ; but that some at least should bo
positive and necessary. Mere negative characters denote only what
the thing is not ; and contingent characters need not be present in
the thing at all. In regard to negative attributes, the inference,
that two things, to which a number of qualities do not belong, and
which are, consequently, similar to each other only in a negative
point of view, — that these things are, therefore, absolutely and
positively similar, is highly improbable. But that the judgment in
reference to the compared things (say A and X) must be of the
same quality (i. e. either both affirmative or both negative), is self-
evident. For if it be said A is B, X is not B, A is not C, X is C;
their harmony or similarity is subverted, and we should rather bo
warranted in arguing their discord and dissimilarity in other points.
I Of. Krug, Z/>^, ( 168. Anm. — Ed. [Con- Avicenna (in Schmbldera, Doeumenta PkiL
riillno, VArt de Raisonner, L. iv. ch. 3, p. 159. Arabum, p. 36.) Whately, Rhetoric, p. 74.]
Lkct. XXXn. LOGIC. 455
And here it is to be noticed that Analogy diifers from Induction in
this, that it is not limited to one quality, but that it admits of a
mixture of both.
In regard to contingent attributes, it is equally manifest that the
analogy cannot proceed exclusively upon them. For, if two things
coincide in certain accidental attributes (for example, two men in
respect of stature, age, and dress), the supposition that there is a
common principle, and a general similarity founded thereon, is very
unlikely.
To conclude : Analogy is certain in proportion, 1°, To the num-
ber of congruent observations ; 2°, To the num-
Summary of the ^^^ ^^ congruent characters observed: 3°, To
doctrine of Analogy. .
the importance of these characters and their
essentiality to the objects; and, 4", To the certainty that the char-
acters really belong to the objects, and that a partial correspond-
ence exists.* Like Induction, Analogy can only pretend at best to
a high degree of probability ; it may have a high degree of cer-
tainty, but it never reaches to necessity.
Comparing these two processes together: — " The Analogical is
distinguished from the Inductive in this — that
Induction and Anal- Induction regards a single predicate in many
. Subjects as the attribute Z in A, in B, in C, in
D, in E, in F, etc. ; and as these many belong
to one class, say Q ; it is inferred that Z will, likewise, be met with
in the other things belonging to this class, that is, in all Qs. On
the other hand. Analogy regards many attributes in one subject
(say m, n, o, p, in A) ; and as these many are in part found in
another subject (say m, and n, in B), it is concluded that, in that
second thing, there will also be found the other attributes (say o
and p). Through Induction we, therefore, endeavor to prove that
one character belongs (or does not belong) to all the things of a
certain class, because it belongs (or does not belong) to many
things of that class. Through Analogy, on the othep hand, we
seek to prove that all the characters of a thing belong (or do not
belong) to another or several others, because many of these charac-
ters belong to this other or these others. In the one it is pro-
claimed,— One in many, therefore one in all. — In the other it is
proclaimed, — Many in one, therefore all in one." ^
"By these processes of Induction and Analogy, as observed, we
are unable to attain absolute certainty ; — a great probability is all
1 EsBer, Logik, S 152. Cf Krug, Logik, } 168. Anm. — Ed.
2 Krug, Log-ii, { 168. Anm. — E©.
466
LOGIC.
LarcT. XXXII.
Indnction and Anal
ogy do not &3brd ab-
solute certainty.
that tre can reach, and this for the simple reason, that it is impossi-
ble, under any condition, to infer the unob-
served from the observed, — the whole from
any proportion of the parts, — in the way of
any rational necessity. Even from the requi-
sites of Induction and Analogy, it is manifest that they bear the
stamp of tincertainty ; inasmuch as they are unable to determine
liow many objects or how many characters must be observed, m
order to draw the conclusion that the case is the same with all the
otiier objects, or with all the other characters. It is possible only
in one way to raise Induction and' Analogy from mere probability
to complete certainty, — viz., to demonstrate that the principles
which lie at the root of these processes, and which we have already
stated, are either necessary laws of thought, or necessaiy laws of
nature. To demonstrate that they are necessary laws of thought is
impossible ; for Logic not only does not allow inference from many
to all, but expressly rejects it. Again, to demonstrate that they
are necessary laws of nature is equally impossible. This has in-
deed been attempted, from the uniformity of nature, but in vain.
For it is incompetent to evince the necessity of the inference of
Induction and Analogy from the fact denominated the laio (^
nature ; seeing that this law itself can only be discovered by the
way of Induction and Analogy. In this attempted demonstration
there is thus the most glaring petitio principii. The result which
has been previously given remains, therefore, inUict: — Induction
and Analogy guarantee no perfect certainty, but only a high degree
of probability, while all probability rests at best upon Induction
and Analogy, and nothing else." *
1 Eeser, Logik, § 162.— Ed. [On history and
doctrine of tlus Logic of Probabilities, see
Leibnitz, Nouceaux Essais. L. iv. ch. xv. p.
425, «d. Raspe. Wolf, Phil. Rat. f 564 <( stg.
riatner, Phil. Aphorismen, f 701 (old edit.) f
694 (new edit.). Zedler, Lexikon. v.Wahrschein-
Hek. Walch, Lfxikon, Ibid. Lambert, iVirK**
Orgtmon, ii. p. 818 et seq. Reusch, SysUma Log-
tctttn, i 653 et seq. Hollmann, Lo^iea, i 215 et
seq. Uoffbauer, Anfangsgr^tnde der LogiJc, ^
422 et seq. Bolzano, Logii, vol. ii. i 161, vol.
iii. § 317. Bachmann, Logik, $ 229 et stq.
Fries, Logik, f 96 «t ieq. Frevost, Essais ile
Philosophie, ii. L. i. part iii. p. 56. Kant, Logik,
Einleitung x. Jacob, Grundriss drr AUgemei-
nen Logik, } 358, p. 181 et sfq., 1800, Halle.
Metz, IiistUutioiui Lqgita, i 280 et seq.fp. 171,
1796.]
LECTURE XXXIII.
MODIFIED METHODOLOGY.
SECTION I. — OF THE ACQUISITION OF KNOWLEDGE
I. EXPERIENCE. — B. FOREIGN : — ORAL TESTIMONY —
ITS CREDIBILITY.
Having, in our last Lecture, terminated the Doctrine of Empiri-
cal Knowledsre, considered as obtained Iramedi-
Fomgn Experience. i . i • r
ately, — that is, through the exercise of our own
powers of Observation, — we are now to enter on the doctrine of
Empirical Knowledge considered as obtained Mediately, — that is,
through the Experience of Other Men, The following paragraph
will afford you a general notion of the nature and kinds of this
knowledge.
^l' CIX. A matter of Observation or Empirical Knowledge
can only be obtained Mediately, that is, by
Bar. CIX. Testimony. • j- -j i r *l, .il, u
one individual irom another, through an
enouncement declaring it to be true. This enouncement is
called, in the most extensive sense of the word, a Witnessing
or Testimony {testimojiiitm) ; and the person by whom it is
made is, in the same sense, called a Witness, or Testifier
(testis). The object of the testimony is called the J^act (fac-
tum) ; and its validity constitutes what is styled Historical
Credibility (credibilitas historica). To estimate this credi-
bility, it is requisite to consider — 1°, The Subjective Trust-
worthiness of the Witnesses (fides testium), and 2°, The Ob-
jective Probability of the Fact itself. The former is founded
partly on the Sincerity, and paitly on the Competence, of the
Witness. The latter depends on the Absolute and Relativ<;
Possibility of the Fact itself. Testimony is either Immediate
or Mediate. Immediate, where the foct reported is the object
d8
458 LOGIC. lect. xxxm.
of a Personal Experience ; Mediate, where the fact reported is
the object of a Foreign Experience.*
"It is manifest that Foreign Experience, or the experience of
other men, is astricted to the same laws, and its
Explication. . i i i ...
certainty measured by the same criteria, as the
experience we carry through oui-selves. But the experience of the
individual is limited, when compared with the experience of the
species; and if men did not possess the means of communicating
to each other the results of their several observations, — were they
unable to cooperate in accumulating a stock of knowledge, and in
carrying on the progress of discovery, — they would never have
risen above the very lowest steps in the acquisition of science.
But to this mutual communication they are competent ; and each
individual is thus able to appropriate to his own benefit the experi-
ence of his fellow-men, and to confer on them in return the advan-
tages which his own observations may supply. But it is evident
that this reciprocal communication of their respective experiences
among men, can only be effected inasmuch as one is able to inform
another of what he has himself observed, and that the vehicle of
this information can only be some enouncement in conventional
signs of one character or another. The enouncement of what has
been observed is, as stated in the paragraph, called a witnessing^ — a
hearing witness, — a testimony, etc., these, terms being employed in
their wider acceptation ; and he by whom this declaration is made,
and on whose veracity it rests, is called a witness, voucher, or testi-
fier {testis)^^ The term testhnony, I may notice, is sometimes, by
an abusive metonym, employed for witness ; and the word evidence
is often ambiguously used for testimony, and for the bearer of testi-
mony, — the witness.
" Such an enouncement, — such a testimony, is, however, neces-
sary for others, only when the experience which
The proper object of j^ communicates is beyond the compass of their
festimony. , " . «
own observation. Hence it follows, that mat-
ters of reasoning are not proper objects of testimony, since mattera
of reasoning, as such, neither can rest, nor ought to rest, on the
observations of othei-s ; for a proof of their certainty is equally
comj)etent to all, and may by all be obtained in the manner in
which it was originally obtained by those who may bear witness to
their truth. And hence it further follows, that mattei-s of experi-
ence alone are proper objects of testimony; and of mattere of
experience tlionisclves, such only as are beyond the si)here of our
1 Kmg, Logik, S 172. — Ed. [Cf. Scheibler, ibpica, c. 31.] 8 Esser, Logik, | 153. — Ed.
Lect. XXXin. LOGIC. 459
personal experience. Testimony, in the strictest sense of the term,
therefore, is the communication of an experience, or, what amounts
to the same thing, the report of an observed phaenomenon, made
to those whose own experience or observation has not reached so
far.
"The object of testimony, as stated in the paragraph, is called
the fact; the validity of a testimony is called
The Fact. historical credibility. The testimony is either
Historical credibil- • j-^ ^• . t t^ i ^i
immediate or mediate. Immediate, when the
ity. . . '
witness has himself observed the fact to which
he testifies ; mediate, when the witness has not himself had experi-
ence of this fact, but has received it on the testimony of others.
The former, the immediate witness, i? com-
ye-witness. tnonly Styled an eye-ioitness (testis oculatus) ;
Ear-witness. J J it , \ / ■>
and the latter, the mediate witness, an ear-
witness {testis auritas). The superionty of immediate to mediate
testimony is expressed by Plautus, ' Pluris est oculatus testis unus,
quam auriti decem.' ^ These denominations, eye and ear witness,
are however, as synonyms of immediate and mediate witness, not
always either applicable or correct. The person on whose testi-
' mony a fact is mediately reported, is called the
The Guarantee. *' , ^ ' . .
guarantee, or he on whose authority it rests;
and the guarantee himself may be again either an immediate or a
mediate witness. In the latter case he is called a second-hand or
intermediate witness; and his testimony is commonly styled hearsay
evidence. Further, Testimony, whether immediate or mediate, is
either partial or complete; either consistent or
Testimonies — Par- contradictory. These distinctions require no
1 , ^""P *^ ^' "'"■ comment. Finally, testimony is either direct or
sistenl, Contradictory. •" •'
indirect; direct, when the witness has no mo-
tive but that of making known the fact ; indirect, when he is actu-
ated to this by other ends," ^
The only question in reference to Testimony is that which
regards its Credibility ; and the question con-
Division of the sub- ceming the credibility of the witness may be
ject: I. Credibility of , -, i -, , , . y r^ ^^
Testimony in general. Comprehended Under that touching the Credi-
II. Credibility of Tea- bility of Testimony. The order I shall follow
timony in its particu- j^ ^^iQ subsequent observations is this, — I shall,
ate andMediatl!"'^'^'' ^" *^® ^^'^^ P^^^®' Consider the Credibility of
Testimony in general ; and, in the second, con-
sider the Credibility of Testimony in its particular forms of Imme-
diate and Mediate,
1 IVufu&ntiw, II. vi. 9. Cf. Krug, LogOr, § 172. Anm. — Ed. 3 Esser, iofft*, § 153. — Ed.
460 LOGIC. Lect. XXXIIL
FtfBt, then, in regard to the Credibility of Testimony in general j
— When we inquire whether a certain testimony is, or is not,
deserving of fixKlit, there are two tilings to be considered : 1°, The
Object of the Testimony, that is, the feet or facts for the truth of
whicli tlie Testimony vouches; and, 2°, Tlie Subject of the Testi-
mony, tbat is, the jKirson or persons by wliom the testimony is
borne. Th« question, thercfoi'e, concerning the Credibility of Tes-
timony, thus naturally subdivides itself into two. Of these ques-
tions, the first asks, — What are the conditions of the credibility
of a testimony by reference to what is testified, that is, in relation
to the Object of the testimony ? The second asks, — What are the
conditions of the credibility of a testimony by i-eferenoe to him
who testifies, that is, in relation to the Sijbject of the testimony?^
Of these in their order.
On the first question. — " In regard to the matter testified, that
is, in regard to the object of the testimony ; it
. re 1 1 1 > o . g^^ ^^ ^jj ^ requisite condition, that what is
li'Stiraony in general. ' ^ ♦ _
1°, Hie Object of Uie reported to be true should be possible, both
Testimony. absolutely, or as an object of tlie Elaborative
J'',. ^^'''^''^^ ^**''" Fr.culty, 'and relatively, or as an object of the
Piesentative Faculties, — Perception, External
CM* Internal, A thing is possible absolutely, or in itself, when it
can be construed to thought, that is, when it is not inconsistent
with the logical laws of thinking ; a tiling is relatively possible as
an object of Perception, External or Internal, when it can affect
Sense or Self-consciousness, and, through such affection, determine
its apprehension by one or oth<H' of these faculties. A testimony
is, therefore, to be unconditionally rejected, if the fact which it
rejiorts be eitlicr in itself impossible, or impossible as an object of
the Presentative Faculties. But the impossibility of a thing, as an
object of these faculties, must be decided either
riivficai and Jieta- upon ])hysical, or upon metaphysical, principles.
1 iy«M5a ni|>oi-8i i- ^ tiijng js physically impossible as an object of
sense, when the existence itself, or its percep-
t«»n fey ««, M, by the laws of the mateiial woi-ld, impossible. It is
mctaphysicaMy impossible, when the object itself, or its perception,
i« possible neither through a natural, nor through a supei-natural,
ageiicy. But, to establish the iiRta]ihysical impossibility of a
thing, it is not fiuflicient that its existence cannot be explained by
tbe ordinary laws of natui-e, or even that its existence should
appear reptigtiant wifh these laws ; it is requisite that an universal
and immutable law of nature should have been demonstrated to
i or. Emet, Moe*, f Mt — Bd.
Lkct. XXXm. LOGIC. 461
exist, and that this law would be subverted if the fact in question
were admitted to be physically possible. In like manner, to consti-
tute the metaphysical impossibility of a thing, it is by no means
enough to show that it is not explicable on natural laws, or even
that any natural law stands opposed to it ; it is further requisite to
prove that the intervention even of supernatural agency is incom-
petent to its production, that its existence would involve the viola-
tion of some necessary principle of reason.
"To establish the credibility of a testimony, in so far as this is
regulated by the nature of its object, there is,
Relative Possibility ijggj^jgg ^^^ f ^f ^^e absolute possibilitv of
of an object. . ^ . ^ •
this object, required also a proof of its relative
possibility ; that is, there must not only be no contradiction be
tween its necessary attributes, — the attributes by which it must be
thought, — but no contradiction between the attributes actually
assigned to it by the testimony. A testimony, therefore, which,
qua testimony, is self-contradictory, can lay no claim to credibility ;
for what is self-contradictory is logically suicidal. And here the
only question is, — Does the test'imonj, qtia testimony, contradict
itself? for if the repugnancy arise from an opinion of the witness,
apart from which the testimony as such would still stand undis-
proved, in that case the testimony is not at once to be repudiated
as false. For example, it would be wrong to reject a testimony to
the existence of a thing, because the witness had to his evidence
of its observed reality annexed some conjecture in regard to its
origin or cause. For the latter might well be shown to be absurd,
and yet the former would remain unshaken. It is, therefore,
always to be observed, — that it is only the self-contradiction of
a testimony, qua testimony, that is, the self-contradiction of the
fact itself, which is peremptorily and irrevocably subversive of its
eredibility.
" We now proceed to the second question ; that is, to consider in
general the Credibility of a Testimony by ref-
20, The Subject of gj-g^ce to j^g Subject, that is, in relation to the
the Testimony, or per- "^
sonai trustworthiness Personal Trustworthiuess of the Witness. The
of the Witness. This trustworthiness of a witness consists of two ele-
ceawsts of two eie- ments or conditions. In the first place, he must
ments: — (a) Honesty , .„. . , t 1 , , » i
or Veracity. "^ Willing, in the sccond place, he must be able,
to report the truth. The first of these elements
the Honesty, — the Sincerity, — the Veracity ; the second is the
Competency of the Witness. Both are equally necessary, and if
one or other be deficient, the testimony becomes altogether null.
These constituents, likewise, do not infer each other; for it fre-
462 • LOGIC. Lect. XKXm
quently happens that where the honesty is greatest the compe-
tency is least, and Avhere the competency is greatest the honesty is
least. But when the veracity of a witness is established, there is
established also a presumption of his competency; for an honest
man will not bear evidence to a point in regard to which his recol-
lection is not 231'ecise, or to the observation of which he had not
accorded the requisite attention. In truth, when a fact depends on
the testimony of a single witness, the competency of that witness
is solely guaranteed by his honesty. In regard to the honesty of a
witness, — this, though often admitting of the highest probability,
never admits of absolute certainty ; for, though, in many cases, we
may know enough of the general character of the witness to rely
with perfect confidence on his veracity, in no case can we look into
the heart, and observe the influence which motives have actually
had upon his volitions. We are, however, compelled, in many of
the most important concerns of our existence, to depend on the
testimony, and, consequently, to confide in the sincerity, of others.
But from the moral constitution of human nature, we are war-
ranted in presuming on the honesty of a witness; and this pre-
sumption is enhanced in proportion as the following circumstances
concur in its confirmation. In the first place, a witness is to be pre-
sumed veracious in this case, in proportion as his love of truth is
already established from others. In the second place, a witness is
to be presumed veracious, in proportion as he
The presumption of jjgg fewer and weaker motives to falsify his tes-
ones y o a ' * timouv. In the third place, a witness is to be
new enhanced by cer- • '^ ' _
tain circumstances. presumed veracious, in proportion to the like-
lihood of contradiction which his testimony
would encounter, if he deviated from the truth. So much for the
Sincerity, Honesty, or Veracity of a witness.
"In regard to the Competency or Ability of a witness, — this, in
general, depends on the supposition, that he has
(b) Competency of a j^^^ j^ ^^ j^j^ ^^^,^^ COlTCCtly tO obscrve the foct
5 itness. '■ "'
to which he testifies, and correctly to report it.
The presumption in favor of the competence of a witness rises in
proportion as the following conditions are ful-
Circumstances by filled: — In thc first place, he must be pre-
^•hich the presump- ^^^^^^ competent in reference to the case in
tiou of competency js ^ , .
enhanced. hand, in proportion as his general ability^to
observe and to communicate his observation
nas been established in other cases. In the second place, the
competency of a witness must be presumed, in proportion as in
the particular case a lower and commoner amount of ability is
Lkct. XXXIII. LOGIC. , 463
requisite rightly to observe, and rightly to report the observation.
In the third place, the competency of a witness is to be presumed,
in proportion as it is not to be presumed that his observation was
made or communicated at a time when he was unable correctly to
make or correctly to communicate it. So much for the Competency
of a witness.
"Now, when both the good will and the ability, that is, when
both the Veracity and Competence of a witness
e ere i iiy jjave been sufficiently established, the credibility
Testimony not invali- j ^ j
dated because the fact of his testimony is not to be invalidated because
testified is one out of tijg fact Avhich it goes to provc is one out of
the ordinary course ^j^^ ordinary course of experience." ^ Thus it
of experience. *' '■
would be false to assert, Avith Hume, that mira-
cles, that is, suspensions of the ordinary laws of nature, are incapa-
ble of proof, because contradicted by what we have been able to
observe. " On the contrary, where the trustworthiness of a witness
or witnesses is unimpeachable, the very circumstance that the ob-
ject is one in itself unusual and marvellous, adds greater weight to
the testimony ; for this very circumstance would itself induce men
of veracity and intelligence to accord a more attentive scrutiny to
the fact, and secure from them a more accurate report' of their
observation.
" The result of what Jias now been stated in regard to the credi-
bility of Testimony in general, is : — That a tes-
Summary regarding timony is entitled to Credit when the requisite
timony^in gener*li. *"' Conditions, both on the part of the object and
on the part of the subject, have been fulfilled.
On the part of the object these are fulfilled when the object is
absolutely possible, as an object of the higher faculty of experience,
— the Understanding, — the Elaborative Faculty, and relatively
possible, as an object of the lower or subsidiary faculties of experi-
ence, — Sense, and Self-consciousness. In this case, the testimony,
qua testimony, does not contradict itself. On the part of the sub-
ject the requisite conditions are fulfilled when the trustworthiness,
that is, the veracity and competency of the witness, is beyond rea-
sonable doubt. In regard to the veracity of the witness, — this
cannot be reasonably doubted, when there is no positive ground on
which to discredit the sincerity of the witness, and when the only
ground of doubt lies in the mere general possibility of deception.
And in reference to the competency of a witness, — this is exposed
to no reasonable objection, when the ability of the witness to
observe and to communicate the fact in testimony cannot be dis-
1 Esser, Logik^ § 154. — Ed.
464
LOGIC.
Lect XXXill.
II. Testimony in
ipeeial, as Immediate
aiid Mediate.
1°, Immediate Testi-
mony.
Conditions of its
Credibility.
allowed. Having, therefore, concluded the consideration of testi-
mony in general, we proceed to treat of it in special, that is, in so
far as it is viewed either as Immediate or as Mediate." * Of these
in their order.
The special consideration of Testimony, when that testimony is
Immediate. — "An immediate testimony, or tes-
timony at first hand, is one in which the fact
reported is an object of the proper or personal
experience of the reporter. Now it is manifest,
that an immediate witness is in general better
entitled to credit than a witness at second hand ; and his testimony
rises in probability, in proportion as the requisites, already speci-
fied, both on the part of its object and on the pai't of its subject,
are fulfilled. An immediate testimony is, therefore, entitled to
credit, — 1°, In proportion to the greater ability with which the
observation has been made ; 2°, In proportion
to the less impediment in the way of the obser-
vation being perfectly accomplished ; 3", In
))roportion as what was observed could be fully and accurately
rt'membeved ; and, 4°, In proportion as the facts observed and
remembered have been communicated by intelligible and unambig-
uous signs.
"Now, whether all these conditions of ♦a higher credibility be
fulfilled in the case of any immediate testimony,
— this cannot be directly and at once ascer-
tained ; it can only be inferred, with greater or
less certainty, from the qualities of the witness ;
and, consequently, the validity of a testimony
can only be accurately estimated from a critical
knowledge of the personal character of the witness, as given in his
intellectual and moral qualities, and in the circumstances of his life,
which have concurred to modify and determine these. The verac-
ity of a witness either is, or is not, exempt from doubt ; and, in the
latter case, it may not only lie open to doubt, but even be exposed
to suspicion. If the sincerity of the witness be indubitable, a
direct testimony is always preferable to an indirect ; for a direct
testimony being made with the sole intent of establishing the cer-
tainty of tlie fact in question, the competency of the witness is less
exposed to objection. If, on the contrary, the sincerity of the wit-
ness be not beyond a doubt, and, still more, if it be actually sus-
pected, in that case an indirect testimony is of higher cogency
than a dii'ect; for the indirect testimony being given with another
Whether all these
conditions are fulfilled
in tlK! case of any im-
mediate testimony,
cannot be directly as-
certained.
1 Esser. Logik, f 154. — Ed.
Lscr. XMXIIL LOGIC. 465
view tlinn merely to establish the fact in questir>ft, the intention of
the witness to falsify the truth of the fact has not so strong a pre-
tjuinption in its favor. If both the sincerity and the compotenoy
of the witness are altogether indubitable, it is then of no impor-
tance whether the truth of the fact be vouched for by a single wit-
ness, or by a plurality of witnesses. On the other hand, if the
sincerity and competency of the witness be at all doubtful, the
credibility of a testimony will be greater, the greater the number
of the witnesses by whom the flict is corrob-
when testimony at- orated. But here it is to be considered, that
le ''g e-^ when there are a plurality of testimonies to the
gree of probability. ^ J
same fact, these testimonies are either consistent.
or inconsistent. If the testimonies be consistent, and the sincerity
and competency of all the witnesses complete, in that case the taa-
timony attains the highest degree of probability of which any testi-
mony is capable. Again, if the witnesses be inconsistent, — on this
hypothesis two cases are possible ; for either their discrepancy is
negative, or it is positive. A negative dis-
Neeative and Posi- • r •.
^ crepancy arises, where one witness passes over
tive Discrepancy. ', • . . .
in silence what another witness positively avera.
A positive discrepancy arises, where one witness explicitly affirms
something, which something another witness explicitly denic*3.
When the difference of testimonies is merely negative, we may
suppose various causes of the silence ; and, therefore, the positive
averment of one witness to a fact is not disproved by the mere cir-
cumstance that the same fact is omitted by another. But if it be
made out, that the witness who omits mention of the fact could
not have been ignorant of that fact had it taken place, and, at the
same time, that he could not have passed it over without violating
every probability of human action, — in this case, the silence of
the one witness manifestly derogates from the credibility of the
other witness, and in certain circumstances may annihilate it alto-
gether. Where, again, the difference is positive, the discrepancy
is of greater importance, because (though there are certainly excep-
tions to the rule) an overt contradiction is, in general and in itself,
of stronger cogency than a mere non-confirmation by simple silence.
Now the positive discrepancy of testimonies either admits of
conciliation, or it does not. In the former case, the credibility
of the several testimonies stands intact ; and the discrepancy
among the witnesses is to be accounted for by such circum stall ces
as explain, without invalidating, the testimony considered in itself.
In the latter case, one testimony manifestly detracts from the cred-
ibility of another; for of incompatible testimonies, while both can-
d9
466
LOGIC.
lect. xxxm.
2°, Mediate Testi
mbuy.
not be tnie, the one must be false, when reciprocally con trad ictorv,
or they may both be false, when reciprocally contrary. In this
case, the whole question resolves itself into one of ^the greater or
less trustworthiness of the opposing witnesses. Is the trustworthi-
ness of the counter-witnesses equally great ? In that case, neither
of the conflictive testimonies is to be admitted. Again, is the
trustworthiness of the witnesses not upon a par? In that case, the
testimony of the witness whose trustworthiness is the greater, ob-
tains the preference, — and this more especially if the credibility
of the other witnesses is suspected." *
So much for the Credibility of Testimony, considered in Special,
in so far as that testimony is Immediate or at First Hand ; and I
now, in the second place, pass on to consider, likewise in special,
the Credibility of Testimony, in so far as that testimony is Medi-
ate, or at Second Hand.
"A Mediate Testimony is one where the fact is an object not of
Personal, but of Foreign Experience. Touch-
ing the credibility of a mediate testimony, this
supposes that the report of the immediate, and
that the report of the mediate, witness are both trustworthy.
Whether the report of the immediate witness be trustworthy, —
this we are either of ourselves able to determine, viz., from our
personal acquaintance with his veracity and competence ; .or we are
unable of oui-selves to do this, in which case the credibility of the
i?nmediate must be taken upon the authority of the mediate wit-
ness. Here, however, it is necessary for us to be aware, that the
mediate witness is possessed of the ability requisite to estimate the
credibility of the immediate witness, and of the honesty to commu-
nicate the truth without retrenchment or falsification. But if the
trustworthiness both of the mediate and of the immediate witness
be sufficiently established, it is of no consequence, in regard to the
credibility of a testimony, whether it be at firet hand or at second.
Nay, the testimony of a mediate may even tend to confirm the tes-
timony of an immediate witness, when his own competence fiurly
to appreciate the report of the immediate witness is indubitable.
If, however, the credibility of the immediate witness be unimpeach-
able, but not so the credibility of the mediate, in that case the
mediate testimony, in respect of its authority, is inferior to the
immediate, and this in the same proportion as the credibility of
the second hand witness is inferior to that of the witness at first
hand. Further, mediate witnesses are either Proximate or Remote;
and, in both cases, either Independent or Dependent. The trust-
1 Esser, Ugik, f 166. — Ed.
Lect. XXXIII. LOGIC. 467
worthiness of proximate witnesses is, in general, greater than the
trustworthiness of remote ; and the credibility
Mediate Witnesses n • •> i ■ i i j
are either Proximate ©^ independent Witnesses greater than the cred-
or Remote, and either ibility of dependent. The remote witness is
Independent or De- unworthy of belief; when the intermediate links
^'^ ^° ■ are wanting between him and the original wit-
ness ; and the dependent witness deserves no credit, when that
on which his evidence depends is recognized as false or unestab-
lished. Mediate testimonies are, likewise, either direct or indirect;
and, likewise, when more than one, either reciprocally congruent or
conflictive. In both cases the credibility of the witnesses is to
be determined in the same manner as if the testimonies were
immediate.
" The testimony of a plurality of mediate witnesses, where there
is no recognized immediate witness, is called a
Rumor, — what. rumor. if the , witnesses be contemporaneous;
Tradition. ' ,
and a tradition^ if the witnesses be chronolog-
ically successive. These are both less entitled to credit, in propor-
tion as in either case a fiction or falsification of the fact is compara-
tively easy, and, consequently, comparatively probable." *
1 Eaeer, Logik, i 156. —Ed.
LECTUEE XXXIV.
, MODIFIED METHODOLOOY.
SECTION I.— OF THE ACQUISITION OF KNOWLEDGBL
t. EXPERIENCE. — B. FOREIGN : — RECORDED TESTIMONY
AND WRITINGS m GENERAL.
II. SPECULATION.
lir our last Lecture, we were engaged in the consideration of
Testimony, and the Principles by which its
Criticism of Re- Credibility is governed, — on the supposition
and ^ f w ^/"°"r^ always that we possess the veiitable report of
general. the witness whose testimony it professes to be,
and on the supposition that we are at no loss to
understand its meaning and purport. But questions may arise in
regard to these points, and, therefore, there is a further critical pro-
cess requisite, in order to establish the Authenticity, — the Integ-
rity, and the Signification, of the documents in which the testi-
mony is conveyed. This leads to the important subject, — the
Criticism of Recorded Testimony, and of Writings in general. T
shall comprise the heads of the following observations on this sub-
ject in the ensuing paragraph.
% ex. The examination and judgment of Writings profess-
ing to contain the testimony of certain
Par. ex. Criticism witucsscs, and of Writings in General pro-
and Interpretation. _ ' .
fessing to be the work of certain authors, \a
of two parts. FoV the inquiry regards either, 1°, The Authen-
ticity of the document, that is, whether it be, in whole or ii
part, the product of its ostensible author; for ancient writing
in particular are frequently supposititious or interpolated ; or
2°, It regards the Meaning of the words of which it is com«|
posed, for these, especially when in languages now dead,
Legt. XXXIV. LOGIC. 4^9
frequently obscure. The forrner of these problems is resolved
by the Art of Criticism (Critica), in the stricter sense of the
term ; the latter by the Art of Interjvetation {Exegetica or
Uernxeneutica). Criticism is of two kinds. If-it be occupied
with the criteria of the authenticity of a writing in its totality,
or in its principal parts, it is called the Higher^ and sometimes
the Interlude Criticism. If, again, it consider only the integ-
rity of particular words and phrases, it is called the Low^^
and sometimes the External, Criticism. The former of thes^
may perhaps be best styled the Criticism, of Authenticity j — -
the latter, the Criticism of Integrity.
The problem which Interpretation has to solve is, — To
discover and expound the meaning of a writer, from the
words in which his thoughts are expressed. It departs from
the principle, that however manifold be the possible meanings
of the expressions, the sense of the writer is one. Interpreta-
tion, by reference to its fsoui'ces or subsidia, has been divided
into the Gramrriaticaly the Historical, and the Philosophical,
Exegesis}
"Testimonies, especially when the ostensible witnesses themselves
can no longer be interrosrated, may be subiected
Explication. '^ . . ° . *^ „ "^ '
to an examination under various lorms ; ana
this examination is in fact indispensable, seeing not only that a
false testimony may be subiftituted for a true, and a testimony true
upon the whole may yet be falsified in its parts, — a practice which,
prevailed to a great extent in ancient times ; while at the same
time the meaning of the testimony, by reason either of the foreign
character of the language in which it is expressed, or of the foreign
character of thought in which it is conceived, may be obscure and
undetermined. The examination of a testimony is twofold, inag*
much as it is either an examination of its Au-
•The examination of ^ . . . ■ „
a te^tiraouy twofold, thenticity and Integrity, or an examination of
— of its Autiieiiticity its Meaning. This twofold process of examina-
atid Integrity, and of ^Jqjj jg applicable to testimonies of every kind,
but it becomes indispensable when the testi-
mony has been recorded in writing, and when this, from its anti-
qiiity, has come down to us only in transcripts, indefinitely removed
fropi the original, and when the witnesses are men differing greatly
from ourselves in language, niaimers, customs, and associations of
} Qt Krug, Lagifc, * 177 «t seg. ^ Eo. {gn*ll, IfOgH;, P- »• ♦ 6 p. 196. Kiesewetter.I^gi'^ P
ii. } 185 et seq.]
470
LOGIC.
Lect. XXXIV.
Criticism.
Its problems.
thought. The solution of the problem, — By what laws are the
authenticity or spuriousness, the integrity or
corruption, of a writing to be determined, —
constitutes the Art of Criticism, in its stricter signification [Crit-
ica) ; and the solution of the problem, — By what law is the sense
or meaning of writing to be determined, — con-
interpretation. . ° ^ ^,® . _,..
stitutes the Art oi Interpretation or Exposition
{ITermeneuticayExegetica). In theory, Criticism ought to precede
Interpretation, for the question, — Who has spoken, naturally arises
before the question, — How what has been spoken is to be under-
stood. But in practice, criticism and interpretation cannot be sepa-
rated ; for in application they proceed hand in hand." *
" First, then, of Criticism ; and the question that presents itself iii
the threshold is, — What are its Definition and
I. Criticism. t>.- • • o xt t y-. • • • • i i
Divisions/ Under Criticism is to be under-
stood the complement of logical rules, by which the authenticity or
spuriousness, the integrity or interpolation, of a writing is to be
judged. The problems which it proposes to
answer are — 1°, Does a writing really proceed
from the author to whom it is ascribed ; and, 2°, Is a writing, as we
possess it, in all its parts the same as it came from the hands of its
author. The system of fundamental rules, which are supposed in
judging of the authenticity and integrity of every writing, consti-
tutes what is called the Doctrine of Universal
Criticism; and the system of particular rules,
by which the authenticity and integrity of writings of a certain
kind are judged, constitutes the doctrine of what is called Special
Criticism. It is manifest, from the nature of
Logic, that the doctrine of Universal Criticism
is alone within its sphere. Now Universal
Criticism is conversant either with the authen-
ticity or spuriousness of a writing coiJsider»'<l a.s
a whole, or with the integrity or interpolation of certain parts. In
the foimer case it is called Higlier^ in the latter,
Lower^ Criticism ; but these denominations are
inappropriate. The one criticism has also been styled the Internaly
the other the External; but these appellations are, likewise, excep-
tionable ; and, perhaps, it would be preferable to call the form6^
the Criticism, of the Authenticity, the latter, the Criticism of th^
Integrity, of a work. I shall consider these in particular; and, first,
of the Criticism of Authenticity.
.'.'A proof of the authenticity of a writing, more especially of an
Universal Criticism.
Bpecial Criticism.
Universal Criticism
alone within the
sphere of Logic.
Its Divisions.
1 EaMf, Logik, § 157. — Ed.
Lkct. XXXIV. LOGIC. 471
ancient writing, can be rested only upon two grounds, — an Intev'-
nal and an External, — and on these either
1. Criticism of Au- . • t • ^- -o • ^ 7 7
apart or in combination. By internal qrounds.
fbenticity. ^ . . ^ . . . ,
we mean those indications of authenticity which
the writing itself affords. By external grounds^ we denote the tes-
timony borne by other works, of a corresponding antiquity, to the
authenticity of the writing in question.
" In regard to the Internal Grounds ; — it is evident, without
entering upon details, that these cannot of
(a) Internal Grounds.
These of themselves theiiiselves, that IS, apart from the external
not sufficient to cstab- grounds, afford evidence capable of establish-
lish the authenticity j^g beyoud a doubt the authenticity of an an-
of a writing. . , . . „ ., ' ^\ ..
cient writing; lor we can easily conceive that
an able and learned forger may accommodate his fabrications both
to all the general circumstances of time, place, pecjple, and lan-
guage, under which it is supposed to have been written, and even
to all the particular circumstances of the style, habit of thought,
personal relations, etc., of the author by whom it professes to have
been written, so that everything may militate for, and nothing mili-
tate :igainst, its authenticity.
" But if our criticism from the internal grounds alone be, on the
one hand, impotent to establish, it is, on the
u omnipo en o other, omnipotent to disprove. For it is suffi-
disprove thi.s. _ ' ' ....
cient to show that a writing is in essential parts,
that is, parts which cannot be separated from the whole, in opposi-
tion to the known manners, institutions, usages, etc., of that people
with which it would, and must, have been in harmony, were it the
product of the writer whose name it bears ; that, on the contrary,
it bears upon its face indications of another country or of a later
age ; and, finally, that it is at variance with the personal circum-
stances, the turn of mind, and the pitch of intellect, of its pre-
tended author. And here it is to be noticed, that these grounds
are only relatively internal ; for we become aware of them origi-
nally only through the testimony of others, that is, through exter-
nal grounds."*
In regard to the External Grounds ; — they, as I said, consist
in the testimony, direct or indirect, given to
(b) External Grounds. • , , .... . . . . ,
the authenticity or the writing in question by
other works of a competent antiquity. This testimony may bo
contained either in other and admitted writings of the supposed
author himself; or in those of contemporary writers ; or in those
of writers approximating in antiquity. This testimony may also be
1 Esser, Log^i't, S 158—160. — Ed.
472 LOGIC. Lect. XXXIV.
given either directly, by attribution of the disputed writing by
title to the author ; or indirectly, by quoting as his certain pas-
sages which are to be found in it. On this subject it is needless to
go into detail, and it is hardly necessary to observe, that the proof
of the authenticity is most complete when it proceeds upon the
internal and external grounds together. I, therefore, pass on to
the Criticism of Integrity.^
" When the authenticity of an ancient work has been established
on external grounds, and been confirmed on
X. t-"tic»sm o n- internal, the integrity of this writing is not
therewith proved ; for it is very ])ossible, and
in ancient writings indeed very probable, that particular passages
are either interpolated or corrupted. The authenticity of particu-
lar passages is to be judged of precisely by the same laws which
regulate our criticism of the authenticity of the whole work. The
proof most pertinent to the authenticity of particular passages is
drawn — "1°, From their acknowledgment by the author himself in
other, and these unsuspected, works ; 2°, From the attribution of
them to the author by other writers of competent information ;
and, 3°, From the evidence of the most ancient MSS. On the
other hand, a passage is to be obelized as spurious, — 1°, When
found to be repugnant to the general relations of time and place,
and to the personal relations of the author ; 2", When wanting in
the more ancient codices, and extant only in the more modern.
A passage is suspicious, when any motive for its interpolation is
manifest, even should we be unable to establish it as spurious.
The differences which different copies of a writing exhibit in the
particular passages, are called various readings (varicB lectiones or
lectiones variantes). Now, as of various readings only one can be
the true, while they may all very easily be false, the problem which
the criticism of Integrity proposes to solve is, — How is the genu-
ine reading to be made out; and herein consists what is tech-
nically called the Recension^ more properly the Emendation^ of the
text.
"The Emendation of an ancient author may be of two kinds;
the one of which may be called Historical, the
Emendation of the other the Conjectural. The former of these
\ '~^,°. ^"i '" 1' founds upon historical data for its proof; the
vj?,, Historical anji » ' '
coiijccfuiai. latter, again, proceeds on grounds which lie
beyond the sphere of historical fiict, and this
fbr the very reason that histoncnl fact is found incompetent to tho
ivfttoration of the text to its original integrity, The historical
1 See Esser, Logik, {(161, 162. — Eo.
Lect. XXXIV. LOGIC. 473
emendation necessarily precedes the conjectural, because the object
itself of emendation is wholly of an historical character, and be-
cause it is not permitted to attempt any other than an emendation
on historical grounds, until, from these very grounds themselves, it
be shown that the restitution of the text to its original integrity
cannot be historfcally accomplished. Historical
Historical Emenda- Emendation is again of two kinds, according as
tion of two kiuds,— j|.g judgment proceeds on external or on inter-
External . and Inter- , i t^ /> i .1 1
nal grounds. It founds upon external grounds,
when the reasons for the truth or falsehood of
a reading are derived from testimony ; it founds upon internal
grounds, when the reasons for the truth or falsehood of a reading
are derived from the writing itself. Historical emendation has thus
a twofold function to perform (and in its application to practice,
these must always be performed in conjunction), viz., it has care-
fully to seek out and accurately to weigh both the external and
internal reasons in support of the reading in dispute. Of external
grounds the principal consists in the confirmation afforded by MSS.,
by printed editions which have immediately emanated from MSS.,
by ancient translations, and by passages quoted in ancient authors.
The internal grounds are all derived either from the form, or from
the contents, of the. work itself. In reference to the form, — a
reading is probable, in proportion as it corresponds to the general
character of the language prevalent at the epoch when the work
was written, and to the peculiar character of the language by which
the author himself was distinguished. In reference to the contents,
— a reading is probable, when it harmonizes with the context, that
is, when it concurs with the other words of the particular passage in
which it stands, in affording a meaning reasonable in itself, and con-
formable with the author's oj^inions, reasonings, and general charac-
ter of thought." ^
" It frequently happens, however, that, notwithstanding the uni-
formity of MSS., and other external subsidia, a
conjectura Emen- reading cannot be recognized as genuine. In
datioQ. ® 00
this case, it must be scientifically shown from
the rules of criticism itself that this lection is corrupt. If the
demonstration thus attempted be satisfactory, and if all external
subsidia have been tried in vain, the critic is permitted to con-
sider in what manner the corrupted passage can be restored to
its integrity. And here the conjectural or divinatory emenda-
tion comes into play ; a puocess in which the power and effi-
J Esser, Logik. § 1G3. -Ed.
GO
474
LOGIC.
Lect. XXXIV.
II. Interpretation.
General and Special.
ciency of criticism and the genius of the critic are principally
manifested." ^
So much for Criticism, in its applications both to the Authen-
ticity and to the Integrity of Writings. We have now to consider
the general rules by which Interpretation, that is, the scientific pro-
cess of expounding the Meaning of an author, is regulated.
"By the Art of Interpj'etation, called likewise technically JTer-
meneutic or JEJxegetic, is meant the complement
of logical laws, by which the sense of an ancient
writing is to be evolved. Hermeneutic is either General or Spe-
cial. General, when it contains those laws
which ajDply to the interpretation of any writ-
ing whatever; Special, when it comprises those laws by which
writings of a particular kind are to be expounded. •The former
of these alone is of logical concernment. The problem proposed
for the Art of Interpretation to solve, is, — How are we to proceed
in order to discover from the words of a writing that sole meaning
which the author intended them to convey ? In the interpretation
of a work, it is not, therefore, enough to show in what signification
its words may be underetood ; for it is required that we show in
what signification they must. To the execution of this task two
conditions are absolutely necessary ; 1°, That the interpreter should
be thoroughly acquainted with the language itself in general, and
with the language of the writer in particular ; and, 2°, That the
interpreter should be familiar with the subjects of which the writing
treats. But these two requisites, though indispensable, are not of
themselves suflicient. It is also of importance that the expositor
should liave a competent acquaintance with the author's personal
circumstances and character of thought, and with the history and
spirit of the age and country in which he lived. In regard to the
intei"pretation itself, — it is to be again observed, that as a writer
could employ expressions only in a single sense, so the result of the
exposition ought to be not merely to show what meaning may pos-"
sibly attach to the doubtful terms, but what meaning necessarily
must. When, therefore, it appears that a passage is of doubtful
import, the best preparative for a final determination of its mean-
ing is, in the first place, to ascertain in how many diflferent significa-
tions it may be construed, and then, by a process of exclusion, to
arrive at the one veritable meaning. When, however, the obscu-
rity cannot be removed, in that case it is the duty of the expositor,
1 F^sser, LosH', i 10(>- — 1^- [Pan/iasiana, i. 859—365, 2d ed. 1701. Gcnuensis, Ars Ijogico-
Cfitica, L. iv. C. vi. ft srq.]
Lect. XXXIV. LOGIC. 475
before abandoning his task, to evince that an interpretation of
the passage is, without change, absolutely or relatively impossible.
"As to the sources from whence the Interpretation is to be
drawn, — these are three in all, — viz., 1°, The
ourceso n rpre- Tractus lUerarum. the words themselves, as
tation. ' '
they appear in MSS. ; 2°, The context, that is,
the passage in immediate connection with the doubtful term ; 3°,
Parallel or analogous passages in the same, or in other writings." ^
How the interpretation drawn from these sources is to be applied, I
shall not attempt to detail ; but pass on to a more generally useful
and interesting subject.
So much for Experience or Observation, the first mean of
scientific discovery, that, viz., by which we
Specaiation the Sec- apprehend what is presented as contingent
ond Means of Knowl- , -t ^ ■, n x t
gjj phaenomena, and by whose process oi Induc-
tion and Analogy we cany up individual into
general facts. We have now to consider the other mean of sci-
entific discovery, that, viz., by which, from the j^haenomena pre-
sented as contingent, we separate what is really necessary, and
thus attain to the knowledge, not of merely generalized facts,
but of univei-sal laws. This mean may, for distinction's s.ike,
be called Speculation^ and its general nature I comprehend in the
following i^aragraph.
^ CXI. When the mind does not rest contented with
observing and classifying the objects of
Par. CXI. Specula- j^g experience, but, by a reflective analy-
tion, — as a means °^ . -, , , , ■»
' Knowledge. SIS, suudci's the concrctc wholes presented
to its cognition, throws out of account
all that, as contingent, it can think away from, and con-
centrates its attention exclusively on those elements which,
as necessary conditions of its own acts, it cannot but think ;
— by this process it obtains the knowledge of a certain
order of facts, — facts of Self-consciousness, which, as essen-
tial to all Experience, are not the result of any ; consti-
tuting in truth the Laws by which the possibility of our
cognitive functions is determined. This process, by which
we thus attain to a discriminative knowledge of the N'eces-
aary^ Native, and, as they are also called, the Noetic, Pure,
a priori, or Transcendental, Elements 'of Thought, may be
styled Speculative Analysis, Analytic Speculation, or Specu-
1 Esser, Logik, i 167. — Ed. [Cf. Snell, Logik, p. ii. i 6, p. 200.]
476 LOGIC, Lect. XXXIV.
lation simply, and is carefully to be distinguished from Inducr
tion, with which it is not unusually confounded.
** The em{>irical knowledge of which we have hitherto been,
speaking, does not, however varied and exten-
Kxplicatioii. , . , „, • /> i i • i •
give It naay be, suffice to satisfy the thinking
niind as such ; for our empirical knowledge itself points at certain
higljer cognitions from which it may obtain completion, and which
me of a very different character from that by which the mere em-
pirical cognitions themselves are distinguished. The cognitions are
styled, among other names, by those of noetic^ pure, or rational,
and they are such ns cannot, though manifested in experience,
be derived from experience; for, as the conditions under which
experience is possible, they must be viewed as necessarj' con-
stituents of the nature of the thinking principle itself. Philos-
ophers have indeed been found to deny the reality of such cog-
nitions native to the mind ; and to confine the whole sphere
of human knowledge to the limits of experience. But in this
c.ise philosophers have overlooked the important circumstance,
that the acts, that is, the apprehension and judgment, of expe-
rience, ;;ro themselves impossible, except under the supposition
of cert:;|n potential cognitions previously existent in the think-
.ng subject, and. which become actual on occasiop of an object
being piesented to the external or internal sense. As an exam-
ple of a poetic cognition, the following propositions may suf-
fice:.-^ An object and all its attributes are convertible; — All
that is has its sufficient cause. The principal distinctions of
Empirical and Rational Knowledges, or rather
I'rincipai distinc- Empirical and Noetic Cognitions, are the fol-
fions of Empirical i • -lo x? • • i •*• • • ^
Noetic c lowing : — 1 , Empirical cognitions originate
jiong. exclusively in experience, whereas noetic cog-
nitions are virtually at least before or above
all experience, — all experience being only possible through them.
'Z°, Empirical cognitions come piecemeal and successively into exist-
cM^p, (jnd may again gradually fade and disappear; whereas noetic
cognitions, like Pallas, armed and immortal from the head of Jupi-
ter, spring at once into existence, complete and indestructible. 3°,
P^mpirical cognitions find only an application to those objects from
which they were originally abstracted, and, according a» things
obtain a different form, they also may become differently fash-
ioned ; noetic cognitions, on the contrary, bear the character im-
pressed on them of necessity, universality, sameness. Whether
a cognition be t'Uipirical or noetic, can only be determined by
Lect. XXXIV.
LOGIC.
477
P
considering whether it can or cannot be presented in a sensible
perception ; — whether it do or do not stand forward clear, dis-
tinct, and indestructible, bearing the stamp of necessity and abso-
lute universality. The noetic cognitions can be detected only by a
critical analysis of the mental phenomena proposed for the purpose
of their discovery;"^ and this analysis may, as I have said, be
styled Speculation, for want of a more appropriate appellation.
1 Esser, Logik, f 171. — Ed.
LECTURE XXXV.
MODIFIED METHODOLOOY.
SECTION I. — OF THE ACQUISITION OF KNOWLEDGE
III. COMMUNICATION OF KNOWLEDGE. — A. INSTRUCTION
— ORAL AND WRITTEN. — B. CONFERENCE —
DIALOGUE AND DISPUTATION.
I NOW go on to the last Mean of Acquiring and Perfecting our
knowledge ; and commence with the following paragraph :
^ CXII. An important mean for the Acquisition and Per-
fecting of Knowledge is the Communica-
tion of Thought. Considered in general,
the Communication of thought is either
One-sided, or Mutual. The former is called
Instruction (mstitutio), the latter, Confer-
ence (coHocutio) ; but these, though in theory distinct, are in
practice easily combined. Instruction is again either Oral or
Written; and Conference, as it is interlocutory and familiar, or
controversial and solemn, may be divided into Dialogue (col-
loqimim^ dialoffus), and Disjmtation (disputatio, concertatid).
The Corninunication of thought in all its forms is a means of
intellectual imj)rovement, not only to him who receives, but to
him who bestows, information ; in both relations, therefore, it
ought to be considered, and not, as is usually done, in the
former only.^
Par. CXII. The
Communication of
Thought, — as a m eans
of Acquiring and Per-
fecting Knowledge.
In illustrating this paragraph, I shall commence with the last
sentence, and, before treating in detail of In-
Explication. • i ^ /. /. i
struction and Conference, as means ot extend-
ing the limits of our knowledge by new acquisitions derived from
1 Cf. Krug, Logik, s 181 e« je?.— Ed
Lect. XXXV.
LOGIC.
479
The Communication
of Thought an impor-
tant mean towards the
perfecting of Knowl-
edge in the mind of
the communicator.
the communication of others, I shall endeavor to show, that the
Communication of thought is itself an impor-
tant mean towards the perfecting of knowledge
in the mind of the communicator himself. In
this view, the communication of knowledge is
like the attribute of mercy, twice blessed, —
" blessed to him that gives and to him that
takes;" in teaching others we in tact teach ourselves.
This view of the reflex eifect of the communication of thought
on the mind, Avhether under the form of Instruction or of Confer-
ence, is one of high importance, but it is one which has, in modern
times, unfortunately been almost wholly overlooked. To illustrate
it in all its bearings would require a volume ; at present I can
only contribute a few hints towards its exposition.
Man is, by an original'tendency of his nature, determined to com-
municate to others what occupies his thoughts,
and by this communication he obtains a clearer
understanding of the subject of his cogitations
than he could otherwise have compassed. This
fact did not escape the acuteness of Plato. In
the Protagoras, — " It has been well," says
Plato (and he has sundry passages to the point), — "It has been
well, I think, observed by Homer —
Man naturally de-
termined to communi-
cation.
This fact noticed by
Plato.
' Through mutual intercourse and mutual aid,
Great deeds arc done and great discoveries made;
The wise new wisdom on the wise bestow,
Whilst the lone thinlvcr's thoughts come slight and slow.'l
For in company we, all of us, are more alert, in deed and word
and thought. And if a man excogitate aught by himself, forthwith
he goes about to find some one to whom he may reveal it, and from,
whom he may obtain encouragement, aye and until his discovery be
completed."^ The same doctrine is maintained
by Aristotle, and illustrated by the same quota-
tion ; ^ (to which, indeed, is to be referred the
adage, — "Unus homo, nullus homo.") — "We
rejoice," says Themistius, "in hunting truth in
company, as in hunting game."* Lucilius, —
"Scire est nescire, nisi id me scire alius scierit;* — paraphrased in
Aristotle.
Themistius.
Lucilius.
1 Altered from Pope's Homer, Book x. 266.
2 Protag., p 348. Compare Lectures on Met-
aphysics, p. 261.
8 Etk. Nie., viil. 1.
4 Orat.,xxi. Erplorator aut Philosophus, Ora-
tiones, p. 254, ed. Harduin, Paris, 1684. — Ed.
5 Fragm., 25, in the Bipont edition of Per-
sius and Juvenal, p. 176. — Ej>.
4B0
LOGIC.
LiXT. XXXV.
the compacter, though far inferior, verse of Peisius, — " Scire tuum
nihil est, nisi te scire hoc sciat alter."' — Cicero's
persins. Cato testiiRes to the same truth : — " Non facile
Cicero. cst invenire, qui quod sciat ipse, non trad;it
Seneca. alteri." ^ And Seneca : — " Sic cum hac excep-
tione detur sapientia, ut illam inclusam teneam
nee enunciem, rejiciam. Nullius boni, sine socio, jucunda possessio
est."«
" Condita tabescit, vulgata scientia cre8eit."4
Modes in which
Communication is
conducive to the Ter-
fecting of Thought
are two.
" In hoc gaudeo aliquid discere, ut doceam : nee me ulla res deleo-
tabit, licet eximia sit et salutaris, quam mihi uni, sciturus sim."*
"Ita non solum ad discendum propensi suraus, verum etiam ad
docendum." '^
The modes in which the Communication of thought is conducive
to the perfecting of thought itself, are two ; for
the mind may be determined to more exalted
energy by the sympathy of society, and by the
stimulus of opposition ; or it may be necessi-
tated to more distinct, accurate, and orderly
thinking, as this is the condition of distinct, accurate, and orderly
communication. Of these the former requires the presence of
otliers during the act of thought, and is, therefore, only manifested
in oral instruction or in conference ; whereas the latter is operative
both in our oral and in our Written communications. Of these in
their t)rder.
In the first place, then, the influence of man on man in recipro-
cally determining a higher energy of the facul-
ties, is a phaenomenon sufficiently manifest. By
nature a social being, man has powers which
are relative to, and, consequently, find their de-
velopment in, the company of his fellows ; and
this is more particularly shown in the energies
of the cognitive faculties. "As iron sharpeneth iron," says Solo-
mon, "so a man sharpeneth the understanding of his friend.""
This, as I have said, is effected both by fellow-feeling and by oppo-
sition. We see the efiects of fellow-feeling in the necessity of an
1. By reciprocally
determining a higher
energy of the facul-
ties.
(a) Through Sympa-
thy.
II. 27. — Ed.
S Cato apud Cicero, De Fin., iii. c. 20, (
66.
* Seiioca, JE/7., vi.
* Quoted al80 in Dismssions. p. 778 This
line nppearg to have been taken from a ntnall
volume entitled Carminum Proverbiaiium Loti
Communes, p. 17, Lond. 1583; but the author
is not named. — Ed.
fi Seneca, Epift., vi. — Ed.
6 Cicero, De Fin., iii. 20. — Ed.
7 Proverbf, xxvii. 17. The authorized ver-
sion is, countenance of his friend. CompM*
Lectures on Mttaphysics, p. 261. — ED.
L:;CT. ::XXV. LOGIC. 481
aadicuce to cull forth the exertions of the orator. Eloquence
requires numbers ; and oratory has only flourished where the con-
dition of large audiences has been supplied.
. '""^ opposi- g^^^ opposition is perhaps still more powerful
than mere sympathy in calling out the re-
sources of the intellect.
In the mental as well as in the material world, action and i-eac-
tion are ever equal ; and Plutarch ^ well ob-
Plutarch. , ^ .'
seiTCS, that as motion would cense were con-
tention to be taken out of the physical universe, so progress in
improvement would cease were contention taken out of the moral ;
•troXjifWi dirdvTwv TraTrjp?
"It is maintained," says the subtle Scaliger, " by Vives, that we
profit more by silent meditation than by dis-
Scaliger, J. C • , mi • • , -ry r- • ^• • -,■
pute. 1 his IS not true, bor as fare is elicited
by the collision of stones, so truth is elicited by the cpllision of
minds. I myself (he adds) frequently meditate by myself long
and intently ; but in vain ; unless I find an antagonist, there is no
hope of^ a saccessful issae. By a master we are more excited than
by a book; but an antagonist, whether by his pertinacity or his mis-
dom, is to me a double master."'
But, in the second place, the necessity of communicating a piece-
of knowledge to others, iinijoses upon us the
%. By imposing tl.e % / u* • • V 11 • C
necessity of obtaining necessity ot obtaining a fuller consciousness of
a fiiiJer coiisciousjiess that knowledge for oureelves. BThis result is to
of knowledge for qui:- ^ certain extent secured by the very process of
clothing our cogitations in words. For speech
is an analytic process; and to express our thoughts in language, it
is requisite to evolve them from the implicit into the explicit, from
the confused into the distinct, in order to bestow on each part of
the organic totality of a thought its precise and appropriate sym-
bol. But to do this is in fact only to accomplish the first step
towards the perfecting of our cognitions or thoughts.
But the communication of thought, in its higher applications,,
iaiposes on us far more than this ; and in so doing it reacts with a
»tiM more beneficial influence on our habits of thinking. Suppose
Ihat we are not merely to express our thoughts as they spontane-
«>u&ly arise; suppose that we are not merely extemporaneously to
speak, but deliberately to write, and that what we are to communi-
IVita AgesMai, Opera^ 1599, vol. i. p. 598.— Ed. 3 Exercit., f. 420. [For a criticism of Seal-
2 Heraclitus. Cf Tiiitarch, De Is.et Osir.,p. iger's remark as regards Vires, see DiscuS'
870. Brandis, Gesch. der Philo*., i. p. 1^8. —El), sions, p. 773. — Ed.]
61
482
LOGIC.
Lect. XXXV.
Influence of Compo-
sition and Instruction
in perfecting our
Knowledge.
Godwin quoted.
cate is not a simple and easy, but a complex and difficult, matter.
In this case, no man will ever fully understand
his subject who has not studied it with the view
of communication, while the power of commu-
nicating a subject is the only competent crite-
rion of his fully understanding it. "When a
man," says Godwin, " writes a book of method-
ical investigation, he does not write because he
undei-stands the subject, but he understands the subject because he
has written. He was an uninstructed tyro, exposed to a thousand
foolish and miserable mistakes, when he began his work, compared
with the degree of piofieiency to which he has attained when he
has finished it. He who is now an eminent philosopher, or a sub-
lime poet, was formerly neither the one nor the other. Many a
man has been overtaken by a premature death, and left nothing
behind him but compositions worthy of ridicule and contempt,
who, if he had lived, would perhaps have risen to the highest lite^
rary eminence. If we could examine the school exercises of men
who have afterwards done honor to mankind, we should often find
them inferior to those of their ordinary competitors. If we could
dive into the portfolios of their early youth, we should meet with
abundant matter for laughter at their senseless incongruities, and
for contemptuous astonishment." ^
" The one exclusive sign," says Aristotle,
"that a man is thoroughly cognizant of any-v
thing, is that he is able to teach it ; " ^ and Ovid,^ —
Aristotle.
' Quodqae parum novit nemo docere potest."
In this reiictive effect of the communication of knowledge in
determining the perfection of the knowledge communicated, origi-
nated the scholastic maxim Doce ut discas, — a maxim which has
unfortunately been too much overlooked in the schemes of modern
education. In former ages, teach that you may learn always con-
stituted one at least of the great means of intel-
lectual cultivation. "To teach," says Plato, "is
the way for a man to learn most and best."*
"Homines dum docent discunt," says Seneca.* "In teaching," says
riato.
Seneca.
1 Enquirer, part i. Essay iv. pp. 23, 24, ed. S Tristia, ii. 348. -
1797. — Ed. 4 rseudo-l'lnto,
2 Metaphyi., i. 1. Quoted in Discussions, p. Ed.
765. — Ed. « Epist., 7. — Ed.
Ed.
Epinomis, p.
Lect. XXXV.
LOGIC.
483
Clement of Alexandria,^ " the instructor often learns more than his
pupils." " Disce sed a doctis ; indoctos ipse
doceto," is the precept of Dionysius Cato ; ^
and the two following were maxims of au-
thority in the discipline of the middle ages.
Clement of Alexan
dria.
Dionysius Cato.
The first
The second
" Multa rogare, rogata tencre, retenta docere,
Haec tria, discipuium faciunt superare magistrum." 8
"Discere si quaeris doceas; sic ipse doceris;
Nam studio tali tibi profids atque sodali." *
Vive8.
This truth is also well enforced by the great Vives. "Doctrina est
traditio corum quae quis novit ei qui non novit.
DLsciplina est illius traditionis acceptio ; nisi
quod mens accipientis impletur, dantis vero non exhauritur, — imo
coramunicatione augetur.eruditio, sicut ignis, motu atque agitatione.
Excitatur enim ingenium, et discurrit per ea quae ad praesens nego-
tiuin jsertinent : ita invenit atque excudit multa, et quae in mentera
non veniebant cessanti, docenti, aut disserenti oecurrunt, calore
acuente vigorem ingenii. Idcirco, nihil est ad magnam eruditio-
nem perinde conducens, ut docere."' The celebrated logician, Dr.
Robert Sanderson, used to say: "I learn much
from my master, more from my equals, and most
of all from my disciples."*
But I have occupied perhaps too much time on the influence of
the communication of knowledge on those by
whom it is made ; and shall now pass on to the
consideration of its influence on those to whom
it is addressed. And in treating of communica-
tion in this respect, I shall, in the first place,
consider it as One-sided, and, in the second, as Reciprocal or
Bilateral.
The Unilateral Communication of knowledge, or Instruction, is
of two kinds, for it is either Oral or Written ; but as both these
Sanderson.
Influence of the
communication of
Knowledge on those
to whom it is ad-
dressed.
1 Stromata, lib. i. p. 275, edition Sjih.,
&ki5i<TKwv Tis fiav&dvfi ■ir\e7oy, Ka\ \eyuy
vvvoKpoarai iroAXiKis rois iiraKoiovtnv av-
rov, — Ed.
2IV. 29. — Ed.
8 [Crenius, p. 581.] [ Gabridis Naudai Syn-
tagma de Studio Liberali. Included in the
Consilia et Methodi Aureee studiorum optime
autituendorum, collected by Th. Crenius, Bot-
terdam, 1692. The lines are quoted as from
an anonymous author. — Ed.]
-* <jiven without author's name in the Car-
minum Proverbialum Loci Communes, Lond.
1683, p. 17. See above, p. 480, note *. — Ed.
5 De Anima, p. 89.
6 [Reason and Judgment, or Special Remarks
of the Life of the Renowned Dr. Sanderson, p. lO-
London: 1663.]
484 LOGIC. Lect XXXV.
species of instruction propose the same end, they are both, to a cer-
tain extent, subject to the same laws.
1. instructioD,- Oral and Written Instruction have cach their
Oral and Written.
peculiar advantages.
In the first place, instruction by the living voice has this advan-
tage over that of books, that, as more natural.
Oral instruction, — . . . • tt • ^i ^
., ^ , it IS more impressive. Hearing rouses the at-
its advantages. _ * _ _ °
(a) More natural, tcution and keeps it alive far more effectually
therefore more im- than reading. To this we have the testimony
pressive. ^^ ^^^ niost competent observers. "Hearing,"
Theophrastus. i • /.
says Theophrastus,^ "is of all the senses the
most pathetic," that is, it is the sense most intimately associate4
with sentiment and passion. "Multo magis," says the younger
Pliny, "multo magis viva vox afficit. Nam,
' licet acriora sunt quae legas, altius taraeu in
animo sedent quae pronuntiatio, vultus, habitus, gestu^ etlam dicen-
tisadfigit."2
" Plus prodest," says Valerius Maximus, " docentem atidirey quam
in librls studere ; quia vehementior fit impressio
Valerias M aximns. . . , ^ . . ....
in mentibus audientium, ex visu doctoris et
audita, quara ex studio et libro." '
And St. Jerome — "Habet nescio quid latentis energiae viva vox;
et in aures discipuli de doctoris ore transfusa,
8t Jerome. n ^- ^nt.
fortius sonat. *
A second reason why our Attention (and Memory is always in
the ratio of Attention) to things spoken is
(b) Less permanent, greater than to things read, is that what is
therefore more at- .^^ i
. , written we regard as a permanent possession
to which we can always recur at pleasure ;
whereas we are conscious that the "winged words" are lost to us
forever, if we do not catch them as they fly. As Pliny hath it :
" Legendi semper est occasio ; audiendi non semper." ^
A third cause of the superior efficacy of oral instruction is that
man is a social animal. He is thus naturally disposed to find pleas-
ure in society, and in the performance of the actions performed by
those with whom he consorts. But reading is a solitary, hearing is
^ Qjw tan iaifim 8* o2)uai (r« vpovoKQvaai fat the JF^^ of Tboinas Hijtienuco?, as4 jn
wtp\ Tijs itKovirriKris, aiV^<r*a.s, ^u 6 et6- ^^^ Anthologia of Langius, under the article
. , _ .. Doetrina. It is not, however, to be found in
I: , I r / ijjjjt a^tho^■ — Ed-J
Plutarch, De Audilione, sub intt. — Ed.
« Ernst., ii. 8 — Ed. * Epist., oiii. Optm, Antt 1679, torn. Hi p
3 [Thom«8 HiberuicuB^ p. 330.] [The above ^37. — Ed.
passage is quoted as from Valerius, lib. viii., < fyist. ii. 3. — Ed
LfeCT. XXXV. LOGIC. 48S
a«t<ydal act. In reading, we are not d^ermiw6fd to attend by any*
fellow-feeling with oth'^rs attending; whereas
(c) earing a socia -^ hearing, our attention is not only engaged by
our sympathy with the speaker, but by our sym-
pathy with the other attentive auditors around us.
Suoh are the causes which contnir in rendering Oral Instruction
more effectual than Written. "M. Varillas,"
^ ' says Menage (and Vaiillas was one of the most
learned of modern historians, — and Menage one of the most
learned of modern scholars), " M. Varillas himself told me one
day, that of every ten things he knew, he had learned nine of them
in conversation. I myself might say nearly the same thing." ^
On the other hand, Reading, though only a substitute for Oral
Instruction, has likewise advantages peculiar to
Reading, - its ad- -^g^if. j^ ^j^g gj.g^ |g^g^ j^ j^ ^^^^.^ ^j^^-j '^^^
vantages. .1 -i t i t • •
(a) More easily ac- cessible. In the second, it IS more comprehen-
c(Bssib)e. sive in its sphere of operation. In the third, it
(b) More compre- jg j^^^ transitory with the voice, but may again
, , .,* . and again be taken up and considered, so that
(c) More permanent. » _ " '
the object of the instruction may thus more
fully be examined and brought to proof. It is thus manifest, that
oral and written instruction severally supply and sevei-ally support
each other; and that, where this is competent, they ought always
to be employed in conjunction. Oral instruction is, however, in
the earlier stages of education, of principal importance ; and writ-
ten ought, therefore, at first only to be brought in as a subsidiary.
A neglect Of the oral instruction, and an exclusive employment of
the written, — the way in which those who are self-taught (the
atitodidacti) obtain their education, — for the most part betrays its
One-sided influence by a contracted cultivation of the intellect,
with a deficiency in the power of communicating knowledge to
others.
Oral instruction nece«sarily supposes a speaker and a hearer; and
written instruction a writer and a reader. In these, the capacity
of the speaker and of the writer must equally fulfil certain common
requisites. In the first place, they should be fully masters of the
subject with which their instruction is conversant ; and in the sec-
ond, they should be able and willing to communicate to Others the
knowledge which they themselves possess. But in reference to
these several Jspecies of instruction, there are various special rul-s
that ought to be attended to by those who would reap the advan-
tages they sfevierally afford. I shall commence with Written Irt-
1 Menagiana, torn. ir. p. Ill, ed. 1715. — Ed.
486 LOGIC. Lkct. XXXV.
struction, and comprise the rules by which it ought to be regulated,
in the following paragraph.
% CXIII. In regard to Written Instruction, and its profit-
able employment as a means of intellectual
in^struct^ Tna'Ts improvement, there are certain rules which
employment as a ought to be observed, ahd which together
means of inteuectuai gonstitute the Proper Method of Reading.
improvement. i o
These may be reduced to three classes, as
they regard, 1**, The Quantity, 2°, The Quality, of what is to
be read, or, 3°, The Mode of reading what is to be read.
I. As concerns the Quantity of what is to be read, there
is a single rule, — Read much, but not many works (multum
non multa).
II. As concerns the Quality of what is to be read, — there
may be given five rules. 1°, Select the works of principal
importance, estimated by relation to the several sciences them-
selves^ or to your particular aim in reading, or to your individ-
ual disposition and wants. 2% Read not the more detailed
works upon a science, until you have obtained a rudimentary
knowledge of it in general. 3°, Make yourselves familiar with
a science in its actual or present state, before you proceed to
study it in its chronological development. 4°, To avoid errone-
ous and exclusive views, read and compare together the more
imjiortant works of every sect and party. 5°, To avoid a one-
sided development of mind, combine with the study of works
which cultivate the Understanding, the study of works which
cultivate the Taste.
III. As concerns the Mode or Manner of reading itselti
there are four principal rules. 1°, Read that you may accu-
rately remember, but still more, that you may fully understand.
2°, Strive to compass the general tenor of a work, before you
attempt to judge of it in detail. 3°, Accommodate the inten-
sity of the reading to the importance of the work. Some
books are, thei-efore, to be only dipped into ; others are
to be run over rapidly ; and others to be studied long and
sedulously. 4°, Regulate on the same principle the extracts
which you make from the works you read.*
I. In reference to the head of Quantity, the single rule is —
1 Cf. Krng, Logik, i 180. ~ Ed. [Figchaber, der Hodegetik, § 63 p. 196; 1832. Magirus v.
Logik, p. 188, ed. 1818. Scheidler, Grundriss Lectio.]
Lect. XXXV. LOGIC. 48T
Read much, but not many works. Though this golden rule has
risen in importance, since tlie world, by the art
Explication. ^^ printing, has been overwhelmed by the mul-
I. Quantity to be '^ ^ . r • i i
j.ga^ titude of books, it was still fully recognized by
Rule. the great thinkers of antiquity. It is even
Solomon. hinted by Solomon, when he complains that
Quintiiian. " of making many books there is no end."^ By
Younger Pliny. Quintiiian, by the younger Pliny, and by Seneca,
®®°^*'"' the maxim, "multum legend um esse, non multa,"
Luther quoted. ^^ laid down as the great rule of study.^ "All,"
says Luther, in his Table Talk,'' " who would
study with advantage in any art whatsoever, ought to betake them,
selves to the reading of some sure and certain books oftentimes over;
for to read many books produceth confusion, rather than learning,
like as those who dwell everywhere, are not anywhere at hoine."
He alludes here to the saying of Seneca, " Nusquam est qui ubique
est." * " And like as in society, we use not daily the community of
all our acquaintances, but of some few selected friends, even so
likewise ought we to accustom ourselves to the best books, and to
make the same fimiliar unto us, that is, to have them, as we use to
say, at our fingers' ends." The great logician,
Sanderson. , , ,, , i t p i /• t
Jiishop banderson, to Avhom 1 lormerly reierred,
as his friend and biographer Isaac Walton informs us, said " that he
declined reading many books ; but what he did read were well
chosen, and read so often that he became very familiar with them.
They were principally three, — Aristotle's Rhetoric^ Aquinas's Se-
cunda Secrindce, ^xi(\ Cicero, particularly his Offices."^ The great
Lord Burleigh, we are told by his biographer,
Lord Burk'igli. . , ^~, T-v>^/r».. • ^ a- ii tu
carried Cicero JJe O^ffims, with Aristotle s lihet-
oric, always in his bosom ; these being complete pieces, " that
would make both a scholar and an honest man."
"Our age," says Herder, "is the reading age;"
and he adds, "it would have been better, in my opinion, for the
world and for science, if, instead of the multitude of books which
now overlay us, we possessed only a few works good and sterling,
and which, as few, would, therefore, be more diligently and pro-
foundly studied." * I might quote to you many other testimonies
1 Eccles. xii. 12. — Ed. * Epist., ii. — Ed.
2 Quintiiian, x. 1, 59. Pliny, Ep., vii. 9. 5 See Walton's Lives of Donne, Wotton,
Seneca, De TranquiU. Animi, C. 9. Epist., 2, Hooker, Herbert, and Sanderson, vol. ii., p. 287,
45. — Ed. ed. Zouch, York, 1817. — Ed.
3 No. DCCCXLIV. Of Learned Men. — 6 Briefe ilber das Stud, der Theol. B. xlix.,
Ed. Werke, xiv. 267, ed. 1829. — Ed.
4^ LOGIC. Lect. XXXV.
to the same effect; but testimonies are useless in support of so
manifest a truth.
For what purpose, — - with what intent, do we read ? We read
not for the sake of reading, but we read to the
ing. ^^^^j ^^^^ ^^ may think. Reading is valuable
only as it may supply to us the materials which the mind itself
elaborates. As it is not the largest quantity of any kind of food,
taken into the stomach, that conduces to health, but such a quan-
tity of such a kind as can be best digested ; so it is not the greatest
complement of any kind of information that improves the mind,
but such a quantity of such a kind as determines the intellect to
most vigorous energy. The only profitable reading is that in
which we are compelled to think, and think intensely ; whereas
that reading which serves only to dissipate and divert our thought,
is either positively hurtful, or useful only as r.n occasional relaxa-
tion from severe exertion. But the amount of vigorous thinking
is usually in the inverse ratio of multifarious reading. Multifarious
reading is agreeable ; but, as a habit, it is, in its way, as destructive
to the mental as dram-drinking is to the bodily health.
II. In reference to the quality of what is to be read, the First of the
five rules is — 'Select the works of principal im-
ir. Quality of what portauce, in accommodation either to the several
iK to be read. * . ....
-,. ,„ , sciences themselves, to your iiarticnlar ami m
First Rnle. , ...
reading, or to your individual disposition and
wants.' This rule is too manifestly true to require any illustration of
its truth. No one will deny that for the accomplishment of an end
you ought to employ the means best calculated for its accomplish-
ment. This is all that the rule inculcates. But while there is no
difficulty about the expediency of obeying the rule, there is often
wjnsiderable difficulty in obeying it. To know what books ought
to be read in order to learn a science, is in fact frequently obtained
after the science has been already learned. On this point no gen-
eral advice can be given. We have, on all of the sciences, works
which profess to supply the advice which the student here requires.
But in general, I must say, they are of small assistance in pointing
oat what books we should select, however useful they may be in
showing us what books exist upon a science. In this respect, the
British student also labors under peculiar disadvantages. The libra-
ries in this country are, one and all of them, wretchedly imperfect ;
and there are feW departments of science in which they are not des-
titute even of the works of {irimary necessity, — works which, from
their high price, but more frequently from the difficulty of proCuT'
ing them, ai:e beyond the reach of ordinary readers.
Lkct. XXXT. LOCfliC. 489
Under the head of Quality the Second Rule is — 'Read not the
more detailed works upoh a science, until you
have obtained a rudimentary knowledge of it in
general.' The expediency of this rule is sufficiently apparent. It
is altogether impossible to read ipith advantage an extensive work
on any branch of knowledge, if we are not previously atvare of its
general bearing, and of the relations in which its several parts
stand to each other. In this case, the mitod is overpowered aftd
oppressed by the mass of details presented to it, ^^ details, the sig-
nificance and subordination of which it is as yet unable to recog-
nize. A conspectus, — a survey of the Science as a, whole, Oxight,
therefore, to precede the !*tudy of it in its pa'ttS ; Ive should be
aware of its distribution, before we attend to what is distributed, ^-
We should possess the empty frame-work, before we collect the
materials with which it is to be filled. Hence the utility of an ency-
clopgedical knowledge of the sciences in general, preliminary to a
study of the several sciences in particular ; that is, a summary
knowledge of their objects, their extent, their connection with each
other. By this means the student is enabled to steer his Way on
the wide ocean of science. By this means he always knows where-
abouts he is, and becomes aware of the point towards which his
author is leading him.
In entering upon the study of such authors as Plato, Aristotle,
Descartes, Spinoza, Leibnitz, Locke, Kant, etc., it is, therefore,
proi>er that we first obtain a preparatory acquaintance tvith the
scope, both of their philosophy in general, and of the particular
Work on which we are about to enter. In the case of writers of
such ability this is not difl[icult to do, as there are abundance of
subsidiaiy works, affording the preliminary knowledge of which we
are in quest. But in the case of treatises where similar assistance
is not at hand, we may often, in some degree, prepare ourselves for
a i-egular perusal, by examining the table of contents, and taking a
cursory inspection of its several departments. In this respect, and
also in others, the following advice of Gibbon to young students is
highly deserving of attention. "After a rapid
on quo e . gJance (I translate from the original French) —
after a rapid glance on the subject and distribution of a new book,
I suspend the reading of it, which I only resume after having my-
self examined the subject in all its relations, — after having called
up in my solitary walks all that I have read, thought, or learned in
regard to the subject of the whole book, or of some chapter in })ar-
licular. I thus place myself in a condition to estimate what the
author may add to my general stock of knowledge ; and I am thus
62
490
LOGIC.
Lect. XXXV
Third Bale.
Fourth Bale.
sometimes favorably disposed by the accordance, sometimes armed
by the opposition, of our views." ^
The Third Rule under the head of Quality is — 'Make your-
selves familiar with a science in its present
state, before you proceed to study it in its
chronological development.' The propriety of this procedure is
likewise manifest. Unless we be acquainted with a science in its
more advanced state, it is impossible to distinguish between what
is more or less important, and, consequently, impossible to deter-
mine what is or is not wortliy of attention in the doctrines of its
earlier cultivators. We shall thus also be overwhelmed by the
infinitude of details successively presented to us ; all will be confu-
sion and darkness, where all ought to be order and light. It is
thus improper to study philosophy historically, or in its past prog-
ress, before we have studied it statistically, or in its actual results.
The Fourth Rule under the same head is — 'To avoid erroneous
and exclusive views, read and compare together
the more important works of every party.' In
proportion as different opinions may be entertained in regard to the
objects of a science, the more necessary is it that we should weigh
with care and impartiality the reasons on which these different
opinions rest. Such a science, in particular, is philosophy, and such
sciences, in general, are those which proceed out of philosophy. In
the philosophical sciences, we ought, therefore, to be especially on
our guard against that partiality which considers only the argu-
ments in favor of particular opinions. It is true that in the writ-
ings of one party we find adduced the reasons of the opposite
party ; but frequently so distorted, so mutilated, so enervated, that
their refutation occasions little effort. We must, therefore, study
the arguments on b.oth sides, if we would avoid those one-sided
and contracted views which are the result of party-spirit. The
precept of the Apostle, "Test all things, hold fast by that which is
good," is a precept which is applicable equally in philosophy as in
theology, but a prece})t that has not been more frequently neglected
in the one study than in the other.
The Fifth Rule under the head of Quality is — ' To avoid a one-
sided development of mind, combine with the
study of works which cultivate the Understand-
ing, the study of works which cultivate the Taste.' The propriety
Fifth Bule.
1 The substance of the abovo pnssa;;e is
given in English, in Gibbon's Mewoirx o/my
Life and Writingf, pp. 54, 5o; I'd. 1837. The
French original is quoted bf Scheidler, Hod*-
getik, i 66, p. 204. — Ed.
Lect. XXXV. LOGIC. 491
of this rule requires no elucidation ; I, therefore, pass on to the
third head ■ — viz., the Manner of reading itself;
III. Manner of ^^^^^ ^j^.^j^ ^^^ p-^.^^ j^^j^ is— 'Read that
Reading. . ,
. „ you may accurately remember, but still more
First Rule. -^ •' ^ „ , . ,
that you may fully understand.
This also requires no comment. Reading should not be a learn-
ing by rote, but an act of reflective thinking. Memory is only a
subsidiary faculty, — is valuable merely as supplying the materials
on which the understanding is to operate. We read, therefore,
principally, not to remember facts, but to understand relations. To
commit, therefore, to memory what we read, before we elaborate it
into an intellectual possession, is not only useless but detrimental ;
for the habit of laying up in memoiy what has not been digested
by the undei"standing^ is at once the cause and the eflect of mental
weakness.
The Second Rule under this head is — 'Strive to compass the
general tenor of a work, before you attempt to
judge of it in detail.' Nothing can be more
absurd than the attempt to judge a part before comprehending the
whole; but unfortunately nothing is more common, especially
among professional critics, — reviewers. This proceeding is, how-
ever, as frequently the effect of wilful misrepresentation, as of
unintentional error.
The Third Rule under this head is — ' Accommodate the inten-
sity of the reading to the importance of the
work. Some books are, therefore, to be only
dipped into ; others are to be run over rapidly ; and others to be
studied long and sedulously.' All books are not to be read with
the same attention ; and, accordingly, an ancient distinction was
taken of reading into lectio cursoria and lectio stataria. The for-
mer of these we have adopted into English, cur-
, . sory readmg bemg a lammar and correct trans-
Lectio stalarta. ^ ^ "
lation of lectio cursoria. But lectio stataria
cannot be so well rendered by the expression of stationary read-
ing. " Read not," says Bacon, in his Fiftieth Essay — " read not to
contradict and confute, nor to believe and take
for granted, nor to find talk and discourse, but
*;0 weigh and consider. Some books %re to be tasted, others are to
be swallowed, and some few to be chewed and digested ; tliat is,
some books are to be read only in parts ; others to be read, but not
curiously ; and some few to be read wholly and with diligence and
attention. Some books also may be read by deputy, and extracts
made of them by others ; but that would be only in the less impor-
492 LOGIC. Lect. XXXV.
tant arguments, and the raean^ sort of books > else distilled books
are, like common distilled waters, fleshy things." " One kind of
books," says the great historian, Johann von Mullet,^ " I fead witli
great rapidity, for in these there is much 4rosi^
to throw aside, and little gold to be found;
some, however, there are all gold and diamonds, and he who, for
example, in Tacitus can read more than twenty pages in four boars,
certainly does not understand him."
Rapidity in reading depends, however^ greatly on our acquaint-
ance with the subject of discussion. At first, upon a science we
can only read with profit few books, and laboriously. By degrees,
however, our knowledge of the mattere treated expands, the reason-
ings appear more manifest^ — we advance more easily, until at
length we ai'e able, without overlooking anything of importance,
to read with a velocity which appears almost incredible for those
who are only commencing the study.
The Fourth Rule under this head is — 'Regulate on the same
principle the extracts which you make from the
Fourth fiiile. , ■, ,
works you read.
So much for the Unilateral Communication of thouglit, as a
meaA of knowledge. We now proceed to the Mutual Communica-
tion of thought, — Conference.
This is either mere Convei-sation, — mere Dia-
kh.dr'^"'^"*''^"" logue, or Formal Dispute, and at present we
consider both of tliese exclusively only as a
means of knowledge, — only as a means for the conimnnicntion of
truth.
The employment of Dialogue as such a mean, requires great skill
and dexterity ; for presence of mind, confidence,
laogue. ^^^^ ^^j pliability are necessary for this, and
these are only obtained by exercise, independently of natural talent.
This was the metliod which Socrates almost exclusively employed
in the communication of knowledge ; and he called it his art of
inteliectiial midwifery, because in it« application truth is not given
over by the master to the disciple, but the master, by skilful ques-
tioning; only helps the disciple to deliver himself of the truth explic-
itly, whicl) his mind had before held imi)licitly. This method is not,
however, applicable to all kiilds of knowledge, but only to those
which the human intellect is able to evolve out of itself, that is,
only to the j.'ognitions of Pure Reason. Disputation '\% of two prin-
cipal kinds^ inasmuch as it is oral or written; and in botli cases, the
controversy may be conducted either by the rules of strict logical
J W'Tke, Iv 177 Cf. xvii. 263. Quoted by Scheldler, Hodegttik. » 66, p. 204 — Ed
Lect. XXXV. LOGIC. 493
disputation, or left to the freedom of debate. Without entering on
details, it may be sufficient to state, in regard to
2. Disputation,— Logical Disputation, that it is here essential
Oral and Written. ^i, ^ ^u • . • ^- ^i ^ ^
Academical dis u- pomt m question, — the status contro-
tation. versice, — the thesis, should, in the first place, be
accurately determined, in order to prevent all
logomachy, or mere verbal wrangling. This being done, that dis-
putant who denies the thesis, and who is called the opponent, may
either call upon the disputant who affirms the thesis, and who is
called the defendant, to allege an argument in its support, or he
may at once himself produce his countei'-argument. To avoid,
however, all misunderstanding, the opponent should also advance
an antithesis, that is, a proposition conflictive with the thesis, and
when this has been denied by the defendant the process of argu-
mentation commences. This proceeds in regular syllogisms, and is
governed by definite I'ules, which are all so calculated that the dis-
cussion is not allowed to wander from the point at issue, and each
disputant is compelled, in reference to every syllogism of his adver-
sary, either to admit, or to deny, or to distinguish.' These rules
you will find in most of the older systems of Logic ; in particular
I may refer you to them as detailed in Heerebord's Praxis Logica,
to be found at the end of his edition of the Synopsis of Burgersdi-
cius. The practice of disputation was long and justly regarded as
the most important of academical exercises ; though liable to abuse,
the good which it certainly ensures greatly surpasses the evil which
it may accidentally occasion.
1 Cf. KruK, Logik, § 186. Amu. 2. Scbeidler, Hbdegetik, { 45, p. 138. — £»
APPENDIX.
I.
THE CHARACTER AND COMPREHENSION OF LOGIC— A
FRAGMENT.
(See page 3.)
In the commencement of a course of academical instruction, there are
usually two primary questions which obtrude themselves ; and with the answer
to these questions I propose to occupy the present Lecture.
The first of these questions is, — What is the character and comprehension
of the subject to be taught? The second, — What is the mode of teaching
it? In regard to the former of these, the question, — What is to be taught, —
in the present instance is assuredly not superfluous. The subject of our course
is indeed professedly Logic ; but as under that rubric it has been too often the
practice, in our Scottish Universities, to comprehend almost everything except
the science which that name properly denotes, it is evident that the mere inti-
mation of a course of Lectures on Logic does not of itself definitely mark out
what the professor is to teach, and what the student may rely on learning.
I shall, therefore, proceed to give you a general notion of what Logic is, and
of the relation in which it stands to the other sciences ; for Logic — Logic
properly so called — is the all-important science in which it is at once my duty
and my desire fully and faithfully to instruct you.
The very general — I may call it the very vague — conception which I can
at present attempt to shadow out of the scope and nature of Logic, is of course
not intended to anticipate what is hereafter to be articulately stated in regard
to the peculiar character of this science.
All science, all knowledge, is divided into two great branches ; for it is
either, 1°, Conversant about Objects Known, or, 2°, Conversant about the
Manner of knowing them, in other words, about the laws or conditions under
which such objects are cognizable. The former of these is Direct Science, or
Science simply; the latter. Reflex Science, — the Science of Science, or the
IVIethod of Science.
Now of these categories or great branches of knowledge, Simple Science, or
Science directly conversant about Objects, is again divided into two branches j
496. APPENDIX.
for it is either conversant about the phaenomcria of the internal world, as re-
vealed to us in consciousness, or about the phasnomena of the external world,
as made known to us by sense. The former of these constitutes the Science
of Mind, the latter the Science of Matter; and each is again divided and sub-
divided into those numerous branches, which together make up nearly the
whole cycle of human knowledge.
The other category — the Sciene* of Science^ or the Methodology of Sci-
ence— falls likewise into two branches, according as tlie conditions which it
considers are the laws which determine the possibility of the mind, or subject
of science, knowing, or the laws which determine the possibility of the exist-
ence, or object of science, being known ; Science, I repeat, considered as
reflected upon its own conditions, is twofold, for it either considers the laws
under which the human mind can knpw, or the laws under which what is pro-
T)osed by the human mind to know, can be known. Of these two sciences of
scipnce, tjie former — that which treats of those conditiofls of k.upwledge which
lie in the nature of thought itself — is Logic, properly so called; the latter, —
that which treats of those conditions of knowledge which lie in the nature, not
of thought itself, but of that which we thinlc about, — this has as yet obtained
no recognized appellation, no name by which it is universally and familiarly
known. Various deqomiijations have indeed been given to it in its several
parts, or in its special relations ; thus it has been called Heuretic, in so fai- as it
expoimds the rules of Invention or Discovery, Architectonic, in so far as it treats
of the method o.f building up our observations into system; but hitherto it has
obtained, as a whole, no adequate and distiuctive title. The consequence, or
perhaps the cause, of this wapt of a peculiar name to mark out the second
science of science, as distinguished from the first, is that the two have fre-
quently been mixed up together, and that the naiue o( Logic has been stretched
so as to comprehend the confused assemblage of their doctrines. Of these two
sciences of the conditions of knowledge, the one owes its systematic develop-
ment principally to Aristotle, the other to Bacon ; though neither of these
philosophers has precisely marked or rigidly observed the limits which separati»
them from each other ; and from the circumstance, that th<^ latter gave to his
great Treatise the name of Organum, — the name which has in later times
been applied to designate the complement of the Logical Treatises of the for-
mer, — from this circumstance, I say, it has often been supposed that the aim
of JJacon was to build up a Logic of his own upon the ruins of the Aristotelic.
Nothing, however, can be more erroneous, either as to Bacon's views, or as to
the relation in which the two sciences nmtually stand. These are not only not
inconsistent, they are in fact, as correlative, each necessary to» each dependent
on, the other ; and although they constitute two several doctrines, which must
be treated in the first instance each by and for itself, they are, however, in the
last resort oiily two phases, — two members, of one great doctrine of method,
which considers, in the counter relations of thought to the object, and of the
object to thought, the universal conditions by which the possibility of bum^n
knowledge is regulated and defined.
But allowing th^P term Logic to be extended so as to denote the genus of
which these opposite doctrines of Method »re the species, it will, however, be
necessary to add a difference by which these special Logics may be distin-
APPENDIX. 497
guished from each other, and from the generic science of ■which they are the
constituents. The doctrine, therefore, which expounds the laws by which our
scientific procedure should be governed, in so far as these lie in the forms of
thought, or in the conditions of the mind itself, which is the subject in which
knowledge inheres, — this science may be called Formal, or Subjective, or Ab-
stract, or Pure Logic. The science, again, which expounds the laws by which
our scientific procedure should be governed, in so far as these lie in the
contents, materials, or objects, about which knowledge is conversant, — this
science may be called Material, or Objective, or Concrete, or Applied Logic.
Now it is Logic, taken in its most unexclusive acceptation, which will con-
stitute the object of our consideration in the following course. Of the two
branches into which it falls. Formal Logic, or Logic Proper, demands the
principal share of our attention, and this for various reasons. In the first
place, considered in reference to the quantity of their contents. Formal Logic
is a far more comprehensive and complex science than Material. For, to speak
first of the latter : — if we abstract from the specialities of particular objects
and sciences, and consider only the rules which ought to govern our procedure
in reference to the object-matter of the sciences in general, — and this is all
that a universal logic can propose, — these rules are few in number, and their
applications simple and evident A Material or Objective Logic, except in
special subordination to tlie circumstances of particular sciences, is, therefore,
of very narrow limits, and all that it can tell us is soon told. Of the former,
on the other hand, the reverse is true. For though the highest laws of thought
be few in number, and though Logic proper be only an articulate exposition of
the universal necessity of these, still the steps through which this exposition
must be accomplished are both many and multiform.
In the second place, the doctrines of Material Logic are not only far fewer
and simpler than those of Formal Logic, they are also less independent ; for
the principles of the latter once established, those of the other are either im-
plicitly confirmed, or the foundation laid on which they can be easily rested.
In the third place, the study of Formal Logic is a more improving exercise ;
for, as exclusively conversant with the laws of thought, it necessitates a turn-
ing back of the intellect upon itself, which is a less easy, and, therefore, a more
invigoi-ating, energy, than the mere contemplation of the objects directly pre-
sented to our observation.
In the fourth place, the doctrines of Formal Ix)glc are possessetl of an in-
trinsic and necessary evidence ; they shine out by their native light, and do not
require any proof or corroboration beyond that which consciousness itself sup-
plies. They do not, therefore, require, as a preliminary condition, any ap-
paratus oi acquired knowledge. Formal Logic is, therefore, better fitted than
Material for the purposes of academical instruction; for the latter, primarily
ctmversant with the conditions of the external world, is in itself a less invig-
orating exercise, as determining the mind to a feebler and more ordinary
exertion, and, at the same time, cannot adequately be understood without the
previous possession of such a ctMnplement of information as it would be unrea-
sonable to count upon in the case of those who are only commencing their
philosophical studies. '
68
498 APPENDIX.
II.
GENUS OF LOGIC.
(Seepage?.)
I. — Science.
A. Affirmative. — Stoici (v. Alexander Aphrod. In Topica, Prooem. ; Diog-
enes Laertius, Vita Zenonis, L. vii., § 42). " Plato et Platonici et Academici
omues" (v.Camerarius, Selectee Disput. Philos. Pars, i., qu. 3, p. 30).
(a) SPECULATIVE SCIENCE.
Toletus, In Un. Arist. Log., De Dial, in Comniuni, Qu. ii., iv. Suarez, Disp.
Metaph., Disp. i. § iv. 26 ; Disp. xliv. § xiii. 64. " Comniuniter Thomistse, ut
Capreolus, Sotus, Masius, Flandra, Soncinas, Javellus : Omnes fere Scotist89
cum Scoto, ut Valera, Antonius Andreas, etc." (v. Udephonsus de Penafiel,
LogiccB Disputationes, Disp. i. qu. 4. Cursus, p. 79.) For Aquinas, Durandus,
Niphus, Canariensis, see Antonius Ruvio, Com. in Arist. Dialect., Prooem. qu.
5. For Bacchonus, Javellus, Averroes, see Conimbricenses, In ArisL Dial.
Prooem. Q. iv. art. 5. Lalemandet, Cursus Phil., Logica, Disp. iii. part iii.
Derodon, Logica Restit., De Genere, p. 45. Camerarius, Disp. Phil., Pars i.,
qu. 3, 4. (That Logica docens a true science.) For Pseudo-Augustinus, Av-
icenna, Alpharabius, see Conimbricenses, Com. in Arist. Dial. Prooem. Qu. iv.
art. 3. For Boethius, Mercado, Vera Cruce, Montanesius, see Masius, Com. in
Porph. et in Universam Aristotelis Logicam, Sect, i., Prooem. qu. v. et seq.
Poncius, De Nat. Log., Disp. ii., concl. 2. For Rapineus, Petronius, Faber,
see Camerarius, Sel. Disp. Phil., Pars i., qu. 4, p. 44.
(b) rSACTICAL SCIENCE.
Conimbricenses, In Universam Aristotelis Dialecticam. Prooem. Qu. iv., art.
5. Fonseca, In Metaph. L. ii. c. 3, qu. 1, § 7. For Vcnetus, Albertus Magnus,
Jandunus, see Ruvio, I. c. Schuler, Philosophia nova Methodo Explicata, Pars
Prior, L. v. ex. i., p. 306. (1603). D'Abra de Raconis, Summa Totius Philoso-
phice. Log. Prcel., c. i. Isendoorn, Cursus Logicus, L. i., c. 2, qu. 7. Biel, In
Sentent., L. ii. Prol. Occam, Sumina Totius Logicce, D. xxxix. qu. 6. For
Aureolus, Bern. Mirandulanus, see Conimbricenses, I. c. For Mathisius, Murcia,
Vasquez, Eckius, see Camerarius, Sel. Disp. Phil. Pars i., qu. 4, p. 44. Ude-
phonsus de Penafiel, Log. Disp. D. i. qu. 4, sect. 2. Oviedo, Cursus Philo-
sophicus, Log., Contr. Prooem. ii. 5. Arriaga, Cursus Philosophicus, Disp. iii. § 4.
