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Full text of "New essays concerning human understanding"

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NEW ESSAYS 



CONCERNING 



HUMAN UNDERSTANDING 



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NEW ESSAYS 



CONCERNING 



HUMAN UNDERSTANDING 

BY 

GOTTFRIED WILHELM LEIBNITZ 

TOGETHER WITH 

AN APPENDIX 

CONSISTING OF SOME OF HIS SHORTER PIECES 

/ ^Sd I 

TRANSLATED FROM THE ORIGINAL LATIN, FRENCH 
AND GERMAN, WITH NOTES 



ALFRED GIDEON LANGLEY 
A.M. (Brown) 



THE MACMILLAN COMPANY 

LONDON: MACMILLAN & CO., Ltd. 
1896 

All rights reserved 



Copyright, 1S96, 
By the MACMILLAN COMPANY. 



NortoooO ^rfss 

J. S. Cushing & Co. - Berwick & Smith 
Norwood Mass. U.S.A. 



3 



STo mg IKotfjcr anb Sister 

SOMETIME GONE WHERE WE SHALL KNOW AS WE ARE KNOWN 

^ntJ to mg Jatf)£r 

STILL WHERE WE SEE AS IN A MIRROR OBSCURELY 

IN DEEPEST LOVE AND GRATITUDE 

I DEDICATE THIS BOOK 



CONTENTS 



Translator's Preface xi 

Gerhardt's Introduction to his edition of Leibnitz's Nouveaux 

Essais 3 

LEIBNITZ'S CRITIQUE OF LOCKE 

On Locke's Essay on Human Understanding, 1G96 .... 13 
Specimen of Thoughts upon the First Boole of the Essay on Human 

Understanding, 1698 20 

Specimen of Thoughts upon the Second Book, 1698 .... 23 
On Coste's Translation of Locke's Essay concerning Human Under- 
standing ; from the " Monatliche Auszug," September, 1700, 

pp. 611-636 26 

Addition thereto. " Monatliche Auszug," 1701, pp. 73-75 . . 37 

New Essays on The Understanding, by the Author of the 
System of Pre-established Harmony 

Preface 41 

Bnnl- I. — ■ Innate Ideas 

CIIAPTRR 

I. Are there innate principles in the mind of man ? . . .64 
II. No innate practical principles ....... 85 

III. Otlier considerations toucliing innate principles, both spec- 
ulative and practical 100 

lindk I J. — Ii/cas. 

the way 



I. Which treats of ideas in general, and examines by 
whether the mind of man <ilways thinks , 
II. Simple ideas 

III. Of ideas which come to us by one sense only . 

IV. Of solidity 

V. Of simple ideas whicli come by different senses 

VI. Of simple ideas wliich come by reflection 

vii 



109 
120 
121 
122 
129 
130 



CONTKNTS 



riiAi-ui: PACE 

Vll. Of ideas which come by sensation and reflection 130 

VIII. Other considerations upon simple ideas .... 130 

IX. Of perception 135 

X. Of retention 142 

XI. Of discernment, or the faculty of distinguishing ideas . 143 

XII. Of complex ideas 147 

XIII. Of simple modes, and first of those of space . . . 149 

XIV. Of duration and its simi)le modes 155 

XV. Of duration and expansion considered together . 158 

XVI. Of number IGO 

XVII. Of infinity 161 

XVIII. Of other simple modes 1G4 

XIX. Of the modes of thmking 164 

XX. Of modes of pleasure and pain 167 

XXI. Of power and freedom 174 

XXII. Of mixed modes 221 

XXIII. Of our complex ideas of substances 225 

XXIV. Of collective ideas of substances 235 

XXV. Of relation 235 

XXVI. Of cause and effect and some other relations . . . 237 

XXVII. What identity or diversity is 238 

XXVIII. Of some other relations, and especially of moral relations 258 

XXIX. Of clear and obscure, distinct and confused ideas . . 265 

XXX. Of real and fantastical ideas 275 

XXXI. Of adequate and inadequate ideas 278 

XXXII. Of true and false ideas 281 

XXXIII. Of the association of ideas . . . . . . 281 

Book III. — Words. 



I. Of words or language in general 285 

II. Of the signification of words 291 

III. Of general terms 307 

IV. Of the names of simple ideas 318 

V. Of the names of mixed modes and relations . . . 325 

VI. Of the names of substances 330 

\ai. Of particles 364 

VIII. Of abstract and concrete terms 368 

IX. Of the imperfections of words 369 

X. Of the abuse of words 376 

XI. Of the remedies which may be applied to the imperfec- 
tions and abuses just spoken of 390 



CONTENTS 



Book I V. — Of Knowledge 

CHAPTER 

I. Of knowledge in general 

II. Of the degrees of our knowledge 

III. Of the extent of human knowledge 

IV. Of the reality of our knowledge . 
V. Of truth in general 

VI. Of universal propositions, their truth and certitude 

VII. Of propositions called maxims or axioms . 

VIII. Of trifling propositions 

IX. Of our knowledge of our existence 

X. Of our knowledge of the existence of God . 

XL Of our knowledge of the existence of other things 

XII. Of the improvement of our knowledge 

XIII. Other considerations concerning our knowledge 

XIV. Of judgment 

XV. Of probability 

XVI. Of the degrees of assent 

XVII. Of reason . . . . . . . ^ . 

XVIII. Of faith and reason and their distinct limits 

XIX. Of enthusiasm 

XX. Of error 

XXI. Of the division of the sciences .... 



PAGE 

397 
404 
423 
444 
449 
452 
462 
490 
497 

44e*»^°i 

511 '■ — 

517 

528 

528 

529 

532 

555 »— 

583 . 

596 

607 

621 



APPENDIX 



I. 

II. 
III. 

IV. 



V. 



VI. 
VII. 



Leibnitz to Jacob Thomasius. April 20-30, 1669 . . .631 

Fragment, (c. 1671) 651 

Demonstration against atoms taken from the contact of 
atoms. (October, 1690) 

Essay on Dynamics on the laws of motion, in which it is 
shown that not the same quantity of motion is preserved, 
but the same absolute force, or rather the same quantity 
of moving action (Z'aciJow moince). (c. 1691) 

Essay on Dynamics in defence of the wonderful laws of 
natui'e in respect to the forces of bodies, disclosing their 
mutual actions and referring them to their causes, 
Part I. 1695 

lb. Part II. 1695 

On the radical origin of things. 1097 .... 

Appendix to a letter to Honoratus Fabri. 1702 . 



652 



657 



670 
684 
692 



X CONTENTS 

PAGE 

\'lll. Li'lliT of lA'iliiiit/. to P.jisiiiii^c dc Bcauvixl, editor of the 
" Ilistoiro des Ouvrages des Savants," printed in that 

journal, July, 1098, pp. ;W0s(7 706 

IX. Fragment of a letter to an unkilown person. 1707 712 

X. That the most perfect Being exists 714 

XI. What is idea 716 

XII. On the method of distinguishing real from imaginary phe- 
nomena 717 

AnnniONs and CoiMiECTiONS . . . . . . . . 721 

Index A. To the Critique of Locke 777 

Index B. To the Appendix 823 

Index C. To the Notes, Additions, and Corrections . . . 831 



TRANSLATOR'S PREFACE 

The work herewith given to the public consists of a transla- 
tion of the entire fifth volume of Gerhardt's Die pliilosophischen 
Schriften von G. W. Leibniz, sub-entitled "Leibniz und Locke," 
consisting of an Introduction by Gerhardt, several short pieces 
on Locke's Essay and the Neio Essays on Human Under- 
standing ; and of an Appendix contaiuing a translation of 
other short pieces of Leibnitz bearing on the subjects dis- 
cussed in the Neio Essays or referred to therein. The Intro- 
duction on The Philosophy of Leibnitz by the translator 
suggested and urged by Professors Palmer and Royce of Har- 
vard University, and for some time contemplated, is deferred, 
and reserved, if at all, for another time and occasion, owing 
to the size of the present volume, as well as for other good 
and sufficient reasons which it is not necessary here to 
mention. 

Tlie translation of Leibnitz's JSlouveaux Essais sicr VEntende- 
\^ ment Hmnain was first suggested by the following sentence 
:s^ of the late Professor George S. Morris, of the University of 
I Michigan, in a note to his Philosophy and Christianity, page 
J^ 292: "It suggests no favorable comment on the philosophic 
J interest of the countrymen of Locke that the above-mentioned 
reply of Leibnitz to Locke has never (so far as I can ascertain) 
been translated into English." Four instalments, consisting 
of Book I. and Book II., chapters 1-11 inclasive, were pub- 
lished in as many numbers of the "Journal of Speculative 
Philosophy."^ Professor Morris very kindly sent me a care- 
ful criticism of about one-third of the first instalment, with 
valuable suggestions regarding the further wbrk of transla- 
tion. His corrections and suggestions received careful con- 

1 Vol. 19, No. 3, July, 1885; Vol. 21, No. 3, July, 1887; Vol. 21, No. 4, Octo- 
ber, 1887 ; Vol. 22, No. 2, April, 1888. 

xi 



TRANSLATOR'S PREFACE 



sicK-ratioii ami wore embodied in subsequent revisions of the 
translation in pre})aring it for the present issue. 

The portion of the New Essays thus published being 
favorably received by professors and students of philosophy 
in this country and in Europe, and being encouraged to go on 
and translate the entire piece, the work begun in 1885 was 
continued in leisure hours until in June, 1891, the translation 
was completed. Revision, annotation, and the labor of get- 
ting it through the press have occupied the greater part of my 
free time since then. The annotation, which was not a part 
of the original plan, but which was found to be desirable, if 
not even necessary, as the sheets began to appear in type, has 
been the chief cause of the delay in the appearance of the 
book, the labor involved therein proving far greater and una- 
voidably more protracted than was expected, the annotation 
also, as is frequent in such cases, growing with the progress 
of the book. 

The text-basis of the translation is that of C. I. Gerhardt, 
in his Die philosophiscJien Schriften vo7i G. W. Leibniz, 7 vols., 
Berlin, 1875-1890, except for the Dynamical Pieces in the 
Appendix, Xos. IV., V., the text-basis of which is C. I. Ger- 
hardt's Leihnizens mathematisclie Schriften, Berlin and Halle, 
1849-1863, and Appendix ISTo. VII., for which both these 
editions are used; for Appendix No. IX., the text is that 
given by Guhrauer, G. W. Freiherr v. Leibnitz. Eine BiograpMe, 
Breslau, 1846. The other editions used in the comparison of 
the text and the preparation of the notes are: J. E. Erd- 
mann, Leibnitii Opera Philosopliica, Berlin, 1839-1840; M. A. 
Jacques, (Euvres de Leibniz, Paris, 1842; P. Janet, (Euvres 
Philosophiqiies de Leibniz, Paris, 1866; Dutens, Leibnitii Opera 
Omnia, Geneva, 1768; Eoucher de Careil, Lettres et Opiiscides 
inedits de Leibniz, Paris, 1854, Nouvelles Lettres et Opuscules 
de Leibniz inklits, Paris, 1857, and (Euvres de Leibniz, Paris, 
1859 sq., 2d ed., Paris, 1867 sq. E. E. Raspe, (Euvres Philoso- 
phiqiies de feu Mr. Leibnitz, Amsterdam and Leipzig, 1765, was 
received too late to be of service, but as his text is the original 
printed text of the Neio Essays, and has been used by all sub- 
sequent editors, it is not probable that any important variation 
of reading has been overlooked; and Raspe's text has no notes. 
Besides these editions of Leibnitz's AVorks, the German trans- 



TRANSLATOTl'S PREFACE 



lations of the Theodicee and of the smaller philosophically 
important works entitled Die kleineren philosophisch loichtigeren 
Schriften by J. H. von Kirchmann, in his Pliilosophische 
Bibliothek, Berlin, 1879, and the English translation of his 
important philosophical opuscules by Professor George M. 
Duncan of Yale University, entitled The Philosophical Works 
of Leibnitz, New Haven, 1890, have been consulted. From 
the last-named work, so as to include in one book all of Leib- 
nitz's discussions of Locke, it was at first intended to re})rint 
in the Appendix all the pieces bearing upon the subject dis- 
cussed in the Neiv Essays, or espesially referred to therein. 
It finally seemed best to both Professor Duncan and myself 
to change the plan and translate new material, rather than 
duplicate that already translated, so that with the exception 
of Appendix No. VI., Professor Duncan's translation of which 
was either forgotten or unnoticed till after mine was in type, 
nothing appears in both books save such portions of the Neio 
Essays as he has included, and the piece entitled On Locke's 
Essay on Human Understanding, 169G. This statement Avill 
explain the references in certain notes, for example, page 101, 
note 1, page 154, note 1 (cf. infra, pages 737 and 749 respec- 
tively), to certain pieces of Leibnitz in the Appendix, which 
references are corrected in the Additions and Corrections by 
being changed to the proper pages of Professor Duncan's 
book. 

Of great value in the revision of the translation, and of the 
greatest service in the preparation of the notes, has been the 
German translation of the Nouveaux Essais, with notes, by 
Professor Carl Schaarschmidt of the University of Bonn. 
His material has been fi'eely used, either by direct translation 
and quotation, or in substance, in the notes of the present edi- 
tion, though always, so far as possible, only after verification 
and further independent study. His notes, I regret to say, 
contain many numerical errors, occasioned presumably by in- 
sufficient care and accuracy in proof-reading; otherwise they 
are, for the most part, accurate. The fact that Professor 
Schaarschmidt's book was not received till after a portion of 
mine Avas in type accounts in part for the appearance of so 
much of his note-material in the Additions and Corrections, 
rather than in its proper place in the foot-notes to the text. 



TRANSLATOR'S PREFACE 



Trofessor A. C. Frazer's splciulid edition of Locke\'i Essay, 
Oxford, 1804, did not ap})ear until after most of the New 
Essays were in type; and P. Coste, Essai i)1iiloso2)1iique. con- 
cernant V Entendement liumain — j?a?' M. Locke, Amsterdam, 
1742, 1 vol., 4to, 1774, 4 vols., 12mo, could not be obtained 
until all tlie New Essays and most of the Appendix were in 
type. Both of these works, therefore, could be used only in 
the supplementary notes in the Additions and Corrections. 

AVitli regard to the text itself, particularly of the Neic Essays, 
a few words may not be out of place. The variations ar(^ slight 
and chiefly verbal, and scarcely ever essentially modify the 
thought. They are ultimately due either to the manuscript of 
Leibnitz — which Erdmann (Preface, p. xxii) says is "written 
in such small characters often, and so full of corrections, that 
it is very diilicult to read it" ("tam parvis gsepe literis con- 
scriptum et correctionibus adeo abundans ut perdifficile lectu ") 
— or to certain changes made for the |)urpose of im])roving the 
literary style of the author, and of thus making his work more 
accei)table to his French readers. The chief difference between 
tlie text as given by Gerhardt, who has compared his impres- 
sion "with the original, so far as it is still extant," and that 
of the otiier editors consists in a transposition of the text in 
Book I., chap. I., a transposition Avhicli is fully indicated in 
the note at the point in the text of tlie translation where it 
occurs, and which is, I suppose, due to Gerliardt's fidelity to 
Leibnitz's original text. All the important textual variations 
are listed in the notes. 

Gerhardt's text, having been com])ared with the original, 
seems the nu)st trustworthy, and accordingly has been followed 
in this translation, excepting in a few instances mentioned in 
the notes, where it is manifestly erroneous from inaccurate 
proof-reading or other cause, and where the text of some other 
editor seemed more consistent or correct. Gerhardt has intro- 
duced into liis text the brackets, [ ], in which, " in the original, 
Leibnitz has enclosed the words of riulalcthes, who states the 
views of Locke," "perhaps as an indication that they are not 
his own;" and I have introduced them into the translation 
precisely as they stand in the text of Gerhardt, in order that 
the translation may conform to and re]n-esent as perfectly as 
possible Leibnitz's original text in its integrity. There seems 



TRANSLATOR'S PREFACE 



to be, however, little regularity or consistency in the employ- 
ment of these brackets, so far, at least, as I can discover upon 
comparison with Locke's treatise. 

Besides the editions and translations already named, the 
various separate editions of single works of Leibnitz, as also 
the various discussions of his philosophj^, theology, etc., and 
the monographs on different parts of the same, were occasion- 
ally consulted or referred to, so far as these were accessible 
or could be procured. Among the monographs, especial men- 
tion should be made of Professor John Dewey's most excellent 
Leibniz's New Essays concerning the Human Understanding . 
A Critical Exposition, 1888, in the series of German Philo- 
sophical Classics edited by Professor George S. Morris, and 
l)ublished by 8. C. Griggs & Co., Chicago; and of the earlier 
monograph of G. Hartenstein, Lodce's LeJire von der mensch- 
lichen Erkenntniss in Vergleiclmtuj mit Leibniz's liritik derselben, 
Leipzig, 18()1. 

The translation has purposely been made close rather than 
free, a philosophical treatise seeming properly to require a 
(doser adherence on the part of the translator to the author's 
form of thought and expression than a history, novel, or poem. 
"Whatever view may be taken on this point, — and I frankly 
admit that at least two views are possible and that each method 
of translation has its advantages and its disadvantages, its 
jierils and its successes, — the form and style of the Neio Essays 
nuike an elegant and forceful translation well-nigh impossible. 
Such a translation would necessitate the entire re-writing of 
Leibnitz's work, would, in fact, be a reproduction rather than 
a translation, a task 1 have not attempted nor felt it incumbent 
on me to attem])t. My aim has been simply to represent as 
I'aitli fully and as accurately as jjossible, and in as good English 
as its form and expression admitted, Leibnitz's exact thovight. 
Tlie style of Leibnitz in the Neiv Essays, especially in the 
al)breviations or abstracts of Locke's Essay put into the mouth 
of Pliilalctlies, is often abrupt and obscure and sometimes 
(n'(Mi uiigrammatical (cf., for example, JVe?o Essays, Book III., 
chap. II., § 18, ])age .'392, lines 6 and 7, and the note thereto, 
infra, ])age 7G8 ad Jin.). This condition of things is due partly 
to tlui form of the work, but chiefly to the method of its com- 
])osition (cf. Gerhardt's introduction, infra, page 8, and notes. 



TRANSLATOirs IMJF.rACE 



aiul the li'ttt'i's of Ivoibnitz cited by K;i.s])e in liis Preface, page 
V2, note (■), anil which he says, "1 found with the manuscript 
of the Xi'w Essays," and " give as I found them ''). A work so 
written, in spite of more or less revision, could not possibly 
be a finished treatise or a work of literary art like the Dia- 
logues of Plato, and the character of the work must of neces- 
sit}' be reflected in the translation. 

The notes aim to give the desirable or necessary biographical 
and bibliographical information regarding the persons and 
books referred to in the course of the work, so far as such 
information could be obtained; references to other pieces of 
Leibnitz, and occasionally to other authors, where the same 
topic is discussed; and explanations of a few terms thought 
to be obscure and the explanations of which are not generally 
known or easily accessible. The notes do not pretend to be a 
commentary on the text. Except in a few cases, the reader 
or student has purposely been left to gain his know^ledge of 
Leibnitz's views from Leibnitz himself. Extended com- 
mentary was impossible within the necessary limits of the 
volume, and accordingly was not included in the plan. The 
philosophical notes, therefore, confine themselves to a brief 
statement of Leibnitz's views and to brief criticism or indica- 
tion of criticism. The aim was to bring Leibnitz's great work 
witliin the reach of English students and to render it more 
easily accessible, with such annotation, literary and other, as 
would make it more acceptable to the student. 