(c) SPECULATIVE AND PRACTICAL.
Hurtado de Mendoza, Log. Disp. D. ii. § 2.
B. Negative. — For almost all the Greek commentators, see Zabarella, Opera
APPENDIX. 499
Logica, De Nat. Log., L. i, c. 5, and Smiglecius, Logica, D. ii. qu. 5. See also
Ildephonsus de Penafiel, Disp. Log. D. i. qu. 1, § 1, p. 67.
II. — Art.
Scheiblcr, Opera Logica, Pars. i. c. 1, p. 49. J. C. Scaliger, Exercitationes,
Exerc. i. 3. G. J. Vossius, De Natura Arfium, L. iv., c. 2, § 4. Balforeus, In
Org. Q. V. § G, Prooem., p. 31. Burgersdicius, Instilutiones LogiccE. Lib. i. c.
1. Paoius, Comm. in Org. p. 1. Sanderson, Log. Artis Compendium, L. i. c. 1,
p. 1, Cf. p. 1!)2. Aldrich, Artis Log. Compendium. L. i. c. 1, p. 1. Hildenius,
Qucestiones et Commentaria in Orgunon, p. 579 (1.585). Goclenius, Problemata
Logica et Philosopfiica. Pars. i. qu. 3. Bamus, Dialectica. L. i. c. 1. Augus-
tinus, De Ordine, ii. c. 15. Cicero, De Claris Oralorihus, c. 41. De Oratore, L.
ii., c. 38. Lovanienses, Com. in Arist. Dial. Praef. p. 3. Rodolphus Agricola, De
Dialecticce Invenlione, L. ii. p. 255. Monlorius (Bapt.), Comm. in Anal. Pr.
Prajf. Nunnesius, De Constitut. Dial., p. 43. Downam (Ramist), Comm. in Ram.
Dial., L. i. c. 1. p. 3. Paraeus, Ars Logica, p. 1, 1670. For Horatius Corna-
chinus. Ant. Bernardus Mirandulanus, Flammiaius Nobilius, see Camerarius,
-Se/. Disp. Phil. Pars. i. q. 3, p. 30.
III. — SciExcK AND Art.
Lalemandet, L/)g., Disp. iii. Part iii. el. 4. (Logica tUens, an art ; Logica do-
cens, a speculative science.) Tartaretus, In P. Hispannm, f. 2 (Practical Sci-
ence and Art.) P. Hispanus, Copulata Omn. Tractat. Pet. Hisp. Parv. Logical,
T. i. f. 10, 1490. Philosopkia Vetus et Nova in Regia Burgundia olim Pertrac-
taia, Logica, T. I., pp. 58. 59. 4th ed. London, 1685. Tosca, Comp. Phil.
Log., Tr. i. 1. iv. c. 4, p. 208 (Practical Science and Art). Purchot, Instit.
Phil., T. L Prooem. p. 36. Eugenius, Aojikt}, pp. 140, 141. Dupleix, Logique,
p. 37. Facciolati, Rudimenta Logical, p. 5. Schmier, Philosophia Quadripartita
(v. Henmannus, Acta Philosoph. iii. p. 67). Aquinas (in Caramuel, Phil. Realis
el Rationalis, Disp. ii. p. 3).
IV. — Neither Science nor Art, but Instrument, Organ, or Habit, or
Instrumental Discipline.
Philoponus, In An. Prior., initio. For Ammonius (Prcef. in Prced.'), Alex-
ander (In Topica, i. c. 4 ; Metaph. ii. t. 15). Simplicius, (Prcef. in Prced.},
Zabarella (De Natura Logicce, L. i. c. 10.), Zimara (In Tabula v. Absurdum),
Averroes, see Smiglecius, Logica, Disp. ii. qu. 6, p. 89. Aegidius, In An. Post.
L. i. qu. 1. For Magnesius, Niger (Petrus), Villalpandeus, see Ruvio, In Aritt.
Dial., prooem. qu. 2. F. Crellius, Isagoge Logica, L. i. c. 1, p. 5. P. Vallius,
Logica, T. I. prooem. c. i. et alibi. Bartholinus, Janitores Logici, II. pp. 25 and
76. Bertius, Logica Peripatetica, pp. 6, 10. Themistius, An. Post. i. c. 24.
Aquinas, Opuscula, 70, qu. De Divisione Sciential Specidativce, — sed alibi sci-
entiam vocat. (See Conimbricenses, In Arist. Dial., T. I. qu. iv. art. 5, p. 42.)
Balduinus, In Qucesito an Logica sit Scientia. Scaynus, Paraphrasis in Organo''
Prief. p. 9.
500
APPENDIX.
"V. — That, looselt takiwo the terms, Logic is either Art or Sctbscs,
OR both.
Zabarella, Opera Logica, De Nat, Log., L. i. c. viii. D'Abra de Raconis,
Summa Tot. Phil. Prcel. Log., L. iii., c. 1, p. 8, ed. Colon. (Practical Science).
Balforeus, In Organon, Q. v. §§ 1, 6, pp. 20, 32. (Art). Dero<lon, Logica RestiL
De Procem. Log., p. 49, (Speculative Science). Crellius, Isogoge, pp. 1, 4.
Bertius, Logica Peripatetica, pp. 11, 13. Aldrich, Art. Log. Comp., L. ii. c. 8,
T. i. (Art). Sanderson, Log. Art. Comp. Append. Pr., c. 2, page 192. (Art).
Conimbricenses, In Arift. Dial., T. I., p. 33 (Practical Science). Philosophia
Burgundia, T. I. pp. 56, 59. Eustachius, Summa Philosophice, Dialectica Quosit.
Prooem., i. p. 4. Nunnesius, De Constit. Dial.,ff, 43,68. Scheibler, Opera Log-
ica, pp. 48, 49. Scaynus,' Par. in Org., pp. 11, 12. Camerarius, Sel. Disp. PhU^
Pars. i. qu. 3, pp. 31, 38 (Speculative Science). B. Pereira, De Commun. Prut-
dp. Omn. Rer. Natural, h. l De Phil. c. 18, p. 60, 1618.
VI. — That at once Scibkcs (fast of Philosophy) and Iksthcment or
PhIIXJSOI'HY.
Boethius, Prtef. in Porphyr. (a Victorino Transl.) Opera, p. 48. Eustachius,
Summa Philosophice, p. 8 (Scientia organica et practica). For Simplicius, Al-
exander, Philoponus, etc., see Camerarius, Sel. Disp. PhiL, p. SO. Pacius, Com. in
Arist. Org., p. 4,
Vn. — That Qcestion, whether Logic part of Philosophy or not, aw
Idle Question.
Pacius, Com. in Arist. Org., p. 4. Avicenna (in Conimbricenses, In ArisL
Dial., Qu. iv. art. 4, T. I. p. 38).
Vni. — That Question of whether Art, Sciekce, etc.. Idle — only
Verbal.
Buffier, Cours des Sciences, Seconde Logique, § 421, p. 887.
Eugenius, 'H AcryiKi], p. 140, has the following:
'* From what has been said, therefore, it clearly appears of what character
are the diversities of Logic, and what its nature. For one logic is Natural,
another Acquired. And of the Natural, there is one sort according to Faculty,
another according to Dispa4tion. And of the Acquired, there is again a
kind according to Art, and a kind according to Science. And the Native
Logic, according to Faculty, is the rational faculty itself with which every hu-
man individual is endowed, through which all are qualified for the knowledgt-.
and discrimination of truth, and which, in proportion as a man employs tbt*.
le~ss, the less is he removed from irrationality. But the Native Logic, according
to Disposition, is the same faculty by which some, when they rt-ason, are wont
to exert their cogitations with care and attention, confusedly, indeed, and un-
critically, still, however, in pursuit of the truth. The Acquired, according to
Art, is the correct and corrected knowledge of the Rules, through which the
intellectual energies are, without fault or failure, accomplished. But the Ae-
APPENDIX.
601
qaired, according to Science, is the exact and perfect knowledge both of the
enei^es themselves, and also of the causeij through which, and through which
exclusively, they are capable of being directed towards the truth."
Logic.
( N**'^^' according to j ^tspo^ion.
(. Acquired, according to ] o !
Art.
Science.
" And thus Disposition adds to Faculty consuetude and a promptness to en-
eigize. Art, again, adds to Disposition a refinement and accuracy of Energy
Finally, Science adds to Art the consciousness of cause, and the power of ren-
dering a reason in the case of all the Rules. And the natural logician may be
able, in lils random reason, to apprehend that, so to speak, one thing has deter-
mined another, although the nature of this determinatiou may be beyond his
ken. But he whose disposition is exercised by reflection and imitation, being
able easily to connect thought with thought, is cognizant of the several steps of
the reasoning process, howbeit this otherwise may be confused and disjointed.
But he who is disciplined in the art, knows exactly that, in an act of inference,
there are required three terms, and that these also should be thus or thus con-
nected. Finally, the scientific logician understands the reason, — why three
terms enter into every syllogism, — why there are neither more nor fewer, —
and why they behoove to be combined in this, and in no other fashion.
'* Wherefore to us the inquiry appears ridiculous, which is frequently, even
to nausea, clamorously agitated concerning Logic — Whether it should be re-
garded as an Art or as a Science."
III.
DIVISIONS, VARIETIES, AND CONTENTS OF LOGIC. .
(See p. 49.)
/v. Timpler, Logicce Systema, L. i. c. i.
Docens I quaest. 2, 3. Isendoom, Effaia, Cen-
,X»f>ls»pa7jiM{Tft)i'. ) turia, i. EfF. 55. Crellius, Isagoge,
J J Pars Prior, L. i. c. i. p. 12. Noldius,
L LooiCA.N Utens, \ Z^ica TJeco^nifa, Procem. p. 13.
4v XP^vu icol yvtwcuTiefJ philoponus, In. An. Pr., f. 4. Alstedius,
wpayndrwv. i Encydopcedia, pp. 29 and 406. v.
\ Aristotle, Metaph., Li vii. text, 23.
IL LOGICA,
Doctrinalis i [Objec-
Systematica ) tiva] .
Habitualis [Subjectiva].
I V. Timpler, Sgst. Log., Appendix, p.
877. Noldius, Ijog. Becog., Prooem.,
p. 13.
502
APPENDIX.
5 Pare Communis, Gene-
ralis.
Pare Propria, Specialis.
''Adopted in different significations by
Timpler, Si/st. Loi., q. 19, p. 55.
Theoph. Gale, Lacficxi, pp. 6, 246,
et seq. (1681). Crellius, Isagoge, P. i.
L. i. c. 1, p. 3. Alstedius, Encyclop.,
pp. 29 and 406.
(Para.
IV. LooicA, W ppiicata.
N. B. — Averroes (Pacins, Com. p. 2)
has Logica appropriata sen particalaris,
and Logica communis = Unirereal, Ab-
stract Logic.
V. Logica,
Abstracta.
Concreta.
Pare Communis.
VI. Logica, <( -p&n Pro- ( ■A^P<xi>ctica.
} Dialectica.
pna, i
( Sophistica.
^ T. Timpler, Sifst. Log , p. 42. Isendoom.
Efata, Cent. i. ES. 56.
Vn. Logica,"
^EvpfTtic^ TCl Tonrucif.
, Inventio.
I KpiTllcfl.
Judicium.
^Dispositio.
V. Timpler, Si/s. Log., p. 44. Crellius,
Isagoge, pp. 10, 11, and Isendoom,
Effata, Cent. i. Eff". 51. Adopted
by Agricola, Lk Inv. Died., L. i.
p. 35. Melanchthon, Erot. Dial., p.
10. Ramus, Schol. Dialect. L. i. t.
i., and L. ii. c. i. p. 351 et seq.
Spencer, Log., p. 1 1 . Downam, In
Rami Dial., L. i. c. 2, p. 14. Peri-
onius, De Dialectica, L. i. p 6
(1544). Vossius, De Nat. Artium
sive Logica, L. ir. c. ix. p. 217.
VIIL Logica,
Pars de Propositio.
Pare de Judicio.
V. Timpler, Si/st. Log., p. 49.
IX. Logica,
Doctrina Dividendi.
' Doctrina Definiendi.
Doctrina Argumeiitandi.
v. Timpler, Syst. Log., p. 51. Isen-
doom, Effata, Cent. i. Eff". 57.
Boethius, (Augustin, Fonseca, etc)
APPENDIX.
503
X. LOOICA,
Simplicis Apprehensi-
onis.
Judicii.
Batiocinatioois .
NoStica {melius Noema-|
Synthetica. tica).
Dianoetica.
fv. Timpler, S^/st. Log., 52. Isendoorn,
Effata, Cent. i. Eff. .58.
> Isendoorn, Cursus Logicus, p. 31, and
Effata, Cent. i. § 59. Noldius, Log.
Bee., p. 9. Aquinas.
XL LOGICA,
1. Ideas (notions). ^ L' Ai-t de Penser, Part i. Clericus,
2. Judgment. / Logica, adopts this division, but
3. Reasoning. ( makes Method third, Reasoning
4. Method. j fourth.
XII. Logica,
■i:
Doctrine of Elements.
Doctrine of Method.
Kant, Logik ; Krug, Logik.
1st. Called Analytic by Metz, Instit. Log, Twesten, Die Logik,
inshesondere die Analytik, p. lii. Esser, Logik Part i.
2d. Called Systematic or Architectonic by Bachmann, Logik,
Part ii.
Called Synthetic by Esser (who includes under it also Applied
Logic), ZyO^i'A;, Part ii.
/Thematica — de materia\
Xm Logics ) operationi Logicae /Mark Duncan, Institutiones Logicce,
' partes ) subjecta. \ Proleg. c. iii. § 2, p. 22. Burgersdi-
/ Organica — de instm- \ cius, Instit. Log., L. i. c. i. p. 5.
\ mentis sciendi. J
Communis,
Generalis.
XIV. LogicaX Specialis.
Genetiea.
1. De ordinibus rerum generalibus"
et attributis communissimis.
2. De Vocibus et Oratione.
3. De Ideis siniplicibus et appre-
hensione simplici 'dirigenda.
4. De Judicio et Propositione.
5. De Discursu.
6. De Dispositioue seu Methodo.
Genesis
sen
Inventio.
Analysis.
f Genesis stricta.
( Genesis didactica.
<■ Hermeneutica.
( Analy tica and Critica.
Analytica.
In ordine ad mentem — Logica
stricte dicta.
In ordine ad alios — Interpretativa
vel Hermeneutica genetiea.
Hermeneutica analytica.
Analytica stricta vel in specie.
Theophilus
Gale {Logica,
1681) follows
(besides Kec-
kermann and
Burgersdyk)
principally
Clauberg and
L'Art de Pen-
of Port
Royal.
504
APPENDIX-
Theoretica pars.
,,, ^ J Practica pare — (this in-, ^rr ,i. t,. .. -r, ■ ,■ -^
XV. LogicaX , j. r, Iff »i. J > Wolf, PAitos. /cafebnofjs. Pare 1. and 11.
' ^ eluding the Method- A '
ology and Applied '
Logic of S^ant.,
XVI.
On Adrastean order, etc. of the books of the Organon, rtrfc
Ramus, Sdidte Dial., L. ii., c. 8., p. 354. Piccartus, In
Organum, Prolegomena, p. 1 et seq.
1. Xlfpl tfjs wpiirTis iyvoias, or^
irfio\ii\f/fais.
partes. ) ^- ^'P] "P^"'"''
4. Tlepi Suwotas.
5. Tlepl fi(d6iov.
Eugenius Diacooos, Aajutitf f,
144.
■SGenoTCsi. A division different in some
1 . Emendatrice. I respects is given in his Latin Logic,
2. Inventrice. f Proleg. § 51, j). 22. The fourth
XVU. LoGiCA,'<( 3. Giudicatrice. V part of the division in the Latin
4. Rogionatrice. y Logic is omitted in the Italian, or
5. Ordinatrice. 1 rather reduced to the second; and
/ the fifth divided into two.
XVm. LooiOA,^
SPorphyrii Isag. • • • )
Praed. \ Isendoom, Effata, Cent 1.
Interpret ) Eff. 52.
( ^""(W ^ y Reason of terms, Pacius, Com
NoTa. ) ^"^y^- P'^ ( numt in Org., In Porph. Isag
/ ^<^ \ p. 3.
MX. LooiCA,< rApodictica.
/ ^vSXoyunucfi. < Topica.
\ ( Sopfaifitica.
Isendoom, Effata, Cent, i
Eff. 56. ( From John Ho»
pinian, De Ckmtrovenrh
Dialecticis.)
• 'SroixtioXoyiK^i.
^
.
( Prior. j
Yoesius, De Natura
XX. LooiCA, ^
\ { Analytica.
\ Posterior, v
, Artium sive tie Lo-
/
1 XvWayttrrur^. J
J Dialectica.
( Topica. I
gica, L. iv. c. ix.
^ ^
( Sophistic*. ]
p. 220.
( Analytica.
XXL LoGicA/
\
APPENDIX. 505
C prodromus de Interpretatione. \
} universe de Syllogismo. \
(^ speciatem de Demonstratione. f Vossius, De Na-
z' tura Artium, p.
( prodromus de Categoriis. ( 220.
-r»- 1 __• -\ de Syll. Terisimili.
Dialectica. ^ ■'
(^ de Syll. sophistico sive pirastico.
\ Dialectica.
XXIL LOGICA, -j Analytica.
) Aristotle, in Laertius v. Vossius,
r De Nat. Art. sive De Logica, L.
) iv. c. ix. § 11, p. 219.
__-.,^ ^ r -, , . ... I Stoicorum, see \ossius, De Nat.
XXIII. Logica S Rebus quae signincantur. f . . ,^ ^ • t •
.•<„., ... >- Art. sive De Loqica, L. IV. c. IX.
de i Vocibus quae significant. ^
Loquendo.
XXIV. LooiCJB } Eloquendo.
partes de ) Proloquendo.
Proloquiorom summa.
Varro, vide Vossius, De Nat. Art.,
L. iv. c. ix. § 8, p. 219.
( nphs tSpeffiy.
XXV. Logica, < upbs Kplaw.
Logicse
partes.
) Aristotle (?) in Laertius, L. v. § 28,
>• p. 284. Alexander Aphrod. in
y nota Aldobrandini.
i'NoTiTucfi, Apprehensiva. \
Kpiaifios vel Kpirufff, t Caramuel Lobkowitz, Batioualii et
Judicativa. / Realis Phihsophia, Logica seu
AioXfKTucfi, Argumenta- V PAH. Bat. Disp. ii. p. 3.
\ tiva.
. r Divisio.
^"^ ^ Definitio.
partes, )
(_ Argnmentatio.
r Apodictica.
J Dialectica.
• V. Crellius, Isagoge, Pars, prior, c. i. p. 10.
T. Crellius, Isagoge, Pars, prior, c. i. p. 10.
Isendoom, Effata, Cent. i. Eflf. 54.
( Sophistica.
< ^ . r Crellius, Isanoge, Pars, prior, c. i. p. 10
partes, | Topica. i ^'^ ' f > r
Stoicheiology (pure) should contain the doctrine of Syllogism, without dis-
tinction of Deduction or Induction. Deduction, Induction, Definition, Division,
64
506 APPENDIX.
from the laws of thought, should come under pure Methodology. All are pro-
cesses (v. Caesalpinus, Qucest. Perip. sub init.)
Perhaps, 1°, Formal Logic (from the laws of thought proper) should be
dlstin»uished from, 2°, Abstract Logic (material, but of abstract general mat-
ter) ; and then, 3°, A Psychological Logic might be added as a third part,
considering how Reasoning, etc., is affected by the constitution of our minds.
Applied Logic is properly the several sciences.
Or may not Induction and Deduction come under abstract Material Logic ?
LAWS OF THOUGHT.
(Seep. 60.)
C is either r or uon r.
The laws of Identity and Contradiction, each infers the other, but only
through the principle of Excluded Middle; and the principle of Excluded
Middle only exists through the supposition of the two others. Thus, the prin-
ciples of Identity and Contradiction cannot move, — cannot be applied, except
through supposing the principle of Excluded Middle ; and this last cannot be
conceived existent, except through the supposition of the two former. They
are thus coordinate but inseparable. Begin with any one, the other two
follow as corollaries.
I. — Primary Laws of Thought, — in general.
See the following authors on : — Dreier, Dbput. ad Ph'dosophiam Primam,
Disp. V. Aristotle, Anali/t. Pout. i. c. 11, §§ 2, 3, 4, 5, 6, 7. Schramm, Philoso-
phia Aristotelica, p. 36. Lippius, Metaphjsica Magna, L. i. c. i., p. 71 et seq.
Stahl, Rer/ulce Philosophicce, Tit. i., reg. i. p. 2 et seq., reg. ii. p. 8 et seq., Tit,
xix. reg. viii., p. 520 et seq. Chauvin, Lexicon PhUosophicum, v. Metaphysica.
Bisterfeld evolves all out of ens, — ens est. See PhUosophia Prima, c. ii. p. 24
et seq, Bobrik, System der Loyik, § 70, p. 247 et seq.
APPENDIX. 607
Laws of Thought are of two kinds : — 1". The laws of the Thinkable, —
Identity, Contradiction, etc. 2°. The laws of Thinking in a strict sense — viz.
laws of Conception, Judgment, and Reasoning. See Scheidler, Psychologic, p.
15, ed. 1833.
That they belong to Logic : — Ramus, ScJid. Dial., L. ix., p. 549.
Is Affirmation or Negation prior in order of thought ? and thus on order and
mutual relation of the Laws among themselves, as coordinate or derived ; (see
separate Laws). Fracastorius, Opera, De Intellecdone, L. i. f. 125 b., makes
negation an act prior to affirmation ; therefore, principle of Contradiction prior
to principle of Identity. — Fisser, Logik, § 28, p. 57. Sigwart, Ilandhuch zu
Vorlesungen ilber die Logik, § 38 et seq. Piccolomineus, De Mente Humana, L.
iii., c. 4, p. 1301, on question — Is affirmative or negative prior ? Schulz, Prilf.
der Kant. Krit. der reinen Vemunft, I. p. 78, 2d ed. Weiss, Lehrbuch der Logik,
§ 81 et seq. pp. 61, 62, 1805. Castillon, Memoires de I'Acade'mie de Berlin
(1803) p. 8 (Contradiction and Identity coordinate). A. Andreas, In Arist.
Metaph. iv. Qu. 5. p. 21. (Affirmative prior to negative.) Leibnitz, CEuvres
Philosophiques, Nouv. Essais, L. iv. ch. 2, § 1, p. 327, ed. Raspe. (Identity prior
to Contradiction.) Wolf, Ontologia, §§ 55, 288 — (Contradiction first. Identity
second). Derodon, Metapliysica, c. iii., p. 75 et seq. 1669. (Contradiction first.
Excluded Middle second, Identity third). Fonseca, In Metaph., 1. 849. Biunde,
Psychologie, Vol. I., part ii., § 151, p. 159. (That principle of Contradiction
and principle of Reason and Consequent not identical, as Won and Reimarus
holdi) Nic. Taurellus, Philosophice Triumphus, etc., p. 124. Arnheim, 1617,
" Cum simplex aliqua sit affirmatio, negatio non item, banc illam sequi conclu-
dimus," etc. Chauvin, Lexicon Philosophicum, v. Metaphysica.
By whom introduced into Logic: — Eberstein (^Uber die BescTiaffenheit der
Logik und Metaphysik der reinen Peripatetiker, p. 21, Halle, 1800) says that
Darjes, in 1737, was the first to introduce Principle of Contradiction into
Logic. TKat Buffier, ami not Reimarus, first introduced principle of Identity
into Logic, see Bobrik, Logik, § 70, p. 249.
II. — Primary Laws of Thought, — in particular.
1. Principle of Identity. " Omne ens est ens." Held good by Antonius
Andreas, In Metaph. iv., qu. 5. (apud Fonsecam, In Metaph. I. p. 849 ; melius
apud Suarez, Select. Disp. Metaph. Disp. iii. sect. iii. n. 4.) Derodon, Meta-
physica, c. iii., p. 77. J. Sergeant, Method to Science, pp. 133 — 136 and after.
(Splits it absurdly.) Boethius — " Nulla propositio est verior ilia in qua idem
praedicatur de seipso." (Versor, In P. Hispani Sum7nulas Logicales, Tr. vii.,
p. 441 (1st ed. 1487); et Buridanus, In Sophism.') " Propositiones illas oportet
esse notissimas per se in quibus idem de se ipso prsedicatur, ut ' Homo est
homo,' vel quarum prjedicata in definitionibus subjectarum includuntur, ut
' Homo est animal.'" Aquinas, Contra Gentiles, L. i. c. 10. Opera T. XYHI.
p. 7, Venet. 1786. Pjior to principle of Caalradiction — Leibnitz, Nouveaux
Essais,i). 377, Buffier, Principes du Raissonnement, H. art. 21, p. 204. Rejected
608 APPENDIX.
as identical and nugatory by Fonseca, he. eit. Suarez, loc. cU. Wolf, Onlolo-
ffla, §§ 55, 288, calls it Principium Certitudinis, and derives it from Principium
Cloatradictionis.
2. Principle of Contradiction — oliw/ta t^s iLvrnpiffeus.
Aristotle, Metaph.^ L. iii. 3 ; x. 5. (Fonseca^ In Metaph. T. I^ p, 860, L. iv.
(iii.) c. iii.) Anal. Post. L. i. c. 11 c. 2, § 13. (On Aristotle and Plato, see
Mansel's Prolegomena, pp, 236, 237.) Stahl, Reguloe Philosophiea^ Tit i. r^. i.
Suarez, Selecl Disp. Phil., Disp. iii. § 3. Timpler, Metaph. L. L, c. 8 qu. 14.
DoiXKion, Aletaphysica, p. 75 etc. Lippius, MtUiphi/sica, L. i. c. i., p. 73. Ber-
nardi, Thes. Arv^tot.^ vv. Principium, Contrail ict to. Leibnitz, (Euvres Philoso-
phiqueSy Nouv. Ess., L. iv. c. 2. Ramus, " Axioma Contradictionis," Scholee
DiaL L. ix. c. i., L. iv. c. 2, § 1, p. 548. Gul. Xylander, In.<itihitiones Aphori^iat
Logices Aristot., p. 24 (1577), "Principium priucipiorum hoc. est, lex Contra-
dictionis." Fhiloponus, iftw/Mi t^j ayrt<pcurt<es, v. In Post. An. f. 30 b. et seq.
Ammonius, i^lv»jia t^j tuni^Jurftts, In De Interpret, f. 94, Aid. 1503 ; but princi-
pium Exclusi Medii, Scheibler, T'opica^c. 19. On Definition of Contradictories,
V. Scheibler, Ibid. On Two Principles of Contradiction, — Negative and
Positive, V. Zabarella, Opera Logica, In An. Post. i. t 83, p. 807.
Conditions of. — Aristotle, Metaph., L. iv., c. 6. Bernardi, Thesartrus Arist.^
V. Contrad., p. 300.
Proof attempted by — Claubei^, Ontosophitt, § 26 (Degerando, iSstoire de
Philosophic, T. II. p- 67), through Excluded Middle.
3. Principle of Excluded Middle — i^it^fta ttcuprrucSf.
"*A^/wfi« 8iaifKTiic({i/, divisivum, dicitur a Gr«cis principium contradictionis
affirmativum ; ' Oportet de omni re affirmare aut negare,' " Groelenius, Lexicon
Philogophicum. Lat. p. 136. Zabarella, In An. Post., L. i., text 83, Opera
Logica, p. 807. Conimbricenses, In Org., II. 125. Lucian, Opera, II. p. 44
(cd. Henisterhuis). Aristotle, Metapli., L. iv. (iii.) c. 7 ; An. Post., L. i. 2 ; ii.
18 (Mansel's Prolegomena, p. 286). Joannes Philoponus (v. Bernardi, Thes. r.
ConiraiL, p. 300). Piccartus, Isagoge, pp. 290, 291. Javelins, In Metaph., L.
iv. qu. 9. Suarez, Disp. Metaph., Disp. iii., sect. 3, § 5. Stahl, Regulce Pkilos.,
Tit. i. reg. 2. Wolf, Ontologia, §§27, 29, 56, 71, 498. Fonseca, In Metaph.,
L. iv. c. iii. qu. 1. et seq., T. I. p. 850. (This principle not first) Timpler,
Metaphysica. L. ii. c. 8, qu. 15. Derodon, Metaph., p. 76. (Secundum princi-
pium.) Lippius, Metaphysica, L. L c. i-, pp. 72, 75. Chauvin, Lexicon Philo-
foi^ncum, V. Metaphysica. Scheibler, Topica, c. 19. Hurtado de Mendoza, Z)i!ip.
Meuijh., Disp. iii,, § 3 (Caramuel, Rat. et ReaL Phil., § 462, p. 68).
^\niether identical with Principle of Contradiction,
AfTirmative, — Javcllus, /. c. Mendoza, Disp. Metaph., D. iii. § 3, Leibnitz,
(Euvres Philosophiques, Nouv. Es.'i., L. iv. c. 2, p, 327.
Negative, — Fonseca, Di<<p. Met. Disp, iv. c. 3, 9. Suarez, Disp. Metaph.,
Disp. ni. § 3. Stahl, Reg. Phil. Tit. i. reg. 2.
Whether a valid and legitimate Law.
Fischer, Logii; ^ 64 el seq. (Negative), — Made first of all principles by
Alexander do Ales, Metaph., xiv. text 9 : " Conceptus onmes simplices, ut
1
APPENDIX. 609
resolvtintur ad ens, ita omnes conceptus compositi resolvtintur ad hoc princi-
pium — De quolibet affirmatio vel negado." J. Picas Mirandulanus (after Aris-
totle), Conclusiones, Opera, p. 90. Philoponus, In An. Post. i. f. 9 b, (Brandis,
Scholia, p. 199). Th 8' iircw (pdvai ^ airo((>duai, fi tls rh aSvyaTOf air6Set^is Aanfidyfi.
Aristotle, An. Post. i. c. 11. § 3. ^AyTtpcuris 5« am-ldtais f;s ovk effri fiera^v ko^
oMff. An, Post. i. c. 2, § 13. McTa|ii ijm<f»i(r&i>s ovk ivStx^^"* ov^tv. Metaph.
L. iii. C. 7. 'Eire! aini(paafas ouSci/ avk fiiaov, ^Kwtpbv on 4v rols ivamlois tarai ri
(xtra^i. Physica, L. v. c. 3, § 5. See also Post. An. L. i. c. i. § 4, p. 414 j c. 2
§ 13, p. 417 ; c. 11, § 3, p. 440. (vide Scheibler, Topica, c. 19 ; and Mansel'i
Prolegomena, p. 236, on Aristotle).
4. Principle of Reason and Consequent
That can be deduced from Principle of Contradicticm.
Wolf, Oniologia, § 70. Baumgarten, Metaphysik, § 18.
Jakob, Grundri-is der allgemeinen Logik und Kritische Angfangsgriinde der ]
allgemeinen Metaphysik, p. 38, 3d ed., 1794. (See Kiesewetter, I. c.) J
That not to be deduced from Principle of Contradiction.
Kiesewetter, Allgemeine Logik ; Weitere Auseinandersetzung, P. I. ad §§ 20,
21, p. 57 et seq. Hume, On Human Nature, Book i. part iii. § 8. Schulze,
Logik, § 18, 5th ed., 1881.
V.
NEW ANALYTIC OF LOGICAL FORMS — GENERAL RESULTS
— FRAGMENTS.
/
L — Extract fboh Pkospectus of "Essay towards a New Analytic of
Logical Forms."
(First published in 1846.1 See pp. 102, 172. — Ed.)
" Now, what has been the source of all these evils, Tpi-oceed to relate, and shall clearly con-
vince those who have an intellect and a will to attend, — that a trivial slip in the elementary
precepts of a Logical Theory becomes the cause cf mightiest errors in thai Theory itself." —
Galen. {De Temper amentis, 1. i. c. 5.)
" This New Analytic is intended to complete and simplify the old ; — to
place the keystone in the Aristotelic arch. Of Abstract Logic, the theory, in
particular of Syllogism (bating some improvements, and some errors of detail),
remains where it was left by the genius of the Stagirite ; if it have not receded.
1 An extract, corresponding in part with is republished in the Discustions on Philosopht/.,
that now given from the I'roepectus of" Essay p. 650. To this extract tlie Author has pre-
towards a New Analytic of Logical Forms," fixed the following notice regarding the dat«
610
APPENDIX.
still less has it advanced. It contains the truth ; but the truth, partially, and
not always correctly, developed, — in complexity, — even in confusion. And
why ? Because Aristotle, by an oversight, marvellous certainly in him, was
prematurely arrested in his analysis ; began his synthesis before he had fully
sifted the elements to be recomposed; and, thus, the system which, almost
spontaneously, would have evolved itself into unity and order, he laboriously,
and yet imperfectly, constructed by sheer intellectual force, under a load of
limitations and corrections and rules, which, deforming the symmetry, has seri-
ously impeded the usefulness, of the science. This imperfection, as I said, it is
the purpose of the New Analytic to supply.
" In the first place, in the Essay there will be shown, that the Syllogism
proceeds, not as has hitherto, virtually at least, been taught, in one, but in the
two correlative and counter wholes (Metaphysical) of Comprehension, and
(Logical) of Extension ; the major premise in the one whole being the minor
premise in the other, etc. — Thus is relieved a radical defect and vital inconsis-
tency in the present logical system.
" In the second place, the self-evident truth, — That we can only rationally
deal with what we already understand, determines the simple logical postulate,
— To state explicitly what is thought implicitly. From the consistent application
of this postulate, on which Logic ever Insists, but which Logicians have never
fairly obeyed, it follows : — that, logically, we ought to take into account the
quantity, always understood in thought, but usually, and for manifest reasons,
elided in its. expression, not only of the subject, but also of the predicate, of
a judgment This being done, and the necessity of doing it will be proved
against Aristotle and his repeaters, we obtain, inter alia, the ensuing results :
'• 1°. That the preinrlcsignate terms of a proposition, whether subject or predi-
cate, are never, on that account, thought as indejinite (or indeterminate) in
quantity. The only indefinite, is particular, as opposed to dejinite, quantity ;
and this last, as it is either of an extensive maximum undivided, or of an exten-
sive minimum indivisible, constitutes quantity universal (general), and quantity
singular (individual). In fact, dejinite and indefinite are the only quantities of
which we ought to hear in Logic ; for it is only as indefinite that particular, it
is only as definite that individual and general, quantities have any (and the
same) logical avail.
" 2°. The revocation of the two Terms of a proposition to their true relation ,-
a proposition being always an equation of its subject and its predicate.
"3o. The consequent reduction of the Conversion of Propositions from three
species to one, — that of Simple Conversion.
" 4°. The reduction of all the General Laws of Categorical Syllogisms to a
Single Canon.
of his doctrine of the Qnantiflcation of the
Predicate: — "Touching the principle of an
explicitly Quantified Predicate, I had, by 1833,
become convinced of the necessity to extend
and correct the logical doctrine upon this
point. In the article on Logic (in the Edin-
burgh Review) first published in 1833, the theory
of Induction there maintained proceeds on
a thorough quantification of the predicate, in
affirmative propositions.
" Before 1840, 1 had, however, become con-
vinced that it was necessary to extend the
principle equally to negatives; for I find, by
academical documents, that in that year, tt
latest, I had publicly taught the unejcolusive
doctrine." — Discussions, p. 650. — Ed.
APPENDIX. 511
" 5°. The evolution from that one canon of all the Species and varieties of
Syllogism.
" 6°. The abrogation of all the Special Laws of Syllogism.
" 7°. A demonstration of the exclusive possibility of Three syllogistic Figures .
and (on new grounds) the scientific and final abolition of the Fourth.
" 8°. A manifestation that Figure is an unessential variation in syllogistic
form ; and the consequent absurdity of Reducing the syllogisms of the other
figures to the first.
" 9°. An enouncement of one Organic Principle for each Figure.
" 1 0°. A determination of the true number of the legitimate Moods ; with
" 1 1°. Their amplification in number (thirty-six) ;
" 12°. Their numerical equality under all the figures; and,
" 13°. Their relative equivalence, or virtual ' identity, throughout every sche-
matic difference.
" 14°. That, in the second and third figures, the extremes holding both the
same relation to the middle term, there is not, as in the first, an opposition and
subordination between a term major and a term minor, mutually containing and
contained, in the counter wholes of Extension and Comprehension.
"16°. Consequently, in the second and third figures, there is no determinate
major and minor premise, and there are two indifferent conclusions ; whereas,
in the frst the premises are determinate, and there is a single proximate con-
clusion.
" 16°. That the third, as the figure in which Comprehension is predominant, is
more appropriate to Induction.
" 1 7°. That the second, as the figure in which Extension is predominant, is
more appropriate to Deduction.
" 18°. That the^rs^, as the figure in which Comprehension and Extension are
in equilibrium, is common to Induction and Deduction, indifferently.
"In the third place, a scheme of Symbolical Notation will be given, wholly
different in principle and perfection from those which have been previously
proposed ; and showing out, in all their old and new applications, the proposi-
tional and syllogistic forms, with even a mechanical simplicity.
"This Essay falls naturally into two parts. There will be contained, — in
the_^rs/, a systematic exposition of the new doctrine itself; in the second, an
historical notice of any occasional anticipations of its several parts which break
out in the writings of previous philosophers.
" Thus, on the new theory, many valid /orms of judgment and reasoning, in
ordinary use, but which the ancient logic continued to ignore, are now openly
recognized as legitimate ; and many relations, which heretofore lay hid, now
come forward into the light. On the one hand, therefore, Logic certainly
becomes more complex. But, on the. other, this increased complexity proves
only to be a higher development. The developed Syllogism is, in effect,
recalled, from multitude and confusion, to order and system. Its laws, ere-
while many, are now few, — we might say one alone, — but thoroughgoing. Tlie
exceptions, formerly so perplexing, have fallen away ; and the once formidable
array of limitary rules has vanished. The science now shines out in the true
character of beauty, — as One at once and Various. Logic thus accomplishes
512
APPENDIX.
its final destination ; for as ' Thrice-greatest Hermes,' speaking in the mind of
Plato, has expressed it, — ' The end of Philosophy is the intuition of Unity.' "
II. — Logic, — Its Postulates.
(November 1848 — See p. 81.)
I. To state explicitly what is thought implicitly. In other words, to deter-
mine what is meant before proceeding to deal with the meaning. Thus in the
proposition Men are animals, we should be allowed to determine whether the
term men means all or some men, — whether the term animals means all or some
animals ; in sliort, to quantify both the subject and predicate of the proposition.
This postulate applies both to "Propositions and to Syllogisms.^
II. Throughout the same Proposition, or Immediate (not mediate) Reason-
ing, to u.se the same words, and combinations of words, to express the same
thought * (that is, in the same Extension and Comprehension), and thus iden-
tity to be presumed.
Thus a particular in one (prejaeent) proposition of an immediate reasoning,
though indefinite, should denote (he same part in the other. This postulate
applies to inference immediate, e. g. Convei-sion-
Predcsignate in same logical unity (proposition or syllogism), in same sense,
both Collective or both Distributive. That one term of a proposition or syllo-
gism should not be used distributively and another collectively.
III. And, e contra, throughout the same logical unity (inunediate reasoning),
to denote and presume denoted the same sense (notion or judgment) by the
same term or terms."
This does not apply to the ditTerent propositions of a Mediate Inference.
IV. (or V.) To leave, if necessary, the thought undetermined, as subjectively
uncertain, but to deal with it only as far as certain or determinable. Thus a
1 See (quoted by Wallis, Logka, p. 291), Ar-
istotle, An. Prior., L. i., c. 33 (I'acius, c. 32, H
2, 3. 4, p. 261), and Ramns (from Downam, In
P. Rami Dialect., L. ii., c 9. p. 410) : What is
utiderstoud to be supplied; IRamus Hial.,Jj,
ii., c. 9. " Si qua [de argumeutationis conse-
qnentia propter crypsin] dubitatio fuerit, ex-
pleiida quae desunt; ampotanda qnas «uper-
i<uitt; et pars qusclib«t in locum redigenda
situ est."] [Cf. rioucquet, Elemrnta Philoso-
phirp Contemptativcr, 5 29, p. 5. Stutgardise,
1778. " Secundum sensum logicum cum omni
teimino Jungendum est signum quantitatis."
— Ed. J
- That words must be used in the same
sense Sec Aristotle, Anal. Prior., L. i., cc. 33.
84, 85. 8«, 37, etc
3 If these postulates (II. and III.) were not
cogent, we could not convert, at least not use
the converted proposition (un!e.ss tlie I. were
cogent, the convntemla would be false). All
man is (an) animal, is converted into Some an-
imal 13 {alt) man. But if the .'ome animal here
were not thought in and limited to the sense
of the convertend, it would be false. So in
the hypothetical proposition, // tlie Chinrse
are Mohammedans, they are (some) infidels ; the
word infidel, unless thought iu a meaning
limited to and true of Mohammedans, is inept.
But if it be so limited, we can (contrary to
the doctrines of the logicians) argue baclc
from the jMisition of the consequent to the
position of the antecedent, and from tlie snb-
lation of the antecedent to the sublation of
the consequent, though false. If not grauted.
Logic is a mere childish play with the vague-
ness and ambiguities of language. fCf Titius,
Arx Cogitandi, C. xii., } 26 — ED.]
APPENDIX. 513
whole may be truly predicable, though we know only the truth of it as a part.
Therefore, we ought to be able to say some at least when we do not know, and
cannot, therefore, say determinately, either that some only or that all is true.
(January 1850.)
III. (or IV.) To be allowed, in an immediate reasoning, to denote, that an-
other part, other, or some, is used in the conclusion, fromwhatwasin the antece-
dent. Inference of Sub-contrariety.
That the some, if not otherwise qualified, means some only, — this by pre-
sumption.
That the Term (Subject, or Predicate) of a Proposition shall be converted
with its quantity unchanged, i. e. in the same extension. This violated, and
violation cause of error and confusion. No per accidens, for the real terms
compared are the quantified terms, and we convert only the terms compared in
the prejacent or convertenda.
That the same terms, apart from the quantity, i, e , in the same comprehen-
sion, should be converted. As before stated, such terms are new and different.
No Contraposition, for contraposition is only true in some cases, and even in
these it is true accidentally, not by conversion, but through contradiction ; i. e., ,
same Comprehension.
That we may see the truth from the necessary validity of the logical process, .
and not infer the validity of the logical process from its accidental truth. Con-
version per accidens, and Contraposition, being thus accidentally true in some -
cases only, are logically inept as not true in all.
To translate out of the complexity, redundance, deficiency, of common lan-
guage into logical simplicity, precision, and integrity.*
(December 1849.)
As Logic considers the form and not the matter, but as the form is only man-
ifested in application to some matter, Logic postulates to employ any matter in.
its examples.
(January 1850.)
That we may be allowed to translate into logical language the rhetorical ex--
pressions of ordinary speech. Thus the Exceptive and Limitative proposi-
tions in which the predicate and subject are predesignated, are to be rendered
into logical simplicity.
(May 1850.)
As Logic is a formal science, and professes to demonstrate by abstract for--
mulae, we should know, therefore, nothing of the notions and their relations
except ex facie of the propositions. This implies the necessity of overtly quan-
tifying the predicate.
1 See p. 512, note 1. — Ed.
65
514 APPENDIX.
in. — Quantification of Predicate, — Ihmediatb Infehence, — Cos-
VERSION, — Opposition.^
(See pp. 172, 185.)
We how proceed to what has been usually treated under the relation of
Propositions, and previously to the matter of Inference altogether, but which I
think it would be more correct to consider as a species of Inference, or Rea-
soning, or Argumentation, than as merely a preparatory doctrine. For in so
far as these relations of Propositions warrant us, one being given, to educe
irom it another, — this is manifestly an inference or reasoning. Why it has
not always been considered in this light is evident. The inference is immedi-
ate ; that is, the conclusion or second proposition is necessitated, directly and
without a medium, by the first. There are only two propositions and two
notions in this species of argumentation ; and the logicians have in general
limited reasoning or inference to a mediate eduction of one proposition out of
the correlation of two others, and have thus always supposed the necessity of
three terms or collated notions.
But they have not only been, with few exceptions, unsystematic in their pro-
cedure, they have all of them (if I am not myself mistaken) been fundamen-
tally erroneous in their relative doctrine-
There are various Immediate Inferences of one proposition from another.
Of these some have been wholly overlooked by the logicians ; whilst what they
teach in regard to those which they do consider, appears to me at variance with
the truth.
1 shall make no previous enumeration of all the possible species of Immedi-
ate Inference ; but shall take them up in this order : I shall consider, 1*, Those
which have been considered by the logicians ; and, 2°, Those which have not
And in treating of the first group, I shall preface what I tliink the true doctrine
by a view of that which you will find in logical books.
The first of these is Conversion. When, in a categorical proposition (for to
this we now limit our consideration), the Subject and Predicate are transposed,
that is, the notion which was previously the subject becomes the predicate, and
the notion which was previously the predicate becomes the subject, the propo-
sition is said to be converted.* The proposition given, and its product, are
together called the judicia conversa, or propositiones conversce, which I shall not
attempt to render into English. The relation itself in which the two judgments
stand, is called concersion, reciprocation, transposition, and sometimes obversion,
(conversio, reciprocatio, transpositio, obversio).
1 Appendix III., from p. 514 to p. 527, was ffiiiiv Kara robs opovs avdvaXiv rt^f/xfyovs,
usually delivered by the author as a Lecture, jutra tov ffvva\ridfufiy. Alexander, /* An.
supplementary to the doctrine of ConTersion Pr. i. c. 4, f. 15 b. See the same in difTerent
as given p. 185. — Ed. word*, by Philoponus (Ammonias),/* An.
2 [Definitions of conversion in general. Pr. i. c. 2, f. 11 b., and copied from him by
'AvTi(rTpo<pri iffnv \aoffrpo<pi\ rts, Philopo- Mafjentinus, In An. Pr., t. 3 b. Cf. Boethius,
nus (or Ammonius), In An. Pr. i. c. 2, f. 11 b. Opera, Introditctio ad Sytlogistnos, p. 574- We-
So Magentinus, In An. Pr. i. c. 2, f. 3 b gelin, in Gregorii Aneponymi Phil. Syniag.
Anonymug, De Syllogismo, f. 42 b. Tlpord- (circa 1260), L. v., c. 12, p. 621. Kicephorus
atws ayri(rrpo<pi} tan Kowwvia Buo irpoTa- Blemmidas, Epit. Log., c. 31, p. 221.]
APPENDIX. 615
The original or^ven proposition Is called the ConversCy or Converted, some-
times the Prcejaceno, Judgment (Judicium, or propositio, conversum, conversa,
prcejacens) ; the other, that into which the first is converted, is called the Con-
vertinff, and sometimes the Subjacent, Judgment (propositio, or Jud. convertens,
subjacens). It would be better to call the former the Convertend (pr. conver-
tenda), the latter the Converse (pr. conversa). This language I shall use.*
Such is the doctrine touching Conveision taught even to the present day.
This in my view is beset with errors ; but all these errors originate in two, as
these two are either the cause or the occasion of every other.
The First cardinal error is, — That the quantities axe not converted with the
quantified terms. For the real terms compared in the Convertend, and which,
of course, ought to reappear without change, except of place, in the Converse,
are not the naked, but the quantified terms. This is evident from the follow-
ing considerations :
1°, The Terms of a Proposition arc only terms as they are terms of relation ;
and the relation here is the relation of comparison.
2°, As the Propositional Terms are terms of comparison, so they are only
compared as Quantities, — quantities relative to each other. An Affirmative
Proposition Is simply the declaration of an equation, a Negative Proposition Is
simply the declaration of a non-equation, of Its terms. To change, therefore,
the quantity of either, or of both Subject and Predicate, is to change their cor-
relation, — the point of comparison ; and to exchange their quantities, if dif-
ferent, would be to invert the terminal interdependence ; that is, to make the
less the greater, and the greater the less.
3°, The Quantity of the Proposition in Conversion remains always the same ;
that is, the absolute quantity of the Converse must be exactly equal to that of
the Convertend. It was only fcom overlooking the quaittlty of the predicate
1 See p. 185. — Ed. or exponens, quite different as used by Logi-
[Xames for the two propositions in Conver- cians, v. Scliegkius, In Arist. Org. 162 (and
sion. above, p. 186.)
I. Name for the two correJative proposi- g) Convertenda, Corvinus, lot. at. Eichter,
tions — Conversa, Twesfen, Lo^ik, § 87, Con- loc. cit.
traposita, Id. ibid. h) Contraponens, Twesten, Ibid.
II. Original, or Given Proposition. i) Prior, Boethius, De Syllog. Categ. L. I. Op-
a) ■^ irporiyovneirrj, rpoKei/xfinn, avTiarpe^o- ' era, p. 588.
liiirq Trp6Tacns — Ct. Strigelius In Me- k) Priiicipium, Darjes, Wa arf rerifa/ejn, } 23i.
landiih. Erot. Dial., L. ii., jS. 581. Ill- Product of Conversion.
^Ain-t<TTpe<povirca irpordtreis, Philoponus, a) V avTicrrpfipovffa. See Strigelius, loe. cit.
(quoted by Wegelin, I. e.) b) Convertens, Subjacens, Scotus, Quastiones,
b) Conversa (= Convertenda) vulgo. Scotus, In An. Prior., i.d,2i,{. 216,(1 passim. Krug,
Quastiones in An. Prior., i q. 12. Corvinus, Logik, § 65, p. 205, and logicians in general.
Instil. Pliil.. i 510. Richter, De Conversione, c) Conversa, Boethius, Opera, IntroU. ad Syll.,
1740. Halae Magdeb. Baumgarten, Lo^ica, pp. 575 <•« .v?., 587 f« .'<?.; Melanchthon, iV-
§ 278. Ulrich,irt.<tit. Log. et Met., ^ 182, p. 188. otemata, L. ii. p. 581, and Strigelius, ad loe.
C) Convertibilis (raro). Micraelius, Lex. Phil., v. Conversio. Nold-
d) Convertens, Micraelius, Lex. Phil. «. Con- ius, Logica Recognita, p. 263, says that the
versio. Twesten, Logik, } 87. Antecedens, first should more probably be called Con-
Scotus, I. c. StrigeJiup, L c. vertibilis, or Convertenda, and the second
e) Prjejacens, Scheibler, Opera Logica De Prop- Conversa.
ositionibus, Pars iij. c. x. p. 479. d) Conversi^m, Twesten, loe. cit.
f ) Exposita, AJdrich, Comp., L. i. c. 2. e) Contrapositum, Id. ibid.
Whately, Logxt^ p. 69. Propositio 'exposita f ) Conclusio, Darjes, Tia ad Veritatem, { 23i
516
APPENDIX.
(the second error to which we shall immediately advert) that two propositions,
exactly equal in quantity, in fact the same proposition, perhaps, transposed,
were called the one universal, the other particular, by exclusive reference to the
quantity of the subject.
4°, Yet was it of no consequence, in a logical point of view, which of the
notions collated were Subject or Predicate ; and their comparison, with the
consequent declaration of their mutual inconclusion or exclusion, that is, of af-
firmation or negation, of no more real difference than the assertions, — London
is four hundred miles distant from Edinburgh, — Edinburgh is four hundred miles
distant from London. In fact, though logicians have been in use to place the
subject first, the predicate last, in their examples of propositions, this is by no
means the case in ordinary language, where, indeed, it is frequently even diffi-
cult to ascertain which is the determining and which the determined notion.
Out of logical books, the predicate is found almost as frequently before as after
the subject, and this in all languages. You recollect the first words of the
First Olympiad of Pindar, "KfjiaTov yiev vSup, " Best is water ; " and the Vulgate
(I forget how it is rendered in our English translation) has, " Magna est Ver-
itas, et praevalebit."^ Alluding to the Bible, let us turn up any Concordance
under any adjective title, and we shall obtain abundant proof of the fact. As
the adjective great, magtius, has last occurred, let us refer to Cruden under that
simple title. Here, in glancing it over, I find — " Great is the wrath of the
Lord — Great is the Lord and greatly to be praised — Great is our God —
Great are thy works — Great is the Holy One of Israel — Great shall be the
peace of thy children — Great is thy faithfulness — Great is Diana of the
Ephesians — Great is my boldness — Great is my glorying — Great is the
mystery of godlines?," etc.
The line of Juvenal,
" Nobilitas sola est atque unica virtus,"
is a good instance of the predicate being placed first.
The Second cardinal error of the logicians is, the not considering that the
Predicate has always a quantity in thought, as much as the Subject; although
this quantity be frequently not explicitly enounced, as unnecessary in the com-
mon employment of language ; for the determining notion or predicate being
always thought as at least adequate to, or coextensive with, the subject or de-
termined notion, it is seldom necessary to express this, and language tends ever
to elide what may safely be omitted. But this necessity recurs the moment
that, by conversion, the predicate becomes the subject of the proposition ; and
1o omit its formal statement is to degrade Logic from the science of the neces-
sities of thought, to an idle subsidiary of the ambiguities of speech. An un-
biassed consideration of_the subject will, I am confident, convince you that
tliis view is correct.
1°, Tliat the predicate is as extensive as the subject is easily shown. Take
the proposition, — All animal is man, or. All animals are men. This we arc
1 III. Esdras ir. 41 : " Magna est Veritas et ir. 41), " Great is truth, aud mighty above all
pnevalet " In the iCuglish rereiou (I. Esdras things." — £d.
APPENDIX. 617
conscious is absurd, though we maJce the notion man or men as wide as possible ;
for it does not mend the matter to say, — All animal is all man, or, All animals
are all men. We feel it to be equally absurd as if we said, — All man is all
animal, or, All men are all animals. Here we are aware that the subject and
predicate cannot be made coextensive. If we would get rid of the absurdity,
we bring the two notions into coextension, by restricting the wider. If we say,
— Man is animal (^Homo est animal), we think, though we do not overtly
enounce it, AU man is animal. And what do we mean here by animal ? We
do not think, — All, but Some, animal. And then we can make this indiffer-
ently either subject or predicate. AVe can think, — we can say, Some animal
ts man, that is. Some or All Man ; and, e converso, — J\Ia7i (some or all) is
animal, viz., some animal.
It thus appears that there is a necessity in all cases for thinking the predicate,
at least, as extensive as the subject Whether it be absolutely, that is, out of
relation, more extensive, is generally of no consequence ; and hence the
common reticence of common language, which never expresses more than
can be understood, — which always, in fact, for the sake of brevity, strains at
ellipsis.
2'^, But, in fact, ordinary language quantifies the Predicate so often as this
determination becomes of the smallest import. This it does directly, by adding
all, some, or their equivalent predesignations, to the predicate ; or it accom-
pUshes the same end indirectly, in an exceptive or limitative form.
») Directly, — as Peter, John, James, etc., are all the Apostles — Mercury,
Venus, etc., are all the planets.
b) But this is more frequently accomplished indirectly, by the equipollent
forms o? Limitation or Inclusion, and Exception.^
For example, by the limitative designations, alone or only, we say, — God
alone is good, which is equivalent to saying, — God is all good, that is, God is
all that is good ; Virtue is the only nobility, that is. Virtue is all noble, that is, all
that is nohle.^ The symbols of the Catholic and Protestant divisions of Chris-
1 By the ]o},'icians this is called simply Ex- subject alone. As, Man alone philosophizes
elusion, and the particles, tantu7n, etc., panic- (though not all do). The dog alone barks, or,
ulfr, fxclusivrr. This, I think, is inaccurate; dogs alone bark (though some do not). ' Man
for it is inclusion, limited by an exclusion, only is mtional, or. No animal but man is ra-
that is meant. — [See Seheibler, Opera Logica, tional. Nothing but rational is risible. Of ma-
1*. iii. C. vii. tit. 3, p. 457 et seq.] terial things there is nothing living {but) not
2 (February 1850.) Ou the Indirect Predes- organized, and nothing organized not living.
ignation of the Predicate by what are called God alone is to be ivorskipped. God is th*
the Exclusive and Exctptive particles. single, — sole object of vjorship. Some men only
Names of the particles. are elect.
Latin, — unus, vnicus, unice ; solus, solum, II. Annexed to the Predicate, they limit
solummodo, tantum, tantummodo; duntaxat ; the subject to the predicate, but do not define
pracise; adequate. Nihil pr<p.ter, — prceterquam, its quantity, or exclude from it other sub-
— ni nisi non. jects. As, Peter only plays. The sacraments
English, — one, only, alone, exclusively, pre- are only two. John drinks only water,
cisely. just, sole, solely, nothing but, not except, III. Sometimes the particles sole, sole!-;
not beyond. single, alone, only, etc., are annexed to t..?
I. These particles annexed to the Subject Predicate as a predesignation tantamount {»,
prcdesignate the Predicate universally, or to all. As, God is the single, — one, — alone. —
its whole extent, denying its j)articularity or only, — exclusive, — adequate, object of worship.
indefinitude, and definitely limiting it to the On the relation of Exclusive propositions
518
APPENDIX.
tianitj may afford us a logical illustration of the point. Tlie Catholics say,-^
Faith, Hope, and Charity alone justify ; that is, the three heavenly virtues together
are all Justifying, that is, all that justifies ; omne juslifcans, justum faciens. The
Protestants say, — Faith alone justifies ; that is, Faith, which they hold to com-
prise the other two virtues, is all justifying, that is, all that justifies ; omne justi-
ficans. In either case, if we translate the watchwords into logical simplicity,
the predicate appears predesignated.
Of animals man alone is rational ; that is, Man is all rational animal. WheU is
rational is alone or only risible ; that is, All rational is all risible, etc.
I now pass on to the Exceptive Form. To take the motto overhead, — "On
earth there is nothing great but man." What does this mean ? It means,
Man — is — all earthly great. — Homo — est — omne magnum terrestre. And the
second clause — " In man there is nothing great but mind " — in like manner
gives as its logical equipollent — Mind — is — all humanly great, that is, all that
is great in man. (J/e/is est omne magnvm hwnanum.y
to those in which the predicate is predesig-
nated, sec Titius, Ars Cogitandi, c. vi. H 66,
67- Hollman, Philoaophia Ralionalis, J 475.
Kreil, Handbwh der Lo^ik. S 62. Derodon,
Logica Restituta, De Enunciationey C. v. p. 569
ft $eq. Keckermann, Systema Logica, lib. iii.,
C. 11. Opera, t. i. p. 763.
The doctrine held by the logicians as to the
exdusum pradieatum, exdusum 3ubjectuvi, and
exclusum signum, is erroneous. See Scheibler,
Opera Logica, P. iii. c. vii. tit. 3, p. 457 et Sfq.
Jac. Thomasius, Erutem. Lo^., c xxx. p. 67 ft
teq. [Cf. Fonseca, Inftlt. Dial , L. III. c. 23.
For a detailed exposition of this doctrine by
Scheibler, see below, note 1. — Ed.]
1 Vide Scheibler, Opera Logica, P. iii. c. vii.
pp. 458, 460, where his exnnii)le.«, with the ex-
position of the Logicians, may be well con-
trasted with mine.
[Scheibler, after referrin/f to the Porra Logi-
etdia of the schoolmen, as containing a pro-
posed.supplement of the doctrines of Aris-
totle, proceeds to expound the Propositioius
ExpnnibiU.% of those treatises. " Exclusiva
enunciatio est, quic habet particulain exciu-
sivam, ut. Solus homo est rationalis. . . .
Porro excluslvae ennnciationos sunt duplicis
generis. Alia; sunt exclusivae prsedicati : aliae
exclusive subjecti ; hoc est, in aliis particula
exclusiva excludit a subjecto, in aliis excludit
a pra:dicato, velnti h«c propositio exclusiva
est; Deus taatum est immortalis. Estque ex-
clusiva a subjecto, hoc sensu, Dens tantum, et
non homo vel lapis, etc Omnes
propositiones exclusivie ambiguae sunt, si
habeant particulam exclusivam. post snbjec-
tum propositionis, ante vinculum, ut erat in
proposito exeroplo. Carent autem propositi-
ones exclusivse ilia ambiguitate, si vel exclu-
Hva particula, ponatur ante subjectum prop-
ositionis. vel etiam seqnatnr copnlam. Ibl
enim indicatur esse propositio exclusiva snb-
jecti, ut, solus homn discurrit Hie autem in-
dicatur, esse propositio exclusiva pi-aedicat^
nt, Sacramenta Nofi Testaiiienii suvt tatttuin
duo. Praniicamtnta tantum drcem.'-''
Scheibler then proceeds to give the follow-
ing general and special rules of Exclusion :
"I. Generaliter tenendum est, quod aliter
sini expon-rulft txclusira a pradicalo, el alitet
exclusifa a subjecto.
'* II. Exclusiva propo^tio non exdudit toncom-
itantia
"III. Otnnis exclusiva rtsolcititr in duos srm-
plicex, alteram nffinnatam, alteram negatam.
Atquc hoc est quod vulgo dicitur, quod
omnis exclusiva sit hypothetica. Hypotb^tica
enim propositio est quae includit duas alias in
virtute, vel dispositione sua. Veluti haec.
Solus homo est ral'onalis, squivalet bis dua>
bus, Homo est rationalis, et quod non est homo,
non est rationale. £t in specie, Bestia non rsl
rationalis. Plnnta non est rationalis. ....
Atque hse du;c propositiones vocautur ejpo-
nentes, sicut propositio exclusiva dicitur rx-
ponibilis.
'' Speciales antem regnlie explicandi excln-
sivas sunt octo: sicut et octo sunt genera
locutionum exclusivarum.
" I. Propositio f-xclusiva univrrsalis a_fffrtna~
tiva, citjus signum non negotur, ut, Tantum
omnis homo turrit, exponitur sic, Omnis homo
currit, et nihil aliud ab hotnine ctirrit. Vocari
solet luec expositio Pater, quia prior ejus
pars est universalis affirmativa, quod notnt
A. Et, alterae pars est universalis negativa.
quod indicat in posteriori syllaba litera E
"II. Propositio particularism vel indeftnita of-
firmativa, in qua signum non negatur, ut Tan-
tum homo currit, exponitur sic, Homo ctmit, tl
APPENDIX. 519
We ought, indeed, as a corollary of the postulate already stated, to require
to be allowed to translate into equivalent logical terms the rhetorical enounce-
ment of common speech. We should not do as the logicians have been wont,
— introduce and deal with these in their grammatical integrity ; for this would
be to swell out and deform our science with mere grammatical accidents ; and
to such fortuitous accrescences the formidable volume, especially of the older
Logics, is mainly owing. In fact, a large proportion of the scholastic system is
merely grammatical.
3o, The whole doctrine of the non-quantification of the predicate is onlj'
another example of the passive sequacity of the logicians. They follow obedi-
ently in the footsteps of their great master. We owe this doctrine and its preva-
lence to the precept and authority of Aristotle. He prohibits once and again the
annexation of the universal predesignation to the predicate. For why, he says,
such predesignation would render the proposition absurd; giving as his only exam-
ple and proof of all this, the judgment — All man is all animal. This, however,
is only valid as a refutation of the ridiculous doctrine, held by no one, that any
predicate may be universally quantified ; for, to employ his own example, what
absurdity is there in saying that some animal is all man ! Yet this nonsense
(be it spoken with all reverence of the Stagirite) has imposed the precept on
the systems of Logic down to the present day. Nevertheless, if could be shown
by a cloud of instances from the Aristotellc writings themselves, that this rule is
invalid ; nay, Aristotle's own doctrine of Induction, which is far more correct
than that usually taught, praceeds upon the silent abolition of the erroneous
canon. The doctrine of the logicians is, therefore, founded on a blunder;
which is only doubled by the usual avennent that the predicate, in what are
technicall}' called reciprocal propositions, is taken universally vi materia; and
not vi formce.
But, 4°, The non-quantification of the predicate in thought is given up by
the logicians themselves, but only in certain cases where they were forced to
admit, and to the amount which they could not possibly deny. The predicate,
nihil aliud ab homine currit. Vocatur hacc ex- aliquid aliiid ab homine non curril, vocatur
positio XisK. Fecit.
"III. Propositio exdttsiva, in qua signum non " VII. Exdusica, in qua signum negatur, ex-
negatur, universalis negativa, ut, TantuTn nuUus isiens particularis qffirmativa, ut, Non tantuni
homo currit, exi)Onitur sic, NuUui homo currit. aliquis homo currit, expositur sic, Aliquis homo
tt quodlibet aliud ab homine currit, vocatur Te- currit, aliquia aliud ab homine currit, vocatur
WAX. I'lLOS.
"IV. Exrlusivacujus signum non negatur par- "VIII. Negativa particularis exclusivm prop-
'.ieularis vet indefinita negativa, ut, Tantum homo ositiones, cvjus signum negatur, ut, Non tantuni
non cnrrit, exponitur sic, Homo non currit, aliqais homo non ctirrit, exponitur sic, Aliquis
tt quodlibet cUiutl ab homine currit, vocatur homo non currit, et aliquid aliud ab homine non
STORAX. currit, vocatur NOBIS.
"V. Exclusiva, in qua signum negatur, affir- '• Differentia autem propositionis exclusivas
mativa et universalis, ut, Non tantum omnis et exceptivae est evidens. Nempe exclusiva
homo currit, exponitur sic, Omnis homo currit, praedicatum vendicat uni subjecto, aut a sub-
(t aliquod aliud ab homine currit, vocatur jecto excludit alia praedicata, ut, Solus Devs
Canos. bonus est. Exceptiva autem statuit universale
*^ y I. In qua signum negatur, txistensuniver- subjectum, iudicatque aliquid contineri sub
salis affirmativa, ut, Non tantum nullus homo isto universali, de quo nou dicatur prasdica-
currit, sic exponitur, Nullus homo currit, et turn, ut, Omne anim<d est irrationals, preeter
hominem.''^ — ED.]
620
APPENDIX.
they confess, is quantified by particularity in affirmative, by universality in nega-
tive, propositions. But why the quantification, formal quantification, should
be thus restricted in thought, they furnish us with no valid reason.
To these two errors I might perhaps add, as a third, the confusion and per-
plexity arising from the attempt of Aristotle and the logicians to deal with in-
definite (or, as I would call them, indesignale) terms, instead of treating them
merely as verbal ellipses, to be filled up in the expression before being logically
considered ; and I might also add, as a fourth, the additional complexity and
perplexity introduced into the science by viewing propositions, like>vise, as
affected by the four or six modalities. But to these I shall not advert.
These are the two principal errors which have involved our systems of Lc^ic
in confusion, and prevented their evolution in simplicity, harmony, and com-
pleteness ; — which have condemned them to bits and fragments of the science,
and for these bits and fragments have made a load of rules and exceptions
indispensable, to avoid falling Into frequent and manifest absurdity. It was In
reference to these two errors chiefly that I formerly gave aou as a self-evident
Postulate of Logic — " Explicitly to state what hats been implicitly thought ; "
in other words, that before dealing logically with a proposition, we are entitled
to undei-stand it ; that Is, to ascertain and to enounce its meaning. This quali-
fication of the predicate of a judgment Is, Indeed, only the beginning of the
application of the Postulate ; but we shall find that at every step it enables us
to cast away, as useless, a multitude of canons, which at once disgust the student,
and, if not the causes, are at least the signs, of imperfection in the science.
I venture, then, to assert that there is only one species of Convoreion, and that
one thorough-going and self-sufficient. I mean Pure, or Simple Conversion.
The other species — all are admitted to be neither thorough-going nor self-
sufficient — they are In fact only other logical processes, accidentally combined
with a transposition of the subject and predicate. The conversio per accidens
of Boetnlus, as an ampliative operation, has no logical existence ; it is material
and precarious, and has righteously been allowed to drop out of science. It
is now merely a historical curiosity. As a Restrictive operation, in which re-
lation alone It still stands in our systems, it Is either merely fortuitous, or
merely possible through a logical process quite distinct from Conversion ; I
mean that of Restriction or Subalternatlon, which will be soon explained.
Converaio per contrapositionem is a change of terms, — a substitution of new
elements, and only holds through contradiction,^ being just as good without as
I [See Aristotle, Topica, L. ii. c. 8. Scotus,
Bannes, Mendoza, silently following each
other, have held that contraposition is only
mediate, inflnitation, requiring Constantia,
etc. Wholly wrong. See Arringa. Cursus
PMlnsophicvs, D. II s. 4. p. 18. "Observan-
dum est prwdictas C(>n8e(iueiitias (per contra-
positionem) malas esse et instiibilcB, nisi r.c-
cesscrit alia jiropositio in antecedenii qua;
impartit existentiam subjecti consequeiitis.
Tunc enim firma erit consequentia, e. s-
Omnis homo est albus et non alburn est, er^o
otnne non album est non homo. Alioquin si
eonstantiam illam uon posueris in antecedenti,
instabitur illi consequentia; iu eveutu, in quo
nihil sit non album, et omnis homosit albus.''
Baunes, Instit. Min. Dial. L. vi. c. 2, p. 590.
— Ed.]
Rule for Finite Prejacents given.
With the single exception of E n E ( A n A),
the other seven propositions may be converted
by Counterposifion under tlic following rule,
— ' Let the terms be inlinitated and transposed,
the predesignations remaining as before '
With the two additional e.Kceptions of the
two convertible propositions, A f I, and I f
APPENDIX.
521
with conversion. The Contingent Conversion of the lower Greeks^ is not. a
conversion, — is not a logical process at all, and has been worthily ignored by
the Latin world. But let us now proceed to see that Simple Conversion, as I
have asserted, is thorough-going and all-sufficient. Let us try it in all the
eiglit varieties of categorical propositions. But I shall leave this explication to
yourselves, and in the examination will call for a statement of the simple con-
version, as applied to all the eight propositional forms.
It thus appears that this one method of conversion has every advantage
over those of the logicians. 1°, It is Natural ; 2°, It is Imperative ; 3°, It is
Simple ; 4°, It is Direct ; 5°, It is Precise ; 6°, It is thorough-going : Whereas
their processes are — 1°, Unnatural; 2°, Precarious; 3°, Complex; 4°, Cir-
cuitous ; 5°, Confused ; 6°, Inadequate : breaking down in each and all of
their species. The Greek Logicians, subsequent to Aristotle, have well and
truly said, a.vTi<TTpo<pT] i<mv i(To<TTpo<l>^ ns, " omnis conversio est aequiversio; " * that
is, all conversion is a conversion of equal into equal ; and had they attended
to this principle, they would have developed conversion in its true unity and
simplicity. They would have considered, 1°, That the absolute quantity of
A, the inflnitated propositions hold good
without the transposition of the terms.
Rule for Iiiflulte Prejacents given.
With the single exception of n I f n I (nE
= u = uE being impossible), the other six
propositions may be converted by Counter-
position under the following rule, — ' Let the
terms be unintinitated and transposed, the
predesignations remaining as before.'
Contraposition is not explicitly evolved by
Aristotle in Prior Analytics, but is evolved
from his Topics, L. ii. cc. 1, 8, alibi. De Inter'
pretatione, c. 14. See Conimbricenses, In Arist.
Dial., An. Prior., L. i. q. i. p. 271. Bannes,
Instit. Minoris Dialectics, L. v. c. 2, p. 532.
Burgersdicius, Instit. Log- L. i. c. 32.
First explicitly enounced by Averroes, ac-
cording to Molinaeus (Elementa Logica, L. i.
c. 4, p. 54). 1 cannot tlnd any notice of it in
Averroes. Ue ignores it, name and thing.
It is in Anonymus, De Syllogismn, f. 42 b., in
Kicephorus Blemmidas, Epit. Log., c. xxxi.
p. 222 ; but long before him Boethius has all
the kinds of Conversion, — Simplex, Per Acci-
dens, et Per Opposilionem (Introdnctio ad SyUo-
gismos, p. 576), what he calls Per Contraposi-
tionem [De Syllogismo Calegorico, L. i. 589).
Is he the inventor of the name? It seems so.
Long before Boethius, Apuleius (in second
century) has it as one of the five species of
Conversion, but gives it no name — only de-
scriptive; sec De HabitwI. Doct. Plat., L. iii. p.
33. Alexander, In An. Pr.. i. c. 2. f. 10 a, has
it as of propositions, not of terms, which is
conversion absolutely. Vide I'hiloponus. In
An. Pr., I. f. 12 a. By tliem called ai/rto-TpofpT;
oliv OLfT i^(<Tfi. So Magentinus, In An. Prior ,
i. 2, f.3b.
That Contraposition is not properly Con
version — (this being a species of consequence)
— an aequipoUence of propositions, not a con-
version of their terms.
Noldius, Logica Recognita, c. xii. p. 299
Crakanthorpe, Logica, L. iii. c. 10, p. 180.
Bannes, Instit. Min. Dial., L. v. c. 2, p. 530.
Eustachius, Summa Pkilosopkice, Logica, P. II
tract, i. q. 3, p. 104. Ilerbart, Lehrbuch der
Logik, p. 78. Scotus, Quastiones, In An. Prior.,
L. i. q. lo, f. 258 b. Chauvin, v. Conversio.
Isendoorn, Cursus Logicus, p. 308.
That Contraposition is useless and perplex-
ing. See Chauvin, v. Conversio. Arriaga,
Cursus, Philosopliicus, p. 18. Titius, Ars Cogi-
tandi, c. viii. § 19 et seq. D"Abra de Kaconis,
Tot. Phil. Tract., Logica, ii. qu. 4, p. 315.
Bannes, Instit. Min. Dial., p. 529]
1 [Blemmidas.] [Epitoine Logica, c. 31, p.
222. The following extract will explain the
nature of this conversion. 'H S' iu Trpora-
aeai yivofj.fi/y) auicTTpo^^, r] T'})*' fieu ra^iu
Twi/ '6pwv (pvKarrfi, rhv avThu rripovaa kut-
riyopovfj,(vov koI rhv avThv vwoKfifievou '
ix6vtiv 8* TTjc 'iroi6T7YTa fiSTu^aWfi, iroiovcra
T7)j/ airo<paTiKi]v ir^ioTeaiv KaracpaTiKTqv, koI
Kara<pa,riicr}v a.ito(pariKi)v. Ko2 Ae-yerai
oSttj ^j/SexoMfVij a.vTi<TTpo<pi], ws ^nl ixoinjs
T^y ^fSexOiUfVes KAtjs (TwitTTafJifvi) ' oiov,
Tts iv^pojiroi Koverai, tis w^pKinros ov \ov-
T]Tcu' avTT) S' ovK tiu €^7) Kvp'iws afTiarpocpr}.
This so-called contingfnt conversion is in fact
nothing more than the assertion, ippeatcd by
many Latin logicians, that in contingent mat-
ter subcontrary propositions are both tru«.
— Kd.]
2 See p. 515. — Ed.
6G
522
APPENDIX.
the propositioi>, be it convertend or converse, remains always identicjd ; 2',
That the several quantities of the t-ollated notions remain always identical, tho
whole change being the transposition of the (juantified notion, which was in the
subject place, into the place of predicate, and tnce versa.
Aristotle and the logicians were, therefore, wrong ; 1°, In not considering
the proposition simply as the complement, that is, as the etjuation or non-equa-
tion, of two compared notions, but, on the contrary, considering it as de-
termined in its quantity by one of these notions more than by the other. 2°,
They were wrong in according too great an importance to the notions con-
sidered as propositional terms, that is, as subject and predicate, independently
of the import of these notions in themselves. 3°, They were wiong in ac-
cording too preponderant a weight to one of these terms over the other; but
differently in different parts of the system. For they v.ore wrong, in the doc-
trine of Judgment, in allowing the quantity of the proposition to be determined
exclusively by the quantity of the subject term ; whereas they were wrong, as
we shall see, in the doctrine of Reasoning, in considering a syllc^sm as ex-
clusively relative to the quantity of the predicate (extension). So mui;h for
the theory of Conversion. Before concluding, I have, however, to observe, as
a correction of the prevalent ambiguity and vacillation, that the tw'o oroposi-
tions of the process together might be called the coiwertenl or converting (pro-
positiones convertentes) ; and whilst of these the original proposition is named
the convertend (propositio convertenda), its product would obtain the title of
converse, converted (propositio conversa)}
The other species of Immediate Inference will not detain us long. Of these,
there are two noticed by the logicians.
The first of these, Equipollence (cequipollentia), or, as I would term it. Double
Negation, is deserving of bare mention. It is of mere grammatical relevancy.
The negation of a negation is tantamount to an affirmation, li is not not-A, is
manifestly only a roundabout way of saying B is A ; and, vice versa, we may
express a position, if we perversely choose, by sublating a sublation. The
immediate inference of Equipollence is thus merely the grammatical translation
of an affirmation into a double negation, or of a double negation into an
affirmation. Non-nxiUus and non-nemo, for example, are merely other gram-
matical expressions for aliquis or quidam. So Nonnihil, Nonnunquam, Nonnus-
quam, etc.
The Latin tongue is almost peculiar among languages for such double negjt-
tives to express an affirmative. Of course the few which^ have found their place
in Lofflc, instead of being despised or relegated to Grammar, liave"beeii fondly
commented on by the ingenuity of tbc scholastic logicians. In English, some
authors are fond of this inilirect and idle way of speaking ; they prefer saying
— "'I entertain a not unfavorable opinion of such a one," to saying directly, I
entertain of him a favorable opinion. Neglecting this, I pass on to
The third sj)ecics of Immediate Inference, notii;ed by tlie logicians. This
they call Siibalternation, but it may be more unambiguously styled Restrictipn.
If I have £100 at my credit in the bank, it is evident that I may draw for £5 or
£lO. In like manner, if I can say unexclusively that all men are aninutls, I can
1 Sec p. 185. — Ed.
APPENDIX. 523
say restrictively, that negroes or any other fraction of mankind are animals. This
restriction is Bilateral, when we restrict both subject and predicate, as :
AU Triangle is all trilateral. All rational is all risible.
.'.Some triangle is some trilateral. .■.Some rational is some risible.
It is Unilateral, by restricting the omnitude or universality either of the Subject
or of the Predicate.
Of the Subject —
Of the Predicate, as-
AH man is some animal ;
.Some man is some animal.
Some animal is all risible ;
.Some animal is some risible.
It has not been noticed by the logicians, that there is only an inference by
this process, if the some in the inferred proposition means some at least, that is,
some not exclusive of all ; for if we think by the some, some only, that is, some,
not all, so far from there being any competent inference, there is in fact a real
opposition. The logicians, therefore, to vindicate their doctrine of the Opposi-
tion of Subalternation, ought to have declared that the some was here in the
sense of .tome only ; and to vindicate their doctrine of the Inference of Subal-
ternation, they ought, in like manner, to have declared, that the some was here
taken in the counter sense of some at least. It could easily be shown that
the errors of the logicians in regard to Opposition are not to be attributed to
Aristotle.
Before leaving this process, it may be proper to observe that we might well
call its two propositions together the restringent or restrictive (propositiones
restringentes vel restrict ivce) ; the given proposition might be called the restrin~
gend (propositio restringenda), and the product the restrict or restricted (propo-
sitio restricta).
So much for the species of Immediate Inference recognized by the logicians.
There is, however, a kind of immediate inference overlooked by logical
writers. I have formerly noticed that they enumerate (among the species of
Opposition) Subcontrariety (subcontrarietas, vTr€vavTi6ri\s), to wit, — some is,
some is not ; but that this is not in fact an opposition at all (as in truth neither
is Subalternation In a certain sense). Subcontrariety, in like manner. Is with
them not an opposition between two partial somes, but between different and
different; in fact, no opposition at all. But if they are thus all. wrong by
commission, they are doubly wrong by omission, for they overlook the Immediate
Inference which the relation of propositions in Subcontrariety affords. This,
however. Is sufficiently manifest. If I can say. All men are some animals, or
Some animals are all men, I am thereby entitled to say, — All men are not some
animals, or Some animals are not .some men. Of course here the some In the
inferred propositions means some other, as in the original proposition, some
ordy ; but the inference Is perfectly legitimate, being merely a necessary
explication of the thought; for, inasmuch as I think and say that all men are
524
APPENDIX.
some animals, I can think and say that they are some animals only, which
implies that they are a certain some, and not any other animals.^ This infer-
ence is thus not only to some others indefinitely, but to all others definitely. It
is further either affirmative from a negative antecedent, or negative from an
affirmative. Finally, it Is not bilateral, as not of subject and predicate at once;
but it Is unilateral, either of the subject or of the predicate. This Inference
of Subcontrarlety I would call Integration, because the mind here tends to
determine all the parts of a whole, whereof a part only has been given. The
two propositions together might be called the integral or integrant (propositiones
intcgrales vel integrantes). The given proposition would be styled the integrand
(propositio integranda) ; and the product, the integrate (proposUio integrata)}
I may refer you, for various observations on the Quantification of the Predi-
cate, to the collection published under the title, Discussions on Philosophy and
Literature.
The grand general or dominant result of the doctrine on which I have
already partially touched, but which I will now explain consecutively and more
in detail, is as follows : — Touching Propositions, — Subject and Predicate ; —
touching Syllogisms, — In Categoricals, Major and Minor Tei-ms, Major and
Minor Premises, Figures First, Second, Third, Fourth, and even what I call
No Figure, are all made convertible with each other, and all conversion re-
duced to a simple etjuation ; whilst in Hypothetlcals, both the species (viz.,
Conjunctive and Disjunctive reasonings) are shown to be forms not of mediate
argumentation at all, but merely complex varieties of the immediate inference
of Restriction or Subalternation, and are relieved of a load of perversions,
limitations, exceptions, and rules. The differences of Quantity and Quality,
etc., thus alone remain ; and by these exclusively are Terms, Propositions, and
Syllogisms foimally distinguished. Quantity and Quality combined constitute
the only i-eal discrimination of Syllogistic Mood. Syllogistic Figure vanishes,
with Its perplexing apparatus of special rules ; and even the General Laws of
Syllogism proper are reduced to a single compendious canon.
This doctrine is founded on the postulate of Logic : — To state In language
what is efficient in thought ; in other woixls, Before proceeding to deal logically
with any proposition or syllogism, we must be allowed to determine and express
what it means.
First, then, in regard to Propositions : In a proposition, the two terms, the
Subject and Predicate, have each their quantity in thought This quantity is
not always expressed in language, for lariguage tends always to abbreviation ;
but it is always understood. For example, in the proposition, Men are animals,
what do we mean ? We do not mean that some men, to the exclusion of others,
1 If we gay some animal is all man, and
fome animal is not any man. — in that case, we
<nu8t hold some as meaaiug some only. We
ir.uy have a mediate syllogism on it, as :
Somr; animnU are aU nten ;
Some aniinob are not any man :
Xher^ort, tome atunivfk art not souie animals.
2 Mem. Immediate inference of Contradic-
tion omitted. Also of Relation, which would
come under Equipollence. [For Tabular
Schemes of Prepositional Forms, and of
their Mutual Relations, see pp. 629, 630. -»
Ed.]
APPENDIX. 525
are animals, but we use the abbreviated expression 7n«n for the thought aZZ Tnen.
Logic, therefore, in virtue of its postulate, warrants, nay requires^ us to state
this explicitly. Let ais, therefore, overtly quantify the subject, and say, All
men are animals. So far we have dealt with the proposition, — we have quan-
tified in language the subject, as it was quantified in thought.
But the predicate still remains. We have said — All men are animals. But
what do we mean hy animals? Do we mean aZ^ animals, ov some animals f
Not the former ; for dogs, horses, oxen, etc., are animals, as well as men ; and
dogs, horses, oxen, etc., are not men. Men, therefore, are animals, but exclu-
sively of dogs, horses, oxen, etc. All men, therefore, are not equivalent to all
animals ; that is, we cannot say, as we cannot think, that all men are all ani-
mals. But we can say, for in thought we do affirm, that all men are some animals.
But if we can say, as we do think, that all men are some animals, we can, on
the other hand, likewise say, as we do think, that some animals are all men.
If this be true, it is a matter of indifference, in a logical point of view
(whatever it may be in a rhetorical), which of the two terms be made the
subject or predicate of the proposition ; and whichsoever term is made the
subject in the first instance, may, in the second, be converted into the predi-
cate ; and whichsoever term is made the predicate in the first instance, may, in
the second, be converted into the subject
From this it follows —
1°, That a proposition is simply an equation, an identification, a bringing
into congruence, of two notions in respect to their Extension. I say, in re-
spect to their Extension, for It Is this quantity alone which admits of ampliation
or restriction, the Comprehension of a notion remaining always the same,
being always taken at its full amount.
2*, The total quantity of the proposition to be converted, and the total
quantity of the proposition the product of the conversion, is always one and
the same. In this unexcluslve point of view, all conversion is merely simple con-
version ; and the distinction of a conversion, as it is called, hy, accident, arises
only from the partial view of the logicians, who have looked merely to the
quantity of the subject. They, accordingly, denominated a proposition univer-
sal or particular, as Its subject merely was (quantified by the predeslgnation
some or all ; and where a proposition hke, All men are animals (In thought,
some animals), was converted into the proposition, Some animals are men (In
thought, all men), they erroneously supposed that It lost quantity, was restricted,
and became a particular proposition.
It can hardly be said that the logicians contemplated the reconversion of
such a proposition as the preceding; for they did not (or rarely) give the name
of conversio per accidens to the case In which the proposition, on their theory,
was turned from a particular into a universal, as when we reconvert the prop-
osition. Some animals are men, Into the proposition, All men are animals.'^ They
1 See above, p. 186. — Ed. [A mistake by For Aristotle uses the terms universal, and
logicians in general, that partial conversion, partial conversion^ simply to express whether
^M jtis'pcj, is the mere synonym of per awiVenj, the convertens is a universal or particular
and that the former is so used by Aristotle, proposition. See § 4 of the chapter on Con-
See Vallius, Logica, t. ii. 1 t. q. i. c. 2, p. 32. version (An. Prior., i. 2), where particular af
h
52G APPENDIX.
Kkcwisc neglected such affirmative propositions as Iiad in thought both subjecx
and predicate quantified to their whole extent; ?cS, AH triangular Jigure is trilate-
ral, that is, if expressed iis understood, All trkintju'ar is all trilateral figure^ —
AH rational is risible, that is, if explicitly enounced, All ralional is all rmhle
animals. Aristotle, and subsequent logicians, had indeed frequently to do with
propositions in which the predicate was taken in its full extension. In these
the logicians — but, be it observed, not Aristotle — attempted to remedy the
imperfection of the Aristotelic doctrine, which did not allow the quantification
of the predicate to be taken logically or formally into account in affirmative
propositions, by asserting that in the obnoxious cases the predicate was dis-
tributed, that is, fully quantified, in virtue of the matter, and not in virtue of
the form (^vi materia, non ralione formce). But this is altogether erroneous.
For in thought we generally do, nay, often must, fully quantify the predicate.
In our logical conversion, in fact, of a proposition like All men are animals, —
some animals, we must formally retain in thought, for we cannot formally
al)olish, the universal quantification of the predicate. We, accordingly, must
formally allow the proposition thus obtained, Some animals we all men.
The error of the logicians is further shown by our most naked logical nota-
tion ; for it is quite as easy and quite as natural to quantify A, B, or C, as pre-
dicate, as to quantify A, B, or C, as subject. Thus, All B is some A 5 Some A
is all B.
A,
:B
I may here also animadvert on the counter defect, the counter error, of the
logicians, in their doctrine of Negative Propositions. In negative propositions
they say the predicate is always distributed, — always taken in its full exten-
sion. Now this is altogether untenable. For we always can, and frequently
do, think the predicate of negative propositions as only partially excluded from
the sphere of the subject. For example, we can think, as our naked diagrams
can show, — All men are not some animals, that is, not irrational animals. In
point of fact, so often as we think a subject as partially included within the
sphere of a predicate, co ipso we think it as partially, that is, particularly,
excluded therefrom. Logicians are, therefore, altogether at fault in their
doctrine, that the predicate is always distributed, t. «., always universal, in
negative propositions.^
firmatives arc said to be necessarily con-
verted, 4v /ut'pfi.
Conversio per acculrns is in two forms differ-
ently defliied by different logicians. Tlie first
by Doetliiim, by v.lioin the nume was origin-
ally given, is that in which the quantity of
the proposition is contingently changed
either from greater to less, or from less to
greater, na'.va. xcriktte, the quality of the terms
and propositions remaining always the same.
So Kidiger, De Sensu Veri et Falti, p. SOS.
The second is that of logicians in general,
where the quantity of the proposition is di-
minished, the quality of tlic propositions and
terms remaining the same, salva xfritatf.]
1 Melanchthon I Erotetnaln. L. ii. i> Con-
veninnf, p. 516), followed by his pupil and
commentator Strigelius (/» EroUtiuUa, p^
APPENDIX.
527
But, 3°, If the preceding theory be true, — if it be true that subject and
predicate are, as quantified, always simply convertible, the proposition being
in fact only an enouncement of their equation, it follows (and this also is an
adequate test) that we may at will identify the two' terms by making them both
the subject or both the predicate of the same proposition. And this we can
do. For we can not only say — as A in B, so conversely B « A, or as All men
are some animals, so, conversely, Some animals are all men; but equally say —
A and B are convertible, or, Convertible are B and A ; AU men and some ani-
mals are convertible (that is, some convertible things), or. Convertible (that is,-
some convertible things) are some animals and all men. By convertible, I mean
the same, the identical, the congruent, etc.^.
576, 581), and by Kcckermann (Syst. Log.
Minus, L. ii. c. 3, Op. p. 222), and others,
thinks that "there is a greater force of the
particle none {niiUiis, not any), than of the
I)article all (oninis). For, in a universal neg-
ative, the force of the negation is so spread
over the whole proposition, that in its con-
version the same sign is retained (as — No
star is ronsumeci ; therefore, no flame which, is
consumed is a ftar): whereas such conversion
does not take place in a universal affirma-
tive." This Strigelius compares to the dif-
fusion of a ferment or acute poison; adding
that the affirmative particle is limited to the
subject, whilst the negative extends to both
subject and predicate, in other words, to the
whole proposition.
This doctrine is altogether erroneous. It is
an erroneous theory devised to explain an
erroneous practice. In thg first place, we
have here a commutation of negation with
quantification; and, at the same time, con-
verj;ion. direct conversion at least, will not
be said to change the quality cither of a neg-
ative or affirmative proposition. In the sec-
ond place, it cannot be pretended that nega-
tion has an exclusive or even greater affinity
to universal than to particular quantification.
VTe can equally well say not some, not all, not
antj ; and the reason why one of these forms
is preferred lies certainly not in any attrac-
tion or afiSnity to the negative particle]
1 [With the doctrine of Conversion taught
In the text, compare the following authori-
ties: Laurentius Valla, Dialeciica, L. ii. c.
24, f 3". Titius, Ars Coeilif^\di (v, Ridigerj fla
Sensu Veri tt Falsi, L ii. c. i. p 232). Rcusch,
Systema Logicum, § 380, p. 413 ft stg., ed. 1741.
Uollmann, Logica, § 89, p. 172. riouc<iuet.
Fries, Logik, § S3, p. 146. R. Reinhold, Logik,
§ 117, p. 286. Arcients referred to by Ammo-
nius. In De Interp , c. vii. § 4, f. . . . . Faulus
Vallius, Lo!;ica, t. ii.. In An. Prior., L. i. q. ii.
c. iv.] [Valla I. c. says: " Xon amplius ac
latius accipitur prjedicatum quam subjectum.
Idcoque cum illo converti potest, ut omnis
homo est animal: non utique totum genus ani-
mal, sed aliqua pars hujus generis. . . . ergo,
Aliqua pars animrdis est in ontni honiine. Item,
Quidam homo e^t animal, scilicet est queEiiatn
pars anitnalis, ergo, Qumdam pars aninialis est
quidam homo, etc." Gottlieb Gerhard Titius,
Ars Cogitandi, c. vii. § 3 ^ f seq., p. 125. LipsiJE,
1723 (first ed. 1701). " Nihil autem aliud agit
Conversio, quam nt simpliciter pradicatum
et subjectum transponat, hinc nee qualitatem
nee quantitatem lis largitur, aut eas niutat,
sed prout reperit, ita convertit. Ex quo neces-
sario sequitur conversionem esse uniformem
ac omnes propositiones eodem plane moJe
converti. Per exempla, (1), NuUus homo est
lapis, ergo, Nullus lapis est homo. (2), Quidam
homo non est medinis (omnis), ergo, JMedicus
non est homo quidam, seu Nullus medicus est
homo quidain (3), Hie Petrus 7ion
est doctus (omnis), ergo, Omnis doctiis non est
hie Petrus. .... (4), Omnis homo est ani-
mal (quoddam), ergo, Quoddam animal est
hon.o. (5), Quidavi homo currit [parti culariter),
ergo, Quidam currens est homo. (6), Hie Paulus
est doctus (quidam), ergo, Quidam doctus est hie
Paulus. In omnibus his exemplis subjectum
cum sua quantitate in locum prasdicati, et
hoc, eodem modo, in illius sedem transponi-
tur, ut nulla penitus ratio solida appareat,
quare conversionem in diversas species divel-
lere debeamus. Vnlgo tamen aliter sentiunt
quando triplicem conversionem, nempe sim-
plicem, per accidens, acper eontrapositionem, ad-
struunt Enimvero conversio per
accidens et per eontrapositionem gratis asseritur,
nam conversio propositionis affirmantis uni-
versalis perinde simplex est ac ea qua univer-
salis negans convertitur, licet post eam sub-
jectum sit particulare; conversionis enim hie
nulla culpa est, quae quantitatem, quse non
adcst, largiri nee potest nee debet
Error vulgaris doctrinas, nisi fallor, inde est,
quod existimaverint ad conversionem simpli-
cem requiri, ut prctdicatum assumat signu7n et
quantitatem subjecti Conversionem
per eontrapositionem quod attinet, facile ostendi
5-28
APPENDIX
The general errors in regard to Conversion, — the errors from which all the
rest proceed, arc —
1^, The omission to quantify the predicate throughout.
2°, The conceit that the quantities did not belong to the terms.
3°, The conceit that the quantities were not to be transposed with their
relative terms.
4°, The one-sided view that the proposition was not equally composed of the
two terms, but was more dependent on the subject than on the predicate.
5°, The consequent error that the quantity of the subject term determines
the quantity of the proposition absolutely.
G°, The consequent error that there was any increase or diminution of the
total quantity of the proposition.
7°, That thorough-going conversion could not take place by one, and that
the simple, form.
8°, That all called in at least the form of Accidental Conversion ; all admit-
ting at the same time that certain moods remain inconvertible.
9°, Tliat the majority of logicians resorted to Contraposition (which is not
a conversion at all) ; some of them, however, as Burgersdyk, admitting that
certain moods still remained obstinately inconvertible.
10°, That they thus introduced a form which was at best indirect, vague,
and useless, in fact not a conversion at all.
11°, That even admitting that all the moods were convertible by one or
other of the three forms, the same mood was convertible by more than one.
1 2°, That all this mass of error and confusion was from their overlookiiig
the necessity of one simple and direct mode of conversion ; missing the one
straight road.
We have shown that a judgment (or proposition) is* only a comparison re-
sulting in a congruence, an equation, or non-equation of two notions in the
quantity of Extension ; and that these compared notions may stand to each
potest (1) exempla heic Jactari solita, posse
converti simpHciter; (2) conversionem per
contrapositiciiem, revera non esse conversio-
nem; interim (3) putativam istam conver-
sionem non in universali affirmante, et partic-
ular! ne^ante solum, sed in omnibus potius
propositionibus locum habere, . . . e. g.,
Qtio'liJam animal non est guadrupes, ergo. Nul-
lum quaihupes est animal guodUam.'^ See the
criticism of the doctrine of Titius by Ridiger,
quoted below, p. 555. Ploucquet, Methodus
CaUulandi in Logicis, p. 49 (1763). " Intellec-
tic identitatis subject! et prsedicati est affirma-
lio Omnis circulus est linea curva.
Qua; propositio logice expressa haec est : —
Omnis circulus est quirdam linea rurva. Quo
pacto id, quod intelligitur in pra?dicato iden-
tificatur cum eo quod intelligitur in subjecto.
Sive norim, sive non norim praiter circulum
dar! quoque alias ciirvnriim species, verum
tamen est quondam lineam curvam sensu
comprehensivo sumtam, esse omnem circulnm,
seu omnem circulum esse quandam lineam
curvam." Vallius, /. c. '• Xegativas vero con-
vertuntur et in particulares et in univer-
sales negatives; ut si dicamus, Socrates non
est lapis, convertens illius erit, Aliquis lapis
non est Socrates, et NuUus lapis est Socrates, et
idem dicendum erit de omni alia simili prop-
ositione.'' — Ed.]