All material taken from other authors has, so far as pos- 
sible, been verified and made the subject of such independent 
study as the ease seemed to demand. All references to 
authorities have been verified when possible, and very great 
pains liave been taken to secure perfect accuracy in all refer- 
ences. The citations have uuiformly been taken and the 
references made to the best editions, and usually to the latest, 
when these editions were accessible. Occasionally other works 
or editions are referred to because of their accessibility or for 
other evident reasons. For the convenience of those possess- 
ing different editions of Leibnitz's works, as well as for those 
wlio may have access to only one of them, reference is usually 
made, especially in the earlier notes, to all of the editions. 
Later this procedure seemed to encumber the notes with an 



TRANSLATOR'S PREFACE 



vinuecessary amoiiut of numerical reference, and it was for the 
most part discontinued. 

Attention is called to the Additions and Corrections as 
containing matter of importance, most of which was not 
obtained till after the portion of the book to which it refers 
was already in type, and which, therefore, could not be 
inserted in its proper place in the book, but had to be reserved 
to the end. 

The Indexes are intentionally full and complete and have 
been made with great care by Rev. Robert Kerr Eccles, M.D. 
There is no adequate index to Leibnitz's works, and none 
whatever exclusively devoted to the New Essays. The refer- 
ences thereto in the meagre index in Raspe's edition of the 
Philosophical Works, not generally accessible, and in the 
general index, full as it is, in Erdmann's edition, are by no 
means sufficient. It is hoped that the Indexes here furnished 
may prove adequate for the works of Leibnitz included in this 
volume, and that thus a beginning at least of an adequate index 
to Leibnitz's complete works shall have been made. 

In Appendix No. IV., infra, page 663, and No. V., infra, 
pages 674, 682, and 686, the numbering of the cuts is changed 
from that of the original text to conform to their proper 
numerical order in this book. The fact is here noted to pre- 
vent confusion in referring to the original. 

I gratefully acknowledge my obligations and express my 
thanks to all who have aided me in my long and arduous work. 
Especially to President E. B. Andrews of Brown University, 
for aid in the note on the term "quarto modo," page 455, 
and for the verification of references; to Professor Albert G. 
Harkness of Brown University, for aid in locating some of 
tlie Latin quotations in the New Essays; to Professor J. F. 
Jameson of Brown University, for the note, page 757, ex- 
plaining the term "Promoter," page 227; to Professor John 
M. Manly of BroAvn University, for infarmation and aid in 
the notes to the New Essays, Book III., chap. 2, page 294, 
notes 2, 3, page 295, notes 2, 3; to Professor E. B. Delabarre 
of Brown University, for aid in the note to page 122, lines 
1, 2, infra, pages 739-740; to Professor H. P. Manning of 
Brown University, for aid in the note on the "perles" of 
De Sluse, page 768; to Rev. R. H. Ferguson, for aid in the 



TRANSLATOR'S PREFACE 



same note, and in the revision of a portion of the Appendix; 
to Mr. Frank E. Thompson, A.M., Head-master of the Rogers 
High School, Newport, R. I., for aid in connection with a 
part of the subject-matter of the Dynamical Pieces in tlie Ap- 
pendix; to Professor licnjamin O. True of Rochester Theo- 
logical Seminary, for information and verification of references 
in connection with the notes to the New Essays, Book IV., 
chap. 19, page 599, note 2, 601, note 1, 602, note 1; to Pro- 
fessor F. A. March of Lafayette University, for the location 
of the Latin poetical rpiotation on page 603; to Professor Carl 
Schaarschmidt of Bonn University, for consulting books inac- 
cessible in this country, and for information kindly furnished 
by letter, and for his cordial interest in my work, as well as 
for the very valuable notes to his translation of the New 
Essays, without which mine never would have been written 
in their present form; to the various libraries whose resources 
have in one way or another been placed at my disposal, among 
which should be mentioned the Boston Public Library, the 
Boston Athenaeum, the libraries of Andover Theological Semi- 
nary, Xewton Theological Listitution, Rochester Theological 
Seminary, Brown University, Harvard University, Yale 
University through Professor Duucan, the Library of the 
Surgeon General's Office, Washington, D.C., and the Red- 
wood Librar}?^, Newport, R.I.; to the libraries particularly 
of Newton Theological Institution, Brown University, and 
Harvard University, for the long-continued loan of needed 
books ; to Professor Charles R. Brown of Newton Theological 
Institution for information and the verification of references; 
to my friend and former pupil Mr. Alfred R. Wightman, of 
the Morgan Park Academy of the University of Chicago, for 
the verification of references and aid in the revision of a 
portion of the Appendix; to Mr. Thomas J. Kiernan of the 
Harvard University Library, for special favors in the consul- 
tation of the library, for the loan of books from the same, 
and for information cordially furnished by mail; to Benjamin 
Rand, Ph.D., of the Department of Philosophy at Harvard 
University, for frequent consultation of authorities, verifica- 
tion of references and information furnished; to my friend 
Mr. Richard Bliss, Librarian of the Redwood Library, with- 
out whose competent criticism and constant advice and aid. 



TRANSLATOR'S PREFACE 



added to his comprehensive and accurate knowledge in many 
fields, and especially in bibliography, my notes would have 
been far less full and accurate than, I trust, they now are; 
and last but not least, to my wife for literary criticism in the 
revision of the translation and notes, and aid in the laborious 
task of proof-reading. Had I always accepted and adopted 
her criticism and that of Mr. Bliss, my work would doubtless 
rank higher as a piece of literature than is now possible. 

My thanks are also due and most heartily tendered to 
my publishers, Messrs. Macmillan & Co., for their uniform 
courtesy and long-suffering patience in the repeated but un- 
avoidable delays which have characterized the appearance 
of this book; and to J. S. Gushing & Co., of the Norwood 
Press, for the excellence of their work, and the pains they 
have taken to secure the greatest possible accuracy in the 
same, and for their uniform courtesy and long-suffering 
patience amid the vexatious delays unavoidably incident to 
the preparation of the notes and the correction of the proof. 

In editing the work of a thinker and writer so comprehen- 
sive as Leibnitz, it is impossible to escape all errors of fact or 
judgment. I have done the best I could in the circumstances 
in which I have had to work, away from large libraries and 
from the advice and criticism of fellow-students in the same 
lines. Competent and truth-loving criticism, and the correc- 
tion of any and all real errors will be thankfully received. 

With one sentence from Leibnitz's letter to Coste, June 16, 
1707, as significant of his character and illustrative of his 
spirit, more truth-loving than polemical, and as beautifully 
expressing the essence of true criticism, I close this Preface : 
" Mon but a este plustost d'eclaircir les choses, que de refuter 
les sentimens d'autruy," which, being interpreted, is: "My 
purpose has been to throw light upon things rather than to 
refute the opinions of another." 



Newport, R.I., April 11, 1896. 



Alfkkd G. Langlicv. 



LEIBNITZ'S CRITIQUE OF LOCKE ON" 
HUMAN UNDEESTANDING 



GERHARDT'S INTRODUCTION TO HIS EDITION OF 
LEIBNITZ'S NOUVEAUX ESSAIS 

\_Froin the German] 

Iisr the first philosophical treatise, Meditationes de Cognitione, 
Veritate, et Ideis,^ which Leibnitz published in the year 1684, he 
had firmly laid the foundations of human knowledge ; he de- 
clared adequate and at the same time intuitive knowledge as 
the most complete. At the end he adds : Quod ad controver- 
siam attinet, utrum omnia videamus in Deo ... an vero 
proprias ideas habeamus, sciendum est, etsi omnia in Deo 
videremus, necesse tamen esse ut habeamus et ideas proprias, 
id est non quasi icunculas quasdam, sed affectiones sive modifi- 
cationes mentis nostrae, respondentes ad id ipsum quod in, Deo 
perciperemus : utique enim aliis atque aliis cogitationibus sub- 
euntibus aliqua in mente nostra mutatio fit ; rerum vero actu 
a nobis non cogitatarum Ideee sunt in mente nostra, ut figura 
Herculis in rudi marmore. The assumption of these ideas 
slumbering in the mind, these innate ideas {aiujehornen Ideen; 
idees inn^es), Leibnitz regards as necessary in order to 
understand the nature of the mind. (Habet anima in se 
perceptiones et appetitus, iisque natura ejus continetur, he 
writes to Bierling, Hanoverte 12. Augusti 1711.^ Et ut 
in corpore intelligimus avTiTvirCav, et figuram generatim, etsi 
nesciamus, quge sint figurse corporum insensibilium : ita in 
anima intelligimus perceptionem et appetitum, etsi non 
cognoscamus distincte insensibilia mgredientia perceptionum 
confusarum, quibus insensibilia corporum exprimuntur.) 
He could therefore only prove the necessary truths, i.e. 

1 C. I. (;crli;inlt : Die jili/losajt/iiftrhcn Schri/fcn von (1. W. Leibniz. Vol. 
4, pp. 4'-!'2-42(>. .1. ]<;. l<]nlin:inn: (J. G. Lfihniiii Ojx'rii ]'/nl().v)phica, pp. 78- 
Hl. Translated by G(w)r^r iM. ])iiiic;ui, The I'liilonKfiliical Worls of Leibnitz, 
pp. 21-:V2, New Ilavcii : Tiittlc, Morehouse, & Taylor, 18^)0. — Th. 

2 The letter is IoiiikI in Gerhanll's e<l.. Vol. 7, i)p. 5li0-5(i2. — Tu. 

3 



LKIBNITZ'S ClUTIQUE OF LOCKE 



those which are kiu)\vii by demonstration, inasmuch as the 
senses indeed teach what happens, but not what necessarily 
happens. Such ideas innate to the mind are, according to 
Leibnitz, the conceptions of substance, identity, the true and 
the good. 

The writing of the man who questioned and rejected these 
fundamental principles of the system of Leibnitz could not 
faij^-te-lay claim to Leibnitz's entire attention. It was John 
^ckej^oru, 1632, at Wrington, near Bristol ; died, 1704, at 
(jSii^Tir the county of Essex, in the house of Sir Francis 
Masham, whose wife was a daughter of Cudworth), who in his 
celebrated work ("^An Essay concerning Human Understand- 
ing " ; in four books, London, 1690 ^) sought toMiscover also the 
originy-tha. certainty, and the extent of human knowledge, but 
who denied the existfuci' ol innate idt^is and }iriiicipk's, and 
affirmed tliat ilie mind is originally like an unwritten tablet 
(tabula fii-^a). In the hrst book of the work iianiril, Locke 

seeks to set forth the view thnt. thprp n.vp. nn in n iti' ideas, and 

therefore no innate principles and trutha; that the under- 
standing is by nature like an unwritten sln/et of paper. The 
second book contains the proof whence the understanding gets 
its ideas. Since there are no innate concepts and principles, 
the origin of all ideas can be only in experience. Experience, 
however, has a double sphere, that of external and of internal 
periLeptioa-:.-th.e fir&tXockej3alls Sensatioii; the second, Eeflec- 
tion. Sensation is the perception of external objects mediated 
through the senses ; reflection, the perception of the activities 
of the soul in relation to the ideas presented through the senses. 
Ideas are partly simple, partly complex. Simple ideas arise 
through the single senses, remoter ideas through more senses, 
as extension, form, motion, rest ; through reflection alone, for 

1 This work was already completed in the year 11)87 ; au abstract made by 
Locke hims(!lf appeared in the following; year, IHSS, translated into French in 
Leclerc's " Bildiotheqiie universelle," T. VIIL, pp. 49-142. The contents of 
the work, after it was completely pnlilished in the year 1600, was communi- 
cated in much detail by Led ere in the "Biblioth. Univers.," T. XVII., p. 399 
sq. TJie new editions, which already in tlie shortest time followed each other 
in quick succession in tlie years 1(>94. KiHT. 1(>99, 170.">, prove wliat a miichty 
impression T^ocke's work made upon cultivated circles. 1700 api^eared Coste's 
French translation of I^ocke's work: it was enriclied by Locke himself with 
improvements and additions. Leibnitz followed this French translation in 
I lie composition of his Novvcavx E.fsai.t. 



ON HUMAN UNDERSTANDING 



example, the idea of thought and will ; through union of sensa- 
tion and reflection, the ideas of power, existence, unity. The 
complex ideas are of three kinds : modes, substances, relations. 
The modes, i.e. the complex concepts, which contain nothing 
existing for itself, are either pure (simple modes), as space, time, 
or mixed (mixed modes), as thought, motion, power. By sub-"'" 
stances I>fj£l^p nn'1t^vstn.nf[a those combinations of simp lgH^eas 

or greupS of ideas, which iWff nrtnf> piuM r 1 ' nprm <i1iin 1iji|ii^<- , ]^ogig- 

that theyi correspond to definite, actually, existing things, so 
that the substance {.■^iibstrdfuni.) presupp osed fm- a nd in f.hp-m 
is considered ;is the point of union fo r the yest of thq nnn'^^-H" 
ent parts eontained in the grn.up of ideas. Of substance, man 
has no eleav conception; it is. according to Locke, worthless. 
According to him this conception is n(jt limited to single tilings, • 
but he extends it also to the collective ideas of many things ; 
thus an army, a herd of sheep, is just as- much a substance as 
a single man or one sheep. Relations arise from the comparison 
of many things with one another, as the conceptions of cause 
and effect, time — and place — relations, identity and diversity. 

Ideas and their combinations are apprehended in langua^^e ; 
therefore Locke begins in the third book with an investigation 
upon language, in so far as our knowledge, although relating 
to things, is bound to words, and words are an indispensable 
middle-term between thoughts and things. The extent and the 
certainty of knowledge are on this account conditioned upon 
the constitution and significance of words. In the fourth book 
Locke pronounces the concluding judgment upon 'the extent 
and the different grades of certainty in human knowledge.^ 

Leibnitz's attention was already turned from his own work to 
that of the English philosopher by the above-mentioned edition 
published by Locke himself in the "Bibliotheque universelle." 
When later Locke's work reached his hands, he threw off, as 
was his custom while he skimmed through the book, soin(> 
remarks;^ they folh)w h(u-e under the superscription: " Sur 

'For the foreuoiiijj; are of valiK^: Hartcnstciii, TyOf/y'.s Lrltrc von dcr 
meiixi-hHi-hf)) Er/:r)nitniss hi Vcr(/lci<'!uni</ mit Lcihniz'.t Krilik ilrrsilhcn. 
Lei])zii;;,. 18(11. — Uuliorwej^, Grundriss der Gi't<rhic/itr der PhUo.tdjdiie, ■> Tlicil. 
Berlin, 1880. 

2 They came into lieing iiftfu- the, year l()(l.">, since nieiilion is niaih' in thcni 
of T^iclve's Tr.ac^t npon Eiluciition : Thoiif/hls o», Education, London, KIIK!. 
Tliey were first pi'inted in SDivr. Farniliiir Lctlcrs betiveen Mr. Locke and 
Seii'v.r(d(>f hiH Fricndx, T,ondon, 170S, pp. l!M;-2n.'). 



LEIBNITZ'S CRITIQUE OF LOCKE 



I'Essay de I'enteudemeut humaiii de Monsieur Lock."^ Leibuitz 
sent it ill accord witli his pleasant custom to Thomas Burnett, 
with whom he corresponded.^ Through him they came to the 
knowledge of Locke, who, however, ujjon vain pretexts, de- 
clined every reply thereto.^ When Leibnitz received among 
others the communication from Burnett (July 20, 1698), that 
Locke had so far expressed his opinion that he for his part did 
not sufficiently understand Leibnitz's remarks upon his book, 
he resolved upon a remodelling of the same. Two fragments 
of the year 1698 are thereupon at hand ; they are printed here 
for the first time, under the superscription : '•' Echantillon * de 
Ketlexions sur le I. Livre de I'Essay de I'Eutendeinent de 
I'homme. — Echantillon de Reflexions sur le II. Livre." Leil> 
nitz again sent them to Burnett ; through whom Locke re- 
ceived them ; but this attempt also on Leibnitz's side remained 
without result, as appears from Burnett's letter to Leibnitz 
October 23, 1700. 

1 On Locke's Essay on Human Understanding. See infra, pp. i;5-19. — Tr. 

2 Leibnitz to Thomas Burnett, 7th-17tli March, 1090: " I found, also, finally, 
a rough draught which I had had copied formerly, of some remarks I made 
wlien rimning through the excellent essay of Locke upon Human Understand- 
ing; I take the liberty of sending you a copy." — Leibnitz to Th. Burnett, 
17th-2Tth July, l(j!)7: " What I sent you of my reflections upon the important 
book of Locke is entirely at your disposal, and you can communicate it to 
whomever it seems good to you ; and if it falls into his hands, or those of his 
friends, so much the better; for that will give him an opportunity to instruct 
us and to clear up the matter." 

3 Higlily characteristic is that which Burnett commimicated to Leibnitz 
upon the 2;?d of July, 1697: " I must tell you a joke of Locke's the other day, 
on this matter. We began to speak of the controversies of savants with those 
of this country. He said: 'It seems to me we live very peaceably as good 
neighbors of the gentlemen in Germany, for they do not know our books, and 
we do not read theirs, so that the tale (la [? Ze — Tk.] conte) {? le compte, the 
account) was well adjusted on each side.'" — On the other hand, we find 
a very dissenting judgment of Locke's upon Leibnitz and his remarks in 
his letter to Dr. Molyneux, of April 10, 1(597: "I must confess to you that 

Mr. L 's great name had I'aised in me an expectation whicli the sight of 

liis paper di<l not answer, nor that discourse of his in tlie 'Acta Eruditorum,' 
which he quotes, and I have since read, and had just the same thoughts of 
it, when I read it, as I find you have. From whence I only draw this infer- 
ence. That even great parts will not master any subject without great thinking, 
and even the largest minds have but narrow swallows." — Not less disparaging 
is Locke's judgment upon Leibnitz in the next letter to Molyneux, of May ,3, 
1()'.I7. — The correspondence lietween Locke and Molyneux is contained in the 
already quoted book: Simir Familiar Letters between Mr. Locke, etc. 

* Specimen of Retlectioiis on Book I. of the Essay on Human Understand- 
ing. Specimen of Reflections on Book H. See infra, pp. 20-25. — Tr. 



ON HUMAN UNDERSTANDINa 



In the year 1700 appeared the French translation of Locke's 
work published by Pierre Coste;^ it was prepared according to 
the fourth edition and contained accordingly the additions 
which Locke had made to the previous editions of his book. 
Leibnitz at once took occasion thereof to write a sketch for the 
" Monatliche Auszug^ aus allerhand neu-herausgegebenen, niitz- 
lichen und artigen Biichern," for the year 1700 (September, pp. 
611-63G). This follows here under ISTo. III.^ together with the 
supplement of the following year, 1701.* In this sketch Leib- 
nitz discusses two of the weightiest of Locke's additions, iilling 
two ^separate chapters, viz. : chapter 33 of the second book, 
wherein Locke treats of the Association of Ideas, and then 
chapter 19 of the fourth book, in which he discourses of 
Enthusiasm. 

Through the French translation Leibnitz first gained real 
access to Locke's work.^ He recognized the importance of its 
contents in its fullest extent ; at the same time the extremely 
large circulation and the universal recognition, which ex- 
pressed itself through the editions following each other in 
rapid succession, must have made upon him a deep impression. 
Evidently for these reasons Leibnitz conceived the plan of 

1 Essai Philosophiqixe concernaut I'entendemeiit liumain, oh Ton montre, 
quelle est reiiteiidiie de uos Conuoissances certaiiies et la maniere dont uous y 
parvenons, traduit de I'Auglais de Mr. Locke par Mr. Pierre Coste, sur la 
quatrieme edition, revue, corrigee et augmeiitee par I'Auteur. A Amsterd., 
1700. 4. This first edition of Coste's translation was not accessil)le to me : I 
have been able to make use of the second : Essai Philosophique concernant, 
etc. Traduit de I'Anglois par M. Coste. Seconde edition, revue, corrigee, et 
augmentee de quelques Additions importjiutes de TAuteur qui n'ont paru 
qu'apres sa mort, et de quelques Remarques du Traducteur. A Amsterd., 
1729. 4. 

^ I.e. " 'Monatliche Auszug' (Monthly Abstract) of the various newly imb- 
lished, ijrofitable, and pleasing books." — Tr. 

3 See infra, pp. 2(J-38. — Tb. 

* Tliis " Monatliche Auszug " appeared in three annual sets from 1700-170'j. 
Guliraner (Leibnitz's deutsche Schri/ten, 2ter Band) has tried to prove in n- 
very complete excursus that Leibnitz was the real editor of this Journal. 
Certainly tlie sketc-h of Locke's work originated witli Iiini. 

5 Leibnitz to Tliomas Burnett, 17th-27th July, 1(;!H>: "I could wish I had 
tlie same knowledge of tlie English language " (as of tlie I'^rcncli) ; " liut, nut 
having had the occasion for it, all I can (h) is to undcrsliind ]iassa))ly tlie books 
writt('n in this langiiago. And at tht; age at whicli I have arrived, I doul>t if 
I could ever make myself better ac(piaintcd witli it." — Leibnitz to Coste, of 
June 10, 1701: "I have followed your French version, because I tliought it 
l)roper to write my remarks in Frcsncli, since nowaihiys this kind of invtistiga- 
tiou is but little iu fashion iu the Latin Quarter." 



LEIBNITZ'S CRITIQUE OF LOCKE 



ans-\vering Locke's work with a more extensive writing. It 
grew out of the ofteu hastily-throwu-off remarks whicli lie 
occasionally put on paper in the years following that of 1700, 
in which he was not permitted to undertake any continuous 
work.' In order to obliterate the traces of this method of 
work, Leibnitz considered it advisable, before he published it, 
to submit his book, as to composition and style, to the judg- 
ment of a native Frenchman. This revision was protracted 
until the year 1705, as appears from a writing which has no 
signature.^ Another delay occvirred by reason of the fact that 
Leibnitz in the following year, 1706, entered into correspond- 
ence with Pierre Coste, the translator of Locke's work ; Coste 
told him (April 20, 1707) that the translation of Locke itself 
would be examined and furnished with important improve- 
ments; he would urgently advise him (Leibnitz) to put off 
the publication of his work until he obtained a knowledge of 
these changes of Locke. This further consideration, that he 
learned of the dissenting opinions of Locke in his corre- 
spondence with Molyneux, as also Locke's death, which had 

1 " I have made these remarks iu the leisure hours when I was travelling or 
at Herreuhausen, where I could not apply myself to researches which required 
more care" (besoin^ in sense of soin.^ — Tr.).i 

2 "The frequent diversions to which I have heen exposed have prevented 
me from pushing forward my remarks. Besides, I have been obliged to divide 
my time between the reading of your work and the commissions with which I 
have been entrusted by the Count de Schwerin, of which I must give account 
to him. Yon will find few remarks upon this paper; but I have taken the 
liberty of changing iu the work itself a very large number of places in reference 
to which I did not at all hesitate when I saw that I could do this without dis- 
arranging the rest of the writing. I have not touched what is properly called 
tlie style ; but the confidence with which you have honored me obliges me to 
say to you here that it greatly needs amendment, and that you seem too much 
to have neglected it. You know, sir, to what excess our French peoi)le have 
carried their well- or ill-founded delicacy. Too long periods are distastef lil ; 
an And (Et) or some other word too often repeated in the same period offends 
them ; unusual constructions embarrass them ; a trifle, so to speak, shocks 
them. It is proper, liowevcr, to accommodate yourself to their taste if you 
wish to write in their language; and, iu case you should decide to print your 
work, I believe you will do well to retouch it with a little more severity. I 
am certain that you will not be displeased at the freedom with which I speak 
to you, since it comes from a per.son devoted to your service." — Feb. 2, 
1705. 

' W. T. narris, editor of the " Journal of Speculative Philosophy," suggests that per- 
haps the reading was hexn/jne (work) — instead of besoiil. So that the passage read, 
" researches which required more work (or labor)." — Tit. 



ON HUMAN UNDERSTANDING 



already followed in the year 1704, altered Leibnitz's original 
plau.^ 

In order to obtain an easier entrance for his own ideas, and 
at the same time to make his reader familiar with those of 
Locke, Leibnitz had composed his w ork in the form of a di a- 
logue. Two friends, P hiitaletlie'iji and 'I'heophilm;, converse 
tog6tEer; the" hrst states tiie views of LookCj the seconds joiciS 
thereto his^own (Leibnitz's) remarks. This form of composi- 
tion Leibnitz thonght of abandoning. He writes to Thomas 
Burnett, May 26, 1706 : " The death of Locke has taken away 
my desire to j^ublish my remarks upon his works. I prefer 
now to publish my thoughts independently of those of 
another." On the other hand, he remarks, wellnigh it seems 
in tlie opposite sense, to the same, three years later. May 12, 
1709 : " My remarks upon the excellent work of Locke are 
almost finished ; although we are not of the same opinion, I 
do not cease to value it and to find it valuable." 

Leibnitz's work remained, in form at least, unfinished ; a 
magnificent torso, and unpublished.^ He turned to the compo- 

1 Leibnitz to Coste, June IG, 1707 : " The Rreat mei-it of Mr. Locke, and the 
general esteem which his work has with so much justice gained, united to 
some intercourse by letters which I have had tlie pleasure of having with my 
Lady Masham, caused me to emi^loy some weeks in remarks vipon this impor- 
tant work, in the hoj)e of conferring upon them with Mr. Locke himself. But 
his deatli sliocked me, and caused my reflections to be beliiudliand, although 
they are finished. My purpose has been to throw light upon things rather 
than to refute the opinions of another. I shall be delighted, however, sir, to 
receive the additions and con-ections of this excellent maji, in order to profit 
from them." — Leibnitz to Remond, March 14, 1714: "He (Hugony) has also 
seen my somewhat extended reflections upon Locke's work, which treats of 
Human Understanding. But I dislike to publish refutations of dead authors, 
although they might appear during their lifetime and be communicated to the 
authors themselves. Some minor remarks escaped me, I know not how, and 
were carried to England by a relative of the late Mr. Burnett, bishop of Salis- 
bury. Locke having seen them, spoke of them slightingly in a letter to 
Molyneux, wliich may be found among some posthun;ous letters of Locke. I 
learned his opinion of them only from tliis impression. I am not astonished 
at it : we differed a little too mucli in princij)lcs, and the views I advanced 
seemed to him paradoxical. However, a friend more biassed in my favor and 
less so in favor of Locke informs me that those of my reflections there inserted 
appear to him the best of the collection. I do not adopt this view, not Iiaving 
examined the collection." 

2 Over the Preface, which certainly was composed after the completion of 
the entire work, Ijcibnitz has written as tlif^ tit le of the work : Naitvemtx E.ssais 
sur I'entendement par I'Auteur du systcrne de rJIarmonie preestablie. In the 
Preface itself he leaves out tlic word "humain." The superscription of the 



10 LEIBNITZ'S CRITIQUE OF LOCKE 

sition of the "Theodicy." Foi- the first time, fifty years after 
his death, it was sent to the press in " (lOuvres i'liik)sophiqiies 
hitines et franqoises de feu Mr. de Leibnitz. Tirees de ses 
nianuscrits qui se conservent dans la bibliothetj^ue lloyale a 
Ilanovre, et publiees par Mr. Kud. Eric. Raspe. Avec une 
Preface de Mr. Kaestner, Professeur en Mathematiques a 
Gcittingen. A Amsterdam et a Leipzig, 1765." The present 
impression has been newly compared with the original, so far 
as it is still extant.^ The corrections in reference to the style 
proposed by the native Frenchman are not taken into consider- 
ation, in order not to obliterate Leibnitz's style of expression ; 
they relate, indeed, only to the first books. 

In the preface to his work, in w^iich Leibnitz has put 
together the points of difference between his system and that 
of Locke, he remarks in the first place that Locke's Essay upon 
Human Understanding is one of the most beautiful and vabia- 
ble works of its time ; that he has determined to make some 
remarks upon it, because he himself has considered the same 
subject for a long time, and deemed it a good opportimity to 
create a favorable entrance for his own ideas in this way. 
His own system differs, in truth, from Locke's considerably, in 
so far as Locke's is more closely related to Aristotle, his own, 
on the other hand, to Plato ; Locke's is more universally com- 
prehensible, his own more abstract. Meanwhile, by clothing 
his own remarks in the form of a dialogue between two per- 
sons, one of whom presents Locke's views, the other joins 
thereto his own, he hopes to avoid the dryness belonging to 
abstract remarks ; at the same time the reader is spared the 
labor of comparing the passages from Locke's essay under dis- 
cussion. — The^ iirst-4«ipGrtiLnt point— £'£-4iff£rence,_ wherein 
Leibnitz distinguishes h i^elffrom_J'"^kfi^ iisjji the ^ques - 
tion_v£lleth£x^-the--S£o^I_is_in_jtself empty like _a_to6MZa rasa, as 
Aristotle had already maintainecl7 and thatit receives every- 
thing through sense-perceptions and experience, or whether 

fourth hook runs thus: Nouveaux Essays siir V entendement ; in the case of 
the three first hooks we find the superscription : Nouveaux Essais sur V en- 
tendement humaine. 

1 In the original, Leihnitz has enclosed the words of Philalethes, who states 
the \iews of Locke, in [], perhaps as an indication that they are not his own. 
Raspe has omitted them. — Gerhardt's Note. In this translation Gerhardt's 
use of [ ] has heen strictly followed. — Tr. 



ON HUMAN UNDERSTANDING 11 

the soul originally has the principles of many conceptions and 
doctrines, as Leibnitz with Plato thinks. Hence arises another 
question, whether all truths depend upon experience, or whether 
there is still another principle. Th e senses are necessary for 
our actual k nowledge, but they sfive us only examplet^, -i p ij> - 
divMiial-tQl ths, which are not adequate for grounding the u ni- 
ve rsal ne p.pssity of a. f.ruth. T he necessary truths, which are 
fou ad in pure mathematics, appear to rest u pon other princi- 
ple s, whose proof depends not upon (.■xix-ricncr'TiiKl t he test i- 
mony of the senses^ — a. poinJiJiQ be wi'll roiisidrrcd. Log ic,. ^ 
metaphys ics^ ethics, are full of Euch truths, wliich can arise 
only Irom~s uch principles as ar e callqd innate,; It is neverthe- 
less possible, continues Leibnitz, tEaJE^-mj^ opponent is not - 
wholly remote from my view. For after he has rejected 
innate ideas in the first book of his essay, he begins the second 
book with the statement that the ideas which have not their 
origin in sensation arise through reflection. What, however, 
is reflection but a regard for what is in us and born in us ? 
Such are the ideas of being, unity, substance, etc. If, thinks . 
Leibnitz, an understanding with his opponent might easily, 
perhaps, be re-established in reference to the above, yet it 
might create more difficulty in reference to the affirmation 
that the soul does not always think, just as bodies do not_ 
always have motion. To this Leibnitz opposes the statement 
that bodies are always in motion and that a substance cannot 
exist without activity ; there are in the soul a multitude of- ' 
impressions too small to be separately distinguished, but which,' 
however, united produce an activity, altliough simply inarticu- 
late, like the noise of the waves. These little perceptions are 
of greater significance than we think. By" means of'these in- 
sensible perceptions the j^rc-ostablishcfl harmony between the 
soul and the body is explaincil. I n i he saiiLO manner Fhey are 
of great importance for Physics, for thereupon rests the law ' 
of continuity. These m hiute insensible perceptions are also 
the reason Avhy there are not two perfectly similar souls or 
things of the same kind. ^ ..^ 

An other point of difference between Leibnitz and Locke is- 
in refe rence to the conception of the nature of Matter. Locke" 
considered the smallest particles of matter to be rigid bodies, 
and therefore assumed that space is empty, else were any mo- 



LEIBNITZ'S CRITIQUE OF LOCKE 



tioii impossible. Leibnitz, on the other hand, supposes space 
to be lilled with a tiuid matter which is divisible to infinity ; 
he calls especial attention to the fact that Locke, who at first 
professed the gravitation theory of Newton constantly contested 
by Leibnitz, viz. : that bodies work upon each other from any 
distance whatever without touching, at a later period freed 
himself from this assumption of Newton. 

In discussing the concepts of space, time, and number, Locke 
had remarked that only with these concepts may that of infinity 
be united. Leibnitz agrees with him in this, that there is 
neither an infinite space, nor an infinite time, nor an infinite 
number, that in general the infinite is not given in that which 
is put together out of parts. But the true infinite, Leibnitz 
adds, is in the Absolute, which is without parts. From this 
proceeds the concept of the finite through limitation. 

In the beginning of the third book Locke had undertaken 
a discussion of language as the expression of the forms of 
knowledge. He had made thereby a distinction between nom- 
inal and real being. Leibnitz rejects this distinction as a 
perplexing innovation. Things, Leibnitz affirms, have only 
one essence, but different definitions of them, nominal and real 
definitions, are possible. 

The contents of the fourth book, in which is treated the 
knowledge of the truth, gives Leibnitz no occasion to raise an 
important point of controversy. In reference to the axioms, 
whose indispensableness to scientific investigations Leibnitz 
affirms, Locke contests, the former enters into a more protracted 
explanation. In like manner he turns against Locke's notion 
that the use of Logic is rather unfruitful. 



ON LOCKE'S ESSAY ON HUMAN UNDEESTANDING,^ 

1G96 

{_From the FrencW] 

I FIND so many marks of unusual penetration in what 
Mr. Locke has given us on the Human Understanding and 
on Education, and I consider the matter so important, that 
I have thought I shoukl not employ the time to no purpose 
which I should give to such profitable reading ; so much the 
more as I have myself meditated deeply upon the subject 
of the foundations of our knowledge. This is my reason for 
putting upon this sheet some of the reflections which have 
occurred to me while reading his Essay on the Understanding. 

Of all researches, there is none of greater importance, since 
it is the key to all others. The first book considers chiefly 
the principles said to be born with us. Mr. Locke does not 
admit them, any more than he admits innate ideas. He has 
doubtless had good reasons for opposing himself on this point 
to ordinary prejudices, for the name of ideas and principles 
is greatly • abused. Common philosophers manufacture for 
themselves principles according to their fancy ; and the 
Cartesians, who profess greater accuracy, do not cease to 
intrench themselves behind so-called ideas of extension, of 
matter, and of the soul, desiring to avoid thereby the necessity 
of proving what they advance, on the pretext tliat those who 
will meditate on these ideas Avill discover in them the same 
thing as they ; that is to say, that those who will accustom them- 
selves to their jargon and mode of thought will have the 
same prepossessions, which is very true. 

My view, then, is that nothing should be taken as first 
principles but experiences and the axiom of identity or (what 

1 Knliuumi, Lrihniiii Opcni Philosujilu'nt, pp. i:!()-i:')!). — 'I^t. 



14 LEIBNITZ'S CRITIQUE OF LOCKE [i 

is the same thing) contradiction, wliich is primitive, since 
otherwise tliere wouhl be no dili'ereuce between trnth and 
falsehood ; and all investigation would cease at once, if to 
say yes or no were a matter of indifference. We cannot, then, 
prevent ourselves from assuming this principle as soon as we 
wish to reason. All other truths are demonstrable, and I value 
very highly the method of Euclid, who, Avithout stopping at 
what would be supposed to be sufficiently proved by the so- 
called ideas, lias demonstrated (for instance) that in a triangle 
one side is always less than the sum of the other two. Yet 
Euclid was right in taking some axioms for granted, not as 
if they were truly primitive and indemonstrable, but because 
he would have come to a standstill if he had wished to reacli 
his conclusions only after an exact discussion of principles. 
Thus he judged it projjcr to content himself with having 
pushed the proofs wp to this small number of propositions, 
so that it may be said that if they are true, all that he says 
is also true. He has left to otliers the task of demonstrating 
further these principles themselves, which besides are already 
justified by experience ; but with this we are not satisfied in 
these matters. This is why Apollonius, Proclus, and others 
have taken the pains to demonstrate some of Euclid's axioms. 
Philosophers should imitate this method of procedure in order 
finally to attain some fixed principles, even though they be 
only provisional, after the way I have just mentioned. 

As for ideas, I have given some explanation of them in a 
brief essay printed in the " Actes des Sgavans " ^ of Leipzig for 
November, 1(384 (p. 537), which is entitled Meditationes de 
Cognitione, Veritate, et Ideis;^ and I could have wished that 
Mr. Locke had seen and examined it; for I am one of the most 
docile of men, and nothing is better suited to advance our 
thought than the considerations and remarks of clever per- 
sons, when they are made w^ith attention and sincerity. I 
shall only say here, that true or real ideas are those whose 

1 The " Afta Eruditorum," Lipsiae, 1682-1731. — Tr. 

2 Gcrhardt, Vol. 4, pp. 422-42fi; Erdmann, pp. 78-Sl. Translated in part by 
Sir William Hamilton, Lectures on Louie, Lect. X., II XXX., pp. 127-12'J, 
Amer. ed. ; and complete by George M. Duncan, The PhUosopliical Works 
of Leibnitz, pp. 27-.32, New Haven: Tuttle, Morehouse, & Taylor, ISitO; 
also by Professor Thomas Spencer Baynes, in the A^jpeudix to his edition 
of the Port Royal Logic. — Tk. 



I] ON HUMAN UNDERSTANDING 15 

execution we are assured is possible ; the others are doubtful, 
or (in case of proved impossibility) chimerical. Now the 
possibility of ideas is proved as much a iniori by demon- 
strations, by making use of the possibility of other more 
simple ideas, as a posteriori by experience ; f or what exists 
ca nnot fail to be possible . B ut primitive ideas are tho se 
whose possibility '■"- T^^.1'>"^ "'--cf,.oi^iQ^ miri wVii^v. ^^^ ^ in i-.i-nth 
np ^Tng e lse than the attribute!^ of GnrL 

.*^ I do not find it absolutely essential for the beginning or for 
the practice of the art of thinking to decide the question 
whether there are ideas and truths born with us ; whether they 
all come to us from without or from ourselves ; we will reason 
correctly provided we observe what I have said above, and 
proceed in an orderly way and without prejudice. The ques- 
tion of the origin of our ideas and of our maxims is not pre- 
liminary in Philosophy, and we must have made great progress 
in order to solve it successfully, I think, however, that I can 
say that our ideas, even those of sensible things, come from 
within our own soul,^ of which view you can the better judge by 
what I have published ' upon the nature and connection of sub- 
stances aiid what is called the union of the soul with the body. 
For I have found that these things had not been well under- 
stood. I am nowise in favor of Aristotle's tabula rasa; and 
there is something substantial in what Plato called reminis- 
cence. There is even something more; for we not only have a. 
reminiscence of all our past thoughts, but also a presentiment 
of all our future thoughts. It is true that this is confused, 
and fails to distinguish them, in much the same way as when 
I hear the noise of the sea I hear that of all the particular 
waves which make up the noise as a whole, though without 
discerning one wave from another. Thus it is true in a cer- 
tain sense, as I have explained, that not only our ideas, but 
also our sensations, spring from within our own soul, and that 
the soul is more independent than is thought, although it is 
always true that nothing takes place in it which is not deter- 



1 The French is : " de nostrc propre fotids." — Tr. 

2 In the "Journal des Savants," June, KiiJS. For the piece, cf. Gcrhardt, 
Vol. 4, pp. 477 .sry. (first sketch 470 nq.) ; and the portion of his introduction 
and notes referring to tlio same, Vol. 4, ])p. 414-417; I'h-dniann, pp. 124-128; 
cf. also pp. 129-i;J6. For tlie translation, Appendix, pp. . — Tu. 