[That Universal Affirmative Propositions
may be converted simply, if their predi-
cates are reciprocating, see Corvinus, Instit,
Phil. Rat., § 514 Jens, 1742. Baumgartcn,
Logica, § 280, 1765. Scotus, In An. Pr., L.
i. qu. 14. Ulrich, Instit. Log. et. Met., | 1.2,
177 (1785). Kreil, Logik, §§ 46, 62 (1789). Is-
endoom, Logica Perlpatetica, L. iii. c. 8, pp.
430, 431. Wallis, Logica, L. ii. c 7. Zabar-
ella, In An. Prior. TdbuUr., p. 148. Lambert,
X)3 Vnivirsaliori Calculi Idea, ( 24 et seq.]
APPENDIX.
529
other as the one subject and the other predicate, as both the subject, or as
both the predicate of the judgment. If this be true, the transposition of the
terms of a proposition sinks in a very easy and a very simple process ; whilst
the whole doctrine of logical Conversion is superseded as operose and imper-
fect, as useless and erroneous. The systems, new and old, must stand or fall
with their doctrines of the Conversion of propositions.
Thus, according to the doctrine of the logicians, conversion applies only to
the naked terms themselves : — the subject and predicate of the prejacent
interchange places, but the quantity by whi(;h each was therein affected is
excluded from the movement; remaining to aifect its correlative in the subja-
cent proposition. This is altogether erroneous. In conversion we transpose
the compared notions, — the correlated terms. If we do not, eversion, not
conversion, is the result.
If (as the Logicians suppose) in the convertens the subject and predicate
took each other's quantity, the proposition would be not the same relation of
the same notions. It makes no difference that the converse only takes place-
when the subject chances to have an equal amount or a less than the predicate.
There must be at any rate a reasoning (concealed indeed) to warrant it: in
the former case — that the predicate is entitled to take all the quantity of the
subject, being itself of equivalent amount ; in the second (a reasoning of sub-
alternation), that it is entitled to take the quantity of the subject, being less
than its own. All this is false. Subject and predicate have a right to their
own, and only to their ov/n, which they carry with them, when they become
each other.
IV. — Application of Doctrine of Quantified Pkedigate to Propc>sition8.
(a) SEW PROI'OSiriONAL FOKMS- NOTATION.
Instead of four species of Proposition determined by the Quantity and
Quality taken together, the Quantity of the Subject being alone considered,
there are double that number, the Quantity of the Predicate being also taken
into account.
Irma
tive.
(1)
[AfA]
C
(")
[Afl]
C
(3)
[If A]
A
(iv)
[If I]
C
r All Triangle is all Trilateral [fig. 1].
A All Triangle is some Figure (A) [fig. 2],
C Some Figure is all Triangle [fig. 2].
B Some Triangle is some Equilateral (I)
[fig. 4].
67
530
APPENDIX.
Negative.
(v) [EnE] C:i
(A) (A)
(6) [E n O] C : .
(A) (I)
(vii) [OnE] B,,
(I) (A)
(8) [OnO] C,.
(I) (I)
: D Any Triangle is not any Square (E) [fig. 3}.
• , B Any Triangle is not some Equilateral
[fig. 4].
• : C Some Equilateral is not any Triangle (O)
[fig; 4].
, B Some Triangle is not some Equilateral
[fig. 4].^
(6) QUANTITY OF PROPOSITIONS - DEFINTWDE AND INDEFINTTUDS.
Nothing can exceed the ambiguity, vacillation, and uncertainty of logicians
foncerning the Quantity of Propositions.
I. As regards what are called indefinite (^iSi6pi(TToi) more properly indesignate
or preindesignate propositions. The absence of overt quantification applies only
to the subject ; for the predicate was supposed always in aflirmatives to be
particular, in negatives to be universal. Referring, therefore, only to the
indesignation of the subject : — indefinites were by some logicians (as the
Greek commentators on Aristotle (?), Apuleius apud Waitz, In Org. i. p. 338,
but see Wegelin, In An'eponymi Phil. Sgn., p. 588) made tantamount to par-
ticulars; by others (as Valla, Dialectica, L. ii. c. 24, f. 37), made tantamount
1 [In this table the Roman numerals dis-
tinguish such prepositional forms as arc rec-
ognized in the AristoteliC or common doc-
trine, whereas the Arabic ciphers mark those
(halt* of the whole) which I think ought like-
wise to be recognized. In the literal symbols,
I simplify and disintricate the scholastic nota-
tion ; taking A and I for universal and par-
ticular, but, extending them to either quality,
marking affirmation by f, negation by u, the
two first consonants of the verbs affirmo and
K,ego. — verbs from which I have no doubt
that Petrus Uispanus drew, respectively, the
two first vowels, to denote his lour complica-
tions of quantity and quality.] — Discussions,
p. 686.
[In the notation employed above, the
comma , denotes some ; the colon : all ; the
line m denotes the affirmative copula,
and negation is expressed by drawing a line
through the affirmative copula ■ [ ; the
thick end of the line denotes the subject, the
thin end the predicate, of Extension. In In-
tension the thin end denotes the subject, the
thick end the predicate. Thus : — C : » ,
A is read. AU C is some A. C : »^ — : D is
read, No C is any D. The Table given in the
text is from a copy of an early scheme of the
author's new Propositional Forms. For some
time after his discovery of the doctrine of a
quantified predicate. Sir W. Hamilton seems
to have used the vowels E and O in the for-
mulae of Negative Propositions; and the full
period {.) as the symbol of some (indefinite
quantity). In the college session of 1845-46,
he had adopted the comma (,) as the symbol
of indefinite quantity. As the period ap-
pears in the original copy of this Table" as the
symbol of some, its date cannot be later
than 1845. The comma (,) has been substi-
tuted by the Editors, to adapt the Table to
the Author's latest form of notation. The
translation of its symbols into concrete prop-
ositions, affords decisive evidence of the
meaning which the Author attached to them
on the new doctrine. That this, moreover,
was the uniform import of Sir W. Hamil-
ton's propositional notation, from the earli-
est development of the theory of a quantified
predicate, is placed beyond doubt by numer-
ous passages in papers (not printed), and by
marginal notes on books, written at various
\)eriods between 1839-40, and the date of his
illness, July 1844, when he was compelled to
employ an amanuensis. The letters in round
brackets (A) and (I) are the vowels finally
adopted by the Author, in place of E and O
See p. 534. — Ed.]
APPENDIX. 631
to universals. They ought to have been considered as merely elliptical, and to
be definitely referable either to particulars or universals.^
II. A remarkable uncertainty prevails in regard to the meaning of particu-
larity and its signs, — some, etc. Here some may mean some only, — some not
all. Here some, though always in a certain degree indefinite, is definite so far
as it excludes omnitude, — is used in opposition to all. This I would call its
Semi-definite meaning. On the other hand, some may mean some at least, —
some, perhaps all. In this signification some is thoroughly indefinite, as it does
not exclude omnitude or totality. This meaning I would call the Indefinite.
Now of these two meanings there is no doubt that Aristotle used particularity
only in the second, or thoroughly Indefinite, meaning. For, 1°, He does not
recognize the incompossibility of the superordinate and subordinate. 2°, He
makes all and oh vu.%, or particular negative, to be contradictories ; that is, one
necessarily true, the other necessarily false. But this is not the case in the
Semi-definite meaning. The same holds good in the Universal Negative and
Particular Affirmative.
The particularity — the some — is held to be a definite some when the other
term is Definite, as in ii. and 3, in 6 and vii. On the other hand, when both
terms are Indefinite and Particular, as in iv. and 8, the some of each is left
wholly indefinite.
The quantification of definitude or non-particularity (:) may designate am-
biguously or indifferently one or other of three concepts. 1°, It may designate
explicit omnitude or totality ; which, when expressed articulately, may be
denoted by (: :). Thus — All triangles are all trilalerals. 2°, It may designate
a class considered as undivided, though not positively thought as taken in its
whole extent ; and this may be ai'ticulately denoted by (: .). Thus — The iri-
ancfle is the trilateral; — The dor/ is the latrant. (Here note the use of the def-
inite'article in English, Greek, French, German,^ etc.) 3°, It may designate not
1 [That Indefinite propositions are to be re- Ramus, Scliol. Dial., L. vii. c. 2, . p. 457.
lerred to universals, see Purcliot, Instit. Pliil. Downam, In Rami Dialect., L. ii. c. 4, p. 850.
Logica, I. ^ ii. c. 2, pp. 124, 125, 126. Itottt'n- Facciolati, Rud. Log. p. ii. c. iii., p., 67. De-
beccius, Logica Contracta, c. vi. p. 92 (1660). lariviere, Nouvelle Logique Classique, L. ii. s.
Baumeister, Inst. Phil. Rat., § 213. J. C. Seal- ii. c. 3, s. 580, p. 334.
iger, Exerciiatiows, Ex. 212, 5 2. Drobisch, That Indeflnitude has sometimes a logical
Logik, ^ 39. Neomagus, Ad Trapezunlium , f. import, when we do not know whether aK.
10. To be referred to particular; see Lovan- or some, of the one be to be affirmed or de-
ienses, Com. in Arist. Dial. p. 161. Molinaeus, nied of the other: E. Reinhold, Logik, § 88.
Elemenla Logica, L. I. c. 2. Alex. Aphrod., Anm. 2, pp. 193, 194. Ploucquet, Metkodiis
In An. Prior., c. ii. p. 19. Denzinger, Logica, Calculandi, pp. 48, 53, ed. 1773. Lambert,
S 71. Either universal or particular, Keeker- Neues Organon, I., § 235, p. 143.]
mann, Opera, p. 220. Aristotle doubts; see 2 [On effect of the definite article and its
An. Prior., L. \. c. 27, f 7, and De Interp. c. 7. absence in different languages, in reducing
That Indefinitude is no separate species of the definite to the indefinite, see Delarivi6re,
quantity, see Scheibler, Opera Logica, p. iii. c. Logique, ^ 580, 581.
6, p. 443. Graecus Anonymus, De Syllogismo, On the Greek article, see Ammonius, In De
L. i. c. 4, f. 42. Leibnitz, Opera, t. iv. p. iii. Interp. c. vii. f. 67 b.
p. 123. Fries, SijMetn der Logik, } 30, p. 137. On use of the Arabic article in quantifica*
532
APPENDIX.
what IS merely undivided, thoi/gh divisible, — a class, but what Is indivisible, —
an individual ; and this may be marked by the small letter or by (: •) — Thus
— Socrates is the husband of Xanthippe ; — This horse is Bucephalus.
In like manner particularity or indefinitude (,), when we wish to mark it as
thoroughly indefinite, may be designated by (' ,), whereas when we would
mark it as definitely indefioite, as excluding all or not any, may be marked
by(")-
The indefinites (a<$pHrTo) of Aristotle correspond sometimes to the particular,
sometimes to one or other, of the two kinds of univcrsals.^
The designation of indefinitude ov particularitij, some (, or ,) may mean one
or other of two very different things.
1**, It may mean some and some only, being neither all nor none, and in tlils
sense it will be both affirmative and negative (,r).
2°, It may mean, negatively, not all, perhaps none, some at most; affirmatively,
ROt none, perhaps all, — some at least (, ,).
Aristotle and the logicians contemplate only the second moaning. The
reason of this perhaps is, that this distinction only emerges In the conslderatlosi
of Opposition and Immediate Inference, which were less elaborated In the
former theories of Logic ; and does not obtrude itself in the consideration of
Mediate Inference, which is there principally developed." On the doctrine of
the logicians, there Is no ojiposltlon of subalternatlon ; and by Aristotle no
opposition of subalternatlon is mentioned. By other logicians it was errone-
ously Introduced. The opposition of Subcontraries Is, likewise, improper,
being precarious and not between the same things. Aristotle, though he
enumerates this opposition, was quite aware of its impropriety, and declares it
to be merely verbal, not real.*
tion, see Averrofes, De Intcrp , p. 39, edition
1552:
"4i in the Arabic tongue, and Ha in tbe
Hebrew, and iu lilce mauuer the articles in
other languages, sometimes have tlu; power
of universal predesiguations, sometimes of
particular. If the former, then they have
the force of contraries; if the latter, tlien the
force of sub-contraries. For it is true to say,
al, that is, ipse homo is white, and a/, that is,
ipse homo is not white ; tliat is, wljcn the arti-
cle ai or ha, that is, ipse, denotes the designa-
tion of particularity. They may, however,
be at once false, when the article al or ha has
the force of the universal predesignation."
(See also p. 52 of the same book.)
In Knglish the definite article always de-
fines, — renders definite, — but sometimes in-
dividuahzes, and sometimes generalizes. If
wo would use man generally, we must not
prefix tiie article, as iu Greek, German,
French, etc ; so wealth, government, etc. But
in definition of horse, etc., the reverse, as the
dog {l« chien, 6 Kvaiv, etc.). A in English is
often equivalent to anji^l
1 [Logicians who have marked the Quanti-
ties by Definite, Indefinite, etc.
Aristotle, An. Pr., c. iv. § 21, and there Al-
exander, Pacius. Theophrasfus (Facdolati,
Kud. Log., p. i. c. 4, p. 39). Ammonius, In
De Inter., f. 72 b. (Brandis, Scholia, p. 113)
Stoics aud Non-peripatetic Logicians in gen-
eral, see Sext. Empiricus, 4</f. Ln^., § 98<Xie? ,
p. 476, ed. Fabricii; Diog. Laert. Lib. vii. .teq.
71, «bi Meuagius. Downam, In Rami Dialeo-
ticam, L ii. c. 4, p. 363, notices that a partior
ular proposition " was called by the Stoic*
indefinite [aiptaTov) ; by some latins, aud
sometimes by Ramus himself, infinite; be-
cause it does not designate some certain
species, but leaves it uncertain and intiefi-
nite." Hurtado de Mcndoza, Di.^p. Lo^. »«
Met., t. i. d. iv. i 2, p. 114. Lovaniense.*, la
Ari.1t. Dial., p. 161. HoUmann, Logita, p. 173.
Boethius, Opera, p. 345. Reusch, Syst. Log.,
p 424. Esser, Log-i/fc, 5 58. Weiss, Zx)g^it, H 149,
150. So Kiesewetler, I^g-k, §§ 102, 103.]
2 On both forms of Opposition, see Scheib-
ier,lOpera Logica, ^ iii., rfe Propositi/inibus,^^
xt p. 487, and above, p. 134. -^ £»■]
APPENDIX. 633
By the introduction of the first meaning of some, we obtain a veritable
opposition in Subalternation ; and an inference in Subcontrariety, which I
would call Integration.
(c) OPPOSITION OF PnOPOSlTJONS.
Propositions may be considered under two views ; according as their par-
ticularity, or indefinitude, is supposed to be thoroughly indefinite, unexclusivc
even of the definite : some, meaning some at least, some, perhaps all, some, per-
haps not any ; or definite indefinitude, and so exclusive of the definite ; smne,
meaning some at most, — some only, — some not all, etc. The latter thus excludes
omnitude or totality, positive or negative ; the former does not. The former is
the view promulgated as alone contemplated by Aristotle; and has been
inherited from him by the Logicians, without thought of increase or of change.
The latter is the view which I would introduce ; and though it may not super-
sede, ought, I think, to have been placed alongside of the other.
Causes of the introduction of the Aristotelic system alone :
1°, To allow a harmony of Logic with common language ; for language
eliding all that is not of immediate interest, and the determination of the
subject-notion being generally that alone intended, the predicate is only con-
sidered in so far as it is thought to cover the subject ; that is, to be at least
coextensive with it But if we should convert the terms, the inadequacy would
be brought to light
2°, A great number of notions are used principally, if not exclusively, as
attributes, and not as subjects. Men are, consecjuently, very commonly igno-
rant of the proportion of the extension between the subjects and predicates,
which they are in the habit of combining into propositions.
3°, In i"cgard to negatives, men naturally preferred to attribute positively a
part of one notion to another than to deny a part Hence the unfrequency of
negative? with a particular predicate.
On the doctiine of Semi-definite Particularity, I would thus evolve the
Opposition or Incompossibility of propositions, neglecting or throwing aside
(with Aristotle) those of Subalternation and Sub-contrariety, but introducing
that of InconsiMency,
Incompossibility is either of propositions of the same, or of different, quality.
Incompossible propositions differing in quality are either Contradictories without
a mean, — no third, — that is, if one bo true the other must be false, and if one
be false the other must be true ; or Contraries with a mean, — a third, — that
is, both may be false, but both cannot be true. Incompossible propositions of
the same quality are Inconsistents, and, like Contraries, they have a mean ; that
is, both may be false, but both cannot be true.
Contradictories are again either simple or complex. The simple are either,
1°, Of Universals,*as undivided wholes; or, 2", Of Individuals, as indivisible
parts.*
1 General tenlis, used as individual teHnd, So that there are three kinds of contradic-
wbtiii opposed to each other, may be contra- tories.
dictories, as Man is mortal, Man is not mortal.
534
APPENDIX.
The complex are of universals divided, as 4 — 5.
Contraries, a«;ain, which are only of divided universals, are, 1°, Bilateral, aa
1—5 ; or, 2°, Unilateral, as 1 — 6, 1—7, 2—5, 3 — 5; or, 3°, Cross, as 2—7, S— 6.
Inconsistents are either, 1°, Affirmatives ; or, 2°, Negatives. Affirmatives, as
1 — 2, 1 — 3, 2 — 3. Negatives, as 5 — 6, 5 — 7, The propositions 6 — 7 are some-
times Inconsistents, sometimes Consistents.
All the other propositional forms, whether of the same or of different quali-
ties, are Compossible, or Unopposed.
The differences in compossibility of the two schemes of Indefinite and Defi-
nite particularity lies, 1°, In the whole Inconsistents ; 2°, In two Contraries for
Contradictories. 1°, According to the former, all affirmative and all negativo
propositions are consistent, whereas in the latter these are inconsistent, 1 — 2,
1 — 3, 2 — 3; among the affirmatives, and among the negatives, 5 — 6, 5 — 7.
(As said before, 6 — 7 is in both schemes sometimes compossible, and sometimes
incompossible.) 2°, Two incompossibles, to wit, 2 — 7, 3 — 6, which, on the
Aristotelic doctrines, are Contradictories, are in mine Contraries.
The propositional form 4 is consistent with all the affirmatives ; 8 Is not only
consistent with all the negatives, but is compossible with every other form in
universals. It is useful only to divide a class, and is opposed only by the
negation of divisibility.
By adopting exclusively the Indefinite particularity, logicians threw away some
important Immediate inferences; those, to wit, 1°, From the affirmation of one
tome to the negation of another, and vice versa : and, 2°, From the affirmation
of one inconsistent to the negation of another. 1°, Thus, on our system, but
not on theirs, affirming all wan lo be some animal, we have a right to Infer that
no man is some (other) animal ; affirming that some animal is all man, we have
a right to infer that some (other) animal is not any man ; affirming some men are
tome blacks (Nerp-oes), we are entitled to say that (same) some men are not some
(other) blacks (Hindoos), and also that (other) some men are not the (same) some
blacks. And so backwards from negation to affirmation. This inference I
would call that of [Integration].
2°, Affirming a// men are some animab, we are entitled to infer the denial of
the propositions, all men are all animalSy some men are all animals. And so iu
the negative inconsistents.
Affirmatives.
1.) Toto-total = Afa= All — Is all — .
ii.) Toto-partial = Afi = All — Is some — . (A)
S.) Parti-total = Ifa = Some — Is all — .
iv.) Parti-partial = Ifi ^ Some — is some — . (I)
V.) Toto-total
6.) Toto-partial
vil.) Parti-total
8.) Parti-partial
Negatives.
Ana = Any — is not any — . (E)
An I = Any — Is not some — .
Ina ^ Some — Is not any — . (O)
In I = Some — is not some — .
APPENDIX,
536
TABLE OF THE Mutual Relations of the Eight Propositional Forms oh
Either System of Pakticularity. (For Generals only.)
>
<: t2!
>
«
< < < < 03Wwco3:3:s:3:i-'h-(— ►-'Elj
1 1 1 1 1 1 1 1 M M 1 1 1 1 ;^
■z:<^Zi< < ■<! "
1 1 1 1 1 l=g
00 00 <_ 00 ;<_ 0 r'
ml
fl
— -1
p.
3 = 3
- -
!i = S
! 1 1 1 1 1 1 1 i 1 1 1 1 1 1 1
5*>> >»>>->
!=;>;> !>>!>
o!!«5
P 3 3 3 3 3
1 1 1 1 1 1
?3>3-.
1 1 1
1 1 1
t
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1
1 1 1
1 1 1
s
5* •
E.S33C.g33=.S33--p33
3* 3' 3* 3^ 3*^
— — P> — P s.
33^
a
5d jcr::' w o ceo
0
„
<D reO n> O OOO
0
0
•o 'H='S g. SxS
c
"1
CR Jjp Jjj p ppp
p 3;^ 3 ^ rr'r'
C 0*3 cr 3 3 = 3*
1
3 S>
1-
r- r- 3 r- 3 33 .—
Q
^ 1
3-2 0
p. 2 ' 2 "
C^ 3
re - 2
r^ r* r*
*
"l-i«
9 00 0 0 990
p 33 3 3 5 = 2.
0 5-5^
1 §s
C B 3
3
0
0
^-3
0 0
3 3
2 H-
£0 f*
p 0p p p ppp
5= "^
?
alEs-
SS.-^
bi.
un.
un.
un.
bi. cr.
un.
. bi. cr.
bi. di.
--* C 3
0 ??
71
3
3
0
7!
3 3
3 3
fl
a
0
3
__
►-.-5"_.
< 1 <
\k\ ^.^ -. -. ^
00 3:p M-J^ T T T
=:o -J <! ««
II III
Tf
TTT
Is
00-^ 0> 00 ^_ 00 0> 00
II III
00 00 00 <. Oi
►L J.
^F
g"
1 7' 1 ""■
""■
g
^ J..<
§•
■§
•^ 3
•^
fdW WWW
WW
www
g- §■
^o*
0 fD 0 ffi <D
fll tB
a a a
3 31
* " V
ce M en CK en
Zfi rji
»?l
0 *
c» rt- r* rt r»
T''
7. ^ 7! r^ r-
? ?
r" r* r"
oSg-«
03° «^
C 3 c-C 3
3 S
0*3 3
3 3 r-3 3
3 3
23 3
(t 0 ta
g
=<WW W=< W 5* w
3<B<t <ti3. 0 5 <»
WW w
WW
w
M
3
0
0 <p 0
0 a
s
r- »
3
ffS"?'??? ?"???■
rt- S- "'
«■ ?♦
& §■
r g^g* ^ 8= ? 8=
? ? ?
r* r*
>1
^?l
5
£".33 bS 3 S 3
c 3 cr
33 r-
3 3
3 3
0;
= ." 3
r^^rt c.r3 «- 3 f^
i S-
CSC C C*
5 1
3 3 3 3 r-
Abbreviations: — bi. = &i7a<era/ ; cr.= cross; Contrar. = Contraries; di. = direct;
Incons. = Inconsistents ; Int. or Integr. = Integration; Repugn. = Mepugnants, Con-
tradictories; Res. or Restr. = Restriction, Subalternation ; un. = unilatei'al. Blanks:
in I. = Compossibles ; in II. = No inference. — ( Unilateral, bilateral, cross, direct, refer
to the Extreme.?.)
The preceding Table may not be quite accurate in details.
536 APPENDIX.
V. — Syllogisms.
OBSEBVATIOKS ON THB MUTUAL RELATIONS OF SYLLOGISTIC TEEMS .IN QUAN-
TITY AND QCAUTT.
General Canon. — What worst relation of subject and predicate subsists between
either of two terms and a common third term, with which one, at least, is positively
related ; that relation subsists between the two terms themselves.
There are only three possible relations of Terms (notions, representations,
presentations).
1°, The relation of Toto-total Colnclusion (cdidentity, absolute convertibility
or reciprocation) (AfA).
2", The relation of Toto-total Coexclusion (non-identity, absolute inconverti-
bility or non-reciprocation) (AnA).
3°, The relation of Incomplete Colnclusion, which involves the counter-reljt-
tion of Incomplete Coexclusion (partial identity and non-identity, relative con-
vertibility and non-convertibility, reciprocation, and non-reciprocation). This
is of various orders and degrees.
a) Where the whole of one term and the part of another are coinclusive or
coideiitical (Afl). This I call the relation of ioto-partial coinclunion, as, All
men are some animals. This necessarily involves the counter-relation of toto-
partial coexclusion (AnI), as, Any man is not some animal. But the converse
of this afllrmative and negative affords the relations of
b) Parti-lotal Colnclusion (IfA) and Coexclusion (InA), as, Some animal is
all man, Some animal is not any man.
c) There is still a third double relation under this head, when two tenns
partially include and partially exclude each other (If I Inl), as, Some women are
some authors, and Some women are not some authors. This relation I call that
of Parti-partial Colnclusion and Parti-partial Coexclusion.
Of these three general relations, the first is [technically stj'led] the best ; the
second is the worst ; and the third is intermediate.
Former logicians knew only of two worse relations, — a particular, worse
than a universal, affirmative, and a negative worse than an affirmative. As to
a better and worse in negatives, they knew nothing; for as two negative
premises were inadmissible, they had no occasion to determine which of two
negatives was the worse or better. But in quantifying the predicate, in con-
necting positive and negative moods, and in generalizing a one supreme canon
of syllogism, we are compelled to look further, to consider the inverse proced-
ures of affirmation and negation, and to show (e. (/., in v. a. and vi. b., ix. a.
and X. b.) how the latter, by reversing the former, and turning the best quan-
tity of affirmation into the worst of negation, annuls all restriction, and thus
apparently varies the quantity of the conclusion. It thus becomes necessary to
show the whole order of best and woi-st quantification throughout the two
APPENDIX.
63T
qualities, and how affirmation commences with the whole in Inclusion and
Negation, with the parts in Exclusion.^
Toto-total,
Toto-partial,
Parti-total,
Parti-partial.
Parti-partial,
Parti-total,
Toto-partial,
Toto-total.
Identity or Clomclosion.
Non-identity or coexclosion.
As the negation always reduces the best to the worst relation, in the inter-
mediate relations determining only a commutation from equal to equal, whilst
in both the symbols of quantity, in their inverse signification, remain externally
the same ; it is evident that the quantification of the conclusion will rarely be
apparently different in the negative from what it is in the corresponding
positive mood. There are, indeed, only four differences to be found in the
negative from the positive conclusions, and these all proceed on the same
principle — viz., in v. a. and vi. b., in ix. a. and x. b. Here- the particular
quantification of the positive conclusions disappears in the negative moods.
But this is in obedience to the general canon of syllogism, — " That the worst
relation subsisting between either extreme and the middle, should subsist
between the extremes themselves." For what was the best relation in the
former, becomes the worst in the latter ; and as affirmation comes in from the
greatest whole, while negation goes out from the least part, so, in point of fact,
the some of the one may become the not any of the other. There is here,
therefore, manifestly no exception. On the contrary, this affords a striking
example of the universal applicability of the canon under every change of
circumstances. The canon would, in fact, have been invalidated, had the
apparent anomaly not emerged.
I. Terms each totally co'inclusive of
a third, are totally coinclusive of each
other.
n. Terms each parti-totally coinclu-
sive of a third, are partially coinclusive
of each other.
a) A term totally coexclusive, and
a term totally coinclusive, of a third,
are totally coexclusive of each other.
b) A term totally coinclusive, and
a term totally coexclusive, of a third,
are totally coexclusive of each other.
a) A term parti-totally coexclusive,
and a term parti-totally coinclusive,
of a third, are partially coexclusive of
each other.
b) A term parti-totally coinclusive^
and a term parti-totally coexclusive,
of a third, are partially coexclusive of
each other.
1 See Magentious (in Brandis, Scholia, p. 113, and there the FIatonics>
G8
638
APPENDIX.
III. A term totally, and a term par-
ti-totally, coinclusive of a third, are
toto-partially coinclusive of each other.
rV. A term partl-totally, and a term
totally, coinclusive of a third, are parti-
totally coinclusive of each other.
V. A term totally, and a term toto-
partially, coinclusive of a third, are
parti-totally coinclusive of each other.
VI. A term toto-partially, and a
term totally, coinclusive of a third, are
toto-partially coinclusive of each other.
Vli. A term parti-totally, and a
term partially, coinclusive of a third,
are partially coinclusive of each other.
Vni. A term partially, and a term
parti-totally, coinclusive of a third, are
partially coinclusive of each other.
a) A term totally coexclusive, and
a term parti-totally coinclusive, of a
third, ^i-e toto-partially coexclusive of
each other.
b) A term totally coinclusive, and
a term parti-totally coexclusive, of a.
third, are toto-partially coexclusive of
each other.
a) A term parti-totally coexclusive,
and a term totally coinclusive, of a
third, are parti-totally coexclusive of
each other.
b) A term parti-totally coinclusive,
and a term totally coexclusive, of a
third, are parti-totally coexclusive of
each other.
a) A term totally coexclusive, and
a term toto-partially coinclusive, of a
third, are totally coexclusive of each
other.
b) A term totally coinclusive, and
a term toto-partially coexclusive, of a
third, are parti-totally coexclusive of
each other.
a) A term toto-partially coexclu-
sive, and a term totally coinclusive, of
a third, are toto-partially coexclusive
of each other.
b) A term toto-partially coinclusive,
and a term totally coexclusive, of a
third, are totally coexclusive of each
other.
a) A term parti-totally coexclusive,
and a term partially coinclusive, of a
third, are partially coexclusive of each
other.
b) A term parti-totally coinclusive,
and a term partially coexclusive, of a
third, are partially coexclusive of each
other.
a) A term partially coexclusive, and
a term parti-totally coinclusive, of a
third, are partially coexclusive of each
other.
b) A term partially coinclusive, and
a tenn parti-totally coexclusive, of a
third, are partially coexclusive of each
other.
APPENDIX.
639
IX. A tema totally, and a term par-
tially, coinclusive of a third, are par-
tially coinclusive of each other.
X. A term partially, and a term
totally, coinclusive of a third, are par-
tially coinclusive of each other.
XL A term parti-totally, and a term
toto-partially, coinclusive of a third,
are parti-totally coinclusive of each
other.
XH. A term toto-partially, and a
term parti-totally, coinclusive of a third,
are toto-partially coinclusive of each
other.
a) A term totally coexclusive, and
a term partially coinclusive, of a third,
are totally coexclusive of each other.
b) A term totally coinclusive, and a
term partially coexclusive, of a third,
are partially coexclusive of each other.
a) A term partially coexclusive, and
a term totally coinclusive of a third,
are partially coexclusive of each other.
b) A term partially coinclusive, and
a term totally coexclusive, of a third,
are toto-partially coexclusive of each
other.
a) A term parti-totally coexclusive,
and a term toto-partially coinclusive, of
a third, are parti-totally coexclusive of
each other.
b) A term parti-totally coinclusive,
and a term toto-partially coexclusive,
of a third, are parti-totally coexclusive
of each other.
a) A term toto-partially coexclusive,
and a term toto-partially coinclusive, of
a third, are toto-partially coexclusive
of each other.
b) A term toto-partially coinclusive,
and a term parti-totally coexclusive, of
a third, are toto-partially coexclusive
of each other.
VI. — Objections to the Doctbine of a Quantified Predicate Con-
sidered.
(a) GENERAL.
HATERIAL and formal. — THEIR DISTINCTION.
But it is requisite, seeing that there are such misconceptions prevalent on
the point, to determine precisely what is the formal which lies within the
jurisdiction of Logic, and which Logic guarantees, and what the material which
lies without the domain of Logic, and for which Logic is not responsible. This
is fortunately easy.
Logic knows — takes cognizance of — certain general relations; and from
these it infers certain others. These, and these alone, it knows and guarantees ;
and these are formal. Of all beyond these forms or general relations it takes
no cognizance, affords no assurance ; and only hypothetically says, — If the
several notions applied to these forms stand to each other in the relation of
6|d APPENDIX.
tlteee forms, then so and so is the result Bat whether these notions arte rightly
ajjplied, that is, do or do not bear a certain reciprocal dependence, of this
I^>{j:ic, as IvOgic, knows nothing. Let ABC represent three notions, A con-
(.lining B, and B containing C; in that case Logic assures us that C is a part
of B, and B a part of A ; that A contains C ; that C is a part of B and A.
Xow all is formal, the letters being supposed to be mere abstract sj-mbols. But
if we apply to them — fill them up by — the tliree determinate notions, —
Animal, — Man, — Negro, we introduce a certain matter, of which Logic is
not itself cognizant ; Lo^c, therefore, merely says, — If these notions hold
to each other the relations represented by ABC, then the same results will
follow ; but whether they do mutually hold these relations, — that, as material,
is extra-logical. Logic is, therefore, bound to exhibit a scheme of the forms,
that is, of the relations in their immediate and mediate results, which are deter-
mined by the mere necessities of thinking, — by the laws of thought as thought ;
but it is bound to nought beyond this. That, as material, is beyond its juris-
diction. However manifest, this has, however, been frequently misunderstood,
and the material has been currently passed off in Logic as tha formal.
But further, L(^ic is bound to exhibit this scheme full and unexclusive. To
lop or limit this in conformity to any circumstance extrinsic to the bare condi-
tions, the mere form, of thought, is a material, and, consequently, an illegiti-
mate curtailment. To take, for instance, the aberrations of common language
as a model, would be at once absurd in itself, and absurd as inconsistent even
with its own practice. And yet this double absurdity the Logic now realized
actually commits. For while in principle it avows its allegiance to thought
alone, and in part it has overtly repudiated the elisions of language; in part it
has accomnKxlateil itself to the usages of speech, and this also to the extent
from which even (jiammar has maintained its freedom. Grammar, the science
proper, the nomology, of language, has not established ellipsis as a third law
beside Concord and Giovemment ; nor has it even allowed Concord or Govern-
ment to be superseded by ellipsis. And why ? Because tlie law, though not
externally expressed in language, was still internally operative in thought.
J^ogic, on the contrary, the science proper, the nomology, of thought, has
established an imperative ellipsis of its abstract forms in conformity to the
precarious ellipses of outward speech ; and this, although it professes to look
exclusively to the internal process, and to explicate, — to fill up what is implied,
but not stated, in the short cuts of ordinary language. L<^c has neglected,
— withheld, — in fact openly suppressed, one-half of its forms (the quantifica-
tion of the predicate universally in affirmatives, particularly in negatives),
btK.'auso these forms, though always operative in thought, were usually passed
over as superfluous in the matter of expression.
Thus has Logic, the science of the form, been made hitherto the slave of
the matter, of thought, both in what it has received and in what it has rejected.
And well has it been punished in its servitude. More than half its value has
at once been lost, confusion on the one hand, imperfection on the other, it& lot ;
disgust, contempt, comparative neglect, the con8e<iuencc. To reform Logic, we
must, therefore, restore it to freedom; — emancipate the form from the matter;
— wc must, 1°, Admit nothing material under the name of formal, and, 2°,
APPENDIX. 541
Reject nothing formal under the name of material. When this is done, Logic,
stripped of its accidental deformity, walks forth in native beauty, simple and
complete ; easy at once and useful.
It now remains to show that the quantities of the Predicate denounced by
logicians are true logical forms.
*******
The logicians have taken a distinction, on which they have defended the
Aristotelic prohibition of an overt quantification of the predicate 5 the distinc-
tion, to wit, of the formal, in opposition to the material, — of what proceeds vi
formce, in contrast to what proceeds vi materice. It will be requisite to deter-
mine explicitly the meaning and application of these expressions ; for every
logical process is formal, and if the logicians be correct in what they include
under the category of material, the whole system which I would propose
in supplement and correction of theirs must be at once surrendered as
untenable.
In the first place, the distinction is not established, in terms at least, by
Aristotle. On the contrary, although the propositional and syllogistic relations
which he recognizes in his logical precept be all formal, he, as indeed all
others, not unfrequently employs some which are only valid, say the logicians,
171 materice, and not ratione forma;, that is, in spite of Logic.
But here it is admitted that a distinction there truly is ; it is, consequently,
only necessary, in the second place, to ascertain its import. What then is
meant by these several principles ?
The answer is easy, peremptory, and unambiguous. All that is formal is
true as consciously necessitated by the laws of thought ; all that is material is
true, not as necessitated by the laws of thought, but as legitimated by the
conditions and probabilities discoverable in the objects about which we chance
to think. The one is a priori, the other a posteriori; the one is necessary,
the other contingent; the one is known or thought, the other unknown or
unthought.
For example : if I think that the notion triangle contains the notion trilateral,
and again that the notion trilateral contains the notion triangle ; in other words,
if I think that each of these is inclusively and exclusively applicable to the
other ; I formally say, and, if I speak as I think, must say — All triangle is all
ti-ilateral. On the other hand, — if I only think that all triangles are trilateral,
but do not think all trilaterals to be triangular, and yet say, — All triangle is all
trilateral, the proposition, though materially true, is formally false.
Again, if I think, that this, that, and the other iron-attracting stones are some
magnets, and yet thereon overtly infer, — All magnets attract iron ; the infer-
ence is formally false, even though materially not untrue. Whereas, if I think
that this, that, and the other iron-attracting stones are all magnets, and thence
conclude, — All magnets attract iron; my conclusion is formally true, even
should it materially prove false.
To give the former example in an abstract notation : If I note C : " : V,
I may formally convert the proposition and state T : ■! : C. But if I note
C : 11 r, I cannot formally convert it, for the F may mean either : F or
:42
APPENDIX.
, r ; and if I do, the product may or may not be true, according as it is acci-
dentally applied to this or that particular matter. As to the latter example :
C, — : (m m' m", etc.) : m : T
II :ia.ika&i-, '
This syllogism is formally legitimate. But, to take the following antecedent :
this, if formally drawn, warrants only, (1), a particular conclusion ; and if, (2),
a universal be drawn, such is logically null :
C,-
1.
2.
(m m' m", etc.) :
,r
This being the distinction of formal and material, — that what is formally
true, is true by a subjective or logical law ; — that what is materially true, is
true on an objective or extra-logical condition ; the logicians, with Aristotle at
their head, are exposed to a double accusation of the gravest character. For
they are charged : — 1°, That they have excluded, as material, much that is
purely formal. 2°, That they have included, as formal, much that is purely
material. Of these in their order.
1°, I shall treat of this under the heads of Affirmative and of Negative
propositions.
Of the four Affirmative relations of concepts, as subject and predicate ; to
wit — 1. The Tolo-lotal ; 2. The Toto-partial ; 3. The Parti-Toicd ; 4. The
Parti-Partial ; one half (1, 3) are arbitrarily excluded from logic. These are,
however, relations equally necessarj', and equally obtrusive in thought, with
the others ; and, as formal realities, equally demand a logical statement and
consideration. Nay, in this partial proceeding, logicians are not even self-con-
FJstent. They allow, for example, the toto-partial dependency of notions, and
they allow of their conversion. Yet, though the terms, when converted, retain,
and must retain, their original relation, that is, their reciprocal quantities ; we
find the logicians, aft^'r Aristotle, declaring that the predicate in affirmative
propositions is to be regarded as particular ; howbeit, in this instance, where the
tuto-purlial is converted into the parti-total relation, their rule is manifestly
false. When I enounce, — All man is animal, I mean, — and the logicians do
not gainsay me, — All man is some animal. I then convert this, and am allowed
to say, — Some animal is man. But I am not allowed to say, in words, though
I say, indeed must say, in thought, — Some animal is all man. And why ?
Simply because there is an old traditionary rule in Logic which prohibits us
in all cases, at least of affirmative propositions, to quantify the predicate univer-
sally; and to establish a'reason for this exclusion, the principle of materiality
has been called in. But if all is formal which is necessitated by thought, and
if all that is formal ought to find an expression in Logic, in that case the uni-
versal quantification of the notion, when it stands as predicate, may be, ought,
indeed, on demand, to be, enounced, no less explicitly than when it stood as
1 For an explanation of the notation here employed, in reference to Syllogism, see
Apiteiidix XI. — Eu.
APPENDIX. 643
subject. The quantification is no more material on tlie one alternative than
on the other ; it is formal in both.
In like manner, the toto-total relation is denounced. But a similar exposi-
tion shows that notions, thougbt as reciprocating or coequal, are entitled, as
predicate, to have a universal quantification, no less than as subject, and this
formally, not materially.^
In regard to the four Negative relations of terms, — 1. The Toto-total, — 2.
The Toto-partial, — 3. The Paiti-total, — 4. The Parti-partial ; in like manner,
one half, but these wholly different classes (3, 4), are capriciously abolished. I
say capriciously ; for the relations not recognized in Logic are equally real in
thought, as those which arc exclusively admitted. Why, for example, may I
say, as I think, — Some animal is not any man ; and yet not say, convcrtibly, as
I think, — Any man is not some animal f For this no reason, beyond the caprice
of logicians, and the elisions of common language, can be assigned. Neither
can it be shown, as I may legitimately think, — Some animal is not some animal
(to take an extreme instance), that I may not formally express the same in the
technical language of i-easoning.
In these cases, to say nothing of others, the logicians have, therefore, been
guilty of extruding from their science much that is purely formal ; and this on
the untenable plea that what is formal is material.
(6) SPECIAL.
Two objections have been taken to the universal quantification of the pred'
icate. It is said to be — 1°, False ; 2°, If not false, useless.
I. The first observation may be subdivided into two heads, inasmuch as it
may be attempted to establish it, a), on material; b), on formal, grounds. Of
these in their order : —
a). This ground seems to be the only one taken by Aristotle, who, on three
(perhaps on four) different occasions denounces the universal quantification of
the predicate (and he but implicitly limits it to affirmative propositions) as
" always untrue." ^ The only proof of this unexclusive denunciation is, how-
ever, one special example which he gives of the falsity emerging in the propo'
sition, — All man is all animal. This must be at once confessed false ; but it is
only so materially and contingently, — argues, therefore, nothing for the formal
and necessary illegitimacy of such a quantification. As extra-logical, this
proof is logically incompetent ; for it is only because we happen, through an
external knowledge, to be aware of the relations of the concepts, man and
animal, that the example is of any import. But, because the universal quanti-
ficatioa of the predicate is, in this instance, materially false, is such quantifica-
tion, therefore, always formally illegal ? That this i^ not the case, let us take
other material examples. Is it, then, materially false and formally incompe-
tent to think and say, — All human is all rational, — All rational is all risible, —
1 It is hardly requisite to notice the blun- nounced by the acuter logicians, when they
dering doctrine of some autliors, tliat the have chanced to notice the absurdity. See
predicate is materially quantified, even when Fonseca, Insiit. Dial. 1. vi. c. 20.
predesignated as universal. It is sufficient to 2 See p. 546. — Kd.
observe that this opiuion is explicitly re-
544
APPENDIX.
AU risible vi all capab'e of a'lmiraiion, — All trilateral is all triangular, — ,421
triangular is all figure with its angles equal to two right angles, etc. ? Or, em-
ploying Aristotle's material example, is it untrue, as he asserts, to say, — Some
animal is all man ; and this either collectively, — A part of the class animal i.<
the whole of the class man, — or distribuiively, — Some several animal is ever^
several man ?
But the absurdity of such a reasoning is further shown by the fact, that if it
were cogent at all, it would equally conclude against the validity of the uni-
versal quantification of the subject For this proposition is equally untrue
(employing always Aristotle's own material example), — All animal is man.
After this, it may the less surprise us to find that Aristotle silently abandons
his logical canon, and adheres to truth and nature. In fact, he fre(}uently does
in prartice virtually quantify the predicate, his conmion reasonings often pro-
ceeding on the reciprocation or coextension of subject and predicate. Nay,
in his logical system, he expressly rccc^nizes this coextension ; unless, indeed,
we overtly supply the quantification of the predicate, his doctrines of Induc-
tion and of Demonstration proper have no logical notation ; and, unless we
covertly suppose it, they are actually arrested. His definitions of the Univer-
sal, as severally given in his Prior and Posterior Attalylics, are, in this respect,
conllictive. In the former, his universal (known in the schools as the Universale
Prioristicum) explicitly forbids, whereas the latter (the Universale Posterior-
isticum of the schoolmen) implicitly postulates, the quantification of the
predicate.
b).. The defect in the polemic of their master was felt by his followers.
They, accordingly, in addition to, but with no correction of, Aristotle's doc-
trine, argue the question on broader ground ; and think that they disprove the
formal validity of such quantification by the following reasoning. Overlooking
the case, Avhere the subject is particularly, the predicate universally, quanti-
fied, as in the instance I have just given, they allege the case of Avhat are
called reciprocating propositions, where both subject and predicate are taken
in their utmost extension, vi materia, as subsequent logicians^ say, but not
Aristotle. In this case, then, as in the example. All man is all nsible, they
assert that the overt quantification of the predicate is inept, because, the all as
applied to the subject being distributively taken, every individual man, as
Socrates, Plato, etc., would be all (that is, the whole class) risible. This ob-
jection is only respectable by authorit;^', through the great, the all but unex-
clusive, number of its altegers ; in itself it is futile.
Terms and their quantifications are used either in a distributive, or in a col-
Iwlive, se!»se. It will not be asserted that any quantification is, per se, neces-
sirtly collective or necessarily distributive ; and it remains to ascertain, by rule
an<l relation, in which signification it is, or may be, employed. Now a general
rule or postulate of logic is, — That in the same logical unity (proposition or
syllogism), the same term or quantification should not be changed in imjwrt*
If, therefore, we insist, as insist we ought, that the quantification here, all,
should be used in the sam^ proposition in the same meaning, that is, as applied
1 [Sci', for example, Pacius, //i An. Prior, L. i. c. 6, p. 134.
9, and above, p. 527, note 1, sub. fin.]
Alexander, In An. Prior, L. i. c.
2 Seep. 612.— Ed.
APPENDIX. 545
to the one term, collectively or distributivelyj it should be so applied likewise
to the otlier, the objection fails. Thus taken collectively : — All (that is, the
whole class) man is all (that is, the whole class) risih'e, the proposition is valid.
Again, taken distributively : — All (that is, every several) man is all (that is,
every several) risible, the proposition is, in like manner, legitimate. Jt is only
by violating the postulate, — That in the same logical unity the same sign or
ivord >>hould be used in the same sense, that the objection applies ; whereas, if the
postulate be obeyed, the objection is seen to be absurd.
It is hardly necessary to say anything in confutation of the general doctrine,
that in Reciprocating propositions the predicate is taken in its full extent, vi
materice. In the first place, this doctrine was not promulgated by Aristotle;
who, frequently allowing, — frequently using, — such propositions, implicitly
abandons the rule which he explicitly lays down in regard to the non-pre-
designation of the predicate by a universal. In the second place, apart from
authority, such doctrine is in itself unfounded. For as form is merely the ne-
cessity of thought, it is as easy to think two notions as toto-totally coinciding,
(say, triangle and trilateral), as two notions toto-partially and parti-totally co--
inciding (say, triangle and figure). Accordingly, we can equally abstractly
represent their relations both by geometric quantities (lines or figures),,
and by purely logical symbols. Taking lines: — the former | ; the
latter ( . Taking the symbols, the former C : m < : T ; the latter
A, ■■ I — : B. But if the reciprocation were determined by the mere matter,.^
by the object contingenfly thought about, all abstract representation would bo^
impossible. So much for the first objection, — that the universal quantification i
of the predicate would, at least in affirmative propositions, be false.
11. As to the second objection, that such quantification would be useless and
superfluous, dicorderly, nay confusive, this only manifests the limited and one-
sided view of the objectors, even though Aristotle be at their head.
Is it useless in any case, theoretical or practical, that error be refuted, truth
established ? And in this case —
1°, Is it disorderly and confusive that the doctrine of Exponibles, as they-
are called, should be brought back from anomaly and pain to ease and order;,
that propositions Exclusive and Exceptive, now passed over for their difficulty,
and heretofore confessedly studied as " opprobria and excruciations," should
he shown to be, hot merely reducible by a twofold and threefold tortuosity,
through eight genera and eight rules, but simple, though misunderstood, mani-
festations of the universal quantification of the predicate ?^
2°, Is it useless to demonstrate that every kind of proposition may be con-
verted, and not some only, as maintained by Aristotle and the logicians ? And
is it disorderly and confur^ivc, in all cases, to abolish the triple (or quadruple))
confusion ift the triple (or quadruple) processes of Conversion, and to show,,
that of these proeesees there is only one legitimate, and that, the one simple of.
the whole ?
3", Is it disorderly and confusive to abolish the complex confusion of Mood
And Figure, with all their array of rules and exceptions, general and special ;,
and thlis to recall the science of reasoning to its real tmity ?
gg 1 See p. 617. —Ed.
.'>46
APPENDIX.
4°, Is it useless and superfluous to restore to the science the many forms
of reasoning which had erroneously, ineffectually, and even inconsistently,
been proscribed ?
5°, Is it useless or superfluous to prove that all judgment, and, consequently,
all reasoning, is simply an equation of its terms, and that the difference of sub-
ject and predicate is merely arbitrary V
6°, In fine, and in sum, is it useless or superfluous to vindicate Logic against
the one-sided views and errors of logicians, to reconcile the science with truth
and nature, and to reestablish it at once in its amplitude and simplicity ?
VII, — Historical Notices of Doctrine of Quantified Fredicatk.
(a) ASISTOTLB.
It will be sufficient to make one extract from Aristotle in illustration of his
doctrine upon this point, and I select the following passage from his Categories^
c. v., § 7.
" Further, the primary substances [vpSnai ohaiai, — individual existences], —
because they are subjects to all the others, and as all the others are predicated
of, or exist in, them, — are, for this reason, called substances by preeminence.
And as the primary substances stand to all the others, so stands the Species to
the Genus. For genera are predicated of species, but not, conversely, species of
genera ; so that of these two, the species is more a substance than the genus."
Ammonius, who has nothing in his Commentary on the Categories relative to
the above passage of Aristotle, states, however, the common doctrine, with its
reasonsj in the following extract from his Commentary on Porphyry's Introdxic-
tion (f 29, ed. Aid. 1546).
" But confining ourselves to a logical consideration, it behooves us to inquire,
— of these, which are subject to, which predicated of, the others ; and to be
aware that Genera are predicated of Differences and Species, but not con-
versely. These, as we have said, stand in a certain mutual order, — the genus,
the difference, and the species ; the genus first, the species last, the difference
in the middle. And the superior must be predicated of the inferior ; for to
predicate the inferior of the superior is not allowable. If, for example, we
say, — All man is animal, the proposition is true ; but if we convert it, and say, —
All animal is man, the enouncement is false.* Again, if we say, — All horse is
irrational, we are right ; but if conversely we say, — All irrational is horse, we
are wrong. For it is not allowed us to make a subject of the accidental.
Hence it is incompetent to say that Animal is man, as previously stated."
[^Categ. ch. ii., § 1.
" When one thing is predicated of another as of its subject, all that is said
[truly] of the predicate will be said [truly] also of the subject Thus man is
1 The converse of a true proposition is al-
ways true; but the false propositions which
are here given, as conversions of the true,
are not conversions at all. The true proposi-
tions, if explicitly stated, SiTe, — Alt man is
some animal, and, All horse is some irrational.
Convert these, — Some animal is all man, and,
Some irrational is all horse ; the truth remains,
but the one-sided doctrine of the logicians li
exploded.
APPENDIX. 647
predicated of this and that man,^ and animal of man ; animal will therefore be
predicated of this and that individual, for this and that individual is both man
and animal."
De Interpret., c. vii., § 2-4 ; see also c. x.
" To enounce something of a universal universally, I mean as. All or every
man is white, No man u> white To enounce something of universals not
universally, I mean as, Man is while, Man is not tchite : for whilst the term man
is universal, it is not used in these enouncements as universal. For all or every
(iros) does not indicate the universal [itself], but that [it is applied to a sub-
ject] universally. Thus, in reference to a universal predicate, to predicate
the universal, is not true. For no affirmation is true in which the universal is
predicated [of a universal predicate], as, All or every man is all or every ani-
vial." (See Ammonius, Boethius, Psellus, Magentinus, etc.)
Pritjr Analytics, Bk. I. c. 27, § 9. " The consequent [i. e. the predicate] is
not to be taken as if it Avholly followed [from the antecedent, or subject, ex-
clusively]. I mean, for example, as if all [or every"] animal [were consequent]
on man, or all [or every] science on music. The consequence simply [is to be
assumed], as in our propositions has been done ; to do otherwise (as to say that
all [or evei-y] man ts- all [or every] animal, or tha,t justice is all [or every] good),
is useless and impossible ; but to the antecedent [or subject] the all [or ex'ery]
is prefixed."
Posterior Analytics, B. I. c. xii., § 10. " The predicate is not called aZ/" [or
every] ; [that is, the mark of universality is not annexed except to the subject
of a proposition].
In refutation of Aristotle's reasoning against the universal predesignation
of the predicate — it will equally disprove the universal predesignation of the
subject. For it is absurd and impos-siblc to say. All animal is man ; All (every)
immortal iv the soul; All pleasure is health ; All science is music ; All motion is
pleasure.'^ But in point of fact such examples disprove nothing ; for all universal
predesignations are applicable neither to subject rtor predicate, nor to both sub-
ject and predicate — are thoughts, not things ; and so are a\\ j^redesignations ;
therefore, etc. It is only marvellous that such examples and such reasoning
could satisfy the acutest of intellects ; that his authority should have imposed
on subsequent logicians is less wonderful.*]
1 [For the rls here, as elsewhere, denotes of the definition elevated into a two-fold
the individuum signatum, not the individumn axiom, the esse t'n toto, etc., and diet de omni,
vagvm.] etc., toward the conclusion of the first chap-
2 Examples from 'Wegelin, In Greg. Ane- ter of the first boolc of the Prior Analytics,
ponymi Comp. Phil. Synt. L. iv. c. 1, p. 473; Tb S4 4v o\<i) tlyou erepov kripw Kai rb
L. vi. c. 1, p. 673. Kara irayThs Korriyoftfia^ai bartpov dd-
3 And here I may correct an error, as I con- repov ravT6v iffTiv. This, with its ambi-
ceive it to be, which has descended from the guity, may be thus literally, however awk-
' oldest to the most recent interpreters of the wardly, translated : — " But [to say] that one
Organon, and been adopted implicitly by thing it in a uiAoZe otAer, and [to say] that one
logicians in general. It is found in Alexan- thing is predicated of all another, are identicai."
der and Ammonius, as in Trendelenburg, — Now, the question arises, — What does
Saint-Hilaire, and Waitz; nor indeed, as far Aristotle here mean by "a whole other?'" for
afi I know, has it ever been called in question it may signify either the class or higher no-
during the interval. It regards the meaning tion under which an inferior concept cornea.
548
APPENDIX.
Quantification of Predicate — Aristotle.
1. Admits that syllogism mental not oral (An. Posl.l. 10). This to be borne
in mind.
2. That individual is never predicated (Cat. c. 2), refuted by reciprocation of
singular (An. Pr. ii. 23, § 4).
3. That affirmative universal not [to] be added to predicate, incompatible with
what he says of reciprocation (in ^4)1. Pr. ii., cc. 22 and 23 alibi). That his
custom to draw universal conclusions in Third Figure and affirmative in
Second* with allowance of simple conversion in certain universal affirma-
tives.
4. That particular not in negative predicate, absurd in oi «-os, non omnis.
Aristotle's doctrine of Prcdcsignation.
1"*, How can Aristotle, on his doctrine, make universal terms taken indif-
or the inferior concept itself, of which, as of
a subject, the higher is predicated. Tlie for-
mer is tlie sense given by all the commenta-
tors; the latter, the sense which, I am confi-
dent, was intended by Aristotle.
There are only two grounds of interpreta-
tion. The rule must be expounded in cousi:^
tency — 1°, With itself; 2°, Must be with the
analogy of Aristotelic usage.
P. On the former ground, the ecmman
doctrine seems untenable; for what Arislotle
declares to be identical, by that doctrine be-
comes diflferent, nay, opposed. An inferior
concept may be in a higher whole or class,
either partially or totally; and tlie definition
on the prevalent interpretation virtually runs
— *'To say that one thing is all or part in the
whole of another, and to say that this other
is predicated of it nnexclu.«ivcly; are convert-
ible." Had Ari.stotle, therefore, u.sed the ex-
pression in the signification attributed to him,
he must, to avoid the contradiction, have
raid — TJ> 8i itaf iripov iy 8Xo> tlyai irtpa,
K.T.\. (" But to say that one thing is all >a
a whole other," etc.)
2°. On the second ground, it may, however,
be answered, that the ambiguity of the word,
R8 it stands, is superseded, its signification
being determined by other passages. I join
i»ne; and on this ground am well content to
let the question be decided.
In flie first place, the meaning I attribute
to the expression, '^whole oth^r" — that is,
whole SHbject or Inferior notion — is, in short,
h> nfrict conformity with Aristotle's ordinary
langunge. There are, I admit, sundry pas-
rages in his logical writings where the term
voAolf is clearly used as synonymous with class,
or higher notion ; as, to limit ourselves to the
Prior Analytics, In Hook I. iv. § 2; and II. i.
t 4. But, every single text, in which the term
ftkoU appears in this relation, Is overruled by
more than five others, hi whicli H is no less
clearly applied to denote the totaiity of a lower
noiion, of which a higher is predicated —
pasj-ages in winch the word whole {o\os) is
itsed conveilibly with all {"Kai). See for ex-
ample. An. Pr. JI ii. i 5. » 16— iii. i 5, } 7
{bis ), i 14. ^ 15 — iv. i 6 (6m.), § 8, i 10, i 12
{his ) — xxii i 1. i 8 — xxiii. ^ i.
Lnt in the si-cond place (and this is directly
cobversive of the conuter-opinion, even iu
tl;u prii!ci])al of the few passages where the
term iciioU is u..oil lor class), the lower notion
mny bo in or under the higher, only particu-
larly; and this manifestly shows that Aris-
totle could not possibly mean, by merely say-
ing that one thing is another, as in a cla.ss,
that it is so uneidusivtly, or universally. Com-
pare .in. Pr. I iv. {( 2, 3, 10. On this inter-
pretation, Darii and Feno would then b(!
annulled; a special result which ought to
have startled the logicians into a doubt of
the accuracy of the received doctrine in gen-
eral. (See. instar omnium, Facias, in his rela-
tive Kotes and Commentary.)
That doctrine must, therefore, be aban-
doned, and the rule, reduced to a defini'ion,
read iu the following signification: — "But
to say that one thing is in the whole of anotlier,
as in o iub;ect, and to preJicate one thing tmiver-
scUiy oj another, are merely various expression:!
of the same meaning." This, in tact, is juft
the preliminary explanation of the two orUi-
nary modes of stating a proposition, subsi--
quently used by Aristotle. Here, in bot^i
convertibles, he descends from extension to
comprehension, from the predicate to the
subject; and the ingenious exposition by the
commentators, old and new, of the inverse
intention of tlic philosopher in the two
clauses, must be regarded as erroneous.
1 8«ep. 681. — Ed
¥
APPEMDIX. d40
ferently, or without predesignation, be tantamount to particulars ? (^An. Prior,
I. c. 4, § 13 ; Org. Pacii, p. 135, alibi).
2°, An. Prior, I. c- 27, § 7, He says, as elsewhere, " A proposition being in-
definite £preindesignate], it is not clear whether it be universal ; when, however,
it is definite [predesignate], that is manifest." Contrast this statement with hii
doctrine of the all.
3°, There are syllogisms in Aristotle which are only valid through the quaoi
tity of the predicate.^
4", Aristotle requires, though he does not admit, the universal predesigna-
tion of the predicate in his syllogism of Induction. (Vide An. Prior, L. ii. c.
23, § 4 ; Organon Pacii, p. 399. Compare also his doctrine, p. 396.)
(b) ALEXANDER APHRODISIENSIS.
Alexander Aphrodlsiensis, in his commentary on the first book of the Prior
Analytics, in reference to the second passage of Aristotle, states as follows :
*' And in the book of Enouncement Aristotle explains why he there says : — •
* that to predicate the universal of a universal predicate is not true ; for there
will be no proposition, if in it we predicate the universal of the universal, as,
All man is all animal.' He repeats the same also here ; showing how it is
useless to attempt thus to express the consecution [of higher from lower
notions] ; and adds, that it is not only useless, but impossible. For it is impos-
sible that all men should be all animal, as ^useless to say (axfiv<rroy etirtiy must
have dropt out)], that all man is all risible. We must not, therefore, apply the
all to the subsequent [or predicate], but to that from which it follows [or sub*
jectj. For man .is to be taken universally, as that from which animal follows,
supposing this to be the consequent of all man. Thus shall we obtain a stock
of universal propositions. The process is tiie same in making man the con8e>
(jueut on its proper all; but man is not consequent on all biped, but on all
rational.
" The words, ' aa we express ourselves,' mean — as we express ourselves in
common usage- For we say, that all man is simply animal, and not all animal,
and that all pleasure is natural, not all natural ; prefixing the aU, not to the
consequent, but to the subject from which the predicate follows." (Edd. Aid.,
f. 100 a ; Junt., f. 122 a ; compare Aid., f. 86 a ; JunL, f. 105 a.)
(c) AJlUOmUS HBRMIJS.
Ammonlus Henniae, In de Jnterp. c. vii. § 2. (Aldine editions, of 1503, sig.
C. vii. 59, of 1546, fi". 70, 74.)
" In these words Aristotle inquires, — Whether, as the annexation of the
affirmative predesignation (irp<j<ThopuyfjL6s) to the subject constitutes one distinct
class of propositions, the same annexation to the predicate may not, likewise,
constitute another; and he answers, that the supposition is absolutely groun '.-
less. Thus the enouncement — all (or every) man is all (or every) animal
(vais iufApttros T&r (»»" ^<""«)> ^serts that each man is all animal, as horse, ox, etc
1 Seep. 681. — Ed.
550
APPENDIX.
But this proposition is impossible ; as is shown by Aristotle in his here omitting
the word ' true.' For no affirmation can be true in which the universal is
predicated of a universal predicate ; that is, in which the universal predesignate
is added to a universal predicate ; as when we say that man (of whom all, or,
as he says, universally, animal is predicated) is not simply animal, but all
animal. He, therefore, teaches that such an affirmation, as utterly untrue, is
utterly incompetent
" Neither does Aristotle allow the predesignation some to be annexed to the
predicate, that propositions may, thereby, become true always or occasionally.
For logicians (as they do not propose to tliemselves every superfluous variety
of enunciation) are prohibited from considering propositions (not only thoje
always true or always false), but those which express no difference in reference
to necessary or impossible matter, and afford us absolutely no discrimination of
truth from falsehood. Thus, particular propositions, which may be alternatively
true and false, ought not to have a prodesignated predicate. For in a proposi-
tion which has all their power, without any predesignation of its predicate,
why should we prefer to the simpler expression that which drags about with
it a sui>erfluous additament ? Why, for example, instead of — All man is some
animal [I read, n ^Sioy], or. All man in not all animal,^ sliould we not say, — AU
man w. animal, and in place of All man is no stone, not say, — All man is not
tlone : or, what is a simpler and more natural enouncement still, — No man
is stone ?
" And when we find some of the ancients teaching that the particular affirma-
tive predesignation is to be connected with the predicate, as when Aristotle
himself styles the soul a certain (some) entelechy (ivrfXtxttdf rtva), and Plato,
rhetoric, a certain (some) experience (fus-tipcW tii/o) ; it is to be observed that
the some is there added for the sake of showing, that the predicate is not con-
vertible Avith the subject, but is its genus, and requires the adding on of certain
differences in order to render it the subject's definition.
" But, add they, is not the reasoning of Aristotle refuted by fact itself, seeing
that we say, All man is capable of all science : thus truly connecting the uni-
versal predesignation with the universal predicate? The answer is this: —
that, in truth, it is not the predicate to which we here annex the all. For what
is predicated, is what is said of the subject. But what is here said of mail iv<
not that he is science, but that be is capable of science. If, therefore, the <M
were conjoined with the capable, and the p7X)position then to remain true, as
when we say — all man is all capable of science ; in that case the reasoning of
Aristotle would be refuted. But this proposition is necessarily false. It, in
fact, asserts nothing less than that of men, each individual is all the kind : —
that Socrates is not Socrates only, but also Plato, Alcibiades, and, in short,
every other man. For, if all man is all capable of science, Socrates being
one of the all, is, therefore, himself all capable of science; so that Socrates
will be Plato, Alcibiades, etc., since they also are capable of science. For if
1 It will be observed that Ammonias does
not attempt an equivalent for this proposi-
tion. In fact it is impossible on the common
or Aristotclic doctrine; and this impoesibilitjr
itself ought to have opened his eyes upon the
insufficiency of the view be maintained.
APPENDIX. 551
Socrates be not, at once, Plato, Alcibiades, etc., neither will he be all capable
of science.
" Now, that we ought not to prefix the universal affirmalive predesignation
to the predicate (whether the predicate be more general than the subject, as
All man is all animal, or whether they be coadequate, as All man is all risible),
this is manifest from what has been said. Even when the terms ai-e coadequate
or reciprocating, the proposition runs into the absurd. For, declaring that
all man is all risible, it virtually declares that each individual man is identical
with all men ; that Socrates, in that he is a man, Is all risible, consequently, all
man
" But why is it that the predicate is intolerant of the predesignation all,
though this be akin to the counter-predesignation no or none ? Is it because
the affirmative predicate, if predicated universally, tends always to contain
under it the subject, and this not only when itself coadequate with the subject,
but when transcending the subject in extension ; while, moreover, through a
participation in its proper nature, it is suited to bind up and reduce to unity
the multitude of individuals of which the subject is the complement ? For, as
Aristotle previously observed — ' the all does not indicate the universal, but
that [the universal predicate Inheres in, or is attributed to, the subject] uni-
versally.' If, therefore, the affirmative predicate thus tend to collect into one
what are by nature distracted, in virtue of having been itself previously recog-
nized as simple ; in this case, the all [superadded to this universal predicate,
in fact] enounces not a unity, but a multitude of several things, — things which
it is manifestly unable to complicate Into reciprocity. But, on the other hand,
since what is negatively predicated of, is absolutely separated from, the subject;
we are, consequently, enabled to deny of the subject all under the predicate,
as in saying, All man is no stone. We may indeed condense this proposition,
and say more simply. All man is not stone; or, more simply still. No man is stone;
thus dispensing with the affirmative predesignation in a negative proposition."
fd; BOETUWS.
Boethius, In Librum de Interpretatione, editio secunda, et in textum lauda-
tum. Opera, p. 348.
" What he says Is to this purport : — Every simple proposition consists of two
terms. To these there is frequently added a determination either of univer-
sality or of particularity ; and to which of the two parts these determinations
are to be added, he expounds. It appears to Aristotle that the determination
ought not to be conjoined to the predicate term ; for In this proposition, Man is
animal — (Homo est animal). It is inquired whether the determination ought
to be coupled with the subject, so that It shall be — (Omnis homo animal
est) — All (or every) man is animal ; or with the predicate, so that it shall be —
(Homo omne animal est) — Man is all (or every) animal ; or with both the one
and the other, so that it shall be. All (or every) man is all (or every) animal
— (Omnis homo omne animal est). But neither of these latter alternatives is
competent. For the determination is never joined to the predicate, but ex-
clusively to the subject ; seeing that all predication is either greater than the
552 APPENDIX.
itubject, or equal. Thus in this proposition — All (or every) man is animal
(omnis homo animal est), animal [the predicate] is greater than man [the sub-
ject] ; and, again, in the proposition — Man is risible (homo risibilis est), risible
[the predicate] is equated to man [the subject] ; but tliat the predicate should be
less and narrower than the subject is impossible. Therefore, in those predicates
which are greater than the subject, as, for example, where the predication is
animal, the proposition is manifestly false, if the determination of universality
be added to the predicate term. For if we say, Man is animal {homo est
animal), we < ontract animal, which is greater than man, by this determination
to [an identity of extension with] man, the subject, although the predicate.
animal, may be applied not only to man, but to many other objects. Moreover,
in those [subjects and predicates] which are equal, the same occurs ; for if I
say. All (or even/) man if all (or every) ritible (omnis homo omne risibile est), —
in the first place, in reference to the nature of man itself, it is superfluous to
adject the determination ; and, again, if it be added to all several men, the
proposition becomes false, for when I say, All (or every) man u all (or every)
risible, by this I seem to signify that the several men are [each of them] all or
every risible, which is absurd. The determination is, therefore, to be placed
not to the predicate but to the subject. But the words of Aristotle are thus
reduced to the following import: — In those predicates which are universal, to
add to them aitf/ht universal, so that the universal predicate may be predicated uni-
versally, is not true. For this is what he says — " In the case of a universal
predicate " (that is, in a proposition which has a universal predicate), " to
predicate the universal itself universally, is not true." For in a universal
predicate, that is, which is universal and is itself predicated, in this case uni-
versally to predicate the predicate which is universal, that is, to adject to it a
determination of universality, is not true ; for it cannot be that any affirmation
riiould be true in which a universal determination is predicated of a predicate
universally distributed ; and he illustrates the conception of the matter by the
example, " All or every man is all (or every) anitnal (omnis homo omne animal
est)., of the incompetency of which we have already spoken."
Boethius, In Librum de luterpretatione, editio prima. Opera, p. 236. (Text
so wretchedly printed that the sense must be constituted by the reader.)
[^Aristotle, c. vii. § 4]. " ' In what is predicated as a universal, to predicate
the universal universally is not true.'
" In this sentence he instructs us what is the place to which the determina-
tion of universality should be rightly added. For he teaches that the univer-
sality, which we call the universal determination, is to be connected with the
subject term, never with the predicate. For were we to say — All (or every)
man is animal (omnis homo animal est), we should say rightly, annexing the all
(or every) to the subject, that is, to the term man. But if we thus speak — All
or every man is all or every animal (omnis homo omne animal e.'st), we should
speak falsely. He, thercfbro, docs not say this [in the words] — ' in what is
predicated as a universal,' as animal of man; for animal is universal, being
predicated of all or every man. [But he says] — To predicate this universal
itself, animal, to wit, universally, so that we enounce — All (or every) animal is
APPENDIX. 653
man (omne animal esse hominem), is not true; for he allows this to be rightly
done neither in these nor in any other affirmation.' He adds, therefore : —
* For no affirmation will be true in which a universal predicate shall be univer-
eally predicated, as All or every man is all or evert/ animal (omnis homo est omne
animal).'
" Why this hapjiens, I will explain in a few words. "Hie predicate is always
greater than the subject, or equal to it. Greater, as when I say, Man is animal
(homo animal est) ; here animal is predicated, man is subjected, for animal is
predicated of more objects than man. Again, it is equal when we thus speak
— Alan is rhtihle (homo risibilis est) : here man is the subject, risible the pred-
icate. But man and risible are equal ; for it is proper to man to be a risible
animal. But that the predicate should be found less than the subject, is impos-
sible. Is the predicate the greater ? Then,' to adject the universal to the
predicate, is false, as in the example he himself has given — All (or every) man
is all (or every) animal (omnif homo omne animal est). Is it equal ? Then, the
adjection is superfluous, as if one should say, All every man is all or every risible
(omnis homo omne risibile est). Wherefore, to predicate a universal predicate
universally is incompetent."
(e) AVERROES.
Averroes, Perihermenias, L. I., c. v.
" Propositions are not divided from the conjunction of the predesignatlon
(clausurae) with the predicate ; because the predesignatlon, when added to the
predicate, constitutes a false or a superfluous proposition : — False, as All or
every man is all (or every) animal (omnis homo est omne animal) ; superfluous,
as All (or every) man is some or a ccviain animal (omnis homo est quoddam ani-
mal)." Vide Conimbricenses, In Arist. Dial. ii. 158.
CO AlBERTUS MAQlfUS.
Albertus Magnus, Periherminias, L. I., Tractdtus, v. c. 1 {Op. ed- Lugd-
1651, t. I., p. 261),
[" Ly ' omnis ' non est universale, sed signum universalitatis, Quare ly
' omnis ' et hujusmodi signa distributiva non sunt universalia, secundum Avicen-
nam."] Hoc enim signum distributivum, quod est omnis, non est universale,
proprie loquendo ; sed est signum per quod stat pro particularibus universaliter
universale, cui tale signum est adjunctum. Causa autem, quare non sit univer-
sale, est : — quia, quamvis secundum grammaticum sit nomen appellativum, hoc
I The Coimbra Jesuits (Sebastianus Contus, his mighty Logic {art locum). With Boethius
1606) erroneously make Boctliius and Aver- he joins LcvigcrsouiUes ; — lio means li.e
roes oppoHe Aristotle, " thinking fliat the sign liabbi Levi Ben Gerson, of Catalonia, wiio
of uiiiverbalitv- may be annexed to tlie prodi- died at Perpignan in 1370, who wrote on
c«t« of It univoifal proposition when jt is Theology, I'hjlosophy, Mathematics, und
coextensive with the subject" tad locum ii., p. Logic. See Jocher v. Levi, from Bartoloccj
lo8) This, a mistake, has l)een copied by and Wolf,
their brother Jesuit, P. Vallius, of Rome, in
70
554
APPENDIX.
est, multis secundum naturae suas aptitudinem conveniens ; tamen est, secun*
dum fornaam, infinitum, nullam enim naturam unam dicit Propter quod omnis
naturae communis est distributivum. Universale autem est, quod est in multis
et de multis, suae naturae, suppositis. Ideo omnis, et nullus, et hujusmodi signa
universalia esse non possunt; sed sunt signa designantia utrum universale sit
acceptum universaliter vel particulariter, secundum sua supposita. Et haec
sunt verba Avicennae.
[" Quare signum universale non sit ponendum a parte praedicati.] In sub-
jecto universali signum distributivum ordinandum : quia per divisionem subjecti,
praedicatum partibus attribuitur subjecti, ut divisim participent id per praedica-
tionem, et non in praedicato ponendum : quia quum praedicatum formaliter sit
acceptum, non proprie dividitur, nisi alterius, hoc est, subjecti divisione : sed
inaequaliter redditur subjecto et partibus ejus. Unde id quod est universale,
praedicari potest, ut Omnis homo est animal; sed universale universaliter ac-
ceptum non potest praedicari : nulla enim vera affirmatio esse potest, in qua de
universali aliquo prsedicato predicetur sive praedicatio fiat ; quoniam universal-
iter sic patet, quod falsum est, Omnis homo est omne animal, ct si ponatur, quod
Nullum animal sit nisi homo. Cum enim hoino subjiciatur gratia partium suarum,
et praedicata fi)rmaliter accipiantur, oportet quod Quilibet homo esset omne ani-
mal, quod falsum est."
(f) LEVI BEN OERSOir.
Levi Ben Gerson (or Levi Gersonides), a Jewish philosopher, who died in
1370, at Perpignan, wrote commentaries on Averroes' Commentary upon the
logical books of Aristotle. The following is what he says on Averroes' doctrine
touching the quantification of the predicate, as it is found (f. 39) of the Venice
edition, in folio, of 1552,* of the works of Aristotle and Averroes: — "Al-
though it be not necessary that when the quantitative note is attached to the
predicate, this should be false or superfluous, seeing that it may be neither, as
when we say. All man is all rational ; and the same holds good in all other
reciprocating propositions; — nevertheless, as in certain matters it may so hap-
pen, Aristotle has declared that the quantitative note is not to be joined to the
predicate in any language. But it may be here objected, that if this be the
case, the quantitative note should not be annexed even to the subject, since
there too it may be either false or superfluous. Superfluous, — as when we
say, Some animal is rational. For the very same follows here, as if we simply
say. Animal is rational ; the some, therefore, is superfluous. False, — as when
we say. All animal is rational. The reason, therefore, assigned by Aristotle
why the quantitative note should not be annexed to the predicate, is futile, see-
ing that for the same reason it should not be connected with the subject. To
this we may answer : That the cause why the quantitative note is not usually
conjoined with the predicate, is, that there would thus be two qusesita at
once, — to wit, whether the predicate were afiirmed of the subject, and, more-
over, whether it were denied of everything beside. For when we say, All man
2 Not in the 8vo edition of these works. Venice, 15Q0.
APPENDIX. 555
is all rational, we judge that all man is rational, and judge, likewise, that ra-
tional is denied of all but man. But these are in reality two different quaesita ;
and therefore it has become usual to state them, not in one, but in two several
propositions. And this is self-evident ; seeing that a quaBsitum, in itself, asks
only — Does, or does not, this inhere in that V and not — Does this inhere in
that, and, at the same time, inhere in nothing else ? "
(h) THE MASTERS OF LOUVAIK.
Factdtatis Artium in Academia Lovaniensi Commentaria in Aristotelis Libros
de Dialectica (1535), Tr. iii. c. 1, p. 162, ed. 1547.
Speaking of the text in the De Interpretatione, the Masters, inter alia, allege :
" But if it be even elegantly said by a poet — ' Nemo est omnis homo,' —
' Non omnes omnibus artes ' — [proverb, ' Unus homo nuUus homo '], why may
we not contradict this aptly, howbeit falsely, — ' Aliquis est omnis homo ' ? Why
(they say) do you determine the predicate by the note of universality, seeing
that the quantity of the proposition is not to be sought from the predicate, but
from the subject ? We answer, because we wish to e.xpress a certain meaning
in words, which by no others can be done. But if the mark of universality
could only be employed in changing the quantity of propositions, it would
not be lawful to annex It to the part of the predicate. We have, therefore,
thought these few cautions requisite to evince that what Is condemned by these
critics for its folly, is not incontinently sophistical or foolish babbling. But as
to the universal rule which Aristotle enounces, — ' No affirmation will be true,*
etc., — it is sufficient if it hold good in the majority of cases ; whether the
predicate exceed the subject, as. All man is all animal, — be its equal, as, All
man is all risible, or its inferior, as, \^Some'] animal is all man. In a few cases,
however, the exception is valid; as, — This sun is every sun, One phoenix is all
phcenix,^nd some others. Nor are these futile subtleties, since reason herself
approves."
(i) Trrms and ridiger.
The only notice of these speculations of Titius^ which I have met with in
any subsequent philosopher (and I speak from an inspection of several hundred
1 [Titins, Ars Cogitandi, c. vi., has the fol- totam qnidem suam comprekensionem, non
lowing relative to the quantification of the vero extemionem. § 39 : E contrario in propo-
predicate: — } 36: "Licet autem Proposi- sitionibus negativis, licet particularibus, ple-
tiouum quantitas ex Subjecto sestimetur, at- rumque prsedicatum est vniversale, ac tam
tamen Prasdicatum non peuitus uegligendum secundum comprebensionem quam exten-
videbatur, ceu vulgo in hoc tractatioue fieri sionem guam totam, a subjecto removetur-
solet, nam et hujus quantitatem observasse § 41, Interim non putarem affirmationem vel
utile est, et crediderim et disquisitionis hujus negationem ipsam diversam illam praedicati
neglectu varios errores tam in doctrina Con- quantitatem necessario postulare, sed credi-
versionis, quam Syllogistica esse exortos, quos derim potius, id omne a diverse rerum et idea-
suis locis videbimus. j 37: Breviter itaque rum habitu oriri, aflSrmationi vero et nega-
observandum, in propositionibus afiirmativis, tioni prasdicati quantitatem esse velut indif-
licet uuiversalibus, prsedicatum plerumque ferentem. i 42: Nam plerumque prasdicata
esse particulare, tribuique subjecto secundum subjectis suntlatiora; quodsiigitur ilia cum
556
APPENDIX.
logical systems, principally by Germans), is his friend J^J^gWr's i '*f ^o» in hk
elaborate work, De Sensu Veri et Falsi, first published some eight yearssubee-
"quently (in 1709, but I have only the second edition of 1722}, attempts a
formal refutation of the heresy of a quantified predicate. It was only, how-
ever, after " the most manifest demonstrations of the falsehood of this novel
prejudice had been once and again privately communicated to his very learned
friend" (Titius?), that Ridiger became at length tired, as he expresses it, "of
washing a brick," and laid the polemic before the public. It was not certainly
the cogency of this refutation which ought to have thrown the counter opinion
into oblivion ; but this refutation, such as it is, though with nothing new, is
deserving attention, as presenting the most elaborate discussion of the question
to be met with, after Ammonius, and in modern times. But the whole ai^u-
ment supposes certain foundations ; and it will be sufficient to show that these
are false, to dispose of the whole edifice erected upon them. I ought to men-
tion, that it was Ridiger's criticism which first directed my attention to the
original of Titius.
" Origo autem hujus erroris neglectus notissimse acquivocationis signorum
omnis et quidam esse videtur, qua haec signa, vel collective sumi possunt, vel dis-
tributive. Priori modo, quantitas in praedicato concepta sensum quidem infert
non penitus absurd um, ca^terum propositionem constituit identicam et frus-
traneam." Ridiger then goes on to a more detailed statement of what he eup-
poses to be the groun<ls on which the erroneous opinion proceeds.^
First Case. — " Verbi gratia, Quoddam animal est omnis homo; hoc est. Species
qucedam anhnalif, homo nempe omne id, quod homo est : quod aliuin sensum,
habere nullum potest, quam, quod omnis homo sit homo : sic autem collective
Bumitur et signum snbjecti et signum praidicali." This objection is absunl, for
it is suicidal ; applying equalJy to the proposition which the objector holds for
good, and to that which he assails as bad. All man is (sovie^ animxil. Heie,
is not animal or some animal just a certain species of animal, and is not this
species, man, to wit, all that is man, and nothing else ? There is, consequently,
the same tautology in the one case as in the other ; and if we are blamed for
only virtually saying, by the former, All man is man, does the objector say a
whit more than this by the latter ? Ridiger goes on : " Quodsi vel alterum
signum, vel utrumque, distributive sumatur, semper absurdus erit propositionis
pensus."
l:is componas, non poterit non praedicatum
)ii«rticulRr« ind« «at«rgere, dum uuioa kd
i-'ubjccttini restringi nequit, scd ad aliaquoquQ
cxf*)iidi apfiim nmnet. { 43: A8t si praedica-
tum a subjecto rfmovca^, universale illud
urit, cum quicquid iu cjue vel comprelicnsione
vul extcnsiuiie i-'Kt ab lioc cejuii^atur, iitic iin-
miiiuit uuivcrsalitntuin, quod idem ab aliis
fulijecti»i quoque rvtnoveatur, ufim *i praedica-
tum aliix ctiam conveniat, turn quidem uni
Kubjecto non jtoteft dici univprsaliter tribu-
tiun, vorum ni de multis refretur. pote8t iiihil-
oniiuiis de corto Hiiniio subjecto unlver»iiliter
qnuqtio ne<;ari, S 4) : Quodsi habitus attributi
{Mirinittat, poterit uliquando propoaitio afiir-
mativa prscdicntum universale, et ncgativa
particulare habere; nihil enim obstat, quo
minus aliquando totum alteri jungere, vel
I>artem ab eodem removero queaa. ( 46: Uteo
itaque propositio: — Omnis homo, est risibilU,
habet pri«dicatum universale, °8i risibilitatem
pro liominis proprio habeas; eioiit hae, — JVni-
lus Turca fit homo (Soil. Chritiinnus), vel Qui-
dam mtilicvs no* est homo quidam, preedicatum
particulare continent, dum part) Folum com-
preheusionia et extenrionis removetur.'' For
the application, by Titius. of the principle of
a quantified predicate to the doctrine ot'Con-
ver(<ion. see above, pp. 628 fi29; and to the
theory of Syllo^iKm, see below, p. 60S, and
Appendix. X. — Ed]
1 Second Editioo, pp. 232, S02.
APPENDIX. J55T
Second Case. — " Verb! gratia, sumatur utrumque signum distributive, sensus
erit, Qubddam individuum animalis (v. g. Petrus), est omne individuum hominis
(v. g. Datms, Oedipus)." This is a still higher flight of absurdity; for, to re-
fute the proposition, it is first falsely translated into nonsense. Its true mean-
ing, both quantified terms being taken distributively, is : — All several men are
some several animals, or, Every several man is some several animal.
In these two cases, therefore, all is correct, and the objection from the
identity or absurdity of a quantified predicate, null.
Third Case. — " Sumatur signum subjecti distributive, signum praedicati col-
lective, sensus erit : Quoddam individuum animalis est universa species hominis."
Fourth Case. — " Sumatur, denique, signum subjecti collective, signum prrodi-
cati distributive, sensus erit : Qucedam species animalis, ut universale et prcedi-
cabile, est omne individuum hominis."
In regard to these last two cases, it is sufficient to refer to what has been
already said in answer to Ammonius (p. 549) ; or simply to recall the postulate,
tbat in the same logical unity (proposition or syllogism) the terms should be
supposed in the same sense. If this postulate be obeyed, these two cases are
inept, and, consequently, the objections superfluous.
Ridiger then proceeds to treat us with four long " demonstrations a priori,"
and to one elaborate "demonstration a posteriori ;" but as these are all
founded on the blunders now exposed, it would be idle to refute them in
detail.
Ridiger, it may Well surprise US, howbeit the professed champion of " the old
and correct doctrine," is virtually, perhaps unconsciously, a confessor of the
truth of "the new and false prejudice;" for I find him propounding four
several syllogistic forms, three of which are only valid through the universal
quantification of the predicate in affirmatives, and two (including the other
one) proceed on a correct, though partial, view, opposed to that of the logi-
cians, touching the conclusion of the Second Figure (L. II. c. iv). I shaU
insert the quantities, operative but not expressed.
In the First Figure — "At, aut ego nihil video, aut longe naturalior est hic
processus: — Quoddam Jluidum est {jjuoddani] leve; quoddam corpus est {^omne^
Jluidum; ergo quoddam corpus est quoddam leve ; quam si dicas, etc. (§ 34). —
Here the middle term is, and must be, afiirmatively distributed as predicate.
In the Second Figure. — " Verbi gratia: — Quoddam ens est [omne'} animal:
omnis homo est [quoddam} animal : ergo, omnis homo est [qv^ddam} ens. Haec
conc^usio verissima," etc. (§ 39.) In like manner the middle is here universally
quantified in an affirmative. C, i— — — : M, ■«■ : F-
The following, Ridiger (p. 330) gives, as " Two new moods, which cannot
be dispensed with." — " Quoddam animal est {omnis} homo : nullum brutum est
[ullus} homo : ergo, quoddam animal non est [ullum} brutum. Item : — Quod-
dam animal non est [uUus} homo ; omnis civis est [qtndam} homo ; ergo, quoddam
animal non est [ullus} civis." In the first of these, the middle, as predicate,
is affirmatively distribtrted ; and in both syDogisms, one conclusion, denied by
658
APPENDIX,
the logicians, is asserted by Ridiger, although the other, which involves a pred*
icate, particular and negative, is recognized by neither.
a) aODFRET PLOUCQUET.
Godfrey Ploucquet, a philosopher of some account, Professor of Logic and
^letaphysics in the University of Tubingen, by various writings, from the year
1759, endeavored to advance the science of reasoning; and his failure was
perhaps owing more to the inadequacy and limitation of his doctrine, than to
its positive error.' To jajLaQthing about his attempt to -reduce Logic to a
species of computation, in which his one-sided views came into confliction with
the one-sided views of Lambert, he undoubtedly commenced auspiciously, on
the principle of a quantified predicate. This, like a few preceding logicians,
he certainty saw aRbrdod a mean of simplifying the conversion of proposi-
tions;' but he did not see that it could accomplish much more, if properly
applied, in the theory of syllogism. On the contrary, in syllogistic, he profes-
sedly returns, on mature consideration, to the ordinary point of view, and
thinks himself successful in recalling the common doctrine of inference to
a single canon. That canon is this : — " The terms in the conclusion are to be
taken absolutely in the same extension which they hold in the antecedent." —
" In conclusione sint termini plane iidem, qui in praemissis, intuitu quantitatis."
(Methodus tarn demonslrandi directe omnes syllogismorum species, guam viiia
fomim deter/endi, ope unius regulce ; — Methodus calculandi in Logicis ; passim.
Both in 1763.) This rule, as applied to his logical calculus, he thus enounces:
" Arrange the terms in syllogistic order ; strike out the middle ; and the ex-
tremes then afford the conclusion." — " Deleatur in prasmissis medius ; id quod
restat indicat conclusionem." (Methodus calculandi, passim : Elementa PhUoso-
phioe Contemplatixice, Logica, § 122, 1778.) This rule is_simple eflQugh^-but,
unfortunately, it is both inadequate and false. Inadequate (and this was always
sufficiently apparent) ; for it does not enable us to ascertain (and these the
principal' q"'^gfi""'>s) Imw mapyT^xpis"^^' prwhat identity — of what quantity —
and of what quality, can be legitimately placed in the antecedent. But it is
not true (though this was never signalized) ; for its peculiar principle is falsi-
fied by eight of the thirty-six moods, to wit, in affirmatives, by ix., x., xi., xii.,
and in negatives, by ix. b, x. a, xi. b, xii. a.* In all these, the quantity of an
extreme in the conclusion is less than its quantity in the antecedent. We can
hardly, therefore, wonder that Ploucquet's logical speculations have been
neglected or contemned ; although their author be an independent and learned
thinker, and his works all well worthy of perusal. But, though dismissed by
Hegel and other German logicians, not for its falsity, with supreme contempt,
Ploucquet's canon has, however, found its admirers in England, where I har\'e
lately seen it promulgated as original.
1 An extract from liis Funriamtnta Philoso-
phi<r. S/iectdntifrr, 1T59, containing I'loucquet's
octrine touching tLo quantification of tbe
predicate, will be found in Mr. Baynes'
Esiay, p. 128.
St See Table of Moods, Appendix XI. — ^
APPENDIX.
(k) ULKICH.
669
Institutiones Logicce et Metaphysicce,% 171, 1785. — " Non tantum subjecto
sed et pradicato, ad subjectum relatio, sua constat quantitas, suumque igitur
signum quantitatis praefigere Ik-et. Sed haec praedicati quantitas ex veterum
praeceptis saepe justo minor invenitur. In loco de conversione distinctius de eo
exponetur." In that place, however, nothing of the kind appears." *
YI.
CANONS OF SYLLOGISM; GENERAL HISTORICAL NOTICES
AND CRITICISM.
A. — HISTORICAL NOTICES.
I. — Quotations fkom Various Logicians.
(Collected and Translated Autumn 1844. See p. 213. — Ed.)
(a) DAVID DERODON.
David Derodon (who died at Geneva in 1664, and had been previously
Professor of Philosophy at Die, Orange and Nismes) was a logician of no
httle fame among the French Huguenots; the study of his works was (if I
recollect aright) even formally recommended to the brethren of their com-
munion by one of the Gallican Synods. " Either the Devil or Doctor Dero-
don," was long a proverbial expression in France for the authorship of an
acute argument; and the " Sepulchre of the Mass" has been translated into the
vernacular of every Calvinist country. Derodon has left two systems of Logic ;
1 [That the Extension of Predicate is always
reduced to Extension of Subject, j. c, is
equivalent to it, see Purchot, Instil. Phil.,
Logica, i. pp. 123, 125. Tracy, Siemens rf' Idc-
ologif, t. iii. Disc. Prel., pp. 99, 100. Crousaz,
Logique, t. iii. p. 190. Derodon, Logica Resti-
tuta, P. ii. c. V. art. 4, p. 224. BoAhius,
Opera, p. 348 (see above, p. 551). Sergeant,
Method to Science, b. ii., less. i. p. 127. Beneke,
Lehrbuch der Logik, f 156, p. 100. Stattler,
Logica, § 196.
That the Predicate has quantity, and po-
tential designation of it as well as the Sub-
ject, see HolTbauer, Analytic der Urtheile und
Scldusse, ^ 31 el seq. Lambert, 2)ci/«5cApr Gelehrter
Briefwechsel, Brief vi. vol. i. p. S95. Platner,
Philosophische Aphorismen, i. § 546. Corvinus,
Listit. Phil. Rat., i 413. Conimbricenses, In
Arist. Dial.,'t. ii. pp. 158, 283. Scotus, In An.
Prior. L. i. qn. 4, f. 240; qu. 13, fT. 254^, 255»;
qu. 14, f 256b; qu. 23, f. 273».
For instances of Aristotle virtually using
distributed predicate, see An. Post., i. 6, i 1
Cf. Zabarella, ad loc. Opera Logica, p. 735
The same. In An. Post., I. 2. Opera, p. 827
and De Quarto Figura Syllog. Op., p. 123.
The adding mark of universality to predicate
is, Aristotle says, "useless and impossible'
(An. Prior., i. c. 27, § 9); yet see ii. c. 22, §} 1
8; c. 23, §§ 4, 5. On this question, see Bol
zano, Logik, § 131, p. 27, (and above, pp. 543
648,549.)
That the predesignation of the predicate by
aU collectively, in fact, reduces the universal
to a singular proposition, see Purchot, Instit.
Phil.,i. p. 124. Cf Logica Contracta Trajeetina.
P. ii. C.5. (1707. U
560 APPENDIX.
a larger (Logica Restztttta, 1659) and a smaller (Logica Contracta, 1664), both
published in 4to.^ I shall quote only from the former.
It is impossible to deny Derodon's subtlety, but his blunders unibrtunately
outweigh his originality. Leaving Conversion as he found it, after repeatins.
with approbation, the old rules, — that the predicate is not lo be overtly quan-
tified universally (p. 573), but to be taken, in affirmative propositions particu-
larly, as in negative propositions universally (p. 623) , we are surprised to find
him controverting, in detail, the special rules of syllogism. This polemic, r.s
might be expected, is signally unsuccessful; for it is frequently at variance wilii
all principle, and uniformly in contradiction of his own. It is, indeed, only
interesting as a manifestation, that the old logical doctrine was obscurely felt
by so original a thinker to be erroneous ; for the corrections attempted by
Derodon are, themselves, especially on the ground which he adopts, only so
many errors. He unhappily starts with a blunder; for he gives, as rectus, an
cxatBpIe of syllogism, in whicli the middle term is, even of neeessity, undis-
tributed; and he goes on (pp. 627, 628, 636, 637, 638, 639, 649) either lo
stumble in the same fashion, or to adduce reasonings, which can only be vindi-
cated as inferential by ftupplpng a universal quantity to the predicate in affir-
mative propositions, or by reducing it to particularity in negatives; both in the
teeth of Derodon's own laws. I have, however, recorrled, in my Table of Syl-
logisms, some of his examples, both the two forms which he has named, and
four others which he only enounces ; according, by liberal construction, what
was requisite to give them sense, and which, without doubt, the author would
liimself have recognized.
(b) KAPttr.
Rapin, Rdflexions sur la Loffiqu^, § 4, 1684.
" Before Aristotle there had a])pcared nothing on lo^c systematic and estab-
lished. His genius, so full of rea*on and intelligence, penetrated to the recesses
of the mind of man, and laid open all its secret workings in the accurate
analysis which he made of its operations. The depths of human thought had
not as yet been fathomed. Aristotle was the first who discovered the new way
of attaining to science, by the evidence of demonstration, and of proceeding
geometrically to demonstration, by the infallibility of the syllogism, the most
accomplishe<l work and mightiest effort of the human mind," etc.
Rapin errs in making Aristotle lay the rule of proportion along with the
Dictum de Omni as a principle 6f Syllogism.
(e) LEIBinTZ.
Leibnitz, De la conformile de la Foi avec la liaison, § 22. Op. t i., p. 81.
^" Hence the facihty of some writers is too great, in conceding that the doctrine
1 Derodon seems wholly unknown to the number in the same binding must h«ve been
titrman logicians, and, I need Itardly add, to imported at once, probably in consequence of
those of other countries. In Scotland, his the synodical recommendation,
works are not of the rarest; a considerable
APPENDIX. 561
of tbc Holy Trinity is repugnant with that great principle which enounces —
What are the same loith the same third, are the same with each other ; that is, if A
be the same with B, and C be the same with B, it is necessary that A and C
should also be the same with one another. For this principle flows immediately
from the principle of Contradiction, and is the ground and basis of ali Logic ;
if that fail, there is no longer any way of reasoning with certainty."
(d) REUSCH.
Reusch, Systema Logicum, 1 734.
§ 506. " That dictum of the Aristotehans de Omni et Nulla (503) evinces,
indeed, a legitimate consequence, but it only regulates one species of syllogisms,
at least immediately. By this reaso^^ therefore, looric.ians ^ftye been inducedJCL,
Y>rnvo tha ..r>n«pq.i<.»P<. nf |]^p ^\]\er specjes by means of the first, to which they
are reduced. But, that we may be able to supersede this labor, I have en-
deavored to give a broader basis to the Dictum de Omni et NuUo, or by what-
ever name that rule is called, to which, in the construction of syllogisms, the
order of thought is conformed.
§ 507. "For the whole business of ordinary reasoning is accomplished by
the substitution of ideas in place of the subject or predicate of the fundamental
proposition. This some call the equation of thoughts. Now, the fundamental ;
proposition may be either affirmative or negative, and in each the ideas of the
terms may be considered either agreeing or diverse, and according to this various :
relation there obtains a various substitution, which we shall clearly illustrate
before engaging with our doctrine of the Dictum de Omni et NuUo." £Having
done this at great length, he proceeds.]