10 LEIBNITZ'S CRITIQUE OF LOCKE [i 



mined, and nothing is found in creatures that (iod does not 
continually create. 

In Book II., which comes to the details of ideas, 1. admit that 
the reasons brought forward by Mr. Locke to prove that the 
soul sometimes exists without thinking of anything, do not ap- 
pear to me convincing, unless he gives the name of thoughts to 
those perceptions only which are sufficiently noticeable to be 
distinguished and retained. I hold that the soul (and even the 
body) is never without action, and that the soul is never with- 
out some perception : even in dreamless sleep we have a con- 
fused and dull sensation of the place where we are ; and of 
other things. But even if experience should not confirm the 
view, I believe that it may be demonstrated. It is much the 
same as we cannot prove absolutely by experience whether 
there is a vacuum in space, and Avhether there is rest in matter. 
Nevertheless, questions of this kind appear to me, as well as 
to Mr. Locke, to be decided demonstratively. 

I admit the difference which he puts with much reason be- 
tween matter and space ; but as for the vacuum, many clever 
people have believed in it. Mr. Locke is of this number. I 
was nearly persuaded of it m3'self ; but I gave it up long ago. 
And the incomparable Mr. Huygens, who was also for the 
vacuum and the atoms, began at last to reflect upon my 
reasons, as his letters can testify. The proof of the vacuum 
derived from motion, of which Mr, Locke makes use, assumes 
that body is originally hard, and that it is composed of a cer- 
tain number of inflexible parts. For in this case it would be 
true, whatever finite number of atoms might be taken, that 
motion could not take place Avithout a vacuum. But all the 
parts of matter are divisible and even pliable. 

There are also some other things in this second book which 
arrest my attention: for example, when it is said (chap. 17) 
that infinity should be attributed only to space, time, and num- 
bers. I believe, indeed, with Mr. Locke that, properly speak- 
ing, we may say that there is no space, time, nor number Avhich 
is infinite, but that it is only true that however great ^ may be 

1 Gerlmrdt's text seems here, for some reason, to he defective. It reads 
thus : " Mais qu'il est seiilement vray que pour ^rand que luy sans fiu," etc. 
Erdmann's seems tlie more correct, and is therefore followed in the translation. 
It reads thus: "Mais qu'il est seulemcnt vrai que pour grand que soit uu 
espace, iin tems, ou un nombre, il y en a toujours un autre plus grand que lui 



I] ON HUMAN UNDERSTANDING 17 

a space, a time, or a number, there is always another greater 
than it without end ; and that thus the true infinite is not * 
found in a whole composed of parts. It is none the less, how- 
ever, found elsewhere ; namely, in the absolute, which is with- 
out parts, and which has infiuence over compound things, 
because they result from the limitation of the absolute. The 
positive infinite, then, being nothing else than the absolute, it 
may be said that there is in this sense a positive idea of the / 
infinite, and that it is anterior to that of the finite. For the/ 
rest, in rejecting a composite infinite, we do not deny the 
demonstrations of the geometers de Seriebus infinitis, and par- 
ticularly what the excellent Mr. Newton has given us, not to 
mention my own contributions to the subject. 

As for what is said (chap. 30) de ideis adcequatis, it is 
allowable to give to the terms the signification which one finds 
pertinent. Yet without finding fanlt with Mr. Locke's mean- 
ing, I put degrees in ideas, according to which I call those 
adequate in which there is nothing more to explain, much the 
same as in numbers. Now all ideas of sense-qualities, as of 
light, color, heat, not being of this nature, I do not reckon 
them among the adequate. So it is not through themselves, 
nor a prioTi, but through experience, that we know their reality 
or possibility. 

There are further many good things in Book III. in which 
he treats of words or terms. It is very true that everything 
cannot be defined, and that sense-qualities have no nominal 
definition: thus they may be called primitive in this sense ; but 
they can none the less receive a real definition. I have shown 
the difference between these two kinds of definition in the 
meditation ^ cited above. The nominal definition explains the 
name by the marks of the thing; but the real definition makes 
known a priori the possibility of the thing defined. For the 
rest, I strongly commcmd Mr. Locke's doctrine of the demon- 
strability of moral truths. 

The foiirth or last book, which treats of the knowledge of 
truth, shows the use of what has just been said. I find in it, 
as well as in the preceding books, an infinite number of beauti- 

sans fin." p. 138 a. Cf. also Leibniz's New Essays cmir.erninr/ the Human 
Understanding. — A Critical Exposition, by John Dewo^y, Ph.D. i^p. 190. 
Chi(^aso: S. C. Gri.iLfss & Co., 1888. — Til. 

^ I.e. Meditationes de Cof/nitione, Voritate, et Idcis. — Tii. 
C 



18" LEIBNITZ'S CRITIQUE OF LOCKE [i 

fill vetlectious. To make suitable remarks upon them would 
be to make a book as large as the work itself. It seems to me 
that the axioms receive therein a little less consideration than 
they deserve. The apparent reason for this is that, excepting 
those of the matliematicians, we ordinarily find none which 
are important and solid: I have tried to remedy this defect. I 
do not despise identical propositions, and I have found that 
they are of great use even in analysis. It is very true that 
we know our own existence by an immediate intuition, and 
that of God by demonstration; and that a mass of matter, 
whose parts are witliout perception, cannot make a thinking 
whole. I do not despise the argument invented some centuries 
ago by Auselm, archbishop of Canterbury, which proves that 
the perfect being must exist; although I find that the argu- 
ment lacks something, because it assumes that the perfect 
being is possible. For if this single point were proved in addi- 
tion, the whole demonstration would be complete. 

As for the knowledge of other things, it is very well said, 
that experience alone does not suffice for a sufficient advance 
in Physics. A penetrating mind Avill draw more conclusions 
from some quite ordinary experiences, than another could draw 
from the most choice ; besides, there is an art of experimenting 
upon and, so to speak, (j^uestioning nature. Yet it is always 
true that we can make progress in the details of Physics only 
in ])roportion as we have experience. 

Our author shares with many able men the opinion that the 
forms of logic are of little use. I should be quite of another 
opinion, and I have often found that the paralogisms, even of 
mathematics, are the faults of form. Mr. Huygens has made 
the same observation. Much might be said upon this point, 
and many excellent things are despised because the use of 
which they are capable is not made of them. We are inclined 
to despise what we have learned in the schools. It is true we 
learn there many useless things ; but it is good to exercise 
the function della Crusca,^ i.e. to separate the good from the 
bad. 

1 "La C'ntsca, a celebrated academy of Florence, founded in 15S2, for the 
purpose of maintaining the purity of tlie Italian language, tliat is to say, of 
separjitiug the bran (rrusca) from the tloiu" : hence the name." Duncan's note. 
Philos. Works of Leibnitz, j). 378. 



i] ON HUMAN UNDERSTANDING 19 

Mr. Locke Ccan do this as well as any one whatsoever ; and in 
addition he gives us important thoughts of his own invention ; 
his penetration and fairness appear everywhere.^ He is not 
only an assayer, but he is also a transmuter by the increase of 
good metal he gives. Should he continue to present it to the 
public, we should be greatly indebted to him. 

1 Erdmauu omits this clause. — Tr. 



II 



SPECIMEN OF THOUGHTS UPON THE FIRST BOOK 
OF THE ESSAY ON HUMAN UNDERSTANDING 

[Fram the French^ 

In order to prove that there are no ideas born with us, the 
excellent author of the Essay on Human Understanding ad- 
duces experience, which shows us that Av^e need external occa- 
sions in order to think of these ideas. I agree with him, but 
it does not seem to me that it follows that the occasions which 
cause us to see them, cause them to spring into being. And 
this experience cannot determine whether it is through immis- 
sion of a species or by impression of outlines upon an empty 
tablet, or whether it is by the development of Avhat is already 
in us that we perceive ourselves. It is not extraordinary that 
there be somewhat in our mind of which we are not always 
conscious. Reminiscence shows us that we often have diffi- 
culty in remembering what we know, and in seizing what is 
already in the enclosure and possession of our understanding. 
This proving to be the truth in acquired knowledge, nothing 
prevents its being also true in the case of that which is innate. 
And, indeed, there is still more difficulty in perceiving this 
last, since it has not yet been modified and detailed by ex- 
perience, as is the acquired, of which often the circumstances 
remind us. 

The author undertakes to show in particular that impossibil- 
ity and identity, whole and part, etc., are not innate ideas. But 
I do not understand the force of the proofs he brings. I ad- 
mit that it is difficult to make men perceive distinctly these 
metaphysical notions, for abstraction and thought cost them 
^effort. But one may have in himself that which he has diffi- 
• culty in distinguishing there. Something else, howeverj than 
20 



I] ON HUMAN UNDERSTANDING 21 

the idea of identity is necessary to answer the (j^uestion, which 
is here proposed, viz. : Whether Euphorbus and Pythagoras 
and the cock/ in which the soul of Pythagoras dwelt for some 
time, were always the same individual, and it does not at all 
follow that those who cannot solve this question have no idea 
of identity. What is clearer than the ideas of geometry ? ■ 
Yet there are some questions which Ave have not yet been able 
to decide. But that one which considers the identity of Pytha- 
goras following the story of his metempsychosis is not one of 
the most impenetrable. 

Eegarding the idea of God, he brings forward examples of 
some nations who have had no such knowledge. M. Fabritius, 
a very distinguished theologian of the late Elector Palatine 
Charles Louis, has published the " L'Apologie du genre humain 
contre I'accusation de I'Atheisnie," in which he replies to such 
passages as are here cited. But I do not enter into this dis- 
cussion. Suppose there are men, and even peoples, who have" 
never thought of God; we may say that this fact proves only 
that there has not been an occasion sufficient to awaken in 
them the idea of the supreme substance. 

Before passing to the complex principles or })rimitive truths, 
I will say that I agree that the knowledge, or better, the actual 
consideration (envisagement) , oi ideas and trutlis is not innate, 
and that it is not necessary that we have distinctly known 
them in a former state of being, according to Plato's doctrine 
of reminiscence. ])ut the idea being taken for the immediate 
internal object of a notion, or of what the logicians call an 
incomplex term, there is nothing to prevent its always being 
in us, for these objects can subsist when they are not per- 
ceived. Ideas aiid truths may, furthermore, be divided into 
primitive and derivative : the knowledge of the primitives , 
does not need to be formed ; they must be distinguished only ; 
that of the derivative is formed by the understanding and by ' 
the reason upon occasion. However, we may say in one sense, 
tliat the internal objects of this knowledge, th;it is to say, the 
ideas and truths themselves, primitive as well as derivative, 
are all in us, since all the derivative ideas and all the truths 
deduced from them riisult from the relations of primitive ideas ' 
which are in us. But usage makes it customary to call innate 

1 Cf. I.oekc, /V//7'..s'. ICoz-Z-.s (liolm's cd.), Vol. 1, p. LSI .s^., and note. — Tu. 



22 LEIBNITZ'S CRITIQUE OF LOCKE [ii 

tho tvutlis to which credence is given us soon as they are 
heard, and the itleas whose reality (that is to say, the possibility 
of the thing which it represents) is of the number of these 
truths, and needs not to be proved by experience or by reason; 
there is then considerable ambiguity in this question, and it 
sutlices at the last to recognize that there is an internal light 
born with us, which comprises all the intelligible ideas and all 
tlie necessary truths which are only a result of these ideas and 
need not experience in order to be proved. 

To reduce, then, this discussion to something practical, I 
believe that the true end one should have is the determination 
of the grounds of truths and their origin. I admit that con- 
tingent truths, or truths of fact, come to us by observation 
and experience ; but I hold that necessary derivative truths de- 
pend upon demotistration, i.e. upon definitions or ideas, united 
with the primitive truths. And the primitive truths (such as 
the principle of contradiction) do not come at all from the 
.senses or from experience, and cannot be perfectly proved, but 
from the natural internal light, and this is what I mean in 
saying that they are innate. The geometers also have very 
well understood this. They could prove passably their proposi- 
tions (at least, the most important of them) by experience, and 
I do not doubt that the ancient Egyptian and the Chinese 
had such an experimental geometry. But the true geometers, 
above all, the Greeks, have desired to show the force of rea- 
son, and the excellence of science, by showing that they can 
in these matters foresee everything, by the internal light in 
advance of experience. It must also be admitted that experi- 
tence never assures us of a perfect universality, and still less 
of necessity. Some of the ancients laughed at Euclid because 
he proved what a fool even is not ignorant of (as they say), viz. : 
that in a triangle two sides together are greater than the third. 
But those who know what genuine analysis is, are much 
obliged to Euclid for his proof. And it is much that the 
Greeks, if less exact in other things, have been so much so in 
geometry. I attribute it to providence; and I believe without 
that we should hardly know what demonstration is. I also 
believe that it is principally in that respect that we are thus 
•far superior to the Chinese. 

But it is needful further to look a little at wjiat our clever 



ii] ON HUMAN UNDERSTANDING 23 

and celebrated author says in chapters 2 and 3, to sustain his 
point that there are no innate principles. He is opposed to 
the universal consent alleged in their favor, maintaining that 
many races doubt even this famous principle that two contra- 
dictories cannot be true or false at once, and that the greater 
part of the human race ignores it altogether. I admit that 
there are an infinite number of persons who have never made 
a statement of them. I have indeed seen authors who desired 
to refute them, apprehending them, without doubt, wrongly. 
But where shall we find one who does not avail himself of 
them in practical life, and who is not offended with a liar who 
contradicts him ? JSTevertheless, I do not ground myself wholly 
upon universal consent ; and as for propositions which are ap- 
proved as soon as they are proposed, I admit that it is not at 
all necessary for them to be primitive or proximate to them, 
for they may be very common facts. As for this statement 
which teaches us that one and one make two (which the author ■ 
brings forward as an example), it is not an axiom, but a defini-' 
tion. And when he says that sweetness is a different thing ■ 
from bitterness, he states only a fact of primitive experience, 
or of immediate perception. Or better, we have only to say 
that the perception of what is understood by the term sweet- 
ness is different from the perception of that which is under- 
stood by the term bitterness. I do not here distinguish at all 
the practical truths from the speculative ; they are always the 
same. And as we can say that it is one of the most manifest 
trutlis, that a substance whose knowledge and power are 
infinite should be honored, we can say that it emanates at 
once from the light which is born with us, provided one can 
give his attention to it. 



SPECIMEN OF THOUGHTS UPON THE SECOND 
1500K 

[From the French'] 

It is very true that our perceptions of ideas conu:; either 
from the external senses or from the internal sense, which may 
be called rcfiectinn : Init tliis reflection is not limit('(l to the 



24 LEIBNITZ'S CRITIQUE OF LOCKE [ii 

oitorations alone of the iniml, as is stated (chap. 1, § 4) ; it 
reaches even to the mind itself, and it is in the consciousness 
of self that we perceive substance. 

I admit that I am of the opinion of those who believe that 
the soul always thinks, although often its thoughts are too 
confused and too feeble for it to be able distinctly to remember 
them. I believe I have certain proofs of the continual activity 
of the soul, and I believe also that the body can never be 
without motion. The objections raised by the author (Book 
II., chap. 1, §§ 10 to 19) can be easily met by what I have just 
said or am about to say. They are based upon the experience 
of sleep, which is sometimes dreamless ; and in fact there are 
some persons who do not know what it is to dream. How- 
ever, it-is not always safe to deny everything that is notj^er- 
ceived. It is much the same as when there~afe people who 
deny the corpuscles and insensible motions, and laugh at the 
particles bemuse they cannot be proved. But some one will 
tell me that there are proofs which force us to admit them. 
I reply that there are in like manner proofs which compel us 
to admit perceptions which are not marked enough for us to 
remember them. Experience, furthermore, favors this view ; 
fo'flnstance, those who have slept in a cold place notice that 
they have had while sleeping a confused and feeble sensation. 
I know a person who wakes up when the lamp which he 
always keeps lighted at night in his room goes out. But here 
is something more precise, and which shows that if we did 
not always have perceptions, we could never be waked up 
"from sleep. Let a man who is sleeping be called by several 
persons at once, and let it be assumed that the voice of each 
by itself is not loud enough to awake him, but that the noise 
of all these voices together awakes him : let us take one of 
them ; it is very necessary that he be touched by this voice in 
particular, for the parts are in the whole, and if each one by 
itself does nothing at all, the whole will do nothing, either. 
Yet he would have continued to sleep, if the voice had been a 
single one, and that, too, without remembering that he had been 
called. Thus there are some perceptions too feeble to be 
noticed, although they are alwaj's retained, but among an infi- 
nite number of other small perceptions which we have con- 
tinually. For neither motions nor perceptions are ever lost; 



ii] ON HUMAN UNDERSTANDING 25 

both continue always, only becoming indistinguishable through 
composition with many others. One might reply to this 
reasoning, that each voice by itself effectively touches the 
body, but that a certain quantity of it is needed in order that 
the motion of the body may reach the soul. I reply, that the 
least impression reaches the entire body, and consequently to 
that part whose motions correspond to the actions of the soul. 
And accordingly no principle of limitation can be found, how- 
ever necessary a certain quantity may be. I do not wish to , 
insist upon the interest that the immortality of the soul has 
in this doctrine. For if the soul is passive, it is also without 
life, and it seems that it can be immortal only by grace and by 
miracle — a view which there is reason to disapprove. I admit, 
however, that our interest is not the measure of truth, and I 
do not wish to mix here theological reasons with those of 
philosophy. 



TIT 

[From the German'] 

Essai Pliilosophique concernaiit rEntendement Immain, ou Ton montre, 
quelle est roiitendtie de iios conuoissances certaines et la maiiiere doiit nous y 
pavveuons, traduit de I'Anglois de Mr. Locke par Mr. Pierre Coste, sur la 
quatrieiue edition, revue, corrigee et augmentee par I'Auteur. A Amsterd. 
1700 iu 4to. 

rbilosophiscber Versuch, betreffend deu Menscbliclien Verstand, ahvo 
gewiesen wird, wie weit sicb unsre gewisse Erkiiudtniissen erstreckeu, und 
auf wass Weise wir darzu gelangen; au.sz den Englischen iibersetzet von Hrn. 
Peter Coste naeb der vierten vom Autor selbst Ubersebeuen, verbe.sserten und 
-Aermebrten Edition. 5. Alpb. 12. Bog. 

It ' is uitnecessavy for tis to give a complete abstract of this 
notable book, after the author himself has relieved us of this 
task, since in the year 1688 he prepared such an abstract for 
Mr. Clerc for insertion in his " Bibliotheque universelle," ^ 
T. YIII., p. 49 sqq., before be gave it to the press. In the year 
1690 it appeared first in London in folio, and Mr. Clerc again 
published lengthy excerpts in the said " Bibliotheque univer- 
selle," T. XVII., p. 399. Soon afterwards a new English edition 
appeared, enlarged with many pieces, and in particular Avith 
an entire chapter ^ on Identity and Diversity, which he treats 
in an exceedingly clear and excellent manner. 

Ill the second edition mentioned, Locke acknowledges that 
he erred in the first edition when he assumed, in accordance 
with the common view, that what brings the Avill to any change 
of action in the course of arbitrary actions is the assurance of 
a much greater good. For when he considered the matter 
more carefully, he found that a present unrest which consists 
in desire or is constantly accompanied by the same, places its 
limits upon the will. For the reasons for this view, see Book 

1 From tbe " Monatliche Auszug," Sept. 1700, pp. (311-{i3G. — Tr. 
~ " Bililiotbeque universelle et bistorique," Amsterdam, 1G8G-1()S)3. — Tr. 
3 In tbe present edition tbis ebapter is 27 in tbe second book. — Gerbardt's 
note. 

26 



Ill] ON HUMAN UNDERSTANDING 27 

II., chap. 21. He will gladly, however, be informed of a bet- 
ter view. Some time after, a third, and in the year 1699, a 
fourth, edition appeared, in which last edition Locke either 
further explained his previous thoughts by many additions or 
supported them by wholly new grounds. Peter Coste made 
his translation on the basis of this edition, and when Locke 
sent him his manuscript, had worked upon the same for more 
than two years. Locke himself considered this translation a 
good one and presented his thanks accordingly, so that con- 
sequently it must be the more welcome by a great deal to us. 

To enumerate all the new additions would take too long; 
hence we Avill content ourselves with the mention of the two 
most important, which make two separate chapters, of which 
the first is Book XL, chap. 33, and treats of the Association of 
Ideas. 

Locke says there is almost no one who does not find 
something in the opinions, conclusions, and actions of other 
people which seems to him fantastic and extravagant, and is so 
in fact. Every one may have eyes keen-sighted enough to 
mark the least fault of this kind in the case of another, if 
only it may be distinguished from his own, and he himself may 
have sufficient understanding to condemn the same, although 
he also may have in his own opinions and his own conduct the 
greatest errors of which he might be aware, and of which, 
where not impossible, he may yet with difficulty be convinced. 

This arises, he continues, not merely from self-love, although 
this passion has often a great part therein. For one daily sees 
such people lying sick with the same disease, who are otherwise 
skilful and whole enough to make nothing of their own merits. 

This defect of reason is customarily ascribed to education 
and to the force of prejudice, and this, according to the common 
opinion, not without cause, but according to Locke's statement, 
this explanation reaches not to the root of the disease, and does 
not show completely its origin and peculiarity. 

He himself explains it as follows: Some of our ideas [his 
own words] have among themselves an exact correspondence 
and connection. The o1)ligation and highest perfection of our 
reason consists in tlie fact that it reveals such ideas and holds 
them together in the selfsame unity and correspondence as 
that which is grounded in their particular nature. There is 



28 LKIBNITZ'S CRITIQUE OF LOCKE [in 

besides this another bond of ideas which depends u})on chance 
or custom, so that the ideas which naturally are wholly unre- 
hxted become so exactly united in the minds (esprit ^ ) of some 
men, that they can with difficulty be separated from one 
another. They accompany one another constantly, and one can 
no sooner present itself to the understanding (intellectui) 
than the others or, indeed, more of them, so united are they, 
appear also, nor can they at all be separated from one another. 

This association of ideas, which the mind makes in itself 
either voluntarily or by chance, is the sole source of the defect 
of which we now speak. And as this strong union of ideas is 
not originally caused by nature, it is for this reason wholly dif- 
ferent in different persons, viz. : according to their different 
inclinations, education, and self-interests. 

That there are such associations of ideas, which custom 
begets in the minds of most men, no one, according to Locke's 
statement, can doubt, who with much earnestness considers 
himself and other people. And to this cause can perhaps with 
convenience and reason be ascribed the greater part of those 
symiDathies and antipathies which one finds among men, and 
which w'ork as strongl}^ and produce as regular effects, as if 
they were natural, which fact then makes them to be called so, 
although at first view they had no other origin than the chance 
connection of two ideas, which the strength of a first impres- 
sion, or of an excessively great compliance, so firmly united, 
that they always thereafter remain together in the mind of 
the man, as though only a single idea. Locke, however, in no 
respect denies that there are wholly natural antipathies which 
depend upon our original constitution and are born with us. 
He believes, however, that with proper consideration man 
would recognize the most of those which have been regarded 
as natural, as in the beginning caused by impressions which 
w^ere not heeded, whether they were suggested sufficiently 
early or through a ridiculous fancy. Locke notices incidentally 
the difference which may be made between natural and ac- 
quired antipathies, so that those who have children or who 

1 This word I have voluntarily retained here and for the most part in what 
follows, because it cannot he expressed quite clearly in German. — Leibnitz's 
note, Gerhardt, p. 27. 

Perhaps we should retain the word " esjn-it " in English. — Tr. 



in] ON HUMAN UNDERSTANDING 29 

must educate tliein, may see how much heed they shouLl take 
of this principle, and with what care this disorderly union of 
ideas in the mind of the youth should be prevented. 

He thereupon points out by some examples how such a union 
of ideas, which are not of themselves united, yet depend one 
upon another, is sufficient to impede our moral and natural 
action, yea more, our notions themselves. 

The ideas of goblins or of spirits agree as little with dark- 
ness as with light ; if, however, a foolish maid instils and 
aAvakens these different ideas in the mind of a child, as though 
they were connected with each other, the child during his entire 
life will perhaps not be able to separate them from each other; 
so that the darkness ever more will- seem to him to be accom- 
panied with these horrible ideas. 

If any one has suffered a grievous wrong on account of 
another, he thinks very often of the persons and the deed, and 
while he thus strongly or for a long time thinks thereupon, he 
at the same time glues these two ideas together so firmly, that 
he makes them almost one, as it were, and never remembers the 
person but that the wrong received also enters his head. And 
while he can scarcely distinguish these two things, he has just 
as much aversion for the one as for the other. Thence it 
comes, Locke adds, that hatred arises from slight and worth- 
less reasons, and quarrels are taken up and continued in the 
world. 

One of Locke's friends was wholly cured of madness by a 
certain man through a very painful operation, for which service 
he acknowledged himself under great obligation to him through- 
out his life, as he was so circumstanced that he required from 
no one a greater service during his life. Reason or gratitude 
might suggest to him what they would, yet he could never 
bear the sight of this surgeon. For as the sight of him always 
l)rought again to mind the idea of the very great pain which 
lie had been obliged to endure at his hands, he could not endure 
this idea, so violent were the impressions it produced in his 
mind. 

Many children hold their books, which were the occasion 
hereto, accountable for most of the ill treatment they endured 
at school, and they unite these ideas so avcII tliat they regard 
a book with groat disgiist, and all their life study and books 



30 LEIBNITZ'S CRITIQUE OF LOCKE [iii 

cannot win tlirir love, because to tliem readinj^, which might 
otherwise have greatly delighted them, became a genuine tor- 
ture, 

, An example notable for its singularity is the folloAving which 
an eminent man, who assured him he had himself seen it, re- 
lates to Locke : A young man had learned to dance very prettily 
and perfectly. There chanced to stand, howevei-, in the hall 
where he first learned, an old trunk, the idea of which com- 
bined so imperceptibly with his turns and steps in the dance, 
that although he could dance incomparably well in this hall, 
he could do this only when the old trunk Avas there ; in other 
places, however, he could not dance at all, unless tlie old trunk 
itself or one like it stood in its accustomed place. 

The habitus intellectuales which are contracted through such 
association of ideas, are, as Locke further informs us, just as 
strong and numerous, even though very little heeded. Silp- 
posing the ideas of being and matter were very strongly united, 
either by education or by an excessively great application to 
these two ideas, according as they are combined in the mind, 
what notions and reasonings would they not produce concern- 
ing different spirits ? If a custom accepted from childhood 
up had united a form or figure Avith the idea of God, into what 
absurdities would such a thought in the contemplation of deity 
not plunge us ? We shall no doubt find, Locke adds, that it 
is nothing else than similar ill-grounded and unnatural combi- 
nations of ideas, which break the path for the many conflicting 
sects in philosophy and religion ; for it is not to be supposed 
that each meinber of those different sects is Avillingly deceived, 
and against his better knoAvledge and conscience rejects the 
truth demonstrated to him by clear evidence. It is indeed 
certain that sometimes interest assists greatly in this sort of 
thing, yet no one could affirm that it could captivate and lead 
astray whole societies, so that they all, none excepted, should 
affirm plain and deliberate falsehoods. For it must be that 
some at least do what others pretend to do, viz. : seek truth 
sincerely. 

Therefore there must be something which blinds their un- 
derstanding and hinders them from recognizing the falsehood 
of what they consider as pure and refined truth. If noAv Ave 
investigate accurately Avhat takes reason prisoner and darkens 



Ill] ON HUMAN UNDERSTANDING 31 



the understanding of otherwise sincere people, we find that it 
is simply and solely some free ideas, which, properly speaking, 
really have no bond among themselves, but which, by educa- 
tion, custom, and uninterrupted action on their part, are so 
united in the mind that they can no more be separated and 
distinguished from one another than a single idea. Thence it 
comes, Locke continues, that often the crudest things are 
taken for worthy opinions, absurdities for demonstrations, and 
intolerable and absurd results for strong and fluent reason- 
ings. 

The other chapter we promised to present, treats of Enthu- 
siasm, and is the 19th in the 4th book. Locke's thoughts 
thereupon are as follows : — 

Whoever will earnestly seek for truth must first before all 
things acquire a love for it. Whoever does not love the truth, 
to him we must necessarily attribute the opposite. Hence we 
can rightly say, that among those who pretend to seek it, 
there are very few who really love it. We may recognize a 
genuine seeker of the truth, since he does not assume for a 
statement any greater certainty than the proofs upon which 
he grounds it warrant. Whoever steps beyond this limit lays 
hold of the truth not out of love for it, but from another indi- 
rect purpose. Por while the unquestionable clearness of a 
statement truly consists in the evidence for it (excepting 
those which are sufficiently clear of themselves), yet it is 
plain that so far as space is given to assent beyond the unques- 
tionable clearness of a proposition, the remaining portion of 
the assurance is not drawn from love for the truth, but from 
another passion. For as it is impossible that love for the 
truth can bring any one to give to any proposition an assent 
greater than that certified by the truth itself, just so is it also 
impossible that any one oiit of love for the truth can assent to 
a statement in view of evidence of such a character that from 
it he cannot see whether the statement is true; which Avould 
be actually equivalent to the assumption that tlie proposition 
is a truth because possibly, or, indcHid, })robably, it seems not 
to accord witli the trutli. 

Locke adds, it follows indisputably from this evil disposi- 
tion of the mind, that men assume the authority to dict.ntci 
their own opinions to others. For hcnv slnndd one avIio has 



32 LEIBNITZ'S CRITIQUE OF LOCKE [in 

imposed on his own belief, not be willing also to impose on 
the belief of others ? How is it to be expected that one will 
use valid arguments and proofs in dealing with others, who is 
not accustomed to use them in dealing with himself, who does 
violence to his own powers, who tyrannizes over his own mind, 
and misuses the advantage which truth alone has, viz. : that it 
assents to nothing but what is indisputably true ? 

After Locke has laid this foundation, he proceeds to the in- 
vestigation of Enthusiasm, to which some people ascribe as 
much power as to faith and reason, and would establish revela- 
tion without the aid of reason, whereby, however, they would 
at once destroy both reason and revelation, and without any 
reason erect in their place the fancies forged in their own 
brain, which they choose as the plumb-line of their opinions 
and conduct. Reason is nothing else than a natural revela- 
tion, whereby God bestows upon men that portion of truth 
which he has poured into the capacity of their natural powers. 
Revelation is natural reason, enlarged by a new set of discov- 
eries flowing immediately from God, the ground (raison) of 
which is the truth by testimony and proof they offer that 
these discoveries actually come from God.^ AVhoever, there- 
fore, destroys reason to make room for revelation, extin- 
guishes both these lights at the same time. As, however, men 
find that an immediate revelation is a much easier means of 
strengthening their opinions and of directing their conduct 
than the labor of arranging all according to strict reasoning, 
which is usually irksome, prejudiced, and for the most part 
without successful progress ; so it is not to be wondered at 
that they often pretend revelations and persuade themselves 
that God directs them in particular as regards their actions 
and opinions, and especially in those things which they cannot 
justify by the principles of reason. If their minds are once 
possessed with this thought, the most absurd opinions which 
are firmly impressed upon their fancy, must seem to be ilhi- 
minations coming from the Spirit of God and having divine 
authority. Every extraordinary thing to which they are led 
by a strong impulse, they consider as certainly a divine call 

1 On tliis whole discussion, rf. an article by the translator entitled "Reve- 
lation, Inspiration and Autliority," in "The Andover Review," April 1891. 
— Tr. 



Ill] ON HUMAN UNDERSTANDING 33 

which they must follow, and as a command from on high in 
whose execution it is impossible to err. 

This is, properly speaking, what is meant by Enthusiasm, 
which is not adjusted to reason nor to divine revelation, but 
springs forth only from the imagination of a heated and con- 
ceited spirit, aiid which, as soon as it has taken a little root, 
plays much more strongly upon the opinion and actions of 
men than reason or revelation separately or together. 

Although now the extravagant actions and opinions, wherein 
enthusiasm has involved men, should spur them on to be more 
on their guard and to avoid the false 2^'>'i^^cfpici) which lead 
astray both their belief and their conduct; yet through its 
love for the extraordinary, through its ease and illumined by 
its glory, and through its extraordinary paths to knowledge it 
has come to pass that the laziness, ignorance, and vanity of 
many are so tickled, and they are brought to such a point, that 
after they are captivated by such ways of an immediate reve- 
lation, of an illumination without search, of a certainty with- 
out proof and investigation, it is very difficult to bring them 
out of it again. 

They are transported beyond reason, and reason in their 
case perishes. They see a light infused into their understand- 
ing and can no longer be deceived. This light visibly appears 
as the clearest sunbeam and requires no other proof than its 
own clearness. They feel, according to their statements, the 
hand of God moving them within ; they feel the impulses of 
the Spirit, and cannot be mistaken in their feeling. Thus 
they persuade themselves that reason has nothing to do with 
what they see and feel in themselves. The things which they 
clearly experience are beyond all doubt, and need no proof; 
and so of all the rest of their strange talk. They are sure of 
these things because they are sure of them, and their opinions 
are correct because they are firmly fixed in their mind. For 
this is the upshot of their words when stripped of the meta- 
phors of hear 17)// and feeling in which they are clothed. 

Locke investigates the ground of this inner light and feel- 
ing, upon which these people so firmly base themselves, and 
speaks thus : Is this seeing of the light a perctqjtion of the 
truth of a certain particular statement, or perhaps of this, that 
it is a revelation from God? Is this feeling a perception of 
I) 



34 LEIBNITZ'S CRITIQUE OF LOCKE [in 

an inclination, wbicli comes from a fancy to do something, or 
from the spirit of God, which begets in it this inclination? 
These are two wholly different feelings, which must be care- 
fully distinguished from one another if we would not deceive 
ourselves. I can perceive the truth of a proposition; but I 
cannot thereby know as yet whether it is an immediate revela- 
tion from God. I can i:)erceive the truth of a projjosition in 
Euclid without its being or my knowing that it is a revelation. 
I may also know that I did not attain this knowledge through 
natural means, thence may indeed conclude that it is revealed 
to me, but I cannot thereby yet know it is a revelation from 
God; because there may be minds which without a divine 
commission for this work arouse these ideas in me and set 
them in such order in my mind that I may perceive their con- 
nection. So that the knowledge of a proposition, which enters 
my head, I know not how, is thus not an evidence that it 
comes from God. Still less is a firm persuasion that this 
fancy is true, a certain evidence that it comes from God, or 
that it is true. 

We may call such a fancy sight or liglit, yet it is nothing 
more than belief and confidence.^ For if the proposition under 
discussiou be one which they have imagiued, but do not know 
to be true, it cannot be seeing, but Relieving. One may also 
give to such fancy any name he pleases. What I believe, I 
must put forth as true upon another's testimony, and must 
know certainly in the case that this testimony is given ; for 
without this my belief would be groundless. I must see 
whether God reveals this to me, or Avhether I see nothing. 
Thus the issue is, that I know how I am to know that God 
reveals something to me, that this impression in my soul 
occurs through the Holy Spirit, and that consequently I am 
bound to follow it. If I do not know this, my confidence, 
great as it may be, is without the least foundation, and all the 
light with which I perceive myself illumined, is but enthusi- 
asm. For whether the proposition supposed to be revealed, 
be evidently true in itself, or visibly probable, or whether it 
be difficult to vindicate it by the ordinary paths of knowledge, 
this must nevertheless before all things be clearh^ established 
and proved, that God has revealed this proposition, and that 

1 The German is " Credulitiit imd Confideutz." — Tr. 



Ill] ON HUMAN UNDERSTANDING 35 

what I take as a revelation certainly comes of itself into my 
mind, and is no illusion, which, some one else has thrust in or 
my own fancy has awakened. Until one has come this far, 
all confidence that this revelation comes from God is a mere 
conjecture, and all this light which dazzles one is nothing but 
an ignis fatuus, which will unceasingly lead us into this circle : 
This is a revelation because I finnh/ believe it; and I believe it 
because it is a revelation. 

It follows from this that those who imagine that they have 
such revelations of this or that truth must be assured that it, 
is God who has revealed it to them. For to say, as they gen- 
erally do, that they know it by the light which it brings with 
it, which shines and flashes in their souls, and which they 
cannot resist, means only that it is a revelation because 
they believe it certainly is one ; since all the light of which 
they speak is nothing but a strong imagination which is firmly 
fixed in their mind, and yet has not the least ground that it is 
a truth. For they must consider that to assume accepted 
grounds as reasonable and as a proof that it is a truth, is a nec- 
essary acknowledgment that they have no such (grounds).^ 
Because, if they have such, they receive this truth uo longer 
as a revelation, but as a truth established upon common 
grounds. And if they believe it to be true, because it is no 
revelation, and if they have no other reason to prove it a 
revelation than simply because they are completely persuaded 
of its truth, without any other ground and only on account of 
this fancy, then they believe it to be a revelation only be- 
cause they strongly believe it to be a revelation. Who does 
not see that if we build upon such grounds, we make our own 
fancy the only rule of our opinions and conduct, and conse- 
quently subject ourselves to the strangest errors and vexa- 
tions. For once for all the strength of our opinions is no 
proof of their correctness. Meanwhile men can approve an 
error as a truth, as may be seen in the case of those zealous 
people who maintain in the sharpest manner two propositions 
contrary to one another. 

In reference to wliicli Locke well says, that if the light, 

1 The text is: " Deim dieses miissen sie vor raisonublo uiul von eiiiisem 
lieweise iialten, der da zeige, dass es eiiie Warlieit scy, tjeiioiinncne Oriiiido 
aiiuehineii, dass sie erkouiieu iiiiissoii, wie sie clei'i;lciclirn iiiclil liabcu." — Tii. 



30 LEIBNITZ'S CRITIQUE OF LOCKE [in 

which oveiy one thinks lie has in himself, and which in this 
case is nothing but the strength of his own opinion, be a proof 
that his thought comes from God, then we must 'conclude that 
all contrary opinions have the right to pass as divine inspira- 
tions ; and God would be not only the father of light, but also 
of wholly opposite lights, which lead men in ways wholly 
contrary. 