§ 510. " From what has been now fn))j^ de/r-l/^fprl^ ^Ka Jhllfimliig Dietom-de'
Omni_et Nullo may be formed, which the definition itself of reasoning and
syllogism (§ 502) supports, and to which all syllogisms in every figure and
mood may be acconmiodated.
"//■ ttvo irieas (two terms) have, through a iudgmrnt rprnpnsitinn), receintA n
relation to each other, either affirmative or negative., in that case it is alloioable, in
place of either of these (that is, the subject or predicate of that judgment or
proposition), to substitute another idea (term), according to the rules given of
Equipollence or Reciprocation (§ 508, s. 9), of Subordination, of Coordination."'
(See Waldin, below, p. 565.)
(e) cuasms.
Crusius, Weg zur Gewissheit. Ed. i. 1747; Ed. ii. 1762.
§ 256. " The supreme law of all syllogism is. What we cannot otherwise think
than as true, is true, and what we absolutely cannot think at all, or cannot thirJc
but as false, is false." '
1 Kaut ( f/6er die Evidenz in inetaphysischen gard to the supreme rule of all certainty
Wissenrhnftrn, 17G3, Yerm. Schrifl ii. 43) has wbich tliis celebrated mau thought of placiii<;
liereon tlie following observation : — "In re- as the principle of all knowledge, and, couM'
71
662
APPENDIX.
§ 259. Of necessary judgments, of judgments which we cannot but think,
" which are not identical, and which constitute, in the last result, the positive or
the kernel in our knowledge ; to which we apply the principle of Contradiction,
and thereby enrich the understanding with a knowledge of real judgments," —
such judgments are principally the following : Every potoer or force is inherent
in a subject; All that arises (begins to be), arises in virtue of a sufficient
cause ; All whose non-existence cannot he thought, has its cause, and has at some
time arisen (begun to be) ; Every substance exists somewhere ; All that exists,
exists at some time ; Two material things cannot exkt at the same time, and in pre-
cisely the same place. There are also many other propositions, which treat of
ihe determinate qualification of things as present; for example — The same
point of a body cannot be at once red and green ; A man cannot be in two places
at once, and so forth. •
§ 261. " All the judgments previously alleged (§ 259) may be compre-
hended under these two general propositions, — What cannot in thought be sepa-
rated from each other, cannot be separated from each other in reality ; and, What
cannot in thought be connected into a notion, cannot in reality be connected ; to
wit, although no contradiction shows itself between the notions, but we are
only conscious of a physical necessity to think the thing so and so, clearly and
after a comparison of all the circumstances with each other. For we now
speak of propositions which are not identical with the Principle of Contradic-
tion, but of such as primarily afford the matters on which it may be applied.
Hence we see that the supreme principle of our knowledge given above
(§ 256) has two determinations ; inasmuch as the impossibility to think a
something arises either because a contradiction would ensue, or because we
are positively so compelled by the physical constitution of our thinking
faculties.
§ 262. " The highest principle of all syllogism thus resolves itself into the
three capital propositions :
1. Nothing can at once be and not be in the same point of view.
2. Things which cannot be thought without each other, without each other cannot
exist.
3. What cannot be thought as with and beside each other, cannot exist with and
beside each other, on the supposition even that between the notions there is no con-
tradiction.
" The second of these capital propositions I call the Principle of Insepara-
bles (principium inseparabilium) ; and the third the Prtncipfe of Inconjoinables
( principium inconjungibilium). They may be also termed the three Principles
of Reason."
Ch. VIII. Of the different species of .syllogisms, he says (§ 272), " Among
qnently, also of the metaphysical, — What I
cannot otherwise think than as true, is true, etc. ;
it is maiiilest that this proposition can never
be 0 principle of truth for any knowledge
whatover. For if it be agreed that no other
principle of truth is possible than inasmuch
as we are incapable of holding a thing not
for true, in this case it is acknowledged that
no other principle of truth is competent, and
that knowledge is indemonstrable. It is in-
deed true that there are many indemonstrable
knowledges, but the feeling of conviction in
regard to them is a confession, but not a
ground of proof, that they are true."' See
also Keid, Intelleetual Poteen, Essay iv. ch. 4.
APPENDIX. 563
the higher principles of syllogisms it is needful only to enumerate the Ptinciple
of Contradicfion, and the Principle of Sufficient Reason, which is subsumed
from the principle of Inseparables (§ 262). We shall state the laws of syllo-
gism in this order, — Consider those which flow, 1°, From the Principle of
Contradiction ; 2°, From the Principle of Sufficient Reason ; and, 3°, From
both together."
(f) FRANCIS nUTCHESON.
[Francisci Hutcheson.] Logicce Compendium. Glasguce, in cedibus academ-
icis, excudebant Robertus et Andreas Foulis, Academioe Typographi. 1 764.
Part III., Ch. ii., p. 58.
" The whole force of syllogism may be explicated from the following axioms.
" First Axiom. — Things which agree in the same third, agree among themselves.
" Second Axiom. — Things irhereof the one agrees, the other does not agree, in
one and the same third, these things do not agree among themselves.
" Third Axiom. — Things which agree in no third, do not agree among them-
selves.
" Fourth Axiom. — Things which disagree in no third, do not disagree among
themselves."
" Hence are deduced the general rules of syllogisms.
" Of these the three first regard the Quality [not alone] of Propositions.
" Rule 1 . — Jf one of the premises be negative, the conclusion will be negative
(by Ax. 2).
" Rule 2. — If both premises be affirmative, the conclusion will be affirmative
(by Ax. 1).
'• Rule 3. — If both premises be negative, nothing follows : because, of things
mutually agreeing and mutually disagreeing, both may be different from a third
thing (by Ax. 3, 4).
" Two Rules regard the Quantity of Terms.
" Rule 4. — Let the middle be once at least distributed, or taken universally ;
for the common term frequently contains two or more species mutually opposed,
of which it may be predicated according to various parts of its extension ; these
[specific] terms do not, therefore, truly agree in one third, unless one at least
of them agrees with the whole middle (by Ax. 3, 4).
" Rule 5. — No term ought to be taken more universally in the conclusion than
in the premises: because no consequence is valid from the particular to the
universal. [Because we should, in that case, transcend the agreement or diss^-
greement of the two terms in a third, on which, ex hypothesi, we found.]
" [In like manner there are two rules] concerning the Quantity of Proposi-
tions.
" Rule 6. — If one of the premises be particular, the conclusion will also be par-
ticular.
" For, Case I. — If the conclusion be affirmative, therefore both premises will
be affirmative (by Rule 1). But, in a particular proposition, there is no term
distributed ; the middle is, therefore, to be distributed in one or other of the
premises (by Rule 4). It will, therefore, be the subject of a universal affirma-
tive proposition ; but the other extreme is also taken particularly, when it i*
564
APPENDIX.
the predicate of an affirmative proposition, the conclusion will, therefore, be
particular (by Rule 5).
" Case II. — Let the conclusion be negative ; its predicate is, therefore,
distributed : hence, in the premises, the major and the middle terms are to be
distributed (by Rules 5 and 4).
" But when one of the premises is negative, the other is affirmative (by Rule
3). If one premise be particular, these two terms only can be distributed;
since one premise affirms, whilst the other is particular. The minor extreme,
the subject of the conclusion, is not, therefore, distributed in the premises; it
cannot, therefore (by Rule 5), be distributed in the conclusion.
" Rule 7. — From two particular premises nothing follows ; at least according
to the accustomed mode of speaking, where the predicate of a negative propo-
sition is understood to be distributed. For, 1°, If the conclusion affirm, both
premises will affirm, and, consequently, no term is distributed in the premises;
contrary to Rule 4. 2°, Let the conclusion be negative, its predicate is there-
fore distributed ; but in particular premises there is only distributed the predi-
cate of a negative proposition ; there is, therefore, necessarily a vice (either
against Rule 4 or Rule 6)."'
(a) SAVOyAROLA.
Savonarola, Compemlium Logices, L. iv. p. 115, ed. Venetiis, 1542. — " In
whatever syllogism any proj)osition can be concluded, there may also be con-
cluded every other proposition which follows out from it." On this he remarks :
" When any syllogism infers a conclusion flowing from its immediate conclu-
sion, it is not to be called one syllogism, but two. For that other conclusion does
not follow simply in virtue of the premises, but in virtue of them there first
follows the proper conclusion, and from this conclusion there follows, by another
syllogism, the conclusion consequent on it. Hence there are tacitly two syllo-
^sms ; otherwise the moods of syllogisms wbuld be almost infinite."
(h) BAUltGARTEHr.
Baumgarten, Acroasis Logica. Ed. Tollncr. Ed. I. 1765.
§ 297. " Every reasoning depends on this proposition : — A and B connected
A B
Some Frenchmen are [wme] learned ;
C B
Some EnnJidtmcn are not [any] Icnrneii ; Thax/hn,
lome Englithmen are not some Frenchmen."
1 "Rules 1 and 7 are thus contracted into
one : The conclusion follows the weaker part ;
that is, tlie negative or the particular. All
these Rules are included in the loUowing
verses:
Distribuat mtdium, nee qnartui terniinut addt,
Utraquc ncc prseinissa ncgans, ncc particiilaris.
Sicti'tur partem coiicliisio di'ttiiorem;
IZt uoa diatribuat niii cum praemina, n^jstre.
In an unusual mode of speaking, a certain (What arc within [ ] arc by me). [Written
negative conclusion may be effected with a Autumn, 1844. In the latest notation (,) i>
non-distributive predicate. As iu thia ex- substituted for (.),ihh1 (:) for (:.). SeeAppeu-
mmple^ dixXI -Ed.]
APPENDIX. 666
with a third C, are connected mlh each other : in affirmation immediately, in
negation mediately. This proposition is, therefore, the foundation and princi-
ple of all reasoning ; which, however, is subordinate to the principle of Con-
tradiction.
§ 324. " Every ordinary syllogism concluding according to the Dictum^ either
de Omni, or de Nulla. This Dictum is thus the foundation of all ordinary syllo-
gisms." (It had been previously announced, §§ 31D, 321.)
" AVhatever is truly affirmed of a notion universally, is also truly affirmed
of all that is contained under it Whatever is truly denied of a notion univer-
sally, is also truly denied of all that is contained under it."
(i) REIMARUS,
Reimarus, Vernunftlehre. 1766.
§ 176. " The fundamental rules of syllogism are, consequently, no other than
the rules of Agreement [Identity] and of Contradiction. For what the geometer
in regard to magnitudes takes as the rule of equality or inequality, that the
reasoner here adopts as the universal rule of all mediate insight : — If two things
be identical with a third, they are also in so far identical with each other. But if
the ovc he, and the other be not, identical with the third, then they are not mutuaUy
identical, but rather mutually repugnant."
§ 177. Here he notices that the Dictum de Omni et NuUo is not properly a
rule for all figures, but for the first alone.
(j) WALDUf.
Waldin, Novum Logiae Systcma. 17G6.
§ 335. " Since the syllogism rc(iuires essentially nothing but a distinct cogni-
tion of the sufiicient rea?on of some proposition, the most universal rule of all
syllogisms is, — The sufficient reason of a given proposition is to he distinctly
rognized.
§ 864. " The most general rule of all reasonings (§ 335) remains also the
rule of all reasonings as well in synthesis as in analysis. But in the synthesis of
the ordinary syllogism the middle term in the major proposition is referred to
the major term, in the minor proposition to the minor term. (§ 360.) Where-
fore, from this relation we must judge whether the middle term be or be not
the sufficient reason of the conclusion. Wherefore, the synthesis of the ordi-
nary syllogism is to be cognized from the relation of its ideas. This you may
tiius express :
" 1.) After the true proposition, the relation of whose extremes you distinctly
apprehend ;
" 2.) Add to its subject or predicate another idea different from bothf tokether
agreeing or disagreeing ;
" 3.) Inquire into Hie relation of the added idea, to the end that you may know
wliether the middle term in the given relation infer the conclusion ; and this . ••
known by the application of the rules of Reciprocation, Subordination, Coordina-
tion, and Opposition. If any one wish to call this the Dictum de Omni et Nullo
I have no objections."
5(66 APPENDIX.
"Observation. — ^This they call the Dictum de Omni et Nullo of the celebrated
Reasch. It stands true indeed, but is beset with difficulties, inasmuch as it is
rather a complexus of all rules than one ohly, which as yet is to be referred
to the class of pia desideria. Logicians have, indeed, taken pains to dis-
cover one supreme rule of all ordinary reasonings ; but no one has as yet
been so happy as to find it out" Then follows a criticism of the attempts
by the Port Royal and Syrbius.
(t) STATTLSS.
Stattler, Philosophia, P. I. Logica, 1 769.
§ 237. " In this comparison of two ideas with a third, six different cases may
in all occur : for, either,
I.) "One of the two ideas contains that same third, which again contains the
other; or,
2.) " Both of the two are contained in the third ; or,
S.) " Each of the two contains the third; or,
4.) " One of the two contains the third, the other being repugnant with it ;
or,
5.) "One of the two is contained in the third, with which the other is repugnant ;
or,
6.) " Both of the two are repugnant to the third.
•' The former three cases generate an affirmative conclusion, the latter three
a negative." In a note Stattler eliminates a seventh case, in which neither may
contain, and neither be repugnant to the third.
§ 244. General Law of all Reasonings. " In all reasonings, as often as a con-
sequent is, by legitimate form, inferred from an antecedent, so often is there
included in the antecedent what the consequent enounces ; either the congruity and
reciprocal containment, or the repugnance of A and C ; and if such be not
included in one or other of the antecedents, whatever is inferred in the consequent
is void of legitimate form."
(I) SAOTSK.
Sauter, Institutiones Logica:, 1798.
§ 1 23. " Foundations of Syllogism. — In ^verj' syllogism there are two notions
compared with a third, to the end that it may appear whether they are to be
conjoined or sejoined. There are, therefore, here, three possible cases. For
there agree with the assumed third, either both notions, or one, or neither. In
i-easoning, our mind, therefore, reposes on these axioms, as on fundament&l
principles.
1.) "Wliere txoo notions agree with the same third, they agree with one another.
2.) '• Where one is contained by the third, with which the other is repugnant,
they are mutually repugnant.
8.) " When neither notion agrees mth the third, there is between them neither
agreement nor repugnance."
APPENDIX. 567
(m) SUTEli.
Suter, Logica.
§ 61. " Quae eidem tertio conveniunt vel disconveniunt, etiam coaveniunt
vel discouveniunt inter se."
(n) SEGUT.
Seguy, Philosophia ad Usum Scholarum Accommodata, T. I. Logica. Paris,
1771.
P. 1 75, ed. 1 785. " Concerning the rule of recent philosophers."
Having recited the general rule of the Port Royal Logic, he thus comments
on it :
"1°, This is nothing else than the principle of reasoning; therefore, it is
improperly adduced as a neV discovery, or a rule strictly so called.
" 2°, It may be useful, to the rude and inexperienced, to recognize whether
a syllogism be legitimate or illicit.
" But the principal fault of this rule is, that it contains no certain method
whereby we may know when, and when not, one of the premises contains a
conclusion ; for the discovery of which we must frequently recur to the general
rules."!
P. 1 78. Seguy exposes Father Buflier's error in saying, " that, according to
Aristotle and the common rules of Logic, the middle term ought absolutely to
be the predicate in the first or major proposition ; " seeing that the middle term
is not the predicate in the first and third Figures. This must be a mistake ; for
I cannot find such a doctrine in Buffier, who, in this respect, in many places
teaches the correct.
(o) HOFFBACER.
Hoffbauer, Anfangsgriinde der Logik, 1794, 1810.
" § 317. Fundamental Principles.
" I. 1.) An attribute which belongs to all and every of the objects contained
under a notion, may also be aflii'med of these objects so contained. (Dictum
de Omni.)
" 2.) An attribute which belongs to none of the objects contained under a
notion, must also be denied of these objects so contained. (Dictum de NuUo.)
"II. When, of the objects X and Z, the one contains an attribute which the
other does not contain, and they are thus different from each other, then X is
not Z, and Z is not X.
"III. 1.) When objects which are contained under a notion a are also con-
tained under another notion b, then this last notion contains under it some at
least of the objects which are contained under the first.
" 2.) If certain objects which are not contained under a notion a are con-
1 Followed by Larroque, Elcmrns de Philo- Metqfisica, 1. 47, i. 348. E contra, Philosophia
tophie, p. 231; Galluppi, Lezioni di Logica e di Lugdunensis, i. 159. Troxler, Logik, ii. 41.
568 APPENDIX.
tained under &, tlien b contains under it some at least of the objects which are
not contained under a.
"IV. 1.) If objects which are contained under a notion a belong to those
which are contained under another notion b, then this second notion b contains
under it some at least of the objects which are contained under a.
" 2.) If all objects which are contained under a notion a belong to those
which are not contained under a certain other notion i, then this noUon b con-
tains under it no object which is contained under tJie notion a.
" 3.) If all the objects contained under a certain Aotion a are different from
certain other objects contained under b, then b contains under it at least some
objects which are not contained under a."
(p) KAST. 0
Kant, Lor/ik. 1800-6. II. Syllogisms.
" § 56. Syllogism in General. — A syllogism is the cognition that a certain
proposition is necessary, through the subsumption of its condition under a given
general rule.
"§ 57. General principle of all Syllogisms. — The general principle whereon
tlie validity of all inference, through the reason, rests, may be determiriately
enounced in the following formula :
" What stands under the condition of a rule, that stands also under the rule
itself.
"Ol)servatinn. — The syllogism premises a General Rule, and a Subsumption
under its Condition. Hereby we understand the conclusion a priori, not as
manifested in things individual, but as universally maintained, and as necessary
under a certain condition. And this, that all stands under the universal, and is
determinable in universal laws, is the Principle itself of Rationality or of Neces-
sity (principium rationalitatis seu necessitatis).
" § 58. Essetitial constituents of the Syllogism. — To every syllogism there
belong the three following parts :
" 1.) A general rule, styled the Major proposition (propositio major, Obersatz).
" 2.) The proposition which subsumes a cognition under the condition of the
general rule, called the Minor proposition (propositio minor, Untersatz) ; and,
finally,
" 3.) The proposition which affirms or denies the predicate in the rule of the
subsumed cognition, — the Concluding proposition, or Conclusion ( Conclusio,
Sehlussatz).
" The two first propositions, taken in connection with each other, are called
the Antecedents, or Premises ( Vordersdtze).
"Observation. — A rule is the assertion of a general condition. The relation
of the condition to the assertion, how, to wit, this stands under that, is the Ex-
ponent of the rule. The cognition, that the condition (somewhere or other)
takes place, is the Subsumption.
** TTic nexus of what is subsumed under the condition, with the assertion of
the rule, is the Conclusion."
Having shown the distribution of syllogisms into Categorical , Hypothetical,
and Diy'unctive, he proceeds to speak of the first class.
APPENDIX. 569
" § 63. Principle of Categorical Syllogisms. — The principle whereon the
possibility and validity of Categorical Syllogisms is this, — What pertains to the
attribute of a thing, that pertains to the thing itself; and what is repugnant to
the attribute of a thing, that is repugnant to the thing itself (Nola nolcc est
nota ret ipsius ; Repugnans notoe, repugnat rei ipsi).
*^ Observation. — From this principle, the so-called Dictum de Omni et Nullo
is easily deduced, and cannot, therefore, be regarded as the highest principle
either of the Syllogism in general, or of the Categorical Syllogism in particular.
Generic and Specijic Notions are in fact the general notes or attributes of all
the things which stand under these notions. Consequently the rule is here
valid — What pertains or is repugnant to the genus or species, that also pertains
or is repugnant to all the objects tohich are contained under that genus or species.
And this very rule it is which is called the Dictum de Omni et Nullo."
(q) CHRISTIAN WEISS.
Christian Weiss, Logifc, 1801.
" § 216. Principle for all Syllogisms. — The principle of every perfect Syllo-
gism consists in the relation of one of the notions contained in the conclusion to a
third notion (terminus medius), to ivhich the other notion of the conclusion belongs.
Now the relation which the first of these holds to the middle notion, the same must
hold to the second, just because the. second coincides with the middle notion to the
same extent as the first.
" Remark. — ^Relation to' means only any determinately thought relation
expressed in a judgment
" The older logicians adopt, some of them, the principle Nota noice est nota
rei ipsius, — quod repugnat notes, repugnat ipsi rei ; this, however, is only prop-
erly applicable to the first figure. The expression of others is preferable,
Qucecumque conveniunt (vel di-isentiunt) in uno tertio, eadem conveniunt (vel
dissentiunt) inter se. Others, in fine, among whom is Wolf, give the Dictum de
Omni et Nullo (cf. § 233) as the principle of syllogisms in general ; compare
Philosophical Aphorisms [of Platner], P. i. § 546. All inference takes place
according to a universal rule of reason, here only expressed in reference to
syllogism, to which, however, some have chosen to give a more mathematical
expression : — If ttoo notions be equal to a third, they are also equal to each
other.
[iVoto bene. — Weiss's mistake (§ 231) in supposing that Aristotle " desig-
nated the syllogistic moods with words, like his learned followers."]
"§231. Categorical Syllogisms, Figure 1. — The first figure concludes by
means of a subordination of the minor term in the conclusion under the subject
of another judgment.
" § 233. This takes place under the general principle :
" 1.) What pertains to all objects contained under a notion, that pertains also to
some and to each individual of their number among them.
" 2.) What belongs to none of the objects contained under a notion, that also
does not jwrtain to some or to any individual of their number among ihem.
*' These are the celebrated Dicta de Omni and de Nullo, — Qaidquid prce'
12,
570 APPENDIX.
dicatur de omni, idem etiam de aliquo, and, Quidquid prcedicatur de nuUo, id n9»
de aliquo prmdicatur"
(r) FRIES.
Fries, System der Logik.
" § 52. Hitherto we have maintained two views of the Syllo^sm in connec-
tion. The end in view of reasoning is this, — that cases should be subordinated
to general rules, and through them become determined. For example, the
general law of the mutual attraction of all heavenly bodies has its whole signi-
ficance, for my knowledge, in this, that there are given individual heavenly
bodies, as Sun and Earth, to which I apply it. To enounce these relations, it
is, in the first place, necessary that I have a general rule, as Major Proposition
(Obersatz) ; in the second, a Minor Proposition (Untersatz), which subordi-
nates cases to the rule ; and, finally, a Concluding Proposition, which determines
the cases through the rule. On the other hand, we see that every Conclusion
is an analytico-hypothetic judgment, and this always flows from the Dictum de
Omni et Nullo, inasmuch as the relation of subordination of particular under
universal notions, is the only relation of Reason and Consequent given in the
form of thought itself Now, if the conclusion, as syllogism, combines a plu-
rality of judgments in its premises, in this case the principle of the inference
must lie in a connection of the thoughts, — a connection which is determined
by the matter of these judgments. In the simplest case, when taking into ac-
count only a single syllogism, I thus would recognize in the premises the rela-
tion of subordination between two notions by reference to the same third
notion, and therethrough perceive in the conclusion the relation of these two
notions to each other. I know, for example, that all men are mortal, and that
Caius is a man. Consequently, through the relation of the notion of mortality ,
and of my imagination of Caius, to the notion man, the relation of Caius to
mortality is likewise determined : — Caius is mortal. The first of these views
is a mere postulate ; but in conformity to the second we are enabled imme-
diately to evolve the general form of syllogisms, and from this evolution does
it then become manifest that all possible syllogisms satisfy the postulate. We,
therefore, in the first instance, attach oui-selves to the second view. Through
this there is determined as follows :
" 1.) Here the determination of one notion is carried over to another, super-
ordinate or subordinate to itself. To every syllogism there belong three
notions, called its terms (termini). (We say notions (Begriff), because they
are, in general, such, and when individual reprt^sentations [or images] appear
as terms, in that case there is no inter-commutation possible.) A major term,
or superior notion (Oberbegriff), P, is given as the logical determination of a
middle term or notion (Mittelbegriff), M, and, through this, it is positively or
negatively stated as the determination of a minor term or notion .(Unlerbeg-
riff),S.
*' 2.) If, then, we regard the propositions in which these relations are
enounced, there is, firstly, in the conclusion (Schlussatz), the minor term, or
inferior notion, subordinated to the major term, or superior notion (S is P).
Further, in one of the premises, the middle must be connected with the major
term or notion (M is P). This is' called the major propositio/i (Obersatz). lu
APPENDIX. 571
the other, again, the minor is connected with the major term or notion (S is
M) ; this is called the minor proposition (Untersatz).
" The form of every syllogism is therefore —
Major Proposition, M is P.
Minor Proposition, S is M.
Conclusion, S i« P.
" In the example given above, man is the middle term ; mortality the major
term ; and Caius the minor term. The syllogism is —
Major Proposition, All men are mortal;
Minor Proposition, Cuius is a many-
Conclusion, Caius is mortal.
" The fundamental relation in all syllogisms is that of the middle term to
the major and minor terms ; in other words, that of the carrying over of a
logical determination from one notion to another, through certain given sub-
ordinations. For, howbeit the Dictum de Omni et NuUo, as a common princi-
ple of all syllogisms in the formula, — What holds good of the universal, holds
also good of the particulars subordinate thereto, and still more in that other, —
The attribute of the attribute is also the atiribute of the thing itself — is proxi-
mately only applicable to the categorical subordination of a representation [or
notion] under a notion; still, however, the law of mental connection is alto-
gether the same in syllogisms determined by the subordination of consequence
under a reason [Hypothetic Syllogisms], or of the complement of parts under
a logical whole [Disjunctive Syllogisms]. The displayed form is the form of
every possible syllogism. In fact, it also coincides with the first requirement
that, in the syllogism, a case should always be determined by a rule, inasmuch
as every syllogism proposes a universal premise, in order rigorously to infer
its conclusion. This will be more definitely shown when we treat of syllo-
gisms in detail. Only the declaration, that the rule is always the major proposi-
tion, is sometimes at variance with the declaration, that the major proposition
contains the relation of the middle term to the major term. We must, however,
in the first place, always follow the determination of the latter. For every
syllogism properly contains the three processes : — 1). The subordination of a
particular under a universal ; this is the function of the minor proposition, ^^^
the relation between the minor and major terms ; 2). Postulate of a logical
determination for one of these two ; this is the function of the major proposi-
tion, and the relation of the middle to the major term; 3). The carrying over
this determination to that other ; this is the function of the conclusion and the
relation of the minor to the major terms.
" § 53. The subordination of a particular to a universal must, therefore, in
every syllogism, be understood wholly in general. Here either a particular
may be determined through the superordinated universal, and such an in-
ference from universal to particular we shall call a syllogism in the first figure;
or there Is a universal known through its subordinated particular, and this
inference from the particular to the universal is called a syllogism in the second
Ithird'] figure. If, for example, the subordination is given me, — All gold is
572 APPENDIX.
metal; I can either transfer an attribute of metal, for instance fusibility, to the
gold, or enounce an attribute of gold, ductility, for instance, of some metal. In
the first case, I draw a conclusion in the first figure, from the universal to the
particular :
AU metal is fusible ;
All gold is metal;
AU gold is fusible.
" In the other case, I conclude in the second [third] figure from the par-
ticular to the general :
All gold is ductile ;
AU gold is metal;
Some metal is ductile.
Then, after distribution of the Syllogism into Categorical, Hj'pothetical, and
Divisive (Disjunctive), he proceeds with the first class.
($) KIESEWETTER.
BLiesewetter, Allgemeine Logik, 1801, 1824. I. Theil.
" § 228. — All pure Categorical Syllogisms, whose conclusion is an affirma-
tive judgment, rest on the following principle : — What pertains to the attribute
of an object, pertains to the object itself. All syllogisms, whose conclusion is a
negative judgment, are based upon the principle: — What is repugnant to the
attributes of an object, is repugnant to the object itself. Two principles which
can be easily deduced, — the first from the principle of Identity, the second
from the principle of Contradiction.
" § 229. — If we take into consideration that the major proposition of every
categorical syllogism must be a universal rule, — from this there flow the fol-
lowing rules :
" 1. Whatever is universally affirmed of a notion, that is also affirmed of
everything contained under it. The Dictum de Omni.
" 2. What is universally denied of a notion is denied also of everything con-
tained under it. The Dictum de Nullo.
" These rules are also thus expressed :
" What pertains to the genus or species, pertains also to whatever is con-
tained under them. What is repugnant to the genus or species, is repugnant
also to whatever is contained under them."
See also the Weitere Auseinandersetzung on the paragraphs.
(I) LARROQUE.
Larroque, Eltmeng de Philosophie, Paris, 18S0. Logique, ch. i., p. 202.
"The attribute of an affirmative proposition is taken sometimes particularly,
Kometimes universally. It is taken particularly when it has a greater extension
than the subject; universally, when it has not a greater extension, which oc-
curs in every proposition where the two terms are identical. The reason of
APPENDIX. 573
this difference is palpable. If the attribute be a term more general than the
subject, we affirm that the subject is a species or individual contained in the
extension of the attribute : — Man is mortal ; Paul is learned ; — that is, man is
one, and not the only, species contained in the extension of the term mortal;
Paul is an individual, and not every individual, contained in the extension of
the term learned. If, on the contrary, the attribute be not more general than
the subject, the attribute is the same thing with the subject, and, consequently,
we affirm that the subject is all that is contained in the extension of the at-
tribute:— A circle is a plane surface, which has all the points in [a line calledj
its circumference at an equal distance from a point called its centre, — that is,
« circle is all or every plane surface, etc.
" The attribute of a negative proposition is always taken universally. When
we deny an attribute of a subject, "we deny of this subject everything that has
the nature of that attribute, that is to say, all the species, as all the individuals,
contained in its extension : The soul is not extended; to wit the soul is not any
of the species, not any of the individuals contained in the extension of the term
extended."
Ch. ii., p. 230. " We have supposed, in the demonstration of these rules
[the general rules of the Categorical Syllogism], that the attribute of an affirm-
ative premise is always taken particularly. It would, therefore, seem that the
calculations on which this demonstration rests are erroneous, whensoever the
attribute is not a term more general than the subject, for we have seen that,
in these cases, the attribute can be taken universally. But it is to be observed,
that when the two terms of a proposition are identical, if the one or the other
may be taken nniversally, they cannot both be so taken at once ; and that, if it
be the attribute which is taken universally, it ought to be substituted for the
subject, which then affords a particular attribute. A triangle is a figure which
has three sides and three angles. We cannot say. All triangle is all figure,
which, etc. ; but we can say. All triangle is some figure, which, etc. ; or, All figure
which has three sides and three angles it some triangle. Now, in adopting either
of these last expressions of the proposition, the attribute is particular."
Ch. iL, p. 231. "We have seen that the Syllogism inferred from its prem-
ises a proposition to be proved ; now this conclusion cannot be inferred from,
unless it be contained in, the premises. From this incontestable observation
the author of the Port Royal Logic has endeavored to draw the following pre-
tended rule, by aid of which we may detect the vice of any fallacious reasoning
whatsoever : 7'hus sJwuld one of the premises contain the conclusion, and the
other show (hat it is so contained. A great many treatises on Logic call this
the single rule of the moderns. This pompous denomination seems to point at
some marvellous discovery, of which the ancients had no conception, — at
some consummative result of the efforts of the human intellect. It is true,
indeed, that a syllogism is invalid if the conclusion be not contained in the
premises ; but a fine discovery forsooth ! This all the world already knew, —
Aristotle among the rest ; but he justly noted that it is not always easy to see
whether the conclusion be contained in the premises, and it is to assure our-
selves of this that he laid down his rules. The pretended rule of the Port
)74
APPENDIX
Royal is, therefore, not one at all ; it enounces only an observation, true but
barren."
(uj GALLUP VI.
Galluppi, Lezioni di Logica e di Metafisica. 1832. Lez. xlvii., p. 353, ed.
1841.
" In a reasoning there must be an idea, common to the two premises ; and a
judgment which affirms the identity, either partial or perfect, of the other two
ideas."
In the same Lecture (p. 348) he shows that he is ignorant of the law
<luoted from the Philosophia Luffdunensis, being by the authors of the L' Art de
Penser.
(V) BUTFIER.
Buffier, Premiere Logique, about 1725. The following is from the Recapitu-
lation, § 109:
The Syllogism is defined, a tissue of three propositions, so constituted that
if the two former be true, it is impossible but that the third should be true
also. (§ 63.)
The first Proposition is called the Major: the second the Minor; the
third the Conclusion, which last is the essential end in view of the s>'ll(^sm.
(§ 65.)
Its art consists in causing a consciousness, that In the conclusion the idea of
the subject comprises the idea of the predicate ; and this is done by means of a
third idea, called the Middle Term (because it is intermediate between the sub-
ject and predicate), in such sort that it is comprised in the subject, and com-
prises the predicate. (§ 67.)
If the first thing comprise a second, in which a third is comprised, the first
comprises the third. If a fluid comprise chocolate, in which cocoa is comprised,
the fluid itself comprises cocoa. (§ 68.)
To reach distant conclusions, there is required a plurality of syllogisms.
(§ 71.)
Our rule of itself suffices for all syllogisms, even for the negative ; for every
negative syllogism is equivalent to an affirmative. (§ 77.)
Hypothetical syllogisms consist in the enouncement, by the major premise,
that a proposition is true in case there be found a certain condition ; and the
minor premise shows that this condition is actually found. (§ 70.)
Disjunctive syllogisms, to admit of an easy verification, ought to be rednced
to hypothetical. (§ 81.)
Although the single rule, which is proposed for all syllogisms, be subject to
certain changes of expression, it is nevertheless always the most easy ; in feet,
all logical laws necessarily suppose this condition. (§ 87.)
The employment of Grammar is essential for the practice of Logic. (§ 90.)
By means of such practice, which enables us to estimate accurately the value
of the terms in every proposition, we shall likewise obtain the rule for the dis-
covery of all sophisms, which consist only of the mere equivocation of words,
and of the ambiguity of propositions. (§ 92 et s«g.)
APPENDIX. 576
(w) VTCTORiy.
Victorin, Neue naturVichere Darstellung der Logik, Vienna, 1835.
II. Simple Categorical Syllogisms. § 94. The fundamental rule of all such
syllogisms :
" In what relation a concept stands to one of two reciprocally subordinate con-
cepts, in the same relation does it stand to the other."
§ 94. First Figure ; fundamental rule: — "As a notion determines the higher
notion, so does it det^nnine the lower of the same : " or, " In what relation a
notion stands to one notion, in the same relation it stands to the lower of the same."
§ 96. Second Figure ; fundamental rule : — " When two notions are oppo-
sitely determined by a third notion, they aire also themselves opposed;" or, "7/"
two notions stand to a third in opposed relations, they also themselves stand in a
relation of opposition."
§ 98. Third Figure ; fundamental rule : — "As a notion determines the one of
two l_to jV] subordinate notions, so does it determine the other;" or, "In what
relation a notion stands to the one of two \to tV] subordinate notions, in the same
relation stands it also to the other."
§ 100. Fourth Figure; fundamental rule: — "As a notion is determined by
the one of two subordinate notions [^tico notions in the relation to each other of
subordination'], so does it determine the other;" or, "In what relation one of two
subordinated notions [^notions reciprocally subordinate or superordinate] stands as
to a third, in the same relation stands it also to the other."
II. — Fundamental Laws of Syllogism. — References.
(See Galluppi, Lezioni di Logica e di Metafisica, Lez. xlvii., vol. i. p. 345
et seq. ; Troxler, Logik, i. p. 33 ; Bolzano, Wissenschaftslehre, Logik, vol. ii.
§ 263, p. 543.)
I. Logicians who confound the Nota notse and the Dictum de Omni, being
ignorant of their several significances ; making them —
a) Coordinate laws without distinction.
Jiigcr, Handb. d. Logik, § 68 (1839) ; Prochazka, Gesetzb.,f d. Denken, § 217
(1842) ; Calker, Denklehre, § 143 (1822). Troxler, Logik, ii. p. 40.
b) Derivative ; the Dictum de Omni, to wit, from the Nota notae. This
supreme or categorical.
Wenzel, Elem. Philos. Log., §§ 253, 256. Canonik, § 64. Kant, Diefalsche
Spitzf.,^3. Logik, ^63. Krug, Logik, § 70. Bachmann, io^r*, § 123. Jakob,
Logik, § 262, 4th ed. 1800 ; 1st ed. 1788.
II. Logicians who enounce the law of Identity (Proportion), in the same
third, by the mathematical expression Equality.
Reimarus, Vernunftlehre, § 176. Mayer, Vemunftschlusse, i. p. 290. Arriaga,
In. Sum., D. III. § 3, p. 23.
III. Logicians who make the Dictum de Omni the fundamental rule of syl-
logisms in general.
Aristot., An. Prior., L. i. c. 1, § 4. Wolf, Phil. Rat., § 353. Scheibler, Op.
P. iv. De Syll. c. ii. § 12. Jac. Thomasius, Erot. Log., c. 395. Buttner, Cur-
676 APPENDIX.
sus PhUos., Log., § 146. Conimbricenses, In Arist. Dial., An. Prior., L, i. c. 2,
p. 204.
IV. Logicians "who confound or make coordinate the law of Proportion or
Analogj', and the Dictum de Omni.
Wvttenbach, Pr(ec. Philos. Log., P. iii. c. 6, § 4. Whately, Logic, Intr., eh.
II. p. iii., § 2. Leechman, Logic, P. III. ch. 2. Keckermann, Sj/stema Logicce
Minus, L. iii. c. 2. Syst. Log. Majus., L. iii. c. 5.
V. Logicians who make the Law of Identity the one supreme.
Suter, Logica, § 61, calls this the principle of Identity and Contradiction.
Aldrich, Comp., L. i. c. 3, § 3, p. 2. Hutcheson, Log. Comp., P. iii. c. 2.
Arriaga, Cur. Phil., In. Sum., D. iii. §§ 16-22, pp. 23, 24. Larroque, Logique,
p. 224. Mayer, Vemunftschusse, i. p. 293. Troxler, Logik, ii. pp. 33, 40.
Reimarus, Vemunftlehre, § 176. Mendoza, Disp. Log. et Met., I. p. 470.
Derodou, Log. Rest., De Log., pp. 639, 644. Darjes,ria., etc., § 271, p. 97.
Smiglecius, Logica, D. xiii. p. 517, qu. etc. Fran. Bonae Spei, Com. Prim, in
Log. Arist., D. vii. d. 2, p. 25. Cursus Complut., De Arg., L. iii. c. 4, p. 57.
Alstedius, Enc. Logica, § ii. c. 10, p. 435. Havichonet, Inst. Log., § 324.
Poncius, Cursus Philos. In An. Prior., D. xx. qu. 5, p. 282.
VI. Logicians who restrict the Dictum de Omni to the First Figure (im-
mediately).
Aldrich, Comp. 1. 1, c. 3, § 7. Noldius, Log. Rec, c. xii. p. 290. Grosser,
Pknrus Intellectus, § iii. p. 1, memb. iii. p. 13 7.
VII. Logicians who make the Dicta de Omni et Nullo the supreme canons
for Universal Syllogisms ; the law of Proportion for Singular Syllogisms.
Burgersdicius, Inst. Log., L. ii. c. 8, p. 171. Melancthon, EroL Dial., De
Syll. Expos., L. iii. p. 172, ed. 1586. Fonseca, Instil. Dial, L. vi. cc. 21, 24,
pp. 363, 373.
VIII. What name given by what logicians to the Law of Proportion, etc.
Law of Proportion, or of Analogy, Keckermann, Syst. Log. L. iii. c. 5, Op.,
p. 746. Alstedius, Encycl., p. 435, -rh i.ya\oyias. Dictum de Omni et Nullo
Majus, Noldius, Log., p. 288. Of Identity, Zedler's Lex. Pr. convenienticB.
Darjes, Via ad Verit, § 270, p. 96. Law of Proportional Identity and Non-
Identity, Self.
IX. Ix)gicians erroneously supposing Aristotle to employ, besides the Dictum
de Omni, the rule of Proportion as a fundamental law of syllogism.
Rapin, Reflexions sur la Logique, § 4.
X. Terms under which the law of Proportion has been enounced.
Agree with. Coincide with. The same with. Cohere (Syrbius). Coexist
(bad). Cdidentical with. Equal to (No. ii.). In combination with, Darjes, Via
ad Ver., p. 97 (includes negative). Convertible.
III. — Enunciations or thk HiOBEa Laws of Stllogism.
Law of Proportion.
Aristotle, Elench, c. vi. § 8. " Things the same with one and the same, are
the same with one another." Compare Topica, L. vii. c. 1, § 6. Thus Scotus,
In An. Prior., L. i. qu. 9, f. 248.
APPENDIX. 577
Some say, " Uni tertio indivisihili" — some others, " Uni tertio indivisibiii,
indivisiblliter sumpto." Others, in fine, say, " Uni tertio, adequate sumpto."
See Irenaeus, Integ. Philos. Log., §§ 3, 5. Some exj>ress it, " Things that are
equal to the same tliird are equal to each other." See Irenaeus, ih. So Reinv
arus, Mayer.
Some express it, " Quaecunque conveniunt (vel dissentiunt) in uno tertio,
eadem conveniunt (vel dissentiunt) inter se."
" Quffi duo conveniunt cum uno quodam tertio, eatenus conveniunt inter se;
quando auteni duorum unum convenit cum tertio, et alterum huic repugnat,
repugnant quoque eatenus sibi invicem." Wynpersse, Inst. Logicce, § 272, Lug.
Bat. 3d ed. 1806.
Noldius (Logica, p. 288) calls these the Dicta de Omni et de Nullo. The
former is, " Quaecunque affirmantur in aliquo tertio (singulari identice, univer-
sali et identice et complete distributive), affirmantur inter se." The latter,
" Quorum unum [totaliter] affirmatur in aliquo tertio, alterum negatur, ea inter
86 negantur."
Noldius. — "Whatever is affirmed essentially of a subject, is affirmed of all
that is inferior or reciprocal to that subject. Whatever is denied of a subject,
is denied of all inferior or reciprocal." (See Noldius against the universal
application of these Dicta, Log. Rec, p. 290.)
Reusch (Syst. Logicum, ed. i. 1734, § 503) makes the Dicta de Omni et
NuUo the rule of ordinary syllogisms, and thus enunciates them : " Si quid
praedicatur de omni, illud etiam praedicatur de aliquo : et, Si quid predicatur
de nuUo, illud etiam non praedicatur de aliquo. Sensus prioris est, Quidquid
de genere , vel specie omni prsedicari potest, illud etiam prsedicatur de quovis .
sub illo genere, vel sub ilia specie, contento ; Item, — Cuicunque competit
definitio, illi quoque competit definitum." (And so vice versa of the other.)
Syrbius gives these two rules :
1) " If certain ideas cohere with a one-third, they also cohere in the same
manner with each other."
2) " Ideas which do not cohere with the same one-third, these do not cohere
with each other." (Given in the original by Waldin, Sysiema, p. 162. See
also Acta Eruditorum, 1718, p. 333.) Syrbius thinks that the law of Propor-
tion, unless limited, is false.
Darjes, Via ad Veritatem (1755), § 270, p. 96, 2d ed. 1764. "Two [things or
notions] in combination with the same third, may be combined together in the
same respect (ea ratione) wherein they stood in combination with that third."
(See further; shows that other rules are derived from this.)
Dictum de Omni, etc.
Aristotle, Anal. Pr., L. i. c. i. § 11.
" To be predicated, de Omni, universally, is when we can find nothing under
the subject of which the other [that Is, the predicate] may not be said ; and to.
be predicated de Nullo, In like manner."
Jac. Thomasius, Erotemata Logica., 1670.
" 40. What do you call the foundation of syllogism ? — The Dictum de
Omni et Nullo.
"41. What is the Dictum de Omni? — When nothing can be subsumed.
73
§78 APPENDIX.
under the subject of the major proposition of which its predicate may not be
affirmed.
" 42. What is the Dictum de Nullo ? — When nothing can be subsumed
under the subject of the major proposition of which its predicate is not
denied."
Thomasius notices that the first rule applies only to the aflirmative moods of
the first figure, Barbara and Darii ; the second only to the negative moods of
the same figure, Celarent and Ferio.
IV. — Objections to the Dictom de Omni et Nullo.
I. As a principle of syllogism in general.
n. As a principle of the First Figure, as enounced by Aristotle.
1°, Only applies to syllogisms in extension.
2°, Does not apply to individual syllogisms ; as, Peter is running ; hut $ome
man is Peter; there/ore, some man is running.
(Arriaga, In. Surnm., p. 24.)
3°, Does not apply to coextensive reasonings ; as. All trilateral is (all) tri-
angular ; but all triangular has three angles equal to two right angles ; ergo, etc.
Arriaga, t6.
Dictum de Omni et Niillo does not apply,
1°, To the other Figures than the First.
2°, Not to all the moods of First Figure, for in many of these the higher
class is subjected to the lower.
3°, The form of the First Figure does not depend upon the principle of the
Dictum de Omni et Nullo. This imperfect ; not upon the thorough-going prin-
ciple, that in this figure one notion is compared to a second, and this second
with a third.
V. — General Laws of Stllooism in Verse.
(1) Partibus ex puris sequitur nil (2) sive negatis.
(3) Si qua prasit partis, sequitur conclusio partis.
(4) Si qua negata praeit, conclusio sitque negata.
(5) Lex generalis erit, medium concludere nescit.'
(6) Univocusque ; (7) triplex; (8) ac idem terminus esto.*
'(1) DIstribuas medium ; (2) nee quartus terminus adsit
(3) Utraque nee praemissa negans ; (4) nee particularis.
(5) Sectetur partem conclusio deteriorem ;
(6) Et non distribuat nisi cum prsemissa, (7) negetve.*
1 Petrus Hispanns, Summula. [Tr. iv. c. 8, 2 Campanella, DiaUet., p. 384.
f 46 b. — Ed.] 3 Hutcbeson, Log. Comp. [P. iii. c. 8, p. 58.—
Ed.]
APPENDIX.
679
Terminus csto triplex : medius, majorque, minorque :
Latins hunc quam prjemissse, conclusio non vult,
Nequaquam medium capiat conclusio oportet.
Aut semel aut itcrum medium generaliter esto.
Nil sequitur geminis ex particularibus unquam.
Utraque si praemissa neget, nihil inde sequetur.
Ambae afRrmantes nequeunt generare negantem.
Est parti similis conclusio deteriori. ^
Pejorem sequitur semper conclusio partem. )
Terminus est geminus, mediumque accedit utrique.
Prsemissis dicat ne finis plura, caveto.
Aut semel, aut iterum medium genus omne capessat ;
Officiique tenax rationem daudere nolit.
Terminus est triplex. (2) Medium conclusio vitet.
Hoc ex prseniissis altera distribuaL
Si praemissa simul fuit utraque particularis,
Aut iitrin(jue negans, nulla sequela veniL
Particulare praeit V sequitur conclusio partis.
Ponitur ante negans ? Clausula talis erit.
Quod non prascessit, conclusio nulla requirit.*
Tum re, tum sensu, triplex modo terminus esto.
( Argumentari non est ex particulari.
I Neque negatlvis recte concludere si vis.
j Nunquam complecti medium conclusio debet.
I Quantum praemissae, referat conclusio solum.
( Ex falsis falsum verumque aliquando sequetur;
( Ex veris possunt nil nisi vera sequi.'
VI. — Special Laws of Syllogism in Veesb.
1 . Fig. Sit minor affirmans, nee major particularis.
2. Fig. Una negans esto, major vero generalis,
3. Fig. Sit minor affirmans, conclusio particularis.
4. Fig. a) Major ubi affirmat, generalem sume minorem.
b) Si minor affirmat, conclusio sit speclalis.
c) Quando negans modus est, major generalis habetur.*
B.— CRITICISM.
L — Chiticism of the Special Laws op Syllogism.
The Special Laws of Syllogism, that is, the rules which govern the several
Figures of Categorical Reasonings, all emerge on the suspension of the logical
1 Purchot, with variations of Seguy, Ph.
Lugd., Galluppi. [Purchot, Inst. Phil., vol.
i., Logicn, P. iii. c. 3, p: 171. — Ed.]
a Isendoorn, Logica, L. iii. c. 8, p. 427, 8°,
(1652). Chauvin and Walch, Lex. v. Syttog.
3 Crakanthorpe, Logica, L. iii. c. 15, p. 210.
4 Ubaghs, LogicBR Elementa, § 225. Sancru-
cius, Dialeetiea ad Mentem Doet. SubtUis, L. i.
c. 3, p. 103. Lend. 1673.
S§0 APPENDIX.
postulate, — To be able to state in language what is operative in thought
They all emerge on the refusal or neglect to give to the predicate that quantity
in overt expression which it possesses in the internal operations of mind. The
logicians assert, 1°, That in affirmative propositions the predicate must be
always presumed particular or indefinite, though in this or that proposition it
be known and thought as universal or definite ; and, 2°, That in negative
propositions this same predicate must be always presumed absolutely (i. e.,
universally or definitely) excluded from the sphere of the subject, even though
in this or that proposition it be known and thought as partially (i. e., partic-
ularly or indefinitely) included therein. The moment, however, that the s^d
postulate of Logic is obeyed, and we are allowed to quantify the predicate in
language, as the predicate is quantified in thought, the special rules of syllo-
gism disappear, the figures are all equalized and reduced to unessential modi-
fications ; and while their moods are multiplied, the doctrine of syllogism itself
is carried up to the simplicity of one short canon. Having already, shown that
the general laws of syllogism are all comprised and expressed in this single
canon,^ it now only remains to point out how, on the exclusive doctrine of the
logicians, the special rules became necessary, and how, on the unexclnsive doc-
trine which is now propounded, they became at once superfluous and even
erroneous. It is perhaps needless to observe, that the following rules have
reference only to the whole of Extension.
The double rule of the First Figure, that is, the figure in which the middle
term is subject in the sumption, and predicate in the subsumption, is, — SU
minor affirmans ; nee major particularis. Here, in the first place, it is prescribed
that the minor premise must be aflfirmative. The reason is manifest ; because,
if the minor premise were negative, the major premise behooved to be affirma-
tive. But in this figure, the predicate of the conclusion is the predicate of the
major premise ; but if affirmative, the predicate of that premise, on the doctrine
of the logicians, is presumed particular, and as the conclusion following the
minor premise is necessarily negative, a negative proposition thus, contrary to
logical law, has a particular predicate. But if we allow a negative proposition
to have in language, as it may have in thought, a particular or indefinite predi-
cate, the rule is superseded.
The second rule, or second part of the rule, of this First Figure, is, that the
major premise should be universal. The reason of this is equally apparent
For we have seen that, by the previous rule, the minor premise could not be
negative, in which case certainly, had it been allowable, the middle term would,
as predicate, have been distributed. But whilst it behooved that the middle
term should be once at least distributed (or taken universally), and, as being
the subject of the major premise, it could only be distributed in a universal
.proposition, the rule, on the hypothesis of the logicians, was compulsory. But
as we have seen that the former rule is, on our broader ground, inept, and that
the middle term may be universally quantified, as the predicate either of an
affirmative or negative subsumption, it is equally manifest that this rule is, in
like manner, redundant, and even false.
In the Second Figure, that is, the figure in which the middle term is predica^
1 See pp. 636and A88. — Bd.
APPENDIX. 581
both in sumption and subsumption, the special rule is, — Una negans esio ;
major vero generalis.
In regard to the first rule^ or first half of the rule, — That one or other of
the premises should be negative, — the reason is manifest. For, on the doc-
trine of the logicians, the predicate of an afiirmative proposition is always
presumed to be particular ; consequently, in this figure the middle term can,
on their doctrine, only be distributed (as distributed a£ least once it must be)
in a, negative judgment. But, on our doctrine, on which the predicate is quan-
tified In language as in thought, this rule Is abolished.^
The second rule, or second moiety of the rule, — That the sumption should
be always univei"sal, — the reason of this is equally clear. For the logicians, not
considering that both extremes wei'e in equlllbrio in the same whole of exten-
sion, and, consequently, that neither could claim [in either quantity] the place
of major or minor term, and thereby constitute a true major or a true minor
premise ; -^ the logicians, I say, arbitrarily drew one instead of two direct con-
clusions, and gave the name of major term to that extreme which formed the
predicate in that one conclusion, and the name of major premise to that ante-
cedent proposition which they chose to enounce first. On their doctrine,
therefore, the conclusion and one of the premises being always negative, it
behooved the sumption to be always general, otherwise, contrary to their doc-
trine, a negative proposition might have a particular predicate. On our
doctrine, however, this difficulty does not exist, and the rule is, consequently,
superseded.
In the Third Figure, that is, the figure in which the middle term is subject
of both the extremes, the special rule Is, — Sil minor riffirwans ; conclusio par-
tictdaris.
Here (he first half of the rule, — That the minor must not be negative, —
is manifestly determined by the common doctrine. For (mnjor and minor
terms, major and minor propositions, being in this figure equally arbitrary as in
the second) here the sumption behooving lo be affirmative, its predicate, con-
stituting the major term or predicate of the conclusion, behooved to be partic-
ular also. I>ut (he conclusion following the minor premise would necessarily
be negative ; and It would have — what a negative proposition is not allowed
on the common doctrine — an undistributed predicate.
The second half of the rule, — That the conclusion must be particular,—
is detennined by the doctrine of the logicians, that the particular antecedent,
which they choose to call the minor term, should be affirmative. For, in this
case, the middle term being the subject of both premises, the predicate of the
aubsumption is the minor extreme ; and that, on their doctrine, not being dis-
tributed in an affirmative proposition, it consequently forms the undistributed
1 [For examples from Aristotle of affirma- ositions in Second Figure, and does not give
live coiiclus)oii*i.iu the Second Figure, see De the reason why the inference is good or bad
Olio, L. ii. c. 4, i 4, text 23, ibi Averroes. in such syllogism. Cf. Ammonius and Philr-
Pi'iys. L. ii. c. 2, § 12, text 23, ibi Averroes; c. ponus ad. loc. An. Prior, L. ii. c. 22, §} 7, >*.
4. i 8, text 38, ibi Averroes. Jb.c. 7, § 1, text An. Post , L. i. c. 6, § 1, et ibi, Themistiu:,
42, ibi Averroes. An. Post, L. i. c. 12, § 12, Pacius, Zabarella. Cf. also Zabarella, Df
text 92, ibi Averroes et Pacius. Argues him- Quarta Fig. Syll., c. x.]
fcelf, like Cseneus, from two affirmative prop-
582 APPENDIX.
subject of the conclusion. The conclusion, therefore, having a particular aulx
ject, is, on the common doctrine, a particular proposition. But as, on our
doctrine, the predicate of an affirmative proposition may have a universal
quantification, the reason fails.
n. — Laws of Second Figure — Additional.^
By designating the quantity of the predicate, we can have the middle term
(which in this figure is always a predicate) distributed in an affirmative propo-
ntiou. Thus :
AUPisaUM;
AU S x$ some M ;
Therefore, all S is some P.
AU the things that are orgnnized are all the tilings that are endowed with Ufe ;
Btft all plants are some things endowed with life;
Therefore, aU plants are some things organized.
This first rule (see above, p. 291) must, therefore, be thus amplified: — The
middle term must be of definite quantity, in one premise at least ; that is, it
must either, 1"*, Be a singular, — individual, — concept, and, therefore, identi-
cal in both premises ; or, 2°, A universal notion presumptively distributed by
negation in a single preuiise ; or, 3"*, A univei"sal notion expressly distributed
by designation in one or both premises.
But the second rule, which has come down from Aristotle, and is adopted
into every system of Logic, with only one exception, an ancient scholiast, is
altogether erroneous. For, 1°, There is properly no sumption and subsump-
tion in this figure ; for the premises contain quantities which do not stand to
each other in any reciprocal relation of greater or less. Each premise may,
therefore, stand first. The rule ought to be, " One premise must be definite ; "
but such a rule would be idle ; for what is here given as a special canon of this
figure, was already given as one of the laws of syllogism in general. 2°, The
error in the principle is supported by an error in the illustration. In both the
syllogisms given,* the conclusion drawn is not that which the premises warrant-
Take the first or affirmative example. The conclusion here ought to liavo
been. No S is some P, or. Some P is »)o S ; for tliere are always two eijuivalent
conclusions in this figure. In the concrete example, the legitimate conclusions,
as necessitated by the premises, are, — No horse is some animal, and. Some
animal is no horse. This is shown by my mode of explicating the quantity of
the predicate, — combined with my symbolical notation. In like manner, in
the second or negative syllogism, the conclusion ought to have been either
of the two following: In the abstract formula, — All S are not some P, or.
Some P are not all H; — in the concrete example, AU topazes are not some min-
I What follows to paj;e 583 was on early The iuterpolation apjiears in students' notes
written interpolation by the author in Lr.c- of the Lectures of session 1841-12, and was
tures (p. 291), being an application of the prin- probably given still earlier.— Ed.
•iple of a quantified predicate to syllogism. ii See p. 292. — Rd.
APPENDIX. 583
erah, i. c, No topazes are some minerals, or, Some minerals are not all topazes,
i. e., Some minerals are no topazes.
The moods Cesare and Camestres may be viewed as really one, for they
are only the same syllogism, with premises placed first or second, as is always
allowable in this [Figure], and one of the two conclusions, which are always
legitimately consequential, assigned to each.
A syllogism in the mood Festiuo admits of either premise being placed first ;
it ought, therefore, to have had another mood for its pendant, with the affirma-
tive premise first, the negative premise second, if we are to distinguish moods
in this figure by the accidental arrangement of the premises. But this was
prohibited by the second Law of this Figure, — that the Sumption must always
be universal. Let us try this rule in the formula of Festino now stated, revers-
ing the premises.
Some S are M (i, e., some M);
JVoPtsM;
INoF is some S. 1
( Some S are no P. )
Some actions are praiseworthy ,•
No vice is praiseiDorihy ;
( No vice is some action.
I Some action is no nee.
From what I have now said, it will be seen that the Dictum de Omni et de
Nullo cannot afford the principle of the Second Figure.
The same errors of the logicians, on which I have already commented, in
supposing that the sumption or major premise in this figure must always be
universal, — an error founded on another error, that there is (properly speak-
ing) either sumption or subsumption in this figure at all, — this en or, I say,
has prevented them recognizing a mood corresponding to Baroco, the firs*
premise being a particular negative, the second a universal affirmative, i. «.,
Baroco with its premises reversed. That this is competent is seen from the
example of Baroco now given. Reversing it we have :
\^Some a are not B ; Some animals are not (any) oviparous ;
All a are B. All birds are (some) oviparous.
No a IS some d ; No bird is some animal;
Some a are no a.] Some animal is no bird.
m. — Author's Supreme Canoxs of Categorical Syllogisms.
[The supreme Canon or Canons of the Categorical Syllogism, finally adopted
by Sir W. Hamilton, are as follows :]
L " For the Unfigured Syllogism, or that in which the terms compared do
not stand to each other in the reciprocal relation of subject and predicate,
being, in the same proposition, either both si>bjects or (possibly) both predicates.
684 APPENDIX.
— the canon is : — In so far as ttco notions (notions proper, or individuals)
either both agree, or one agreeing, the other does not, with a common third nation ;
m so far, these notions do or do not agree tcitk each other.
11. " For the Figured Syllogism, in which the terms compared are severally
subject and predicate, consequently, in reference to each other, containing and
contained in the counter wholes of Intension and Extension, — the canon is :
— What worse relation of subject and predicate subsists between either of two
terms and a common third term, with which one, at least, is positively related ; that
relation subsvits between the two terms themselms.
"■ Each Figure has its own Canon.
f* First Figure : — What worse relation of determining (predicate) and of
determined (subject) is held by either of two notums to a third, with which one at
least is j^ositirely related ; that relation do they immediately (directly) hold to
each other, and indirectly (mediately) its converse.
" Second Figure : — What worse relation of determined (subject) is held by
either of ttco notions to a third, with which one at least is positively related ; that
relation do they hold indifferently to each other.
" Third Figure : — What icorse relation of determining (predicate) is held by
either of two notions to a third, with which one at least is positively related ; that
relation do they hold indifferently to each other." *
IV. — Ultra-Total Qdantification op Middle Term.
(a) LAMBERTS DOCTRINE.
Lambert, Neues Organon.
Dianoiologie, § 193. " If it be indetermined how far A does, or does not,
coincide with B, but, on the other hand, we know that A and B, severally,
make up more than half* the individuals under C, in that case it is manifest
that a [linear] notation is possible, and that of the two following kinds :
C c.
B- b,
A.
" For since B and A are each greater than the half of C, A is consequently
greater than C less by B ; and in this case, it is of necessity that some A are
B, and some B are A.* We may accordingly so delineate :
.B b.
seeing that it is indifferent whether we commence with A or with B. I may
add, that the case which we have here considered does not frequently occur,
inasmuch as the couiparative extension of our several notions is a relation
1 Dhcussiotis, pp. 654, 665. — Ed. I have elsewhere had occasion to show. See
Sit is enough if either A or B exceed the below, p. 688.
b*]f ; the other need be only half. This, 3 In the original, for A tbere is, by a tjrpo-
wbich Lambert liere and hereafter overlooks, graphical erratum, C. See Ph. } 206.
APPENDIX. 685
which remains wholly unknown.^ I, consequently, adduce this only as an exam-
ple, that a legitimate employment may certainly be made of these relations."
Phanomenologie, § v. Of the probable —
" § 188. In so far as such propositions are particular, they may, like all other
particular propositions, be syllogistically employed ; but no farther, unless we
look to their degree of particularity, or other proximate determination, some
examples of which we have adduced in the Dianoiologie (§ 235 et seq.). Thus
the degree of particularity may render a syllogism valid, which, without this,
would be incompetent. For example :
Three-fourths of A are B;
Ttco- thirds of A are C ;
Therefore, some C are B.
The inference here follows, because three-fourths added to two-thirds are
greater than unity ; and, consequently, there must be, at least, five-twelfths of
A which are at once B and C.
" § 204. In the Third Figure we have the middle term, subject in both
premises, and the conclusion, particular. If, now, the subjects of the two
premises be furnished with fractions [?'. e., the middle term on both sides], both
premises remain, indeed, particular, and the conclusion, consequently, indeter-
mined. But, inasmuch as, in both premises, the degree of particularity is
determined, there are cases where the conclusion may be drawn not only with
probability, but with certainty. Such a case we have already adduced (§ 188.)
For, if both premises be affirmative, and the sum of th^ fractions with which
their subjects are furnished greater than unity, in that case a conclusion may
be drawn. In this sort we infer with certainty :
Threefourths of A are B ;
Two-thirds of A are C ;
Therefore, some C are B.
" § 205. If, however, the sum of the two fractions be less than unity, as -^
One fourth of A are B ;
One-third of A are C,
1 In reference to this statement, see above, tive amount. For Logic and Philosophy
Dion, i 179, and below, Ph. § 157, where it is tend always to an unexclusive generality ;
repeated and confirmed. Lambert might and a general conclusion is invalidated
have added that, as we rarely can employ equally by a single adverse instance as by a
this relation of the comj>arative extension of thousand. It is only in the concrete or real
our notions it is still more rarely of any im- whole, — the whole quantitative or integrate,
port that we should. For in the two abstract, an^, whether continuous or discrete, the
or notional, wholes, — the two wholes correl- whole in which mathematics are exclusively
ative and counter to each other, with which conversant, but Logic and Philosophy little
Lo^ic is always conversant (the Universal and interested, — that this relation is of any avail
Formal ), — if the extension be not complete, or significance,
it is of no consequence to note its compara-
74
586 APPENDIX.
in that case there is no certainty in any affirmative conclusion [indeed in any
conclusion at all]. But if we state the premises thus determinately, —
Three-fourths of A are not B;
Tioo-thirds of A are not C ;
in that case, a negatiye conclusion may be drawn. For, from the propositions,
Three-fourths of A are not B ;
One-third of A are C;
there follows — Some C are not B. And this, again, because the sum of the
two fractions (three-fourths added to one-third) is greater than unity." And
so on. See the remainder of this section and those following, till § 211.
(t) AOTHOIPS DOCTRINE.
Aristotle, followed by the logicians, did not introduce into his doctrine of
syllogism any quantification between the absolutely universal and the merely
particular predesignations, for valid reasons. — 1°, Such quantifications were
of no value or application in the one whole (the universal potential, logical),
or, as I would amplify it, in the two correlative and counter wholes (the logical
and the formal, actual, metaphysical), with which Logic is conversant. For
all that is out of classification, — all that has no reference to genus and species,
is out of Logic, indeed out of Philosophy ; for Philosophy tends always to the
universal and nccessjrry. Thus the highest canons of deductive reasoning, the
Dicla de Omni et de Nullo, were founded on, and for, the procedure from the
universal whole to the subject parts ; whilst, conversely, the principle of in-
ductive reasoning was established on, and for, the (real or presumed) collection
of all the subject parts as constituting the universal whole. — 2°, The integrate
or mathematical whole, on the contrary (whether continuous or discrete), the
philosophers contemned. For whilst, as Aristotle observes, in mathematics
genus and species are of no account, it is, almost exclusively, in the mathemat-
ical whole that quantities are compared together, through a middle term, in
neither premise, equal to the whole. But this reasoning, in which the middle
term is never universal, and the conclusion always particular, is, as vague,
partial, and contingent, of little or no value in philosophy. It was accord-
ingly ignored in Logic ; and the predesignations more, most, etc., as I have
said, referred to universal, or (as was most common) to particular, or to neither,
/quantity.* This discrepancy among logicians long ago .attracted my attention ;
rtnd I saw, at once, that the possibility of inference, considered absolutely, de-
pended exclusively on the (juantifications of the middle term, in both premises,
!)eing, together, more than its possible totality — its distribution, in anyone.
At the same time I was impressed — 1°, With the almost utter inutility of
1 [Cf. Corvinus, Tnstit. Phil. c. v. f 876, p. Syst. Log. i 360. W.allis, Instit. Log. L. il 0.
123. leiije, 1742. Rcusch, WalU?.) [Keufch, 4, p. 100. 6th ed. — Ed ]
APPENDIX. 587
such reasoning, in a philosophical relation ; and, 2°, Alanned with the load of
valid moods which its recognition in Logic would introduce. The mere quan^
tification of the predicate, under the two pure quantities of definite and indefi-
nite, and the two qualities of affirmative and negative, gives (abstractly) in each
figure thirty-six valid moods ; which (if my present calculation be correct)
would be multiplied, by the introduction of the two hybrid or ambiguous quan-
tifications of a majority and a half, to the fearful amount oi four hundred and
eighty valid moods for each figure. Though not, at the time, fully aware of the
strength of these objections, they, however, prevented me from breaking down
the old limitation ; but as my supreme canon of Syllogism proceeds on the
mere formal possibility of reasoning, it of course comprehends all the legitimate
forms of quantification. It is : — What worst relation of subject and predicate
subsists between either of two terms and a common third term, tvith which one, at
least, is positively related; that relation subsists between the two terms themselves:
in other words, — In as far as two notions both agree, or, one agreeing, the other
disagrees, with a common third notion; insofar those notions agree or disagree
with each other. This canon applies, and proximately, to all categorical syllo-
gisms,— in extension and comprehension, — affirmative and negative, — and
of any figure. It determines all the varieties of such syllogisms : is developed
into all their general, and supersedes all their special, laws. In short, without
violating this canon, no categorical reasoning can, formally, be wrong. Now,
this canon supposes that the two extremes are compared together through the
same common middle ; and this cannot but be if the middle, whether subject or
predicate, in both its quantifications together, exceed its totality, though not
taken in that totality in either premise.
But, as I have stated, I was moved to the reconsideration of this whole mat-
ter ; and it may have been Mr. De Morgan's syllogism in our correspondence
(p. /1 9) which gave the suggestion. The result was the opinion, that these two
quantifications should be taken into account by Logic, as authentic forms, but
then relegated, as of little use in practice, and cumbering the science with a
superfluous mass of moods.'
A UTHOS'S DOCTRIXE - continved.
No syllogism can be formally wrong in which (1°), Both premises are not
negative; and (2°), The quantifications of the middle term, whether as sub-
ject or predicate, taken together, exceed the quantity of that term taken in its
whole extent. In the former case, the extremes are not compared together ; in
the latter, they are not necessarily compared through the same third. These
two simple rules (and they both flow from the one supreme law) being obeyed,
no syllogism can be bad, let its extremes stand in any relation to each other
as major and minor, or in any relation to the middle term. In other words, its
premises may hold any mutual subordination, and may be of any Figure.
On my doctrine. Figure being only an unessential circumstance, and every
proposition being only an ecjuation of its terms, we may discount Figure, etc.,
I Extract from A Letter to A. tie Morgan, Esq., from Sir W. Hamilton, p. 41. — Ed.
688
APPENDIX.
altogether ; and instead of the symbol (mm*- — •) marking sijbject %ed predi'
cate, we might use the algebraical sign of e<[uaUty (=?=)•
The rule of the logicians, that the middle term should be once at le^t di^^
tributed [or indistributable] (i. e., taken universally or singularly = definitely),
is untrue. For it is sufficient if, in both the premises together, its quantification
be more than its quantity as a whole (Ultratotal). Therefore, a major part (a
viore or most) in one premise, and a half in the other, are sufficient to make it
effective. It is enough, for a valid syllogism, that the two extreme notion9
should (or should not), of necessity, partially coincide in the third or middle
notion ; and this is nei.'essarily shown to be the case if the one extreme coin-i
cide with the middle to the extent of a half (Dimidiate Quantification) ; and
the other to the extent of aught more than a half (Ultradieiidiate Quantifica-
tion). The first and highest quantification of the middle term ( : ) •* sufficient,
not only in combination with itself, but with any of all the three inferior. The
second ( . , ) suffices in combination with the highest, with itself, and with the
third, but not with the lowest. The third ( . ) suffices in combination with
either of the higher, but not with itself, far less with the lowest The fourth and
lowest ( , ) suffices only in combination with the highest. [1. Definite ; 2. In-
definito-definito ; 3. Semi-definite ; 4. Indefinite.]
(\at March, 1847. — Yery carefully authenticated.)
There are 4 quantities ( , | . | ., | :), affording (4x4) 16 possible double quan-
tifications of the middle term of a syllogism.
S
M.
,,M. I :M
,M:
Of these 10 are legitimate equivalents (: M ;
4 6
: M , I , M : | . , M . , j . , M . | . M . , ) ; and 6 illegitimate, as not, together, nece*-
sarilv exceeding ilio quantity of that term, taken once in its full extent ( . ,M ,
|,M.,|.M.|.M,l,M.|,]vi,).
Each of these 16 quantified middle terms affords 64 possible moods; to wit,
16 affirmative, 48 negative ; legitimate and illegitimate.
Altogether, these 16 middle terms thus give 256 affirmative and 768 negative
moods ; which, added together, make up 1024 moods, legitimate and illegitimate,
(or each figure. For all three figures = 3072.
The 10 legitimate quantifications of the middle term afford, of legitimate
moods, 160 affirmative and 320 negative (=480), i. e., each 16 affirmative and
32 negative moods (=48); besides of illegitimate moods, from double nega-
tou, 160, L e., each 16. The 6 illegitimate quantifications afford, of affirmative
moods, 96 ; of simple negative moods, 192 ; of double negative mood$, 96 (=
384). Adding all the illegitimates = 544.
The 1024 moods, in each figure, thus afford, of legitimate, 480 moods (1440
for all 3 Figs.); being of affirmative 160(480 for 3 Figs.), of negative 320
(960 for 3 Figs.), of illegitimate 544 pioods ; there being excluded in each,
from inade<|uate distribution alone (§), 288 moods (viz., 96 affirmative, 192
negative) ; from double negation alone (J), 160 moods; from inadequate dis-
tribution and double negation together (§J), 96 moods.
APPENDIX. 589
(e) MNEMONIC VERSES.
A it affirms of this, these, all —
Whilst E denies of any:
I, it affli-ms, whilst O denies,
Of some (or few or many).
Thus A affirms, as E denies.
And definitely either:
Thus I affirms, as O denies.
And definitely neither.
A half, left semi-definite,
Is worthy of its score;
U, then, affirms, as Y denies,
This, neither less nor more.
Indefinito-definites,
To IJI and YO we come ;
And that affii-ms, and tliis denies.
Of more, most (half plus some).
"Dl iand YO may be called Indefinite-definite, either (1*). Because they ajy-
proximate to the whole or definite, [forming] more than its moiety, or (2*^),
Because they include a half, which, in a certain sense, maybe regarded as
definite, and something, indefinite, over and above.
YII.
INDUCTION AND EXAMPLE.
(See p. 225.)
I. -^ Quotations from Authors.
(a) ARISTOTLE.
Aristotle, Prior Analytics, B. ii. c. 23. After stating that " we believe all
things either through [deductive] Syllogism or from Tnductioi»," he goes on to
expound the nature of this latter process.
" Now, Induction, and the Syllogism from Induction, is the inferring one
extreme [the major] of the middle through the other; if, for instance, B is the
middle of A C, and, through C, we show that A inheres in B. Thus do we
institute Inductions. In illustration : — I^et A be long-lived, B, icanting-bile,
and C, individual long-lived animals, as vian, horse, mule, etc. A, then, inheres
in the whole of C (for all animal without bile is [at least some] long-lived) ; but
o90
APPENDIX.
B, wanting hile, also [partially, at least] inheres in all C.^ If now C reciprocate
with B, and do not go beyond that middle [if C and B, subject and predicate,
are each all the other], it is of necessity that A [some, at least] should inhere
in [all] B. For it has been previously shown,* that if any two [notions] inhere
in the same [remote notion], and if the middle' reciprocate with either [or
1 I have, however, doubts whether the ex-
ample which now stands in the Organon be
tliat wliich Aristotle himself proposed. It
appears, at least, to have been considerably-
modified, probably to bring it nearer to wliat
was subsequently supposed to be the truth.
This I infer as likely from the Commentary
of Ammoiiius on the Prior Analytics, occa-
sionally interpolated by, and thus erroneously
quoted under the name of a posterior critic,
— Joannes, surnamed Philoponus, etc. His
words aie, in reference to Aristotle, as fol-
lows: ^'" He wishes, through an example, to
illustrate the Inductive process; it is of this
intent. Let A be long-lived ; B, wanting bile;
C, as crow, and the like. Now, he says, that
t.'ie rrow and the stag, being animals without
bile and long-lived, therefore, animal want-
ing bile is long-lived. Thus, through the last
[or minor] do we connect the middle terra
with the [major] extreme. For I argue thus:
— the individual animals wanting bile are
[all] long-lived; consequently, [all] animals
wanting bile are long-lived." F. 107, a. ed.
Aid. Compare also the greatly later Leo
Magentinus, on the Prior Analytics, f. 41, a.
cd. Aid. On the age of Magentinus, histori-
ans (as Saxius and Fabricius) vary, from the
teventli century to the fourteentli. He was
certainly subsequent to Michael Psellus, ju-
nior, whom he quotes, and, therefore, not
before the end of the eleventh century ; whilst
his ignorance of the doctrine of Conversion,
introduced by Boethius, may show that he
could hardly have been so recent as the four-
teenth.
Aristotle, De Part. Anitfial (L. iv. c. 2), says,
"In some animals the gall [bladder] is abso-
lutely wanting, as in the horse, mule, ass,
stag, and roe." .... " It is, therefore, evi-
dent that the gall serves no useful purpose,
but is a mere excretion. Wherefore those of
the ancients say well, who declare that the
cause of longevity is the absence of the gall;
and this from their observation of the soli-
dungula and deer, for animals of these classes
want the gall, and are long-lived." — Hist.
An.,L. ii c. 11, Schn. 18, Seal. 15vul. Notices
that some animals have, others want, the
gall-bladder (xoA.^j.v. Schn.iii. p. 106), at the
liver. Of the latter, among viviparous quad-
rupeds, he notices stag, roe, horse, mule, ass,
etc. Of birds who have the gall-bladder
aparl from the liver" and attached to the in-
testines, lie notices the pigeon, crow, etc.
- Aristotle refers to the chapter immedi-
ately preceding, which treats of the Kecipro-
cation of Terms, and in that to the fifth rule
which he gives, and of the following purport:
"Again, when A and B inhere in all C [t. e.,
all C is A and is B], and when C reciprocate*
[i. e.,is of the same extension and comprehen-
sion] with B, it is necessary that A should
inhere in all B [i. e., that all B should be A]."
3 For &Kpov, 1 read fieffov; but perhaps the
true lection is — irphs tovto ^irepoi' abrijov
avriffrpf(pri rwu &Kpa)v. The necessity of an
emendation becomes manifest from the slight-
est consideration of the context. In fact, the
common reading yields only nonsense, and
this on sundry grounds. — 1°, There are three
things to which ^artpoy is here applicable,
and yet it can only apply to two. But if lim-
ited, as limited it must be, to the two inhe-
rents, two absurdities emerge. 2°, For the
middle, or common, notion, in which both
the others inhere, that, in fact, here exclu-
sively wanted, is alone excluded. 3°, One,
too, of the inherents is made to reciprocate
with either; that is, with itself, or other. i°,
Of the two inlierents, the minor extreme is
that whicli, on Aristotle's doctrine of Induc-
tion, is alone considered as reciprocating with
the middle or common term. But, in Aris-
totle's language, to &Kpoy, " The Extreme," is
(lilce f] Tt-p6Taaii, The Proposition in the com-
mon language of the logicians) a synonyme
for the major, in opposition to, -and in exclu-
sion of, the minor, term. In the two short
correlative chapters, tlie present and that
which immediately follows, on Induction
and on Example, the expression, besides the
instance in question, occurs at least seven
times ; and in all as the major term. — 5°, The
emendation is required by the demonstration
itself, to which Aristotle refers. It is found
in the chapter immediately preceding (J 5),
and is as follows: — " Again, when A and B
inhere in all C, and when C reciprocates with
B, it necessarily follows that A should [par-
tially, at least] inhere in all B. For whilst A
[some, at least] inheres in all C, and [all] C,
by rea.«on of their reciprocity, inheres in [ali]
B; A will also [some, at least] inhere in all B."
The mood here given is viii. of our Table.
{See Appendix XI.)
(
APPENDIX. 591
with both], then will the other of the predicates [the syllogism being in the
third figure] inhere in the co-reciprocating extreme. But it behooves us to
conceive C as a complement of the whole individuals ; for Induction has its
inference through [as it is of] all.^
" This kind of syllogism is of the primary and immediate proposition. For
the reasoning of things mediate is, through their medium, of things immediate,
through Induction. And in a certain sort. Induction is opposed to the [Deduc-
tive] Syllogism. For the latter, through the middle term, proves the [major]
extreme of the third [or minor] ; whereas the former, through the third [or
minor term, proves] the [major] extreme of the middle. Thus [absolutely],
in nature, the syllogism, through a medium, is the prior and more notorious ;
but [relatively] to us, that through Induction is the clearer." •
An. Pr., L. ii. c. 24. Of Example. — § 1. " Example emerges, when it is
shown that the [major] extreme inheres in the middle, by something similar to \
the third [or minor term] § 4. Thus it is manifest that the /
Example does not hold the relation either of a whole to part [Deduction], nor '^
of a part to whole [Induction], but of part to part; when both are contained
under the same, and one is more manifest than the other. § 5. And [Example]
differs from Induction, in that this, from all the individuals, shows that the
[major] extreme inheres in the middle, and does not [like Deduction] hang the
syllogism on the major extreme ; whereas that both hangs the syllogism [on the
major extreme], and does not show from all the individuals [that the major
extreme is inherent in the minor.] "
An. Post., L. i. c. 1, § 3. — " The same holds true in the case of reasonings,
whether through [Deductive] Syllogisms or through Induction ; for both ac-
complish the instruction they afford from information foreknown, the former
receiving it as it were from the tradition of the inteUigent, the latter manifest-
ing the universal through the light of the individual." (Pacii, p. 413. See the
rest of the chapter.)
An. Pos., L. i. c. 18, § 1. — " But it is manifest that, if any sense be want-
ing, some relative science should be wanting likewise, this it being now impos-
sible for us to apprehend. For we learn everything either by induction or by
demonstration. Now, demonstration is from universals, and induction from
particulars ; but it is impossible to speculate the universal unless through in-
duction, seeing that even the products of abstraction will become known to us
by induction."
A. Aristotle's Errors regarding Induction.
Not making Syllogism and its theory superior and common to both Deduc-
tive and Inductive reasonings.
A corollary of the preceding is the reduction of the genus Syllogism to its
species Deductive Syllogism, and the consequent contortion of Induction to
Deduction.
I This requisite of Logical Induction, — immediately following, in which he treats the
that it should be thought as the result of an reasoning from Example. See passage quoted
agreement of all the individuals or parts, — on page 590 (j 6).
is further shown by Aristotle in the chapter
592
APPENDIX.
B. Omissions.
Omission of negatives.
Of both terms reciprocating.
C. Ambiguities.
Confusion of Individuals and Particular. See Scheibler [_Opera Logica, P.
iii. De Prop., c. vi., tit. 3, 5. — Ed.].
Confusion or non-distinction of Major or Minor extremes.
The subsequent observations are intended only to show out Aristotle's au-
thentic opinion, which I hold to be substantially the true doctrine of Induction ;
to eipose the multiform errors of his expositors, and their tenth and ten times
tenth repeaters, would be at once a tedious, superfluous, and invidious labor.
I shall, first of all, give articulately the correlative syllogisms of Induction and
Deduction which Aristotle had in his eye ; and shall employ the example which
now stands in the Organon, for, though physiologically false, it is, nevertheless
(as a supposition), valid, in illustration of the logical process.
ABIBTOTLE'S CORSEUITIVE SYLLOGISMS,
(a) Ol- INDUCTIOH. (6) Of DEDUCnOIf.
AU C {man, horse, mule, etc. ) is some A {long- AU A {rcanting-bile) is some A {long-lived) ;
lived) ; All C {man, horse, mule, etc.) is all B {uxmt-
AU C {man, horse, mtde, etc.) is all B {uxznt- ing-bUe);
ing-bile) ; AU C {man, horse, mule, etc. ) is some A {long-
All B {waniing-bile) is some A {long^ved). lived).
A,
C (p, q, r, etc.) ;
•:B A, ■;B: it C (p, q, r, etc.)
These syllogisms, though of different figures, fall in the same mood ; in our
table they are of the eighth mood of the third and first Figures. Both un-
allowed. (See Ramus, quoted below, p. 593.)
The Inductive syllogism in the first figure given by Schegkius, Pacius, the
Jesuits of Coimbra, and a host of subsequent repeaters, is altogether incompe-
tent, so far as meant for Aristotle's correlative to his Inductive syllogism in the
tliird. Neither directly nor indirectly does the philosopher refer to any Induc-
tive reasoning in any other figure than the third. And he is right; for the
third is the figure in which all the inferences of Induction naturally run. To
reduce such reasonings to the first figure, far more to the second, is felt as a
contortion, as will be found from the two following instances, the otie of which
is Aristotle's example of Induction, reduced by Pacius to the first figure, and
the other the same example reduced by me to the second. I have taken care
also to state articulately what are distinctly thought, — the quantifications of
the predicate in this reasoning, ignored by Pacius and logicians in general, and
APPENDIX. 593
aduiittcd only on compulsion, among others, by Derodon (below, p. 594), and
the Coimbra commentator.'
ARISTOTLE S INDUCTIVE SYLLOGISM IN FIGURES.
(e) Fio. I. (rf) Fio. II.
All C (man, horse, mule, etc.) is some A (long- Some A (long-lived) is all C (man, horse,
lived); mule, etc.);
AH B (wanting-bile) is all C (man, horse, AU B (imnting-bile) is all C (man, horse,
mule, etc. ) ; mtde, etc. ) ;
All B (toanttng-bile) is some A (long-lived). All B (uxinting-bile) is some A (long-lived).
(b) PACHYMERES.
Pachymeres, Epitome of Aristotle's Logic (Title viii. ch. 3, c. 1280). — " In-
duction, too, is celebrated as another instrument of philosophy. It is more
persuasive than Deductive reasoning, for it proposes to infer the universal
from singulars, and, if possible, from all. But as this is frequently impossible, .
individuals being often in number infinite, there has been found a method
through which we may accomplish an Induction, from the observation even of
a few. For, after enumerating as many as we can, we are entitled to call on
our adversary to state on his part, and to prove, any opposing instances.
Should he do this, then [for, 'data instantia, cadit inductio'] he prevails; but .
should he not, then do we succeed in our Induction. But Induction is brought
to bear in the third figure ; for in this figure is it originally cast. Should, then, ,
the minor premise be converted, so that the middle be now predicated of all
the minor extremes, as that e.xtreme was predicated of all the middle ; in that
case, the con<lusion will be, not of some, but of all. [In induction] the first
figure, therefore, arises from conversion, — from conversion of the minor prem-
ise, — and this, too, converted into all, and not into sojyie. But [an inductive
syllogism] is drawn in the third figure, as follows : — Let it be supposed that
we wish to prove, — every animal moves the lower jaw. With that intent, we
place as terms : — the major, moves the under jaw; the minor, [a//] animal;
and, lastly, the middle, all contained under animal, so that these contents recip-
rocate with all animal. And it is thus perfected [?] in the first figure, as
follows: — To move the lower jato is predicated of all individual animals; these
all are predicated of all animal; therefore, moving the lower jaw is predicated
of all animal. In such sort induction is accomplished."
(e) RAMUS.
Ramus, Scholce Dialecticce, L. viii. (?". 11. " Quid vero sit inductio perobscure-
[Aristoteli] declaratur : nee ab interpretibus intelligitur, quo modo syllogisinus
I)er medium concludat majus extremum de minore : inductio majus de medio
?.
1 [In An. Prior, L. ii. p. 403. Cf. I'erionius, DidUctica, L. iii. p. 366 (1544). Tosca, Comp^.
riiU Logica, t. I. 1. iii. c. 1, p. 115 ]
75
^
APPENDIX.
per minus." Kamus has confirmed his doctrine by his example. For, in his
expositions, he himself is not correct.
(d) DERODON.
Derodon, Logica Restituta, 1659, p. 602. Philosophia Contracta, IGGi, Logica,
p. 91. " Induction is the argumentation in which, from all the particulars,
their universal is inferred ; as — Fire, air, water, earth, are bodies ; therefore,
every element is body. It is recalled, however, to syllogism, by assuming all the
particulars [including singulars] for the middle term, in this manner : — Fire,
air, water, and earth are bodies; Imt jire, air, water, and earth are every element;
there/ore, every element is body. Again : — The head, chest, feet, etc., are dis-
eased ; but the head, chest, feet, etc., are the whole animal ; therefore, the whole
animal i.v diseased. Thus induction is accomplished when, by the enumeration
of all the individuals, we conclude of the species what holds of all its mdi-
viduals ; as — Peter, Paul, James, etc., are rational; therefore, all man is
rational ; or when, by the enumeration of all the species, we conclude of the
genus what holds of all its species ; as — Man, ass, horse, etc., are sensitive ;
therefore, all animal is sensitive ; or when, by the enumeration of all the parts,
we conclude the same of the whole ; as — Head, chest, feet, etc., art diseased ;
Oierefore, the whole animal is diseased."
(*) THE COLLEGE OFALCALA.
A curious error in regard to the contrast of the Inductive and the Deductive
syllogism stands in the celebrated Cursus ■Complutensv*, — in the Disputations
on Aristotle's Dialectic, by the Carmelite College of Alcala, 1624 (L. iii. c. 2).
"We there find surrendered Aristotle's distinctions^ as accidental. Induction
and Deduction are recognized, each as both ascending and descending, as both
from, and to, the whole ; the essential diflTerence between the processes being
taken, in the existence of a middle term for Deduction, in its non-existence
lor Induction. The following is given as an example of the descending syllo-
gism of Induction : — All men are animals ; therefore, tliis, and this, and thit,
etc., man is- an animal. An ascending Inductive syll(^sm is obtained from the
preceding, if reversed. Now all this is a mistake. The syllogism here stated
h Deductive ; the middle, minor, and major terms, the minor premise and the
conclusion being confounded together. Expressed as it ought to be, the syllo-
gism is as follows : — All men are (some) aniinals ; thu<, and this, and this, etc.,
arc (constitute) all men ; therefore, this, and thuf, and thit, etc., are (some)
animal. Here the middle term and three propositions reappear ; whilst the
Deductive syllogism in the first figure yields, of course, on its reversal, an
Inductive syllogism in the third.
The vulgar errors, those till latterly, at least, prevalent in this country, —
that Induction is a syllogism in the Mood Barbara of the first figure (with the
minor or the major premise usually suppressed) ; and still more that from a
some in the antecedent we can logically induce an all in the conclusion, —
these, on their own account, are errors now hardly deserving of notice, and
APPENDIX. ^8fe
have been already sufficiently exposed by me, upon another occasion (Edin-
burgh Review, LVII. p. 224 et seq.). \^Discussions, p. 158 et seq. — Ed.]
(/) FACCIOLATI.
Facciolati, Rudimenta Logica, P. iii. c. 3, defines Induction as " a reasoning
without a middle, and concluding the universal by an enumeration of the sin-
gulars of which it is made up." His examples show that he took it for an
Enthymeme. — '■'■Prudence, Temperance, Fortitude, etc., are good habits [these
constitute all virtue"] ; there/ore [a^Z] virtue is a habit."
(g) LAMBERT.
Lambert, Neues Organon, i. § 287. "When, in consequence of finding a
certain attribute in all things or cases which pertain to a class or species
[genus (V)], we are led to affirm this attribute of the notion of the class or
genus ; we are said to find the attribute of a class or genus through induction.
There is no doubt that this succeeds so soon as the induction is complete, or
80 soon as we have ascertained that the class or species A contains under it no
other cases than C, D, E, F, M, and that the attribute B occurs in each
of the cases C, D, E, F, M. This process now presents a formal syllo-
gism in Caspida. For we thus reason —
C, as M!cR as D, E, F, MareoKB;
But A IS either C, or D, or E, or F or M;
Consequently, all A are B.
" The example previously given of the syllogistic mood Caspida may here
serve for illustration. For, to find whether every syllogism of the Second
Figure be negative, we go through its several moods. These are Cesare,
Camestres, Festino, Baroco. Now both the first conclude in E, both the last in
O. But E and O are negative, consequently all the four, and herewith the
Second Figure, in general, conclude negatively.^ As, in most cases, it is very
difficult to render the minor proposition, which has the disjunctive predicate
for its middle term, complete, there are, therefore, competent very few perfect
inductions. The imperfect are [logically] worthless, since it is not in every
case allowable to argue from some to all. And even the perfect we eschew,
whensoever the conclusion can be deduced immediately from the notion of the
genus, for this inference is a shorter and more beautiful."
Strictures on Lambert's doctrine of Induction.
1°, In making the minor proposition disjunctive.
2°, In making it particular.
3°, In making it a minor of the First Figure instead of the Third.
Better a categorical syllogism of the Third Figure, like Aristotle, whom he
does not seem to have been aware of Refuted by his own doctrine in § 230-
1 It Js given in § 285, as follows: "Now every syllogism of the Second Figure ii either in
Cesare, or Camestres, or Festino, or Baroeo ;
"7%e syllogisms, 03 well in Cesare as m Camestres, "Consegitently every tyllogism in the Second Flgan is
Festino, and Baroco, are all negative ; Jfeaative,"
596
APPENDIX.
The recent German Logicians,^ following Lambert (iV. Org. i. § 287), mako
the inductive syllogism a byword. Lambert's example : — " C, as well as D,
E, F M, all are B ; but A is either C, or D, or E, or F, or M ;
there/ore, all A is B." Or, to adapt it to Aristotle's example : — Man, as well
as horse, mule, etc., all are long-lived animals ; hut animal I'oid of gall is either
man, or horse, or mule, etc. ; therefore, all animal void of gall w long-lived.
This, I find, was an old opinion, and is well invalidated by the commentators
of Louvain.*
The only inducement to the disjunctive form is, that the predicate is ex-
hausted without the predesignation of universality, and the First Figure
attained. But as these crotchets have been here refuted, therefore, the more
natural, etc.
Some logicians, as Oxford Crakanthorpe (Logica, 1. iii. c. 20, published
1622, but written long before), hold that induction can only be recalled to a
Hypothetical syllogism. As, — If Sophocles be risible, likeicise Plato and all
oilier men, then all man is risible ; but Socrates is risible, likewise Plato and all
other men; therefore all man is risible. Against the Categorical syllogism in
one or other figure he argues : — " This is not a universal categorical, because
both the premises are singular ; nor a singular categorical, because the conclu-
sion is universal." It is sufficient to say, that, though the subjects of the prem-
ises be singular (Crakanthorpe does not contemplate their being particular),
as supposed to be all the constituents of a species or relatively universal whole,
they are equivalent to that species ; their universality (though contrarj- to
Aristotle's canon) is, indeed, overtly declared, in one of the premises, by the
universal predesignation of the predicate. Our author farther adds, that In-
duction cannot be a categorical syllogism, because it contains four terms ; this
t As Ilcrbart, Lehrbuch iter Logik, i 69,
Twesten, Drobisch, H. Ritter.
I " I am nware of th» opinion of many,
that the singulars in the Inductive syUofnsm
should be enumerated by a disjunctive con-
junction, in 80 much tliat the premises of
such a syllogism are commonly wont to be
thus cast: VVhalsoever is ,Tokn, or Peter, or Paul,
etc., is capable of instruction. But they err,
not observing that the previous proposition
is manifestly equivalent to the following, —
John, and Peter, and Paul, ttc, are capable of
instruction.^^ (Lovanienses, Com. In An. Pr.,
L ii. tr. 3, c. 2, p. 286, ed. 1547; 1st ed., 1555.)
This here said of the major is true of Lam-
bert's minor. The Louvain masters refer
probably [to Versor. etc.] This doctrine, —
that the Inductive syllogism should be drawn
in a disjunctive form, — was commonly held,
especially by the scholastic commentators on
Tctrus Hispanus. Thus Versor (to take the
books at hand), whose Exposition first ap-
peared in 1487, says — " In the fourth place.
Induction is thus reduced to syllogism, seeing
that, in the conclusion of the Induction, there
Are two terma of which the subject forms the
minor, and the predicate the major, extreme
in the syllogism; whilst the singulars, which
have no place in the conclusion, constitute
the middle term. Thus the Induction — Soc-
rates runs, Ptato runs {and so of other men);
there/ore, all man runs, — is thus reduced :
All that is Socrates, or Plato [and so of others),
runs ; but all man is Socrates, or Plato [and so
of others) ; therefore, all man runs. And these
singulars ought to be taken disjunctively, and
disjunctively, not computatively, verified of
their universal." — {In Hisp. Summul. Tr. v.)
The same doctrine is held in the Repara-
tiones of Arnoldus de Tungeri and the Masters
Regent in the Burse (or College) of St. Law-
rence, in Cologne, 1496. (Tr. iii. c. ii., Seo.
Pri.)
It is also maintained in the Copulnti of
Lambertus de Monte, and the other Regents
in the Bursa Montis of Cologne, 1490. They
give their reasons, which are, however, not
worth stating and refbting.
But Tartaretus, neither in his Commenta-
ries on Hispanus nor on Aristotle, mentioiw
this doctrine.
APPENDIX. 69t
quaternity being made by the "aZZ men" (in his example) of the premises
being considered as different from the " all man " of the conclusion. This is
the veriest trifling. The difference is wholly factitious : all man, all men, etc.,
are virtually the same ; and we may indifferently use either or both, in prem-
ises and conclusion.
n. — Material Inddction.
Material or Philosophical Induction is not so simple as commonly stated,
but consists of two syllogisms, and two deductive syllogisms, and one an Epi-
cheirema. Thus :
1- — What is found true of some constituents of a natural class, is to be pre-
sumed true of the whole class (for nature is always uniform) ; a a' a" are some
constituents of the class A ; therefore, what is true of a a' a" is to be presumed
true of A.
II. — Wheit is true of a a' a," is to be presumed true of A ; but z is true of a
a' a ' ; therefore, z is true of A.
It will be observed, that all that is here inferred is only a presumption,
founded, 1°, Qn the supposed uniformity of nature ; 2°, That A is a natural
class ; 3^, On the truth of the observation that a a' a" are really constituents
of that class A ; and, 4°, That z is an essential quality, and not an accidental.
If any be false, the reasoning is nought, and, in regard to the second, a a' a"
(some) cannot represent A (all) if in any instance it is found untrue. '■'■Data
instantia cadit inductio." In that case the syllogism has an undistributed
middle.
598
APPENDIX.
YIIL
HTPOTHETICAL AND DISJUNCTIVE RE ASONING — IMMEr-
DIATE INFERENCE.
I. — Author's Doctrink — Fraohbnts.
(Seep. 231.)
All Mediate inference is one; that incorrectly called Categorical j for tne
Conjunctive and Disjunctive forms of Hypothetical reasoning are reducible to
immediate inferences.
B
Immediate ;
of which some
kinds are
Recognized,
as Propositional.
(Various.)
Not recognized,
as Syllogistic,
/ Disjunctive,
> Hypothetical.