Therefore Locke concludes that he who does not wish to 
fall into a mass of disorderly delusions and errors must first 
^test thoroughly this inner light which offers itself as a guide. 
God, he says, does not destroy the man when he makes a 
prophet. He leaves all his faculties in their natural condi- 
tion, so that he may thereby judge whether the inspirations 
which he feels within have sprung from God or not. If God 
will have us acknowledge the truth of a proposition, he permits 
us to see this truth either through the ordinary paths of nat- 
ural reason, or he makes us know that it is a truth which we 
must receive upon his authority, while he convinces us by 
certain marks which reason cannot reject that it comes from 
him. I will not, however, Locke adds, say by this, that we are 
to examine by reason whether a proposition thus revealed to 
us by God may be proved by natural principles, and if not we 
may reject it; but I will say, that we must consult reason and 
by its aid see whether it be a revelation from God or no. 
For if reason finds it to be a divine revelation, it declares for 
it as such from that hour on as well as for any other truth, 
and makes it one of its rules, so that it cannot be rejected. 

If this inner light, or a proposition which presents itself in 
our mind as revealed, accords with the principles of reason or 
with the word of God which is an attested revelation, we have 
the warrant of reason for it, and may accept this light as true, 
and direct our faith and walk accordingly. If, however, this 
light has the witness or proof of neither of these rules, we 
cannot consider it as a revelation ; nay more, as a truth. For 
if we at the same time believe it to be a revelation, that does 
not, however, make it so ; it may, however, be shown by some 
other mark to be really a revelation. The old prophets, when 
they were to receive revelations from God, had other proof 
than the inner light which assured them that these revelations 
reallj^ came from God. They imagined not only that their 



Ill] ON HUMAN UNDERSTANDING 37 

imaginations came from God, but they had also external signs 
Avhich convinced them that God was the author of their reve- 
lation. And if they were to convince others of the same, they 
received beforehand a special power to set forth the truth of 
the commission given them of Heaven with visible signs. Thus 
Moses saw a burning bush which was yet not consumed and 
heard a voice out of the bush. This was something more than 
an inuer feeling of an impulse to free the children of Israel 
from the hands of Pharaoh. Yet, Moses did not believe that 
this was enough to warrant him in going into Egypt with God's 
commission ; until God assured him by still another miracle, of 
the rod changed into a serpent, that such was his real will, and 
granted him the power to work precisely similar wonders in 
the sight of Pharaoh. Precisely similar was it in Gideon's 
case. These and other examples of the old prophets^ show 
sufficiently that they did not believe that an inner vision or 
their own imagination attested by no other affirmation a suffi- 
cient evidence that their imagination came from God; although 
the Scripture does not everywhere mention that they always 
asked for or received such proofs. 

These few passages from the clever work of Locke, under 
the guidance of the accurate translator Coste, we have brought 
forward as specimens. Perhaps we shall have further oppor- 
tunity to speak of it, when the Latin translation, with which 
some one ^ is now occupied in England, is published. 



In the " Monatliche Auszug " of the year 1701 is found (pp. 
73-75) the following addition to the foregoing sketch : — 

What Locke says of the connection and accompaniment of 
ideas is not to be despised, and serves often to arouse the emo- 
tions; as for errors and false judgments, however, they spring 
from other contiguous and peculiar causes, viz.: that one 
assumes false principles, and imagines that he once had proof of 
them in his mind, Avithin which now a lapse of memory occurs; 
and then from incorrect conclusions which he produces from 
these principles assumed as known, because he gives not the 
time and labor to investigate all in a formal and orderly way. 

1 Bun'idj;e of Dublin. Tlio version appeared in 1701. — Tii. 



;]8 leie:sitz's critique of LOCKE [hi 

Meaiiwliile it is true that the emotions greatly assist this credu- 
lity coueeruiug principles and carelessness in false deduction ; 
for one believes and easily draws the conclusion he would gladly 
have. It is besides noticeable in this book of Locke's, that in 
his last writings against the Rev. Lord Bishop Stillingfleet he 
has changed a large part of his opinions concerning the nature 
of the body contained in this Teatanien or Essay on Human 
Understanding ; while in this Tentamen he held opinions, in 
common with modern philosophers, especially the followers 
of Descartes and Gassendi, that in the body nothing is to be 
met with but size, solidity or impenetrability, and motion or 
change ; now, however, he begins to hold the opinion that there 
is something to be found therein not revealed through these 
qualities. He repudiates, besides, in this essay innate ideas 
and the natural light, but appears not to distinguish suffi- 
ciently the necessary truths arising from possibility, from those 
others whose ground must be assumed from the experience of 
realities, and thus must be drawn from without. 

Thus he accepts the tabula rasa of Aristotle, rather than 
the implanted (ideas) of Plato. It is true that we do not 
come upon thoughts in these most abstract matters, without 
external sensations, but in the case of these necessary truths, 
such sensations serve more as a reminder than as a proof; 
which (proof) must come simply and solely from internal 
grounds, as those do not sufficiently understand who deal little 
in demonstration proper. 



NEW ESSAYS ON THE UNDERSTANDING 

By the Autiiok of the System of Pke-Established 
Hakmony 



PREFACE 

The Essay on the Understanding, by a distinguished English- 
man, being one of the most beautiful and esteemed works of 
this period, I have resolved to make some remarks upon it, 
because having sufficiently meditated for a long time upon 
the same subject and upon the greater part of the matters 
therein touched upon, I have thought that it would be a 
favorable opportunity to publish something under the title of 
" New Essays on the Understanding," and to procure a favor- 
able reception to my thoughts, by putting them in so good 
company. I ^ have thought also that I could profit from the 
labor of another not only to lessen my own (since in fact it 
is less difficult to follow the thread of a good author than to 
work wholly independently), but further to add something to 
what he has given us, which is always easier than to start from 
the beginning ; for I think I have cleared up some difficulties 
which he had left in their entirety. Thus his reputation is an 
advantage to me ; having for the rest a disposition to render 
justice, and very far from wishing to diminish the esteem in 
which this work is held, T would increase it, if my approval 
carried any weight. It is true I often differ in my views (from 

1 Gorhardt's text reads as follows: "J'ai cru eiicor poHvoir profiter du 
travail d'autruy non seulement pour dimiiuKU' le mien (puisqu'eii elToct 11 y a 
mollis de peine a suivre le til d'lin boii auteur qu'a travailler a iionveaux frais 
en tout), mais eneor pour adjouter quelque chose a ce qu'il nous a doiinc, ce 
qui est tousjours plus facile que de commencer ; car je (;rois d'avoir leve 
quelques diflficultes qu'il avoit laissees on leur entier. Ainsi sa i-epiitation 
ra'cst avantaguese ; estant d'ailleurs d'humeur a rendro justice et bicTi loin do 
vouloir diminuer I'estiTuo qu'on fi pour cet ouvrago, jo raccroistrois, si mon 
api)robatioii estoit de quelque jioids. Tl est vray que je suis souvent d'un autre 
avis, mais bien loin de discoiivcuir du merito des Ecrivains celebres, on leur 
rend temoii;na.s;e, on faisant connoistro en qiioy ct pour quoy on s'('loii,aio de 
leur sentiment, quand on juge neeessaire d'empecbor que leur autorite no 
prevaille h, la raison en quelques points de consequence, outro qu'cn satisfaisant 
:i de si exccllens liommis, on rend la vi'rite plus recevable, ot il faut supposer 
que, e'est principalenient poui' elle qu'ils (ravaillcnl ." — 'I'u. 

11 



LEIBNITZ'S CRITIQUE OF LOCKE 



liini'), Init very far from donying the merit of celebrated 
writers, we bear witness to it, by making known in what and 
why we differ from their views, when we judge it necessary 
to ])revent their authority from prevailing over reason on some 
important points ; besides, by satisfying such excellent men, 
we render the truth more acceptable, and it must be supposed 
that it is principally for truth that they labor. 

In fact, although the author of the Essay says a thousand 
beautiful things which I commend, our systems are very dif- 
ferent. His has more relation to Aristotle, mine to Plato, 
although we both differ in many things from the doctrine of 
these two ancient philosophers. He is more popular, and I 
am compelled sometimes to be a little more acroamatic and 
more abstract, which is not an advantage to me, especially 
when Avriting in a living language. I think, nevertheless, that 
by making two persons speak, one of whom sets forth the 
views drawn from the Essay of this author, and the other 
joins thereto my observations, the parallel will be more to the 
liking of the reader than wholly dry remarks, the reading of 
which would be interrupted at every moment by the necessity 
of recurring to his book in order to understand mine. It will 
nevertheless be well still to compare sometimes our writings, 
and not to judge of his views except by his own work, although 
I have ordinarily preserved its expressions. It is true that the 
constraint, which another's discourse, whose thread must be 
followed, gives in making remarks, has prevented me from 
thinking to secure the charms of which the dialogue is sus- 
ceptible ; but, I hope the matter will make amends for the 
defects of the style. 

Our differences are upon subjects ^ of some importance. The 
question is to knoAv whether the soul in itself is entirely empty 
as the tablets upon which as yet nothing has been written 
, (tahnla rasa) according to Aristotle, and the author of the 
Essaj^, and whether all that is traced thereon comes solely 
from the senses and from experience ; or whether the soul con- 
tains originally the principles of many ideas and doctrines 
which external objects merely call up on occasion, as I believe 

1 Erdraann ami Jacques read : " que lui," which does not occur in Gerhardt's 
text.— Tr. 

'- Erdmann and Jacques read : "objects." — Tr. 



ON HUMAN UNDERSTANDING 43 

with Plato, and even with the schoolmen, and witli all those 
who interpret in this way the passage of St. Paul (Rom. 2 : 15) 
where he states that the law of God is written in the heart. 
The Stoics call these principles ^ j;)rolepses, i.e. fundamental 
assumptions, or what is taken for granted in advance. The 
Mathematicians call them general notions (/coivat eVvotat). Mod- 
ern philosophers give them other beautiful names, and Julius 
Scaliger in particular named them semina mternitatis, also 
zopyra, i.e. living tires, luminous flashes, concealed Avithin us, 
but which the encounter of the senses makes appear like the 
sparks which the blow makes spring from the steel. And 
the belief is not without reason, that these glitterings indicate 
something divine and eternal which appears especially in the 
necessary truths. Whence another cpiestion arises, whether 
all truths depend upon experience, i.e. upon induction aiid , I ^ 
examples, or whethfir.jthere are som^_jvjiichL-haye- still a ruetl^e^ | ^ 
^foundation. Por if some eveirEs~canbe foreseen prior to any \ ^ 
proof which may have been made of them, it is manifest \ 
that we ourselves contribute something thereto. The senses,.? 
although necessary for all our actual knowledge, are not suffi- . 
•cient to give it all to us, since the senses never give us anything • 
but examples, i.e. particular or individual truths. Now all the ■ 
examples which confirm a general truth, whatever their num- 
ber, do not suffice to establish the universal necessity of that 
same truth, for it does not follow that what has happened will 
happen in the same way. Por example, the Greeks and the 
Eomans, and all the other peoples of the earth known to the 
ancients, have always observed that before the lapse of twenty- 
four hours day changes into night, and night into day. I>ut 
we would be deceived, if Ave believed that the same laAV holds 
good everywhere else; for since then, the contrary has been 
experienced in the region of Nova Zembla. And he would 
still l)e in error Avho believed that, in our climates at least, this 
is a necessary and eternal trutli, which will always endure, 
since we must think that the earth, and the sun even, do not 
necessarily exist, and that there will perhaps be a time when 
this beautiful star, together with its whole system, will not 
longer exist, at least in its present form. Whence it appears-^ 

1 For a very full iioiiiciiclatnre of these prinei)iles, see ITaniilloirs Reid, 
Nofe A.,§ v., Vol. II., I )]). 755-770. 8tli ed., Kdinlnir-li and I-midoii, ISSO. — 'I'h. 



44 LEIBNITZ'S CRITIQUE OF LOCKE 

that necessary truths such as are found in pure mathematics, 
and particularly in arithmetic and in geometry, must have 
principles whose proof does not depend upon examples, nor 
consequently upon the testimony of the senses, although with- 
out the senses it would never have occurred ta us to-think of 
them. This distinction must be carefully made, and was so 
well understood by Euclid, that he often proved by the reason, 
what is sufficiently seen through experience and by sensible 
images. Logic also, together with metaphysics and ethics, one 
of which shapes theology and the other jurisprudence, both 
natural (sciences), are full of such truths, and consequently 
A their proof can come only from internal principles which are 
A7 called innate. It is true that we must not imagine that these 
^^ eternal laws of the reason can be read in the soul as in an open 
book, as the praetor's edict is read upon his album without diffi- 
culty and research; but it is sufficient that they can be discov- 
ered in us by dint of attention, for which the senses furnish 
occasions, and successful experience serves to confirm reason, 
in much the same way as proofs in arithmetic serve for the 
better avoidance of error in calculating when the reasoning 

''is long. Herein, also, human knowledge differs from that 
of the brutes : the brutes are purely empirics and only guide 
themselves by examples ; for, so far as we can judge of them, 
they never attain to the formation of necessary propositions ; 
while men are capable of demonstrative sciences. 'It is also 

/'for this reason that the faculty the brutes have for making 

\ consecutions is something inferior to the reason of man. The 

consecutions of the brutes are merely like those of simple 

/ empirics, who claim that what has sometimes happened will 

V happen again in a case where something strikes them as similar, 

Vwithout being able to judge whether the same reasons hold 
good. This is why it is so easy for men to entrap the brutes, 
and so easy for simple empirics to make mistakes. This is 
why persons who have become skilful through age and experi- 
ence are not exempt (from error) when they depend too much 
upon their past experience, as has happened to many in civil 
and military affairs ; because they do not consider sufficiently 
that the world changes, and that men become more skilful by 
finding a thousand new dexterities, while the deer and hares 
of the present do not become more cunning than those of the 



ON HUMAN UNDERSTANDING 45 

past. The consecutions of the brutes are only a shadow of 
reasoning, i.e. are only connections of the imagination and 
passages from one image to another, because in a new juncture 
which appears similar to the preceding they expect anew that 
connection which they formerly met with, as if things were 
united in fact because their images are united in the memory. 
I It is true that reason also counsels us to expect ordinarily to see 
/that happen in the future which is conformed to a long past 
■experience, but it is not on this account a necessary and infalli- 
; ble truth, and success may cease when least expected, when 
j ,' the reasons change which have sustained it. Therefore the 
/ wisest men do not so commit themselves to it as not to try to 
discover, if possible, something of the reason of this fact in 
order to judge when it is necessary to make exceptions. For_ 
reason is alone capable of establishing sure rules, and supply- 
" ing what is wanting to those which were not such by inserting 
their exceptions ; and of finding at length certain connections 
in the force of necessary consequences, which often furnish 
the means of foreseeing the result without the necessity of 
experiencing the sense-connections of images, to which the 
brutes are reduced, so that that which justifies the internal ' v 
principles of necessary truths also distinguishes man from the 
-\brutes. | 

Perhaps our clever author will not wholly differ from my 
view. For after having employed the whole of his first book 
in rejecting innate intelligence, taken in a certain sense, he , ■ 
nevertheless, at the beginning of the second and in the sequel, | ( ' 
admits tliat ideas, which do not originate in sensation, come , 
i /from /eflecti^i. ' Now reflection is nothing else than attention 
[ to whafTTmus, and the senses do not give us what we already 
\ carry with us. That being so, can it be denied that there is j^ 
nmch that is innate in our mind, since we are innate, so to-i 

(speak, in ourselves? and that there is in us: being, unity, J -^-r- 
substance, duration, change, action, perception, pleasure, ancT 
a thousand other objects of our intellectual ideas ? And these 
objects being immediate to our understanding and always pres- 
ent (although they cannot always be perceived by reason of- 
our distractions and needs), what wonder that we say that these 
ideas with all depending upon them are innate in us ? I have 
made use also of the comparison of a l)l()ck of marble which 



46 LEIBNITZ'S CRITIQUE OF LOCKE 

. has veins, rather than of a block of marble Avholly even, or of 
blank tablets, i.e. of what is called among philosophers a tabula 
rasa, For if the soul resembled these blank tablets, truths 
would be in us as the figure of Hercules is in the marble, when 
the marble is wholly indifferent to the reception of this figure 
or some other. But if there were veins in the block which 
should indicate the figure of Hercules rather than other fig- 
ures, this block would be more determined thereto, and Her- 
cules would be in it as in some sense innate, although it would 
be needful to labor to discover these veins, to clear them by 
polishing, and by cutting away what prevents them from ap- 
pearing. Thus it is that ideas and truths are for us innate, as 
inclinations, dispositions, habits, or natural potentialities, and 
not as actions ; although these potentialities are always accom- 
panied by some actions, often insensible, which correspond to 
them. 

It seems that our clever author claims that there is nothing 
virtual in us, and indeed nothing of which we are not always 
actually conscious ; but he cannot take this rigorously, other- 
,, wise his opinion would be too paradoxical ; since, moreover, 
^^ acquired habits and the stores of our memory are not always 
perceived and do not even always come to our aid at need, 
although we often easily recall them to the mind upon some 
slight occasion which makes us remember them, just as we 
need only the beginning of a song to remember it.^ He limits 
his thesis also in other places, by saying that there is nothing 
^ in us of which we have not at least formerly been conscious. 
But besides the fact that no one can be assured by reason 
alone how far our j)ast apperceptions, which we may have for- 
gotten, may have gone, especially according to the Platonic 
doctrine of reminiscence which, wholly fabulous as it is, is in 
no respect incompatible at least in part with reason wholly 
pure: besides this, I say, why must we acquire all through 
the perception of external things, and nothing be unearthed in 
ourselves ? Is our soul then by itself such a blank that besides 
the images borrowed from without, it is nothing ? This is not 
an opinion (I am sure) that our judicious author could approve. 

1 Erdmaim and Jacques read: "le commencement d'une chanson pour nous 
faire ressouvenir dii reste," i.e. the beginning of a song to remind us of the 
rest. — Tr. 



I 



ON HUMAN UNDERSTANDING 47 

And where do we find tablets that have no variety in them- 
selves ? For we never see a plane perfectly even and uniform. 
Why, then, could we not furnish also ourselves with something 
of thought from our own depths if we should dig therein? • 
Thus I am led to believe that at bottom his opinion upon this 
point is not different from mine, or rather from the common 
view, inasmuch as he recognizes two sources of our knowledge, 
the Senses and Reflection. 

I do not know whether it will be so easy to harmonize 
him with us and with the Cartesians, when he maintains 
that the mind does not always think, and particularly that 
it is without perception when we sleep without dreaming; 
and he objects ^ that since bodies can exist without motion, 
souls can also exist without thought. But here I make 
a somewhat different reply than is customary, for I hold 
that naturally a substance cannot exist without action, and that 
there is indeed never a body without movement. Experience 
already favors me, and you have only to consult the book of 
the distinguished Mr. Boyle against absolute rest, to be con- r 

vinced of it ; but I believe reason favors it also, and this is one ^ 
of the proofs I have for doing away with atoms. ~^ ^ 

Moreover, there are a thousand indications which make us j 
think that there are at every moment an infinite number of ' 
perce2)tlons in us, but without apperception and reflection, i.e. 
changes in the soul itself of which we are not conscious, be- 
cause the impressions are either too slight and too great in.^^^ — 
number, or too even, so that they have nothing sufficiently 
distinguishing them from each other; but joined to others, 
they do not fail to produce their effect and to make themselves 
felt at least confusedly in the mass. Thus it is that habit .-j--- 
makes us take no notice of the motion of a mill or a waterfall ' 
when we have lived quite near it for some time. It is not 
that the motion does not always strike our organs, and that 
something no longer enters into the soul corresponding 
thereto, in virtue of the harmony of the soul and the body, 
but these impressions which are in the soul and the body, be- 
ing destitute of the attractions of novelty, are not strong 
enougli to attract our attention and our nu^mory, attached to-^'^ir- 
oljjects more engrossing. For all att(!ntiou I'equires memory,. 
1 Enlmaiiu and Jacques vvmX : " II (lit que," i.e. He says that. — Tu. 



48 LEIBNITZ'S CRITIQUE OF LOCKE 

and. ofteu when we are not admonishecl, so to speak, and 
warned to take note of some of" our own present perceptions, 
we allow them to pass without reflection, and even without 
being noticed ; but if any one directs our attention to them 
immediately after, and makes us notice, for example, some 
noise which was just heard, we remember it, and are conscious 
of having had at the time some feeling of it. Thus there 
"were perceptions of which we were not conscious at once, con- 
sciousness arising in this case only from the warning after 
some interval, however small it may be. And to judge still 
better of the minute perceptions which we cannot distinguish 
in the crowd, I am Avont to make use of the example of the 
roar or noise of the sea which strikes one when on its shore. 
To understand this noise as it is made, it would be necessary 
to hear the parts which compose this whole, i.e. the noise of 
each w^ave, although each of these little noises makes itself 
known only in the confused collection of all the others, i.e. in 
the roar itself, and would not be noticed if the wave Avhieh 
makes it were alone. For it must be that we are affected a 
little by the motion of this wave, and that we have some per- 
ception of each one of these noises, small as they are ; other- 
wise we would not have that of a hundred thousand waves, 
since a hundred thousand nothings cannot make something. 
One never sleeps so soundly as not to have some feeble and 
confused sensation, and one would never be awakened by the 
greatest noise in the world if he did not have some perception 
of its small beginning ; just as one would never break a rope 
by the greatest effort in the world if it were not stretched 
and lengthened a little by smaller efforts, although the slight 
extension they produce is not apparent. 

These minute perceptions are, then, of greater efficacy in 
■ their results than one supposes. They form I know not what, 
these tastes, these images of the sense-qualities, clear in the 
mass, but confused in the parts, these impressions which sur- 
roiinding bodies make upon us, which involve the infinite, this 
connection which each beiug has with all the rest of the uni- 
verse. We may even say that in consequence of these minute 
perceptions, the present is big with the future and laden with 
the past, that all things conspire (o-uyaTrvota Travra, as Hip- 
pocrates said), and that in the least of substances eyes as 



ON HUMAN UNDERSTANDING 49 

penetrating as those of God could read the Avhole course of 
the things in the universe. 

QuEe sint, quae fu-erint, quse mox futura trahantur.i 

These insensible perceptions indicate also and constitute the 
same individual who is characterized by the traces or expres- 
sions which they conserve of preceding states of this individual, 
in making the connection with his present state ; and they can be 
known by a superior mind, even if this individual himself should 
not be aware of them, i.e. when there would no longer be in him 
the express recollection of them. But they (these perception.s, 
1 say) furnish, indeed, the means of finding again this recollec- 
tion at need by the periodic developments which may some day 
happen. It is for this reason that death can be only a sleep, and 
cannot, indeed, continue, the perceptions ceasing merely to be 
sufficiently distinguished, and being reduced in the animals to a 
state of confusion which suspends consciousness, but which can- 
not last always ; not to speak ^ here of man, who must have in 
this regard great privileges in order to preserve his personality. 
It is also by means of the insensible perceptions that this 
admirable pre-established harmony of the soul and the body, 
and indeed of all the monads or simple substances, is ex- 
plained ; ^ which supplies the place of the unmaintainable 
influence of one upon the others, and which in the judgment 
of the author of the most excellent of dictionaries exalts the 
grandeur of the divine perceptions beyond what has ever been 
conceived. After this I would add little if I should say that 
it is these minute perceptions which (M£imine us in many 
junctures without being thought of, and which deceive the 
vulgar by the appearance of an indifference of equilibrium, as 
if we were entirely indifferent whether we turned (for ex- 
ample) to the right or to the left. It is not needful also that 
I notice here, as I have done in the book itself, that they 
cause that uneasiness which I show to consist in something 
which differs from pain only as the small from the great, and 
which, however, often constitutes our desire and even our 

1 Erdmami reads: quae mox, etc. ; Jacques: qvx mox ventura trahanfiir. 
Gerliardt's reading: " que " is evidently an error. — Tr. 

'■' Erdmaiiu and Jacques omit: "pour ne parler icy de I'liomme qui doit 
avoir cu cela des grands privileges pour <i;arder sa personalite-." — Tu. 

8 Erdmann and Jac(jU(;s rimd " j'cxpliciue," I cxi)lain. — Tr. 
E 



50 LEIBNITZ'S CRITIQUE OF LOCKE 

pleasure by giving to it an exciting flavor. It is also ' the 
insensible parts of our sensible percepjtions, which produce 
a relation between the perceptions of colors, heat, and other 
sensible (qualities, and between the motions in bodies which 
correspond to them ; while the Cartesians together with 
our author, penetrating as he is, conceive the perceptions 
which we have of these qualities as arbitrary, i.e. as if God 
had given them to the soul according to his good pleasure, 
without any regard to any essential relation between these 
perceptions and their objects: a view which surprises me 
and which appears to me little vv^orthy of the wisdom of 
the Author of things, who does nothing without harmony and 
without reason. 

. - In a word, the insensible perceptions are as eminently use- 
ful in Pneumatology ^ as are the insensible corpuscles in 
Physics, and it is equally unreasonable to reject the one or 
the other under the pretext that they are out of reach of our 
senses. Nothing is accomplished all at once, and it is one of 
my great maxims, and one of the most verified, that nature 
makes no leaps : a maxim which I called the Law of Continuity, 
when I spoke of it in the first " Xouvelles de la Republique 
des Lettres," ^ and the use of this law is very considerable in 
Physics. This law declares that we pass always from the small 
to the great, and the reverse, through the medium, in degree as 
in parts, and that motion never springs immediately from rest, 
nor is reduced thereto save by a smaller motion, as one never 
completes the survey of any line or length until he has com- 
pleted a smaller line, although hitherto those who have set 
forth the laws of motion have not observed this law, believing 
that a body can receive in a moment a motion contrary to the 
preceding. And all this makes one indeed think that the 

1 ErdmaTin and Jacques read : " Ce sont les memes parties insensibles," etc., 
It is tlie same insensible parts, etc. — Tr. 

2 I.e. Psyeliolouy. Cf. Hamilton's Reid, 8th ed., Vol. I., p. 217 a, and note. 
— Tr. 

3 A literary journal published by Pierre Bayle at Amsterdam, 1084-1687 ; 
afterwards continued, at Bayle's i-equest, by Basna^e, under the title " Histoire 
de ouvraffes des Savants," 1087-1709. Leibnitz published in this journal in 
July, 1098, his Edairci.'fsejnent de.'i difficnites que M. Rai/le a tronvees dans le 
nysteme nouveau de I'union de I'ame et du corps. Gerhardt, Vol. 4, pp. 517- 
524; Erdmann, pp. 150-154; Jacques, Vol. 1, pp. 481-187. Translation, Appen- 
dix, pp. 706-712.— Tr. 



ON HUMAN UNDERSTANDING 51 

noticeable jnrceptions also arise by degrees from those which 
are too minute to be observed. To thiuk otherwise, is to have 
little knowTedge of the immense subtilty of things which 
always and everywhere surrounds an actual infinite. "^ 

I have also noticed that in virtue of these insensible varia- ' 
tions, two individual things cannot be perfectly alike, and ; 
that they must always differ more than numero : a fact which '. 
destroys the blank tablets of the soul, a soul without thought, ij 
a substance without action, a vacuum in space, atoms and even 
particles not actually divided in matter, absolute rest, entire 
uniformity in one portion of time, place, or matter, perfect 
globes of the second element, born of cubes perfect and orig- 
inal, and a thousand other fictions of philosophers which arise 
from their incomplete notions, and which the nature of things 
does not allow, and which our ignorance and the little atten- ^" 
tion we give to the insensible let pass, but which cannot be 
made tolerable unless they are limited to the abstractions of 
the mind which protests that it does not deny what it puts 
aside, and thinks should not enter into any present considera- 
tion. Otherwise if it were very well understood, viz. : that 
things of which we are not conscious are neither in the soul 
nor the body, we should be lacking in philosophy as in politics, 
in neglecting to (tiKpov, the insensible progressions, while an 
abstraction is not an error, provided we know what it is that 
we feign therein. Just as the mathematicians employ it when 
they speak of the perfect lines which they propose to us, of 
uniform motions and of other regulated effects, although matter 
{i.e. the medley of the effects of the surrounding infinite) always 
makes some exception. It is for the sake of distinguishing the 
considerations and of reducing so far as we may do so the effects 
to reasons, and of foreseeing some of their consequences, that 
we proceed tlius. For the more we are careful to neglect no 
consideration that we can regulate, the more practice corre- 
sponds to theory. But it belongs only to the supreme Reason, 
whom nothing escapes, distinctly to comprehend all the infinite 
and to see all the reasons and all the consequences. All that 
we can do iii regard to_infinit(;s is to know them confusedly,- 
andTo know at least distinctly that they are such ; otherwise 
we judge very wrongly of the beauty and the grandeur of the 
universe ; so also we could not have a sound ]*hysics explaining 



52 LEIBNITZ'S CRITIQUE OF LOCKE 

the nature of bodies in general, and still less a proper Pncuma- 
tology comprising the knowledge of God, of souls, and of simple 
substances in general. 

This knowledge of insensible perceptions serves also to 
explain why and how two souls, human or otherwise,^ of one 
and the same species never come forth perfectly alike from 
the hands of the Creator and have always each its original 
relation to the points of view which it will have in the uni- 
verse. But this it is which already follows from the remarks 
I have made about two individuals, viz. : that their difference 
is always more than numerical. There is, moreover, another 
point of importance, in respect to which I am obliged to devi- 
ate not only from the opinions of our author, but also from 
those of the majority of modern philosophers : I believe with 
the majority of the ancients that all genii,^ all souls, all simple 
created substances, are always joined to a body, and that there 
are never souls entirely separated. I have a x)'>'iori reasons for 
my view ; but the doctrine will be found to have this advan- 
tage, that it resolves all the philosoj)hical difficulties as to the 
condition of souls, their perpetual conservation, their immor- 
tality, and their operation. The difference between one of 
their states and another, never being and never having been 
other than that of more sensible to less sensible, of more 
perfect to less perfect, or the reverse, this doctrine renders 
their past or future state as explicable as that of the present. 
One feels sufficiently, however little reflection he makes, that 
this is rational, and that a leap from one state to another 
infinitely different could not be natural. I am astonished 
that by leaving the natural without reason, the schoolmen 
have been willing purposely to plunge themselves into very 
great difficulties, and to suj^ply matter for apparent triumphs 
of the strong-minded, all of whose reasons fall at once by this 
explanation of things, in which there is no more difiiculty in 
conceiving the conservation of souls (or rather, according to 
my view, of the animal) than there is in conceiving the change 
of the caterpillar into the butterfly, and the conservation of 
thought in sleep, to which Jesus Christ has divinely well com- 
pared death. I have already said also that sleep could not 

1 Erdmann reads : " on rienx choses," or two things. — Tr. 

2 I.e. Angels and arfhangels. — Tb. 



ON HUMAN UNDERSTANDING 53 

last always, and it will last least or almost not at all iii the 
case of rational souls who are always destined to preserve the 
personality which has been given them in the City of God, 
and consequently remembrance : and this in order to be more 
susceptible of chastisements and recompenses. And I add 
further that in general no derangement of the visible organs 
is capable of throwing things into entire confusion in the 
animal or of destroying all the organs and depriving the soul 
of all its organic body and of the ineffaceable remains of all 
preceding traces. But the ease with which the ancient doc- 
trine of subtile bodies connected with the angels (which was 
confounded with the corporeality of the angels themselves) 
has been abandoned, and the introduction of pretended sepa- 
rate intelligences in creatures (to which those who make the 
heavens of Aristotle revolve have contributed much), and 
finally the poorly understood view into which we have fallen, 
that the souls of brutes could not be preserved without falling 
into metempsychosis, and^ without conducting them from body 
to body, and the perplexity into which men have fallen by 
their ignorance of what to do with them, have caused us, in 
my opinion, to neglect the natural explanation of the conserva- 
tion of the soul. This has done much harm to natural relig- 
ion, and has caused many to believe that our immortality 
was only a miraculous grace of God, of which also our cele- 
brated author speaks with some hesitation, as I shall presently 
remark. But it would be well had all those who are of this 
opinion spoken as wisely and in as good faith as he, for it is to 
be feared that many who speak of immortality as a grace do 
so only to keep up appearances, and resemble at bottom these 
Averroists and some bad Quietists who picture to themselves 
an absorption and the reunion of the soul with the ocean 
of divinity : a notion whose impossibility my system alone 
perhaps evinces. 

It seems also that we differ further in regard to matter, in 
that the author thinks that a vacuum is necessary to motion, 
because he thinks that the minute parts of matter are rigid. 
And I admit that if matter were composed of such ])arts, 

^ Gerhardt's text is: "et sans les promener de corps en forps, et I'embar- 
ras oil Van a este on nc saeliant ce qii'on en dovoit faire." Erduiaiin and 
Jacques omit the elause. — 'I"i:. 



64 LEIBNITZ'S CRITIQUE OF LOCKE 

motiou iu a plenum would be impossible, as if a room were 
lull of a quantity of little pebbles without there being the 
least empty space. But this supposition, for which there 
appears also to be no reason, is not admissible, although this 
learned author goes as far as to believe that rigidity or cohe- 
sion of the minute parts makes the essence of the body. It is 
necessary rather to conceive space as full of a matter origi- 
nally fluid, susceptible of all the divisions, and even actually 
subject to divisions and subdivisions to infinity, but with 
this difference, however, that it is divisible and divided un- 
equally in different parts on account of the motions which 
more or less concur there. This it is which causes matter to 
have everywhere a degree of rigidity as well as of fluidity, and 
no body to be hard or fluid in the highest degree, i.e. no atom 
to be found of an insurmountable hardness nor any mass 
entirely indifferent to division. The order, also, of nature, and 
particularly the law of continuity, destroy equally the one and 
the other. 

I have also shown that cohesion, which b}' itself -yvould not 
be the effect of impulse or of motion, would cause a traction, 
taken strictly. For if there were a body originally rigid, — for 
example, an Epicurean atom, — which should have a part pro- 
jecting like a hook (since we can imagine atoms of all sorts of 
shapes), this hook pushed would draw with it the rest of this 
atom ; i.e. the part which is not pushed, and which does not 
fall in the line of the impulsion. Our learned author, how- 
ever, is for himself opposed to these philosophic tractions, 
such as were formerly attributed to the abhorrence of a 
vacuum, and he reduces them to impulsions, maintaining with 
the moderns that one part of matter works immediately upon 
another only by pushing it by contact, in which I think they 
are right, because otherwise there is nothing intelligible in the 
oj^eration. 

I must not, however, conceal the fact that I have noticed a 
sort of retraction by our excellent author on this subject, 
whose modest sincerity I cannot forbear praising in this 
respect as much as I have admired on other occasions his 
penetrating genius. It is in his reply to the second letter of 
the late Bishop of Worcester,^ printed in 1699, p. 408, where, 

1 Edward Stilliugfleet, 1635-1(;*)!»: Bishop ol Worcester, 1G8'.)-I(;'.)ii. — Tr. 



ON HUMAN UNDERSTANDING 55 

in order to justify the view which he had maintained against 
this wise prelate, viz. : that matter might tliink, he says among 
other things : " / admit that I said (Essay on Understanding, 
Book II. chap. 8, § 11) that body acts by imimlse and not 
otherwise. This also was my vieio ichen I wrote it, and even now 
I cannot conceive its action in any other way. But since then I 
have been convinced by the judicious Mr. Newton's incomjjarable 
book that there is too much loresumption in tvishing to limit the 
poiver of God by our limited coyxceptions. The gravitation of 
matter towards matter in ways inconceivable to me., is not only a 
demonstration that God, ivhen it seems to him good, can j^ut into 
bodies poicers and modes of acting lohich are beyond what can be 
derived from our idea of body or explained by tohat loe know of 
matter; bid it is furthermore an incontestable instance that he has 
really done so. I shall therefore take care to correct this passage 
in the next edition of my book.''' ^ I find that in the French 
version of this book, made undoubtedly from the latest edi- 
tions, the matter has been put thus in this % 11 : It is evident, 
at least so far as we can conceive it, that it is by imptdse and 
not otherwise that bodies act on each other; for it is impossible 
for us to understand hoiv the body can act upon what it does not 
touch, which is the same as to imagine that it can act ivhere it 
is not. 

I can only praise this modest piety of our celebrated author, 
who recognizes that God can do more than we can understand, 
and that thus there may be inconceivable mysteries in the 
articles of faith ; but I should not wish to be obliged to recur 
to the miracle in the ordinary course of nature and to admit 
powers and operations absolutely inexplicable. Otherwise too 
much license will be given poor philosophers, under coven- of 
what God can do, and by admitting these centripetal virtues or 
these immediate attractions from afar without being able to 
make them intelligible, I see nothing to hinder our Seliolastics 
from saying that everything is done simply by their facnilties 
and from maintaining their intentional species wliich proceed 

I I have retranslated the passage from the Froneh version, as jjiven by Ger- 
hardt. For the original, cf. Locke, Philofi. Works (Holm's (^d.), Vol. II., p. '.M^. 
The entire letter is fonnd in Loeke's Works, Vol. I., pp. 578-774; tliis particu- 
lar passage, p. 754. Edition of 4 vols., 4to. 7th ed., 17(>8. Printed for II. Wood- 
fall, A. Millai-, and otliers. — Tr. 



56 LEIBNITZ'S CRITIQUE OF LOCKE 

from objects even to us aud fiud means of entering even into 
our souls. If that is so, 

Umuia jam tient, fieri quae posse negabam. 

So that it seems to me that our author, quite judicious as he 
is, goes here a little too much from one extreme to the other. 
He makes a difficulty in regard to the operations of souls when 
the question is only of admitting what is not soisible, and 
behold he gives to bodies what is not even intelligible ; granting 
them powers and actions which surpass in my view all that a 
created spirit can do and understand, since he grants them 
attraction, and that even at great distances without limiting 
them to any sphere of activity, and this in order to maintain a 
view which does not appear less inexplicable, viz. : the possi- 
bilit}' of the thought of matter in the natural order. 

The question which he discusses with the celebrated Prelate 
who attacked him, is, wliether matter can think, and as it is an 
important point even for the present work, I cannot refrain 
from entering upon it a little and from taking note of their 
controversy. I will give the substance of their discussion 
upon this subject, and take the liberty of saying what I think 
of it. The late Bishop of Worcester, fearing (but in my 
opinion without good reason) lest our author's doctrine of ideas 
might be liable to certain abuses prejudicial to the Christian 
faith, undertook to examine some points in it in his "Vindication 
of the Doctrine of the Trinity " ; ^ and having rendered justice 
to this excellent writer, by recognizing that he thinks the exist- 
ence of spirit as certain as that of body, although one of these 
substances is as little known as the other, he asks (p. 241 sq.) 
how reflection can assure us of the existence of spirit, if God 
can give to matter the power of thought according to the view 
of our author, Book IV., chap. 3, since thus the way of ideas 
which must serve to discern - what may suit the soul or the 
body, would become useless ; while he had said in Book II. of 
the Essay on Understanding, chap. 23, §§ 15, 27, 28, that the 
operations of the soul furnish us the idea of mind and the 

1 Published in tlie autumn of 1696. Cf. Alexander Campbell Fraser, Locke, 
pp. 245-2-KJ (Philosophical Classics), Edinburgh: Wm. Blackwood and Sous, 
1890. — Tr. 