\ Coi\junctive,>
O 04
Mediate;
Syllogism Proper, <
(Categorical.)
A) Analytic.
B) Synthetic.
''a) Unfignred.
'b) Figured,
(Intensive
or Exten-
sive) in
F. I.
F. II.
.F. m..
^1
^
§ 1. Reasoning is the showing oat explicitly that a proposition, not granted
or supposed, is implicitly contained in something different, which is granted or
supposed.
§ 2. What is granted or snpposed is either a single proposition, or more than
a single proposition. The Reasoning in the former case is Immediate, in the
latter Mediate.
§ 3. The proposition implicitly contaifted may be stated first or last. The
Reasoning in the former case is Analytic, in the latter Synthetic.
Observations. — § 1. "A proposition," not a truth ; for the proposition may
not, absolutely considered, be true, but, relatively to what is supposed its
evolution, is and must be necessary. All Reasoning is thus hypothetical ;
hypothetically true, though absolutely what contains, and, consequently,
what is contained, may be false.*
1 Reprinted from Discuaions, p. 656. — Ed.
*Tbat all logical reasoning is hypotheti-
cal, and that Categorical Syllogism is really,
and in a higher signification, hypothetical,
see Maimon, Yersueh einer neutn Logik, f vi. 1.,
APPENDIX. 599
Observations. — § 2. Examples: Immediate — If \ is B, then B « A; Medi-
ate — If ^ i^ B, and B is C, then A is C.
Observations. — § 3. Examples : Analytic — B is A, for A is B ; A is C,for
A is B, and B is C. Synthetic — A is B ; therefore, B is A ; A is B, and
B is C ; therefore, A is C.
ON THE NATCKE AND DIVISIONS OF INFERENCE OR SYLLOGISM IN GENERAL.
(November, 1848.)
I. Inference, what
II. Inference is of three kinds; what I would call the — 1°, Commutative;
2°, ExpUcative ; and, 3°, Comparative.
1°, In the first, one proposition is given; and required what are its formal
commutations ?
2°, In the second, two or more connected propositions are given, under cer-
tain conditions (therefore, all its species are conditionals) ; and required what
are the formal results Into which they may be explicated. Of this genus there
are two species, — the one the Disjunctive Conditional, the other the Conjunc-
tive Conditional. In the Disjunctive (the Disjunctive also of the Logicians),
two or more propositions, with identical subjects or predicates, are given, under-
the disjunctive condition of a counter quality, i. e., that one only shall be affir-
mative; and it is nquired what is the result in case of one or other being
affirmed, or one or more denied. (Excluded Middle.) In the Conjunctive
(the Hypotheticals of the logicians), two or more propositions, convertible or
contradictory, with undetermined quality, are given, under the conjunctive
condition of a correlative quality, i. e., that the affirmation or negation of one
being determined, determines the corresponding affirmation or negation of the
others ; and it is required what is the result in the various possible cases.
(Identity and Contradiction, not Sufficient Reason, which in Logic is null as a
separate law.)
3°, In the third, three terms are given, two or one of which are positively
related to the third, and required what are the relations of these two terms to
each other ? '
III. All inference is hypothetical.
IV. It has been a matter of dispute among logicians whether the class which
pp. 82, 88. E. Rejnhold, Log-ii, ( 109, p. 263 1 A better statement of the tliree different
tt xfq. Smiglecius, Logica, Disp. xiii. q. 6, processes of Reasoning,
p. 496 (1st ed. 1616). I. Given a proposition; commutative^ —
On the nature of the Necessity in Syllogistic what are the inferences which its commuta-
Inference; distinction of Formal and Mate- tions afford?
ritLlJiecesmty, or of necessitas consequenticp and II Given two or more propositions; re-
nteessitas congequentif, Me Scotus", Qitcpstiones, lated and conditionally; — what are the in-
Super Elenchos, qu. iv., 227, od 1639, and that ferences which the relative propositions,
all inference hypothetical, In An. Prior, L. ii. explicated under these conditions, afford?
qu. i. p. 331. Apuleius, De Hah. Doct. Plat., p. III. Given three notions; two related, and
34. Aristotle, An. Prior, i. 32, i 5. Smiglecius, at least one positively, to a third ; — what are
Logica, lot. eit. Balforeus', In Arist. Org., An. the inferences afforded in the relations to
Prior,!, t. 8, p. 454,1616. [See also Discus- each other, which this comparison of the tWO
siotts, p. 146, note. — Ed.] notions to the third determines?
600 APPENDIX.
I call Explicative (viz., the Hypothetical and Disjunctive Syllogisms) be of
Mediate or Immediate inference. The immense majority hold them to be me-
diate ; a small minority, of which I recollect only the names of Kant [Fischer,
Weiss, Bouterwek, Herbart],' hold them to be immediate.
The dispute is solved by a distinction. Categorical Inference is mediate, the
medium of conclusion being a term; the Hypothetical and Disjunctive syllo-
gisms are mediate, the medium of conclusion being a proposition, — that which
I call the Explication. So far they both agree in being mediate, but they differ
in four points. The first, that the medium of the Comparative syllogism is a
term ; of the Explicative, a proposition. The second, that the medium of the
Comparative is one ; of the Explicative, more than one. The third, that in the
Comparative the medium is always the same ; in the Explicative, it varies
according to the various conclusion. The fourth, that in the Comparative the
medium never enters the conclusion ; whereas, in the Explicative, the same
proposition is reciprocally medium or conclusion.
V. Logicians, in general, h^ve held the Explicative class to be composite
syllogisms, as compared with the Categoric ; whilst a few have held them to be
more simple. This dispute arises from each party taking a partial or one-sided
view of the classes. In one point of view, the Explicative are the more com-
plex, the Comparative the more simple. In another point of view, the reverse
holds good.
Our Hypothetical and Disjunctive Syllogisms may be reduced to the class of
Explicative or Conditional. The Hypotheticals should be called, as they were
by Boethius and others, Conjunctive, in contrast to the coordinate species of
Duy'unctive. Hypothetical, as a name of the species, ought to be abandoned.
The Conjunctive are conditional, inasmuch as negation or affirmation is not
absolutely asserted, but left alternative, and the quality of one proposition is
made dependent on another. They are, however, not properly stated. The
first proposition, — that containing the condition, — which I would call the
Explicand, should be thus enounced : ^s B, so A ; — or. As B is, so is A ; or,
Aa C is B, .vo is B A. Then follows the proposition containing the explication,
which I would call the Explicative ; and, finally, flie proposition embodying the
result, which I would call the Explicate.
They are called Conjunctives from their conjoining two convertible proposi-
tions in a mutual dependence, of which either may be made antecedent or
consequent of the other.
Disjunctive syllogisms are conditional, inasmuch as a notion is not absolutely
asserted as subject or predicate of another or others, but alternatively conjoined
with some part, but only with some part, of a given plurality of notions, the
affirmation of it with one part involving the negation of others. Tlie first
proposition, containing the condition, I would call the Explicand, and so forth
as in the Conjunctives. They are properly called Disjunctives.
(1 Kant, Logik, i 76. Bouterwek, Lehrbwh 187. Weiss, Logik, n 210, 251. IIerb«rt,
der philosophisehfn Yorkenntnifse, } 100, p. 168, Lehrbuck zur Einititung in die Philosopkit, i (H,
ad ed. 1820. Fischer, Loffti;, c. v. H 99, 100, p. p. 87, 1834.]
APPENDIX. 601
DISTRIBUTION OF REASONINGS.
(Nov. 1848). — Inference may be thus distributed, and more fully and accu-
rately than I have seen. It is either (I.) Immediate, that is, without a middle
term or medium of comparison ; or (II.) Mediate, with such a medium.*
Both the Immediate and the Mediate are subdivided, inasmuch as the reason-
ing is determined (A) to one, or (B) to one or other, conclusion. (It is mani-
fest that this latter division may constitute the principal, and that immediate
and mediate may constitute subaltern classes.)
All inference, I may observe in the outset, is hypothetic, and what have been
called Hypothetical Syllogisms are not more hypothetic than others.
LA — Immediate Peremptory Inference, determined one conclusion, con-
tains under it the following species:*
I. B — Immediate Alternative Inference contains under it these five spe-
cies, —
1°, Given one proposition, the alternative of affirmation and negation. As
— A either is or is not ; but A is ; therefore, A is not not. Or, A is or is not B ;
but A is B ; therefore, A is not nof-B.
This species is anonymous, having been ignored by the logicians; but it
requires to be taken into account to explain the various steps of the process.
2°, Given one proposition, the alternative between different predicates. This
is the common Disjunctive Syllogism.
3°, The previous propositions conjoined, given one proposition, etc. As, A
either is or 'is not either B wr C or D ; hut A is B ; therefore, it is not nol-^, it is
not C, it is not D.
Alias, A is either B or non-B, or C or non-C, or D or non-D ; but A ts B ;
therefore it is not ?Jon-B, and it ts 7ion-C, and it is non-D.
4", Given two propositions, second dependent on the first, and in the first the
alternative of affirmation and negation. This is the Hypothetical Syllogism of
1 [Cf. Fonseca, Instit. Dial., L. vi. c. 1., 1st reinen Lo^ik, § 130, p. 391. Scheibler, Op.
ed. 1564. Eustachius, Surrnua Philosopkim Log., De Proposit. Consecutione, p. 49*2 tl sey.]
Quo'tri partita, Dialectica, P. jii. tract, i., p. 2 [Kinds of Immediate Inference. I. Sub-
112. [•' Quoniam argumentatio est quasdam alternation. II. Conversion. III. Opposi-
consequentia (latius enim patet consequentia tion — (a) of Contradiction — (b) of Contra-
quam argumentatio), prius de consequentia, riety — (c) of Subcontrariety. IV. Equipol-
quam de argumentatione dicendura est. lence. V. Modality. VI. Contraposition.
Consequentia igitur, sive consecutio, est ora- VII. Correlation. VIII. Identity,
tio in qua ex aliquo aliquid colligitur; ut, Fonseca (IV), (I),(II). Eustachius (I), (IV),
Omnis homo est animal, igitur aliguis homo est (II), (VIII.) Wolf, (IV), (VII), (III), a, b, c,
animal." — 'Ed.] [Whether Immediate Infer- (II). Stattler, (I), (IV), (II), (III) Kant, (I),
ence really immediate, see, on the affirmative, (III), a, b, c, (II), (VI). E. Reinhold, (I), (II),
E. Reinhold, Logik, f 106; on the negative, (VI), (VII). Rosling, (I), (IV), (II), (III), a.
Wolf, Phil. Rat., i 461. Krug, Logik, § 94, p. b, c, (V). Krug, (IV), (I), (III), a, b. c, (II),
287. Schulze, Log-iA:, 5§ 85-90'(§ 80, 5th ed.). (V). G. E. Schiilze, (IV), (I), (III), (II). S.
(St. MtLimon, Versuck einerneuen Logik, Sect. V. Maimon, (1), (III), (II), (VI). Bachmaiiii,
i 2, p. U et seq. F. Fischer, Log'i/t, p. 104 er (IV), (I). (Ill); a, b, c, (II), (VI), (V).
sell. Bachmann, Logik, f 105, p. 154 e/ seq. Plainer, (I), (II), (III), (IV). F. Fischer, (V),
Reimarus, VemunfiUhre, } 159 et seq. (1765). (I), (III), (II), (VI) Reimarus, (IV), (I),
Bolzano, Wi.^stnsdiaftslthre, Logik, \o\. M. i, (III), a, b, (II). Twesten. (I), (V), (III), (IV),
255 ft seq. Twesten, Logik, insbeson'lere die (II), (VI). See pp. 634, 535]
Analytik, j 77, p. 66. Rbsliug, Die Lrhnn der '
76
602
APPENDIX,
the logicians. It is, however, no more hypothetical than any other form of
reasoning ; the so-called hypothetical conjunction of the two radical propositions
being only an elliptical form of stating the alternation in the one, and the de-
pendence on that alternation in the other. For example : If A is B,B is C;
this merely states that A either is or is not B, and that B is or is not C, accord-
ing as A is or is not B. In short — As A is or is not B, so B is or is not C.
(Errors, — 1**, This is not a mediate inference.
2°, This is not more composite than the categorical.
3°, The second proposition is not more dependent upon the first than the
first upon the second.)
5°, Given two propositions, one alternative of affirmation and negation, and
another of various predicates ; the Hypothetieo-disjunotive or Dilemmatic
Syllogism of the logicians.
II. A — Mediate Peremptory Inference. This is the common Categorical
Syllogism. Three propositions, three actual terms, one primary conclusion, or
two convertible equally and conjunctly valid.
II. B — Mediate Alternative Syllogism. Three propositions, three possible
terms, and conclusions varying according ....
2°, The Disjunctive Categorical.
4°, The Hypothetical Categorical.
5°, Hypothetico-Disjunctive CategoricaL
HYPOTHETICAL STLLOGISH. — CANON.
(Oct. 1848.) — Canon — Two or more propositions thought as indetermined
in quality, but as in quality mutually dependent, the determination of quality in
the one infers a determination of the corresponding quality in the other.
This canon embodies and simplifies the whole mystery of Hypothetical Syl-
logisms, which have been strangely imphcated, mutilated, and confused by the
logicians.
1", What are called Hypothetical Propositions and Syllogisms are no more
hypothetical than others. They are only hypothetical as elliptical. When we
say, If A is, then B is, we mean to say the proposition, A is or is not, and the
proposition, 'B is or is not, are mutually dependent, — that as the one so the
other. If here only means taking for the nonce one of the qualities to the
exclusion of the other ; I, therefore, express in my notation the connection of
the antecedent and consequent of a hypothetical proposition, thus :
(A
-) = (Bx,
2**, The interdependent propositions are erroneously called Antecedent and
Consequent. Either is antecedent, either is consequent, as we choose to make
them. Neither Is absolutely so. This error arose from not expressing overtly
the quantity of the subject of the second {)roposItIon. For example : If man is,
then animal is. In this proposition, as thus stated, the negatiod of the first does
APPENDIX.
603
not infer the negation of the second. For man not existing, animal might be
realized as a consequent of dog, horse, etc. But let us consider what we mean ;
we do not mean all animal, but some only, and that so7ne determined by the
attribute of rationality or such other. Now, this same some animal depends on
man, and man on it ; expressing, therefore, what we mean in the proposition
thus : — If all man is, then some animal is, — we then see the mutual dependence
and convertibility of the two propositions.* For to say that no animal is, is
not to explicate but to change the terms.
3°, The interdependent propositions may be dependent through their counter
qualities, and not merely through the same. For example : .4s our hemisphere
is or is not illuminated, so the other is not or is ; but the other is not illuminated ;
therefore ours is. Another : If A is, then B is not; but B is; therefore A is not.
DISJCNCTIVB AND HYPOTHETICAL SYLLOGISMS PROPER.
Aristotle ignores these forms, and he was right* His followers, Theophras-
tus and Eudemus, with the Stoics, introduced them into Logic as coordinate
with the regular syllogism ; and their views have been followed, with the addi-
tion of new errors, up to the present hour. In fact, all that has been said of
them has been wrong.
1°, These arc not composite by contrast to the regular syllogism, but more
simple.
2°, If inferences at all, these are immediate, and not mediate.
3°, But tliey are not argumentations, but preparart;ions (explications) for
argumentation.^ They do not deal with the quaesitum, — do not settle it ; they
1 Cf. Titius, Ars Cogitandi, c. xii. § 26. " In
specie falsum quoque arbitror, quod Syllo-
gismi Conditionales duas habeant figuras, quae
his muniantur regulis, (1) posito antecedente,
ponitur consequens, non vero remoto antecedente,
removetuT consequens^ (2) remoto conseqtiente,
removetur antecedens, non autem posito conse-
guente, ponitur uiUecedens, ... § 28. Vide-
amus specialius ; contra primam regulam sic
peccatur:
Si Chinenses sunt Mahometani, sunt infideles,
At non sunt Mahometani,
Ergo non sunt infideles,
"nam conclusio hie est absurda! Verum si
prasdicatum conclusionis sumatur particular-
iter, nulla est absurditas, si autem generaliter,
turn evadunt quatuor termini. § 9. Eodem
exemplo secunda regula etiam illustratur, sed
assumemus aliud ex Weisio, d. I.
Si miles est doctus, novit libros (nempe sicut
eruditi solent).
Sed novit libros (scil. ut alii homines, etiam
indocti, nosse solent).
Ergo miles est doctus.
" Hsec conclusio itidem pro .falsa habetur!
8ed jam indicavimus in addita parenthesi
veram causam, r.empe quatuor terminos,
quodsi autem mcdius terminus eodem sensu
tccipiatur, ac in syllogismo formaliter pro-
posito queat minor probari, turn conclusio
erit verissima, idque virtute prsemissarum.
§ 30. Omnis igitur error exinde habet origi-
nem, quod quantitatem prtedicati vel non
intelligant, vel non observent; si igitur hunc
lapsum evites, objecta exempla omnia, qualia
etiam Weisius d. I. commemorat, facile di-
lues." — Ed.
2 Cf. Titius, Ars Cogitandi, c. xii. $ 7. " Syl-
logismus Disjunctivus est enthymema sine
majore, bis, oratione disjuncta et positiva,
propositum, . . . } 17. Conditionalis seu
Hypotbeticus nihil aliud est quam enthy-
mema vel sine majore, vel minore, bis, prima
scil. vice, conditionaliter, secunda, pure, pro-
positum. i 20. Sequitur nullum peculiare
concludendi fundamentum vel formam circa
Syllogismos Conditionales occurrere, nam
argumentationes imperfectas, adeoque mate-
riam syllogismorum regularium illi conti-
nent." — Ed.
3 This I say, for, notwithstanding what M.
St. Hilaire so ably states in refutation of my
paradox, I must adhere to it as undisproved.
— See his Translation of the Organon, vol.
iv. p. 55.
604 APPENDIX.
only put tlie question in the state required for the syllogistic process; this,
indeed, they are frequently used to supersede, as placing the matter in a light
which makes denial or doubt impossible ; and their own process is so evident,
that they might, except for the sake of a logical, an articulate, development of
iill the steps of thought, be safely omitted, as is the case with the quaesitum
itself. For example :
1. Hypothetical (so called) Syllogism. Let the quaesitum or problem be, to
take the simplest instance, — Does animal exist f This question is thus hypo-
thetically prepared — If man ts, animal is. But [as is conceded] man is; there-
fore, animal is. But here the question, though prepared, is not solved ; for the
opponent may deny the consequent, admitting the antecedent. It, therefore,
is incumbent to show that the existence of animal follows that of man, which is
done by a categorical syllogism.
Animal, —i : Man : »' , Existent.
2. Disjunctive (so called) Syllogism. Problem — Is John mortal f Dis-
junctive syllogism — John is either mortal or immortal: but he is not immortal;
ergo [and this, consequently, is admitted as a necessary alternative] he is mortal.
But the [alternative antecedent] may be denied, and the alternative consequent
falls to the ground. It is, therefore, necessary to show either that he is not im-
mortal, or — the necessary alternative — that he is mortal, which is done by
categorical syllogism.
John urn , Man : •— j : Immortal,
• John B^ , Man : ■■ , MortaL
HTPOTHBTIOAL INFERENCE.
Inasmuch as a notion is thought, it is thought either as existing or as non-ex-
isting ; and it cannot be thought as existing unless it be thought to exist in this
or that mode of being, which, consequently, affords it a ground, condition, or
reason of existence. This is merely the law of Reason and Conseijuent ; and
(he hypothetical inference is only the limitation of a supposed notion to a cer-
tain mode of being, by which, if posited, its existence is affirmed ; if sublated,
its existence is denied. For example : If k is, it is B ; hut A is, etc.
Again, we may think the existence of B (consequently of A B) as depen-
dent upon C, and C ns dependent upon D, and so forth. We, accordingly,
may reason : If -k v< B, and B is C, and C is D, etc.
DISJCNCTIVE STLLOOI8M PROPER.
(October 1848.) — Inasmuch as a notion is thought, it is thought as deter-
mined by otu' or other, and only by one or other, of any two contradictory at-
tributes; and inasmucli as two notions are thought as contradictory, the one or
APPENDIX. 605
the other, and only the one or the other, is thought as a determining attribute
of any other notion. This is merely the law of Excluded Middle. The dis-
junctive inference is the limitation of a subject notion to the one or to the other
of two predicates thought as contradictories ; the affirmation of the one infer-
ring the negation of the other, and vice versa. As, A w either B or not B, etc.
Though, for the sake of brevity, we say A is either B or C or D, each of these
must be conceived as the contradictory of every other ; as, B = | C | D, and
so on with the others.
HTPOTHETICAL8 (COKJUNCTIVE AND DISJUNCTIVE STLLOGISW).
(April 30, 1849.) — These syllogisms appear to be only modifications or cor-
ruptions of certain immediate inferences ; for they have only two terms, and
obtain a third proposition only by placing the general rule of inference (stat-
ing, of course, the possible alternatives), disguised, it is true, as the major
premise. It is manifest that we might prefix the general rule to every mediate
inference ; in which case a syllogism would have four propositions ; or, at least,
both premises merged in one complex proposition, thus :
If k and C be either subject or predicate [of the same termf], they are both subject or pred-
icate of each other ;
But B is the subject of A and predicate of B [C?] ;
.•. A is the predicate ofCA
Thus, also, a common hypothetical should have only tico propositions. Let us
take the immediate inference, prefixing its rule, and we have, in all essentials,
the cognate hypothetical syllogism.
1. — Conjunctive Hypothetical.
All B IS {some or all) A; AU men are {some) animals;
Some or all B exists ; {AU or some) men exist ;
Thei-efore, some A exists. Therefore, some animals exist.
Here it is evident that the first proposition merely contains the general rule
upon which all immediate inference of inclusion proceeds ; to wit, that, the sub-
jective part being, the subjective whole is, etc.
Now, what is this but the Hypothetical Conjunctive ?
If B is, A IS ; If man is, animal is ;
But B IS ; But man is ;
Therefore, A is. Therefore, animal is.
1 There seems to be an error here in the C is B, then C is A; but B ts A, andC is Bj
author's M.S. It is obvious that a mediate therefore, C is A. This is apparently what the
inference may be expressed in the form of a author means to express in a somewhat differ-
hypothetical syllogism. Thus: 1/ K is A, and ent form. — Ed.
606 APPENDIX.
2. — Hypothetical Disjunctive.
B is either A or not A; Man is either animal or non<uunidl ;
Bitt B is A ; But man is animal ;
Therefore, ^ is not not-A. Therefore, is not non-animoL
Stating this hypothetically, we may, of course, resolve the formal contradic-
tory into the material contrary. But this is wholly extralogicai.
HYPOTHETICAL. AKD DISJUNCTIVE SYLLOGISMS.
(I848 or 1849.) — The whole antecedent must be granted ; and there can-
not be two propositions inferred. In Categorical Syllogisms, the antecedent is
composed of the major and minor premises, and there is only one simple con-
clusion (though this may, in the second and third figures, vary). So in H\-po-
thetical and Disjunctive Syllogisms the whole antecedent is the two clauses of
the first proposition ; and the whole inference is the first and second clauses of
the second proposition, erroneously divided into minor proposition and conclu-
sion.
(January 1850.) — The Medium or Explicative may be indefinitely various,
according to the complexity of the Explicand ; and so may the Explicate. The
explicative and the explicate change places in different explications. There
is, in fact, no proper medium-explicative or conclusion-explicate.
(January 1850.) — In Disjunctives there is always at least double the num-
ber of syllogisms (positive and negative) of the disjunct members ; and in all
syllogisms Avherc the disjunct members are above two, as there is thus affonled
the possibility of disjunctive explicates, there is another half to be added. Thus,
if there be two disjunct members, as A — x B C, there are four syllogisms, but
all of an absolute conclusion, — explicate. But if there be three disjunct
members, as A — x B C D, in that case there are six absolute explicates, three
positive and three negative, and, moreover, three disjunctivo-positive conclu-
sions, — explicates, after a negative explicative, and so on.
HTPOTHBTICAL SYLLOGISM. — CANOKS.
(February 1850.) — I. For Breadth, — The extensive whole or class being
universally posited or sublated, every subjacent part is posited or sublated ; or,
for Depth, — All the comprehensive wholes being posited or sublated, the com'
prehended parts are universally posited or sublated.
n. For Breadth, — Any subjacent part being posited or sublated, the exten'
sive whole or class is partially posited or sublated ; or, for Depth, — Any com'
prehensive whole being posited or sublated, the comprehended parts (or part)
are, pro tanto, posited or sublated, — Conversion and Restriction.
in. If one contradictory be posited or sublated, the other is sublated or posi-
ted, — Contradiction.
IV. If some or a part only of a notion be posited or sublated, all the rest
(all other some) is sublated or posited, — Integration.
V. If the same under one correlation be posited or sublated, so under the
other, — EquipoUence.
APPENDIX. 607
VI. Law of Mediate Inference,' — Syllogism.
Mem. — The some in the expllcand is (as in the Conversion of propositions)
to be taken in the explicative as the same some. There is thus an inference
equally from consequent to antecedent, as from antecedent to consequent.*
HYPOTHETICALS, OR ALTERNATIVES.
CONJUNCTIVE (HYPOTHETICALS EMPHATICALLY) AND DISJUNCTIVE (ALTERNA-
TIVES EMPHATICALLY.)
(August 1852.)
Quantification, — Any.
Affirmative, — Any (Anytldng, Aught) contains under it every positive
quantification, — All or Every, — Some at least, — Some only, — This, These.
(Best.)
Negative, — Not any, None, No (Nothing, Naught), is equivalent to the most
exclusive of the negations, All not : All or every not ; Not one, and goes be-
jond the following, which are only partial negations, — Not all ; Not some ;
Some not. (Worst.)
Affirmative, — Any, a highest genus and best ; not so Negative — Not any, —
a lowest species, and worst. Therefore can restrict, — subalternate in the
former, not in the latter.
— Any (all or every, — some). Some not, or not some, or not all — some only (def.).
Pure affirmative. Mixed affirmative and negative.
All or every not, not one, not any.
Pure negative.
//" any (every) M be an (some) A, and any {every) A an (some) S, then is any (every) M
an S ; and, v. v., if no (not any) A be any S, and any M some A, ihen is no M any S.
.". (On one alternative), some M beiny some A, and all A some S, some M is some S.
(On the other), no A being any S, and every M some A, no M is any S.
J/" (on any possibility) M is, some A is; or, v. v., if no A is, no M is.
.-. (on one alternative) (in this actuality), some M being, some A is; (on the other), no
A being, no JI is.
Possible M : , i»- — , A oj- A : ^ : M. Supposition of universal Possibility. In
any case.
Actual M , ^ , A or A:^ — :A. Assertion of particular Actuality. Jn this
case.
From Possible, we can descend to Actual ; from Any^ to Some ; but Not any
being lowest or Avorst, we can go [no] lower.
1 See p. 636. — Ed. 2 See p. 603. — Ed.
/
608
APPENDIX.
The Possible indifferent to Affirmation or Negation, it contains both implicitlj.
But when we descend to the Actual (and Potential?), the two qualities emerge.
This explains much in both kinds of Hypothetical or Alternatives, — the
Conjunctives and Disjunctives.
Higher classes, — Possible, Actual — Semper, quandocunque, tunc, nunc —
Ubicunque, ubiqite, ibi, hoc — Any, all, some — In all, every, any case, in this
case — Conceivable, real.
BULES OF HTPOTHETICAL SYLLOGISMS.
1. Universal Rule of Restriction. — What is thought of all is thought of
some, — what is thought of the whole higher notion (genus) is thought of all
and each of the lower notions (special or individual).
2. General Rule of both Hypotheticals. — What is thought (implicidy) of
all, the Possible (genus), is thought (explicitly) of all and each, the Actual
(species).
3. Special Rule of Conjunctives. — What is thought as consequent on every
Possible, is thought as consequent on every Actual, antecedent
4. Special Rule of Disjunctives. — What is thought as only Possible (alter-
natively), is thought as only Actual (alternatively).
5. Most Special Rule of Conjunctives.
6. Most Special Rule of Disjunctives.
HYPOTHETICALS — EXAMPLES DKQUAKTIFIED.
(Higher to Lower.)
Affirmative.
If the genus is, tlie specia is.
If the stronger can, the voeaker can.
Negative.
If the genus is not, the species is not.
If the stronger cannot, the uieaker cannot.
(Lower to Higher.)
If the species is, the genus is. If the species is not, the genus is not.
If the weaker can, the stronger can. If ike weaker cannot, the stronger castnoL
(Equal to Equal.)
If triangle, so trilateral.
Such poet Homer, such poet Vtrgil.
Where {when) the carcass is, there (then)
are the flies.
If Socrates be the son of Sophroniscus, SopA-
roniscus is the father of Socrates.
If equals be added to equals, the wholes are
equal.
If A be father of H, B is son of A;
.•. A being father of B, Bis son of A ;
.'. B not being son of A, A is not father of B.
If the angles be proportional to the sides of
.'. An equiangular will be an equHateral A.
If wheresoever the carcass is, there will the
eagles be gathered together (Matt.
xxiv.28);
.'.If here the carcass is, here, etc.
APPENDIX. 609
A.) — CONJUNCTIVE HYPOTHBTICAIA.
« . ^/. > , -r^ , . (A, being D, is A ;
l.)IfAbeD,UisA;.-.<' ,.' . ^
(A, not being A, is )iotD;
In other words — A is either Dor not A D.
Identity and Contradiction.
n X rr r> >. A •* • < a \ ^> being A, is not nou-A'^
2.) ff Boe A,ittsnotnon-A; .■. i„ , .
( B, being non-A, is not A;
In other loords — B is either A or non-A.
Excluded Middle.
», . r^ T^ i^ . . ■. ■ . ( B, )iot being A, is non-A;
^.)IfJibenotA,ittsnon-A;.-.l'. ' ' '
( B, bemg non-A, is not A;
In other voords — B is either not A or not non-A.
Excluded Middle.
-.. ^ , ^ . . K'E, not being T), is not A:
4.) .ff E 6c not D, U is not Ay .-. \ J , . ^ . '
I E, being A, JsD;
In other words — E is either not D A, or A D.
Contradiction and Identity.
B.) — DI8JONCTIVE HTPOTHETICALS.
B being A, is not non-A ;
B being ;
Excluded Middle.
If B be either A or non-A; .•. ,„,. . .
( B being non-A, is not A
" 7)^ means suppose that, — in case that, — on the supposition — hypothesis,
tinder the condition, — under the thought that, — it being supposed possible ;
.-. etc., means then, — therefore, — in that case, etc., etc., — in actuality either^
Only, properly, in both Conjunctives and Disjunctives, two contradictory
alternatives. For contrary alternatives only material, not formal, and, in point
of fact, either A or B or C means A or non-A, B or non-B, C or non-C
The minor premise, on the common doctrine, a mere materiality. Formally, .
— logically, it is a mere differencing of the conclusion, which is by formal .
aUternative afforded.
1.) In Hypothetieals (Conjunctive and Disjunctive), two or three hypotheses.
The first is in the original supposition of 7)0.s.'ii&//<7?/. (//^B be A, it i.< 7iot non~
A — FfB he either A or non-A.) The second (and third) is in the alternative
suppositions of actualifj/ (.-. either if B be A, it is not non-A, or if B be non-A,,-
U is- not A. — .-. If B be A, it is not non-A, or if B be non-A, it is not A). (Pos-
sibly, — by possible supposition) If man is, animal is; .-. (actually) Man being,
animal is : (or)' animal not being, man is not.
1.) Possibility' — a genus Indiflforent to negative and affirmative. These two-
species of Possibility, to wit, two Actuals, — an actual yes, and an actual no.
The total formal conclusion is, therefore, of two contradictories. This explain*.
77
610 APPENDIX.
why, in Conjunctive and Disjunctive Hj-potheticals, there are two alternative
consequents, and only one antecedent.
2.) In Hypotheticals (Conjunctive and Disjunctive) a division of genus in
ihe first supposition into two contradictories, — species. The inference, there-
fore, one of subalternation or restriction.
3.) In Hypotheticals (Conjunctive and Disjunctive), two alternative contra-
dictory conclusions — the form giving no preference between the two, the mat-
ter only determining (other immediate inferences have only one determinate
conclusion, and all mediate syllogism has virtually only one). Formally, there-
lore, we cannot categorically, determinately, assert, and assert exclusively,
(!ither alternative, and make a minor separate from the conclusion. This only
materially possible ; for we know not, by the laws of thought, whether a cer-
tain alternative is, knowing only that one of two alternatives must be. For-
mally, therefore, only an immediate inference, and that alternative double.
4.) Hypothetical (Conjunctive and Disjunctive) reasoning more marking
out, — predetermining how a thing is to be proved, than proving it
5.) Thus, three classes of inference: 1°, Simple Immediate Inference. — 2**,
Complex Immediate Inference (Hypotheticals Conjunctive and Disjunctive). —
3°, Syllogisms Proper, Mediate Inference.
6.) If we quantify the terms, even the formal inference breaks down.
7.) The only difference between the first proposition and the two latter, is
the restriction or subalternation. These last should, therefore, be reduced to
one, and made a conclusion or restriction. The genera and species are of the
most common and notorious kinds, as Possible and Actual, — Wherever, Here,
etc., — Whenever, Now, — All or Everi/, Some, This, etc. The commonness
and notoriety of this subordination is the cause why it has not been signalized ;
and if signalized, and overtly expressed, Hypotheticals might be turned into
Categoricals. It is better, however, to leave them as immediate inferences.
For it would be found awkward and round-about to oppose, for example, the
Possible to the Actual, as determining a difference of terms. (See Molinaeus,
Elem. Log., L. i. tr. iii. p. 95, and Pacius, In Org., De Sgll. Hyp., p. 533.) The
example of the Cadaver ther6 given shows the approximation to the ordinary
Hypotheticals. They may stand, in fact, either for Categoricals or Hypotheti-
cals.
8.) Disjunctives — (Possibly) A is either B or non-B ; .•. (Actually) A is
either, etc.
9 ) The doctrine in regard to the Universal Quantity, and the Affirmative
Quality (see Krug, LogiL; §§ 57, 83, 86, pp. 171, 264, 275), of the supposition,
proposition, of Conjunctive (?) and Disjunctive Hypotheticals, is solved by my
theory of Possibility. In it is virtually said (whatever quantity and quality be
the clauses), — " on any possible supposition." (On the Quality, v. Krug, Logik,
§ 57, p. 172. Pacius, In Org., p. 533. Molinajus, Elem. Log., I. c.)
10.) Possibly, — problematically includes as species the actual affirmative and
the actual negative. It will thus be superfluous to enounce a negative in op-
position to an affirmative alternative ; for thus the possible would be brought
down to the actual, and the whole syllogism be mere tautological repetition.
11.) The quantified terms, if introduced, must either be made determinate,
to suit the Hypotheticals, or must ruin their inference. For example — If all
APPENDIX. 611
or some man he some animal, we must be able to say, Bicf some animal is not,
therefore 7nan (any or some) is not. But here some animal, except definitized
into the same some animal, would not warrant the required inference. And so
in regard to other quantifications, which the logicians have found it necessary
to annul.
12.) The minor proposition may be either categorical or hypothetical. (See
Krug, Lo(jik, § 83, p. 264. Heerebord, Instil. Logicar. Synopsis, L. ii. c. 12, pp.
266, 267.) In my way of stating it: — If man is, animal is, .^ If man is (or
mati being), animal is.
13.) Of notions in the relation of sub-and-superordination (as, in opposite
ways Depth and Breadth,. Containing and Contained), absolutely and relatively,
the lower being affirmed, the higher are (partially) affirmed; and the higher
being (totally) denied, the lower are (totally) denied. A, E, I, O, U, Y may
represent the descending series.
The first proposition is conditional, complex, and alternative ; we should
expect that the second should be so likewise. But this is only satisfied on my
plan ; whereas, in the common, there is a second and a third, each categorical,
simple, and determinate.
The subaltern ation is frequently double, or even triple, to wit, 1°, From the
Possible to the Actual. 2° (for example). From Everyichere to here, or this
place, or the place by name. 3°, From all to some, etc. — in fact, this infer-
ence meny be of various kinds.
The lueraATjif/is of Aristotle may mean the determination, — the subalterna-
tion ; the Kara TroiSr-nTa may refer to the specification of a particular quality or
proportion under the generic ; and the irp<5<7A.7ji|/« of Theophrastus (for tlw
reading in Aristotle should be corrected) may correspond to the kuto, ■jroi6T7]ra.
There is no necessary connection, formally considered, between the antece-
dent and consequent notions of the Hypothetical major. There is, conse-
quently, no possibility of an abstract notation ; their dependence is merely
supposed, if not material. Hence the logical rule, — Propositio conditlonalis
nihil ponit in esse. (See Krug, Logil; § 57, p. 166.) But on the formal sup-
position,— on the case thought, yvhat are the rules ?
We should distinguish in Hypotheticals between a propositional antecedent
and consequent, and a syllogistic A and C ; and each of the latter is one
proposition, containing an A and C.
The antecedent in an inference should be that which enables us formally to
draw the conclusion. Show in Categoricals and in Immediate Inferences. On
this principle, the conclusion in a Hypothetical will contain what is commonly
called the minor proposition with the conclusion proper ; but it will not be one
and determinate, but alternative.
If there were no alternation, the inference would follow immediately from
the fundamental proposition ; and there being an alternative only makes the
conclusion alternatively double, but does not make a mediate inference.
il2 APPENDIX.
To make one alternative determinate is extralogical ; for it is true only as
■aaterially proved. 1°, The splitting, therefore, of the conclusive proposition
iato two — a minor and a conclusion proper — is wholly material and extralogi-
cal ; so also, 2°, Is the multiplying of one reasoning into two, and the dividing
between them of the alternative conclusion.
Errors of logicians, touching Hypothetical and Disjunctive Reasonings :
1°, That [they] did [not] see they were mere immediate inferences. ^
2°, Most moderns that both Hypothetical.
S®, That both alternative reasonings in one syllogism.
4", Mistook a part of the alternative conclusion for a minor premise.
5°, Made this a distinct part (minor premise), by introducing material conad-
erations into a theory of form.
6°, Did not see what was the nature of the immediate inference in botb, —
how they resembled and how they differed.
n. — Historical Notices.
(COWJXmCTIVE AND DISJDJJCTIVE.)
(a> ARISTOTLK.
(August 1852.)
Aristotle (Anal. Pr. L. i. c. 32, § 5, p. 262, Pacii) describes the process of the
Hypothetic Syllogism (that called by Alexander 8i' oA«i/), but denies it to be a
syllogism. Therefore his syllogisms from Hypothesis are something different.
This has not been noticed by Mansel, Waitz,
Thus literally: — " Again, if 7nan existing, it be necessary that animal exist,
and if animal, that substance : man existing, it is necessary that substance exist
As. yet, there is, however, no syll(^istic process ; for the propositions «Jo not
stand in the relation we have stated. But, in such like cases, we are deceived,
by reason of the necessity of something resulting from what has been laid
down ; whilst, at the same time, the syllogism is of things necessary. But the
Necessary is more extensive than the Syllogism; for though all syllogism be
indeed necessary, all necessary is not syllogism." Why not? 1**, No middle.
i°. No quality, — affirmation or negation ; problem, also not assertory, — hypo-
thetical not syllogistic. 3°, No quantity. Compare, also. An. Pr. L. i. c. 24.
Aristotle (Anal. Post., L. i. c. 2, § 15, p. 418; c. 10, §§ 8, 9, p. 438) maker,
T/icsh or Position the genus opposed to Axiom, and containing under it, as
spcL-ies, 1°, Hifpothesis or Supposition ; and, 2°, Definition. Hyjwthesis is that
thesis which assumes one or other alternative of a contradiction. Definition is
that thesis which neither affirms nor denies. Hypothetical, in Aristotle's sense,
is thus that which affirms or denies one alternative or other, — which is not
indifferent to yes or no, — which is not possibly either, and, consequeutlx»
APPENDIX. 618
iBckides both. Hypotheticals, as involving a positive and negative aUemative,
are thus, in Aristotle's sense, rightly named, if divided; but, in Aristotle's
sense, as complete, they are neither propositions nor syllogisms, as not affirmiiKg
one alternative to the exclusion of the otfaer.^
(b) AUUOmUS HERSaM.
I. Ammonias Hermiae, on Aristotle Of Enouncement, Introduction, f 3, ed.
Aid. 1546, f. 1. ed. Aid. 1503. After distinguishing the five species of Speech,
according to the Peripatetics, — the Vocative, the Imperative, the InteiTogative,
the Optative, and the Enunciative or Assertive, — having further stated the
corresponding division by the Stoics, and having finally shown that Aristotle,
in tliis book, limited the discussion to the last kind, that alone being recipient
of truth and falsehood, he thus proceeds: — " Again, of Assertive speech (oiro-
4i«i/T<>for> \6yov), there are two species ; the one called Categoric [or Predicative},
the other Hypothetic [or Suppositive}. The Categoric denotes that something
does or does not belong to something : as when we say, Socrates is icalking, Soc-
rates is tiot walking ; for we predicate walking of Socrates, sometimes affirm-
atively, sometimes negatively. The Hypothetic denotes that something being,
something [else] is or is not, or something not being, something [else] is not or is :
As when we say, If man he, animal also is, — If he he man, he is not stone, — ■
If it be not day, it is night, — If it be not day, the sun has not risen.
" The Categoric is the only species of Assertive speech treated of by Aris-
totle as that alone perfect in itself, and of utility in demonstration ; whereas
Hypothetic syllogisms, usurping [usually] without demonstration the [minorj
proposition, called the 2'ransumplion, or Asstanplion, and sometimes even a
[major premise] Conjunctive or Disjunctive, requiring proof, draw their per-
suasion from hypotheses, should any one [I read il res for ^ns] concede their
primary suppositions. If, then, to the establishment of such suppositions we
should employ a second hypothetic syllogism, — in that case, we should require
a further establishment for confirmation of the suppositions involved in it ; for
this third a fourth would again be necessary; and so on to infinity, should we
attempt by hypotheses to confirm hypotheses. But to render the demonstra-
tion complete and final, it is manifest that there is needed a categoric syllogisnj
to prove the point in question, without any foregone supposition. Hence it is
that Categoric [reasonings] are styled Syllogisms absolutely; whereas Hypo-
tlictic [reasonings] of every kind are always denominated Syllogisms from
hypothesis, and never Syllogisms simply. Add to this, that Hypothetic enounce-
1 [Whether the SpUoghms ex hypothesi of Opera Logiea Tract. Si/U. P. iv. c. x. tit. 2, p.
■Aristotle are correspondeut to the ordinary 548. Bursgersdicius, Instit. Log. L. ii. cc. 13,
Hypothetical Syllogism. 14, pp. 263, 270, 275. Ritter, Gesh. der PhU.
Fop the affirmative, see Pacins, Com. In iii. p. 96. (Eng. Tr., p. 80.) Ramus, Sehol»
Org. An. Prior, L. i. cc. 28, 29, 44, pp. 153, 177, Dial. L. vii. CC. 12, 13, pp. 492, 503. Molinaeus,
194. St. Hilaire, Translation of Organon, vol. EUmenta Logiea, p. 95 et seq. Waitz, Org. i.
ii pp. 107, 139, 178. pp. 427, 433. Of. Alexander, In An. Prior, If.
For the negative, see Piccartus, In Org. An. 88, 109. Philoponus, la An. Prior, ff, 60», 60*,
Prior, L. i. cc. 40, 41, 42, p. 500. Neldelius, 87^, 88. Anonymus, De Syllogismo, f. 4#.
De Usu Org. Arist. P. iiL c. 2, pp. 38, 45 (1607). Magentinus, In An. Prior, f. 17*. Ammonias,
Keckermann, Qp<t«, pp. 766,767. Selieibler, In de Interp.,2^. Blemmidas, .^rat. Xof . c. flS.]
614 APPENDIX.
ments are made up of Categoric. For they express the consetjuence or oppo-
sition (o/coA.oM^ioj' fi iidarcurif) of One Categoric proposition and another, uniting
them with each other by either the Conjunctive or Disjunctive particle (avft-
irKeKTiK^ fl Sia^evKriK^ &vvS4(t/jlw) , in order to show that they constitute together a
single enouncement. For these reasons, therefore, Aristotle has only consid •
ered, in detail, the Categoric species of Assertive speech."
(c; ANomruovs scholios}
In Hypothetic Syllogisms, the first [I] are those of two terms [a]), Conjunc-
tive, or [b] Disjunctive (opoi ol awrifinfuoi i) SiaKekufitvoi) ; then follow [11] the
two [classes of] syllogisms with three, and these conjunctive terms.
[I. a.] " There are four syllogisms through the Return (^ ^xcw'oSos) on tlie
prior (i wp6repos, 6 irpcoros') [or antecedent clause of the hypothetical proposi-
tion], and four through it on the posterior (6 Seurepoi, 6 ^^x*'''''*)- For the
terms are taken either both affirmatively or both negatively. And the return
upon the prior is ponent (jcari Afaiv'), upon the posterior tollent (kot^ aycuptffw').
For example [the return upon the prior] :
(1.) 7/ A.is,B is; (Return) but A i«; (Conclusion, av/iwtpairfta) Aere/ore, B is.
(2.) J/ A is, B is not ; bvt Ais; therefore, B is not.
(3.) If Ais not. Bis; bvt A is not; therefore, B is.
(4.) If X is not, B is not : but Aisnot; therefore, B is not. ■
" The return upon the posterior:
(1.) If A is, B is ; butB is not ; therefore, A is not.
(2.) If A is, B is not ; but B is ; therefore, A is not.
(3.) If Ais not, B is ; but B is not ; therefore, A is.
(4. ) If A is not, B is not ; btU B is ; therefore, A too it.
[b.] " Following those of conjunctive, are syllogisms of disjunctive terms.
In these, the return is upon either [clause] indifferently. For example : If it
must be that either A is or B ix [in the one case]; B is not, therefore, A is ; or
[in the other], A is not, therefore B is.
[II.] " Of three conjunctive terms, there are [in the figures taken together]
eight syllogisms, through a return on the prior, and eight [sixteen]* through a
return on the posterior [clause]. For the three terms are correlated {vwri^fit-
Tou), either all affirmatively, or some ; and here either the third alone, or the
third and second, or the second alone, negatively. Again, either all are neg-
atively correlated, or some ; and here the third alone, or the third and second,
or the second alone, affirmatively. In this manner the correlation [in each
I In Waftz, Org", i. pp. 9, 10. premise (the minor placed first, according to
» It would seem that the author here, and the common practice of the Greeks, or the
in the last sentence, discount? altogether the major prior, in Aristotelic theory) he should
first figure, puzzled, apparently, to which accord the designation of first.
APPENDIX. 615
figure] is eightfold ; taking for exemplification only a single mood [in the
several figures] :
If A is, B is ;
If B is, C is ;
If A is, therefore, C is.
This is of the first figure. For the middle collative term (6 ffwdywv ipos fifaos)
is twice taken, being the consequent (6 xirywv) in the former conjunctive
[premise] (t^ Trp6repov avvmnfjLiuov) , the antecedent (6 riyov/xevos) in the latter.
Wherefore, these syllogisms are indemonstrable/ not requiring reduction
{t] avdxvffis) for demonstration. The other moods of the first figure are, as has
been said, similarly circumstanced.
" The second figure is that in which the collative term [or middle] {6 awiyuv)
holds the same relation to each of the collated [or extreme] terms, inasmuch as
it stands the antecedent of both the conjunctive [premises], except that in the
one it is affirmative, in the other negative. Wherefore, when reduced to the
first figure, they demonstrate, as is seen, through the instance of a single mood
composed of affirmative collated terms. As —
If A is, B is ;
If A is not, C is ;
If B is not, tha'efore, C is.
" This is reduced to the first figure in the following manner : — Whether it
has the collated terms, both affirmative, or both negative, or both dissimilar to
the reciprocally placed collative term, there is taken m the reduction the
opposite [and converse] of the prior conjunctive [premise] ; and the latter is
applied, in order that the opposite of the consequent in the former conjunctive
[premise] may find a place in the foresaid mood. As —
If B is not, A is not;
If A is not, C is ;
If B is not, therefore, C is.
" This it behooved to show.
*' The third figure is that in which the collative term holds the same relation
to each of the collated terms, being the consequent in either conjunctive [pre-
mise] affirmatively and negatively, as in the example of a single mood again
consisting of aflfirmative collated terms. Thus :
If A is, B is ;
» If C is, B is not ;
If A is, therefore, C is not.
" The reduction of this to the first figure is thus effected. The opposite [a
1 Vide Apuleius. [De Dogm. Plat. iii. p. 37. Elm. Cf. Discussions, p. 836. — Ed.]
616
APPENDIX.
converse E] of the second conjunctive [premise] is taken along with tl»e
first conjunctive [premise], and the antecedent of the former is apf^ied to iSw
opposite of the latter's consequent ; as in the foresaid mood. Thus :
I
I IfAis,B{s;
If B is, C IS tiot;
If A is, therefore, C is tut.
** All this requires to be shown concretely. As in the first figure £fint
mood]:
If day is, light is ;
If light is, visible objects are seen ;
If day is, therefore, visible otijeeis are seen.
*• Second figure, first mood :
If day is, light is;
If day is not, the sun is under the earth ;
If light is not, the sun is [therefore] under ike earth. .
" Reduction :
If light is not, day ui not ;
If day is not, the sun is under the earth ;
If light, therefore, is not, the sun is under the earth,
•• Third figure, first mood :
If day is, light is ;
If things visible are unseen, light is not;
If day, therefore, is, things visible are not unseen.
'• There are eight moods of the second figure, and eight of the third ; two
composed of athrmativcs, two of negatives, four of dissimilars, with a similar
or dissimilar coUative.
** End of Aristotle's Analytics."
Relative to the translation from the Greek interpolator on Hypothetical
Syllogisms, in Waitz (Org. i. p. 9, 10); and in particular to the beginning
of [II].
Better thus : — In all the Figures : — the quality of the syllogism is either
Pure, — and here two, viz., ooe affirmative and one n^ative ; or Alixedf —
and here six, viz., three in which affirmation, and three in which negation, has
the preponderance.
APPENDIX.
The ibllowing are thus arranged :
617
First Figure.
A]l Jf A is, B is ;
A If B it, C is;
.: J/Ais, Cis.
Second Figure.
^ B is, A is ;
If Bis, Cis;
.'. Jf A is, C is.
Third Figure.
J/Ais, B is;
Jf G is, Bis;
.*. Jf A is, Cis.
1,2, Jf A is, B is ;
B Jf Bis, Cis not;
.'. J/Ais,Cisnot.
Jf B is, A is ;
Jf B IS, C is not ;
.'. Jf A is, C ie not.
If A is, B is;
Jf C is not, B is ;
.'. If A is, C is noL
1,3, Jf A is, B isnot ;
C If B is not, C is ;
.-. If A is, Cis.
2, 3, If A is not, B is ;
D If Bis, Cis;
.'. If A isnot, C is.
If B is not, A is;
If B is not, C is ;
.'. If A is, C is.
If B is, A is not ;
If B is, C is ;
.'. If A is not, C is.
If A is, B is not ;
If C is, B is not ;
.'. If A is, C is.
If A is not, B is;
Jf C is, B is ;
.'. If A is not, C i
All If A is not, B is not.
ElfBis not, C isnot ;
.'. If A is not, C is not.
//TO is not, A is not ;
If Bis notj C is not ;
.'. If B is not, C is not.
If A is not, B is not ;
If C is not, B is not ;
.'. If A is not, C is not.
a. M
1, 2, If A is not, B is not ;
F If Bis not, Cis;
.'. If A is not, C is.
If B is not, A is not ;
If B is not, C is ;
.'. If A is not, C is.
1,3, Jf A is not, B is ; If B is, A is not ;
G IfB is, C is not ; If B is, C is not ;
.'. If A is not, C is not. .•. If A is not, C is not.
If A is not, B is not ;
If C is, B is not ;
.'. If A is not, C is.
If A is not, B is ;
If C is not, B is ;
.•. If A is not, C is not.
2, 3, JfA is, B isnot;
H IfBis not, C is not ;
,'. If Ais,C is not.
If B is not, A is ;
If B is not, C is not ;
.'. If A is, C is not.
If A is, B is not ;
If C is not, B is not ;
.•. If A is, C is not.
These eight syllogisms are all affirmative, the negation not being attached
to the principal copula.^ If, therefore, the negation be attached to one or
other premise, there will be sixteen negative syllogisms, in all twenty-four.
The negatives are, however, awkward and useless. (See Lovanienses, p. 3t)l.)
But each of these twenty-four syllogisms can receive twelve different forms
of predesignation, corresponding to the twelve moods of the simple categorical ;
accoi'diiig to which they are arranged and numbered. It is hardly necessary
1 See Lovanienses, In Arist. Dial., Tract, de Hj/potheticis Syllogisinis, p. 299.
78
618
APPENDIX.
to notice that the order of the premises is in comprehension, after the Greek
fashion of the scholiast.
r A
MB
c c
i.
ii.
»
iii.
1
iv.
V.
vi.
• »
TU.
1 •
1
Tiii.
ix.
>
X.
>
xi.
»
>
xU.
>
• »
>
This is exemplified in the Syllogism E of the preceding table, thus :
1. If all K is not, all B is not; if all B is not, all C is not; .-. if all A is not, aH
B is not.
2. If some A is not, all B is not; if all B is not, some C is not; .'. if some A is not,
some C is not.
3. If some A is not, all B is not ; if all B is not, all C is not ; .'. if some A is not,
all C is not.
A. If all A is not, all B is not ; if all B is not, some C is not; .'. if aU A is not, some
C is not ;
5. If all A is not, some "Qis not; if all BJs not, all C is not ; .'. if all A is not, all C
is not.
6. If some A is not, all 'D is not ; if some B is not, aUCisnot; .'. if some A is not,
all C is not.
1. If aU A is not, some B is not ; if all B is not, some C is not ; .'. ifaUA is not, some
C is not.
8. If some A is not, aU B is iiot ; if some B is not, all C is not; .'. if some A is not,
all C is not.
9. If some A is not, some B is not ; if all B is not, all C is not; .'. if some A is not,
all C is not.
10. If all A is not, all B is not ; if some B is not, some C is not; .'. if all A is not,
some C IS not.
11. If some A is not, some B is not ; if all B is not, some C is not; .'. if some A is not,
sonte C is not.
12. ^ some A is not, all B is not ; if sotne B is not, someC is not; .*. \f some A is not,
some C is not.
APPENDIX. 619
IX.
SORITES.
(Sec p. 274.)
(Without order.)
All logicians have overlooked the Sorites of Second and Third Figures.
In Sorites of the; Second or Third Figures, every term forms a syllogism
with eveiy other, through the one niiddh' term. In Sorites of the First Figure,
every Second term at most forms a syllogism "witli everv other, through its
relati\e middle term.
No subordination in Sorites of Second or Third Figure, i lyjo no one domi-
nant coiK-hision.
Alias — In First Figu'-e. tiiere being a suboi-dination of notions, there may
be a Sorites with diifcvi'iit middles (all. however, in a conmion dependency).
In Second and Tliird Figu'vs. then' being no sul)ordination of terms, tlie only
Sorites compettMit is that by repetition of the same middle. In First Figure
thei'e is a new middle term for every new progress of the Sorites; in Se(;ond
and Tliii'd, oidy one nfiddle term for an\" nimiber ot' extremes.
In I'ii-st Figure', a Ssllogisni only between evi?ry second term of the Sorites,
the intermediate term constituting the middle term. In the others, everv two
propositions of the I'ommon middle term Ibrm a s_\ llogism.
Alias — Thert' being no subordination in Second and Tliird Figures between
the extremes, there, consecpiently, arc —
l'^. No relations between extremes, except through the middle term.
'l"^. Tliere is only one possible middle term ; any number of othei's.
.'!°. Ever}- two of the terms, with the middle term, may form a syllogism.
4^, 2s'o order.
Before concluding this subject, I would correct and amplify the doctrine in
regani to the Sorites.^
1°, I would state that, by the quantification of the Predicate (of which we
are hereafter to treat, in reference to reasoning in general), there are two
kinds of Sorites ; the one descending from whole to part, — or ascending from
part to whole ; the other proceeding from whole to whole : of wdiich last it is
now alone requisite to speak. It is manifest, that if we can find two notions
wholly equal to a third notion, these notions will be wholly equal to each other.
Thus, if all trilateral figure be identical with all triangular figure, and all tri-
angular figure with all figure the sum of whose internal angles is equal to two
right angles, then all figure, the sum of whose internal angles is equal to two
right angles, and all trilateral figure, will also be identical, reciprocating, or
absolutely convertible. We have thus a simple syllogism of absolute equation.
On the same principle, if A and B. B and C, C and I), are absolutely equiva-
lent, so also will be A and D- We may thus, in like manner, it is evident,
1 IiiteriioIaliiJ-.i in Lertitres. See p. 27-1. — tu.
mQ
APPENDIX,
have a Sorites of absolute equivalents. It is not, indeed, very easy always to
find four or more terms or notions thus simply convertible. In geometry, we
maj' carry out the concrete syllogism just stated, by adding the three following
propositions : — All fgure, the sum of whose internal angles is equal to two right
angles, is all figure which can he bisected through only one angle ; — All figure
which can be bisected through only one angle, is all figure which, bisected through
an angle and a side, gives two triangles ; and All figure tvhich, thus bisected,
gives two triangles, is all figure which, bisected through two sides, gives a triangle
and a quadrangle ; and so forth. In theology, perhaps, however, these series are
more frequently to be found than in the other sciences. The following; twelve
equivalent concepts constitute at once a good example of such a Sorites, and
at the same time exhibit a c(Mnpendiou3 view of the whole Galvinistic doctrine.
These are,— 1, Elected; 2. Redeemed; 3. Called; 4. Graced with true repent-
ance; 5. With true faith ; 6. With true personal assurance; 7. Pardoned; 8.
Justified; 9. Sanctified; 10. Endotced with perseverance; 11. Saved; 12. Glorified.
This series could indeed be amplified ; but I have purposely restricted it to
twelve. Now, as All the elect are all the redeemed, all the redeemed all the called,
all the called all the [^truly"] penitent, all the [/ru/y] penitent all the [^Iruly"] believ-
ing, all the [_(ruly2 believing all the [/rz/Zy] assured, all the \truly'\iassured all the
pardoned, all the pardoned all the justified, all the justified all the sanctified, all
the sanctified all the perseverant, all the perseverant all the saved, all the saved
all the glorified, all the glorified all the blest with life eternal; it follows, of neces-
sity, that all the blest with life eternal are all the elect. To turn this affiraaative
into anegaiivc Sorites, we have only to say, either at the beginning, — None
of the reprobate are any of the elect, an<l, consetjuently, infer, at the end, that
none of tfie blessed with eternal life are any of the reprobate ; or, at the end, —
None of the hhM icith eternal life are any of the punished, and, consequently,
infer that none of the punished are any of the elect. Perhaps the best
formula lor tiii^s kind of Sorites is to be found in the letters a, b, c. This will
afford us a Sorites of six terms, viz., a, b, c — a, b — b, a, c — b, c, a — c, a, b — c,
b, a, — which are all virtually identical in their contents. If there be required
a formula for a longer- Sorites, we may take the letters a, b, c, d, which will
afford us twenty-four terms. Perhaps the best formula for a descending or
ascending Sorites is, for example, a, b, c, d, e, f— a, b, c, d, e, — a, b, c, d, — a,
b, c, — a, b, — a.
J. COMPRKHENSIVK SOKITES — PKOORESSITE AKD BEGRESSITE.
E
I.acephalus
APPENDIX.
921
II. — EXTENMVB SORITES.
: B, ■ : C , ■ : D ,
: E
X.
SYLLOGISM.
L — Its Enouncement — Analytic and Synthetic — Order of Premises.
(See p. 281.)
(a) BIfOV!TCEMENT OF SYLLOGISM.
(Nov. 1848.) — There are two orders of enouncing the Syllogism, both
natural, and the neglect of these, added to the not taking into account tlic
Problem, or Question, has been the ground why the doctrine of syllogism has
been attacked as involving a petitio principii, or as a mere tautology. Thus,
Buffier cites the definition the art of confessing in the conclusion what has been
already avowed in the premises} This objection has never been put down.
The foundation of all syllogism is the Problem. But this may be answered
either Analytically or Synthetically.
L Analytically (which has been wholly overlooked) thus, — Problem or
quaesitum. Is T C ? Answer, P is C ; for P is M, and M is C. This is the
reasoning of Depth. More explicitly : — Does P contain in it C^ T contains
in it C ; for T contains in it M, and M contains in it C. But it is wholly indif-
ferent whether we cast it in the reasoning of Breadth. For example : — Does
C contain under itT? C contains under it P; for C contains under it M, and
M contains under it T?
Here all is natural ; and there is no hitch, no transition, in the order of pro-
gressive statement. The wliole reasoning forms an organic unity : all the parts
of it being present tO' the mind at once, there is no before and no after. But it
is the condition of a verbal enouncement, that one part should precede and
follow another. Here, accordingly, the proposition in which the reasoning is
absolved or realized, and which, from the ordinary mode of enouncement, has
1 Seconde Logique, Art. iii. § 126. — Ed. {that good mm so think), lastly the major [tlial
2 Plato, in a letter to Dionysius (Epist.2), the presentiments of divine men are of highest
reverses the common order cf Syllogism, authority). Platonis Of/era, Bekker, ix. p. 74.
placing the conclusion first {that he thinks Cf. Melanchthon, Dinlectica, L. iii., De Fig-
there is some stnse in the dead)) then the minor uratione, p. 93, ed 1542.
622 > APPENDIX.
been styled the Conclusion, is stated first ; and the grounds or reasons on which
it rests, which, from the same circumstance, ha\e been called the Premue or
Antecedent, are stated last. This order is Analytic. We proceed from the
effect to the cause, — from the principiatum to the principia. And it is evident
that this may be done indifferently either in Depth or Breadth ; the only dif-
ference being that in the counter quantities the grounds or premises naturally
change their order.
II. Synthetically, — the only order contemplated by the logicians as natural,
but on erroneous grounds. On the contrary, if one order is to be accounted
natural at the expense of the other, it is not that which has thus been exclu-
sively considered. For — '
1°, It is full of hitches. There is one great hitch in the separation of the
conclusion from the question ; though this latter is merely the former proposi-
tion in an assertive, instead of an interrogative, form. There is also at least
one subordinate hitch in the evolution of the reasoning.
2°, The exclusive consideration of this form has been the cause or the occa-
sion of much misconception, idle disputation, and groundless objection.
(On the two Methods ; tumultuary observations, to be better arranged, and
corrected.)
1°, In the first or analytic order, what is principal in reality and in interest
is placed first, that is, the Answer or Assertion, called on the other order the
Conclusion.
2°, In this order all is natural ; there is no hitch, no saltus, no abrupt transi-
tion ; all slides smoothly from first to last.
a) The question slides into its answer, interrogation demands and receives
assertion.
b) Assertion requires a reason, and prepares us to expect it; and this is
given immediately in what, from the other order, has been called the Antecedent
or Premises.
c) Then the first term, either in Breadth or Depth, is taken first in the
ground or reason, and compared with M; then M is compared with the other.
As in Breadth : — Does C contain under t7 F ? C contains T ; for C contains
under it M, and M contains under it T. In Depth — Does T contain in it C ?
r contains in it C ; for T contains in it M, and M contains in it C. This is the
first Figure. Second Fijiurc, usinjj common lanjjuase: — Is F C? F is C
(and C is F) ; for F and C are both the same M. Here the two extremes taken
together are compared with M. In the third Figure M is compared with both
extremes — /sFC? T is C (and M is F) ; for the same M w both F and C.
8", In this order there is nothing pleonastic, nothing anticipated.
4°, Nothing begged.
5°, In this method the process is simple. Thought is one ; but to be enounced
it must be analyzed into a many. This order gives that necessary analj-sis,
and nothing more.
6°, In this order, wlu'u assertive, answer is limited by question ; goo<l reason
why, in S^'cniul and Third Figures, one answer should be given.
7°, Tliis order i.s the one generally used by the mathematicians. (See Twea-
ten, Logik, insltcsondere die Analytik^ § 117, p. 105, and below, p. 626. Plato
also).
APPENDIX. 623
8°, If the Quaesitum be stated as It ought to be, this order follows of course;
and the neglect of the quaesitum has followed from the prevalence of the other.
If the quaesitum be stated in using the common form, we must almost of course
interpolate a yes or a no before proceeding to the premises in the common
method ; and in that case, the conclusion is only a superfluous recapitulation.
In the Synthetic, or common order, all is contrary. (The numbers cor-
respond.)
1°, In this order, what is first in reality and interest, and in and for the sake
of which the whole reasoning exists, comes last ; till the conclusion is given we
know not (at least we ought not to know) how the question is answered.
2°, In this order all is unnatural and contorted by hitches and abrupt transi-
tions, There is no connection between the question and what prepares the
answer, — the premise. (Show in detail.)
3°, In this order all is pleonastic and anticipative. The premises slated, we
already know the conclusion. This, indeed, in books of Logic, is virtually
admitted, — the conclusion being commonly expressed by a therefore, etc. An-
cient doctrine of Enthymeme (Ulpian, etc.), unknown to our modern logicians;
among their other blunders on the Enthymeme. On the common doctrine,
iLogic — Syllogistic — is too truly defined the art of confessing in the conclusion
Avhat had been already avowed in the premises.
4"^, On this order the objection of petido principii stands hitherto unrefuted, if
not unrefutable, against Logic'
6°, In this order the process is complex. The simple thought is first mentally
analyzed, if it proceed, as it ought, from the quaesitum; but this analysis is not
expressed. Then the elements are recomposed, and this recomposition affords
the synthetic announcement of the syllogism, — the syllogism being thus the
superfluous regress of a foregone analysis. Aristotle's analytic is thus truly
a synthetic ; it overtly reconstructs the elements which had been attained by a
covert analysis.^
G°, In this method, the problem hanging loose from the syllogism, and, in
fact, being usually neglected, it does not determine in the Second and Third
Figures one of the two alternative conclusions which, ex facie syllogismi, are
competent in them. The premises only being, there is no reason why one of
the conclusions should be drawn to the preference of the other. Mem. Coun-
ter-practice old and new. The logicians ought not, however, to have ignored
this double conclusion.
7°, See corresponding number.
8°, See corresponding number.'
1 [?,{eyc&Tt(Elemenis, vol. ii. cli. 3, § 2, Works, meaning of the term is the doctrine showing
vol. iii. p. 202, et alibi) makes this objection, how to analyze or reduce reasonings to syl-
Refuted by Galluppi, Li?z. di Logica e di Meta- logisms; syllogisms to figure; figure to mood;
/isicn, Lez. i. p. 242, f( seq.] second and third figures to first; syllogisms
2 [Aristotle's Anali/tics are in synthetic or- to propositions and terms; propositions to
der; they proceed from the simple to the terms; for of all these analysis is said. See
compound; the elements they commence' Pacci Organon, An. Prior, i. cc. 2, 32, 42, 44,
with are gained by a foregone analysis, which 45, pp. 128, 261, 273, 275, 278, 280.]
is not expressed. They are as synthetic as a
grammar commencing with the letters. The 3 Compare Discussions, p. 652. — Ed.
624 ArrKNDix,
(b) ORDER OF PREMISES.
Aristotle places the middle term in the first Figure between the extremes^
and the major extreme first ; — iu the second Figure before the extremes, an'!
the major extreme next to it ; — in the third Figure, after the extremes, and
the minor extreme next to it.
In his mode of enouncement this relative order is naturally kept ; for he
expresses the predicate first and the subject last, thus : A is in oi/ B, or A u
predicated of all B, instead of saying All B is A.
But when logicians came to enounce propositions and syllogisms in conform-
ity to common language, the subject being usually first, they had one or other
of two difficulties to encounter, and submit tliey must to either ; for they must
either displace the middle term from its intertoediate position in the first Figure,
to say nothing of reversing its order in the second and third ; or, if they kept
it in an intermediate position in the first Figure (in the second and third the
Aristotelic order could not be kept), it behooved them to enounce the minor
premise first.
And this alternative actually determined two opposite procedures, — a dif-
ference which, though generally distinguishing the logicians of different ages
and countries into two great classes, has been wholly overlooked. All, it must
be borne in mind, regard the syllogism in Figure exclusively, and as figured
only in Extension.
The former difficulty and its avoidance determined the older order of
enouncement, that is, constrained logicians to state the minor premise first in
the first Figure ; and, to avoid the discrepancy, they of course did the same for
uniformity in the second and third. Such is tlie order.
The latter difficulty and its avoidance determined the more modem order of
enouncement, that is, constrained logicians to surrender the position of tlie
middle term as middle, in following the order of the major premise first in all
the Figures.
Philoponus on the First Book of the Prior Analytics, c. iv. § 4 (Pacian
Division), f. xx. ed. Trincavelli. — " This definition appears to be of the extremes
and of the middle term ; but is not. It behooves, in addition, to interpolate in
thought an ^onli/;' and thus will it be rightly enounced, as if he had said: —
But the extremes are both that which is only in another, and that in which another
only is. For if A is [predicated] of all B, and B is [predicated] of all C, it is
necessary that A should be predicated of all C. This is the first syllogistic
mood. Two universal affirmatives, inferring a universal conclusion. For if
B is in all C, consequently C is a part of B ; but again B is a part of A ; con-
sequently, A is in all C, inasmuch as C is a part of B. But what is here said
will appear more clearly from a concrete example — Substance of all animal:
(inimal of all man; (there follows) substance of all man. And backwards
(avanaMv^, All man animal; all animxd substance ; all man therefore substance.
In regard to this figure, it is plain how we ought to take the terms of the first
mood. The first [major] is most generic ; the second [middle] is a subal-
tern genus; and the third [minor] is a species more special than the middle.
But a conclusion is here always necessary. Thus, following the synthetic
order, that is, if we start from the major term, substance begins, beginning also
APPENDIX
62{
tlie conclusion. Substance of all animal (^substance stands first); animal of all
man ; (finally the conclusion commences with substance) — substance 0/ all man.
But if [on tlic analytic order] we depart from the minor term, as from man, in
this case the conclusion will, in like manner, begin therewith : All man animal ;
all animal substance ; all man substance."
This is the only philosophic view of the matter. His syllogisms really ana-
lytic ( = In Depth).
Analytic and Synthetic ambiguous. Better, — order oi Breadth and Depth.^
1 [Instances and authorities for the enounce-
ment of Syllogism, with the Minor Premise
stilted first:
Ancients.
Gr^'eks: — Gregory of Xyss-a, Optra, t. ii. p.
612, in liis 12 (not 10) Syllogisms against Slan-
ieheans, varies. These very corrupt. Joan-
nes Damasceniis (Diaieci/ca, c. G4, Opera, ed.
Lequien, Paris, 1712, t. i. pp. 65, 66) gives two
Syllogisms, one with minor first. Alcinous,
De Doct. Plat. L. i. CC. 5 and 6. Aristotle
often places minor first. See ZabareIla,0/icm
Lo^ica. De Qiiarta Figvra, p. 124 Vallius,
Logica, t. ii , pp. 72, 76. Aristotle and Alex-
ander not regular in stating major proposi-
tions. See in First Figure, An. Pr. i. c. 4.
Aristotle used the " whole ■' only of the predi-
cate. See Zabaiella, Tabula-. In An. Prior, p.
149. (But see above, p. 548.) Boetliius,Opfm,
pp. 502. 5S3 Aiistotle, An Pr. i. c. \,suijfine,
ubi Alexander, f. 9 a. Philoponus, f. 17 a. f 11
b. Alexander Aph. In An. Pr. i. IT. 9 a, 15 b.
I'hiloponus, In An. Pr. i. flf. 11 b, 20 a, explains
tlie practice of Greek Peripatetics in this
matter. See also if. 17 a, 18 a; and 11, 21 a
— these in i Fig. — in ii. Fig. 23 b. The same
In Phystca, i. c 1, f. 2. Tliomistius, In An.
Po.tt. ii. c. 4. Anonymus, De Syllogismo, f.
43 a. Gregorius Ancponymus, Coiw/ienrf. Ph.il-
oiophim St/ntagmn, L. V cc. 1, 6, pp. 58, 70.
Georgius Diaconus Pachymerius, Epit. Log.
tit. iv. cc. 1 — 4. Sextus Empiricus, Pyrrh. Hy-
potypos., L. ii. cc. 13, 14, pp. 103, 110. Clemens
Alex. Strom. L. viii. Opera, p. 784 (ed. Syl-
burgii). liieraniidas, E/iitome Logica, c. 31, p.
219. Gregorius Trapezuntius, Dialeclica, De
Syll. p. 30. " Prima (Figura) est in qua
medius terminus subjicitur in majore, et in
minore prasdicatur: qiuimcis contrajieri et soleal
etpoasit.''' A Greek, he wrote in Italy for the
Latins; but refers here to the practice of his
countrymen.
Latins: — Cicero, De Fin. iii. 8; iv. 18.
Tiisc. Disp. iii. 7; v. 15, Opera Phil. pp. 885,
903, 981, 1029, ed.Verburgii. 3Iacrobius, Opera,
p. 181, Zeunii. Seneca, Epist. 85, p. 368. Apu-
leius, De Habit. Doct. Plat. L. iii. p 36, ed.
Elmenhorst. Isidorus in Gothofr. Auctores, p.
873. Cassiodorus, DiaUctica, Opera, p. 556,
Genev. 1650, gives alternative, but in Psalm
xxxi. V. 16, gives a syllogism with minor first.
Martianus Capella, De Septem Artibus LiberaU-
bus, allows both forms for liist Figure; gener-
ally makes the minor first (.'^ee below, p. 640).
Boethius (origo mail), v. Opera, p. 594 et sec/.
Orientals.
Mohammedans: — Averroes (enouncing &a-
we) in all the Figures, has minor first. (Sec
below, p. 640 )
Jeivs : — Kabbi Simeon [truly MaimonidesJ,"
(in Hebrew), Logica, per S. Munslerum, cc. G,.
7, Basil, 1527.
Modern anticipations of the doctrine that
the Minor Premise should precede the Major,
Valla, Dialectica, f 60 b, etc. Opera, pp. 733, ,
736. Joannes Neomagus, In Trnpezuntimn , f.
38 b. (only adduces examples). Caramuel,,
Rat. et Realis Philosopkia, Logica, Disp.ix. xvi.
Aquinas, Opusc. 47. (Camerarius, Difp. Phil.
P. i. qu. 13, p. 117.) Alstedius, Encyclopadia,
p. 437. Gassendi, Opera, ii. p. 413; i. p. 107.
Camerarius, Disp. Phil. P. i. qu. 13, p. 117.
Leibnitz, Opera ii. Pars. i. p. 356, Dissert, de
Arte Combinatoria (1666), ed! Dutens, who re-
fers to Ramus, Gassendi, Alcinous, etc. Cf.
Nouveaux Essais, L. iv. § 8, p. 454, ed, Raspo;
and Locke's Essay, ibid. Puffier, Logique, § ,
68. CKsarius, Dialectica, Tract, v. De Syll.
Cat. p. 198 (first ed. 1632). J. C. E. Nova De-
ucta Veritas, etc., see Keusch, Systema Logicum,..
f 547, p. 626. Chauvin, Lexicon Philosophicum,
V. Figura. Hobbes, Computacio, c. iv., prefixes
the minor (see Hallam, Lit. of Europe, vol. iii. .
c. 3,p 309, ed.l839). Lambert, A'euM Organon,
i. 138, § 225. Bachmann, Logik, § 133, pp. 202,
226. Hollmann, Logica, § 454. Esser, Logik,,
§ 107, p. 210. Krug, Logik, § 114, p. 408. Ben-
eke, Sy.-item der Logik, c. v. p. 210 et seg. Stap-
ulensis, in Sergeant's Method to Science, p. 127.
Facciolati (though he errs himself), Rudinunltt
Logicce, p. 86, 1', iii. c. 3, note 4, where Boe-
thius, Sextus Empiricus, Alcinous, etc. Ch.
Mayne, Essay on Natural Notions, p. 122 et seq.
Lamy, Acta Enid., 1708, p. 67.
Who have erred in this subject, — making
our order of enunciation the natural and
u:ual Vives, Censura Veri. Opera, t. i. p.
79
626
APPENDIX.
n. — Figure. — Unfigured and Figured Syllogism.
(1853) (a) CONTRAST AND COMPARISON OF THE VARIOUS KINDS OF FORMAL SYLLOGISM
-DIFFERENCE OF FIGURE ACCIDENTAL.
A.) Unfigured Syllogism — One form of syllogism : for here there is abolished,
1°, The difference of Breadth and Depth, for the terms are both Subject or
both Predicate, and may be either indifferently ; 2°, All order of the terms, for
these maybe enounced from first or second indifferently ; 3°, All difference of
major or minor term of proposition, all duplicity of syllogism ; 4°, All difference
of direct and indirect conclusion.
B.) Figured Syllogism — Two forms of syllogism by different orders of terms :
First Figure. — Here the two forms of syllogism are possible, each with its
major and minor terms, each with its direct or immediate, its indirect or
mediate, conclusion. These two various forms of syllogism are essentially one
and the same, differing only accidentally in the order of enouncement, inasmuch
as they severally depart from one or from the other of the counter, but correl-
ative, quantities of Depth and Breadth, as from the containing whole. But, in
fact, we may enounce each order of syllogism [in] either quantity, the one is
the more natural
Second and Third Figures. — In each of these figures there are possible the
two varieties of syllogism ; but not, as in the first figure, are these different
forms variable by a counter quantity, and with a determinate major and minor
terai; for in each the extremes and the middle term (there opposed) are
necessarily in ihe same quantity, being either always Subject or always Preifi-
cate in the jugation. They differ only as the one extreme, or the other (what
is indifferent), is arbitrarily made the Subject or Predicate in the conclusion.
Indirect or Mediate conclusions in these figures are impossible ; for the indirect
or mediate conclusion of the one syllogism is in fact the direct conclusion of the
other.
Thus difference of Figure accidental.
If rule true, it will follow that it is of no consequence whether —
1°, The middle one or any other of the three terms be, in any proposition,
subject or predicate, if only either. Hence difference of Figure of no account
in varjing tlie syllogism. Thus (retaining the subordination of terms), convert
major proposition in Extension of first Figure, and you have second Figure ;
G06. J. G. Vossius, De Nat. Art. Liberal. , Log-
lea, c. viii. § 9. J. A. Fabricius, Ad. Sext.
Emp. 103. Fncciolali, Rudimenta Logictr, p.
86. Waitz, In Org. Comm., pp. 380, 336.
That Reasoning in Comprehensive Quantity
most natural. Wolf, Pkil. Rat. ^ 399, p. 327.
Reiiscll, Si/steina Logicum, ^ 547. Schuize,
Logik, i 77 of old (1817), i 72 of last (1831)
edition, holds that dictum de omniy etc.,
evolved out of nota notee, for mere subordina-
tion Ryllogisms. Hauschius, in Acta Erud.
17'28, p. 470 Lamy (B.) in Acta Erud. 1708, p.
67. Oldfleld, Ensay on Reason, p. 246. Valla,
Dialectica, L. iii. c. 45. HofTbnuer, Analytik
der UrUuile t/nd Sclililsse, i 152, p. 198. llayne's
Rational Notiomt. p. 123 et seq. Mariotte, Lo-
gique. Part ii , disc. iii. p. 161. Paris, 1678.
Chladenus, Phil. Def. p. 18 (in Wolf, Phil.
Rat. § 551). Castillon, Mem. de Berlin, 1802.
Hallam, Lit. of Europe, vol. iii. p. 309. Thom-
son ( W.), Outlines of the Laics of Thought, p.
39. In reference to the above, the mathema-
ticians usually begin with what is commonly
called the Minor Premise (as A = B, B = C,
there/ore A = C); and frequently they state
theConclusion first(as A = h. for A = iS^and
M = B), or, etc., see Wolf, PhU. Rat. i 561.
and Twesten, Logik, 4 117, p. 105; and Lam-
bert, Neuti Org. i. ( 226-]
APPENDIX. 62T
convert minor proposition, and you have third Figure ; convert both premises,
and you have fourth Figure.
2°, Whelher one of the extremes, one or other of the premises, stand first
or second, be, in fact, major or minor term of a proposition ; all that is required
is, that the terms and their quantities should remain the same, and that they
should always bear to each other a relation of subject and predicate. Thus, if
[in] any of the Figures the major and minor terms and propositions inter-
change relation of subordination ; when, in the first Figure, you convert and
transpose; and when [in] the other three Figures (fourth?), you simply trans-
pose the premises.
Indifferent (in first Figure) which premise precedes or follows. For of two
one not before the other in nature. But not indifferent in either whole, which
term should be subject and predicate of coinclusion.^
(b) DOUBLE CONCLUSION IN SECOND AND THIRD FIGURES.
My doctrine is as follows :
In the Unjigured Syllogism there is no contrast of terms, the notions compared
not being to each other subject and predicate ; consequently the conclusion is
here necessarily one and only one.
In the Figured Syllogism we must discriminate the Figures.
In the First Figure, where the middle term is subject of the one extreme and
predicate of the other, there is of course a determinate major extreme and
premise, and a determinate minor extreme and premise ; consequently, also,
one proximate or direct, and one remote or indirect, conclusion, — the latter
by a conversion of the former.
In the Second and Third figures all this is reversed. In these there is no
major and minor extreme and premise, both extremes being either subjects or
predicates of the middle ; consequently, in the inference, as either extreme
may be indifferently subject or predicate of the other, there are two indifferent
conclusions, that is, conclusions neither of which is more direct or indirect than
the other.
This doctrine is opposed to that of Aristotle and the logicians, who recognize
in the Second and Third Figures a major and minor extreme and premise,
with one determinate conclusion.
The whole question with regard to the duplicity or simplicity of the conclu-
sion in the latter figures depends upon the distinction in them of a major and a
minor term ; and it must be peremptorily decided in opposition to the universal
i doctrine, unless it cq,n be shown that, in these figures, this distinction actually
subsists. This was felt by the logicians; accordingly they applied themselves
with zeal to establish this distinction. But it would appear, from the very
multiplicity of their opinions, that none proved satisfact(Try ; and this general
presumption is shown to be correct by the examination of these opinions in
detail, — an examination which evinces that of these opinions there is no one
which ought to satisfy an inquiring mind.
In all, there are five or six different grounds on which it has been attempted
1 Compare Discussions, p. 653. — Ed.
628 APPENDIX.
to establish the discrimination of a major and minor term in the Second and
Third Figures. All are mutually subversive ; each is incompetent. Each
following the first is in fact a virtual acknowledgment that the reason on which
Aristotle proceeded in this establishment is at once ambiguous and insuffi-
cient. I shall enumerate these opinions as nearly as possible in chronological
order.
1. That the major is the extreme which lies in the Second Figure nearer to, in
the Third Figure farther from, the middle. This is Aristotle's definition (^An.
Pr., L. i. cc. 5, 6). At best it is ambiguous, and has, accordingly, been taken
in different senses by following logicians ; and in treating of them it will be
seen that in none, except an arbitrary sense, can the one extreme, in these
figures, be considered to he nearer to the middle term than the other. I
exclude the supposition that Aristotle spoke in reference to some scheme of
mechanical notation.
2. That the major term in the antecedent is that which is predicate in the con-
clusion. This doctrine dates from a remote antiquity. It is rejected by
Alexander; but, adopted by AmmOnius and Philoponus (f 17 b, 18 a, ed.
Trine), has been generally recognized by subsequent logicians. Its recognition
is now almost universal. Yet, critically considered, it explains nothing. Educ-
ing the law out of the fact, and not deducing the fact from the law, it does not
even attempt to show why one being, either extreme may not be, predicate of the
conclusion. It is merely an empirical, — merely an arbitrary, assertion. The
Aphrodisian, after refuting the doctrine, when the terms are indefinite (prein-
designate), justly says : " Nor is the case different when the terms are definite
[predesignate]. For the conclusion shows as predicate the term given as
major in the premises ; so that the conclusion is not itself demonstrative of the
major ; on the contrary, the being taken in the premises as major, is the cause
why a term is also taken as predicate in the conclusion." — (^An. Pr. f 24 a,
ed. Aid.)
8. That the proximity of an extreme to the middle term, in Logic, is to he decided
hij the relative proximily in nature to the middle notion of the notions compared.
This, which is the interpretation of Aristotle by Herminus, is one of the oldest
upon record, being detailed and refuted at great length by the Aphrodisian
(f 23 b, 24 a). To determine the natural proximity required is often difficult
in affirmative, and always impossible in negative, syllogism ; and, besides the
objections of Alexander, it is wholly material and extralogical. It is needless
to dwell on tliis opinion, which, obscure in itself, seems altogether unknown to
our modern logicians.
4. That the major term in the Syllogism is the predicate of the problem or
question. This is the doctrine maintained by Alexander (f. 24 b) ; but it is
doubtful whether at first or second hand. It has been adopted by Averrocs,
Zabarella, and sundry of the acuter logicians in modern times. It is incompe-
tent, however, to establish the discrimination. Material, it presupposes an
intention of the roasoncr; does not appear ex facie syllogismi ; and, at best,
only shows which of two possible qusesita — which of two possible conclusions
— • has been actually carried out. For it assumes, that of the two extremes
either might have been major in the antecedent, and predicate in the conclu-
sion. If Alexander had applied the same subtlety in canvassing his own
APPENDIX. 629
opinion which he did in criticizing those of others, he would not have given the
authority of his name to so untenable doctrine.
6. That the inajor exii-eme is that contained in the major premise, awl the
major premise .that in the order of enouncement Jirst. This doctrine seems
indicated by Scotus {An. Pr., L. I. qu. xxiv. §§ 5, 6) ; and is held explicitly
by certain of his followers. This also is wholly incompetent. For the order of
the premises, as the subtle doctor him.<elf observes (/6.,qu.xxlii. §6), is altogether
indifferent to the validity of the consequence ; and if this external accident be
admitted, we should have Greek majors and minors turned, presto, into Latin
minors and majors.
C. Thai the major extreme is that contained in the major premise, and the
major premise that itself most general. AH opposite practice originates In abuse.
This opinion, which coincides with that of Herniinus (No. 3), In making the
logical relation of terms dependent on the natural relation of notions, I find
advanced in 1614, in the Disputationes of an ingenious and independent phi-
losopher, the Spanish Jesuit Petrus Hurtado de Mendoza (Disp. Log. et Met., I.,
Disp. X. §§ 50-55). It is, however, too singular, and manifestly too untenable,
to require refutation. As material, it is illogical ; as formal, if allowed, it
would jit best serve only for the discrimination of certain moods ; but it cannot
be allowed, for it would only subvert the old without being adequate to the
establishment of aught new. It shows, however, how unsatisfactory were the
previous theories, when such a doctrine could be proposed, by so acute a
reasoner, in substitution. This opinion has remained unnoticed by posterior
If^icians.
The dominant result from this historical enumeration Is, that, in the Second
and Third Figures, there Is no major or minor term, therefore no major or
minor premise, therefore two indifferent conclusions.
This important truth, however natural and even manifest it may seem when
fully developed, has but few and obscure vaticinations of its recognition during
the progress of the science. Three only have I met with.
The first I find in the Aphrodisian (f. 24 b) ; for his expressions might seem
to indicate that the opinion of there being no major and minor term in the
• second figure (nor, by analogy, in the third), was a doctrine actually held by
jome early Greek logicians. It would be curious to know if these were the
" ancients," assailed by Ammonius, for maintaining an overt quantification of
the i)redicate. The words of Alexander are : — '' Nor, however, can It be
said that in the present figure there is no major. For this at least is determi-
nate, that its major must be universal ; and, if there be in it any syllogistic
combination, that premise is the major which contains the major term" (f.
24 a.). Demurring to this refutation, it is, however, evidence sufficient of the
opinion to which it is opposed. This, as it is the oldest, is, indeed, the only
authority for any deliberate doctrine on the point.
The second indication dates from the middle of the fifteenth centurj', and is
contained In the Dialectica of the celebrated Laurentius Valla (L. ill. c. 8
[51]). Valla abolishes the third figure, and his opinion on the question is
limited to his observations on the second. In treating of Cesare and Camestres,
which, after a host of previous logicians, he considers to be a single mood,
there is nothing remarkable in his statement : " Neque dlstinctae sunt pro-
630 APPENDIX.
positio et assumptio, ut altera major sit, altera minor, sotl quodammodo pares ;
ideoque sicut neutra vindicat sibi primum aut secundum locum, ita utraque
jus habet in utraque conclusione. Verum istis placuit, ut id quod secundo
loco poneretur, vendicaret sibi conclusionem : quod verum esset nisi semper
gemina esset conclusio. Sed earum dicamus alteram ad id quod primo loco,
alteram ad id quod secundo loco positum est referri." We, therefore, await
the development of his doctrine by relation to the other moods, Feslino
and Baroco, which thus auspiciously begins: — "Idem contingit in reliquis
duobus: qui tamen sunt magis distincti." We are, however, condemned to
disappointment For, by a common error, excusable enough in this im-
petuous writer, he has confounded singulars (definites) with particula:-j
(indefinites) ; and thus the examples which he adduces of these moods are,
in fact, only examples of Cesare and Camestres. The same error had also
been previously committed (L. iii. c. 4). The whole, therefore, of Valla's
doctrine, which is exclusively founded on these examples, must go for nothing ;
for we cannot presume, on such a ground, that he admits more than the four
common moods, identifying, indeed, the two first, by admitting in them of
a double conclusion. We cannot, certainly, infer that he ever thouglit of
recognizing a particular, an indefinite, predicate in a negative proposition.
The third and last indication which I can adduce is that from the Melhofl to
Science of John Sergeant, who has, in this, as in his other books (too suc-
cessfully), concealed his name under the initials "J. S." He was a Catholic
priest, and, from 1665, an active religious controversialist; whilst, as a philos-
opher, in his Idea Philonophice Cartesiance, a criticrism of Descartes, in his Solid
PkUosophj, a criticism of Locke,' in his Metaphysics, and in the present work,
he manifests remarkable eloquence, ingenuity, and independence, mingled, no
doubt, with many untenable, not to say ridiculous, paracjoxes. His works,
however, contain genius more than enough to have saved them, in any other
country, from the total oblivion into which they have fallen in this, — where,
indeed, they probably never were appreciated. His Method to Science (a
treatise on Logic) was published in 1696, with a " Preface, dedicatory to tlio
learned students of both our Universities," extending to si.xty-two pages. But,
alas ! neither tliis nor any other of his philosophical books is to be found in the
Bodleian.
In the third book of his Method, which treats of Discourse, after speaking
of the first, or, as he calls it, "only right figure of a syllogism," we lia\e llio
following observations on the second and thirtl : — "§ 14. Wherefore the other
two figures [he does not recognize the fourihj are tmnatura! and monstrous.
For, since nature has shown us, that M'hat conjoins two notions ought to be
placed in the middle between them ; it is against nature and reason to place it
either above them both, as is done in that they call the second Jiyure, or under
them both, as is done in that figure they call the third.
"§ 15. Hence no determinate conclusion can follow, in either «f the last
1 Sergeant is an intelli;jent antagonist of man Undrrstamting. In certain rjews he an-
both these philosupherv, and I have elsewhere ticipates Kant : and Tope lias evidently taken
had occasion to quote him as the first and from his brother Catholic the hint of some uf
one of the ablest critics of the Essay on Hu- his most celebrated thoughts.
APPENDIX. 631
figures, from the disposal of the parts in the syllogisms. For since, as appears
(§ 13), the extreme which is predicated of the middle term in the major, has
thence a title to be the predicate in the conclusion, because it is above the
middle term, which is the predicate, or above the other extreme in the minor, it
follows, that if the middle term be twice above or twice below the other two
terms in the premises, that reason ceases; and so it is left indifferent which of
the other terms is to be subject or predicate in the conclusion ; and the inde-
terminate conclusion follows, not from tlie artificial form of the syllogism, but
merely from the material identity of all the three terms ; or fi-om this, that
tlieir notions are found in the same Ens. Wherefore, from these premises [in
the second figure],
Some laudable thing is [all] virtue,
[All] courtesy is a virtue ;
or, from these [in the third],
[All] virtue is [some] laudable,
Some virtue is [all] courtesy ,•
the conclusion might either be,
Therefore, [all] courtesy is [some] laudable,
Or, Some laudable thing is [all] courtesy.
So that, to argue on' that fashion, or to make use of these awkward figures, is
not to know certainly the end or conclusion we aim at, but to shoot our bolt
at no determinate mark, since no determinate conclusion can in that case fol-
low." (P. 232.)
Extremes, it is said, meet. Sergeant would abolish the second and third
figures, as petitory and unnatural, as merely material corruptions of the one
formal fiist. I, on the contrary, regard all the figures as equally necessary,
natural, and formal. But we agree in this : both hold that, in the second and
third figures, there is a twofold and indifferent conclusion ; howbeit, the one
makes this a monstrosity of the syllogistic matter, the other, a beauty of the
syllogistic form. Therefore, though I view Sergeant as wrong in his premises,
and " shooting his bolt at no determinate mark," I must needs allow that he
has, by chance, hit the bull's eye. I have inserted, within square brackets, the
quantifications required to restore and show out the formality of his examples.
On my scheme of notation, they stand as follows :
63^
APPENDIX.
HL — HisTOsiCAL Notices Regakdixg Figure of Stlu>gisk.
(a) ARISTOTLE.
Aristotle ; Figures and Terms of Syllogism, Prior Analytics, B. I. ch. iv.
First Figure, ch. iv. — § 2. " When three terms [or notions] hold this mutual
relation, — that the last is In the whole middle, whilst the middle is or is not
in the whole first, — of these extremes there results of necessity a perfect
syllogism.^
§ 3. " By middle term [B (B)] I mean that which itself is in another and
another in it ; and which in position also stands intermediate. I call extreme
both that which is itself in another [the minor], and that in which another is
[the major]. For if A be predicated of all B, and B of all C, A will neces-
sarily be predicated of all C.
§ 10. "I call that the major extreme [A (A)] in which the middle is; the
minor [F (C)] that which lies under the middle."
Second Figure, ch. v. — § 1. "When the same [predicate notion] inheres in
all of the one and in none of the other, or in all or in none of both [the sub-
ject notions], — this I denominate the Second Figure.
§ 2. " The middle [M (M)] in this figure I call that which is predicated of
both [notions] ; the extremes, the [notions] of which the middle is said. The
major extreme [N (N)] is that towards the middle ; the minor [H (O)], that
from the middle more remote.
§ 3. " The middle is placed out [from between] the extremes, the first in
position" —
lSo,M
N
H-
M
N
O
Third Figure, ch. vi. — § 1. "When in the same [subject notion] one
[predicate notion] inheres in all, another in none of it, or when both inhere in
all or in none of it, such figure I call the Third.
§ 2. " In this [figure] I name the middle, that of which both [the other terms]
are predicated ; the extremes, the predicates themselves. The major extreme
[ n (P)] is that farther from, the minor [P (Q)] that nearer to, the middle.
1 Ch. iv. s 2 — This definition of the First
Figure (founded on the rules De Omni and de
Nullo) applies only to the universal moods,
but, of these, only to those legitimate and
useful, — Barbara and Celareiit. It, there-
fore, seems inadequate, but not superfluous.
Aristotle uses the phrase " to be in all or in
the whole," both with reference to extension,
— for the lower notion B, as contained under
the all or whole of the higher notion A ; and
with reference to comprehension, — for the
higher notion A as contained in the all or
whole of the lower notion B. In the former
sense, which with Aristotle is the more usual,
and, in fact, the only one contemplated by
the logicians, there is also to be observed a
distinction between the inhesion and the pre-
dication of the attribute.
APPENDIX. 633
§ 3. " The middle [2 (R)] is placed out ^[from between] the extremes, the
last in position,"
[As, n P 1
P Q
2 R
Aristotle, Prior Analytics, B. i. c. 23, § 7.
General Theory of Figure. — " If, then, it be necessary [in reasoning] to
take some [term] common [or intermediate] to both [extreme terms] ; this is
possible in three ways. For we predicate either [the extreme] A of [the
middle] C, and [the middle] C of [the extreme] B ; or [the middle] C of both
[extremes] ; or both [extremes] of [the middle] C. These are the [three]
Figures of which we have spoken ; and it is manifest, that through one or other
of the Figures every syllogism must be realized."^
C) and (c) - ALEXANDER AND HERMINUS.
Alexander, In An. Pr., f. 23 b.
Second Figure, c. v. Aristotle. — " ' The middle extreme is that which lies
towards the middle.'
§ 2. " But it is a question, whether in the Second Figure there be by nature
any major and minor extreme, and if there be, by what criterion it may be
known. For if we can indiiferently connect with the middle term whichsoever
extreme we choose, this we may alwajs call the major. And as negative con-
clusions only are drawn in this figure, universal negatives being also mutually
convertible, it follows, that in universal negatives the one term has no better
title to be styled major than the other, seeing that the major term is what is
predicated, whilst both are here indifferently predicable of each other. In
universal affirmatives, indeed, the predicate is major, because it has a wider
extent; and for this reason, such propositions are not [simply] convertible ; so
that here there is by nature a major term which is not to be found in universal
negatives.
" Herminus is of opinion that, in the Second Figure,
[1°.] " If both the extremes, of which the middle is predicated, be homoge-
neous [or of the same genus], the major term is that most proximate to the
genus common to the two. For example : If the extremes be Urd and man ;
bird lying nearer to the common genus [^ani7nal'] than man, as in its first
division, bird is thus the major extreme ; and, in general, of homogeneous
terms, that holding such a relation to the common genus is the major.
[2°.] " But if the terms be equally distant from the common genus, as Zto?\s-e
and man, we ought to regard the middle predicated of them, and consider of
1 Ariptof le liere varies the notation by let- notation mi^^ht appear to indicate) that the
ters of the tliree syllogistic terms, making C middle term was a notion in the First Figure,
(!') stand for the middle term, A and 15 for necessarily intermediate between tlie two ex-
the two extremes. This he did. perhaps, to tremes, in the Second superior, in the Third
prevent it being supposed (what his previous inferior, to them.
80
634
APPENDIX.
which [term] it is predicated through [that term] itself, and of which through
some other predicate ; and compare that through which it is predicated of
another with that through which it is predicated of [the term] itself. And if
that through which [the middle] is predicated of another (viz. the one extreme)
be nearer [than the other extreme] to the common genus, that [extreme] of
which [for tovjoiv ov, I read tovtov ovJ the middle is [mediately] predicated,
from its closer propinquity to the common genus, rightly obtains the title of
major. For example : If the extremes be horse and 7nan, rational being predi-
cated of them, — negatively of horse, affirmatively of man ; seeing that rational
is not of itself denied of horse, but because horse is irrational, whereas rational
is of itself affirmed of man, horse is nearer than 7nan to their common genus
animal ; horse will, therefore, be the major extreme, though man be no further
removed than horse from its proper genus. And this, because that through
which the predicate [i. e. the middle] is predicated of this last, as being
irrational, is greater ; for rational is not denied of horse qua horse, whilst it is
affirmed of man qua man.
[3°.] " But if the extremes be not homogeneous, but under diiferent genera,
that is to be considered the major term, which of the two holds the neai-er of
its own genus. For instance: If aught be predicated of color and man, color
is the major extreme ; for color stands closer to quality than man to substance :
as man is an individual [or most special] species, but not color.
[4°.] " Finally, if each be equally remote from its proper genus, we must
consider the middle, and inquire of which term it is predicated through [that
term] itself, and of which through something else ; and if that, through which
the middle is predicated of another [/. e., one extreme], be nearer to its proper
genus, and if through that the middle be actually predicated of this term, this
term is to be deemed the major. For example: If the terms be white and
man, the one being an individual species in quality, the other in substance ;
and if rational be alfii'matively predicated of man, negatively of tchite ; the
affirmation is made in regard to man as man, whereas the negation is made of
white, not as white, but as inanimate. But since inanimate, through which
rational is denied of white, is more common, more universal, and more proxi-
mate to substance inanimate than man to \fubstance'\ animate, on that account,
white is the major term in preference to man." [So far Herminus.]
" But to reason thus, and to endeavor to demonstrate a major term by nature,
in the Second Figure, is a speculation which may be curious, but is not true.
[I read irpbs tw.]
[1°.] " For, in the first place, if we consider the given terms, not in them-
selves, but in relation to others, in which the predicated term docs not inhere ;
the major term will be always found in the negative proposition. For, in this
case, the major is always equal to the middle term ; since, whether it be thus or
thus taken froui the commencement, or be so made by him who denies it, 'ho
negative major will still stand in this relation to the middle term. For the mid-
dle does not inhere, where it is not supposed to inhere. Wherefore, its repug-
nant opposite inheres in the subject, but the repugnant opposite of the middle
IS ecjual to the middle. And this, either througii the middle itself, or through
another notion of wider extent ; as when ralional is denied of something through
inanimate. For there \s here an equalization through irrational, through which
APPENDIX. 635
rational is negatively predicated of horse. For either the middle is equal to
this of which it is denied, or [I read tj for 6] it is less ; as when through inani-
mate, rational is denied of aught. For inanimate is equal to animate, under
which is rational, a notion greater than that other of which it is affirmed. For
since the affirmative predicate is greater than its subject, of which the middle is
denied or not affirmed ; and since the reason why the middle is denied is equal
to or greater than the middle itself, which middle, again, in an affirmative
proposition, is greater than its subject ; — on these accounts a negative propo-
sition is always greater than an affirmative. Nevertheless, Aristotle himself
says that a negation is to be placed in the minor [proposition] ; for the second
syll(^sm in this figure [Camestres] has as its minor premise a universal
negative.
[2°.] " Further, why in the case of negatives alone should explanation or
inquiry be competent, in regard to the reason of the negative predication,
seeing that in the case of affirmatives the reason is equalK' an object of inquiry ?
For rational is predicated of man, of itself, indeed, but not primarily, that is,
not inasmuch as he is man, but inasmuch as he is rational ; so that if rational
[be denied] of horse through irrational, still these are both branches of the
same division. By this method, assuredly, no major can be ever found.
Wherefore, we ought not, in this way, to attempt a discrimination of the major
of affirmative syllogisms in the Second Figure. For in this figure affirmation
and negation are equally compatible with the major term ; so that whatsoever
term has by the foremeutioned method been found major, the same, taken
either as major or minor, will effectuate a syllogistic jugation ; which being
competent, there is no longer any major [or minor] in this figure. For the
problem is to find not a major term absolutely, but one of this figure." [So
much touching Herminus.]
[3°.] " Nor, on the other hand, as is thought by some, is that unconditionally
to be called the major term which stands predicate in the conclusion. For
neither is this manifest; if left indefinite [preindesignate], the same term will
hold a different relation, though a conversion of the universal negative; so
that what is now tlie major, may be anon the minor. We may, in fact, be
said to constitute the same term both major and minor. Naturally there is in
negative propositions no major notion, nor, from the conclusion, ought we to
make out the major at all. Nor is the case different when the term is defined
[predesignate]. For the conclusion shows, as predicate, the terfli given as
major in the premises ; so that the conclusion is not itself demonstrative of the
major; on the contrary, the being taken in the premises as major is the cause
why a term is also taken as predicate in the conclusion.
" Nor, however, can it be said that in this figure there is no major. For this
at least is determinate, — that its major must be universal; and, if there be
[in it] any syllogistic combination, that premise is the major which contains the
major term.
[4°.] " But, in the Second Figure, -which of the terms is to be deemed the
major ? Tliat is to be deemed the major, and to be placed first, which in the
problem [question or quajsitum] we intend to demonstrate, and which we
regard as predii;ate. For every one who reasons, first of all determines with
himself what it is he Tvonid prove ; and to tliis end lie applies his stock of
G36
APPENDIX,
suitable propositions ; for no one stumbles by chance on ■» conclusion. The
notion, therefore, proposed as predicate in the problem to be proved, is to be
constituted the major term ; for although the proposition be converted, and the
notion thereby become the subject, still, in what we proposed to prove, it
[actually] was, and, therefore [virtually], remains, the predicate. Hence, even
if there be drawn another conclusion, we convert it ; so that, to us who prove
and syllogize and order terras, that always stands as the major. For major and
minor are not, in negative syllogisms, regulated by their own nature, but by
the intention [of the reasoner] to conclude. Thus it is manifest, that what is
the predicate in the problem, is also the predicate in the conclusion."
Alexander on Prior Analytics, L. i. c. vi. f. 30 a. ed. Aid.
(Third Figure.) . . , This is the Third Figure, and holds the last place
because nothing universal is inferred in it, and because sophistical syllogisms
chiefly affect this figure with their indefinite and particular conclusions. But
the sophistical are the last of all syllogisms. . • . Add to this, that while
both the Second and Third Figures take their origin from the Fii-st of the
two, the Third is engendered of the inferior premise. For the minor, qua
minor, is the inferior premise, and holds reasonably a secondarj- place [the
conversion of the minor jjroposition of the first figure giving the second figure].
F. 30 b. (Darapti). " The first syzygy in this figure is of two universal
affirmatives [Darapli]. But it may be asked — Why, whilst in the second
figure there are two syllogistic conjugations, having one of the premises a
universal aflHrmative, the other a universal negative (from having, now their
major, now their minor, as a universal negative proposition converted^, — why,
in the third figure, there is not, in like manner, two syllogistic combinations of
two universal afliinnatives, since of these either the major or the minor propo-
sition is convertible ^ Is it that in the second figure, from the propositions
being of diverse form [quality], the commutation of a universal negative into
^omctliiitg else by conversion is necessary, this being now the major, iiow the
minor, ami it not being in our power to convert which we will? In the thirtl
figure, on the other hand, there being two universal affirmatives, the position
[relation] of the propositions (for they are similar in character and position) is
not tlie cause of one being now converted, now another; the cause lying in us,
not the jiigation. Wherefore, the one or other being similarly convertible,
inasmuch as the position [relation] of the two propositions is the same; the
one which affords the more important probation is selected, and hereby is
determined the syllogistic jugation. Moreover, the differences of syllogism
[moods] in each figure are effected by the differences among their jugations,
not by those among their probations. Thus that the combination of proposi-
tions is syllogistic [or valid], is proved by conversion and reductio ad impossibile,
al.-o by exposition. But from this circumstance there does not emerge a plu-
wlity of syllogij^ms [moorls]. For the different probations [are not valid from
such plurality, but] from the unity of the jugation from which they are inferred,
so that one jugation of two universal affirmatives may constitute, in the third
figure, a single syllogism [mood], howbeit the probations are different ; ina.<i-
much as now the one, now the other, of the propositions can be converted."
APPENDIX. 637
(d) - PHILOrOXUS.
Philoponus (or rather Ammonius) on Aristotle, An. Pr., i. 4, § i. f. 17 a, ed.
Trincavelli, 1536.
" The Predicate is always better than the subject, because the predicate is,
for the most part, more extensive (^M Trxiov) than the subject, and because the
subject is analogous to the matter, the predicate to the form ; for the matter is
the subject of the forms. But Avhen the middle term is predicated of the two
extremes, or is the subject of both, in this case it is not properly intermediate.
But, howbeit, though in position external to the middle, it is still preferable to
be the predicate than to be the subject. On this ground, that is called the
first figure, the middle term of which preserves its legitimate oi-der, being
subject of the one extreme, and predicate of the other. The second figure is
that in which the middle is predicated of both extremes, and in which it occu-
pies the better position of those remaining. Finally, the third figure is that in
which the middle term is subjected to the two extremes ; here obtaining only
the lowest position. Wherefore, in the first figure the middle term is delineated
on a level with the extremes ; whereas in the second it is placed above, and in
the third beloio, them."*
Philoponus (or rather Ammonius) on Aristotle, An. Pr., f 17 a, ed. Trinca-
velli, 1536.
Syllogistic Figures in general. — " We must premise what is the Major
Proposition of the Syllogism, and what the Minor. But to understand this,
we must previously be aware what are the Major and Minor Terms. And it
is possible to define these, both, in common, as applicable to all the three
figures, and, in special, with reference to the first alone. In the latter relation,
that is, regarding specially the first figure, the Major Term is that which consti'
lutes the Predicate, the Minor that tvhich constitutes the Subject, of the Middle, so
far as limited to the first figure. But since in neither of the other figures do
the extremes reciprocally stand in any definite (?) relation to the middle term,
it is manilest that this determination is inapplicable to them. We must, there-
fore, employ a rule common to all the three figures ; to wit, that the major
term is that predicated, the minor that sid>jected, in the conclusion. Thus, the
Major Proposition is the one containin;/ the Major Term ; the Alinor Proposition
the one containing the Minor Term. Examples : Of the First Figure, — Man
[w] animal ; animal, substance : therefore, man, sidistance Of the
Second, — Animal [is predicated] of all man; animal of no stone; man, there-
1 Ammonius, or Philoponus, here mani- AVliether these diaptrams ascend higher than
lestiy refei-s to the diagrams representing the Ammonius does iiot appear; for tliey are
three tigures, and accommodated to Aris- probahly not the constructions referred to by
totle's tliree sets of letters, noting tlie thiee Aristotle; and none are given by the Aphro-
terms in each of these; thus: disian in his original text, though liberally
„ a y u v f> supplied by his J.atin translator. The dia-
grams of Ammonius were long generally em-
ployed. By Neomagus, 1533 (In Trnpe.zuntii
Dialect., f. 35), they are most erroneously re-
ferred to Faber Stapuleusis. [See further.
Discussions, p. C70. — Eo. |
638 APPENDIX.
fore^ of no stone Of the Third, — Some stone i.< tchite ; all stone is
inanimate : consequently, some while is inanimate."
First Figure. — F. 19 b, 59; Aristotle, /. c. § 3. '"But I call that the
middle term which itself is in another, and another in it ; and which in position
lies intermediate.'
" This definition of the middle term is not common to the three figures, but
limited to the middle of the first figure only. For, etc But, if there
be a certain difference in ypecies between the middle terms of the three
figures, they have likewise something in common ; ti> wit, that the middle term
is found twice in the premises, throughout the throe figures ; which also in
position is middle. For Aristotle wishes in the Diagraph (if avrfj rp Karaypcuprj)
lo preserve the order of intermediacy, so that, placing the three terms in a
straight line, we assign the middle place to the middle term. ['?]
Aristotle, l. c. § 4. " ' But [I call] the extremes both that which is in another,
and that in which another is. For if A be predicated of all B, and B of all
C, it is necessary that A should also be predicated of all C. We have previ-
ously said what we mean by the expression [predicated] of all.' "
" It may seem, perhaps, that this is a [perfect] definition of the extremes and
of the middle term. But it is not ; for it behooves us to sub-undei-stand, in
addition, the word only ; and thus the definition will rightly run, — But [I call]
the extremes, both that which is in another [minor], and that in which another
is [major]. For if A be predicated of all B, and B of all C, it is necessary
that A be predicated of all C.
" This the first syllogistic mood is of two aflirmative universals, collecting an
affirmative conclusion. For if B inheres in all C, C is, consequently, a part of
B. But B is a part of A ; A therefore, also, inheres in all C, C being a part
of B. The reasoning will be plainer in material examples — as substance [is
predicated] of all animal : animal of all man; and there is inferred substance
of all man: and conversely, a// man [is] animal; all animal substance ; there-
fore, all man substance.
" But it is manifest how, in this figure, the term of the first mood [Barbara]
ought to be taken. The first is the most general, and the second the subaltern,
genus; whilst the third is a species moi"e special than the middle. The con-
clusion ought always to be drawn. Thus, if, proceeding synthetically, we
commence by the major term [and proposition], substance begins ; wherefore it
also leads the way in the conclusion. [There is predicated] substance of all
animal (here .<iubstance commences) ; animal of all man ; whilst the conclusion
again commences with substance, — substance of all man. But if we start from
the minor term [and proposition], as from man, with this also the conclusion
will commence ; all man [is] animal ; all animal substance ; all man substance.
" Aristotle takes the terms A, B, C ; and, from the relation of the letters, he
manifests to us the order of the first figure. The major term he calls A,
because A stands first in order; the minor term C ; and the middle terin B; as
B, in its order, follows A, and precedes C.
" It is plain that the terms may possibly be coadequate [and therefore recip-
i-ocating] ; as receptice of science — risible — man; for all man is risible; all
risible is receptive of science ; therefore, all man is receptive of science."
APPENDIX. 639
F. 23 b. Aristotle, ch. 5, § 2, Second Figure. " ' The major extreme is that
which lies nearer to the middle ; the minor, that which lies farther from the
middle.'
" In place of more akin and more proximate to the middle ; not in position,
but in dignity. For since, of the terms, the middle is twice predicated, while,
in the conclusion, the major is once predicated, but the minor not even once
predicated ; [consequently] that which is once predicated will be the more
proximate to that which is twice predicated, that is, to the middle, than that
which is not even once predicated. Wherefore, we shall hear him [Aristotle],
in the Third Figure, calling the minor the term more proximate to the middle
on account of their affinity, for they are both subjects, while he calls the major
term the more remote. Perhaps, also, he wishes that in the diagraph (rp
Karaypafij) the major term should be placed closer to the middle, and the minor
farther off. But the major extreme in this figure, the two premises being uni-
versal, exists not by nature but by position, for the first of the extremes which
you meet with as a subject in the second figure, — this is the minor extreme,
the other is the major. So in the example — All man an animal; no plant
animal ; therefore, no man plant. In like manner, if we take the commence-
ment from plant, this becomes the minor term, and man the major ; as, no plant
animal; all man animal : no plant, therefore, man. Consequently the major
and minor terms exist in these examples only by position, not by nature.
If, indeed, one or other of the propositions be particular, the major and the
minor terms are then determined ; for we hold that in this figure the universal
is the major."
Aristotle. — §3. "'The middle is placed external to [not between] the
extremes, and first in ])osition.'
" The middle term passes out of what is properly the middle position ; it is
also placed out of or external to the extremes ; but either above these or below.
But if it be placed above, so as to be predicated of both, it is called first in
position ; if below, so as to be subjected, it is called second. AVherefore, here,
as predicate of both premises, he styles the middle term the first ; for if it be
placed above, it is first in position, and in being apart from the extremes, it is
placed without them."
Aristotle, ch. 6, § 2. Third Figure, f 27 b. " ' The major extreme is that
more remote from, the minor is that more proximate to, the middle.'
" The major term in this figure is twice predicated of the middle, and in the
conclusion ; but the minor once only, and that of the middle, for it is subjected
to the major in the conclusion ; the middle alone is subjected, never predicated.
When he, therefore, says that the major term is more remote from the middle,
he means the term always predicate is in affinity more remote from that which
is never predicate, but always subject. And that which is never subject is
the major and more proximate term ; that again, which is now subject, now
predicate, is the minor."
(e) MARTTANUS CAPELLA.l
Martianus Capella, De Sepiem Artibus TAberalibus, L. iv. De Dialectica, in
1 Flourished A. C. 457, Passow ; 474, Tennemann.
640
APPENDIX
capite, Quid sit Predicativus Syllogismus, p. 127, ed. Grotii; p. 83, ed. Basil.
1532.
" Hujus generis tres form£E [figuras] sunt.
" Prima est, in qua declarativa [praedicatum] particula superioris sumpti,
seqaentis efficitur subjectiva [subjectum] ; aut subjectiva superioris, declarativa
sequentis. Declarativa superioris fit subjectiva sequentis, ut Omnvi voluptas
bonum est ; omne honum utile est ; omnis igilur voluptas utilis est. Subjectiva
superioris fit declarativa sequentis, si hoc modo velis convertere : Omne bonum
utile est; omnis voluptas honuin est; omnis igitur voluptas utilis est."
In First Form or Figure, notices the four direct and five indirect moods, —
reflexion ; and, in the second and third, the usual number of moods.*
In Second Figure — " Hie reflexione si utaris, alius modus non efficitur,
quoniam de utrisque subjectivis fit illatio." He seems to hold that two direct
conclusions are competent in Second and Third Figures.
In Second Figure he enounces generally (four times) as thus : — '■^Omne jus^
turn honestum ; nullum turpe honestum ; nullum igitur justu7n turpe ; " but some-
times (once) thus, — " Nullum igilur turpe Justum."
. In Third Fonn or Figure generally (six times) thus, as — ^'' Omne justum
honestum; omne justum bonum; quoddam igitur honestum bonum;" but some-
times (once) as — ^'Quoddam igitur bonum honestum."
CO ISWORUS.
Isidorus, Originum, L. i. c. 28. De Sgllogismis Dialecticis. Opera, p. 20
(1617) ; in Gothofred. Auctores, p. 878.
" Formulae Categoricorum, id est, Praedicativorum Syllogismorum sunt tres.
Primae formulae modi sunt novem.
" Primus modus est qui conducit, id est, qui colligit ex universalibus dedica-
tivis dedicativum universale directim : ut, Omne justum honestum ; omne hones-
tum bonum ; ergo omne justum bonum." All in first figure, with minor first ; in
second and third figures, varies ; uses per reflexionem et reflexim indifferently ;
and through all moods of all figures follows Apuleius. " Has formulas Cate-
goricorum Syllogismorum qui plene nosse desiderat, librum legat qui inscribitur
PerHiermenias Apulcii, et quae subtilius sunt tractata cognoscet."
(») AVERItOES.
Averroes, In Anal. Prior, L. i. c. v., on First Figure. — " If, therefore, the
middle term be so ordered between the two extremes, that it be predicated of
the minor and subjected to the major (as, if Ave say all C is B, and all B ts A) ;
it is plain that tliis order of syllogism is natural to us; and it is called by
Aristotle the First Figure." And tims are stated all the examples in detail.
C. vi.. Figure Second. — "And the proposition whose subject is the subject
1 Cassiodorus, in First Figure, gives both
forms, " vel sic;" in Second and Third,
though he gives also a "vcl'sic," they are
examples, both in converse, of Capella's gen-
eral mode of enunciation. See Dialect., Opera,
pp. 538, 556, Genev. 1650, and above, p. 626
(fl 520). Cf. Apuleius, De Si/Uogismo Cntegor-
ico. Op., p. 35. Elmen. (A. c. 160). Isidorus,
of Seville ( Got/io/r. Auct., p. 878), (A. c. 600;
died 636)
APPENDIX. 641
of the quaasitum is the minor proposition, but that whose subject is the pred-
icate of the (juaesitum is the major. Let us then place first in order of enun-
ciation the minor extreme ; let the middle term then follow, and the major
come last, to the end that thus the major maybe distinguished from the minor;
for in this figure the terms are not distinguished, unless by relation to the
(jusesitum." So all the examples.
C. vii.. Third Figure. — " That proposition in which lies the subject of the
quaesitum is called the minor proposition, since the subject itself is called the
minor term ; that proposition which contains the predicate of the quaesitum is
named the major. In the example, let the minor term be C, the middle B, and
the major A, and their order be that we first enounce the middle, then the
minor, and last of all the major." And so the examples.
(h) MELANCHTHON.
Melanchthon, Erotemata DialecHcce, L. iii. p. 1 75.
" Demonstration why there are necessarily three [and only three] Figures.
" Every argumentation which admits the syllogistic form (for of such form In-
duction and Example are not recipient [?]) proceeds either [1°], From genus,
to species universally with a universal conclusion ; or [2°], From species to-
^enus with a particular conclusion ; or [3°], A distraction of two species take.s
place; or [4°], There is a concatenation of a plurality of causes and effects.
Nor are there more modes of argumentation, if we judge with skill.
" The process from genus to species engenders the First Figure. And, the
consequence is valid from the genus with a universal sign both affirmatively and
negatively to the species, — this 'is naturally manifest. The process from
.'species to genus with a particular conclusion engenders the Third Figure.
And it is evident that, the species posited, the genus is posited. ,
" The distraction of species engenders the Second Figure. And the reason
of the consequence is clear, because disparate species are necessarily sundered.
These may be judged of by common sense, without any lengthened teaching
Both are manifest, — that the figures are rightly distributed, and th^t the con-
sequences are indubitably valid."
(i) ARNAULD.
Amauld, EAirt de Penser (Port Royal Logic), P. iii. ch. 11, p. 235. —
General principle of syllogisms : — " That one of the premises^ should contain
the conclusion, and the other show that it does so contain it." — [So Purchot,
Instil. Phil, Vol. I. P. iii. ch. 1.]
Ch. v., p. 215. —" Foundation of First Figure."
" Principle of affirmative moods : — That what agrees loitJt a notion taken uni-
versally, agrees also with all of which this notion is affirmed ; in other words, with
all that vi the subject of this notion, or is composed ivithin its sphere." [Or, more
shortly (says Purchot, c. vi.). Whatever is predicated of the superior, is pred-
icated of the inferior.']
" Principle of the negative moods : — What is denied of a notion taken uni-
versally, is denied of all whereof this notion is affirmed." [Purchot — What is
repugnant to the superior, is repugnant also to the inferior. Ch. vi. p. 217.]
81
642 ' APPENDIX.
•' Foundation of the Second Figure.^ Principle of the syllogisms in Cesare
and Festino: — That what is denied of a universal notion, is denied also of
whatever this notion is affirmed, that is to say, of all its subjects.
" Principle of the syllogisms of Camestres, Baroco : — All that is contained
under the extension of a universal notion, agrees with none of the subjects whereof
that notion has been denied, seeing that the attribute of a negative proposition is
taken in its whole extension."
Ch. vii., p. 220. " Foundation of the Third Figure.
" Principle of the affirmative moods : — When two terms may he affirmed of
the same thing, they may also be affirmed of each other, taken particularly. [So
Purchot nearly.]
"Principle of the negative moods: — When of two terms the one may be
denied, and the other affirmed, of the same thing, they may be particularly denied
of each other." [So Purchot nearly.]
No foundation or principle given for the Fourth Figure.
0) GROSSES.
Samuelis Grosseri, Pharus Intellectus, 1697, P. iii. S. i. Mem. 3, c. 2 (prob-
ably from Weiss, see Pref ). — " The foundation of the first figure is the Dic-
tum de Omni et Nullo ; for whatever is universally aflirmed or denied of a
universal subject, tliat is also affirmed or denied of all and each contained
under that subject.
" The foundation of the second figure is Contrariety ; for the predicates of
contrary things are contrary.
" The foundation of the third figure is the agreement of the extremes in any
third ; for what agrees with any third agrees with each other, and may be
joined or separated in the same proposition, inasmuch as they are in agree-
ment or confliction in relation to any third thing."
Illustrates the three figures by three triangles, p. 132. In the first, we ascend
to the apex on one side, and descend on the other ; in the second, we ascend at
both sides ; in the third, we descend on both sides.
(t) LAMBERT.
Lambert, Neues Organon, Vol. I. § 225. (See Melanchthon, p. 641.)
Relation of Figures. — " We further remark, that the first discoverer of Syl-
logisms and their Figures was, in his arrangement of their propositions, deter-
mined by some arbitrary circumstance ; his views and selections at least were
not founded on aught natural and necessarj' (§ 196). He places, to wit, that
premise after the <>ther which contains among its terms the subject of the con-
clusion, probably in order to introduce into all the figures a common law. To
that law, however, we do not restrict ourselves either in speech or in writing.
The mathematician, who, perhaps, draws the greatest number of formal syllo-
gisms with the fewest paralogisms, commences to take the first figure, for exam-
1 Purchot says this Figure rests upon a sin- but something agrees with the one, which it re-
gie principle — Two things are not the tame, pugnaM to the other.
APPENDIX. 643
pie, not ■nith the major, but with the minor proposition, because not only in
this figure is such premise always the more obtrusive, but also because its sub-
ject is the proper matter of discourse. Frequently the premise Is only quoted,
or it is absolutely omitted whensoever it is of itself obvious to the reader, or is
easily discoverable from the minor and conclusion. The conclusion inferred is
then, in like manner, constituted Into the minor proposition of a new syllogism,
wherewith a new major Is connected. This natural arrangement of the syllo-
gisms of the first figure rests, consequently, altogether on the principle, — 2'Tiat
we can assert of (he subject of an affirmatice proposition whatever we mai/ know
of its predicate ; or what may he said of the attribute of a thing is valid of the
thing itself. And this is what the syllogisms of the first Figure have peculiar
to themselves. It Is also so expressed : — What is true of the genus, is true also
of each of its species.
§ 226. " On the other hand. In the second and third Figures there is no
talk of species and genera. The second Figure denies the subjects of each
other, because they are diverse in their attributes ; and every difference of
attribute Is here effectual. We, consequently, use this figure principally in the
case where two things ought not to be intercommuted or confounded. This
becomes necessarily Impossible, so soon as we discover in the thing A something
which does not exist in the thing B. We may, consequently, say that syllo-
gisms of the second figure lead us to distinguish things, and prevent us from
confounding notions. And it will be also found that in these cases we always
use them.
§ 227. " The third Figure affords Examples and Exceptions ; and, in this
Figure, we adduce all exempla in contrarium. The two formula are as follows :
" 1. There are B which are C ; for M is B and C.
" 2. There are B which are not C ; for M is B and not C.
" In this manner Ave draw syllogisms of the Third Figure, for the most part,
in the form of copulative propositions (§ 135) ; because we are not wont twice
to repeat the subject, or to make thereof two propositions. Sometimes one
proposition is wholly omitted, when, to wit. It is self-manifest.
" In the Fourth Figufe, as In the First, species and genera appear only with
this difference, that in the moods, Baralip, Dibatis, Fesapo, Fresison, the infer-
ence is from the species to the genus ; whereas, in Calentes, there is denied of
the species what was denied of the genus. For where the genus is not, neither
are there any of Its species. This last mood we, therefore, use when we con-
clude negatively a niinori ad majus, seeing that the genus precedes, and is more
frequently presented than any of its species.
§ 229. " The syllogisms of the four Figures are thus distinguished In relation
to their employment, in the following respects :
" 1. The First Figure ascribes to the thing what we know of Its attribute.
It concludes from the genus to the species.
" 2. The Second Figure leads to the discrimination of things, and relieves
perplexity in our notions.
" 3. The Third Figure affords examples and exceptions in propositions which
appear general.
" 4. The Fourth Figure finds species in a genus in Baralip and Dibatis ; it
644
APPENDIX.
shows that the species does not exhaust the genus in Feaapo, Fresison ; and -it
denies the species of what was denied of the genus in Calentes.
§ 230. " This determination of the difference of the Four Figures is, abso-
lutely speaking, only manifested when we employ tht-m after natural fashion,
and without any thought of a selection. For, as the syllogisms of every figure
admit of being transmuted into those of the first, and partly also into those of
any other, if we rightly convert, or interchange, or turn into propositions of
equal value, their premises ; consequently, in this jjoint of view, no difference
subsists between them ; but whether we in every case should perform such vow-
mutations, in order to bring a syllogism under a different figure, or to assuru
ourselves of its correctness, — this is a wholly different question. The latter
.is manifestly futile. For, in the commutation, we must always undertake a
conversion of the premises, and a converted proposition is assuredly not always
of equal evidence with that which we had to convert, while, at the same time,
we are not so well accustomed to it; for example, the proposition, Some stones
attract iron, every one will admit, because The mat/net is a alone, and attracls
iron. This syllogism is in the Third Figure. In the first, by conversion of
one of its premises, it would run thus :
Major, — AU magnets attract iron ;
Minor, — Some stones are magnets ;
Conclu,sioii, — Some xUmes attract iron.
OHere we arc unaccustomed to the minor proposition, while it appears as if wc
4DUSt pass all stones under review, in order to pick out magnets from among
them. On the other hand, that the magnet is a stone, is a proposition which
far more naturally suggests itself, and demands no consideration. In like man-
..ner, A circle is not a rquare ; for Oie circle is round, the square not. This proof
i[in the third figure] is as follows, when cast in the first :
What is not round is no circle ;
A square is not round ; «
Consequently, etc.
Here the major proposition is converted by means of terminus injinitus, and its
truth is manifested to us only tlirough the consciousness that «// circles are
round. For, indepeuviently of this proposition, should we not hesitate — there
being innumerable things which are 730/ round — whether the circle were one
of those which belonged to this category? We thmk not; because we are
aware.
§ 231. "It is thus apparent that we use every syllogistic figure there, where
the propositions, as each figure requires them, are more familiar and more rur-
rcnt. The difference of figures rests, therefore, not only on their form, but
extends itself, by relation to their employment, also to things themselves, so
that we use each figure where its use is more natural : The first for finding out
9r proving the Attributes of a thing ; the .second for finding out or proving the
Difference of things ; the third for finding out and proving Examples and Ex-
ertions ; the fourth for finding out and excluding the Species of a Genus.
APPEliFDIX. 645'
§ 232. " Further, whether the three last 5gures are less evident than the
first, is a question which has been denied [affirmed (?)] on this account, that
the first figure only rests immediately on the Dictum <le Omni et Nullo [§ 220]
whilst the others have hitherto, by a circuit, been educed therefrom. We havfir
already remarked [§ 211] that this circuit, through our mode of notation, is
whblly superseded. We need, therefore, only translate its principle into the
vernacular, and we shall find that the Dictum de Omni et Nullo is on that
account applicable to the first figure, because its truth is based on the nature
of the proposition. From this principle, therefore, the first figure and it*
moods admit of an immediate deduction ; it is thus only a question whether the
other figures are incapable [capable (?)] of such immediate deduction, or
whether it is necessary previously to derive them through the first figure. Our
mode of notation shows that the latter is an [unnecessary] circuit, because
every variety of syllogism admits for itself a various notation, and because, iri
that case, the premises are taken for what they actually are. Consequently,
every figure, like the first, has its own probation, — a probation drawn exclu-
sively from the natures of the propositions. The whole matter is reduced to
this : — Whether a notion, wholly or in part, is, or, toholly or in part, is not, under
a second : and whether, again, this second, wholly or in part, is, or, wholly or in
part, is not, under a third. All else proceeds only on the interchange of equiv^
alent modes of expression, — the figured, namely, and those which are not
figured. And this interchange we maj' style translating, since the figurecf
modes of expression may be regarded as a special language, serving the pur-
pose of a notation. We have above (§ 220), after all the syllogistic mood's
were discovered and denoted, adduced the Dictum de Omni et Nullo, but only
historically, since our manner of determining the syllogistic moods is immedii-
ately founded on the nature of the propositions, from which this Dictum is only
a consequence. Moreover, this eonseciuence is special, resting, as it does, oni
the notions of Species and Genera. Wherefore, its validity only extends so far
as propositions can be recalled to these notions; as, for example, in the First
Fignre. In the Second, the notion of Difference emerges ; and in the Third,
the notion of Example. If we, therefore, would have special dicta for the
several Figures, in that case it would follow, and, at the same time, become
manifest tliat the middle term of a syllogism, considered for itself, expresses, in
the First Figure, a principle \of Ascription or Procreation'] ; in the Second,
Difference ; in the Third, an Example ; and in the Fourth, the principle o(
Reciprocity.
'* 1. For the First Figure. Dictum de Omni et Nullo. What is true of all A,
is true of every A.
'^ 2. For the Second Figure. Dictum de Diverse. Things which are different,
are not attributes of each other.
" S. For the Third Figure. Dictum de Exemplo. When we find things A
which are B, in that case some A are B.
" 4. For the Fourth Figure. Dictum de Reciproco. I. If no M is B, then no
B is this or that M. IT. If C is [or is not] this or that B, in that case some B
are [or are not] C."
646
APPENDIX.
(I) PLATTER.
Platner, Philosophische Aphorismen, 3d ed., 1 793. — Part I., § 544, conformed
to his Lehrbuch der Logik und Metaphyslk, 1795, § 227. " The reason why the
predicate belongs to the subject is in all possible syllogisms this, — because the
subject stands in a relation of subordination with [is either higher or lower
than] a third notion to which the predicate belongs. Consequently, all infer-
ence proceeds on the following rule : If the subject of the [concluding} judg-
ment stand in a relation of subordination with a third notion, to which a certain
predicate pertains ; in that case, this predicate also pertains to the same judg-
ment, affirmatively or negatively."
In his note on this Aphorism, Platner (Lehrbuch) admits — " My funda-
mental rule is only at fault in the second Aristotelic figure, which, however, is
no genuine figure ; because here, in the premises, the subject and predicate
have changed places," etc. In the 2d edition of his Aphormns (1784) he had
adopted the principle of Identity with the same third, as he has it : " In what
exLen.sion or proportion (Mousse) two notions are like or unlike to a third, in the
same extension or proportion are they like or unlike each other." (§ G28.)
Philosophische Aphonsmen, Part I., third edition, 1 793, § 568, compared with
second, 1 784, § 672-676. — " Nevertheless, each of these grammatical figures of
syllogism has its peculiar adaptation in language for the dialectical application
of proofs ; and the assertion is without foundation that the first is the most
natural. Its use is only more appropriate, when we intend to show — that a
predicate pertains [or does not pertainl^ to a subject in virtue of its class. More
naturally than the first do we show, in the second, the difference of things
apparently similar : and in the third, the similarity of apparently different things.
Tlie fourth figuie [it is said in the second edition], on account of the position
of its terms, is always unnatural in language."
Philosophische Aphorismen, Part I., last edition, 1 793, § 561. — " The principle
of the first figure is the Dictum de Omni et Nullo."
§ 564. -^" Touching the other figure [the third, for in this edition Platner
abolishes, in a logical relation, the second], its special principle is the following
rule : — What belongs to the subordinate, thai, since the subordinate is apart of the
universal, belongs also in part (particularly) to the universal."
In the second edition, 1784, the second figure is recognized, and, with the
third, obtains its special law.
§ 659. — " The principle of the second figure is : — If two notion.<t, wholly or
in part, are opposite to a third, so are they also, wholly or in part, opposite to each
other."
§ 664. — " The principle of the third figure is : — What can be particularly
affirmed or denied of a sulxdtem species, that also, in so far as such subaltern
species is part of a genus, may be particularly affirmed or denied of the genus."
Philosophische Aphorismen. Part I., § 546. Note. — "In general, logicians
treat the subject as if it were necessarily subordinated to the predicate. It
may, however, on the contrary, be the higher notion, and the predicate thus be
subordinated to it. This i.s the case in all particular propositions where the
predicate is not an attribute of the genus, but an accident of the subject. For
instance, — Some creatures are animals ; here the subject is the higher : Some
APPENDIX. 64T
men are imperfect ; here the higher is the predicate. We must not, therefore,
in our syllogistic, thus enounce the fundamental rule of reasonings, — If the
suhject he subordinated to a third notion, but with or in the relation of subordina-
tion with a third notion."
(m) - FRIES.
Fries, System, der Logik, § 56. — " The species of categorical syllogisms are
determined by the variety of relations in which three notions may stand to each
other, so that a syllogism may be the result.
" These relations may be thought as three.
" Case I. — Three notations are reciprocally subordinated in gradation, so
that the second is subordinated to the first, but superordinated to the third.
" Case II. — Two notions are subordinated to a third.
" Case III. — Two notions are superordinated to a third.*
" When, in these cases, is a syllogism possible ?
§ 57. — "In all the three cases the syllogisms are equally valid, for they are
founded on the general laws of the connection of notions.
" They all follow, to wit, from the relation of a whole sphere to its parts,
which lies in the Dictum de Omni et Nullo. The principles for the three men-
tioned cases are thus :
" For the first, — The part (C) of the part (B) lies in the tvliole (A), and what
(A) lies out of the whole (B), lies also out of its parts (C).
" For the second, — What (A or some A) lies out of the whole (B), lies also
out of its parts (C).
"For the third, — Jf a part (B) lies in two wholes (A and C), in that case
these have a pari in common ; and if a part (B) lie in a ivhole (C), but out of
another tchole (A), in that case the first (C) has a part out of the other (A).
"The fiist case alone coincides immediately with the perfect declaration
of a syllogism, — that a case is therein determined by a rule. For the third
case, therefore, our two declarations of a major premise — that it is the ride,
and that it contains the major term — do not coincide, seeing that here the
minor term may be forthcoming in the rule. On this account the arrangement
of the first case is said to be the only regular, and the others are reduced to it.
That this reduction is easily possible, we may in general convince ourselves, by
reflecting that every syllogism requires a general rule as premise, and that the
other cases are only distinguished from the first by a converted arrangement
of the propositions. But as all propositions may be either purely converted or
purely counterposed, consequently the two last cases can at most so far deviate
from the first that they are connected with the first case only through reversed
((jegentheilige) notions.
§ 57 b. — " The doctrine of the several species of categorical syllogisms, as
regulated by the forms of their judgments, is at bottom an empty subtlety ;
for the result of all this circuity is^only that, in every categorical syllogism,
a case is determined by a rule, and this is already given in the law, that
in every reasoning one premise must be universal. The scholastic logic
treats of this doctrine only in so far as the species of syllogism are determined
by the forms of judgment, and thereby only involves itself in long grammati-
1 [See Jordano Bruno (in Denzinger, Logik, t. ii. p. 269). Stattler, Logica, J 237, p. 163.]
648 APPENDIX.
cal discussions. Aristotle has been falsely reproached for overlooking the
fourth figure, he only having admitted three. For Aristotle proceeds, pre-
cisely as I have here done, only on the relation of notions in a syllogism, of
which there are possibly only our three cases. His error lies in this, — that
he did not lay a general rule at the root of fevery figure, but, with a prolixity
wholly useless, in determining the moods of the several figures, details each,
even of the illegitimate, and demonstrates its illegitimacy. This prolixity has
been too often imitated by other logicians, in the attempts at an evolution
of the moods. Kant goes too far in denouncing this whole doctrine as a
mere grammatical subtlety. The distinction of the three cases is, however,
a logical distinction ; and his assertion that the force of inference in the other
two is wholly derived from that of the first case, is likewise not correct. I
manifestly, however, conclude as easily in the third case, — ' A part which lies
in two wholes is a part common to both,' — as in the first, — ' The part of the
part lies in the whole.' The third case presents, indeed, the readiest arrange-
ment for reasonings from the particular to the general, i. e., for syllogisms in
the second figure according to our terminologj'.
" The scholastic doctrine of the four syllogistic figures and nineteen moods
of categorical syllogisms requires no lengthened illustration. If the figures are
determined by the arrangement of notions in the premises, then the following
combination is exhaustive. For the conclusion in all cases S P [being
supposed the same], the [terms or] notions stand :
1 ) According to our first case, M P
S M
2) With converted mi^or premise, P M
S M
3) With converted minor premise, M P
M S
4) Both premises converted, P M
M S
" Should we therefore simply convert both premises in a syllogism of the
first figure, we are able to express it in all the figures. Let the notions given
be ^reproof, lead, metal, there then follows the conclusion — Some met(d is n(H
^reproof — from the premises :
In the First Figure — No lead is fireproof ;
Some metal is lead ;
In the Second Figure — Nothing fireproof is lead ;
Some metal is lead ;
In the Third Figure — No iead is fireproof ;
All lead is metal ;
In the Fourth Figure — Nothing fireproof is lead;
All lead is metal.
" It is here apparent that the first three figures are our three cases ; but the
APPENDIX. 649
fourfti we did not employ, as it contains no peculiar relations or notions, but
only under our first case superordinates, and then subordinates a middle term.
This manner of enunciating a syllogism is thus only possible where we are
competent, through conversions, to transmute the arrangement of the first
figure into that of the fourth. Now this happens : 1] If we convert the conclu-
sion S P into P— S, since then the major arid the minor terms, as
also the major and minor premises, change names ; or, 2] If both premises
allow of an immediate conversion, so that the one remains universal ; for then
the converted propositions contain the same thoughts as those given, and,
consequently, establish the same conclusion."
[Objections to Fries' doctrine of figure — 1°, Only applies to affirmatives;
2°, Only the arrangement of the results of a successful comparison, and takes
no heed of the comparison that may have been fruitless (the illegitimate
moods) ; 3°, Takes account of only one subordination, for, in the second and
third cases, in each there is a reciprocal subordination in Extension and Coni-
prehension.]
Cnatido) KRUG ASD BENEKE- THEIR DOCTRIJfES OF SYLLOGISM CRITICIZED.
The authority of the two following philosophers, who conclude this series, is
rather negative than positive ; inasmuch as they both concur in proving that
the last attempts at a reformation of the Syllogistic Theory proceed on a
wholly different ground from that on which, I think, this alone can be accom-
plished. These two philosophers are Krug and Beneke ; for, beside them, I
am aware of no others by whom this has been attempted.
Krug was a disciple of the Kantian school, Kant's immediate successor in
his Chair of Logic and Metaphysics at Koenigsberg, and, subsequently, Pro-
fessor of Philosophy in the University of Leipsic. He is distinguished not
only as a voluminous writer, but as a perspicuous and acute thinker ; and his
peculiar modification of the Kantian system, through a virtual return to the
principle of Common Sense, is known among the German theories by the
name of Sj/nthefism. His Logic (the first part of his System of Theoretical
Philosophy) was published in 1806, and is one of the best among the many
excellent treatises on that science which we owe to the learning and ability of
the Germans. (I have before me the fourth edition, that of 1833.) Krug
propounded a new theory of S}-llogistic ; but the novelty of his scheme is
wholly external, and adds only fresh complication to the old confusion. It has,
accoi'dingly, found no favor among subsequent logicians.
Passing over the perverse ingenuity of the principles on which the whole
doctrine is founded, it is enough to state that Krug distributes the syllogistic
moods into eight classes. Of these, the first (which, with some other logicians,
he considers not as a figure at all, but as the pure, regular, and ordinary form
of reasoning) corresponds to the First Figurie of the Aristotelico-Scholasti(^
distribution. The other seven classes, as so many impure, irregular, and ex-
traordinary forms, constitute (on the analogy of Rhetoric and Grammar) so'
many figures. Of these, the new is only the old First Figure, the minor
premise, in extension, being stated before the major. Krug, like our other
modern logicians, is not aware that this was the order in which the syllogism
82
650 APPENDIX.
was regularly cast, in common language, by the Greeks, by the Arabians, b/
the Jews, and by the Latins prior to Boethius.^ The old and new first figures
are only a single figure, the syllogism being drawn in the counter orders of
breadth and of depth. A mood in these orders, though externally varying, is
intrinsically, is schematically, the same. Krug's distinction of his new first
figure is, therefore, null. Thus, Barama is Barbara ; Caieme is Celarent ;
Dirami is Darii ; Firemo is Ferio. Nor is his discrimination of the other six
better founded. His new (the old) Second and his Fifth Figures are also one.
The latter is precisely the same with the former ; Fimeso is Festino, and Fomaco
is Baroco. In one case (under Camestres), Krug adopts, as alone right, the
conclusion rejected by the logicians. In this, he and they are, in fact, both
wrong, though in opposite ways. Each mood, in the second (as in the third)
figure, has two indifferent conclusions ; and the special one-sided practice of
the former is only useful as gainsaying the general one-sided precept of the
latter. The same objection applies to Krug's new (the old) Third, in connec-
tion with his Sixth Figure. They are one ; Daroco is Bocardo, Fapimo is
Felapton, and Fisemo is Ferison. In two cases (under Disamis and Bocardo)
Krug has recognized the repudiated conclusion. Krug (§ 109) has, however,
committed an error in regard to Bocardo. He gives, as its example, the
following syllogism, in which, for brevity, I have filled up the quantifications :
"Swne animals are not [any] viviparous ;
AU animals are [some] organized things ;
Therefore, some organized things are not [any] viviparous."
In a note, he adds, " The conclusion should here be : — ' Therefore, some
things which are not viviparous are (some) organized.' And this is seen also by
reduction. We have, however, followed the arbitrary precept of the logicians,
that the extreme in the second proposition should stand subject in the conclu-
sion ; although it be here indifferent which extreme becomes the subject. The
conclusion is only changed into another quality." Only changed into another
quality ! Only an affirmative conclusion from a negative premise ! The
legitimate inference is :
" Therefore, no viviparous is some organic ; " or,
" Therefore, any viviparous is not some organic."
Bachmann (Logik, § 135), another eminent logician, has erred with Krug.
A particular predicate in a negative proposition seems indeed one of the last
difficulties for reformed logic. Krug's new (the old) Fourth Figure bears a
corresponding relation to his Seventh. He is right, certainly, in abolishing all
the moods of the fourth figure except Fesapo and Fresiso ; and, from his point
of view, he is hardly to be blamed for not abolishing these likewise, along with
the correlative moods Fapesmo and Frisesmo, and, with them, his seventh
figure. Finally, rejecting the scholastic doctrine of Reduction, he adopts, not
without sundry p.^rverse additions, Kant's plan of accomplishing the same end;
ao that Krug's conversive and contrapositive and transpositive interpolations,
1 See p. 625. — Ed.
APPENDIX. 651
by which he brings back to propriety his sevenfold figured aberrations, are
merely the substitution of one " false subtlety " for another. He, and Bach-
mann after him, renounce, however, " the crotchet of the Aristotelians," in
making the extreme of the prior premise the predicate, always, of the conclu-
sion, in the first and second figures ; and, though both do this partially and
from an erroneous point of view, their enunciation, such as it is, is still
something.
Professor Beneke, of Berlin, is the last to whom I can refer, and in him we
have, on the point in question, the final result of modern speculation. This
acute and very original metaphysician stands the uncompromising champion
of the philosophy of experience, against the counter doctrine of transcenden-
talism, in all its forms, now prevalent in Germany ; and, among the other de-
partments of mental science, he has cultivated the theory of reasoning with
great ability and success. In 1832 appeared his Lehrbuch der Logik, etc.; in
1839, his Syllogismorum Analyticorum Origines et Ordo Natnralis, etc. ; and in
1842, his System der Logik, etc., in two volumes. In Logic, Beneke has devoted
an especial share of attention to the theory and distribution of Syllogism ; but
it is precisely on this point, though always admiitng the ingenuity of his reason-
ings, that I am compelled overtly to dissent from his conclusions.
The Syllogistic of Beneke is at once opposed, and correspondent, to that
of Krug; there is an external difference, but, without imitation, an internal
similarity. Instead of erroneously multiplying the syllogistic figures, like the
Leipsic philosopher, the philosopher of Berlin ostensibly supersedes them
altogether. Yet, when considered in essence and result, both theories agree
in being, and from the same side, severally, the one an amplification, the other
an express doubling, of the nineteen scholastic moods. In this, both logicians
were unaware that the same had been long ago virtually accomplished in the
progress of the science ; neither considered that the amplification he proposed
was superficial, not to say mistaken ; and that, instead of simplicity, it only
tended to introduce an additional perplexity into the study. Beneke has the
merit of more openly relieving the opposition of Breadth and Depth, in the
construction of the syllogism ; and Krug, though on erroneous grounds, that
of partially renouncing the old error of the logicians in regard to the one
syllogistic conclusion, in the second and third figures. But, in his doctrine of
moods, Beneke has, I think, gone wrong in two opposite ways : like Krug, in
his arbitrary multiplication of these forms ; like logicians in general, in their
arbitrary limitation.
In regard to the former — the counter quantities of breadth and depth do not
discriminate two moods, but merely two ways of stating the same mood. Ac-
cordingly, we do not multiply the moods of the first figure, to which alone the
principle apphes, by casting them in the one dependency and in the other; we
only show that, in that figure, every single mood may be enounced in a two-
fold order, more german, the one to the quantity of extension, the other to the
quantity of intension. An adequate notation ought, equally and at once, to
indicate both. But in reference to the second and third figures, the case is
worse. For in them we have no such dependency at all between the ex-
tremes ; and to double their moods, on this principle, we must take, divide, and
^^^ APfEJTD'rx.
arbitrarily appropriate, one of the two indifferent conclusions. But, as evetj
single liibod of these figures has a double conclusion, this division cannot be
made to difference their plurality. If Professor Bencke would look (instar
omnium) into Apuleius or Isidorus, or, better than either, into Blemmidas, he
will find all his new moods (not, of course, those in the fourth figure) stated by
these, as by other ancient logicians; who, however, dreamed Aot that the mere
accidental difference of, Avhat they called, an analrjtic and synthetic enounce-
ment, determined any multiplication of the moods themselves.
In the latter respect. Dr. Beneke has only followed his predecessors ; I, there-
fore, make no comment on the imperfection. But, in accomplishing what he
specially proposes, whilst we do not find any advancement of the science, we
find the old confusion and intricacy replaced by another, perhaps worse. To
say nothing of his non-abolition of the fourth figure, and of his positive
failures in doubling its moods, the whole process is carried on by a series of
arbitrary technical operations, to supersede which must be the aim of any one
who would reconcile Logic with nature. His new (but which in reality are
old) amplifications are brought to bear (I translate his titles) through " Com-
mutations of the Premises, — J)y Subalternation, — by Conversion, — by Con-
traposition ; " and " of the Major, — of the Minor," — in fact, of both premises
(e. g., Fesapo, etc.). And so diflicult are these processes, if not so uncertain
the author's language, that, after considerable study, I am still in doubt of his
meaning on more points than one. I am unable, for example, to reconcile the
following statements : — Dr. Beneke repeatedly denies, in conformity with the
common doctrine, the universal quantification of the predicate in aflSrmative
propositions; and yet founds four moods upon this very quantification, in the
conversion' of a universal affirmative. This is one insolubility. But there
arises another from these moods themselves (§ 28-31). For, if we employ this
(juantific-ation, we have moods certainly, but not of the same figure with their
nominal correlatives; whereas, if we do not, simply rejecting the permission,
all slides smoothly, — we have the right moods in the right figure. This, again,
I am unable to solve. Dr. Beneke's duplication of the moods is also in sundry
cases only nominal ; as is seen, for example, in Ferio 2, Fesapo 2, and Fre-
siso 2, which are forms, all, and in all respects, identical. I must protest also
against his violence to logical language. Thus, he employs everywhere " non
orane^" " non omnia," "alle sind nicht," etc., which is only a particular (being
a mere denial of omnitude), for the absolute or universal negative, " nullum,**
" nulla," " kein ist," tio, none, not any, etc., in opposition both to principle and
to tlie practice of Aristotle and succeeding logicians.
(p) TITJUS.
Gottlieb Gerhard Titius, Ars Cogitandi, sice Scientia Cogitationum Cogitan-
tiuni, C'ofjifdtionibus Necesaaris tfistructa et a Peregrinis Liberata. Leipsiae,
r723 (first edition, 1701).
Titius h.as been partially referred to, by Sir W. Hamihon, &s' having main-
tained the doctrine of a Quantified Predicate. See above, p. 555. His theory
of the Figure and Mood of Syllogism is well deserving of notice, — proceed-
ing, as it does, on the application of that doctrine. This theory is principally
APPENDIX. 668
contained in the following extracts from his Ars Cogitandi, which show how
closely he has approximated, on several fundamental points, to the doctrines
of the New Analytic.^
Titius gives two canons of syllogism :
I. AfBrmative. " Quaecunque conveniunt in uno tertio, ilia etiam, juxta
mensuram illius convenientiae, inter se conveniunt."
II. Negative. " Quaecunque pugnant in certo aliquo tertio, ilia, juxta men-
suram illius disconvenientiae, etiam inter se pugnant." C. ix. §§ 30, 27.
The following relates to his doctrine of Figure and Mood, and to the special
rules 6f Syllogism, as commonly accepted :
C. X. § i. " Sic igitur omnium Syllogismorum formalis ratio in genuina medii
termini et praedicati ac subjecti Conelusionis collatione consistit ; cam si dicere
velis formam essentialem aut Jiguram generalem, vel communem, non valde
reluctabor.
§ ii. " Praeter earn vero Peripatetici Figuras ex peculiari medii termini situ
adstruunt, ea ratione ut Primam figuram dicant, in qua medius terminus in
Majore est subjectum, in Minore Praedicatum, Secundam, ubi idem bis praedi-
cati, et Tertiam, ubi subjecti locum bis subit. Galenus adjecit Quarlam primae
contrariam, in qua medius terminus in majore est praedicatum, In minore sub-
jectum, quam plurlbus etiam exposuit Autor. Ai't. Cog. p. 3, c. 8.
§ lil. " Caeterum illae figurae tantum sunt accidentales, ab iisque vis conclu-
dendi non dependet. Qiiodsi tamen quis diversum medii termini situra atten-
dendum esse putet, turn noc Quarta figura negligenda esse videtur, licet earn
Peripatetici nonnulli haut curandam existiment, vide Ulman. Synops. Log. 1. 3,
c 2, p. 164.
§ iv. " Interim Prima caeteris magis naturalls ex eo vlderi potest, quod Sub-
jectum et Praedicatum Conelusionis in Praemlssis suam retineat qualitatem, cum
in secunda et terlia alterum qualitatem suam exuere, in quarta vero utrumque
eam deponere debeat
§ v. " Postea in unaquaque figura, pro ratione quantitatis et qualitatis propo-
sitlonum, peculiares Modi adstruuntur, ita quidem ut Primae figurae Quatuor,
totidem Secundae, Tertiae sex attribuantur, ex quibus etiam deblte variatis
Quarta quinque acclpiat, prout ilia passim cum vocabulis memorlalibus recen-
serl solent, ut Ilia quidem hue transcribere opus non sit, vide Autor, Art. Cogit.,
p. 3, c. 5, 6, 7, 8.
§ vi. " Non opus esse istis figuris et modls ad dijudicandam Syllogismorum
bonitatem, e.x monito § 3, jam Intelllgi potest. Quomodo tamen sine iis bonitas
laudata intelligi queat, Id forte non adeo lujuidum est
§ vll. " Non diu hie quasrenda sunt remedia : Observetur forma essentialis
seu figura communis, ac de verltate Syllogismi recte judicabitur. Applicatio
autem hujus moniti non est difficilis, nam primo respiciendum ad conclusionem,
deinde ad medium terminum, quo facto etiam judicari potest, an ejus et ter-
minorum conduslonis collatio in praemlssis recte sit instituta nee ne. . . .
§ ix. " De caetero uti anxie jam non inquiram, an omnis bene concludendi
1 For Titius" doctrine of a Quantified Tred- rropositions and to the Hypothetical Syllo-
icate, its application to the Conversion of gism, see above, pp. 555, 527, 603. — Ed.
654
APPENDIX.
ratio numero modorum denario circumscribatur, quod quidera juxta htpi^^uof
tnathematicam detnonstrasse videri vult Autor. Ar(. Coy. p. 3, c. 4, ita id haut
admiserim, quod illi modL quos vulgo laudant,- Primae, Secundae aut Tertia;
figurae praecise sint assignandi, licet hoc itidem acucnine mathematieo se demon-
strasse putet dictus Autor. d. I. c. 5 seqq.
§ X. " Cum enim quaevis propositio possit converti, modo quantitas praedicati
probe observetur, hinc necessario sequitur, quod quivis Syllogismus, adhibita
propositionum conversione, in quavis figura possit proponi, ex quo non potest
non fequalis modorum numerus in unaquaquc figura oriri, licet illi non ejusdem
semper sint quantitatis. '
§ xi. " Operae pretium non est prolixe per omnia Syllogismorum singulis
figuris adscriptorum exempla ire, sufficiat uno assertionem illustrasse, v. gr. in
prima figura, modo Barbara hie occurrit Syllogismus apud d. Autor. c. 6.
0. sapiens tubjicitur voluntati Dei,
0. honestits est sapiens,
E. 0. konesbu subjicUur voluntati Dei.
§ xii. " Hunc in secunda figura ita proponere licet :
Quidam, qui subjicitur voluntati Dei, est omnis sapiens,
Omnis honestus est sapiens,
E. omnis honestus subjicitur voluntati Dei,
ratio concludendi manet eadem, sapiens enim ct is qui subjicitur voluntati Dei,
uniuntur in Majore, dein sapiens el honestus in Minore, ergo in conclusione idea
Mpientis et Ejus qui voluntati Dei subjicitur, quoque conveniunt
§ xiii. " In tertia figura ita so habebit :
0. sapiens subjicitur voluntati Dei,
Q. sapiens est omnis honestus,
E. 0. honestus subjicitur voluntati Dei,
nee in hac concludendi ratione aliquid desiderari potest, nam medius terminus
univcrsaliter unitur cum conclusionis praedicato, deinde, quantum sufficit, con-
jungitur cum ejusdem subjecto, seu oinni honesto, ergo subjectum et praedicatum
se quoque mutuo admittent.
. § xiv. " Cajterorum eadem est ratio, quod facile ostendi posset, nisi tricas illas
vel scribere vel legere tacdiosum foret. Ex his autem sequitur, quod omnes
regulcE speciales, quce modis vulgaribus attemperaXcB vulgo circumferuntur, falsce
sint, quod speciatim ostcndere liceat.
§ XV. " In universum triplici modo impingitur, vel enim conclusio creditur
absurda, quce talis non est, vel vitiwn est in materia, ac altera pj-cemi^sarum falsa,
vel aiisunt quatuor termini, adeoquc absurditas conclusionis, si aliqua subest,
nunciuam ab ea causa dependct, quam refertint rcgulae.
§ xvi. " Sed videamus distinctius (1) major in prima Jigura semper sit univer^
salis
APPENDIX. 655
§ xvii. " Inflectam hue exemplum minus controversum, quod Autor, Art. Cog.
p. 3, c. 7, in modo Dlsami^, tertise figurae, proponit :
Quidam impii in honore habentur in mundo,
Quidam vituperandi sunt omnes impii,
E. quidam vituperandi in honore habentur in mundo.
§ xviii. " Hie habes primam figuram cum majore partieularl, optime iterum
concludentem, nam licet medius terminus partieulariter sumatur in majore,
ejus tamen ille est capacitatis, ut in eodcm cbnvenientia prsedicati et subject!
ostendi queat, et nisi hoc esset, nee in tertia figura rite concluderetur.
§ xix. " Nee valde obsunt, quae vulgo illustrandae regulaj adducuntur. Ex
sententia Weis. in Log. p. 1, lib. 2, c. 2, § 4, male ita concluditur:
Q. animal volat,
O. leo est animal,
E. Q. leo volat.
Verum si animal sumitur in minore sicut in majore, turn ilia falsa est, si vero
alio sensu, tum existunt quatuor termini ; his ergo causis, non particularitati
Majoris, vitiosa conclusio tribuenda.
§ XX. " Nam alias ita bene concluditur :
Q. animal volat,
O. aids est animal (illad qnoddam),
JE. O. avis mlat,
nam licet medius terminus particularis sit, tantas tamen est latitudinis, ut cum
utroque Conclusionis termino possit uniri.
§ xxi. " Porro (2) Minor semper sit affirmans. Sed quid desiderari potest
in hoc Syllogismo :
O. homo est animal rationale,
Leo non est homo,
E. non est animal rationale?
et nonne ilia ratio concludendi manifeste bona est, quae subjectum et praedi-
catum, qu£e in certo tertio non conveniunt, inter se quoque pugnare contendit ?
§ xxii. '' Sed ais, mutemus paululum Syllogismum et absurditas conclusionis
erit manifesta :
O. homo est animal,
Leo non est homo,
E. leo non est animal !
Verum si terminus animalis in Conclusione perinde sumitur, sicut suppositus
fuit in majore, nempe partieulariter, tum conclusio est verissima ; si autem aliter
accipiatur, tum evadunt quatuor termini, quibus adeo, non negation! Minoris,
656 APPENDIX,
absurditas conclusionis est imputanda, quse observatio in omnibus exemplls quae
hie objici possunt et solent, locum habet.
§ xxvlil. " Sed revertamur ad regulas vulgares ! Nimirum (3) In secunda
figura major sit universalis. Verum cur non ita liceat concludere :
Quidam dives est Saxo,
Quidam Germanus est omnis Saxo,
E. quidam Germanus est dives?
quod argumentum Weis. 1. 2, c. 4, § 2, intuitu tertiaB figurae proponit.
§ xxix. " Argumenta, quaB fallere videntur, v. gr. quod Weisius 1. 2, c. 3, § 8,
profert :
Quidam homo est sapiens,
Nidlus slultus est sapiens,
E. nullus stidtus est homo,
et similia, responsione, § 22, data eliduntur; nimirum conclusio vel non est
absurda, si recte intelligatur, vel adsunt quatuor termini, quibus adeo, non
pavticularitati majoris, vitium est imputandum.
§ XXX. " Amplius (4) Ex puris affirmative^ in secunda Jigura nihil concludiiur,
sed mirum foret, si ilia concludendi ratio falleret, quse fundamentum omnium
Syllogismorum affirmativorum tam evidenter prae se fert ! Hoc argumentum
utique formaliter bonum est :
Omnis sapiens sua sorte est contentus,
Faulus sria sorte est contentus,
E. Faulus est sapiens.
I
§ xxxi. "Sed fallunt multa argumenta, v. gr. Weisio </. c. 3, § 3, adductum:
Omnis lepus vivit,
Tu vivis,
E. tu et lepus,
verum non fallunt ob affimiationem praemissarum, sed quia vel minor falsa est,
si scil. praedicatum accipiatur eodem sensu, quo in Majore sumtum est, vel
quia adsunt quatuor termini, si praedicatum Minoris particulariter et alio eensu
accipiatur.
§ xxxii. *' Non possunt etiam vulgo diffiteri, quin ex puris s^rmativis ali-
([uando quid sequatur, verum id non vi/orwice sed matericB fieri causantur, vide
Ulman. Log. 1. 3, c. 3, § 4. Haec vero est petitio prinoipii, nam quas conveniunt
in uno tertio, ilia etiam inter se convenire debent, idque non fortuito, sed
virtute unionis laudats?, seu beneficio formae.
§ xxxiv. "In tertia figura (5) Minor semper sit affirmans. Ego tamen sic
jrecte concludi posse arbitror •
^ APPENDIX. 657
Quoddam laudnndum est omm's vhius,
Nullum laudandum est qwedain magnificentia,
E. qucedam magnificentia non est virtus.
§ XXXV. " Nee valde urgent exempla opposita AVeisIus d. 1. 2, c. 4, § 2, hoc
affert :
Oinnis homo amhulat,
Nullus homo est parens,
E. quidam porous non amhulat,
nam recurrit responsio § 22 data, quae vel conclusionera falsam non esse, vel
causam falsitatis a quatuor terminis dependere ostendit, quse etiam locum ha-
beret, licet conclusionem universalem, Nidlus porcus amhulat, assumas.
§ xxxvi. " Tandem (G) In tertia Jigura conclusio semper sit particularis.
Verum Syllogismum cum conclusione universali,jam exhibui § 13, in Exemplis
autem quae vulgo afferuntur, v. gr.
Omnis saiator est honoraius,
Om.nis senator est homo (quidam scil.),
E. omnis homo est honoratus,
vide Weis. d. I. 2, c. 4, § 3, occurrunt quatuor termini (nam homo, in minore-
particulariter, in conclusione universaliter sumitur), qui adeo veram absurdae-
conclusioiiis causam, ac simul regulae vulgaris falsitatem ostendunt.
§ xxxvii. " Ilia autem omnia, quae contra vulgares regulas hactenus dispiita-
vimus, non oo pertinent, quasi rationem concludendi rejiciendis regulis hinc
inde confectam commendemus, ita ut in demonstrationibus eadem uti, aut valde
delectari debeamus. Quin omni potius eo spectant, ut Peripateticos, qui for-
mam Syllogismorum essentialem vel omnino non vel nimis frigide exponunt, in
explicandis etiam eorum figuris accidentalibus, falli prpbarem.
§ xxxix. " Atque ex hactenus dictis etiam intelligi potest, quas nostra de-
Reductione sit sententia. Nimirum ex nostris hypothesibus ilia nihil aliud est,
quara Syllogismorum per omnes quatuor Jiguras accidentales, salva semper con-
clusione y facta variatio.
§ xl. '• Pertinet igitur ilia tantum ad Prcemissa, Syllogismus enim semper ut
instrumentum veritatis inquirendae considerari, adeoque quaestio probanda,,
(juae semper immobilis sit, nee, prout visum est, varietur, przesupponi debet.
§ xli. " Rcductionis unica Lex est, ut simpliciter, juxta figura; indolem, prop-
ositiones convertamus, quod sine uUa difficultate procedit, dummodo quanti-
tatem subjecti et praedicati debite confideremus, ceu ex iis quae de Conversione
diximus satis liquet.
§ xlii. "Finis est, ut pe'r ejusmodi variationem, terminorum unionem vel'
separationem eo accuratius intelligamus, hinc omnis utilitas reductioni non est
abjudicanda, si enim recte instituatur, ingenium quantitati propositionum
observandae magis mj^Sque assuescit, ac inde etiam in penitiorem formae essen-
tialis intelligentiam provehitur.
83
658
APPEI^DIX.
§ xHii. "In vulgari Reductione, quae in libelHs logicis passim exponitur, vide
Aut. Art. Cog. p. 3, c. 9, quaedem exempla reprehendi non debent, quando
V. g. Cesare ad Celarent reducitur, nam ibi simplici conversione alicujus propo
sitionis defunguntur, juxta legem, quam § 41, reductioni dedimus.
§ xliv> " Sed si ab illis exemplis abeas, parum vel nihil est, quod in eadem
laudari debeat, dum fere ex falsis hypothesibus omnis reductio oritur, nam
conversio per contraposhionem priesupponitur, quam tamen valde dubiam esse,
.supra ostendiraus, prajterea peculiares modi in singulis figuris adstruuntur, ao
omnis reductio ad primam Jiguram facienda esse existimatur, cum tamen idem
Syllogismus per omnes figuras variari queat.
§ xlv. " Ipsa vero reductio nullis legibus adstricta est, oonvertitur Con-
c-lusio, transponuntur Praemissae, propositiones negativae mutantur in affirma-
livas, atque ita quidvis tentatur, modo figura intenta oblineatur. Quo ipso
puerilis error, quo Logica, pro arte concinnandi tres lineas, easque in varias
formas mutandi habetur satis elucet. Inepta scientia est, quae in verbis dispo-
ncndis, circumagendis aut torquendis unice, occupatur.
§ xlvi. " Juxta haec igitur, vulgari modo reducere, maximam partem nihil
aliud est, quam errorem errore tegere, ingenia discentium torquere, ac magno
conatu magnas nugas agere, inscitiamque professa opera ostendere." — Ed.]
IV. — Syllogistic Moods.
(p. 285.)
I. — DIRECT AND INDIRECT MOODS.
(a) TliEIR PRmClPLE.- FIRST AND FOURTH FIGURE.
(Seep. 302.)
Direct and Indirect Moods — principle of. — That the two terms should
hold the same relation to each other in the conclusion that they generally hold
to the middle term in the premises. This determined by the Question. This
constitutes direct, immediate, natural, orderly inference. When reversed, by-
conversion, there emerges indirect, mediate, unnatural, irregular inference.
In the two last Figures (Second and Third), the two terms hold the same
relation to the middle term in the premises ; ergo, no indirect inference, but
always two direct conclusions possible.
In the first Figure, as the two terms are subordinated to each other in the
premises, one direct conclusion from premises, whether read in Extension or
Comprehension, and, conseciuently, an indirect one also, — the First Figure
being first fisrure in Extensive quantity ; the Fourth Figure being first figure in
Comprehensive quantity. Direct and indirect moods in each.
1. Blunder about definition of major and minor terms by logicians (for
which Aristotle not responsible),' cause of fancy of a Fourth Figure, consti-
tuted by indirect moods in comprehension.
I See Stahl [NoUz tt Animadversionei in
Compendium DiaUcticum D. Conradi Horneii,
nunc primum ex Auetoris AMograpko editct cura
Caapari Poaneri Prof. Pub. Jena. 1666, Ad. h-
iii. c. riii.].
APPENDIX. 659
2. That predicate could have no prefinition, and, therefore, though thej
allowed its converse, the direct inference was not suffered. This in Fapesmo,
Frisesmo (these alone, by some logicians, admitted in the First Figure), and
Fesapo and Fresison in Fourth, or Comprehensive First.^
3. That major proposition, that which is placed first.
Fourth Figure. — The First Figure, and that alone, is capable of being
enounced in two orders, those of Breadth and of Depth. It is exactly the
same syllogism in either order ; and, while the order of Depth was usually
employed by the Greeks, Orientals, and older Latins, that of Breadth has been
the common, if not the exclusive, mode of enouncement among the western
logicians, since the time of Boethius. In either form thece are thus four direct
moods, and five indirect — in all nine moods ; and if the Figure be held to
comprise the moods of either form, it will have eighteen moods, as in fact is
allowed by some logicians, and, among others, by INIendoza (Disp. Log. et Met.
T. I. pp. 515, 516). Martianus Capella {De Septem Ariihus Liberalibuft, L. iv.,
De Dialectica^ in cap. Quid sit Prcedicaticus Sijllocjismus — see p. 639) states and
allows either form, but, like his contemporaries, Greek and Latin, he employs
in his examples the order of Depth.
Now, mark the caprice of the logicians of the West subsequent to Boethius.
Overlooking entirely the four direct moods in the order of Depth, which they
did not employ, as the conclusion would, in these cases, have been opposed to
their own order; they seized upon the five indirect moods of the order of
Depth, as this afforded a conclusion corresponding to their own, and consti-
tuted it, thus limited, into a Fourth Figure.
Did not make two forms of First Figure.
An indirect conclusion is in subject and predicate the reverse of a direct;
opposed, therefore, to the order of predication marked out by the premises
which the direct conclusion exclusively follows. An indirect conclusion (what
the logicians have not observed) ^ is an inference from the direct conclusion,
and, therefore, one mediate from the premises.
(5) MOODS OF FOURTH FIGURE REDRESSED.
(Early paper — previous to 1 844. Later signs of quantity substituted. — Ed.)
I. Bamalip, — only Barbara with transposed premises and converted con-
clusioa.
(2) All irons are (some) metals ;
(1) All metals are {some) minerals;
All irons are (some) minerals.
1 [That fourth Figure difTers from first only Dialect., Lib. ii. c. vi. art. xi. p. 391, and art.
by transposition of Premises, — held by De- iv. p. 385 (1635). Kidiger, De Sensu Veri et
rodon, Logica Restltuta, p. 606. Camerarius, Falsi, ii. 6, } 36. Crusius, Weg Zvr Gewisskeit,
DLtputationes Philosophical, Disp. i. qu. 13, p. § 336, p. 606. Tlatner, Philosophische Aphoris-
116. Caramuel, Rat. ft Jiedl. Phil.. Disp. xii. men, i. { 554, p. 267 ]
p. 45. Irenaeus, Integ. Phil., Elementa Logir.es, 2 But see Contarenus, De Quarta Figtira
Sect. ill. § 3, p. 29. Campanella, PAti. iiat. SyUog., Opera, Tp. 1235. — E.D.
660
APPENDIX.
(By conversion.)
Some minerals are {all) irons.
(Minerals) ,
a -.{Metals),
(Redressed)
: (Irons).
II. Calcmes, — only Celarent with transposed premise* and converted con-
cluaon.
(2) All snails are (some) mdUusca ;
(1) No molhiscum is any insect;
No snail is any insect.
(By conversion.)
No insect is any snail.
{Insect) :
IIL Dimatis, — only Darii with transposed premises and converted conclu-
sion.
(2) Some stars are {some or all) planets;
(1) All planets are some things moving round sun ;
Some stars are some things moving round sun ;
(By conversion.)
Some things moving round sun are some stars.
( Moving round Sun),
; (Planets) : , -
(Redressed)
I , (Stan)
APPENDIX.
66X
IV. Fesapo [Felapos].*
(2) No artery is any vein ;
(1) AU veins are (some) bloodvessels ;
No artery is (some) bloodvesseL
(By conversion.)
Some bloodvessel is no artery.
(^Bloodvessels) ,
s«:(Fem):-
(Redregsed)
'.{Artery)
V. Freslson [Frelilosj.
(2) No muscle is any nerve;
(1 ) Some nerves are (some) expansion on hand j
No muscle is (some) expansion on hand.
(By conversion.)
Some expansion on hand is no muscle.
{Expansion on hand),
, {Nerve) : —
(Redressed)
: {Muscle)
+
(March 1846.) — My universal law of Figured Syllogism excludes the
Fourth Figure. — What worse relation of subject and predicate subsists between
either of two terms and a common third term with which one, at least, is positively
related ; that relation subsists between the two terms themselves. What relation,
etc. ; that relation, etc. Now, in Fourth Figure this is violated ; for the predi-
cate and subject notions, relative to the middle term in the premises, are in the
conclusion turned severally into their opposites by relation to each other. This
cannot, however, in fact be ; and, in reality, there is a silently suppressed con-
clusion, from which there is only given the converse, but the conversion itself
ignored.
1 Zabarella, Optra Logira De Quarta Fig.
SyU. pp. 118, 119, 125. Burgersdyk, Instit.
Log., L. ii. c. 7, p. 167, reverses premises and
reduces to Fapesmo an indirect mood of
First; thus violating the rule of tliftt Fig-
ure.
6^2 APPENDIX-
Fourth Figure. Reasons against.
1", Could never directly, naturally, reach (a) Conclusion from premise,
or (b) Premises from qusesitum.
2°, All other figures conversion of premises of First, but, by conversion of
conclusion (as it is), no new figure.
3°, All other figures have one conclusion Fourth a converted one, often
different.
(March 1850.) — Fourth Figure. The logicians who attempt to show the
perversion in this figure, by speaking of higher and lower notions, are extra-
logical. Logic knows nothing of higher and lower out of its own terms; and
any notion may be subject or predicate of any other by the restriction of its
extension. Logic must show the perversion in this Figure ex facie syUofjismi,
or it must stand good. On true reason, why no Fourth Figure, see Aristotle,
Anal. Pr., L. i. c. 2S, § 8, and Pacius, in Commentate/.
(March 1850.) — Fesapo and Fresiso (also Fapesmo, Frisesmo) proceed on
the immediate inference, unnoticed by logicians, that the quantities, apart from
the terms, may, in propositions In A and Anl, be converted.
Averroes on Prior Analytics^ B. i. Ch. 8.
" If we ask whether A be in C, and say that A is in C, because A is in B,
and B in C ; in this case, there is a natural syllogism by general confession ;
and this in the First Figure.
" In like manner, if we say that A is not in C, becan.«c B is in C, and B is
not in A ; it is plain that we collect that conclusion by natural process ; and
this is the Second Figure, which is frequently found employed by men in their
ordinary discourse.
" In like manner, also, if we say that A is in C, because A and C are in B ;
that syllogism is also natural to us, and is the Third Figure. But if we say A
is in C, because C is in B, and B in A ; the reasoning is one which no one
would naturally make, for the reason that the quaesitum (that is, C to be in
A) does not hence follow — the process being that in which we say A is in C,
since A is in B, and B in C ; and this is something which thought would not
perform, unless in opposition to nature. From this it is manifest that the
Fourth Figure, of which Galen makes mention, is not a syllogism on which
thought would naturally light " (etc.). Thereafter follows a digression against
this figure. See also the same book, Ch. 23d, and the Epitome^ by Averroes,
of the same, Ch. i.
(c) FOURTH FiadRE,- AUTHORITIES FOR AITD AOAllTST.
Admitted by —
Ildefonsus do Penafiel, Cursus Philosophicus, Disp. Summul. D. iii. p. 39.
G. Camerarius, Dispul. Philos., P. i. q. xiii. p. 116. Port Royal Logic, p. iii.
c 8, and c. 4. Ridiger, De Sensu Veri et FaLtif L. ii. c. 6, § 36. Hauschius ii»
Acta Erud. ^. 470 et serj. Lips. 1728. Noldius, Logica Recognita, c. xii. ]y.
377. Crakanthorpe, Zo(7<Va, L. iii. c. XV. p. 194 (omitted, but defended). Lam-
hert, Neues Organon,!. §237 et seq. Hoffh&UQr, Analytik der Urtheile und
APPENDIX.
663
ScMusse, § 138. Twesten, Logilc, inshesondere die Anahjtik, § 110. Leibnitz,
Opera, ii. 357 ; v. 405 ; vi. 216, 217, ed. Dutens. Oddus de Oddis (v. Con-
tarenus. Nun Dari Quart. Fig. SijlL, Opera Omnia, p. 233, ed. Venet, 1589).
Rejected by —
Averroes, In An. Pnor, L. i. c. 8. Zabarella, Opera Logica, De Qitarta
Fig. SglL, p. 102 et seq. Purchot, Instit. Phil T. I. Log. P. iii. c. iii. p. 169.
Molinaeus, Elementa Logica, L. i. o. viii. Facciolati, Rudimenla Logica, P. iii.
c. iii. p. 85. Scaynus, Paraphrasis in Organ., p. 574. Timpler, Logicce Sys-
tema, L. iv. c. i. qu. 13, p. 543. Platner, Philosophisclie Aphorismen, I. p. 267.
Burgersdicius, Inatif. Log. L. ii. c. vii. p. 165. Derodon, Logica Resiituta, p.
606. Wolf, Phil. Rat., § 343 et seq. (Ignored.) HoUmann, Logica, § 453, p.
569. Goclenius, Prohlemata Logica, P. iv. p. 119. Keckermann, Opera, T. L
Syst. Log. Lib. iii. c. 4, p. 745. Arriaga, Cursus Philosophicus, In Summulas,
D. iii. § 5, p. 24. Aristotle, An. Prior, i. c. 23, § 8 ; c. 30, § 1 (omitted). Jo.
Picus Mirandulanus, Conclusiones, Opera, p. 88. Melanchthon, in 1st edition
of Dialectic, L. iii., De Figuratione (1520), afterwards (1547) restored (Heu-
.manni, Acta, iii. 753). Cardinalis Caspar Contarenus, Epistola ad Oddum de
Oddis, De Quart. Fig. Syll., Opera, p. 233 (1st ed., 1571). Trendelenburg,
Elementa Logica, § 28, etc. Herbart, Lehrbuch der Logik, Einleit. 3, § 71.
Hegel, Encyclopcedie, §187. Fries, System der Logik, % 57 h. Griepenkerl,
Lehrbuch der Logik, § 29 et seq. Drobisch, Logik, § 77, p. 70. Wallis, Institti-
tio Logicce, L. iii. c. ix. p. 1 79. ,
II. INDIRECT MOODS OF SECOND AND THIRD FIGURES.l
ii.
in.
(II. Fig.)
''Cesare
' Camestres
Festino
iv. j Baroco
j (in. Fig.)
i. { Darapti
ii. I Felapton
iii. /Disamis
iv. P-Datisi
Bocardo
vi. Ferison
Reflexim ; (1, 2, 5, 8, 9.)2 Cesares.
Beflexim; (2,5,8,9.) Camestre, Camestres, Faresmo
(only subaltern of Camestres) ; rejected (2), admitted
(3, 6.)
Premises reversed; (2, 3, 4, 5, 6, 7, 8, 9.) Firesmo,
Frigeros.
Premises reversed; (2,5,7,8,9.) Bocardo, Moracos,
Forameno.
Beflexim; (1, 2, 3, 4, 10, 11.)
Premises transposed; (4, 5, 6,7, 8, 9, 11.) Fapemo,
Fapelmos.
JJe^xim;(4, 7, 10, 11.) :
i?e^«rwH.-(4, 7, 10, 11.) ;■
Premises transposed; (4, 7, 9, 11.) Baroco, Macopos,
Danorcoc.
Premises transposed; (4, 5, 6, 7, 8, 9, 11.) Frisemo,
Fiseros.
1 The indirect Moods of the First Figure 2 The numbers within brackets refer to the
are universally admitted. authorities given on following page. — Ed.
664
APPENDIX.
(II. Fis.)
1.
Mart. Capella
Cesare, reflexim.
2.
Duns Scotus
Cesare and Camestres, conclusions simply converted ;
Festino and Baroco. Rejects (and rightly) what
has since been called Faresnio, as a mere subaltern
of Camestres {An. Pr. L. i. qu. 23. See also Conim-
bricenses, In Arist. Dial. II. p. 362).
3.
Lovanienses, (153."))
Faresmo, Firesmo.
4.
Paciiis, (1584)
Firesmo (on An. Pr. L. i. c. 7, and relative place of his
Com. AnaJ.).
5.
Gonirabricenses
Record that indirect moods from Cesare and Cames-
tres; and also Friseso, Bocardo were admitted by
some " recentiores" (II. p. 362).
6.
Burgersdicius, (1626)
Faresmo, Firesmo.
7.
Caramuel, (1642)
Moracos, Frigesos.
8.
Scheibler, (1^53)
Cosurcs, Camestres, Firesmo, Bocardo.
9.
Noldius, (1666)
Cesares, Camestre, Firesmo, Foramcno (he has for
the direct mood Facrono, in place of Baroco).
(HI. Fig.)
1.
Apnleius
Darapti, reflexim.
2.
Cassiodorus
Do.
3.
Isodoms
Do.
4.
Duns Scotos
Darapti, Disamis, and Datisi, their conclusions simply
converted; Felapton, Bocardo, Ferison (Sup. An.
Pr. L. i. qu. 24).
5.
Lovanienses
Fapemo, Frisemo (ib.).
6.
Pacius
Fapemo, Frisemo (ib.).
7.
Conimbricenses
Record that some " recentiores" admit indirect moods
from Darapti, Disamis, Datisi; also Fapesmo, Fri-
sesmo, and Baroco.
8.
Burgersdicius
Fapemo, Frisemo.
9.
Caramuel
Fapelnios, Macopos, Fiseros.
10.
Scheibler
Admits them from Disamis, Datisi, Darapti, but not
from those which conclude particular negations.
11.
Noldius
Danorcoc (ho has for Bocardo Docamroc), Frisemo,
Fapemo, and what are converted ftom Darapti,
Disamis, and Datisi without names.
Darapti virtually two moods; this maintained by Theo-
phrastns.
Indirect moods are impossible in the Second and Third Figures, for what are
called indirect conclusions are only the direct conclusions. Mem., that in the
Second Cesare and Camestres are virtually one ; while in the Third Figure
Darapti is virtually two, as Disamis and Datisi are one.
APPENDIX
665
For the particular quantification of the Predicate, useful illustrations, as in
the First from Fapesmo, Frisesmo, or (in the pseudo Fourth) from Fesapo
and Fresiso ; so in the Second Figure of what have been called the indirect
moods of Figure II.
Figure U.
1. Bocardo.
2. Firesmo.
1. Baroco.
2. Fapemo.
3. Frisemo.
(1853.) Blunders of Logicians. — What have been called the Indirect Moods
of the Second and Third Figures, arise only from the erroneously supposed
transposition of the premises ; and the Fourth Figure is made up of the really
indirect moods of the First Figure, with the premises transposed.
III. — NEW MOODS — NOTES UPON TABLE OF SYLLOGISMS.^
Fig. I. vi. — Corvinus {Institutiones PkilosopJdcE Rationalls, 1 742, § 540)
says : — " There sometimes appears to be an inference from pure particulars.
For example, Some learned are [some'] ambitious men ; some men are [all the]
learned; therefore, some men are ambitious. But the minor proposition,
although formally particular, involves, however, a universal, to wit, its con-
verse, — All the learned are [some] men, — which Is equipollent." Why not,
then, scientifically enounce (as I have done), without conversion, what the
thought of the convertend already really and vulgarly involved ?
In all Figures. — I have not been undoubtful whether the syllogisms of the
class in which the two premises, being tlie same, arc mutually interchangeable,
should be regarded as a single or as a double mood. Abstractly considered
from all matter, the mood Is single; for the two premises, however arranged.
1 See Appendix XI. — ED.
84
666 APPENDIX.
afibrd only a repetition of the same form. But so soon as the form is applied to
any matter, be it even of a symbolical abstraction, the distinction of a double
mood emerges, in the possible interchange of the now two distinguished
premises. To the logicians this question was only presented in the case of
Darapti (III. ii.) ; and on this they were divided. Aristotle {An. Pr. i. c. 6,
§ 6) contemplates only one mood ; but his successor, Theophrastus, admitted
two (Apuleius, De Hah. Doctr. Platonis, L. iii. Op. p. 38, Elm). Aristotle's
opinion was overtly preferred by Alexander (arf locum, f. 30, ed. Aid. quoted
above, p. 63C), and by Apuleius (/. c.) ; whilst that of Theophrastus was
adopted by Porphyrj-, in his lost commentary on the Prior Analytics, and,
though not without hesitation, by Boethius (Z)e Syll. Categ. L. ii., Op. pp. 694,
598, 601, 604). The other Greek and Roman logicians silently follow the
master ; from whom, in more modern times, Valla (to say notliing of others)
only differs, to reduce, on the counter-extreme, Ccsare and Camestres (II. ix.
a, and x. b), and, he might have added, Disamis and Datisi (III. iv. v.), to a
single mood (De Dial., L. ii. c. 51). (For the observations of the Apbrodisian,
see above, p. 633 et seq.)
To me it appears, on reflection, right to allow in Darapti only a single
mood ; because a second, simply arising through a first, and through a transpo-
sition, has, therefore, merely a secondary, correlative, and dependent existence.
In this respect all is different with Cesare and Camestres, Disamis, and Datisi.
The principle here applies in my doctrine to the whole class of syllogisms with
balanced middle and extremes.
Fig. II. xii. b. — David Derodon (Log. Rest De Arg., c. ii. § 61), in canvass-
ing the special rule of the Second Figure, — that the major premise should be
universal, — he now approbates, he now reprobates syllogisms of this mood ;
but wrong on both alternatives, for his admissions and rejections are equally
erroneous. " Hie syllogismus non valet : — Aliquod animal est [^aliquod] ration-
ale ; sed [ti//us] acinus non est [ullus'l rationalis ; ergo [^ullus] asintis non est
[_aliquod^ animal." (P. 635.) The syllogism is valid; only it involves a prin-
ciple which Derodon, with the logicians, would not allow, — that in negatives
the predicate could be particular. — (See Log. Rest. De Argument, c. ii. § 28, p.
628.) Yet almost immediately thereafter, in assailing the rule, he says : — "At
multi dantur syllogismi constantes majori particulari, qui tamen sunt recti;
ut, — Aliquod animal non est [Janus'] lapis; sed [^omni.s'] adamas e.it [^aliquis]
lapis; ergo, [u//u.>}] adamas non est [aliquod'] animal." (This syllogism is,
indeed, II. iii. a ; but he goes on :) '' Item : Aliquod animal est [aliquod]
rationale; sed [idlus] lapis non est [ullus] rationalis ; ergo [u/Zits] laj>is non est
[aliquoiQ animal." Now, tliese two syllogisms are both bad, as inferring what
Derodon thinks they do infer, — a negative conclusion, with, of course, a
distributed predicate (p. 623) ; are both goo<l, as inferring what I suppose
them to infer, — a negative conclusion with an undistributed predicate.
Fig. III. viii. b. — Derodon (//>«</. § 54), in considering the Special Rule
of the Third Figure, — that the minor premise should be affirmative, — alleges
the following syllogism as *^ cirious :" — ^'Omni.i homo est [aliquod] animal; sed
[ullus] homo non est [ullus] asinus ;' ergo, [ullus] a.s-mus non est [aliquod]
APPENDIX. 667
animal" (p. 638). It is a virtuous syllogism, — with a particular predicate
(and not a universal, as one logician imagines) in a negative conclusion.
Again (omitting his reasoning, which is inept), he proceeds: — "Hie vero
syllogismus uon est vitiosus, sed rectus: — l_Omnis'] homo est Iquidaml rationalis,
sed \_uUusJ homo non est \ullus'\ asinus [or Dens'] ; erfjo, [u//us] asinus [or Deus]
nan est \_quidam2 rational^." This syllogism is indeed correct ; but not as
Derodon would have it, with a distributed predicate in the conclusion. That
his conclusion is only true of the asinus, per accidens, is shown by the substitu-
tion of the term Deus ; this showing his illation to be fonnally absurd.
Fig. III. ii. — Derodon (Ibid.) says: — "Denique, conclusionem in tertia
figura debere esse particularem, non universalem, statuunt communiter Philos-
ophi; unde hie syllogismus non valet; — ^Omnis homo est [^quidam] rationalis;
sed omnis homo est [^quoddam] animal ; ergo, omne \_quoddam~\ animal est \_quod~
dam] rationale.' Verum, licet conclusio sit universalis, syllogismus erit bonus,
modo," etc. (p. 638). The syllogism is, and must remain, vicious, if the subject
and predicate of the conclusion be taken universally, whilst both are undis-
tributed in the antecedent. But if taken, as they ought to be, in the conclusion
particularly, the syllogism is good. Derodon, in his remarks, partly overlooks,
partly mistakes, the vice.
Derodon, criticizing the Special Rule of the First Figure, — that the major
premise should be universal, — says, inter alia : — "At multi dantur syllogismi
primae figuraj constantes major! particulari, qui tamen sunt recti: ut, — '■Aliquod
animal est [aliquod] rationale ; sed honm est [aliquod] animal ; ergo, [! !] homo
est [aliquis] rationalis': item," etc., etc. (p. 627). This syllogism is vicious ;
the middle term, animal, being particular in both its quantifications, affords no
inference.'
XL
LOGICAL NOTATION.
(Seep. 215.)
I. — Lambert's Linear Notation.^
This very defective, — indeed, almost as bad as possible. It has accordingly
remained unemployed by subsequent logicians ; and although I think linear
diagrams do afford the best geometrical illustration of logical forms, I have
found it necessary to adopt a method opposite to Lambert's, in all that is
peculiar to him. I have been unable to adopt, unable to improve, anything.
1°. Indefinite or particular notions can only be represented by the relation
1 Seep. 559. —Ed. the schemes of Lambert and Euler, see S.
2 For Lambert's scheme of notation, see his Maimon, Vtrsuch einer neuni Logik, Sect, iv.,
jVeuts Organon, L § 21 ; and for a criticism of § 7, p. 64 et xeq. Berlin, 1794. — Ed.
068 APPENDIX.
of two lines, and in two ways : 1°, One being greater than the other; 2*, One
being partially out of relation to the other. Instead of this, Lambert professes
to paint particularity by a dotted line, t. e., a line different by an accidental
quality, not by an essential relation. But not even to this can he adhere, for
the same notion, the same line, in different relations, is at once universal and
particular. Accordingly, in Lambert's notation, the relation of particular
notions is represented sometimes by a continuous, sometimes by a dotted line,
or not represented at all. (See below, 1*, 1, 2, 3, 4, 5.)
2°, The inconsistency is seen at all climax in the case of the predicate io
affirmatives, where that term is particular. In Lambert's notation it, however,
shows in general as distributed or univei'sal ; but in this he has no constancy.
(See 1*, 1, 2, 3, 4.) But the case is even more absurd in negative propositions,
where the predicate is really taken in its whole extent, and yet is, by the dot-
ted line, determinately marked as particular. (See 4.)
3°, The relation of negativity, or exclusion, is professedly represented by
Lambert in one line beyond, or at the side of, another. This requires
room, and is clumsy, but is not positively erroneous : — it does express exclu-
sion. But his affirmative propositions are denoted by two unconnected Hnes,
one below the other. This is positively wrong ; for here the notions are equally
out of the other, as in the lateral collocation. But even in this he is inconsist-
ent ; for he as often expresses the relation of negativity by lines in the relation
of higher and lower. (See below, 1, 4.)
4°, He attempts to indicate the essential relation of the lines by the fortuitous
annexation of letters, the mystery of which I have never fathomed.
5°, He has no order in the relation of his lines.
The middle term is not always the middle line, and there is no order between
the extremes.
This could not indeed be from his method of notation ; and except it be ex-
plained by the affixed letters, no one could discover in his lines the three com-
paicil notions in a syllogism, or guess at the conclusion inferred. (See 1 — 5.)
6°, P'rom poverty the same diagram is employed to denote the most different
moods in affirmative and negative. (Compare 2 and 3 with 4.)
7°, No order in the terms in the same figure.
8°, Incomplete. Lambert can represent ultra-total, etc., included in affirma-
tive, but not ultra-total excluded in negative. Has the merit of noticing this
relation.
9°, Lambert — but it is needless to proceed. What has been already said,
fihows that Lambert's scheme of linear notation is, in its parts, a failure, being
only a corruption of the good, and a blundering and incongruous jumble of
the natural and conventional. The only marvel is, how so able a mathemati-
cian should have pro[)Ounded two such worthless mathematical methods. But
Lambert's geometrical is worse even than algebraic notation.
To vindicate what I have said, it will be enough to quote his notation of the
moods of the Third Figure (I. p. 133), which I shall number for the previous
references.
APPENDIX. 669
III. Figure.
I.* Darapti. . . . . C c . . . .
M m
. . . . B b . . . .
1. Felapton. M mC c
B b
2. Disamis. B b
M m
. . . C
3. Datisi. C c
M m
. . B
4. Bocardo. B b
M m
C
5. Ferison. M m C c
. . B
11. — NOTATIOX BY MaA88.
Professor Maass, of Halle,' discontented, not unreasonably, with the geomet-
rical notations of Lambert and Euler, has himself proposed another, compared
with which those of his predecessors show as absolutely perfect. It will be
sufficient to despatch this scheme with a very few remarks. To use it is wholly
impossible ; and even the ingenious author himself has stated it towards the
conclusion of his Logic (§§ 495 — 512), in the course of which it is not (if I recol-
lect aright) honored with a single reference. It is, however, curious, as the only
attempt made to illustrate Logic, not by the relations of geometrical quantities,
but by the relations of geometrical relations — angles.
1°, It is fundamentally wrong in principle. For example, Maass proposes
to represent coinclusive notions — notions, therefore, to be thought as the same
— by the angles of a triangle, which cannot possibly be imaged as united ; for
surely the identity of the concepts, triangle, trilateral, and figure icith angles
equal to two right angles, is not illumined by awarding each to a separate corner
of the figure. On the contrary, coexclusive notions he represents by angles in
similar triangles, and these can easily be conceived as superposed. The same
may be said of coordinates. But, waiving the objection that the different angles
of a figure, as necessarily thought out of each other, are incapable of typifying,
by their coincidence, notions to be thought as coinclusive, — it is further evident
that the angles of an equilateral triangle cannot naturally denote reciprocal or
1 Grundriss der Logik, 1793. I quote from do of Maass' scheme of notation; for his
the fourth edition, 1S23. 1 regret the neces- Logic is one of the best compends published
8ity imposed on me of speaking in the way I even in Germany.
670 APPENDIX.
wholly identical notions, in contrast to others partially identical ; for every angle
of every triangle Infers, — necessitates, — contains, if you will, — the whole of
everj' other, equally as do the several angles of an equilateral triangle.
2°, But Maass is not consistent. He gives, for Instance, a triangle (Fig. 12)
to illustrate the subordination of one notion to another ; and yet he represents
the lower or contained notion by an obtuser, the higher or containing notion
by an acuter, angle.
3°, The scheme Is unmanifest, — In fact, nothing can be less obtrusive. Il
illustrates the obscure by the obscure, or, rather, it obscures the clear. Requir-
ing itself a painful study to comprehend Its Import (if comprehended it be),
instead of informing the understanding through the eye. It at best only addresses
the eye through the understanding. Difficult ; — we only regret that it had
not been Impossible.
4°, It is clumsy, operose, complex, and superfluous. For, to represent a
notion denoted by a single angle, it is compelled to give the redundance of a
whole triangle ; and three repugnant notions demand an apparatus of three
several figures, and six vacant angles. In fact, the only manifestation to which
this scheme of angles can pretend, is borrowed from the scheme of figures
which it proposes to supersede.
5°, It Is wholly dependent upon the accidents of foreign aid. To let it work
at all, it calls in to its assistance an indefinite plurality of figures, a Greek and
Latin alphabet, combinations of letters straight and deflected, and an assort,
ment of lines, thick and thin, plain and dotted. I have counted one diagram
of the eighteen, and find that It Is brought to bear through three varieties of
line, four triangles, and eleven letters.
It is needless to enumerate its other faults, Its deficiencies, excesses, ambigu-
ities, etc. ; transeat in pace.
in. — The Author's Notatioh.
NO. 1. LINEAR.
The notation .previously spoken of represents every various syllogism in all
the accidents of Its external form. But as the number of Moods in Syllogisms
Analytic and Synthetic, Intensive and Extensive, Unfigured and Figured (and
of this in all the figures), are the same ; and as a reasoning, essentially identi-
cal, may be carried through the same numerical mood, in every genus and
species of syllogism. It seems, as we should wish it, that there must be possible,
also, a notation precisely manifesting the modal process, in all its essential dif-
ferences, but, at the same time, In its Internal identity, abstract from every acci-
dental variety of external form. The anticipation and wish arc realized, and
realized with the utmost clearness and simplicity, in a notation which fulfils, and
alone fulfils, these conditions. This notation I have long employed ; and the two
following are specimens. Herein, four common lines are all the requisites : three
(horizontal) to denote the terms ; one (two ? — perpendicular), or the want of it,
at the commencement of comparison, to express the rjualiti/ of aflirniatlon or
of negation ; whilst (juanlihj is marked by the relative length of a terminal
1 See Tabular Scheme at the end of the present volume. — £d.
APPENDIX. 671
line within, and its indefinite excurrence before, the limit of comparison. This
notation can represent equally total and ultra-total distribution, in simple Syllo-
gism and in Sorites ; it shows at a glance the competence or incompetence of any
conclusion ; and every one can easily evolve it.
Of these, the former, with its converse, includes Darii, Dabitis, Datisi, Disa-
mis, Di maris, etc. ; whilst the latter, with its converse, includes Celarent, Cesare,
Celanes, Camestres, Cameles, etc. But of these, those which are represented
by the same diagram are, though in different figures, formally the same mood.
For in this scheme, moods of the thirty-six each has its peculiar diagram ;
whereas, in all the other geometrical schemes hitherto proposed (whether by
lines, angles, triangles, squares, parallelograms, or circles), the same (complex)
diagram is necessarily employed to represent an indefinite plurality of moods.
These schemes thus tend rather to complicate than to explicate, — rather to
darken than to clear up. The principle of this notation may be realized in
various forms.'
The problem, in general, is to manifest, by the differences and relations of
geometrical quantities (lines or figures), the differences and relations of logical
forms. The comparative excellence of any scheme in solution of this problem
will be in proportion as it is, 1°, Easy ; 2°, Simple ; 3°, Compendious ; 4°, All-
sufficient; 50, Consistent; 6°, Manifest; 7°, Precise; 8°, Complete.
In the scheme proposed by me,
1°, I denote terms or notions by straight lines ; and, as a syllogism is consti-
tuted by three related notions, it will, of course, be represented by three re-
lated lines.
2°, I indicate the correlation of notions by the order and parallel coexten-
sion of lines. (The perpendicular order and horizontal extension, here
adopted, is arbitrary.)
3°, Lines, like notions, are only immediately related to those with which
they stand in proximity. Hence the intermediate line in our diagram, repre-
senting the middle term of a syllogism, is in direct relation with the lines
representing the extremes, whereas the latter are only in mutual correlation
through it.
4°, The relative quantity of notions is expressed by the comparative length
of the related lines. In so far as a line commences (here on the left) before
another, it is out of relation with it, — is indefinite and unknown. Where a
line terminates under relation (here towards the right), it ceases absolutely to
be. A line beginning and ending in relation indicates a whole notion. A
line beoinninT before or ending after its correlative indicates a part of a
1 neprinted from Discussions, p. 657. For a further explanation of the relations denoted
by the diagrams, Bee p. 134. — Ed.
672 APPENDIX.
5", The kinds of correlation, Affirmation and Negation, arc shown by tlio
connection or non-connection of the lines (here from the left). The connec-
tion (here a perpendicular line) indicates the identity or coindusion of the
connected terms ; the absence of this denotes the opposite. The lines in posi-
tive or affirmative relation are supposed capable of being slid into each other.
This geometric scheme seems to recommend itself by all the virtues of such
a representation, and thus stands favorably contrasted with any other. For it
is Ccisy, — simple, — compendious, — all-suffiicient, — consistent, — manifest, —
precise, — complete.
1°, Easy. — Linear diagrams are more easily and rapidly drawn than those
of figure ; and the lines in this scheme require, in fact, no symbols at all to
mark the terminal differences, far less the double letterings found necessary by
Lambert.
2°, Simple. — Lines denote the quantity and correlation of notions far more
simply than do any geometric figures. In those there is nothing redundant ;
all is significant.
3°, Compendious. — In this respect lines, as is evident, are far preferable to
figures ; but Lambert's linear scheme requires more than double the space suf-
ficient for that here proposed.
4°, All-sufficient. — Any scheme by figures, and Lambert's scheme by lines,
is, in itself, unintelligible, and depends on the annexation of accidental sym-
bols to enable it to mark out the differences and relations of terms. Lambert,
likewise, endeavors to supply this exigency by another means, — by the fortui-
tous quality (his dottings) of certain lines. In our scheme lines, simple lines,
and lines alone, are sufficient.
6°, Consistent. — Lambert's linear scheme is a mere jumble of inconsisten-
cies. Compared with his, those by figures are, in this respect, far preferable.
But the present linear scheme is at once thorough-going, unambiguous, and
consistent.
6°, Manifest. — In this essential condition^ all other geometrical illustrations
are lamentably defective. In those by figure, each threefold diagram, typifying
an indefinite plurality of moods, requires a painful consideration to extract out
of it any pertinent elucidation ; this is, in fact, only brought to bear by the
foreign aid of contingent symbols. Nor can these schemes properly represent
to the eye the relation of the toto-total identity of a plurality of terms ; the
intention requires to be intimated by the external accident of signs. Lambert's
lines sink, in general, even below the figures, in this respect. But as lines
are here applied, the sole pertinent Inference leaps at once to sense and undei^
standing.
7°, Precise. — Ambiguity, vagueness, vacillation, redundancy, and, withal,
inadequacy, prevail in the other schemes. In those by figure, one diagram is
illustrative of as many as a dozen moods, positive and negative ; and a single
mood may fall to be represented by four diagrams, and perhaps in six several
ways. Lambert's lines are even worse. In our scheme, on the contrary, every
mood has a diagram applicable to itself, and to itself exclusively, whilst every
possible variety of its import has a corresponding possible variety of linear
difference.
8*^, Complete. — In this last and all-important condition, every scheme
APPENDIX. 673
hitherto proposed is found to fail. A thorough-going, adequate, and pliant
geometric method ought equally and at once to represent the logical moods in
the Un figured and Figured Syllogism, in the Syllogism Synthetic and Analytic,
in Extension and Intension, — this, too, in all their mutual convertibilities, and
in all their individual varieties. This our scheme performs, but exclusively. So
much in general. Again, in particular : — Of the figures, circles and triangles
are necessarily inept to represent the ultra-total inclusion or coexclusion of
terms, — in a word, all the relations of proportion, except totality and indefinite
partiality ; whilst quadrilateral figures are, if not wholly incompetent to this,
operose and clumsy. Lambert's linear method is incompetent to it in nega-
tives ; and such inability ought to have opened his eyes upon the defects of the
whole plan, for this was a scheme which he expressly proposed to accomplisL
The present scheme, on the other hand, simply and easily affirms this, ip
affirmation and negation, and with any minuteness of detail.
AUTHORS SCHEME OF NOTATION UNFIGURED AND FIGURED SYLLOGISM
NO. II.
(1853.) The following Diagram (see p. 674) affords a condensed view
of my other scheme of Syllogistic Notation, fragments of which, in detail, will
be found in Mr. Thomson's Outline of the Laws of Thought, and in Mr. Baynes*"
Essay on the Nciv Analytic of Logical Forms. The paragraphs appended will-
supply the necessary explanations.
1.) A Proposition (jStdarrifM, intervallum, irpSrcuns, literally protensio, the-
stretching out of a line from point to point) is a mutual relation of two •
terms {ppoi) or extremes (&KpoL). This is therefore well represented, — The-
two terms, by two letters, and their relation, by a line extended between^
them.
2.) A Syllogism is a complexus of Three Terms in Three Propositions. — It
is, therefore, adequately typified by a Triangle, — by a Figure of three lines -
or sides.
3.) As upwards and downwards is a procedure arbitrary in the diagram, the ■
diagram indicates that we can, indifferently, either proceed from the Premises -
(rationes) to the Conclusion (rationatum), or from the Conclusion to the Prem-
ises; the process being only, in different points of view, either Synthetic or-
Analytic. (An exclusive and one-sided view, be it remembered, has given an,
inadequate name to what are called Premises and Conclusion.)
4.) Rationally and historically, there is no ground for constituting that
Premise into Major which is enounced frst, or that Premise into Minor which
is enounced last. (See after, p. 697, etc.) The moods of what is called the
Fourth Figure, and the Indirect moods of the First Figure, are thus identified.
In the diagram, accordingly, it is shown, that as right or left in the order of
position is only accidental, so is first or last in the order of expression.
85
eu
APFEHriXlX.
^
fro'
©
u
ex.
Co
Unflgured S.
% ^ ^
©
Bzvadtk
mm»
Order
Either or Neither.
5.) The diagram truly represents, by its various concentric triangles, the
Uh figured Syllogism, as involving the Figured, and, of tlie latter, the First
Figure as involving the two others. (In fa<?t, the whole differences of Figure
and Figures are accidental ; Moods alone are essential, and in any Figure and
in none, these are always the same and the same in number.)
6.) Depth and Breadth, Subject and' Predicate, are denoted by the thick
and thin ends of the same propositioual line.
7.) Depth and Breadth are quantities always coexistent, always correlative,
each being always in the inverse ratio of the other. This is well shown in the
connection and contrast of a line gradually diminishing or increasing in thick*
ness from end to end.
XPPENDFX. 676
8.y But though always coexistent, and consequently always, to some amount,
potentially inferring each other, stitt we cannot, without the intervention of an
actual inference, at once jump from the one quantity to the other, — change,
per saltum, Predicate into Subject, and Subject into Predicate. We must
proceed gradatim. We cannot arbitrarily commute the quantities, in passing
from the Qutesitum to the Premises, or in our transition from the Premises to
the Conclusion. When this is apparently done (as in the Indirect moods of
the First Figure and in all the moodc of the Fourth), the procedure is not only
unnatural, but virtually complex and mediate; the mediacy being concealed by
the concealment of the mental inference which really precedes. Indicated by tlie
line and broken line for the First Figure.
9.) In Syllogism, Figure and the varieties of Figure are determined by the
counter relations of Subject and Predicate subsisting between the syllogistic
terms, — between the Middle and Extremes. All adequately represented;
10.) Figure and the differences of Figures all depending upon the difference
of the mutual contrast of Subject and Predicate between the syllogistic terms ;
<onsequently, if this relation be abolished, — if these terms be made all Sub-
jects (or it may be all Predicates), the distinction of Figure will be abolished
also. (We do not abolish, be it noted, the Syllogism, but we recall it to one
simple form.) — And this Is represented In the diagram. For as the opposition
of Subject and Predicate, of Depth and Breadth, is shown in the opposition
of the thick and thin ends of the same tapering line ; so where (as in the out-
most triangle) the proposltlonal lines are of uniform breadth, it is hereby
shown that all such opposition Is sublated.
11.) It is manifest that, as we consider the Predicate or the Subject, the
Breadth or the Depth, as principal, will the one premise of the Syllogism or
the other be Major or Minor; the Major Premise in the one quantity being
Minor Premise In the other. Shown out in the diagram.
1 2.) But as the First Figure Is that alone in which there Is such a difference
of relation between the Syllogistic Terms, — between the Middle and Extreme,
so in it alone is such a distinction between the Syllogistic Propositions realized.
By the diagram this Is made apparent to the eye.
13.) In the Unfigured Syllogism, and in the Second and Third Figures,
there Is no difference between the Major and Minor Terms, and, consequently,
no distinction (more than one arbitrary and accidental) of Major and Minor
Propositions. All conspicuously typified.
14.) All Figured Syllogisms have a Double Conclusion, bat in the different
figares in- at different way. Tbi* is well represented.
15.) The Double Conclusions, both equally direct, in the Second and Third
Figures, are shown in the crossing of two counter and corresponding lines.
676 APPENDIX.
The logicians are at fault in allowing Indirect Conclusions in these two figures,
— nor is Aristotle an exception. (See Pr. An., I. vii. § 4.)
16.) The Direct and Indirect Conclusions in the .First Figure are distinctly
typified by a common and by a broken line ; the broken line is placed im-
mediately under the other, and may thus indicate that it represents only ia
reflex of, — a consequence through the other (jcar' kvdKXaaiv, rejlexiin, per
rejlexionem). The diagram, therefore, can show that the Indirect moods of
the First Figure, as well as all the moods of the Fourth, ought to be reduced
to merely mef/i'a^e inferences; that is, to conclusions from conclusions of the
conjugations or premises of the First Figure.*
[The following Table affords a view in detail of the Author's Scheme of
Syllogistic Notation, and of the valid Syllogistic Moods (in Figure), on his
doctrine of a quantified Predicate. In each Figure (tliree only being allowed)
there are 12 Aflirmative and 24 Negative moods; in all 36 moods. The
Table exhibits in detail the 12 Affirmative Moods of each Figure, and the 24
Negative Moods of the First Figure, with the appropriate notation.
The letters C, T, each the third letter in its respective alphabet, denote the
extremes; the letter M denotes the middle term of the syllogism. Definite
quantity (all, any) is indicated by the sign (:) ; indefinite quantity (some) by
the sign (, or ,). The horizontal tapering line (■■ ) indicates an affirm-
ative relation between the subject and predicate of the proposition. Negation
is marked by a perpendicular line crossing the horizontal (■ [ ). The
negative syllogisms, in all the Figures, are exactly double the number of the
affirmative; for every affirmative affords a double negative, as each of its
premises may be marked by a negative. In Extension, the broad end of the
line denotes the subject, the pointed end the predicate. In Comprehension
this is reversed; the pointed end indicating the subject, the broad end tho
predicate. By the present scheme of notation, we are thus able to read a
syllogism both in Extension and in Comprehension. The line beneath the
three terms denotes the relation of the extremes of the conclusion. Predesig-
nation of the conclusion is marked only when its terms obtain -a different
quantity from what they hold in the premises. Accordingly, when not marked,
the quantification of the premises is held repeated in the conclusion. In tho
Second and Third Figures, — a line is inserted above as well as below the
terms of the syllogism, to express the double conclusion in those figures. The
symbol ^-'--r-^ shows that when the premises are converted, the syllogism
remains in the same mood ; ^!>-<d shows that the two moods between whicli
it stands are convertible into each other by conversion of their premises. The
middle term is said to be Balanced, when it is taken definitely in both premises.
The extremes are balanced, when both are taken definitely ; unbalanced, when
the one is definite, and the other is not
1 Reprinted from DiactuHom, pp. 657—661. — Ed.
APPENDIX. 677
The Table here given exhibits the author's final arrangement of the Syllo-
gistic Moods. The Moods are either A), Balanced^ or B), Unbalanced. In the
former class both Terms and Propositions are Balanced, and it contains two
moods, — i. ; ii. In the latter class there are two subdivisions. For either, a),
the Terms are Unbalanced, — iii. iv. ; or, b), both the Terms and Propositions
are Unbalanced, — v. vi. ; vii. viii. ; ix. x. ; xi. xii.
It should be observed that the arrangement of the order of Moods given in
the present Table differs from that of the earlier scheme printed above, p. 537
et seq. The following is the correspondence in the order of moods :
Present and
Earlier
Final Table.
Table.
L
corresponds
to
I.
n.
u
u
n.
m.
u
It
XI.
IV.
u
ii
xn.
V.
<i
((
vn.
VI
((
u
vm.
VII.
«
(i
HI.
VIU.
u
it
IV.
IX.
«(
u
V.
X.
«
it
VL
XI.
«
((
IX.
xn.
u,
u
X.
The order of the earlier Table is that given by Mr. Baynes, in the scheme of
notation printed at p. 76 of his Essay on (he New Analytic. The order of the
present Table corresponds with that given by Dr. Thomson in his Laws of •
Thought, p. 244, 3d edition, 1853. — Ed.]
AiPPJ^lJipiX.
SCHEME Oi< i^OTATION-^
'.OABI.K OF SYLLO-
A. AFFIRMS Til^L MOODS
Fig. I. Fig. il
i. C: . ; M : :Y C r—^ : M : ..r
ii. C,,, — :M: ,r C^i...^ :M: ^,r
p '
iii. C. :M, - -:r C,^^ :M, :r
iv. C;~ , M : >r 0:^^ , M : .,r
V. c,-^ — :M, — ,r OS- — -M, — ,r
vi. C. . M : ,r ' \ , M : .,r
Vii. C: : M : ,£' C:- — : M : — -,F
viii. C» : M : ^l'' q»- : M ; ^:p
ix. C: : M. :r 0* •' M , :l
v-
X. C: , M : <T C: , M :
xi. C: : M, ^.r C; : M, ^,r
1^ xii. C. , M : :r C.— » M : —.-r
'yth. —A. i. and ii. mre Balanced B ibe other moods are UnboUaiiced. Of these,
APPENDIX.
679
FIGURED SYLLOGISM.
GiSTIO MOODS.
A. AFFIRMATIVE MOODS.
Fig. III.
G:-
C-
C:-
: M
-:r
M
:M,
,M:
C, — - :M,
-.T
c,-
C:-
» ■
C:-
»"
C:-
C:-
,M
: M:
: M:
:M,
,M:
M,
,r
>r
:r
T
■>
.r
■»
, M:
B. NEGATIVE MOODS.
Fig. I.
aC:-4— :M : -.T
11.
iii.
IV.
V.
VI.
vu.
VIU.
IX.
X.
XI.
Xll.
bC:
aC-
bC,
aC,+r
bC,^^^^
M
M
M
M
M
■:r
■,r
■,r
.:r
\bC:— -^M|_4— ,r
a C ,-4^ : M , — , r
b C , : M ,
a C ,4— , M
bC, — - ,M
J a C :±- : M
bC:
aC,
bC,
aC:
bC:
aOl
bC:
M
M
M
M,
M,
,M:
,M:
aC:-f
bC:-
:M,
M,
+
,r
,r
,r
, r
,r
:r
:r
:r
.:r
:r
,r
aC,+- >M: :r
b c , — , M : -h- : r
lil and ir. are unbalanced in terms only, not in propositions; th« r«st in both.
I N^ D E X.
Abstract of General Logic, see Logic.
Abstraction or Generalization, what, 88,
104-5 ; its synonyms, 16.
Academical Disputation, 493.
AcciDEKTB, or Kxtiinsic Denominations,
wliat, 153.
Acquisition of Knowledge, Doctrine of, see
Logic.
Affections or Passions, as a source of error,
see Error, causes of.
ArRAMUS, quoted on the nature of experi-
ence, 444.
AonicoLA, Rodolphus, 198.
Albertus Magnus, referred to on genus of
Logic, 7; quoted on province of Logic,
20; quoted on quantification of predicate,
553-4.
Aldrich, Dean, his Compendium, 21 ; his
abusive employment of the terms hypofluti-
cal and conditional, 167; his abuse of the
phrase propositio exposita, 185, 249.
Alexander of Aptirodisias, the oldest com-
mentator on Aristotle, 4; refierred to as to
his use of the term \oyiK7\, ib.; has the
distinction of Abstract or General and Ap-
plied or Special Logic, 38; bis illustration
of the distinction, 38-9, see Logic; 198, 199;
on principle of name of major and minor
terms, 207, 215, 240 ; referred to on quantity
of hypothetical syllogisms, 247, 278, 296, 336,
514; quoted on quantification of predicate,
649; his ground of the discrimination of
major and minor terms in the second and
third Figures, 628-9; certain early Greek
logicians mentioned by, who recognized no
major or minor term in the second and
third Figures, 629-30; (and Herminus),
quoted on figure of syllogism, 633-6.
Alexander de Ales, or Alepsis, held the
law of Contradiction I0 be the primary
principle of knowledge, 66; but, in fact,
identified it with that of Excluded Mid-
dle, ib.
86
AlStkdius, on the principle of Contradic-
tion,63; partially anticipated Lambert in the
use of parallel lines as logical notation, 180.
Alvarez, 326.
Ammonius Hermi.*, referred to on genus
of Logic, 7, 89; on the principle of Contra-
diction, 63, 135, 160, 172, 196, 240, 278; re-
ferred to on the \6yos btpi^tav, or reaper,
331, 333, 336; relerred to on Division and
its various kinds, 350; referred to on Greek
article, 531; quoted on quantification of
predicate, 546, 549-51; quoted on Hypothet-
ical (Conjunctive) and Disjunctive Syllo-
gisms, 613-16; (and Philoponus), their
ground of the discrimination of major
and minor terms in the second and third
Figures, 628.
Analogy, what, 450-51, 453-4; founded on
the principle of Philosophical Presumption,
451 ; its agreement with and distinction
from Induction, ib.; has two essential con-
ditions, 454-5; summary of the doctrine of,
455; Induction and Analogy compared
together, ib.; these do not atTord absolute
certainty, 455-6; authors referred to on,
456.
Analysis, see Method.
Analytic, name employed by Aristotle to
denote a particular part of Logic, 6.
Anaximenes, of Lampsacus, the treatise
Rhetoric to Alexander attributed to, 278.
Ancillon, Frederic, refierred to, 32.
Andreas, Antonius, the first to explicate
the law of Identity as a coHrdinate princi-
ple, 65.
Anschauunq, expresses what is common to
Perception and Imagination, as opposed to
Conception, viz., the individuality and im-
mediacy of their objects, 90-1, 129; can bu
translated into English only by Intuition,
but ambiguously, 90-1-
Antholwjia Gr^ca, 280.
'Atrapi^/jLtjcris, its character and meaning, 351.
682
INDPX.
Apodeictic, employed by Aristotle to denote
a particular part of Logic, 6.
Apophantic, see Judgments, Doctrine of.
^Air6<pav(rts, its use by Aristotle, 159.
Applied Logic, the expression, liow employed
by Kant, 43; can only with propriety be
used to denote Special or Concrete Logic,
and is improperly employed as a designa-
tion of Modified Logic, 43,4^
APtTLEius, 296.
Aquinas, St. Thomas, 42; referred to on
classification of the Categories, 141; his
definition of truth quoted, 378.
Arabian Schoolmen, viewed Logic as a
science, 7.
'Apxh TVS yydaeus, distinguished by Aris-
totle from the apxh Tiys ytyfiTfus, 66-7.
Argument, properly denotes the middle no-
tion in a reasoning, 196; Itow defined by the
Latin Sfa^ericians, ib. ; oft«u entployed as
coextensive with argumentation, ib.
Arjstotklic questions, ^n iii, etc., referred
to, 445.
Abibtotelians, ancient Greek, denied Logic
to be either science or art, 7 ; their views on
the object-matter of Logic, 19, 20.
Aristotelians, modern, many of them
maintained Logic to be an art, 7.
Aristotle, quoted, 4; his employment of
the term Dialectic, 6; did not define Logic,
7; his relation to views of the nature and
domain of Logic, 19; by far the greater
number of his logical writings lost, 19 ; none
of his treatises affords a view of Logic from
a central point, ib ; gave no general defini-
tion of Logic, ib.; said that medicine begins
where the philosophy of nature leaves
ofi*, 26; emphatically enounced tlte law of
Contradiction, 62; explicitly enounced the
principle of Excluded Middle, 65; recog-
nized the law of Reason and Consequent,
66; distinguished it from the principle of
Production, 6C-7; said that the doctrine of
Syllogisms deals not with the external ex-
pression, but with the internal reasoning
of the mind itself, 82; see aho 277; used
voiifiaTa in a sense equivalent to concepts.
85; his first anti-prsedicamental ruleqiioted,
103; this rule translated by the Nata nota
est nota rei ipsius, ib.; hie Categories, what,
189, see Categories; noticed the dif1e.rer.ce
of Totential and Actual Wholes, 14<i: i-e-
f'erred to on inclusion of Copula iu prasdi-
cate. 161; called subject and predicate,
the terms or extmnes of a proposition, ib. ;
culled a proposition on IntTval, SitLaTriixa,
ih.; allowed only four kinds of modality,
181 ; described Sub-contrary opposition as
merely in liuiguiigc, 184; se-' aUo 632; his
conversion iv fxtpfi, 186; noticed Conver-
sion per Contrapositionem, under the name
of the inverse consecution from contradictions,
ib. ; his employment of the term fK^tats,
exposition, 185; his expression for Simple
Conversion, 186; his Jna/.v''" are Synthetic,
195; see also 623; his definition of the terms
of a Syllogism, 210; his definition of the
middle, as middle by position, not applica-
ble to the mode iu which subsequent logi-
cians enounce the syllogism, ib. ; but appli-
cable to the reasoning in comprehension,
211 ; did not, however, necessarily contem-
plate the reasoning in comprehension, ib.;
enounced the canons both of Extensive
and Comprehensive reasoning, 214, 243;
his law, — that the whole is necessarily
conceived as prior to the part, — criticized
by the Author, 254-6; only once vaguely
alluded to the process of what was after-
wards called Sorites, 267; his rule translated
■prtKtlicatum pradicati, etc., contains tlje prin-
ciple of Sorites, 268; did not discriminate
the vulgar Entbyroeme as a distinct species
of reasoning, 277; his Enthymeme a syllo-
gism from signs and likelihoods, i6. ,• lihet-
wic to Alexander utiribuied to, 278; the term
axhf^j Figure, due to, 285; distinguished
the first three figiires, 286, 292, 296, 324, 333,
839; his distinction of the two modes of
scientific procedure as from, and to, princi-
ples, 340, 342; his argument for slavery a
petitio principii, 371; referred to and quoted
on knowledge and belief, 383; his precept
regarding the subjugation of self-love,
406, 430, 479; quoted on ability to teach as
a mark of knowledge, 482; first systemati-
cally developed Logic proper, 496; referred
to on postulates of Logic, 512-13; quoted
against quantification of predicate, 546-49;
the true meaning of his esse in toio, and did
de omni, 547-8; his doctrine of predesig-
uation, 548-9; syllogisms in his writings
which are valid only through quantifi-
cation of the predicate, 549, 581 ; his doc-
trine of Induction and Example, 689-93;
ignored the Disjunctive and Hypothetical
syllogisms of the logicians, 603; quoted
and referred to on Hypothetical syllo-
gism. 612-13; his syllogisms ex hypotkesi,
— wtiether correspondent to tlie oniinary
hypothetical syllogism,— nnthoi-s referred
to on, 613; his doctrine of the discrimina-
tion of major and minor terms in the second
and third Figure, 627-8; quoted on Figure
and Terms of syllogisms. 632-3.
Arnaui.d, along with Nicole, author of the
Port Koyal Logic (VArtde Penser),fiO; re-
ferred to as holding that men arc naturally
envious, 408 ; quoted on figure of Syllogism,
641-2.
Arnoldus dk Tdkqbci, his doctrine of In-
duction, 696.
INDEX.
Arbiav, referred to on the argiunent ciUled
Kiyoi Kvpuivv, 33J.
Arsenics, 334.
Akt, aucieiit and modern, diverse ebanu^ers
of, 426.
Association, laws of, what, 419-20.
Association or Suggestion, as a sov^cce oC
ilirror, set Error, «auseii of
Assumption, name for Minor Pitiemise, 201;
but not a suitable term, ib.
Attbntion, the act of, how constituted, 88;
Prescision, Abstraction, and Attention cor-
relative terms, 88.
■ AugustiKj St., his answer to the question
what time is, 118.
Acgustjn, Pscudo, referred to on inapplica-
bility of the categories to Deity, 140.
AUftUSTINCS NiPHUS SUBSSANUS, C3.
AuLUS Gkllius, 331-3.
AVTHKNTiciry, criticism of, see Testimony.
AvERiiOKS, quoted on use of the Arabic
article in quantification. 631-2 ; quoted on
quantification of predicate. .553; quoted on
figure of syllogism, 640-1 ; quoted on fourth
Figure, 662.
AviCEKNA, 451, 454.
Axio.MA,used by Stoics and Bamists as a
synonym for proposition^ 188.
A^iujxa t7js ewTi<paff(a)s, — name applied by
Ammonius and Philoponus to principle of
Contradiction, 63 ; see Contradiction, prin-
ciple of.
Axioms, what, 188.
Bachmann, referred to on the analogy be-
tween Logic and Mathematics, 32, 68, 88, 149,
162, 179, 183, 198, 215, 218, 219, 237, 243, 288 ;
quoted, with brief original interpolations,
on the figures and moods of Syllogism,
28S-302; his reduction of Baroco, 314;
quoted on character of ancient Greek Soph-
isms, 323-4, 3'Jl; quoted on the prejudice
of learned authority, 395-6, 414-17, 428, 440,
45C.
Bacon, Lord, wholly misconceived the char-
acter of Logic in certain respects, 20, 21 ; at
fault in his criticism of Aristotle's doctrine
of Induction, 230; called empirical gen-
eralizations axioms, 367 ; his classification
of the .sources of error, 390; quoted on
reading, 491 ; the aim of his Or^anon, 496.
Ualfour, or Balforeus, referred to on a
spurious passage in Aristotle's Rkeioric, 6 ;
quoted on illustration by the Aphrodisian
of Abstract and Applied or Special Logic,
38; on Abstract and Applied or Special
Logic, 44.
3<^o$) its meaning in relation to concepts,
100.
Baumgabten, a. C, the Leibnitian, the
first to use the terra principium exclusi medii.
65; caUed the principle of Id^itity, prmeU
pium positionis sive identitatis, 66 ; attempted
to demoojatrate the Jaw of Sufficient Set-
son by that of Contradiction, 68, 101 ; quoted
on Canons of Syllogism, 564-S.
Bavn£€(, Tliomas Spencer, his Essay on the
jVew Analytic of Logical Forms referred to,
31; his translation of the Port Koyal Logic
noticed, 60, IW\ Itm Essay referred to,
558.
Begrifp, the term in German philosophy
for the symbolical notions of the under-
standing, 129.
Belief, see Truth and Error, doctrine of.
Ben Gekson, or Gersonides, Levi, quoted «n
quantification of predicate, £54-5.
Beneke, 68; his doctrine of syllogism, 651-2.
B-ertids, 196, 268.
Beza, 280.
BiEL, Gabriul, his use of conceptus, SO.
BiUNDE, 378.
BI.EVMISA8, Nicephorus, 85; referred to on
origin of distinction of propositions jecimt^i
and tertii adj(irentis,l(yi; quoted on import
of the tern* <rvK\oyt(Tfi6s, 197, 274; bis Epit-
ome for many centuries tlie text-book of
Logic in the schools of the Greek Church,
308 ; mentioned as the inventor of the
Greek mnemonic verses for mood and
figure of syllogism, ib.; but, according to
later view, these verses only a translation
of the Latin, ib., 514; quoted on Contingent
Conversion, 521.
BoETHirs, referred to on the application of
the term logic, 4,101,110; his division of
Conversion, 186; the first to give the name
Conversio per accidens, ib. ; nature of this
process as employed by, 186, 198 ; quoted for
use of sumptum and assumptio, 201 ; referred
to on use of terms ponnis and tolUns, in
connection with hypothetical syllogism,
240, 296, 344; quoted on the influence of
passion on the mind, 400, 614; quoted on
quantification of predicate, 551-3.
Bolzano, 240, 244, 456.
Boyle, Hon. Robert, referred to for dis-
tinction of reason in abstraeto, and reason
in eoncreto, 43.
BuANDis, Ch. A., referred to on the title
Organon for the logical treatises of Aris-
totle, 24, 135.
BuANiss, Ch. J., 184, 320.
Breadth and Depth, names for the exten-
sion and comprehension of concepts, 100,
et alibi,
Buchanan, George, 280.
BuFFiER, 112, S44 ; quoted on canons of syl-
logism, 574.
Burgersdyk, or Burgersdicius, referred to
on genus of Logic, 7 ; his Institutionat
LogiccB noticed and recommended, 51, 493;
684
INDEX,
referred to on Whole and Part, 143; quoted
on Potential and Actual Whole, 146, 296.
BUKIDANUS, his sopliism of the Ass referred
to the head of Sophisma Heterozeteseos, 333.
r.URLEiGU, Lord, his practice in reading, 487.
UuTLKR, Samuel, quoted as to the principal
utility of Rhetoric, 35.
(.,'a.ietan, Cardinal, quoted for his use of the
terms intensive and exUtisive in relation to
notions, 101.
Calker, 101.
Camerarius, GuL, referred to on genus of
Logic, 7 ; referred to for scholastic theories
on the object-matter of Logic, 20.
Campbell, Puncipal, quoted on indistinct-
ness of terms, 124.
Capella, Martianus, quoted on figure of
eyllogism, 640-
Caramdel, see Lobkowitz.
Carleton, Thomas Compton, referred to on
the metaphysical character of the Categories
of Aristotle, 141.
Caro, quoted, 407-8, 414, 435.
Cartesiaks, majority of, maintained Logic
to be an art, 7.
Cassiodorus, 279, 640.
CATEaoRicAL Proposition, better styled Ab-
solute or Perfect, 165 ; see Judgments, doc-
trine of.
Categorical, the term, as used by Aristotle,
equivalent to o^rmati'ce, 1C5; its application
by Theoplirastus and Eudcmus, in opposi-
tion to conditional, 1G5 ; this difference of
signification not hitherto observed, 160.
Categories or I'rcdicameuts of Aristotle,
what, 139; original meaning of the term
Category, ib. ; its employment by Aristotle,
130-40; by Plotinus, 140; by Kant, ib.; the
Categories of Aristotle metaphysical, 141 ;
criticized as a classiGcation of being, ib. ;
object.s not included under, 140; diversity
of opinion among logicians regarding their
number, 142 ; various authors referred to
regarding, i6.
Certainty, see Truth and Error, Doctrine
of.
Chacvin, 187.
CiCEUo, referred to on the use of Logica, 4;
probably borrowed ijis use of that term
from the Stoics, ib. ; quoted on the province
of Logic, 26 ; enounced the principle of
Excluded Middle, 65; recognized the prin-
ciple of Ilcasou and Consequent, 67; bis
definition of argumtntum quoted, 196 ; ap-
plied the term Sorites to an argument like
the modern Sorites, but which could also
be a Chrysi/'pean, 268; called the sophism
Sorites Acervalis, ib. ; his employment of
the term Enthymeme, 278 ; his statement of
the Jgnava Ratio, S30, 332-3, 400, 480.
ClECUI.US m demonstrando, see Probation.
Classes, names for the different steps in the
series of, in physical s«ieuce, 142.
Clearmebs and Obscurity, Distinctness and
Indistinctness of Concepts, see Concepts,
Quality of.
Clement of Alexandria, quoted on teaching
as a mean of self-improvement in knowl-
edge, 482-3.
Cleuc, see Le Clerc.
CoGiTATio ( Thought), its use by Descartes, 9;
see Thought.
Cognitive Faculties, Weakness and Dispro-
portioned Strength of, as a source of error,
see Error. Causes of.
Coke, Zachary, his use of the t«rm toneept,
30.
College of Alcale, the, see Cursus Complu-
tensis.
Commcmication of Knowledge, Doctrine
of, see Logic.
CoMPAEisoic, Faculty of, its products three-
fold,— Concepts, Judgments, and Season-
ings, 83; its offices, 87-8.
Comprehension and Extension of Concepts,
see Concepts, Quantity of, and Reasonings.
Concept, should be used to denote the object
conceived, 30; its derivation, t6. ; many
words in English formed on the same anal-
ogy, as precept, digest, etc., ib. ; was in com-
mon use in the sense proposed among the
older English philosophical writers, ib. ;
and among the old French philosophers,
31 ; now employed in French in translating
the German Begriff, ib. ; see also ConcepCus :
what, 54 ; its synonyms, 55 ; see Concepts,
Doctrine of.
Conceptio, its meaning, 85-6.
Conception, employment of the term by
Stewart to denote the simple representa-
tion of an object pre.sented in Perception,
29; vacillation in its use by Reid, i6. ,- sense
in which employed by the author, 30 ; its
derivation, 30; means both the act of con-
ceiving and the object conceived, to. ,- should
be used to denote exclusively the act of con-
ceiving, and concept applied to the object
conceived, t6. ,- Reid quoted on, 78-80; his
mistakes regarding, 80-1; usually called by
the logicians Simple Apprehension, 85.
Concepts, Doctrine of, 83-88 ; of Concepts or
Notions, order of discussion, — A. In gen-
eral, what they are, and how produced, 84
et seq., 93 et seq. ; doctrine of Concepts
omitted by Whately in his Elements, 84 ;
a. Meaning of the terms Concept or Notion,
85-6; their synonyms, 85; Concept denotes
the result of the act of Conception, that is,
of comprehending or grasping up into
unity the various qualities by which an ob-
ject is characterized, 85-6; Notion denotes
INDEX.
685
either the act of apprehending the notes or
marks of an object, or tlie result of that
act, 86 ; employment of the terms animo
vel mente concipere, and animi eonceptus, ib. ;
of concipere, conceptus and conceptio, without
adjunct, ib.; the term Notion, liow employed
by the author, t6.; b. Nature of the thing
expressed, 87 et seq. ; a concept equivalent
to the mediate and relative knowledge we
have of an object, as comprising qualities
or characters common to it with other ob-
jects, 87; nature and production of concepts
illustrated by reference to the history of
our knowledge, 87 et seq. ; the results of
comparison and abstraction or attention, as
operating on objects originally presented in
confused and imperfect perceptions, and
reducing multitude to unity, 87-8; the je-
duction of multitude to unity involved in
conception explained and illustrated, 89 et
seq. ; thought one and the same, while its
contents are identical, ib. ; objects are to us
the same when we are unable to distinguish
their cognitions, whether as wholes, or in
their partial characters, 89; concepts or
notions are constituted by the points of
similarity discovered in objects, and identi-
fied in the unity of consciousness, 90; con-
cepts may themselves become the objects of
comparison and abstraction, 90; concepts
or notions superfluously styled general, ib.;
general characters of concepts, 91 et seq., 96
et seq. ; a. A concept alTords only an inade-
quate knowledge of the thing thought under
it, 91 et seq. ; b. Affords no absolute object
of knowledge, but can be realized only by
being applied as a term of relation to one
or more of the objects which agree in the
point or points of resemblance which it
expresses, (6. ; this doctrine explains the
whole mystery of generalization and gen-
eral terms, ib.; the generality of a concept
is potential, not actual, 92-6; concepts are
not, on that account, mere words, 97; c.
Their dependence on language, 97 et seq. ;
language necessary to the perfection of
concepts, 99; B. Of concepts or notions in
special, 99 et seq.; quantity of concepts, 100
et .leq.; what is meant by saying that a
concept is a quantity, 102; tin's quantity of
two opposite kinds, — Intensive or Com-
prehensive and Extensive, 102-10, see Con-
cepts, Quantity of; quality of Concepts,
111-31, s'e Concepts, Quality of; Recipro-
cal Relations of, 132 et seq., see Concepts,
Reciprocal Relations of.
Concepts, Quantity of, or Comprehension
and Extension of Concepts, wliat, 100-3;
how respectively designated, 100; these
quantities opposed to each other, 103; law
regulating the mutual relations of, 104;
this illustrated, t6. ; processes by which
amplified and resolved, — Determination or
Concretion, Abstraction or Generalization,
Definition, and Division, 102-4; opposed
in an inverse ratio, 105-6; Definition and
Division the processes by which the Com-
prehension and Extension of concepts are
respectively resolved, 106-7; diagram repre-
senting, with relative illustration, 108-10.
Concepts. Quality of. 111 et seq. ; this deter-
mined by their relation to their subject,
111 ; consists in their logical perfection or
imperfection, 111-12 ; this of two degrees, —
Clearness and Distinctness, and Obscurity
and Indistinctness, 112; these degrees dis-
tinguished, ib.; original application of the
expressions, clearness, obscurity, etc., ib.;
illustrated by reference to vision and rep-
resentation, 112-13, 115-16; clearness and
obscurity as in concepts, 113 et seq. ; the
absolutely clear aind the absolutely obscure,
114; distinctness and indistinctness of, ib. ;
liistorical notices of this distinction, ib. et
seq.; due to Leibnitz, 115; notice of Lock©
in connection with it, 114-15; difference
between a clear and distinct knowledge
illustrated, 115 et seq. ; the judicial deter-
mination of life and death supposes the
difference betv»een a clear and distinct
knowledge, 116; further illustration from
the human countenance, ib. ; special condi-
tions of the distinctness of a concept, and
of its degrees, 116-17; the distinction be-
tween clear and distinct knowledge illus-
trated by examples, 118 ; how the distinct-
ness of a concept is affected by the two
quantities of a concept, 118 et seq. ; distinct-
ness is internal and external, 119; relations
of Definition and Division to internal and
external distinctness, ib. ; simple notions
admit of an extensive, individual notions
of an intensive, distinctness, ib.; the high-
est point of the distinctness of a concept,
120; imperfection to which concepts are
liable, in respect of the thought of which
they, are the expression, 121; this imper-
fection illustrated, l'-2 et seq.; noticed by
British philosophers, 123; Stewart quoted
on the subject, 123-5; Locke anticipated
Hume in remarking the employment of
terms without distinct meaning, 125; Locke
quoted on this point, 12&-6; the distinction
of Intuitive and Symbolical knowledge
first taken by Leibnitz, 126; this distinction
superseded the controversy of Nominalism
and Conceptualism in Ccrmany, 126-9; dis-
cussed by him in De Cognitimie, Veritnte, ft
IiJei.t, 127; the passage quoted, 128-9; the
distinction apjjreciated by the disciples of
Leibnitz, 129; Wolfquotcd on. 129-31.
Concepts, Reciprocal Relations of, 132-58;
fN&EX.
relation proper of, whsrt, 132; can be com-
pared together with reference only eiti)er,
1°, To their Extension, or, 2°, To their
Comprehension, ib.; considered, A. As de-
pendent on extension, 132-49; a« dependent
on extension, concepts stand to each*otl>er
in the five mutual relations of Exclusion,
Cbextension, Subordination, Coordination,
and Intersection, 132; examples of the five
mutual relations of concepts, 133-3; dia-
grams illustrative of, 134-; of tliese rela-
tions, subordination and coilrdination of
principal importance, 138; subordination
considered, 133-48; terms expressive of the
diflerent modes of the relation of subor-
dination^ 133 et seq. ; Superior, Inferior,
Broader, Narrower Notions, 135; Univer-
sal, Particular, ib.; General Notion, Genus,
Special Notion, Sijecies. 135-6, «« Genus
and Specie*-; Co<frdiuatiou, what, 14S; the
tM'o general laws by which subordination
and coordination under extension arc regu-
lated, viz., of Homojreneity and Heteroge-
neity, ib ; their import, ib ; law of Hetero-
geneity, true only in theory, ib. ; additional
law of Logical Affinity promulgated by
Kant; but to be rejected, 149; B. As de-
pendent on comprehension, but not in the
relations of involution and coordination,
150-8; notions, in relation to each other,
*re Identical and Different, 150; identical,
divided into absolutely and relatively iden-
tical, ib.; absolutely identical notions im-
possible, ib: ; relatively identical, called also
Similar and Reciprocating or Cun\<ertiblc,
ib ; notions are Congruent or Agreeing,
and Conflictive, 151; Congruent and Iden-
tical notions, and Diverse and Contictive,
distinguished, i6., see Concepts, Opposition
of; Intrinsic and Extrinsic, 153; Involution
and CoUrdination in comprehension. 15S,
155; these relations of notions neglected by
logicians, and hence also neglected rcasan-
ing in comprehension, 153 et .vtj. ; the rela-
tion of the containing and the contained in
comprehension properly called involittion,
155; this illustrated, 156; the involving no-
tion the more complex, the involved the
more simple, 157; coordination in compre-
hension, 157-8; notions coordinated in com-
]>rehension called Disparate, in extension
Disjunct or Discrete, 158.
Concepts, Opposition of, arises under Com-
prehension, 151 ; constituted by conflic-
tion, or the impossibility of being con-
nected in thought, i6. ; twofold, 1=", Imme-
diate or Contradictory ; 2°, Mediate orCon-
trary, (*. ; these distinguished and illus-
trated, 152; their logical significance, 15'J-3;
.v« Opposition, of, Propositions.
CoNCBrTUALis.\t and Nominalism, the whole
controversy originated in the amfoignitj' of
w-ords, 111.97; how to be reconciled, 92; this
question not agitated in- Germany, 97.
CoxcKPTUP i'.s use by IJiel, Occam, 30; Con-
e€f/ius. and corufpttrs animi, its meaning, 86-
CoNCiPKiiK, its meaning, 8ft.
Conclusion, of a syllogism, \Hiat, 198; its
synonyms, ib. ; is the problem stated as a
decision, ib.
CoscKETK or Special Logic, !^e Logic.
CoxDiLLAC quoted on influence of Associa-
tion, 42;i. 454.
CoxDiTiONAL Jirdgment or Proposition, »c
JudfrniL-ntb-. Doctrine of.
CosoiTiONAL and HypotheticnlyXKrintivaKin
regard to the application of the terms,
166-7-; Boethius, used conditionnlis {coni/iUon-
ai) and hypot/uticvt (/n/pni^iftit^)i\s convert-
ible, 167; ronilitional to be applied to the
genus as including h^poihetical and tthjunc-
tire, ib.
CoKFKREKCB, see Knowled)^, DoctrliM' of
the Acquisition and Perfecting" of.
CONFUCIDS, his remedy for precipitntiori, 4D3.
CoNtMBBiCENSES, 184; their error regarding
the opposition of Boethius and Averroes to
Aristotle on quantification- of pr<edieate,
£53.
C0N8PECIH8, what, 148; in so far as they are
considered different, but not contradictor}-,
called Discrete or Dif\)unct Notions, ib.
CoNTiNOKNT Conversion, of the Lower
Greeks, what, 521; Blemnidas cited on, i6.
Contra DICTION, or Non-Contradiction, prin-
ciple of, a- fuudaraentat law of thongtit, 57;
what, 58; properly the law of Non-Contra-
diction, 59 ; how enounced, ib. ; the princi-
ple of all logical negation and distinction,
t6. ; differs IVom the law of Identity only
by a negative expression, 69; its historj-,
62 et seq. ; can be traced back to Plato, 62;
emphatically enounced by Aristotle. 62-3;
with the Peripatetics and Schoolmen the
highest principle of knowledge, ib. : ob-
tained its name from the Greek Aristoteli-
ans, tit.,- said by Ammonins and Philopo-
nus to be the criterion which divides truth
from falsehood throughout the universe of
existence, ib.; said by Suarez to hold the
same supremacy among the principles of
knowledge which the Deity does among the
principles of existence, ib. ; controversies
touching its truth and axiomatic charac-
ter, 6.3-4; its truth denied by modern abso-
lutists, 64; how viewed by Schelling and
Hegel, ib. ; along with that of Identity,
regulateslhe categorical syllogism, 207,251 ;
authors referred to on, 508; conditions of,
ib. ; proof of. attempted by Clauberg^ *. ;
see Puiidamentnl Laws of Thougbti
CoNTDS, Sebastianus, 553.
nSTBEX.
687
Conversion, peritetid»n»,-what, 186; Conver-
sion if fifpfi, not the mere synonym of,
525; differently defined by different logi-
cians, 526; by Boethius, ib. ; by logicians in
general, ih. ; as ampliative, not logical, 520;
as restrictive, fortuitous, or not a conver-
Kion, ib.
CosVEKSiDN, of Judgments or Propositions.
185-8; what, 185; ste oiso 514-15 ; terms em-
ployed to denote the original and converted
proposition, 185; the original proposition
ought to be called the Convertend or Con-
vertible. the product of the conversion the
Converte.il or Converse, 184-6; ste also 514-15,
521-2; species of conversion distinguished
by logicians, 186; (1), Simple or Pure, ift. ,•
(2), Conversio per Accidens, ib. ; this name
first given by Boethius, ib. ; (3); Conversio
per Conti-apositionem, j6. ; divisions of, by
Boethius, ib ; mnemonic -vei-ses for con-
version, 186-7; definitions of, in general,
514-15; a case of immediate inference, ib.;
names for the proposition given in, and its
product, 515; best names lor these together,
Convertent or Converiitif^, and for each apart,
ConvfrlentI and Converse, ib., 522; errors of
the common logical doctrine of, two — first.
That the quantities are not converted- with
the quantified tenns,515-16, 529 ; this wrong
shown, 1°, Because the terms of a proposi-
tion are only terras of relation, 515; 2°,
Only compared as quantities, ib. ; 3^, Quan-
tity of proposition in conversion remains
always the same, 515-16, 525; 4°, Of no con-
sequence logically whether subject or pred-
icate placed first, 516; second error — The
not considering that the predicate has al-
ways a quantity in thought as well as the
subject, 516-20; see also 525-7, 529; only one
species of, and that thorough-going and
self-suflicient, 520 ; conversio per nccidtns, as
ampliative, not logical, and as restrictive,
merely fortuitous, ib. ; see also 526-6, see
Conversion per accidens; Conversio per con-
trapositionem only holds through contradic-
tion, and is independent of conversion, 520,
see Conversion per conUapositionem ; the
Contingent Conversion of the lower Greeks,
not a con\"ersion, 521, see Contingent Con-
version ; advantages of the author's own
method over those of the logicians, 521-2;
the character of, as given by Greek logicians
subsequent to Aristotle correct, 521; errors
of Aristotle and the logicians regarding,
522, 528-9 : authorities referred to on, 527-«. j
CONVKIJSION per conlraposilionem, only holds
through contradiction, and is not properly
a conversion, 620-21, 528; held by some to
be mediate, 520; this erroneous, ib. ; rules
for, 520-1; historical notices of^ and au-
thors referred to on, id.
CoNVERsroN ^v fiepfi, its meaning in Aris-
totle, 525-6.
Coordination of concepts, see Cotcepts,
Relations of.-
COPUI.A, the logical, what, K31-2 ; included
in the predicate by Aristotle; ib. ; styled
the Appredieate, irpotTKaTTiyopoufifvov, 161;
that negation does not belong to, held by
some logicians, 177; the opposite doctrine
maintained by the author, ib. ; true import
of, 177-8; origin of the controversy jegard-
ing tlie place of negation, 178; its msaning
in Comprehensive and- Extensive: proposi-
tions, 193.
CouAx and Tisias, case of, referred to, 334.
Corollaries, what, 188.
CoRViNUS, quoted on inference from pure
particulars, 665.
CocsiN, Victor, his contradictions on the
cognition of tJie Absolute, 61.
Crakanthorpb,162; referred to on names
of propositions in conversion, 186j 229, 261;
his doctrine of Induction, 596.
Crellius, 38, 230, 243, 342.
Crenius, 402, 483i
Criticism, Art of, see Testimony.
Crousaz, 399^ quoted in illustration of pre-
cipitancy, 402-3; quoted on sloth as a source
of error, 404, 430, 435.
Crpsius, Christi&n August, 411 ; quoted on
canons of syllogism, 561-3.
Cv R8US' Complutensis, referred to on induction
of Aristotle, 594.
CuSTOjr, power of, as a source of error, see
Error, Causes of.
D'Abra de Raconis, referred to for scholas-
tic theories of the object-matter of Logic,
20.
Damascenus, Joannes, 5 ; referred to on
method in Logic, 341.
Damiron, his Logique, 50.
David, the Armenian, referred to on thecat-
egoriesi 142.
Darjks, or Daries, 25; referred to on prin-
ciple of SuflScient Reason, 68.
De Morgan, A., Letter of Sir "W. Hamilton
to, 587.
Definite and Indefinite Propositions, as un-
derstood by the author, 171-2, 175, see Judg-
ments, Propositions.
Definition, or Declaration, the analysis of
the comprehension of a concept, 104-6; doc-
tHne of, 341-2; what, ib.: the terms declaration
and definition express the same process in
different' aspects, ib. ,- definition in its strict-
er sense, 342; this explicated, ib ft seq.; va-
rious names of — Declaration, Explication,
Exposition, Description, Definition Proper,
ib. ; Nominal, Real, and Genetic, what,
342-3; rules of, 341; these explained, ib. et
688
INDEX,
seq.; first rule, 844-6; second rale, 345-6;
third rule, 346; circular definition, 346-9;
fourth rule, 346-7; fifth rule, 347-8; Defini-
tion, in its looser sense, 348-; Dilucidations
or Explications, ib. ; Descriptions, 348-9.
Deoerando, Baron, 68, 123, 366.
Delariviere, his Logigue, 50; referred to
on definite article in relation to quantifica-
tion, 531.
Dexzinger, Ignatius, referred to on Catego-
ries, 142, 184, 187; quoted on modes of
faUacia sejvius compositi tt dU'isi, 326-7, 333.
Deuodon, David, referred to on Whole and
I'art, 143,215; quoted on quantity of dis-
junctive and hypothetical propositions, 237,
244, 247; held syllogism and enthymeme to
be the same species of reasoning, 276, 289,
291. 311; his method of reducing Camestres
to Barbara, 314; notice of, 559; his polemic
against the special rules of syllogism, 560;
quoted on Induction, 594; his criticism of
the special rules of the figures reviewed,
636-7.
Desca RTE8, quoted regarding the extension
of the terra Thought {cogitatio), 9; quoted on
the means of avoiding error, 388; his
doubt, 393; his precept to doubt all, 898-9;
conditions which modify its application,
399.
Determination, or Concretion, what, lOi-6;
its synonyms, ib.
Dialectic, ancient name (with certain limi-
tations) for Logic, 5; its use by Plato, ib.;
its origin, ib. ; its use by Hegel, 6; by Aris-
totle,— the logic of probable matter, 6;
mistakes regarding the use of the term by
Aristotle, t6. ,- employed in a vacillating
mnnner by the Stoics, 6.
AtoAcKTifrf; X'^P^^ irpayfidroty, equal to Ab-
stract or General Logic, 38, see Logic.
AtaKtKTiKij iv xPV<^fi foi yvfivoffltf trpcey-
IxJltwv, equal to Special or Applied Logic,
38, see Logic.
Dicta de Omni tt de NuUo, the canons of
deductive categorical syllogisms in exten-
.sion, 214; how expressed, ib. ; logicians
who confound the Dictum de Omni with
the Nota Kota;, etc., 575; who make the
Dictum the fundamental rule of syllogism
in general, 575-6, J*e Syllogism; who con-
found or mnkc coordinate the law of Pro-
portion or Analogy with, 576; who restrict
the Dictum to the first figure (immediately),
»/>. ,• who make the Dicta the supreme can-
ons for universal syllogisms, i6. ; who
erroneously suppose Aristotle to employ,
besides the Dictum, the rule of Proportion
as a fundamental law of syllogism, ifc. ; how
enounced by Noldius, 577; by Keu.«ch, i6. ;
by Aristotle, ib ; by Jac. Tbomasius, ib.;
otijeotions to, 678.
Diderot, quoted on memory, 418.
Dilemma, see Uypotbetico-disjunctire sjrllO'
gism.
Dilemmatic judgment or proposition, tee
Judgments.
Diogenes Laertius, referred to on genus of
Logic, 7; attributed the invention of Soph-
ism Sorites to Eubulides, 268, 324, 331-3;
referred to on the Platonic definition of
man, 347, 3G9.
Diagrams of Ammonius. 637; erroneously
referred to Faber Stapulcnsis, it.
Dialogue, 492, see Knowledge, Doctrine of
the Acquisition and Perfecting of.
DiOKVsins of Ualicarnassus, bis employment
of the term enthymeme, 278.
DiONYSics Cato, on teaching as a means of
self-improvement in knowledge, 483.
DiscussioKS on Philosophy, Author's, referred
to for scholastic theories on object-matter
of Logic, £0; on the character of Dr.
Whately's Elements, 21, 22; referred to fer
a later development of the author's doc-
trine on the Logical Laws, 70, 75, 196, 2907;
referred to on history of Latin and Greek
mnemonic verses for Mood and Figure of
Syllogism, 308.
Disjunctive Reasoning or Syllogism, first
class of Conditional Syllogisms, and second
class afiiorded by Internal Form of Syllo-
gism, 231 ; a reasoning whose form is deter-
mined by the law of Excluded Middle, and
whose sumption is accordingly a disjunctive
proposition, either of Contradiction or of
Contrariety, ib. ; either affirmative, consti-
tuting the Modus Ponens. or Modus ponendo
toUens, or negative, constituting the Modus
ToUenSfOT Modus tollendo ponens, ib.; mne-
monic verses for these modes of, ib. ; its
definition explicated, ib. etseq ; a syllogism
with disjunctive major premise is not neces-
sarily a dii'junctive reasoning, 231-2; gen-
eral view of, 232 et seg. ; formula for a syllo-
gism, a. With two disjunct members, ib.;
b. With more than two disjunct members,
233-4; the principle of, 234; the several
parts of, 235; the rules of, 235-6; these
explicated, 236 et seg. ; first rule of, 236;
second rule of, 237; third rule of, 237-8;
the disjunctive syllogism of comprehension
and extension, t6. ; though specially regu-
lated by the law of Excluded Middle, still
the other logical laws /operative in, 252;
may be drawn in all the four figures, 319;
this illustrated, 319-20; its character accord-
ing to author's latest view. 604-5, 612-13,
614, see Hypothetical Reasoning or Syllo-
gism.
Disputation, see Knowledge, Doctrine of
the Acquisition and Perfecting of
Division, the analysis of the Extension of a
INDEX.
689
concept, 105-7; doctrine of, 350-9; division
ill general, wliat, 300-1; of two specifs,
Partition and Logical Division, 351; parti-
tion eitlier Keal or Ideal, 351-2; examples
of these two liinds of. 351; logical division,
what, 352-3; its rules, 353; its cliaracter
and rules explicated, ib. tt seij. ; the end of,
is Distinctness, which involves Complete-
ness of thinking. 354; as many kinds of
possible as there are characters affording
a principle of division, iO.; a universal
noiion tlie only object of, ib.; general prob-
lem of, 354-5; rules of, 353 et seq.; these
classified, 356; those spiingiiig, i.), from
the principle of division, — first, second,
and third rules, 35f!-7; ii.), from the rela-
tions of the diviiling members to the divided
wholes, — fourth and fifth rules, 358; iii),
from the relations of the several dividing
members to each other, — sixth rule, ?6.;
iv.), from the relations of tlie divisions to
the subdivision. — seventh rule, 859.
Doubt or doubting, the art of doubting well
difficult to teach and to learn, 303, <■ e Error,
Causes of, Descartes.
DowxAJi, 330; referred to on Aristotle and
Plato's views of method, SIC'.
Drobiscit,SS; referred to on opposition of
concei)ts, 151 ; on coordination of notions
iu comprehension, 155, 15S, 179, 219, 320,
351.
DUXCAN, William, of Aberdeen, his Logic,
50.
DUNCAX, Mark, 240, 244, 261, 311; reduced
Camestres to Celarent, and Baroco to Ferio
by counterposition, 314.
ExcYCLOPvEDiA Britannica, 81 et nlibi.
Enxoematic. see Concepts, Doctrine of.
"Ej/i/oia, ivv6i]fjia. v6ri,ua, umbijiuous, 85.
K.NTUYMEMK. a syilo;;ism detective in exter-
nal form, 275; the common doctrine of
logicians regarding, ib. ; this doctrine fu-
tile, and erroneously attributed to Aristotle,
276 et seq. ; 1°, Not a special form of rea-
soning, 276; 2^, Distinction of, as a special
form of reasonirhg, not made by Aristotle,
277 et seq.; the enthymeme of Aristotle,
what, ib. ; various applications of the term,
by Dionysius of Halicarnassus, author of
Rhetoric to Alexander, Sopater Apameensis,
Aulus Gellius, Cicero, Quintilian, 278;
denoted, with some of the ancients, a syllo-
gism with some suppres.sed part, as the
Aphrodisian, Ammonius, Philoponus, Pa-
chymcres, Quintilian, Ulpian, Scholiast on
Ilermogenes, it. ,- 3°, Admitting the validity
of the discrimination of the Enthymeme,
it cannot be restricted to a .syllogism of one
suppressed premise, 279; examples of, of
the first, second, and third order, ib. ; epi-
87
grammr.tic examples of, with suppressed
conclusion, 280-1.
Epicheiuk.ma or Eeason-Keudering Syllo-
gism, the first variety of complex syllogism,
what, 259; authors referred to on varia-
tions ill the application of the name, 220;
in Aristotle the term is used for a dialectic
syllogism, ib. : as a polysvllogism compara-
tively simple, 274; may be drawn in any
figure, 320.
Epictetu.'?, 332; fallacies mentioned by, i7;.
Erasmus, his advice to a young man on the
conduct of his studies^402.
Enizzo, Sebastiano, 25.
EuNESTi, 435.
Eitr.OR, .■iee Truth and Error, Doctrine of.
Enaon, Causes, Occasions, and Komedies of,
390 ; Uacon's classification of the sources of,
390; its causes and occasions comprehended
in one or other of four classes, — 1'^, In the
general circumstances which modify the
intellectual character of the Individual; 2^,
In the Constitution, Habits, and llelationsof '
his powers of Cognition, Feeling, and De-
sire; 3^, In Language as an Instrument of
Thought and Medium of Communication;
or, 4°, In the nature of the objects about
which his knowledge is conversant, 393-1;
these considered in detail, £91 et .^eq. ; I.
General circumstances which modify the
intellectual character of the individual, ib.
et seq.; these of two kinds, — 1^, The par-
ticular degrees of cultivation to which his
nation lias attained ; 2°, The stricter associ-
ations, as schools, sects, etc., 391 ; these illus-
trated, 391-400; man by nature social, and
influenced by the opinion of his fellows,
391-2; I'ascal quoted on the power of Cus-
tom, 392; an ingenious philosopher quoted
on the same subject, 392-0; the art of
doubling well difficult to learn and to
teach, 393-4; two general forms of the
influence of example, 394, — (1) I'rejudice
in favor of the Old, 394-5; (2) Prejudice
in favor of the Kew, 895; Prejudice of
Learned Authority, 395-6; means by which
the influence of Society as a source of Error
may be counteracted, 398 (t seq. ; necessary
to institute a critical examination of the
contents of our knowledge, ib. : the pre-
cept of Descartes on this point, ib. et seq.;
conditions which modify its application,
399; a gradual and progressive abrogation
of prejudices all that can be required of
the student of philosophy, ib. II. The
Constitution, Habits, and Reciprocal Rela-
tions of the Powers of Cognition, Feeling,
and Desire, 400; of two kinds, — i. The
undue preponderance of the Affective Ele-
ments of Mind, 400 et seq.; influence of pas-
sion on the mind, ib ; Boetbius quoted oni
690
INDEX.
this influence, ib. ; the possibility of error
limited to Probable Keasoning, 401; the
PuEsions as sources of error reduced to four,
401-2; 1 Precipitancy, 402 et seq. ; Seneca
quoted on, ib. ; Erasmus quoted on, ib. ; il-
lustrations of, from Seneca, Montaigne,
402-3; precipitate dogmatism and Fkepti-
cism phases of the same disposition, 403;
remedy for precipitation, ib.; 2. Sloth, ib. ;
Seneca quoted on, 404; its remedy, ?6. ; 3.
Hope and Kcar, ib. ; how these passions
operate unfavorably on the Understand-
ing, 405; 4. Self-love, including Vanity,
Piide, etc., 406 (t seq.; Aristotle's precept
regarding this passion, ib. ; illustrations
of the ii.fluence of Self-Love on our opin-
ions, 406-7 i Self-Love leads us to regard
with favor the opinions of those to whom
we aie in any way attached, 406; ilale-
branche adduced to this effect, 406-7; this
shown especially when the passion changes,
408; Arnauld holds that man is naturally
envious, ib. ; the love of Disputation, ib. ;
the affections now mentioned the immedi-
ate causes of all error, 409; preliminary con-
ditions requisite for the efliciency of pre-
cepts against the sources of error, 409-10;
rules against errors from the Affections, 410.
Weakness and Disproportioned Strength
of the Faculties of Knowledge, 411-31;
neglect of the limited nature of the Human
Intellect a source of error, 411 tt srq.; (1)
Philosophy of the Absolute, 411-12; (2) A
one-sided view of the linilude of the mind,
412 tisfq.; this illustrated by reference to
the two contradictories, — the absolute com- i
mencement and the infinite nou-com-
moncement of time, 412; the same priHci-
l)lc exemplified in the case of the necessita-
rian argument against the freedom of the
human will, 413; and in the case of the
libertarian argument in behalf of free-will,
ib. ; weakness and disproportioned strength
of the several Cognitive Faculties, as a
source of error, 414 et seq. ; these faculties
of two classes — a Lower and a Higher, ib. ;
A. The Lower Class, i6. et seq.; (1) The
Prcsentative Faculty, of two kinds, t6. ,• a.
External Perception, as a source of error,
ib. et seq.; conditions of its adequate activ-
ity, 415; precautions with a view to detect-
ing illusions of the Senses, and obviating
the errors to which they lead, 415-16; b.
Self-Consciousness, as a source of error.
416 ft «ei?.; this power varies in intensity ac-
cording to time, state of health, and object,
i6. ; (2) Jlemory, as a source of error, 417
tt feq. ; as feeble, 417; as too strong, 417-18;
remedies for these opposite extremes, 418;
(3) The Ueproductive Faculty, of two kinds,
419; a. Uemiuiscence, as a source of error.
ib. ; its undue activity, ib ; its inactivity,
ib.; b. Suggestion or Association, as a
source of error. 419 et seq. ; influence of As-
sociation in matters of Taste, 421; Stewart
quoted on this influence, 421-3; Condillac
quoted on the same, 423: 'S (Jravesandc,
Herodotus, and Justin, referred to on the
same, 423-4; only remedy for the influence
of Association is the Philosophy of tlie
Human Mind, 424-5; (4) Imagination, as a
source of error, 426 et seq ; its necessity in
scientific pursuits, 420; defect in the art of
modern times as compared with that of
ancient, arising from imperfect culture of
imagination, 426-7; errors arising from the
disproportion between imagination and
judgment, 427 ft seq. ; those arising from the
weakness of imagination, 427; from its dis-
proportionate vivacity, ib.; remedies for
these defects, /A. ,• IJ. Higher faculties, 428
etseq.; (5) Elaborative Faculty as a source
of Error, ib. et seq ; error does not lie iu
the conditions of our higher faculties, but
is possible in the a])plication of the laws of
those faculties to determinate eases, 428-9,
defective action of the understanding may
arise from one of three causes; a. Natural
feebleness, b. Want of necessary experi-
ence, c. Incompetency of attention, 429;
(6) Regulative Faculty not properly a
source of error, 430; remote sources of er.
ror in the different habits determined by
sex, age. bodily constitution, education,
etc., ib ; (elected examples of these, — a
one sided cultivation of the intellectual
powers, i6. ; this exemplified in three differ-
ent phases, — in exclusive cultivation, 1.
Of the powers of observation, 2. Of meta-
physics, 3. Of mathematics, 431; Stewart
referred to on the two latter errors, ib. ;
III. Language as a source of error, 432-9;
its general character considered with a view
to show how it becomes the occasion of
error, 432-4; in what sense language is
natural to man, 432-3; difiiculty as to the
origin of language, 433; language has a
general and a special character, 434 ; no lan-
guage is a perfect instrument of thought,
ib.; languages, from their multitude, difii-
culty of tlieir acquisition, inadequacy, am-
biguity of words, are sources of error, ib.;
this illustrated, 4;i5 et .^eq. ; signs nece.«-
sary for the internal o|K'ration of thought.
435; and for itscomnuiijic:;tioi), ih. .- intona-
tions of the voice the only adequate sen-
sible symbols of thought and its commu-
nication, ib ; these inarticulate and artlc-
Blate, 438; the latter constitute Langnng*
Proper, ib.; how this is a source of enor.
ib. : the ambiguity of words the prlnri> rl
source of error originating in. ih. ; two cii-
INDEX.
691
cumstanccs under this head which mutually
p.fTect encli other, 43")-"; the vocabulary of
every laiigunge necessarily finite, and tlie
conscquer.ces of this;. 437 ; words are merely
hints to the mind, 437-8; remedy for error
. arising from language, 438-9; IV. The Ob-
jects of our knowledge a source of error,
439; rules touching the causes and reme-
dies of our false judgments, 439-40.
r.ssExcE, Ksseutials, or Internal Deuomiua-
tioi'.s, what, 153.
I-lSPL-R, quoted ou the distinction of the mat-
ter aiid form of thought, 11; on tlie latter
as the object of Logic to the exclusion of
the former, 11-12; on the laws of thought
an thought as strictly the object of Logic,
12-13; quoted on the distinction of logical
and metaphysical truth. 75-7; referred to
on relation of concepts to their origin as
direct or indirect, 100-1; quoted on the
clearness and obscurity of concepts, 113-14;
quoted on the special cor.ditions of the dis-
tinctness of a concept, 117-18, 119; quoted
on the highest point of the distinctness of a
concept, 120; quoted on the impossibility
of notions absolutely identical, 151 ; quoted
on the agreement and difference of con-
cepts and judgments, 162-3, 174; quoted on
certain ultra-logical distinctions of propo-
sitions, 187-8; quoted on the act of reason-
ing, 189-90; quoted on the general condi-
tions of syllogism, 197; quoted on the form
of syllogism as a ground of its division
into sp.ecies, 203-4 ; on the laws regulating
tlie various kinds of syllogisms, 204, 215;
quoted ou positive and contrary opposition
in a di.«junctive reasoning, 233; on the
principle of the disjunctivesyliogism, 234-5;
on the several parts of the di.>^junctive syl-
logism, 234-5; quoted on the peculiar prin-
ciple of the hypothetical syllogism, 241-2;
quoted on the first rule of hypothetical syl-
logisms, 215-6; on the ground on which the
hypothetical syllogism has been regarded
as having only two terras and two propoti-
tions, 246-7; quoted on relation of syllo-
gisms to each other, 2.58; quoted on Epi-
cheirema and Sorites, 258-9, 323; quoted ou
division in general, 350-2; ou logical divi-
sion, 354-5 ; quoted ou the rules of division,
351-9; quoted on rules of division spring-
ing from relations of dividing members to
the divided wholes, 358; on the relation of
the several dividing members to each other,
359; on the rule of division, — Divisio ne.
Jiat persaUum,Sb9-G0; quoted on the difier-
ences of probations, 364-0; on pure and
empirical probations, 366; quoted on dis-
tinctions of probations from tlieir internal
form, 367-8 ; on probations, under the in-
ternal form, as synthetic aud analytic,
369-70, 380, 385, 442; quoted on experience
and observation, 444-9; quoted on induc-
tion aud analogy, 451, 452, 453; quoted on
sum of doctrine of induction, 453 ; quoted
on induction aud analogy as not airordiiig
absolute certainty, 465-6; quoted on testi-
mony, 456-9, 460; quoted on credibility of
testimony in general, 460-4; on testimony
in special, 461-7; quoted on criticism and
interpretiitiofi, 469-75; quoted on specula-
tion as a means of knowledge, 476-7.
EcDEMUS, referred to on use of the term cate-
gorical,165; his nomenclature of the parts
of the hypothetical syllogism, 241.
EuGENios, or Eugenius, 85, 101, 142; referred
to on the distinction of Potential and
Actual in relation to notions, 14,5-0; quoted
on import of the term crvWoyiaixhs, 197,
198, 230.
EuLEU, employed circular diagrams as logi-
cal Botatiou, 180 ; but not the first, ib.
EuSTACHiCS, referred to ou Method in Logic,
3il.
EUSTRATIUS, 336.
Example, Aristotle quoted on, 591.
Excluded Middle, or Third, principle of, a
fundamental law of thought, 57; what, 59;
its logical significance, 59-60; the principle
of disjunctive judgments, 60 ; its history,
62 et seq. ; can be traced back to Plato, 62,
65; explicitly enounced by Aristotle, 65;
enounced by Cicero, ib. : received tlie ap-
pellation by which it is now known at a
comparatively modern date, probably from
Baumgarten, 65; regulates in conjunction
with that of Reason and Consequent Hypo-
thetico-disjusictive Syllogisms, 204-5; deter-
mines the form of the Disjunctive Syllo-
gism, 231, 252; authors referred to on, 508;
whether identical with law of Contradic-
tion, ib. ; whether a valid and legitimate
law, 50S-9; see Fundamental Laws of
Thought.
Exclusive and Exceptive Particles, what,
and their effect as indirectly predesignating
the predicate, 517; authorities referred to
on, 518; .ife Propositiones Exponibiles.
ExPEKiEKCE, Sfe Knowledge, Doctrine of the
Acquisition and Perfecting of.
Experiential or Experimental Proposi-
tions, what, 188.
Facciolati. 135, 139; quoted on the mean-
ing and distinction of categoricum, vagum,
and trnnacenilens, 140; referred to on Cate-
gories, 142 ; referred to on Whole and Part,
143, 160, 193, 219, 260, 261, 268, 330, 331, 369;
quoted on Induction, 595.
Fallacies, what, 321; of two kinds, — Pa-
ralogisms and Sophisms, ib. ; this distfno-
tion not of strictly logical import, 223; but
692
INDEX,
not without logical value, ib. ; divided into
Formal, Material, and those at once Formal
and Material, ib. ; Material, lie beyond the
Jurisdiction of Logic, ib. ; Ancient Greek
Sophisms, their character, 323-4; consid-
ered in detail in as far as they lie within a
single syllogism, 325 ft seg. ; I. Formal Fal-
lacies. Categorical, 325-7; first subordinate
Class, — those consisting in quattrnione Ur-
tninorum, 325; under this genus are com-
prised three species, 1^, Fallacia sensus
eompositi et divisi, 325-6; modes of this
fallacy, 32G; 2°, FuUacio a dido secundum
quid ad dictum simpltciter, ib. ; 3^, Fnllaeia
figurer, diciionii, 327; II. Material, 327-34;
of two kinds, — 1.) Of an Unreal Universal-
ity, 327-8; 2.) Of Unreal 3Iiddle or Reason,
828; these kinds of, coincide, 328-9; this
fiillacy as dangerous in its negative as 5n its
positive form, 329 ; species of this fallacy, —
1°, Sophisma cum hoc, vel post hoc, ergo propter
hoc, 329-30; 2°, Ignava Ratio, 330-1; the
history of this fallacy, 831; its vice, 331-2;
8°, Sdp/iisma pol'jzeteseos, 332; its various I
designations, ib. ; 4"^, Sophistna hcterozeteseos, j
i6. ,- it-i various narmes, 333 ; its character, i6.,- |
the Litlgiosiis, ib. ; illustrated in the case of i
Protagoras and Euathlus, 333-i ; and in the
parallel case of Corax and Tisias, SSi; -ue
Probation, Doctrine of.
Fear, see Error, Causes of.
Feueklin, referred to on principle of Suffi-
cient Reason, 68.
FtcnTE, placed the law of Identity as the
primary principle of all knowledge, 66.
Figure, of Syllogism, constituted by the
place which the middle term holds in prem-
ises, 281-2, 285; the Four Figures ari.se
from the relative positiui:s of the middle
term, 282; formulic of the Figui-os in Com-
prehension and Extension, ib. : mnemonic
verses for these in Comprehension and
Extension, ib. ; the name trxvt'M, fs«re,
given by Aristotle, 285; the first, on the
prevalent doctrine, not properly a figure,
t6. ,- three figures distinguished by Aristotle,
ib.; fourth uftributod to Ciulen, but on
slender authority, 285, 423; first notice of
Fourth Figure by Averroes, 285; complex
modification of Figure by the Quantity and
Quality of the propositions, or the Mood,
of a reasoning, 286, see Mood of Syllogism;
doctrine of the Figures according to the
logicians, and in Extension alone, 288-302;
symbol by letters of the First Figure, 288;
rules of First Figure, 28S-9; legitimate
moods of First Figure, with circular dia-
grams illustrative of, 289-90; Second Fig-
ure, its symbols, 291: its rules, 291-2; its
legitimate moods, with diagrams, 292-3;
Third Figure, — its symbol, 294; its rules,
294-5; its legitimate moods, with diagrams,
295-8; Fourth Figure,— its symbol, 299;
its rules, 299-300; its legitimate moods,
with diagrams, 300-2; whatever figure is
valid and regular in Extension is also valid
and regular in Comprehension, 302; criti-
cism of the foregoing doctrine of Figure,
ib ft seq ; the Fourth Figure, — repudiated
by the great majority of the rigid Ariiitotel-
ians, 3f)2; logicians not in possession of the
grounds on which this figure may be set
aside, 303; grounds on which tl-.e Fourth
Figure ought to be disallowed, ib. et seq.;
a cross inference possible from Extension
to Comprehcr.sion, and vice versa, 303; this
the nature of the inference in the Fourth
Figure, 304; this proved and illustrated,
804-5; this hybrid inference is, — 1°. Un-
natural; 2", Useless; 3', Logically invalid,
305; general character of the Second, Third,
and Fourth Figures, 307; the last three
figures only the mutilated expressions of a
comjjlex mental proce.es, and virtually iden-
tical with the first, 308-9 et seq. ; this shown
in detail, 310-11. but «;< Mood of Syllogism;
Figure in i-elatiou to Hypothetical, Dis-
junctive, and llypothetico-Disjunctive Syl-
logisms, 318-20; of no account in varying
the S) llogism, 620-7; double conclusion, in
Second and Third Figures, 627-31; grounds
on which it has been attempted to establisli
the discrimination of a major and minor
term in the Second and Third Figures,
627 et seq.: Aristotle, 628; Ammonius and
I'hiloponus, ib ; llcrminus, ib.; Alexander
Aphrodisicnsis, 628-9; Scotus, 629; Men-
dozu, ib.: anticipatory recognitions of the
truth that there is no major or minor term
in the second and third figures, 629-Sl;
by certain early Greek logicians, 629; by
Valla, 629-30; by John Sergeant, C30-S1 ;
historical notices regarding figure of sylio-
gi<m. 632: Ari.stotle, 632-3; Alexander and
Herniinus, 033-0; IMiiloponus (or Ammo-
nius). 037-9; MartianusCapclla, 639-40; Isi-
dorus,640; Averroes, 040-1 ; Melanchthon,
641; Arnauld, 641-2; Gro.«ser.642; Lambert,
643; Platner. 646-7; Fries, 647-9; Iv rug and
lieneke, 649-52; Tithis, 662-8; direct and
indirect moods in lirst and fourth figure,
658; but not in second and third, (4. ,• fourth
figure, — its character, 659; authors by
whom held that fourth figure diifors from
fii-st only by transposition of preni.jcs, ib ;
moods of fourth figure redressed, 659-61;
criticism of fourth figure, 062; authorities
for and against this figure, 662-3.
First Figure, see Figure.
Fischer, 186; referred to on coBrdination of
notions in Comprcliensiou, 155-8.
FlSCHABEU, 486.
INDEX.
693
Fontaine, La, quoted, 390.
FONSECA, r.. 184, 207, 21G, 289, 292, 325; re-
ferred to as against the doctrine of a mate-
rial quantification of the predicate in recip-
rocating propositions, 543.
Formal Induction, see Induction.
Foii-MAL Trutli, see Truth and Error, Doc-
trine of.
FoH.MAL and Material, their distinction, 539-
42.
FoDRTH Figure. .<;'e Figure.
Fkies, 43; on principle of Double Negation,
68, 149, 203. 215, 243, 249, 2G1, 364, 380, 385,
428,435, 450; quoted on Canons of Syllo-
gism, 570-2; quoted on Figure of Syllogism,
647-9.
Fundamental Laws of Thought, order of
their consideration, 57; these tour in num-
ber,— 1. Identity, 2. Contradiction or Non-
Contradiction, 3. Excluded Middle, 4. Rea-
son and Consequent, or Sufficient Keason,
57 ft set}, (but see 61); their history, 62-8,
iw these Laws ; general observations in
relation to, 09 et set/.; these fall into two
cla.«ses, the first class consisting of the three
principles of Identity, Contradiction, and
Excluded Middle, the second of the princi-
ple of Reason and Consequent alone, ih. :
this classification founded, 1°, On the differ-
ence of connection Ijetween the laws tliem-
eelves, 70; 2°, On the diflerence of the ends
which the two classes severally accomplish,
ib. ; two counter opinions regarding the
limits of objective possibility, 71; the re-
fpeotive spheres of the two classes of the''
laws of thought defined and illusi rated, 71
ft se(j. ; to deny the universal application
of the fiist three laws is to subvert the
reality of thought, 71; but this is not in-
volved in the denial of the universal appli
cation of the law of Reason and Ccn-sequent,
72 et seg.: this law shown in general not to
be the measure of objective possibility , 72-5;
by reference to Extension, P, As a whole,
72-3; distinction of positive and negative
thought, 73; this law not the criterion "of
objective possibility shown by reference to
Extension; 2°, As a part, 74 1 3^, I5y reference
to the law of Reason and Consequent itself,
74-5; this law reducible to a higher princi-
ple, 75; summary statement of the spheres
of these laws, 75; the general influence
which the foregoing laws exert on the
operations of thinking, 7.5-7; the highest
criterion of non-reality, but no criterion of
reality, 76; erroneously held to be the posi-
tive standard of truth, ib.; the absolutists
proceed on their subversion, 77; the whole
of these laws operative in each form of
syllogism, although certain of them more
prominently regulate each various form,
251-2; their relations, 506; authors on, in
general, ib. ; of two kinds, — the laws of the
Thinkable, and the laws of Thinking, 507;
that they belong to Logic, ib. ; on order and
mutual relation of, ib. ; by whom intro-
duced into Logic, ib. ; in particular, authors
on, 507; see Identity, Contradiction, Ex-
cluded Middle.
Gale, Theophilus, 326.
Galex, the fourth figure of syllogism attrib-
uted to, but on slender authority, 285, 302;
new logical treatise of, 285.
Galileo, his rebuke of the Professor of
Fadua. 406.
Galluppi, quoted on canon of syllogism,
574.
Gassendi, 330, 332, 338; referred to, on
Method in Logic, .341.
Gellius, see Aulus Gellius.
General or Abstract Logic, see Logic.
Generalization, what, 90; its whole mys-
tery explained, 91, see Concepts, Doctrine of.
Generic and Specific Difference, see Genus
and Species.
Gknerification and Specification, limited
exjjressions for the processes of Abstraction
and Determination, considered in a partic-
ular relation, 135-8; depend on the two
laws of Homogeneity and Heterogentjity,
148; see Genus and Species.
Genetic Definition, see Definition.
Ge\ovesi. or Genuensis, referred to on one
science being the instrument of another. 25;
his Latin Logic noticed, 51, 474.
Gknue.nsis, .<iee Genovesi.
Genus and Species, or General and Special
notion, what and how designated, 1.35-6;
the distinction of, merely relative, 138-7;
the ab.straction which carries up species
into genera, called Generification or Gener-
alization, 136-7; the determination which
divides a genus into its species, called Speci-
fication, 137-8; gradations of genera and
species, and their designations,138; Supreme
. or Most General genus, what, ib. ; Subal-
tern or Intermediate genus, what, ih. ;
Lowest or Most Special species, what, ib. ;
Subaltern or Intermediate species, what,
ib. ; these distinctions taken from Porphy-
ry's Introduction to the Categories, 139; a
genus as containing under it species, or a
species as containing under it individuals,
is called a Logical, Universal, Subject,
Subjective, or Potential whole, 142; an
individual as containing in it species, or a
species as containing in it genera, is called
a Metaphysical, Formal, or Actual whole,
142-3; these distinctions illustrated, 143 et
seq., see Whole; Generic and Specific Dif-
ference, 146-7 ; as contradistinguished from
694
INDEX.
Individual Difference, 147 ; Conspecies,
what, 148; the classification of tilings by
genera and species governed by two laws
— viz., of Homogeneity and of Heteroge-
neity, 148; a third law alleged by Kant —
Tiz., of Logical Affinity or continuity, but
rejected, 149 ; Gcnns and Difference, the
elements of Definition Proper, 342-3.
Georgk of Trebisoud, or Oeorgius Trape-
zuntiu.s, described the process of Sorites,
but gave it no appropriate name, 269.
Gerlach, 58.
Gibbon, his practice in reading, 489-90.
Gleio, Dr., mistook Keid's view of Concep-
tion, 81.
GocLEXius, Rodolphn.o, discovered and sig-
nalized the Kegressive Compreliensive
Sorites. 273; but before him tbia given by
I'acius, 344.
Godwin, quoted on composition as a means
of intellectual improvement, 482.
Goethe, liis estimate of mathematics, 425.
Great Britain, the country in which Logic
has been most generally and completely
misunderstood, 20.
Greek Sophisms, ancient, their character,
823-4.
Grosser, or Groesenu, 26; quoted on fignre
of syllogism, 642.
GUMDLINO, 25.
GUNKER, ib.
Harvey, Gideon, his use of Concpt, 30.
Hekuebord, his Praxis Logica ix-fcrrcd to,
4U3.
Heokl, his employment of the term Dialectic,
6; repudiated the principles of Contradic-
tion and Excluded Middle in relation to the
absolute, 64; rejected the principle of Iden-
tity as applicable only to the finite, 66; a
dying deliverance of, 281
Hbraclitus, quoted, 481.
Herbart, referred to for a complicated the-
ory of Sorites in different figures, 320.
Heudkr, quoted on tendency of the age to
Over-reading, 487.
Hermakn, Gottfried, 280.
Herminus, his ground of the discrimination
of major and minor terms in the second
and third figures, 628; quoted on figure of
syllogism, 533-4
Her-mooenes, 833, 351.
Herodotus, case cited from, illustrating the
power of Association, 424.
IIeteuooeneity. Law of, what, 148-9, see
Genus and Species.
HiBKisMCUS, Thomas, 484.
HiLAiRE, St., 603.
Hinds, Dr., his encomium of the Elements of
Logic of Dr. Wlmtely.21.
UiBFANUS, Petrus, Pope John xx., or xxi.,
or xxii.,'187; author of the Latin mne-
monic verses for Mood and Fignre of Syl-
logism, 308; notice of, ib- ; his Summulct,
for many centuries the text-book of Logic
in the .•schools of the Latin Church, ib.
HoBBES, maintaiued all thought to l)c at bot-
tom a calculation, 197; quoted on the influ-
ence of authority on opinion, 401.
HOCKER. 85.
UoEFBAUKR, 43, 59, 174, 215, 338; quoted oii
canons of syllogism, 456.
IlOLLMAKN, 289, 291, 294, 456.
Uomooeneitv, law of. what. 148, see Genus.
Hope and Fear, .«e Krror, Causes of.
HospiMAN, John, erroneously attributed llie
invention of the Fourth Figure to Scotua,
303.
Human Mind, limited nature of, as a source
of error, iee Error, Causes of.
Hu.ME, David, 84; quoted on indistinctncits
of terms, 123-4; quoted on belief as the
root of knowledge, 3S4.
HcTCiiESON, Francis, quoted ou canons of
syllogism, 5C3-4.
Hypolemma, name for minor premise or
subsumption of a syllogism, 199.
UvpoTHtsis, what, 188, 449-60; its place and
end in scitiico, 450.
Hypothetical Judgment, or Proposition,
see Judgments, Doctrine of.
Hypothktical Iteasoning or Syllogism, the
second class of Conditional Syllogisms, and
third class afforded by Internal Form of
Syllogi.sm, 239; its general character — a
rca.soning whose form is determined by the
Law of Iteason and Consequent, and whose
sumption is thus necessarily an hypu:l.etic:il
proposition, 239-40; of two forms, Ailirm-
■tive or Constructive — modus portent, nnd
Negative or Destructive — modns tolUttx,
239; authors referred to on use of terms
ponens and toUrns, 240; mnemonic verses for
these forms, ib.; authors on, in general,
referred to, i6. ,- its general character expli-
cated, 240 tt seq. ; contains three pioposi-
tions, i6. ; the modus puitins and ntnlus
tolUns illustrated, 241; nomenclature of
Theophrastus, Eudomus, etc., regarding,
ib ; its |)eculiar principle — the Law of
Reason and Consequent, 241 et seq ; this
principle, how variously enounced, 242 ;
why we cannot conclude from the tnith of
the consequent to tlje truth of the antece-
dent, and from the falsehood of the ante-
cedent to the falsehood of the consequent,
ib. ; conversion of to categorical sylIogi.»mH
is, 1°, Unnecessary, 243; 2°, Not always
possible, 248-4 ; authors on the conversion
of, referred to, 243 ; those of one form easily
convertible into another, 244; siiecinl rulou
of, 245 i these explicated — tirst rule, 246 «t
INDEX.
695
»eq ; regulates the general form of, 245:
ground on which it has been regarded as
Jiaving only two terms ui:d two proposi-
tions. 243; this view erroi.eotis, (6. .• — sec-
ond rule, 247; that t)ie fumption is always
delinito, to be understood in a qualified
sen£C, lb.; that the sumption is always af-
firmative, ib.; the subsumption of, 248; —
third rule, /A., «e 602-6; though prominently
regulated by the law of Reason and Conse-
quent, still the other logical laws operative
in, 252; difficulty in connection with, in
regard to the doctrine that all reasoning is
either from whole to part or from the parts
to the whole, stated and obviated, i6. ft
seq. ; antecedent and consequent of, equal
to condition ai.d conditioned, 252-3; hence
the reason or condition must contain the
consequeut, 253; whole and parts respect-
ively may be viewed in thought either as
the conditioning or as tlio conditioned, '254 ;
application of this doctrine to the solution
of the previous dilliculty, 255; not liable
to the affection of li;,'ure, 318; author's later
doctrine of Hypothetical (or (.'onjunctive
and Disjunctive) Reasonings, 598-618; these
reducible to immediate inferences, 698-9,
599-600, eOl-2, 603-4, 605; referred to the
class of Explicafivcs or Conditionals, 599-
600; not composite by contrast to the regu-
lar syllogism, but more simple, 603; only
preparations for argumentation, 603-4, 609-
10; canons of Hyjiotlietical syllogism, 602,
606 ; theory of, regarded as alternatives,
607-12; errors of logicians regarding, 612;
historical notices of, 012-18; Aristotle,
612-13 ; Ammonius llermije, 013-14; Anony-
mous Scholion, and matter relative to,
611-18.
IlYPOTHKTicAL Proposition, application of
the doctrine of a quantified predicate to,
and its result, 512, see Hypothetical Syllo-
gism.
llYPOTHETico-DiSJU>'CTivE or Dilemmatic
Judgment, see Judgments, Doctrine of.
Hypothetico-Dis.juxctivk Syllogism, Di-
lemmatic or Dilemma, third class of Con-
ditional Syllogism and fourth class afforded
by Internal Form of Syllogism, 205, 249 ;
regulated by the laws of Excluded Middle
and of Reason and Consequent in conjunc-
tion, 205; what, 248-9; held by Wallis to
be a negative induction, 249; its character
explicated, ib. ; designations of — ceracinus,
eornuttm, sc, syilogixmus, etc., 249-50; rules
for sifting a proposed dilemma, 250.
Idea, the term, reason why not regularly
employed, and sense in which it is occa-
sionly used by the author, 90.
IDKMTITY, principle of, a fundamental law of
thought, 57; what, ib. ; variously enounced^
ib. ; its logical importance — the principle
of all logical afhrniation and definition,
58; its history. 62 ft f>-q. ; developed last in
the order of time, 62, 65; first explicated as
a Cfjordinate principle, by Antonius An.
dreas, at the end of the 13ili century, 65;
maintained by Andreas against Aristotle
to be the one absolutely first principle, 65,
66; controversy regarding the relative pri-
ority of the laws of Identify and Contra-
diction, 66; called by Wolf principium cer-
titi/rjinis, ib. ; by Baumgarteu jirincipiuni
po.iitionis sive identitatis, ib. : placed by
Fichte and Schelling as the primary prin-
ciple of all knowledge, ib ; rejected by
Hegel, i6.; along with that of Contradic-
tion, regulates the categorical syllogism,
207, 251 ; formally the same with that of
Reason and Consequent, 251; authors re-
ferred to on, 507-8; see Fundamental Laws
of Thought, I'roportion, law of
Imagination, what, 425-6; its necessity in
scientific pursuits, 426; as a source of error,
»6., see Error, Causes of
Immediate Inference, what, 514; cases of,
recognized by logicians. 514 ft seq. ; 1. Con.
version, ift-.-t*? Conversion, 515 ; 2. Equipol-
lence, or, better. Double Kegation, — merely
grammatical, 522; 3. Subalterr.ation, better
Restriction,/*.; this Bilateral and Unilat-
eral. 523; not noticed by logicians that in
suballernation the .•■ome means some at lensi^
ib. ; the two propositions in subalternation
should be called Restringent or Beslrictive,
the given proposition the JiestringentJ, and
the product the Rf strict or Re.'itnrlet/. 513;
logicians have overlooked the immcdiatf
inference of Subcontrariety, 523-4, 53-i;
this called by the author Inlegmiion, f;24,
534; the two propositions in integration
called the Integral or Litegrnnt, the given
proposition the Integmml. and the product
the Integrate, ib. ; tabular scheme of, 535;
Eustachius quoted on, 601; authors referred
to on, ib.: kinds of, ib.; authors by whom
adojjted, ib. ; Immediate I'eremjjtory, and
Immediate Alternative Inference, 601-2 ;
the latter contains five species, embracing
among these the Disjunctive, Hypotheticai,
and Uypothetico-Disjunctive syllogisms of
the logicians, i!>. ; logicians who refer Hy-
pothetical and Disjunctive Syllogisms to,
600.
Impkdiments to thinking. Doctrine of, tee
Logic.
Indefinable, the, what, 105, 107.
Indefinite, the, how distinguished ft-om the
Infinite, 74.
Indefinite Propositions, 171, iee Judgments,
Propositions.
696
INDEX.
iHDETERMniED, the, what, 55, 56.
iMDiviDUAL or Singular Difference, what,
146-7, see Genus and Species.
Individdal Propositions, 171, see Judg-
ments, Propositions.
Individuum sii^natum and Individuum va-
gttm, 547.
Indivisible, the, what, 105-7.
Induction, of two kinds, — Logical or For-
mal, and Philosophical, Real, or Material,
22G, 5S9-90, C97; the views of logicians re-
garding the nature of Logical Induction
erroneous, 22.0; the characlers of Logical
and uf Real Induction, 226-7; canon of
Inductive Syllogism, 227; this equally for-
mal with that of Deductive Syllogism, t6. /
a material induction, how expres.scd as a
formal, ib. : ohjection obviated, 228; for-
mula: for Inductive Syllogisms in Compre-
hension and E.vtension, 228-9: Whately
and others erroneously make the inductive
syllogism deductive, 229; this done before
Whately by Schramm and Wolf, ib. ; doc-
trine of the older logicians regjirding,
correct as far as it goes, 229-30; doctrine of
Imperfect Induction, 230; Bacon at fault
in his criticism of Aristotle's doctrine of,
i6. ,• authore referred to on, in general, ti.,-
Keal or Material, founded on the principle
of Philosojihical Presumption, 450; its agree-
ment with and distinction from Analogy,
450-1; of two kinds, — Individual and
Special, 452; but in the last result all In-
duction is individual, 452; two conditions
of legitimate, 452-3; summary of the doc-
trine of, 453; Induction and Analogy com-
pared together, 455; these do not afford
absolute certainty, 46.5-6; authors referred
to on, 4-56; authors quoted and referred to
on, 589-97; Aristotle, 589-93; example of,
given in the Ors;finnn of Aristotle, probably
not that proposed by the author himself,
690; Aristotle's doctrine of the correct,
692-3; Pachy meres, 593; Ramus, 593-4; De-
rodon, 594; the college of Alcala — their
error noticed. 594; certain vulgar errors
on, releircfl to. 59t-5; Facciolafi, .595; Lam-
bert, ilj.: strictures on Lambert's doctrine,
595; his doctrine adopted by certain subse-
quent German logicians, 596; his doctrine
old, and well invalidated by the commen-
tators of Louvain, ib. ; a similar doctrine
to that of Lambert held by Versor, Ar-
iioldus de Tungeri, and Lambertus de
Monte, i6. ; Crakanthorpe held that Induc-
tion can only be recalled to a hypothetical
syllogism, 693-7; Material, its character.
687.
IMPKRENCE, meaning of the term, 196: dis-
tribution of, 69S-600: its two grand classes,
— Mediate and Immediate, 588; all infer-
ence hypothetic, 598-9 ; authors by whom
this maintained, 59S-9; the distinction of
as Commutative, £.\plicative, and Conipar-
otive, 599-600; Mediate I'eremptory, and
Mediate Alternative Inference, 602.
Ikpinite, its name and notion, 73-4; ex-
pressed by negative terms, 74; how distin-
gubihed from the Indelinite, ib.
lusTRUCTios, its end, 1; methods of writ-
ten and oral instruction different, ib., sex
Knowledge. Dictrine of the Acquisition
and Perfecting of.
IsTEORiTV, Criticism of, see Testimony.
IsTERPRETATiox, or Exegcsis, Art of. «e
Testimony.
Intuition, the term, its meaning, 90; ambig-
uously translates the Ge:'nian Anschauung.
ib. : what, 386, .ve Truth and Error, Doctrine
of.
Iktuitive and Symbolical Knowledge, see
Concepts, Quality of.
Intuitive, the term, sense in which used by
Leibnitz and the continental philosophers,
121.
Involution of Concepts, see Concepts, Belm-
tions of.
ISENDOORN, Gisbert ab, 37-8, 230.
IsiDORUS, quoted on Figure of Syllogism,
640.
Jakob, 456.
Jerome, St., quoted on the snperior effect of
the living voice, 484.
Judoments, Doctrine of, 159-88; a Judg-
ment, what, 159-60; how distinguished from
a Proposition, t&. ; what is implied in judg-
ment, 160; condition under which notions
are judged congruent, 160-1; a judgment
must contain three notions — viz, of Sub-
ject, Predicate, Copula, 161; these con-
stituents illustrated, 162; propositions of
the Third Adjacent, and of the Second
Adjacent, ib. ; concepts and judgments, bow
far they coincide and differ, 162-3; judg-
ments, how divided, 163: I. From the rela-
tion ol subject and predicate as reciprocally
whole and part, judgments are divided into
Comprehensive and Extensive, »6.,- this dis-
tinction founded on the comprehension and
extension of concepts, 1G3-4 ; II. From the
difference in the relation of determination
between subject and predicate, divided into
Categorical, and Conditional, including
Hypothetical, Disjunclive, and Dilemmatic,
166; categorical judgment explained, ib. et
teq.; the term categorical used by Aristotle
in the sense of affirmative, ib. ; in its second
signification, as opposed to conditional,
probably first applied by Theophrastus, ib. ;
in this employment the terms absolute and
perftct t>etter expressions, 166; natura of
INDEX.
697
a categorical judgment, 166; conditional
judgments, 166-71; these comprise three
species, 163; 1. Hypothetical, ib. et seq.;
variations iu regard to the application of
the terms conditional and hypothetical, 166-7;
a hypothetical judgment, what, 167; appel-
lations of its constituent elements, 168; not
composite, JO. ; not convertible into a cate-
gorical, ib. ; 2. Disjunctive, 169 et seq. ; not iu
reality composite, and not convertible into
a categorical, 169-70; 3. Dilemmatic, or
Hypothetico-Disjunctive, 170 et seq. ; indi-
visible, and not reducible to a plurality of
categorical judgments, 170; these various
kinds of judgments may be considered in
reference to Quantity, Quality, and Rela-
tion, 171 ; a. In relation to Quantity, ib. et
seq. ; the Common doctrine of the division
of judgments according to their quantity,
171; the doctrine of tlie author on this
point, 171-2; all judgments are, according
to the author, either Definite or Indefinite,
171; Definite includes Universal and Indi-
vidual judgments, 171-2 ; Indefinite includes
Particular judgments, 172; projjositions are
either Fredesignate or Treindesignate, ib. ;
common doctrine errs by taking into ac-
count only the quantity of the subject,
ib.; these doctrines explicated, 173 et seq.;
Universal judgments, what, ib ; Singular
or Individual judgments, what, ib. ; Par-
ticular judgments, what, ib. ; words which
serve to mark out quantity iu universal,
individual, and particular propositions, ib. ;
distinction of universal and individual
from particular judgments, 173-4 ; cate-
gorical judgments alone, according to the
logicians, admit of all the forms of quan-
tity, 174; this doctrine erroneous, ib.; b.
In relation to Quality, judgments are di-
vided into Affirmative and Negative. 176;
generality of the definition of predication
and of affirmation and negation, as given
by the author, 176; affirmative and negative
propositions, 176-7; that negation does not
beloug to the copula held by some logi-
cians, 177; the opposite doctrine maintained
by the author, 177-8; origin of the contro-
versy regarding the place of negation, 178;
the possibility of enunciating negative prop-
ositions in an affirmative, and affirmative
propositions in a negative, form, the occa-
sion of much perverse reflilement among
logicians, 178-9; negative terms, how desig-
nated by Aristotle, 178; by Boethius, ib.;
by the Schoolmen, ib.; propositiones infinitcp.
of the Schoolmen, ib ; Kanfs division of
judgments into Affirmative, Negative, and
Limitative unfounded, 179; judgments
divided according to their quantity and
quality taken together, into Universal
8b
Affirmative, Universal Negative, Particular
Affirmative, Particular Negative, ib.; these,
how symbolized, ib. ; circular diagrams
illustrative of, 180; division of propositions
into I'ure and Modal, 180-81; this distinc-
tion futile, 181; division of Modal propo-
sitions by logicians as Necessary, Impossi-
ble, Contingent, and Possible, extralogical,
181-2; Whately quoted on this distinction,
and criticized, 182-3; the terms Assertory,
Problematic, Apo'teictic, or Demonstratice in
relation to propositions, explained, 183;
c. By Eelation to each other, judgments
divided into Identical, Different, Relatively
Identical, Disparate, Di.'junct, Subalter-
nant, Subalternate, 183-4; out of Relation
arises the Opposition of judgments, 181;
opposition either of contradiction or of
contrariety, ib. ; Congruent Judgments,
ib. ; Sub-contrary opposition, what, ib. ;
not a real opposition, ib., see Opposition;
conversion of, 185-6, see Conversion ; cer-
tain distinctions of, not strictly logical,
explained — viz., Theoretical and Practi-
cal, Indemonstrable and Demonstrable,
Axioms and Postulates, Theorems and
Problems, Corollaries, Experimental Prop-
ositions, Hypotheses, Lemmata, Scholia,
187-8; .^ee Propositions.
Justin, case cited from, illustrating the
power of Association, 424.
KaKov KopaKos icaKhf io6v, the proverb, its
origin, 334
Kant, 42; his Applied Logic identical with
the Author's Modified Logic, 43; his em-
ployment of the phrase censured, 44, 58, -59,
88, 112; his employment of the term caie-
gory, 140, 170; his threefold division of
propositions as Affirmative, Negative, and
Limitative, groundless, 179-83 ; rejected
Sub-contrariety as a species of opposition,
184, 242 ; his doctrine of Figure borrowed by
the Author, 307; his speculation founded
on the general relations of distance between
the planets, 367 ; his argument from the law
of duty for human liberty, and the exist-
ence of a Moral Governor, valid, 372,456;
quoted on Crusius's supreme canon of Syl-
logism, 561; quoted on Canons of Syllo-
gism, 568-9.
Keckermann, 216, 230. 243, 250, 342. 351, 527.
KlESEWETTER, 174, 243, 469; quoted on can- ,
ons of syll jgism, 572
KlRWATU, Dr. IJichard. 435.
Knowledge, Doctiine of the Acquisition
and Perfecting of, 441, 493; the means of
perfecting knowledge are, in general, two,
— the Acquisition and the Communication
of knowledge, 441; tlic first mean, — the
Acquisition of knowledge, — considered,
698
INDEX.
441 et seq. ; this must be viewed in relation
to the different kind^j of knowledge, which
are two, as of contingent and of necessary
matter, 441-2 ; consists of two parts — acqui-
sition through Experience, and through In-
telligence, 442; in what sense all knowledge
may he called acquired, ib.; I. The doctrine
of Experience, 442 et seq. ; experience of
two kinds, 442; 1. Personal, 442-3; this in
general, what, 443; explicated, ib. et seq.;
common and scieutilic, 444; Observation,
what, li. /* of two kinds — Observation
proper and Experiment, ib. ; pra'Cognita
of, 445 et seq ; First, The object of observa-
tion, 445-7; this fourfold, 445; 1°, What
the phxnomeua are in their individual pe-
culiarities and contrasts, and as under
determinate genera and species, ib. ; 2^,
What the conditions of their reality, 446;
3'^, What their causes, 44G-7; i°. What the
order of their consecution; Second, The
manner of observation, 447-8; 1°, Proper
state of the observing mind, 447; 2°, Con-
ditions of the question to be determined by
observation, 447-8; Third, The means by
which the data of observation are to be re-
duced to system — viz., Hypothesis, Induc-
tion, and Analogy, 449-56, see those words;
2. Foreign experience, 457 tt seq.; this re-
alized through testimony, ib.; testimony,
what, ib. ; oral and recorded, 457-75, ."ee Tes-
timony ; II. Speculation — the second means
of acquiring and iwrfecting knowledge,
475-6; principal distinctions of empirical
and noetic cognitions, 476; III. Communi-
cation — the Inst mean of acquiring and
perfecting knowledge, 478 93; this an im-
portant mean of perfecting knowledge in
the mind of the communicator, 479; man
naturally determined to communication,
and his knowledge of the object of his
thought is thereby rendei-ed clearer, 76. ,•
this fact noticed by Plato, 16. ; by Ari.«tollc,
Themistius, Lucilius, Persius, Cicero, Sen-
eca, 479-80; the modes in which communi-
cation is conducive to the perfecting of
knowledge are two, 480; 1. By reciprocally
determining a higher energy of the facul-
ties, a. Tlirough sympathy, b. Through op-
pasition, 480-81 ; Plutarch, and J. C. Scal-
iger, quoted on the benefits of opposition
and dispute, 481 ; 2. Uy imposing tlie neces-
sity of obtaining a fuller conscionsness of
knowledge for ourselves, 481; influence of
composition and instruction in perfecting
our knowledge, 481-2; Godwin quoted to
this effect, 482 ; and Aristotle, Plato, Sen-
eca, Clement of Alexandria, Dionysius,
Cato, Scho!!i.«tic .Maxims, Vives, Sai.der-
Hon, 482-3; influence of the communication
of knowledge on those to whom it is ad-
dressed, 483 c( seq.; A. Unilateral Commu
uicatiou or Instruction Oral and Written,
483-92; Oral, its advantages, 484-6; a,
Slore natural, therefore more impressive,
484; Theophrastus, the younger Pliny, Vale-
rius Maximus ( ?), St. Jerome, cited to this
effect, ib. ; b. Eess permanent, therefol-e
more attended to, ib. ; c. Hearing a social
act, 484-5 ; testimony of Menage and Varil-
las to tlie advantages of conversation, 485;
reading, a substitute for oral instruction,
its advantages, a. More easily accessible, b.
More comprehensive, c. More permani-nt,
485; itsdisadvantagesasan exclusive means
of acquiring knowledge, 485-C; Written
Instruction, and its employment as a means
of perfecting knowledge, rules for, 486; 1.
Quantity to be read — rule, Kend much, but
not many works, 487 ; testimonies to this
rule by Solomon, Quintilian, the younger
Pliny, Seneca, Luther, Sanderson, Lord
Burleigh, Herder, ib. , end of reading, 488;
2. Quality of what is to be read — lirst rule,
Reud by selection, 16. ,• — second rule. Begin
with the general, 489; Gibbon quoted to
effect of second rule,^ ib. ; —third rule. Study
a science as it is, before proceeding to its
chronological development, 490; — fourth
rule. Read different works on the same sub-
ject, ib.; — fifth rule. Study works which
cultivate the understanding, and also those
which cultivate the taste, 490; 3. Manner
of reading, 491 et seq. ; — first rule. Read
that you may remember, but especially that
you may understand, 491; — second rule,
Seek to compass the general tenor of a
work, before judging of it in detail, ib. ; —
third rule, Accommodate the intensity of
the reading to the importance of the work,
ib. ; Lectio cursoria, and Lectio stainria, ih. '
Bacon quoted on this distinction, ib.,
Johaun Von MUller quoted on the same,
492; — fourth rule. Regulate, on the same
principle, tl^p extracts from the works you
read, ib.; B. Mutual communication, or
conference, 492-3; of two kinds — Dialogue
and Formal Dispute, 492; (1), Dialogue,
16. ,- (2), Disputation — oral and written,
492-3; Academical. 493.
KopPEN, 262.
Kpiffis and Kplueiy, rarely used by the
Greek.-i, and never by Aristotle, as techiiiciil
terms of Logic or of i'sychology, 159.
KiiUG, W. T., referred to on the form of
thought as the e.xclusive object of Logic,
12; on the laws of thought as thought, 13;
referred to for definitions of Logic, 25; re-
terred to and quoted us to Logic being
merely a foimal instrunici.t of the sciences,
26-7; quoted as to the sense in which Logic
can be St vied the Medici He 0/ the iVimi/, 26,
INDEX.
699
32-3; quoted on the utility of Logic as
serving to guard against error, 34, 36,38;
not aware of the original distinction of
Logica doctns and Lo^ica vtens, 42, 43, 56,
67, 59, 60 ; quoted on the distinction of
Keason and Consequent, and Cause and
Effect, 61-2 ; referred to as to Conception
and Reasoning, involving Judgment, 84,
88, 101, 104, 112, 118, 119, 120, 132, 135, 136,
147; quoted on Individual and Singular
Difference, 147, 149, 151 ; quoted on tlie Op-
position of Concepts, 152-3, 160 ; quoted on
the Copula, 162; quoted on Hypothetical
Judgments, 168-9; quoted on Disjunctive
Judgments, 169-70; quoted on quantity of
Hypothetical and Disjunctive Judgments,
174, 179, 184, 188, 203,214, 215; quoted on
the first rule of Deductive Extensive Cate-
gorical Syllogism, 216; quoted on Quaternio
terminorum , 216-17, 218, 219 ; quoted on third
rule of Deductive Extensive Categorical
syllogisms, 219-20, 227; quoted on the first
rule of the Disjunctive Syllogism, 236 ;
quoted on Hypothetical Syllogism in gen-
eral, 241, 242; quoted on the application of
the principle of Reason and Consequent to
tlie Hypothetical Syllogism, 242; quoted on
Ueductiou of Hypotheticals, 243-4; on Con-
version of Hypotheticals from one form to
another, 244-5; quoted on the third rule of
Hypothetical Syllogisms, 248: quoted on
the designations of the Hyjjothetico-dis-
junctive Syllogism, 249-50; on the rules for
sifting a proposed dilemma, 250; quoted on
classes and desiguations of related syllo-
gisms, 258,284, 311, 320, 321; quoted on a
categorical syllogism with four capital no-
tions, 326, 327; quoted on fallacies of an
Unreal Universality, 327-8; quoted on the
Janata Ratio, 330; quoted on vice oi Ignava
Ratio, 331; quoted on Sophisiria polyzeteseos,
332; quoted on character of the Sophisma
lieterozeteseos, 333, 338, 341; quoted on the
constituents of Logical Methodology, 341,
'MS; quoted on Nominal, Real, and Genetic
deliuitions, 343, 344, 345; quoted on tauto-
logical definition, 346-7; quoted on the rule
of definition which requires it to be pre-
cise, 347 ; quoted on the necessity for a defi-
nition being perspicuous, 347-8 ; on defini-
tion in the looser sense, 348-9, 351 ; quoted
against complexity of division, 357-8, 864,
366, 370; quoted on the circle in probation,
372, 373; quoted on the Mulatto Elenchi, 374,
375; quoted on conditions of the adequate
activity of External Perception, 414-15; on
precautions against errors of the Senses,
415-16, 417, 418; quoted on the Laws of As-
sociation, 420, 427, 428; quoted on error as
lying not in the conditions themselves of
the higher faculties, but in their applica-
tions, 428-30, 436; quoted on remedy for
error arising from language, 438-9, 440,
451, 452, 454, 455; quoted on Induction and
Analogy, 455, 458, 459, 469, 478, 486, 493; his
doctrine of Syllogism, 649-51.
La5ibeut,43; employed parallel lines as logi-
cal notation, 180, 230,456; his doctrine of
the ultra-total quantification of the middle
term, 5S4-6; quoted on Induction, 595;
strictures on his doctrine of, ib. ; quoted on
Figure of Syllogism, 642-5.
Lambertus dk Montx, bis doctrine of In-
duction, 596.
Lange, 25.
Lasgius, 484.
Li^KGUAGE, its relation to thought, and the
influence which it exerts on our mental
operatioi s. 98 etseq.; nni:ecessary in cer-
tain mental operations, ib. ; indispensable
in certain other mental operations, and its
relation to these, 98-9 ; has man invented
it? — ambiguity of the question, 432; in
what sense natural to man, 432-3; was the
first language actually spoken the inven-
tion of man, or the inspiration of the
Deity ? 433; the latter hypothesis consid-
ered, ib.; difiBculty of the question, ib. ;
Rousse:;u cited on, ib. ; language has a gen-
eral and a special character, 434; no lan-
guage is a perfect instrument of thought,
434; signs necessary for the internal opera-
tion of thought, 435 ; and for its commu-
nication, ib. ; intonations of the voice, the
only adequate symbols of thought and of
its communication, ib. ; these inarticulate
and articulate, 436; the latter constitute
Language Proper, ib. ; the vocabulary of
any language necessarily finite, 437; words
are merely hints to the mind, 437-8; Lan-
guage as a source of Error, 436, see Error,
Causes of.
Larroque, quoted on canons of syllogism,
572-4.
L'Art DE Penseb {Port- Royal Logic}, 25;
its study recommended, 50, 408; authors of
very nearly took the distinction between
notions as Clear and Obscure, Distinct and
Indistinct, 114.
Latin Schoolmen, viewed Logic as a science,
7; their views as to the object-matter of
Logic, 19-20.
Laurembergius, p., 26.
Laws of Thought, see Fundamental Laws of
Thought.
Le Clerc, 71.
Lectio Cuksoria and Lectio Stataria, 491,
see Knowledge, Doctrine of the Acquisition
and Perfecting of.
Leibnitz, on the principles of Identity and
Contradiction, 64; did not always distin-
00
INDEX.
guisb the principles of Identity and Con-
tradiction, 66; called attention to law of
Sufficient Reason, C7; founded bis philoso-
phy on the principles of Sufficient Reason
and Contradiction (including Identity), »6.;
did not sufficiently discriminate the law of
Causality from tlie law of Sufficient Reason,
xb. : gave various names to the principle of
Sufficient Reason, ib. ; controversy between
and Clarke, on province of Sufficient Rea-
son, ib.; his distinction of Intuitive and
Symbolical Knowledge, noticed, 87; to
him is owing the distinction of Concepts
into Clear and Distinct, 112-14; the first to
take the distinction of Intuitive and Sym-
bolical knowledge, 126; unacquaintance of
the philosophers of this country with the
doctrines of, 127; manner in which he gave
his writings to the world, ib. : his paper
De Cognitione, Verilatf, ct LJeis, quoted from
on Intuitive and Symbolical Knowledge,
121, 456; quoted on canon of Syllogism,
56(^-1; referred to on simplicity of sorites,
274.
Leidenprost, maintained all thought to be
at bottom a culculution, 197.
IjaMMA, name for the major Premise or
Sumption of a Syllogism, 200.
L.EM.\iATA, what, 188.
liEXCoutra'/icloriarum, principiiim Contradieen-
limn, it.s exlen^:ion in the schools, 65.
hoBicowiT^, JoannesCaramuel, 184; referred
to on various kinds of wholes, 351.
LoCKK, John, totally misapprehended the
nature of l.osic, 21; on the principle of
Contradiction, 64; liis real merits in rela-
tion to the dit-'.iiictions of Ideas, the doc
trine of Uefinition, etc., 115; anticipated
iiume in remarking the employment of
terms without distinct meaning, 125; quoted
. on this point. 125-6.
Looic, the first .>^even lectures of the Author's
Metaphysical Course delivered as a general
introduction to the course of, 1; mode In
which its consideration ought to be con-
ducted, i6. ,• system of, consists of two parts,
viz. : — Introduction to the Science, and
Body of Doctrine constituting the science
itiiclf, 3; questions to be answered in the
Introduction to Lopfic, 3 et srq.; I. Defini-
tion of, 3-24, .?(•(? ai<() 496-7 ; the Science of
the Laws of Thought as Thought, 3 tt seq. ;
this definition explained in detail, i6.; (I)
The word Losic, a. Its history, 3 ft .vq.; the
term (\oytKrj) as marking a particular
science not so old as the science it.self, i6. ;
not used in this sense by Aristotle. 3, 4;
according to Boethius. first applied to the
science by the ancient I'eiipatetics, 4; used
in the wide sense by Alexander of Aphro-
dieias, ib.; but previously to Alexander a
common designation of the science, as ap.
pears from Cicero, 4; b. Its derivation
and meaning, from Ao-yoj, signifying both
thought and its expression, 4; this ambigu-
ity favored the rise of two counter-opinions
regarding the object-matter of, 5, 23; this
twofold meaning, how contradistinguished
in expression by Aristotle, 5 ; by others, ib. ;
appellations of the science afterwards called
Logic, ib. ; vacillation in the application of
the term by the Stoics, Epicureans,and other
ancient schools of philosophy, 6; (2) The Ge-
nus of Logic, — whether science or art, 7 et
seq., see also 498-501; a science according to
Plato and the Platonists, but Dialectic with
them equivalent to the Logic and Metaphys-
ics of the Peripatetics, 7; denied to be either
science or art by the Greek Aristotelians
and many philosophers since the revival
of letters, ib. ; a science according to the
Stoics, i6. ,• and according to the Arabian
and Latin schoolmen, ib.; maintained to
be au art in more modern times by many
Aristotelians, the Rami^ts, and a majority
of the Cartesians, ib. ; both science and art,
according to others, t6. ; in Germany, since
Leibnitz, regarded as a science, ib. : the
question futile, 7; errors of Whately on
this point, 7, 8; what is implied in defining
Logic as a science, 8, 9; held by some to
be a science, 498; and either Speculative
science, ib ; or Practical, t6. ; or both
Speculative and Practical, ib.; an art, 449;
science and art, ib. ; neither science nor
art, but instrument, organ, habit, or instru-
ment:tl discipline, (6. ; that, loosely taking
the terms, is either art, or science, or both.
600; that at once science (part «( philoso-
phy) and instrument of philosophy, ib. ;
that question, whether part of philosophy
or not, an idle question, ib. ; that question,
whether art, science, etc., only verbal.
500-1; Eugeuius quoted to this efiect, ib. ;
(3) Its Obji-cf-matter, 9 et .leq. ; a. Thought,
what, ib. ft seq.; in its wider meaning,
thought denotes every Cognitive act, and
even every mental modification of which
we are conscious, ib. ; in the more limited
meaning. Thought (Thought proper) denotes
only the acts of the understanding, Faculty
of Comparison, Elaborative, or Discursive
Faculty, 9-10; in the more limited mean-
ing, Thought is .the object-matter of Logic,
9; objects that lie beyond the sphere of
Logic, i6. ,- b. Thought as thought, what,
10 et seq. ; Matter and Form of Thought,
distinguished. 11; Logic properly conver-
sant only with the Form of Thought, 11 et
seq. ; this shown by a consideration of the
nature and conditions of the thing itself,
11-12; c. Laws of Thought as Thought, 12
INDEX.
701
tt seq. ; these the proper object of Logic,
12-13, see also 14-17; how distinguished from
Empirical or Uistorical Psychology, 17; as
the science of the Laws of Thought as
Thought, is the science of the necessary
Forms of Thought, 17, 1S2-3; necessary
form of thought implies four conditions —
I. Determined by the nature of the think-
ing subject itself; 2. Original ; 3. Universal ;
4. A Law, 17-18; hence the object-matter of
Logic explicitly enounced, in saying that
Logic is the science of the Laws of Thought
as Thought, or of the Formal Laws of
Thought, or of the Laws of the Form of
Thought, 18, see also 28-9; hence analogy
between and Mathematics as both formal
sciences, 31-2: general historical retrospect
of views in regard to the object and domain
of, 18 et seq. ; merit of the author's view of,
ib.; Aristotle's relation to views of the
nature and domain of. 19; views of Greek
Aristotelians and Latin schoolmen regard-
ing, in general correct, 19-20; views of the
object-matter of, in the Leibnitio-Wolf-
ian and Kantian schools, 20; its nature
most completely and generally misunder-
stood in Great Britain, ib. ; in certain re-
spects wholly misconceived by Bacon, 20-21;
totally misapprehended by Locke, 21; gen-
eral character of Whately'.^ EUments nf, ib. ;
his view of the object-matter and domain
of. stated and criticized, 21-23, see Whately ;
II. Utility of, 24 et seq.; Utilities falsely
attributed to, ib. et seq. ; supposed to be an
instrument of scientific discovery, 24; hence
called an Instrument, or Instrumental Philos-
ophy, etc., 24-5; supposed to be the infallible
corrector of our intellectual vices, 25; its
designations on this supposition, ib., 348;
in what respect an instrument of the sci-
ences, 25-6, 32; not properly an art of
discovery, 26, 32; in what sense to be styled
the medicine of the mimi, 26, 32; the laws of,
the negative condition of truth, ib. ; its
utility that of a formal instrument, or mean
by which knowledge, already acquired,
may be methodized into the form nccom-
modated to the conditions of the under-
standing, 33; useful as giving us, to a cer-
tain extent, dominion over our thoughts,
33-4; as supplying, in part, the criterion of
Truth from Error, 34; as invigorating the
understanding, ib. ; as affording a scientific
nomenclature of the laws by which think-
ing is governed, and of the violation of
those laws, 35-6 —III. Its Divisions, 37 e«
seq., see also 49')-7; division of into Natural
and Artificial inept, 33; its Kinds, or Spe-
cies, and Parts, ib. et .':eq. ; 1°, By relation
to the mind, is ObJE'Ctive and Subjective,
— Systematica and Habitualts, 37; both of
these to be proposed as the end of instruc-
tion in, ib.; 2°, By relation to objects, is
Abstract or General, and Concrete or Spe-
cial, 38, see also 497; these kinds of, how
designated by the Greek Aristotelians, and
by the Arabian and Latin schoolmen, 38;
this division of remounts to Alexander the
Aphrodisian, ib. ; his illustration of the dis-
tinction, ib. ; other illustrations of this
division of, 39; General Logic is alone one.
Special Logic is manifold, and part of the
science in which it is applied, 39-40; the
distinction of Logica docens and Logica
utens mistaken by some modern authors,
42; 3^, By reference to the circumstances
under which it can come into exercise by
us, is divided into Pure and Modified, 42
et seq.; I'ure Logic, what, 43; Modified
Logic, what, ib.; nomenclature of Modified
Logic, 43-4; this identical with the Applied
Logic of Kant and others, 43; not properly
an essential part of, 44-5; Conspectus of
the present course of, 45; Formal and Ma-
terial Logic contrasted, 497; division, va-
rieties, and contents of, in detail, 501-6. —
IV. History of, postponed, 48. — V. Bibli-
ography of, ib. ; this shortly noticed, 49-51;
first great division of, — Pure Logic, —
considered, 52-375; Part I., Stoicheiology,
52-334; Section I., Noetic, or of the Funda-
mental Laws of Thougiit, 52-82; in what
aspect Thought is viewed by, 52-3; the true
relations of Logic overlooked on two sides,
76 et seq. — 1. Erroneously held to afford
the positive standard of truth, 76 — 2. Re-
pudiated as affording no criterion of truth
in relation to the absolute by some philoso-
phers, 77; its Postulates, 81, see also 512-13;
of these only one signalized, — To be al-
lowed to state explicitly in language all
that is implicitly contained lin thought, 81,
see also 510; this cannot be refused, 81; is
implied in what Aristotle states of the doc-
trine of Syllogism, 82; Section IL — Ofthe
Products of Thought, 83-334; i. Ennoe-
matic, — Of Concepts or Notions, 8.3-1-58,
.see Concepts, Doctrine of; ii. Apopliantie,
or the Doctrine of Judgments, 159-88, 5e^
Judgments, Doctrine of; on t'.ie supposition
that Logic takes cognizance ofthe modality
of objects, the science can have no exist-
ence, 1S2: iii. Doctrine of Reasonings, 189-
334, see Rer.Fonings, Doctrine of; Part II.
Methodology, Section i. Method in general,
Section ii. Logical Metliodology, 33')-375;
Logical Methodology, what, 335-'J, 340-41:
consists of three parts, — 1°, The Doctrine
of Definition, 2^, Of Division, 3^, Of Pro-
bation, .341; historical notices of Logical
Methodology, tft.,- 1^, Doctrine of Definition,
341-9, see Definition, Doctrine of; 2°, Of
702
INDEX.
Doctrine of Division, 350-69, see Division,
Doctrine of; 3^, Doctrine of Trobation,
360-75, see Probation, Doctrine of ; second
great division of, — Modified Logic, 376-
493; its object, — the conditions to which
thought is subject, arising from tlie empiri-
cal circumstances, external and internal,
under which man's faculty of thinking is
manifested, 376; its problems three, 1^,
Wliat is Truth, and its contradictory oppo-
site, Krror? 2^, Wliat r.re (he causes of
Error and the impediments to Truth, and
what are the means of their Removal? 3^,
What are the Subsidiaries by which Human
Thought may be strengther.ed and guided
in the exercise of its functions ? ib. ; the
first two questions belong to the Stoicheiol-
o.:;y of Modified Logic, the third to its
Methodology, 377; I'art L Modified Stoi-
cheiology, 376-440; Section i. Doctrine of
Truth and Error, 376-96; Section ii. Error,
its Causes and Remedie.x, 397-440, «'« Truth
nnd Error, Doctrine of; Modified Method-
ology, Section i. Of the Moans by which
oiir Knowledge obtains the character of
I'erfcction, — the Acquisition and Commu-
nication of Knowledge, 441-93, see Knowl-
edge, Doctrine of the Acquisition and Per-
fecting of.
LoGicA Doctns, equal to Abstract or General
Logic, see Logic.
LooiCA Uabitualis, see Logic.
LoGiCA Systematica, see Logic.
LoGicA Utfns, equal to Concrete or Special
Logic, see Logic.
Logical Division, see Division.
i^ooiCAL Induction, see Induction.
Logical Laws, see Fundamental Laws of
Thought.
Logical Methodology, *e< Logic.
Logical Perfection and Imperfection of
Concepts, see Concepts, Quality of. .
Logical Truth, see Truth and Error, Doc-
trine of.
Logical Affinity or Continuity, Law of,
alleged by Kant, but rejected by the Author,
149.
Logical Notation, that by circular diagrams
us illustrating propositions, 180; the first
employment of these improperly ascribed
to Euler, ib.; to be found in Weise, i6. ;
that by parallel lines of ditferent lengths
(Lambert's), partially anticipated by AI-
stedius, j6. ,• circular diagrams illustrative
of reasoning, 191; circular and linear, for
Syllogisms in E.vtension and Comprehen-
fion, 214-15; objection to notation by cir-
cles, 214; diagrams, circular and linear, il-
lustrative of the Sorites, 261, the Author's,
for propositions, 529; circular for the same,
ib. ; Lamberfs linear scheme of, criticized,
C67-9; Maass"« scheme of, criticized, 669-70;
the Author's scheme of, — Ko. I. Linear,
070-3; Author's Fclien»e of, — No. II. Un-
(igured and Figured syllogisip, 673; No.
III. Figuied yyllogitm, — table of Syllo-
gistic Moods, in ciicli figure 12 affirmative
and 24 negative, in all 33, 678-9.
Logical (and Dialectical) Beasoning, its
meaning in Aristotle, 4.
Logical terms,cliiefly borrowed from Mathe-
matics, 196, 209 10.
Ao-yi/cis \oyix-fi, how employed by Aristotle,
3, 4; by Alexander of Aphrodisias, 4; by
the subsequent Aristotelians, ib.
A6yos, its twofold meaning, — thought and
its e.xpression, equivalent to the ratio and
oratio of the Latins, 4, 5; the?c meoniflgs
how contradistinguished by Aristotle. 5;
by others, ib. ; K6yos irpocpopiKhs, and
X6yos dy^ieLdf-Tos, probably originated with
the Stoics, ib.
LovANiKNSES, or Masters of Louvain, 289,
291, 294; quoted on quantification of pi-ed-
icate, 555; quoted on error regarding In-
duction, 590, 617.
LcciAN, 331, 333.
LuciLius, 479.
Luther, quoted on Knowledge and Belief,
883 ; quoted on reading, 487.
Maass, Professor, of Halle, his edition of
tlie Prcecepta of Wyttenbach noticed and
censured, CO; in his edition of the Prcecepta
of WytteuLach rever.>;ed tlie aathor's mean-
ing on analysis and synthesis, 338.
Magentinus, 240, 514; variation of histori-
ans as to the age in which he lived, 590.
Magirus, 486.
Maimon, S., referred to on schemes of logi-
cal notation, 667.
Ma.iok proposition, see Premise.
Mako vii Kerek-Gede, Paulus, 42.
Malebkakche, quoted on the influence of
Self-Love, 407-8.
3IANILIU8, quoted, 389,428; quoted on the
nature of experience, 443-4.
Mariotte, referred to for correct doctrine of
the Aristotelic enthymeme. 278.
Masters of Louvain, the, see Lovanienses.
Masters Regent in the College of St. Lau-
rence in Cologne, their doctrine of Induc-
tion, 596.
Material Induction, see Induction.
MATHEMATicALTruth,«« Truth and Error,
Doctrine of
Mauritius, refers to St. Augustin as author-
ity for quotation as to Logic being the
Arx artium and Scientin fcifntinruni, 25.
Mazuuk, quoted on the office of the natural
sciences, 390.
MkimlRS, 392.
INDEX.
703
Melakchthon, 261 ; his doctrine that there
is a greater force in the negative particle
none, not any, than in the affirmative a//,
627 ; this doctrine shown to be erroneous,
/6., 621 ; quoted on Figure of Syllogism, 641.
Menage, 330, 332,333; quoted on the benefit of
Conversation as a mean of Knowledge, 485.
JlKNDOZA, Hurtado de, quoted on proximate
and remote matter of Syllogism, 202, 207;
his ground of the discrimination of major
and minor terms in the Second and Third
Figures, 629.
MfToAij(j/«s, of Aristotle, its probable mean-
ing, 611.
Metaphysics, the Author's Course of Lec-
tures on, the fii-st seven were delivered by
the author as a General Introduction to the
course of Logic proper, 1 ; relerred to, 88
et alibi.
Metaphysical Truth, «« Truth and Error,
Doctrine of.
Method, in general, what, 335-6 ; authors re-
ferred to on, 336; in reference to science,
what, 336-7 ; considered in its integrity is
twofold — Analytic and Synthetic, what,
33G-7; the Analytic, what, 337; the Syn-
thetic, what, ib. ; confusion in regard to
the application of the terms Analysis and
Synthesis, 337-8; authors referred to on this
confusion, 338 ; these counter processes as
applied to the counter wholes of compre-
hension and extension correspond with each
other, 338^ the Synthetic method has been
called the Trogiefsive, and the Analytic
the Regressive, 331) ; these designations
wholly arbitrary and of various application,
339-40; in general. Synthesis has been des-
ignated the Progressive, and Analysis the
Regressive, process, 340.
Methodology, see Logic, Method.
Metz, 456.
MlCR^LlUS, 85.
Minor I'roposition, see Premise.
MlP.ANDULANUS, Jo. Picus, 142.
MiuANUULANUS, J. F. Picus, 230.
Mne.monic Verses, those embracing the dif-
ferent kinds of propositions in reference to
quantity and quality combined, "Asserit
A," etc., 179, 287; author's English metri-
cal version of these, 287; previous English
metrical versions of the same, ib., see also
589; for Conversion, 186-7; for Di.«juncfive
Syllogisms, 231; for Hypothetical Syllo-
gisms, 240; for Figure of Syllogism, 282.
MoDiFiKD Logic, see Logic.
MoLlN^US, quoted on meaning of the Lex
ContraiJictorianim, 65. 230, 243, 336, 338.
MoNBODUo, Lord, quoted en the distinction
of potential and actual in relation to no-
tions, 145-6; his error on this point, 146.
Montaigne, quoted on illustration of Pre-
cipitancy, 402-3; quoted on precipitate
dogmatism and skepticism as phases of the
same disposition, 403.
Mood of Syllogism, doctrine of, according
to logicians, 286 ft seq. ; name for the ar-
rangement of the three propositions of a
syllogism, with designation of quantity and
quality of each, 286; the Greek logicians,
looking merely to the two premises in com-
bination, called these Syzygies, ib. ; in all
sixty-four moods, 287-8: but only eleven
valid, 288; of the six in each tigure, in all
twenty-four, only nineteen useful, ib. ;
these, according to doctrine of author, may
be still further simplitled, ib. ; the doctrine
of, explicated, 287 ft seq. ; the possible com-
binations of premises tested as to their
validity by the general laws of tlie Cate-
gorical Syllogism, 287-8; these laws give
eight possible moods of a legitimate syllo-
gism, 288; these eight moods being further
tested by the special rules of the First Fig-
ure, leave only four legitimate moods in
that tigure — viz., Barbara, Celarent, Darii,
Ferio, 288-9 ; examples with diagrams of
the legitimate moods of the First Figure,
290-91; in the Second Figure there are four
legitimate moods — viz., Cesare, Camestres,
Festino, Baroco, 291-3; examples of these
vi'ith diagrams, 292-3; in the Third Figure
there are six legitimate moods— viz., Da-
rapti, Felapton, Disamis, Datisi, Bocardo,
Ferison, 294-5; examples of these with dia-
grams, 295-8; some ancient logicians made
two moods of Darapti, 295-6; in the Fourth
Figure there are tive legitimate moods —
viz., Bramantip, Camenes, Dimaris, Fesapo,
■ Fresison, 299-300; examples of these with
diagrams, 300-1; what is true of mood in
Extension holds also of it in Comprehen-
sion, 302; Latin and Greek mnemonic
verses for moods — historical notice of,
307-8 ; the Latin due to Petrus Hispanus,
308; the Greek less ingenious than the
Latin, and, according to author's latest
view, probably copied from the latter, ib. ;
reduction of the moods of the Second,
Third, and Fourth Figures to those of the
First, 309-18; direct and indirect moods,—
their principle, 658-9; direct and indirect
moods in First and Fourth Figures, 658;
indirect moods of logicians of Second and
Third Figures, 663-4; these impo.'sible, 664 ;
new moods, 665-7; Author's table of moods,
678-9.
More, most, etc, the predesignations, vari-
ously referred to universal, particular, or
to neither quantity, 586; authors relerred
to on, ib. ; Corviuus, ib.
MuLLER, Johaun von, his practice in read-
ing, 492.
704
INDEX
MuRETtrs, referred to on a spurious passage
of Aristotle's lihetoric, 6.
MtJBMELLitJS, mnemonic verses of, compris-
ing the Ten Categories, 139; bis mnemonic
verses, quoted of objects not included under
the Ten Categories, 140.
MuTATio Elexchi, see Probation.
Necdssitas Consequentiae et Kecessitos Con-
sequeutis, authors referred to on distinction
of, 599.
Xeqatiox, controversy regarding the place
of. 178; negjitive terms, how designated by
Aristotle, Boethius, the Schoolmen, ib. ;
particula injinitans, what, ib. ; propositioms
infinitee, what, ib.
New Analytic of Logical Forms, proposed
Essay by the author on, 509; extract from
Prospectus of, 509-12.
Noetic, set Logic.
NOLDius, 185; referred to, on History of
Fourth Figure, 303; his reduction of Ba-
roco, 314-17; called the mood Bocardo
Dociimroc.
NoMENCLATCRE, Scientific, importance of,
35.
Nominal Definition, see Definition.
?«ON-CoNTRADiCTiON, principle of, see Con-
tradiction.
NON ens logicum, what, 55.
XoTiON. see Concept.
NUNNESIL'8, 3.36, 451.
Objective Logic, see Logic.
OnsERVATiox. see Knowledge, Doctrine of
the Acquisition and Perfecting of
Occam, William, his use of Concepius, 30.
Olberb, his speculation founded on the
general relations of distance between the
planets, 367.
Opision, see Truth and Error, Doctrine of.
Oppositiojn, or Incom]K)Ssibility, of Judg-
ments or Propositions, what, 184 ; either of
Contradiction or of Contrariety, ib.; Sub-
contrary opposition, what, ib.; not a real
opposition, ib. ; this described by Aristotle
as an opposition in language, not in real-
ity, ib. ; distinction between Indefinitude
and Semi-definitudc or Definite indefini-
tude, 533; the author's doctrine of, evolved
out of this distinction, (6.; Subalternation
and Subcontniriety as forms of, rejected,
ib ; Inconsistency introduced, lA. ; Contra-
dictory and Contrary opposition among
propositions of diflTerfnt quality, what, 53-3-4;
Inconsistency among propositions of the
same quality, 533; subdivisions of Contra-
diction, Contrariety, and Inconsistency,
533-4; diffV'ri'nces in Compossibility of the
two schemes of Indefinite and Definite Par-
ticularity, 534 ; tabular scheme of, 535.
ORGAUoif, name bestowed on the collection
we possess of the logical treatises of Aris-
totle, 24; but not by Aristotle himself, lA. ,■
as thus applied, contributed to the errone-
ous supposition that Logic is an instrument
of discovery, lA.
Ovid, quoted, 482.
Fachvmebes, or Pacbymerins, Georgius,
278; quoted on Induction, 593.
Pacius, Julius, 37, 196, 243, 268; gave the
Regressive Comprehensive Sorites before
Goclenius, 273; referred to, on Figure, 285;
quoted on error of phrase petitio principii,
369.
Paralogism, see Fallacies.
Part, see Whole.
Particclau Propositions, 171, see Judg-
ments, Propositions.
Partition, see Division.
Pascal, quoted on the dignity of man as
consisting in thought, 34; quoted on the
power of custom, 392.
Passion, as a source of Error, see Error,
Causes of.
Paul, St., quoted, 399.
TlfpioxV) not used by Aristotle, but the verb
iTfpifXf'i in relation to notions, 100.
Peripatetics, their nomenclature of the
parts of the Hypothetical Syllogism, 241.
Persius, quoted on Chrysippus, as inventor
of the Sophism Sorites, 268; quoted, 272,
479.
Petersen, referred to on history of Catego-
ries in antiquity, 142.
Petitio Principii, what, 369; error of the
phrase, >A., see Probation.
Petrcs a Cornibus, satirized by Buchanan,
Beza, and Rabelais, 280.
Philo, 5.
Piiiloposus, or Grammaticus, Joannes, 89;
on the principle of Contradiction, 63, 196,
207, 240, 241, 278, i:96, 336; referred to on
analysis of Geometry, 339; (or Ammonius),
his definition of conversion, 514; quoted,
on order of Premises, 624-5; quoted on
Figure of Syllogism. 637-9.
Philosophical or Logical Presumption,
principle of, 450; the foundation of Induc-
tion and Analogy, lA.
Philosophy of Common Sense, the, what,
383; well stated by Aristotle, lA.
PiiocYLiDES. Greek epigram by, 280.
Piccartcs, 196.
Platina, referred toon death of Petrus Hia-
panus, 308.
Platner, Ernst, referred lo, on Logic being
a formal instrument of the sciences, 26,249,
456; quoted on Figure of Syllogism, 646-7.
Plato, his use of the term Dialectic, 5, 6; (and
the Platonists) considered Dialectic (>■ «.|
INDEX.
705
Logic and Metaphysics) as a science, 7;
frequently employed tlie laws of Excluded
Middie and of Contradiction, 62-5; his
(alleged) Second Atcibiades spurious, 65; rec-
ognized the law of lleason and Consequent
or Suihcient Reason, 66; employed, in ref-
erence to this principle, the ambiguous term
otTia, 66, 340; guilty of the vice of circidus
in flemonurando, in his proof of the immor-
tality of the soul, 372; quoted to the effect
that man is naturally determined to com-
munication, 479.
Plato, I'seudo, quoted on teaching as a mean
of self-improvement, 482.
Platonists, the, referred to o:i knowledge
and belief, 384.
TlKaros, its meaning in relation to concepts,
100.
Plautus, quoted on the superiority of im-
mediate to mediate testimony, 459.
Pliny, the younger, quoted on the greater
tendency of hearing to rouse the attention,
484; his maxim regarding quantity to be
read, 487.
Plotinus, his employment of the term cntf-
gory, 140: referred to on Categories, 142;
referred to on analysis of Geometry, 339.
Ploucqukt, Godfrey, 43; referred to on Pos-
tulate of Logic, 512; quoted on Conversion,
628; referred to on quantification of predi-
eate, 558; his general canon of Syllogism,
658.
PLUTAncH, 5, 331; cited on the benefits of
opposition, 481.
PoNCius, referred to for scholastic theories
of the object-matter of Logic, 20.
Pope, Alexander, has borrowed from Ser-
geant, G30.
PoRPUYUY, 101,104; quoted on the relation
between the Breadth and Depth of notions,
104, 139; made two moods of Darapti, 296.
PonsoN, Itichard, his imitation of an e\n-
gram of I'hocydides as applied to Hermann,
280.
Port Royal Logic, see L'Art de Penser.
Postulates of Logic, set Logic.
Postulates, what, 188.
Pn.a!DICATUM pra-dicati e.^t etiam prmdicatum
subjecti, the canon of Deductive Categorical
Syllogisms in Comprehension, 214; how
otherwise expressed, ib.
Precipitancy, see Error, Causes of.
Predesionate and Preindesignate Proposi-
tions, what, 172, see Judgments, Proposi-
tions.
Predicate, of a judgment, what, 161 ; in Aris-
totle tlie predicate includes the copula, ib. ;
called the trrm or extreme of a proposition,
ib. : Quantification of, date of its discovery
by author, 510; its results specified, 510-11,
624-7; considered in detail, 516-20; estab-
89
lished, 1°, That the predicate is as extensive
as the subject, 516-17; 2°, That ordinary
language quantifies the predicate so often
as this determination is of importance, 517;
this done either directly, or by Limitation
or Exception, 517-19; 3°, The doctrine of
the non-quantification of, only an example
of the passive sequacity of the logicians,
519; 4°, The non-quautitication of, given
up by logicians themselves, in certain casi-s,
519-20; logicians {but not Aristotle) rs-
serted that in aflSrmative propositions in
which subject and predicate are quantified
to their full extent, the predicate is distrib-
uted in virtue of its matter. 526; logicians
wrong in their doctrine that in negative
propositions the predicate is always dis-
tributed, ib. ; objections to the doctrine of
the quantification of, considered, 539 ft
seq ; I. General, — objections founded on
the distinction of Formal and Material
considered, 539-43; .II. Special, — 1*^, That
it is false, 543-5; 2°. Useless, 545-6; histori-
cal notices regarding quantification of,
546-559; Aristotle, 545-9; Alexander Aph-
rodisiensis, 549; Ammonius Hermia?, 545,
549-51; Boethius, 551-3; Averroe.s 5.53; Al-
bertus Magnus. 553-4; Levi Ben Gerson,
554-5; Masters of Lou vain, 555; Titiua
and Kidiger, ib. ; Godfrey I'loucqUL-t, 558;
Ulrich, 559; authors referred to on the
doctrine that the extension of predicate is
always reduced to extension of su.bject,
559; authors referred to on the doctrine that
predicate has quantity as well as subject,
ib.; references to Aristotle for use of dis-
tributed predicate, ib.
Prejudice, authors referred to on, 894, see
Prelection, Author's Method of, 2; same
as that prevalent in Germany and Holland,
ib.
Premise, Premises, of Syllogism, what. 198,
199, 207; Major and Minor Premise or
Proposition, i6. ,• objections to these terms
as denominations of the propo.sitions of a
syllogism, 200; their designations, ib. ; best
names for are Sumption and Subsuniption,.,.
199-201; order of 624; Philoponus quoted
on, 624-5; instances and authorities for the
enouncement of syllogism with the minor-
premise stated first, 625-6.
Prescision, wliat, 88.
Presentative Faculty, as a source of Error,
see Error, Causes of.
Prevost, 456.
I'rijxary Laws of Thought, .«« Fundamental :
Laws of Thought.
Pri.vum Cognitum, controversy regarding,
156.
Principi^m Contradicentium, sec Lex Contra--
dictoriarum
roe
INDEX.
PnoBATiox. Doetrine of, 360-75; its diame-
ter and elements, 360; these explicated, 3C1
et seq.; terms employed for Probation, —
Ari^umnntatioti, Argument, Demonstration,
l^adint; of Proof, 361 ; in general, what,t6. ;
how distinguished from Syllogism, t6.;
whereon depends the logical value of,
861-2; ground of Proof either tibsolute or
relative, 362; distinctions of propositions
in respect of the general form of a system
of, 361-5; divisions of Probations, 365 ; the
differences of probations depend partly
on their matter and partly on their form,
>6. ; (1) In respect of their Matter, they are
Pure and Kmpirical, 364-6; this distinction
of Probutions not taken into account by
Logic, 337; (2) In respect of their Form this
is Internal and External, 365-6 ; Probations
are, in respect of Internal Form, a. Direct
and Indirect, 366-7; principle of indirect
proof, 367-8; differences ot Indirect or
Apagogical Probations, 368; b. Deductive
and Inductive, 365-8; c. Synthetic and
Analytic, 365, 369; in respect of External
form, they are, 1°, Simple and Composite,
2°, Perfect and Imperfect, 3^, Regular and
Irregular, 365-6; (3) In respect of their
Degree of Cogency, they are, 1°, Apodeictic
or Demonstrative and Probable, 366; 2^,
Universally and I'articularly Valid, ib. ; the
formal legitimacy of, determined accord-
ing to the logicians by live rules, 369-70;
these rules reduced to two, 370; the five
rules explicated, 370 H serj. ; first rule. Noth-
ing is to be begged, borrowed, or stolen,
869-71 ; its violation affords the Pttitio Prin-
cipi't, 339; limitation under which this rule
is to be understood, 371; second rule, That
no proposition is to be employed as a prin-
ciple of proof, the truth of which is only
to be evinced as a consequence of the prop-
osition which it is employed to prove, 3'j9-
72; its violation affords the vice of vtrrtpov
itp6T(povy 339; third rule. That no circular
probation is to be made, 369-72; its violation
affords the vice of Cimdus in demonstramlo,
369; regressive and progressive proofs not
to be confounded with the tautological cir-
cle, 373; fourth rule. That no leap, no hia-
tus must be made, 370-73; its violation af-
fords the vice of Snltus in demonstrnmlo,
370,373; fifth rule, The scope of the proba-
tion is not to be changed, 370-4; this rule
admits of three degrees, 374; (1) Mutatio
EUnehi, 374; (2) Proving too little, t6. ; (3)
Proving too much, 375.
Problem, the, what, 198.
Problemb, what, 188.
PnocLua, referred to on Knowledge and Be-
lief, 384.
Pbooressive Method, see Method.
Proof, sre Probation.
Proportion, Analogy or Identity, law of,
as a fundamental rule of syllogisms, 575;
made by some logicians the one supreme
canon of syllogism, i6.; logicians by whom
this law is confounded, or made coordinate
with the Dictum de Omni, ib. ; names
given by logicians to, ib. ; erroneously
supposed to be employed by Aristotle as a
fundamental rule of syllogism, 676; terms
under which enounced, 575-8 ; Syrbius
thought that this law, unless limited, is
false, 577, see Syllogism.
Propositio Conrfitionnlis nihil ponit in esse,
the rule, its origin, 169.
Proposition. The, name for major premise,
200; but ambiguous, 200-1.
Proposition, what, 159; ius synonyms, 159-
60; called by Aristotle an interval, Sida-rv/JM,
l''l ; how divided by the logicians, in resp)ect
of quantity, 171; propositions distinguished
by the author into Predesignate (Defi-
nite), and Prcindesignate (Indefinite), ac-
cording as their quantity is or is not marked
out by a verbal sign, 172, see Judgment^
distinctions of, in respect of the generaV
form of a system of proof, 362-3, see also 187
et seq. ; terms of, only terms as terms of a
relation, 615; these only compared as quan-
tities, ib. ; of no consequence logically
whether subject or predicate of be placed
first, 516, 527; in common language predi-
cate often placed first, 516; simply an equa-
tion of two notions in respect of their
extension, 525, 526-7, 528-9; new preposi-
tional forms resulting from the doctrine of
a quantified predicate, 529 et uq., see also
637; these, with the old, in all eight, 529-
30, 534-6; their literal symbols, 629-30;
their notation, ib. ; quantity of, 530 et seq.;
Indefinite propositions (of the logicians),
better Indesignate or Preinrlesignate, ib.; va-
rious opinions as to their cla.'sification, ib. ;
authors referred to on this subject, 530-31;
prevalent uncertainty in regard to Particu-
larity and its signs, 531 ; two meanings of
some, either Semi-definite, and equivalent
to liome only, or Indefinite, and equivalent
to some at least, ib. ; how these may be sym-
bolized, 632; Aristotle and logicians recog-
nized only the latter of these meanings,
631-2; reasons of this, 532-3; Dcfinitudeor
Non-particularity of three kinds, 531-2;
how these forms maybe symbolized, i6. ;
effect of the definite article ond its absence
in different languages in reducing the defi-
nite to the indefinite, 531; to what the In-
definites of Aristotle correspond, 632; logi-
cians who have marked the quantities by
definite and indefinite, 532 ; the three pos-
sible relations of the terms of, 1. Toto-total
INDEX,
• 707
covnclusion, 2. Toto-total coiixclusion, 3.
Iiicoinjjietc coinclusion, involving Incom-
plete coixclusion, 633; the whole order of
best and uort-t quantification of the terms
of, throu^liout the two qualities of Affirma-
tion and Kegatiou, 537-39, see Judgments,
Doctrine of.
I'ROPOSITIOXES tertii arljactntis, or tfrtii ad-
jecti, what, 102; liow designated by the
Greeks after Aristotle, 161-2 ; secundi atlja-
centis, what, 1G2.
ruoposiTiONES Exponibiles, the doctrine of,
iis given by logicians, 018-10, see Exclusive
and Excejjtive Particles.
ripoffATji^ts, of Theophrastus, its probable
meaning, 611.
l\p6Taais, its use by Aristotle, 159.
I'RUTAOOUAS and Euathlus, the case of,
quoted, 334.
ruovERBS, The Book of, cited, 480.
I'SKLLUS, Michael, the Synopsis of the Orga-
non atti'ibuted to, in all probability a trans-
lation from llispanus, 308.
I'SYCHOLOGY, Empirical or Historical, how
distinguished from Logic, 17, 22.
ruKCUOT, rel'erred to on Categories, 142)
mnemonic verse for Disjunctive Syllogism,
from, 231 ; his formula for the Figure of
Syllogism (in Extension), 282; referred to
on the predesignation of the predicate by
nil collectively, 559.
I'UKE and Applied^ as usually employed in
opposition in Olerman philosophy, not
proiK-'rly relative and correlative to each
other, 44; pure and mixed, applied and un-
applied, properly correlative, (6.
Pure and Modal Propositions, 180-81, see
Judgments.
PuilE Logic, see Logic.
Qualities, or Modes, what, 55; their syno-
nyms, 55.
QuiNTiLiAN, 260; his employment of the
term Eiuiii/meme, 278, 332; his maxim re-
garding quantity to be read, 487.
Rabelais, 280.
Hamists, maintain logic to be an art, 7.
Kamus, referred to on genus of Logic, 7, 142;
his illustration of the distinction between
Abstract or General, and Concrete or
Special Logic, 39; referred to on Method in
Logic, 341; relierred to on postulate of
Logic, 512; quoted on Induction of Aris-
totle, 593-4.
Rapix, referred to on canon of syllogism,
500.
Reading, see Knowledge, Doctrine of the
Acquisition and Perfecting of.
Real Definition, see Definition.
Rbal Induction, see Induction.
Real Truth, see Truth and Error, Doctrine of
Reason and Consequent, Law of, ste Suffi-
cient Reason.
Reasoning, see Reasonings, Doctrine of,
Syllogism.
Reasonings, Doctrine of, 189-334; the act of
Reasoning, what, 189-90; this illustrated by
an example, 190; the example given is a
reasoning in the whole of Extension, and
may be represented by three circles, 191;
the reasoning of E.xtension may be exhib-
ited in Comprehension, 191-3; the copula
in extension and comprehension of a
counter meaning, 193 ; definition of the
process of Reasoning with the principal
denominations of process and product,
193-4; these explicated and illustrated, 194
ft set/. ; 1. The Act of Reasoning, — a rea-
soning is one organic whole, ib. ; errors of
logicians ou this point, 195; utility of the
process of reasoning, ib. ; 2. Terras by
which the process of reasoning is denom-
inated, — Heasoning, Ratiocination, Dis-
course, Argu7nentation, Argument, Inference^
To conclude. Conclusion, To syltogizf, CoUee-
tio, Colligere, 195-7; general conditions of
Rea.soning or Syllogism, 197, see Syllogism;
reasoning may proceed in the quantity of
Extension, and in that of Comprehension,
207 et seq. ; reasonings in these opposite
quantities explicitly compared and con-
trasted, 209 et seq. ; logicians have over-
looked reasoning in Comprehension, and
have thus given narrow and erroneous defi-
nitions of the major, middle, and minor
terms, 209-10, «e also 153 et seq. ; difficulty
in legai-d to the doctrine that all reasoning
is either from the whole to the part, or
from the parts to the whole, stated and ob-
viated, 252, see Inference, Syllogism.
Reciprocating Propositions, common doc-
trine of logicians that predicate in these
quantified vi »nn«eri«, 526, 542, 544; this in-
correct, 544 ; authors referred to who hold
that they may be simply converted, 528;
Pacius, Alexander Aphrodisiensis referred
to on, ib. ; Fonseca cited against their
quantification vi mattritr., 543.
Rkui, his anecdotes of two Peripatetics, 407.
Reduction of Syllogisms, the whole of the
rules given by logicians for, unphilosoph-
ical,308; these superseded, 809-18; reductio
ad impossibile applied to Baroco and Uocar-
do. but awkward and perplexing, 312, 314.
REGRESSn'E Method, see Method.
Reid quoted on Conception, 78-80; his mis-
takes regarding, 80, 81; not, however, opc«
to Dr. Gleig's censure on this point, 81.
Reimaiius, U. S-, anecdotes cited from, of
the intlucnce of passion on opinion, 407;
quoted ou canons of Syllogism, 565.
t08-
INDEX.
^EixnoLD, 370.
■IKeminisckncb, as a source of Error, see Er-
ror, Causes of.
■Eep RESENT ATION {repreientatio), the term,
sense in wliicli it lias been used on the
'•Continent since the time of Leibnitz, 90;
want in English of a term to express what
Is thus (improperly) denoted by represen-
'lation, ib.; Sense in which used by the
autlior, i6.
Eepugnajjce, of Notions, equivalent to Con-
••tradictory Oj)position. 152.
'Bedscu, or Keu.schius, 101, 243, 259, 311; his
'reduction of Baroco, 314, 315. 317, 313, 451,
456; quoted on canons of Syllogism, 501.
■RHKTor.ic to Aleximder, author of, his employ-
ment of the term tnthymeme, 278.
EiciiTKii, ileinricli, referred to, as to Logic
not being properly nn art of Discovery, 20;
quoted on the dominion which Logic gives
us over our thoughts. 33^, 45, 183, 312, 3S0.
^ItlDiOER. 186; noticed the error of those who
make Sorites only of comprehensive whole.
♦270; erroneously attributed introduction of
Fourth Figure to Galen and Scotus, 303:
quoted and criticized on quautitication of
predicate, 555-8; syllogistic forms pro-
pounded by, 557-8.
ROMAONOSI, 51.
•■K()9LINO, 66.
Kous-SEAU, cited on the difficulty as to the
origin of Language, 433.
'Buiz, Didacus, referred to, on history of dis-
•tinction of Sensus Compositi et Divisi, 326,
«7S, 337.
■SALTua in fiemimstrando, what, 370-3; only a
' special ou.sc of tlic Petitio Frincipii, 873, see
Probation.
Samdeiison, lUshop, quoted on objects not
included under the ten categories, 140; re-
ferred to on mimes of propo.«itions in con-
version, 185,227; quoted on importance of
teacliing as a mean of self-improvement,
4*^3: his jiractice in reading, 487.
Bauteii, 42; quoted on canons of Syllogism,
666.
Savonarola, quoted on canon of Syllogism,
ScALioER, J. C., quoted on the benefits of
»dijCussion, 431.
ScuEjHLER, 131, 210, 210; quotetl on what
constitutes a Di.xjunctive Koasoning, 232,
240; referred to on Aristotle and Plato's
vii;\vs of Method, 340; rcferre<l to on
Method in Logic, 311,342.458; quoted on
I'ropositioncs Exponibiles, 518-19; referred
to on opposition of Subalternation «nd of
■fiubcontrariety, 532.
8CI1EIDI.EU, 426, 48;;, 490, 492, 493-
SouKLLiNO, repudiated tbc principles of Oon-
tradiction and Excluded Middle in relation
to the Absolute, C4; respect in which his
treatment of the principle of Contradiction
differed from that of Hegel, ib. ; placed the
law of Identity as the primary principle of
all knowledge. 60.
SCUMOLDERS, 451. 454.
ScuoLiA, what, 188.
Scholiast on llermogenci, his doctrine of
the Enthymomo, 279, 334.
SciiOTTUS, Andreas, 334.
ScHRAM.M, made the Inductive Syllogisln
deductive, 229.
SciiULER, referred to for scholastic theories
of tlie object-matter of Logic, 20.
SciiULZE, G. E , 56, 57, 69, 60, 88, 104, 162, 174,
179, 183, 196, 215. 219.
ScHWEinii.<EaBER, 200; referred to on true
reading of Epictetus, 3.32.
Science, definition of, 335-6; its perfection
of two kinds —Formal and Material, 337;
distinguished as Keul and Formal. 380;
under the Keal Sciences are included the
3Iental and Material, 3S0-81; divided into
two great branches, according as it is con-
versant, P, About objects known, or, 2P,
About the manner of ki. owing them, 495-6;
these branches called respectively Direct
Science or Science Simply, and Keflex Sci-
ence, the Science of Science, the Method of
SciLMice. 495; the latter falls into two great
bninches as it is conversant, 1°, About the
laws under which the human mind can
know, or, 2^, The laws under which what
is propo.<ed by the human mind to know,
can be known, 493; the former is Logic
proiHJrly so called, the latter not named, ib. ;
but in its parts, called Hetirflic, Areltitec-
tonie, ib. ; these sciences, res|K'ctively devel-
oiied by Aristotle, and by Bacon, ib. ; not
inconsistent, but correlative and dependent,
ib.
Scotus, John Duns, referred to as to genus
of Logic, 7; referred to for scholastic theo-
ries on the object-matter of Logic, 20; (or
St. Augnstin) quoted as to Logic being the
Ar.t artimn and Sci'titia .<c(>ii«iVirim7. 25, 42,
227,291; alleged as defending the Fourth
Figure, 303; this erroneous, i6,- held Feri-
son, Bocardo, and Felapton as useless, be-
cause concluding indirectly, 318; his ground
of the discrimination of major and miimr
terms in tlic Second and Third Figures,
629.
Second P'igure, .ve Figure.
Seouy. quoted on canons of Syllogism, 567.
Selp-Ix)VE, srf Error, Causes of
Seneca, example of Sorites from, 272, .*»;;
quoted on Division, 357; quoteil on evil
intiuence of precipitancy, 402; quoted on
the hope of dying old, as an illustration«f
INDEX.
TO^
precipitate judgment, 402 ; quoted on sloth
as a source of error, 404, 480; quoted on
teaching as a mean of sell-improvement in
Uuowledge, 482; Iiis maxim regarding the
quantity to be read, 487.
Seegeant, John, notice of, 630; bis doctrine
of the Second and Third Figures, 630-31.
Skxtus Emi'iuicus, 5, 198, 339.
'S G iiAVESANWE, cited ou influence of Asso-
ciation, 424.
SiGWAUT, referred to on what truly consti-
tutes a Disjunctive Keasoning, 234, 334, 344,
375, 390.
SiMPLicius,5; referred to on genus of Logic,
7,65. .
Sloth, $fe. Error, Causes of.
Smiolecius, referred to ou genus of Logic,
7 ; referred to for 8chola.stic tlieories of the
object-matter of Logic, 20, 42.
Smith, Adam, quoted on influence of Asso-
ciation. 422-3.
Smkll, 469, 475.
SooiETY, influence of, as a source of Error,
set Error, Cairecs of.
SoeBATi;9, bis saying regarding the extent of
his knowledge, 393-4.
Solomon, 487. ^
SQI'ATER APAMEENSie, 211.
SoPUls.'tf, &te Fallucies.
SOKITES, or Chain Syllogism, 257-74; the
second variety of Complex Syllogism, 280;
what, ib.; its form.uhc in Comprehension and
Extension, ib. ; Piogressive and Regressive,
260-1; authors on, in general, referred to,
261; diagrams, circular and linear, illustra-
tive of, ib.; concrete examples of, 261-3;
the formal inference equally necessary in,
as in simple syllogism, 263; resolvable into
simple syllogisms, ib.; tliis.illustrated, 263-4;
equally naturaJ as simple syllogism, 204;
may be either Categorical or Hypothetical,
ib.; law8ofthe.se forraus of, 2t)4-5; tbrmula
of Hypothetical Sorites, 265; resolution of
Hypothetical Sorites, progressive and re-
gressive, into simple syllogismf*, 265-G ; a Dis-
junctive Sorites possitile after a sort. 266-7;
but complex and unserviceable, 267; his-
torical notice of the logical doctrine of, ib.
et seq. ; neither name nor doctrine found in
Aristotle, ib. ; but the principle of given in
Aristotle's first antipredieamental rule, 268;
the term sorites never applied by any an-
cient writer to designate a certain form of
reasoning, (6. ,- with them denoted a par-
ticular kind of sophism, ib. ; first used in its
present acceptation by Laurentius Valla,
'.69'; the process of, described in the Dialec-
tic of George of Trebisond, the contempo-
rary of Valla, ib. ; the doctrine of logicians
regarding, illustrates their one-sided view
of the nature of reasoning in general, ib. ;
the Sorites of extension overlooked, and;
that of comprehension, the progressive^
alone contemplated by logicians, 270; dif-
lerence between the two forms of, ib. ; probr.
able reiison why logicians overlooked, ia
the case of Sorites, tJie reasoning in extent-
sion, 271-2; examples of, in comprehension
and extension, 272-3; the Goclenian, or
Kegressive Comprehensive Sorites, 273;
names given to, 273-4; before Valla, called
vaguely complex syllogism, 274; as a poly-
syllogism, comparatively simple, ib. ; may
bedrawm in any figure, 320; observations
on, 619; correction and amplification of
the common doctrine of, 619-21; diagrams
illustrative of, 620-21.
SouiTES, the sophism, its derivation and
meaning, 268; its nature, ib.; said to have
been invented by the Stoic Chrysippus, ib. ;
by Eubulides, ib. ; called (paXaKphs, calvus,
ib. ; called acervalis by Cicero, ib. ; its char-
acter, 332; itfi various designations, ib.;
well defined by Ulpian, ib. ; exemplified,
332-3.
Space, or Extension, as absolutely bounded,
unthinkable, 73; as unlimited, inconceiva-
ble, because contradictory, ib. ; as an abso-
lute minimum, or as infinitely divided,
inconceivable, 74.
Special Logic, see Logic.
Special or Concrete Logic, see Logic.
Species, sff Genus.
Speculation as a means of knowledge, ««
Knowledge, Doctrine of the Acquisition
and Perfecting oL
Stattleii, 42; quoted on canons of syllo-
gism, 566.
Stepiianus, H., 85; his imitation of an epi-
gram of Phocylides, 280.
Stewart, Dugald, quoted on the liability of
notions to vagueness and ambiguity, 123-5;
■ refers to Hume and Campbell, ib. ; his un-
favorable strictures on the alleged modern,
origin of certain teehnicallogical language,
groundless, 146, 197, 418; quoted ou influ-
ence of association, 421-3, 430, 431.
Stoicheiology, or doctrine of Elements, .«««
Logic.
Stoics, viewed Logic as a science, 7 ; thei»
nomenclature of the parts of the Hypothetfe
ical Syllogism, 241; the excogitation of the
sophism Ign/ima Ratio attributed to, 33Q;
but this doubtful, 331.
Stbabo, 280.
Stp.igelius, 526.
SuABEZ, on the principle of Contradiction,
63,66; referred to on classification of the
categories, 141.
Subject, of a Judgment or Proposition,
what, 161; called term or txtretne, ib., u*
Judgments, Propositiou.
no
INDEX.
Subjective Logic, »ee Logic.
Subsidiaries or Aids of thinking, Doctrine
of, ut Logic.
Subordination of Concepts, ttt Concepts,
Relations of.
Sufficient Reason, or Reason and Conse-
quent, principle of, a fundamental law of
thought, 57 (frtit we 61); what and how ex-
pressed, 60; relations between Reason and
Consequent, 60-1; logical significance of,
61 ; discriminated from the principle of
Cause and Effect, ib. ; logiccU and metaphysi-
cal reason and consequent, ib. ; these both in-
cluded under the terms condition and condi-
tioned, ib.; this law should be excluded
from Logic, i6. ,• recognized by I'lato, 66;
by Aristotle, ib.; by both under the ambig-
uous term atria, aXrtoy (cause), ib. ; but the
principle of Knowledge discriminated by
Aristotle from the principle of Production,
66-7 ; comprehended by Cicero, and by the
schoolmen, under the formula nihil sine
tausa, 67 ; but under that discriminated, ib. ;
in modern times attention called to it by
Leibnitz, ib. ; but not adequately discrim-
inated by him, ib. ; controversy between
Leibnitz and Dr. Samuel Clarke on this
law, among other points, t6. ,- assumed by
Leibnitz as the foundation of Natural
Philosophy, ib. ; the form of the Hypothet-
ical Syllogism determined by, 239; how-
enounced by Wolf, 67; discussion regard-
ing the Leibnitian principle of, 63; law of,
regulates, in conjmnction with that of ex-
cluded middle, Hypothetico-disjunctivesyl-
logisnos, 204-5; only another expression of
Aristotle's law, that the whole is neceasarily
conceived as prior to the part, 253-4; au-
thors referred to on, 509; that can be de-
duced from law of Contradiction, ib. ; that
cannot be so deduced, ib., set Fundamental
Laws of Thought.
SuiDAS, 334.
SuumoN and Subeumption, best names for
the premises of a syllogism, 199; their em-
ployment vindicated, 199-200; not consti-
tuted by the mere order of enunciation,
218; what truly constitutes these, 219.
SuTEii, quoted on canon of Syllogism, 567.
Syllogism, original meaning of the term,
196; borrowed from Mathematics, ib. ; Eu-
genios, Ulemmida.«, and Zabarella quoted
on Import of, 197, 198, tt seq. ; general con-
ditions of, 197; the parts of which com-
po!<ed, and their denominations, 197-8;
these explicated, 198, et seq. ; Tremises, ma-
jor and minor, 190; Sumption, Subsump-
tion, Conclusion, best mimes for the three
propositions of, ifr. ; Lemma, Ilypolemma,
t6. ,- Assumption, 200; objections to the
denomiuations of the propositions of, in
ordinary nse, ib. ; the nse of Sumption and
Subsumption sanctioned by precedent, 201 ;
Divisions of, ib. et seq. ; first division of
Syllogisms, comprehending all the others,
into Extensive and Comprehensive, 201-2;
matter and form of, 202-3; proximate and
remote matter of, 202 ; the form affords the
next grand distinction of, 203; the form of,
twofold — Internal and External, ib.; I.
According to Internal or Essential Form,
Syllogisms are divided into four classes, as
regulated by the laws — 1^, Of Identity and
Contradiction, 2^, Of Excluded Middle, 2P,
Of Reason and Consequent, and, 4°, Of
Excluded Middle and of Reason .and Con-
sequent, viz., Categorical, Disjunctive, Hy-
I>othetical, and Uypothetico-di-juuctive, or
Dilemmatic, 205-6 (but see 598-600, and Infer-
ence); these four classes comprised in two
genera. Simple and Conditional, 206, see
Categorical, Hypothetical, Disjunctive and
Hypothetico-disjuuctive Syllogism; Cate-
gorical Syllogism, the one class under the
genus Simple Syllogism, 206; its general
I nature, 206-7; may proceed in the quantity
j of Extension, and in that of Comprehen-
sion, 207-8; examples of tMb Extensive, and
of the Intensive or Comprehensive Cate-
gorical Syllogism, 203; these reasonings or
syllogisms explicitly compared and con-
trasted, 209 et seq. ; logicians looking only
to the reasoning in Extension have given
narrow and erroneous definitions of the
Major, Middle, and 3Iinor terms, 209-10;
Aristotle's definition of these will apply to
both quantities, 210-11, see aUo 154-5. ste
Terms of Syllogism ; most convenient node
of stating a syllogism in an abstract form
by the letters S, V, M, 211-12 (hut see 674.
676, 678); divided into special classes accord-
ing to the application of the laws of Iden-
tity and Contradiction, under the relation
of whole and part, 212 tt seq ; this rela-
tion may be regarded in two points of
view, and thus affords two classes of Rea-
sonings, viz.. Deductive and Inductive,
212-13; I. I>eductive Categorical Syllogism,
character of the process in, 213 tt seq. ; its
canons, in Intension and in Extension,
213-14; connection of the propositions and
terms of, illustrated by sensible symbols,
214-15; proximate rules of, 1 Extensive —
Three Rules, 215; tirst rule of, illustrated,
216-17; second rule of, illustrated. 217-19;
misconception in regard to definition of
Sumption in second rule obviated, 218-19;
third rule, 219-20; 2. Intensive, three rules.
222 tt seq ; first rule illustrated, 223; second
rule illustrated. 223-4; grounds of the rules
regarding Sumption and Sul>sumption in
Extensive and Comprehensive Syllogisms.
INDEX,
711
224; third rule illustrated, 224-5; II. In-
ductive Categorical Syllogism, what, 225;
views of logicians regarding the nature of
this reasoning erroneous, 225 et seq., see In-
duction ; canons of the Deductive and Induc-
tive Syllogisms equally formal, 227; these
reasonings illustrated, 227-8; objection obvi-
ated, 228; formula) for Inductive Syllogisms
in Compreljension and Extension, 228-9;
Whately and others erroneously make the
inductive syllogism deductive, 229; doctrine
of the older logicians different, and correct
as far as it goes, 229-30 ; though the Cate-
gorical Syllogism is specially regulated by
the laws of Identity and Contradiction,
still the other logical laws also operative in,
261; Divisions of according — II. To E.xter-
nal Form, 257-320 ; A. Complex, — Epi-
cheirema, and Sorites, 257-74 ; relation of
syllogisms to each other, 258; classes and
designations of related syllogisms, ib. ;
Monosyllogism, what, i6.; Polysyllogism,
what, ib.; this Analytic and Synthetic, i6. ;
Prosyllogism, ib. ; Episyllogism, ib , see
Epicheirema, Sorites; probable reason why
logicians, in the case of simple syllogisms,
overlooked the reasoning of Comprehen-
sion, 270-71; divisions of, according to
External Form, B. Defective, — Enthy-
meme, 275-81, iee Euthymcme; C. Regular
and Irregular, 281-320, .<ee Figure, Mood,
Reduction of Syllogisms; irregular by re-
lation, 1°, To the transposed order of its
Propositions; 2°, Of its Terms; 3^ Of both
its Propositions and Terms, 281-2; doctrine
of logicians regarding the regularity and
irregularity of, in respect of the order of
its propositions, 281; this one-sided and
erroneous, 282; in respect of its Terms, a
syllogism is regular or irregular, according
to the place which the Middle Term holds
in the premises, ib. ; regular and irregular
order of, in Comprehension and Extension,
282; the relative position of the Middle
Term in a syllogism constitutes its Figure,
i6. ; the Four Figures of, ib. ; mnemonic
verses for Figures, ib.,see Figure of Syllo-
gism; regularity and irregularitj^f, expli-
cated, 283 et seq. ; irregularity in external
form of, arising from transposition of the
I'ropositions, 283-5; can be perspicuously
expressed by any of the five irregular con-
secutions of its propositions, 283-4; true
doctrine of consecution of syllogism, which
is either Synthetic, the premises being
placed first, the conclusion last, or Ana-
lytic, the conclusion preceding, the prem-
ises following, 284-5; second ground of
regularity and irregularity of, — the natu-
ral and transpo.sed order of the Syllogistic
Terms, 285 et seq., set Figure of Syllogism;
all the varieties of, divided into classes, ac-
cording to their Validity, viz., into Correct
or True, and Incorrect or False, 321; the
meaning of these terms as applied to syllo-
gisms determined, 322; incorrect, divided
into Paralogisms and Sophisms, 321-3 ; this
distinction not of directly logical imi;oit,
323; but not altogether without logical
value, ib.; incorrect, vicious, either in re-
spect of their form, or of their matter, or
in respect of both form atid matter, 322-3;
syllogisms incorrect in respect of their mat-
ter lie beyond the jurisdiction of Logic,
323; syllogisms formally incorrect, to bo
judged by an application of the rules of
syllogism, ib., .^ee Fallacies; how distin-
guislied from Probation, 361; on the mu-
tual relations of the terms of, in quantity
and quality, through the ai)plicatJon of the
doctrine of a quantified predicate. 536-9;
general canon of, 53i5; the" three possible
relations of terms, — 1. Toto-total Coinclu-
sion; 2. Toto-total Coijxclusion ; 3. Incom-
plete Coinclusion, involving Incomplete
Cocxclusion, ib. ; the fiist is the best, the
second the worst, the third intermediate,
ib. ; the whole order of best and worst
quantification throughout the two qualities,
537; application of this doctrine in special
cases of the general canon of, in the 12 af-
firmative and 24 ne;;ative moods. 537-9 ;
Canons of, general historical notices re-
garding, 559-79; quotations from various
logicians on, 559-75; Derodon referred to
in, 559-60; Kapin, 560; Leibnitz, 560-61;
Reusch, 561; Crusius, 561-3; iiutchoson,
663-4; Savonarola, 564; Alex. G. Baum-
garten, 564-5; Reimarus, 565; Waldin,
565-6; Stattler, 566; Sauter, j6. ; Suter, 567;
Seguy, 567; Hoflbauer. 567-8; Kant, 568-9;
Christian Weiss, 569; Fries. 570-2; Kiese-
wetter, 572; Larroque, 572-4; Galluppi, 574;
Buffler, ib. ; Vietoi in, 575; references to au-
thors on fundamental laws of, 575-6; enun-
ciations of, 576-8; Dictum de omni et nullo,
criticized, 578; general Ipws of, in verse,
578-9 ; criticism by the author of the spe-
cial laws of, 579-83; the author's supreme
canons of, 583-4; doctrine of. attacked, as
involving a petitio principii, 621; how this
objection is to be met, 621. 0-3 ; this objec-
tion made by Stewart and refuted by Gal-
luppi, 623; its enouncement— Analytic and
Synthetic, 621-2; these met hods of enounce-
ment compared, 622, 623; Unflgured and
Figured, 626; difference of Figure of, of no
account, 626-7.
Symbolical and Intuitive Knowledge, m«
Concepts, Quality of.
Synthesis, 338, see Method.
712
INDEX..
Tacitits, quoted, 427.
Tartauetus, I'etrug, commentator on His-
imiius, 1.S7, MB.
Tk-nnkmanx, 142.
'i LUMftofa riopofition, sfe Proposition.
■| liij.MS of Syllogism, Major, Minor, and
Jlifklle, what, 207; borrowed from Matlie-
iiiatic!--, 210; their synonyms, j6.; in Exten-
sion the predicate of the conclusion the
greatest whole, and, therefore, the major
term, the subject the smallest part, and,
therefore, the mir.or term. 20"; incompre-
hension, the subject of Die conciusiou is
the greatest whole, and, therefore, the ma-
j6r term, the predicate the smallest part,
and, therefore, the minor terra, ib. ; narrow
and erroneous dclinitions by logicians of,
209-10: Aristotle's definition of, 210; his
definition of the middle term as middle
by i)osilion not applicable to the mode in
wliich subsequent logicians enounce the
syllogism, ih.; but applicable to the rea-
soniag in Compreher.sion, 211; poss-ible to
state a reasoning in E.\ttMision in which the
major term shall stand first, the middle
second, and the minor lat-t, i6. ,• what is
projKjrly to be regarded as a term of syllo-
gism, 216.
Testimoxv, what, 457; explicated, 458 ft aeq ;
its picpcr object, 45S-9; the object of, called
tl'.c Fact, 451); the validity of. called Hix-
torical Cr-rlibilittj, ib. ; cither immediate or
mediate, ib. ; an immediate witness styled
au ei/e-icitne.\x, ib ; n mediate an enr-witne^^,
ib. ; the f^iiamiiifr, wl;a:, ib. ; testimony may
be I'artial, Comp'etc. (onsisfent, Contrn-
dictorv, ih.: divi.-ion of the subject: — I.
(.'redibilily of Testimony in general, ib. et
.*<■</ ; 1'^, The olject of the testimony — its
absolute possibility, 400; physical and tnet-
aphrsiCHl possibility, 460-61: its relative
l)<)s.>-ibilit.y, 451 ; '2P. The subject of, or per-
K)iial trustworthiness of tJie witness, ib.;
this consists of two elements, a. Honesty or
veracity, 461-2; the presumption of the
honesty of a witness enhanced by certain
circumstances, 462; b. Compcttnicy of a
witness, ib. ; circumstances by which the
pivsumpfion of competency is enhanced,
(6. ,■ the credibility of Testimony not invali-
dated because the fhct testified is one out
of the ordinary course of experience, 463;
summary regarding the credibility of testi-
mony in general. 4(i3-i; II. Testimony in
special, as immediate and m-idiate, 464 et
Sfq. ; 1^, Immediate, ib. ; conditions of its
credibility, il>. ; whether all these condi-
tions are fulfilled in the case of any imme-
<liate testimony, cannot be directly ascer-
tained, 461-5; when testimony attains the
taigliest degree of probability, 465; iiegativ"
and, positive discrepancy^ 46%ff; 2°, Sledi-
ate, 4GG ft.seq. ; mediate wJine.-ises are eitiier
proximate or remote, and either indepen-
dent or dependent, 468-7; liumor, Tiadi-
tion, ib.; Recorded Testimony, 468 ft seq. ;
Criticism and luterpretutiou, what. 468-9;
these explicated, ^)9 n seg. ; the examina-
tion of a testimony twofold — of ita Au-
thenticity and Integrity, and of its Meaning,
ib.; the former the problem of Criticism
(Criticn), the latter of Interpretation or
exposition (H-rjnemutica, Eregetica), 470;
I. Criticism considered in detail. 470-74; its
problems, 470; Universal and Special Criti-
cism, ib. ; Universal Criticism alone within
the sphere of Logic, ib ; this divided into
Higlier and Lower Criticism, or the Criti-
cism of Authenticity and the Criticism of
Integrity, ib.; (1) Criticism of Autlienticity,
470-71; a. Internal Grounds, these of them-
selves not suiBcieut to establish the authen-
ticity of a writing, 471; but omnipotent to
disprove an alleged authenticity, ib.; b.
External Grounds, ib. ; (2) Criticism of In-
tegrity, 472-4; emendation of the text of
two kinds — viz.. Historical and Conjectu-
ral, 472; historical, of two kinds. External
and Internal, 473; Conjectural, t6.,- II. In-
terpretation, 474-5: Generjil and Special,
474; sources of interpretation, 475.
Text-Book, its use in a systematic course of
Lectured. 2.
TuEMiSTiL'S, referred to on genus of Logic,
7, 479.
Thegphkastcs, referred to on use of the
term rates;oTicnl, K5, 172: his nomenclature
of the parts of the Hypothetical Syllogism,
241; quoted on hearing, 484; made two
moods of Daiapti, 686; this opinion adopted
by Porphyry, ib. ; and by Boethius, ib. ; but
opposed by the author, i&.
Tbeouems, what, 18H.
Third Figure, ser Figure.
TuoMAfsius, Jacobus, holds that simple ap-
prebensiou is impossible without judgment,
84.
Thought, the Products, of, ate Concepts,
Judgm?iit8, Keaiiouiug.
Thought, what, 9 ft seq. ; in its wider mean-
ing, equivalent to every cognitive act, or
even to every conscious mental modifica-
tion,9; in its narrower meaning as thought
proper, denotes the acts of the Understand-
ing proper, 9-10; in the hitter sense, the
object-matter of Logic, 9: Matter and Form
of, disthiguished, 11; phenomena of for-
mal, of two kinds, contingent and neces-
sary. 17; necessary form of, implies four
conditions, — (1) Determined by the nature
of the thinking subject itself, (2) Original,
(8> Universal, (4) A Law, 17, 18; its Mii^^
INDEX.
713
form, iiiul matter disciiminatccl, £3; as the
■object respectively of Psychology and of
Logic, »Va ,- a mcdinte and complex cogni-
tion, 54-5; the various terms by wliich the
modes 'of thought, or cogitable existence,
are designated, 55-G; what is involved in
thinking an object, 55; the attribution im-
plied in, regulated by laws, 56, see Funda-
mental Laws of Thought; distinction of
Positive and Negative, 73; its products are
of three kinds, — Concepts, Judgmer.ts, and
Heasouings, 83 ft alibi; these arc all prod-
ucts of comparison and all moditications of
Judgment, S3-4, see Concepts, Judgments,
Reasonings; its formal or logical perfec-
tion consists of three virtues, — Clearness,
Distinctness, and Harmony, 335, 340.
TiMPLER. 37, 13S; referred to on whole and
part, 143, 140. 333, 339.
TiTiDS, Gottlieb Gerhard, referred to on ap-
plication of quantification of predicate to
the Hypothetical Proposition, 512; his doc-
trine of Conversion proceeds on the doc-
trine of a quantitied predicate, 627; quoted
on quantification of predicate, 556; his
doctrine of Hypothetical Syllogism as pro-
ceeding on the application of the principle
of a quantified predicate, 603; his doctrine
of Disjunctive Syllogism, ib.; held both
forms merely to be the matter of regular
syllogism, ib. ; his doctrine of the Figure
and Mood of Syllogism, 652-8.
TiTTKL, 435.
Topic, employed by Aristotle to denote a
particular part of Logic, 6.
ToussAiNT, 435.
Transuexdent and Transcendental, their
original application, and use by Kant, 140.
TuENDELENnuRO, F. A., referred to on the
title Orifaiion for the logical treatises of
Aristotle, 24; referred to for the doctrines
of tlie Platonists and Stoics on the Catego-
ries, 142, 188, 260. 333.
Troxler. 33, 249, 333.
Truth, its division into Logical and Metg-
physical, criticized, 76; what, ib. ; logical
discriminated from absolute, 322, see Truth
and Error, Doctrine of.
Truth and Error, Doctrine of, 376-90; Truth
and Certainty, what, 377; Truth is defined
the correspondence or agreement of a cog-
nition with its object. 377, 378; this defini-
tion due to tlie schoolmen, 378; Aquinas
quoted to this eflect, ib ; philosophers
agreed as to the definition of truth, ib ;
questions in debate regarding, — whether
truth be attaliial)Ic, and wlwther we possess
any criterion by AVincli we can be assured
of its attainmenf, Jh ; lor niiin only two
kinds of, —Formal and Heal, .37'J; I. For-
mal Truth, the harm<>ny of Thouglit with
90
the form of Thought, ib. ; Formal Truth of
two kinds. — Logical and JIathematical,
379-80; II. Keal Truth,— the harmony be-
tween a thought and its matter, 3S0; Ileal
and Fcrmal Sciences, 380-81 ; How can wo
know that tliere is a correspondence be-
tween our thought and its object? 381; fub-
divis^ions of Real Truth, — Jletaphysic.Tl,
Psychological, Physical, 381-2; various a] -
plications of the term truth, SSI; tlie cri;e-
rion of. — the necessity determined by the
laws wliich govern our faculties of knowl-
edge, 377-82; Certainty, the consciousness
of this necessity, 382; truth considered in
relation to the degree and kind of certainty
is distinguished as Knowledge, Belief, and
Opinion, 377-83; Knowledge and Belief, ~
their dilTurence, 383; that the certainty of
all knowledge is ultimately resolvable into
a certainty of belief maintained by Luther,
ib.; by Aristotle, 383-4; by the Platoni.sts,
384; by David Hume, ib. ; the manifestation
of Belief involves knowledge, 3S5; Intui-
tion, what, ib.; the question as to the rela-
tion of belief and knowledge properly met-
aphysical, »6. ; Pure and Empirical Truth,
distinguished, 385-6; Error, its character
and sources, 3S7; this explicated, ib. et seq. ;
as the opposite of truth, consists in a want
of agreement between a thought and its
object, 387; distinguished as Slaterial. 38-:
as Formal, ih.; when closely scrutinized is
found to arise from the want of adequate
activity of the cognitive faculties, ib.; dis-
criminated from Ignorance, 389; from Illu-
sion, lb., ste Error, Causes of.
TSCHIRXHAUSliN. 25.
TwEPTEN. 237, 377, 387; quoted on the nature
of Error. 387-9; quoted on ignorance, Illu-
sion, €tc., 389-90.
Ulpia>', his doctrine of the Enthymeme, 279;
his definition of the Sorites, 3.32.
ULniCH, 184, 2S9; quoted on quantitication of
predicate, 559.
Ultua-total Quantification of SliddleTerm,
Lambert's doctrine of, 384-0; this doctrine
criticized, 6S4-5; author's doctrine of,
586-8.
Universal Propositions, 171. see Judgments.
"TcTTepoy TrpArtpov, see Probation.
Vali-a, Laurentius, 142, 261; first to use the
term Sorites m its present application. 269;
quoted on Conversion. 527; his doctrine of
the Second and Third Figures, €29-30.
Valerius Maximus (?) quoted, 4-4.
VALLiU8,Paulus, quoted on Conversion, 628,
553
VA KILL AS, 485.
Versok, liis doctrine of IiKlucfion, 596.
714
INDEX.
Victoria, 338, 344; quoted on canons of
Sj'Ilogism, 575.
Vi^jTORixus, liis doctrine of Enthymeme, 279.
VlTlDM Subreptionis, what, 427.
ViVES, Liulovicus, 198; his opinion regard-
ing silent meditation as a means of intel-
lectual improvement combated by Scal-
iger,4Sl; quoted on importance of teaching
as a mean of .self-improvement. 483.
VOET, or Voetius, Gisbert, liis conduct cited
as an instance of the influence of passion
on opinion, 406.
Vossius, Gerard John, referred to on genus
of Logic, 7; referred to for scholastic theo-
ries of the object-matter of Logic, 20, 37.
Waitz, quoted regarding \oyiK)i avopia, 4,
85. 160, 186, 193, 240.
•VValcii, 261.
Waldin, quoted on canons of Syllogism,
565-6.
Wallis, Dr. John, his Institutio Logictr, 21;
referred to on names of propositions in
Conversion, 185; referred to on character
of Hvpotlietico-Disjunctive Syllogism, 249;
his English version of the Latin mnemon-
ics for the four kinds of propositions, 287.
AValz, 333.
Watt8, Dr. Isaac, 25; his Logic, 50.
Weoelin, 514, 547.
Weise, Christian, e\pployed (before Euler)
circular diagrams as logical notation, ISO.
Weiss, Christian, 1C9; quoted on canons of
Syllogism. 569.
Wkrenkelsius, his De Lngomarhiis Erudilo-
Tinn referred to, 433.
WiiATELY, Dr.. his definition of Logicquoted
and criticized, 7-9; general character of
his Elements of I^gir, 21 ; his view of the
object-matter and domain of Logic, stated
and criticized, 21-3; propo.«es to Logic
diflereiit and contradictory object-matter,
22 ft se(/. ; the ojieration of Ueasoning not
tlie object-matter of Logic, us affirmed by,
ib.; erroneously and contradictorily makes
Language the object-matter of Logic, 22-3;
the true nature of Logic more correctly un-
derstood by the scholastic logicians than by,
23; his EUmnUs nf Logic, 50; omits the doc-
trine of Concepts from his Elements of
Logic, 84; abusively employs the terms Ex-
tension and Comprehension as convertible,
85, 184; follows Aldrich in his abusive em-
ployment of the phrase propofitio erposiln,
185-6; his abusive employmentof the terms
hypothetical and conditional, 167; quoted ou
the modality of propositions, 182; his doc-
trine criticized, ib. ; his reduction of the
rules of Categorical Syllogism to six, 215,
454.
Wholk aad Fart, what, 143; whole per se,
and whole per aecidens, ib. ; whole per te
dividud into, 1°, Logical or Potential, 2°,
Metaphy-icrJ or Actual, 3^, Physical, 4^,
Mathematical, 5°, Collective, 143-4; the
terms subjfrt and subjective as applied to the
Logical Whole and Parts 144; the term.
potential as applied to denote the Logical
Whole, 145; Lord Monboddo quoted on
potential, libS; Stewarfs strictures on the
pai=sage from Monboddo rebutted, 146;
Monboddo wrong in ascribing the author-
ship and application of the term potential
to Eugenius, 146; both term and applica-
tion to be found, with few exceptions, in
all the older systems of Logic, ib. ; Burg-
ersdyk quoted as an example, i6. ;the dif-
ference of the Potential and Actual Whole
noticed by Aristotle, ib. ; all reasoning
under the relation of, 191,212; this relation
may be regarded in two points of view, and
thus affords two classes of Reasonings, — '
Deductive and Inductive, 212-13; diflSculty
in connection with Hypothetical Syllo-
gisms in regard to the doctrine that all rea-
soning is either from the whole to part or
from the parts to the whole, — considered
and obviated, 262 tt seq.; Antecedent and
Consequent in Hypotheticals equal to Con-
dition and Conditioned, 253; hence the
reason or condition must contain the con-
sequent, ift. ,• the law of Reason and Con-
sequent only another cxpres.«ion of Aris-
totle's law, That the whole is necessarily
conceived as prior to the part, 253-4; Aris-
totle's law criticized, 254; Whole and Parts
respectively may be viewed in thought
either as the conditioning or as the condi-
tioned, 254; application of this doctrine to
the solution of the difficulty previously
stated, 255.
Wilson, his English metrical version of the
Latin mnemonics for the four kinds of
Propositions, 287.
AVoLF, Christian, misapplied the terms Logica
docens and Logica vtens, 42 ; his division of
Logic into Theoretical and I'ractical, ib . ;
used the phrase excliisio medii inttr eontradic-
toria, 65; called the principle of Identity
principivm certiliidinis, 66; did not sufB-
ciently discriminate the principles of Ident-
ity and Contradiction, ib. ; his formula for
the law of Sufficient Reason, 67; blamed the
schoolmen for not distinguishing reason
{ratio) and cause {causa), ib.; attempted to
demonstrate the law of Sufficient Reason
by that of Contradiction, 68 ; quoted on
Intuitive and Symbolical Knowledge, 129-
31,178,227; made the inductive syllogism
deductive, 229, 240, 24S, 261; his reduction
of Baroco, 341, 343, 451, 456.
WoLFiA>'S, some, distinguished judgments as
INDEX.
715—731
Limitative, 1T9; followed by Kant, 178; the
distinction groundless, 179-
Words, n'e Language.
"Wyttenbach, Daniel, 5; his Logic recom-
mended, 50, 332; referred to on Analysis
and Synthesis, 435.
ZAit.\iiELLA, Jacobus, referred to on genus
of Logic, 7; referred to for scholastic theo-
ries of the object-matter of Logic, 20 ;
quoted on import of the term crv\Koytafi6s,
197, 230,296; held Cesare and Camestres to
be the same syllogism, 310, sef aUo 296, 336,
838, 451.
Zedlke, 456.
Zeko, the Stoic, said by Laertius to have
purchased the knowledge of seven fpeciei*
of the argument Koyos bepi^uy for two
hundred raiu%, 331.
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