2 Gerhardt reads: " disceruer " ; Erdmann and Jacques: "discuter," to 
discuss, debate, argue. — Tr. 



I 



ON HUMAN UNDERSTxVNDING 57 

understanding, and the Avill renders this idea as intelligible to 
us as the nature of body is rendered intelligible to us by solid- 
ity and impulse. This is how our author replies in his first 
letter (p. 65 sq.) : " I believe I have proved that there is a spirit- 
ual substance in us, for toe experience in ourselves thought. Now 
this action or this mode cannot be the object of the idea of a thing 
subsisting by itself, and consequently this mode needs a suptport, a 
subject, in -which it may inhere, and the idea of this support forms 
what ice call substance. . . . For since the general idea of sub- 
stance is everywhere the same, it follows that the modijication, 
which is called thought or power of thinking, being joined to it, 
there results a mind without the necessity of considering what 
other modijication it has besides; i.e. ivhether it has solidity or 
not. And, on the other hand, the substance which has the modifi- 
cation called solidity ivill be matter, whether thought is joined to it 
or not. But if by a spiiritual substance you mean an immaterial 
substance, I admit that I have not proved that there is one in us, 
and that it cannot be demonstrably proved on my prrincipjles. Al- 
though tvhat I have said on the systeins of matter (Book IV., 
chap. 10, § 16) in j)roving that God is immaterial, renders it in 
the highest degree probcd>le, that the substance ichich thinks in us 
is immaterial. . . . However, I have shoivn [the author adds, 
p. 68] that the great ends of religion and of morals are assured 
by the immortality of the soid, icithout the need of supposing its 
immateriality.^' ^ 

The learned Bishop in his reply to this letter, in order to 
make it evident that our author held another view, when he 
wrote the second book of the Essay, quotes, p. 51, this passage 
(taken from the same book, chap. 23, § 15), where it is said, that 
by the simj)l€ ideas which we have deduced from the operations of 
our mind, we can form the complex idea of a mind. And that 
putting together the ideas of thought, of perception, of liberty, and 
of power to move our body, we have as clear a notion of immate- 
ricd substances as of mcderial. He quotes still other passages 
to shoAv that the author opposes mind to body. And he says 
(p. 54) that the ends of religion and of morals are the better 

1 1 have retranslated the passage from tlie French version as given by Ger- 
hardt. For the orisinal, of. Lot^ke, Philos. Works (Bohn's ed.), Vol. 11., 
p. 387. The entire letter is found in Locke's Works, Vol. I., pp. 45«-r)17 ; tliis 
particular passage, p. 477. Edition of 4 vols., 4to. 7th ed., 17()8. Printed for 
H. Woodfall, A. Millar, and others. — Tr. 



58 LEIBNITZ'S CRITIQUE OF LOCKE 

assured by proving that the soul is immortal by its nature, i.e. 
immaterial. He quotes also (p. 7U) this passage, that the ideas 
ive have of 2'>o,rticxdar and distinct kinds of substances are nothing 
else than different combinations of simple ideas ;^ and that thus 
the author believed that the idea of thinking and of willing 
gave another substance different from that which the idea of 
solidity and of impulse gives, and that (§ 17) he remarks that 
these ideas constitute the body as opposed to mind. 

The Bishop of Worcester might add that from the fact that 
the general idea of substance is in the body and in the mind, 
it does not follow that their differences are modifications of one 
and the same thing, as our author has just said in the jjart of 
his first letter which I have quoted. It is necessary carefully 
to distinguish between modifications and attributes. The 
faculties of having perception and of acting, extension, solid- 
ity, are attributes or perpetual and principal predicates ; but 
thought, impetuosity, figures, movements, are modifications of 
these attributes. Furthermore, we must distinguish between 
physical (or, rather, real) genus and logical or ideal genus. 
Things which are of the same physical genus, or which are 
homogeneous, are of the same matter, so to speak, and may 
often be changed the one into the other by the change of mod- 
ification, as circles and squares. But two heterogeneous things 
may have a common logical genus, and then their differences 
are not simple accidental modifications of one and the same 
subject, or of one and the same metaphysical or physical mat- 
ter. Thus time and space are very heterogeneous things, and 
we should do wrong to imagine I know not what real common 
subject which had only the continuous quantity in general, 
and whose modifications should cause the rise of time and 
space.- Some one will perhaps laugh at these distinctions of 
the philosophers of two genera, the one merely logical, the 
other real ; and of two matters, the one physical, viz. : that of 
bodies, the other metaphysical only or general ; as if some one 
said that two parts of space are of one and the same matter, 
or that two hours are likewise among themselves of one and 

1 Locke, Phihis. Works (Bohirs ecL), Vol. 1, p. 426, chap. 23. § (>. — Tr. 

- Erdmaiiii and Jacques add : " Cepeudant leur genre logique comniun est la 
quantite continue," i.e. Nevertheless their common logical genus is the con- 
tinuous quantity. — Tr. 



ON HUMAN UNDERSTANDING 59 

the same matter. Nevertheless, these distinctions are not dis- 
tinctions of terms merely, but of things themselves, and seem 
to come in here very opportunely, where their confusion has 
given rise to a false conclusion. These two genera have a 
common notion, and that of the real genus is common to the 
two matters, so that their genealogy will be as follows : — 

r LogicMl merely, varied by simple differences. 
\ r Metaphysical only, where 

renus 1 ^^^^^ -vvhose differences are modi- I there is homogeneity. 

[ Jications, i.e. Matter. j Physical, where there is a 

[ solid homogeneous mass. 

I have not seen the second letter of the author to the 
Bishop, and the reply which this prelate makes to it scarcely 
touches the point relating to the thinking of matter. But the 
reply of our author to this second ansAver returns to it. God 
(says he, nearly in these words, p. 397) adds to the essence of 
matter the qualities and 2^€'>'f€ctions which p/ease /im, simple 
movement in some parts, but in plants, vegetation, and in ani- 
mals, sentiency. Those who agree up to this x)oint, cry out as 
soon as we go a step farther, and say that God can give to matter 
thought, reason, icill, as if this destroyed the essence of matter. 
But to prove it, they allege that thought or reason is not included 
in the essence of matter, a point of no consequence, since move- 
ment and life are not included therein either. They assert, also, 
that we cannot conceive of matter as thinking ; hut our conception 
is not the measure of God's power. ^ After this he cites the ex- 
ample of the attraction of matter (p. 99, but especially p. 408), 
where he speaks of the gravitation of matter towards matter, 
attributed to Mr. Newton (in the terms which I have quoted 
above), admitting that we can never conceive the manner of it. 
This is in reality to return to the occult, or, what is more, in- 
explicable qualities. He adds (p. 401) that nothing is more 
calculated to favor the sceptics than to deny what we do not 
understand ; and (p. 402) that wc do not conceive even how the 
soul thinks. He will have it (p. 403) that, since the two sub- 

1 For tlie ori-inal, cf. Locke, Phih>!<. Worls (Bolm's ed.), Vol. 2, i)|). .".iiO, ;'.!»1. 
The entire letter is found in Locke's Works, Vol.1, pp. .578-774; tlii.s particu- 
lar passage, pp. 74<t, 7.50. Edition of 4 vols., 4to. 7th ed., 1708. Printed for 
H. Woodfall, A. Miller, and others. — Tk. 



60 LEIBNITZ'S ClUTIQUE OF LOCKE 



stances, material and immaterial, are capable of being conceived 
in their naked essence -witliout any activity, it depends upon 
God to give to each the power of thought. And he wishes to 
take advantage of the admission of his opponent, who had 
granted sentiency to the brutes, but wlio would not grant them 
any immaterial substance. He claims that liberty, conscious- 
ness (p. 408), and the power of abstract thought (p. 409) can 
be bestowed upon matter, not as matter, but as enriched by a 
divine power. Finally, he quotes (p. 434) the remark of a 
traveller as eminent and judicious as M. de la Loubere,^ that 
the pagans of the East acknowledge the immortality of the 
soul without being able to comprehend its immateriality. 

On all this I would remark, before coming to the explana- 
tion of my view, that it is certain that matter is as little capa- 
ble of mechanically producing feeling, as of producing reason, 
as our author admits ; that in truth I acknowledge that it is 
not permissible to deny what we do not understand, but I add 
that we are right in denying (at least in the natural order) 
what is absolutely neither intelligible nor explicable. I main- 
tain, also, that substances (material or immaterial) cannot be 
conceived in their naked essence without any activity ; that 
activity belongs to the essence of substance in general ; that, 
finally, the conception of creatures is not the measure of God's 
power, but that their conceptivity, or power of conception, is 
the measure of nature's power; all this is in harmony with 
the natural order, being capable of being conceived or under- 
stood by some creature. 

Those who understand my system will think that I cannot 
wholly agree with the one or the other of these two excellent 
authors, whose discussion, however, is very instructive. But 
to explain myself distinctly, it is necessary before all things 
to consider that the modifications which may belong naturally 
or without miracle to a subject must come to it from the limi- 
tations or variations of a real genus, or of a constant and abso- 
lute original nature. For it is thus that Philosophers dis- 

1 La Loubere, Simon de, 1642-1729. Sent by Louis XIV. in 1(587 to Siam, 
to estaljlish diplomatic and commercial relations between that kingdom and 
France. While there he collected a large amount of exact and interesting 
information concerning the country, its history, customs, religion, etc., which, 
on his return, he published in his Du royaume de Siaiyi, Paris, 1691; English 
translation, London, 1693. — Tr. 



1 



ON HUMAN UNDERSTANDING 61 

tinguisli the modes of an absolute being from that being itself ; 
as it is known that size, figure, and movement are manifestly 
limitations and variations of corporeal nature. For it is clear 
how a limited extension gives figures, and that the change 
which is made in it is nothing but motion. And whenever 
we find any quality in a subject, we must believe that if we 
understood the nature of this subject and of this quality, we 
should conceive how this quality can result therefrom. Thus 
in the order of nature (miracles aside) it is not optional with 
God to give to substances indifferently such or such qualities, 
and he will never give to them any, save those which will be 
natural to them, i.e. which can be derived from their nature as 
explicable modifications. Thus it may be asserted that matter 
will not naturally possess the attraction mentioned above, and 
will not proceed of itself in a curved line, because it is impossi- 
ble to conceive how this takes place there, i.e. to explain it 
mechanically, while that which is natural must be capable of 
becoming distinctly conceivable if we were admitted into the 
secrets of things. This distinction between what is natural 
and explicable and what is inexplicable and miraculous 
removes all the difficulties, and by rejecting it, we should 
maintain something worse than the occult qualities ; and in so 
doing would renounce philosophy and reason, by opening 
retreats for ignorance and idleness, though a dead system, 
which admits not only that there are qualities which we do not 
understand, of which there are only too many, but also that 
there are some which the greatest mind, if God gave him every 
possible opening, could not comprehend, i.e. which would be 
either miraculous or without rhyme and reason ; and also that 
God should work miracles ordinarily would be without rhyme 
and reason, so that this hypothesis would destroy equally our 
philosophy which seeks reasons, and the divine wisdom which 
furnishes them. 

Now as to thought, it is certain, and the author admits it 
more than once, that it could not be an intelligible modifica- 
tion of nature or one which could be comprised therein and 
explained, i.e. that a being who feels and thinks is not a mech- 
anism like a watch or a mill, so that we might conceive sizes, 
figures, and movements, whose mechanical conjunction might 
produce something thinking, and even feeling in a mass in 



62 LEIBNITZ'S CKI'IUirK OF LOCKE 

■which there was nothing of the kind, which Avould cease also 
in the same manner npon the derangement of this mechanism. 
It is not then a natural thing for matter to feel and think, and 
this can happen within it only in two ways, of which one will 
be that God should unite with it a substance to which thought 
is natural, and the other that God by a miracle should put 
thought therein. In this, then, I am wholly of the opinion of 
the Cartesians, except that I extend it even to the brutes, 
and that I believe they have sentiency and (properly speak- 
ing) immaterial souls, and are as imperishable as the atoms of 
Democritus or Gassendi, while the Cartesians, perplexed with- 
out reason by the souls of brutes, and not knowing what they 
are to do with them if they are preserved (for want of having 
thought of the conservation of the same animal reduced to 
miniature), have been compelled to refuse even sentiency to the 
animals against all appearances and contrary to the judgment 
of the human race. Biit if any one should say that God at 
least may add the faculty of thinking to the prepared mechan- 
ism, I should reply that if this were done, and if God added 
this faculty to matter without j)utting therein at the same 
time a substance which was the subject of inhesion of this 
same faculty (as I conceive it), i.e. without adding thereto an 
immaterial soul, it would be necessary that matter should be 
miraculously exalted in order to receive a power of which it is 
naturally incapable ; as some scholastics ^ claim that God ex- 
alts fire even to the point of giving it the force to burn imme- 
diately spirits separated from matter, a thing which would be 
a miracle, pure and simple. And it is enough that it cannot 
be maintained that matter thinks without putting into it an 
imperishable soul, or a miracle, and that thus the immortality 
of our souls follows from what is natui-al, since their extinc- 
tion can be maintained only by a miracle, whether by exalting 
matter or by annihilating the soul. For we know well that 
God's power can make our souls mortal, wholly immaterial 
(or immortal by nature alone) as they may be, since he can 
annihilate them. 

Xow this truth of the immateriality of the soul is undoubt- 

1 Erdmann and .Jacques read : " Quelques sclinlnstiques ont pretendu quelqne 
chose d'approchant savoir," i.e. Some scholastics have claimed something 
like this : viz. — Tr. 



I 



ON HUMAN UNDERSTANDING 63 

edly of importance. For it is infinitely more advantageous to 
religion and morality, especially in our times (when many 
people hardly respect revelation alone and miracles '), to show 
that souls are immortal by nature, — and that it would be a mir- 
acle if they were not, — than to maintain that our souls ought 
naturally to die, but that it is in virtue of a miraculous grace 
grounded in the promise of God alone that they do not die. 
Also for a long time it has been known that those who have 
desired to destroy natural religion and to reduce all to revealed 
religion, as if reason tauglit us nothing regarding it, have been 
looked upon with suspicion ; and not always without reason. 
But our author does not belong to that number. He maintains 
the demonstration of the existence of God, and he attributes 
to the immateriality of the soul a probability in the highest de- 
gree, which could consequently pass for a moral certainty, so 
that I think that, having as much sincerity as j^enetration, he 
could easily accommodate himself to the doctrine which I have 
just set forth, and which is fundamental in every rational phi- 
losophy. For otherwise I do not see how one can prevent him- 
self from falling back into the fanatical philosoj^hy,^ such as the 
"Philosophia Mosaica" of Fludd,'' which saves all phenomena by 
attributing them to God immediately and by miracle ; or into 
the barbaric philosophy like that of certain philosophers and 
physicians of the past, which still manifested the barbarity of 
their age, and which to-day is with reason despised, who saved 
appearances by forging purposely occult qualities or faculties 
which they imagined to be like little demons or goblins capa- 
ble of producing without ceremony what is demanded, just as 
if watches marked the hours by a certain horodeictic faculty 
without needing wheels, or as if mills ground the grain by a 
fractive faculty without needing anything resembling mill- 
stones. As to the difficulty that many people have had in 
conceiving an immaterial substance, it will easily cease (at 
least in good part) if they will not demand substances sepa- 
rated from matter, as in fact I do not believe there ever are any 
naturally among creatures. 

1 Erdmann and .Jacques omit this clause. — Tit. 

2 Erflmann and .Tacqucs road : " la philosophie ou fanatiquc," i.e. pliilosopliy 
\ or fanaticism. — Tr. 

3 R()l)(!rt P'liidd (ir)74-lfi.'')7), an Ensrlisli physician and mystical philosopher. 
The Philosrqihia Mosaica was publislicd at Gouda in KilJH. — Tr. 



NEW ESSAYS ON HUMAN UNDERSTANDING 



Book I. — Innate Ideas 
CHAPTER V 

ARE THERE IJ7XATE PRINCIPLES IN THE MIND OF MAN ? 

Philalethes. Having recrossed the sea after finishing my 
business in England, I thought at once of pajdng you a visit, 
sir, in order to cultivate our former friendship, and to con- 
verse upon matters which lie close to our hearts, and upon 
which I believe I have acquired some new light during my 
long stay in London. When we were living formerly quite 
near each other at Amsterdam, we both took much pleasure 
in making researches into the principles and means of pene- 
trating into the heart of things. Although our opinions often 
differed, this diversity increased our satisfaction, when, in our 
conference together, notwithstanding the contrariety which 
sometimes existed, there mingled nothing disagreeable. You 
were for Descartes ^ and for the opinions of the celebrated 
author- of "The Search after Truth," and I found the opinions 
of Gassendi,- cleared up by Bernier, easier and more natural. 
Xow I feel myself greatly strengthened by the excellent work 
which an illustrious Englishman, with whom I have the honor 
of a particular acquaintance, has since published, and which 
has several times been reprinted in England, under the modest 

1 Book I. of Locke's Essay has four chapters, of which chap. 1 is introduc- 
tory. Chap. 1 of Leibnitz corresponds to cliap. 2 of Locke. — Tr. 

2 Rene Descartes, 1596-1650; Nicolas Malebrauclie, 16.38-1715, his chief 
work, Be la Recherche de la Verite, 1674; Pierre Gassendi, 1592-1655, Ahre[/e 
de la Philosophie de Gassendi, 8 vols., 1678, 2d ed., 7 vols., 1()84, by Fran9ois 
Bernier. — Tr. 

64 



CH. I] ON HUMAN UNDERSTANDING 65 

title of "An Essay concerning Human Understanding." And 
I am delighted that it has appeared lately in Latin and in 
French, in order that it may be more generally useful. I have 
greatly profited by the reading of this work, and indeed from 
the conversation of the author, with whom I have talked 
often in London, and sometimes at Gates, at the house of my 
Lady Masham,^ worthy daughter of the celebrated Cudworth,^ 
a great English philosopher and theologian, author of the 
Intellectual System, from whom she has inherited the spirit 
of meditation and the love for good learning, which appeared 
particularly in the friendship which she kept up with the 
author of the Essay. And, as he had been attacked by some 
clever Doctors, I took pleasure in reading also the defence 
which a very wise and very intelligent young lady made for 
him, besides those which he made for himself. This author 
writes in the spirit of the system of Gassendi, which is at 
bottom that of Democritus ; ^ he is for the vacuum and for 
atoms ; he believes that matter might think ; that there are 
no innate ideas, that our mind is a tabula rasa, and that we do 
not always think; and he appears disposed to approve the 
most of the objections which Gassendi has made ^ to Descartes. 
He has enriched and strengthened this system by a thousand 
beautiful reflections ; and I do not at all doubt that now our 
party will triumph boldly over its adversaries, the Peripa- 
tetics and the Cartesians. This is why, if you have not yet 
read this book, I invite you to do so, and if you have read it, 
I I ask you to give me your opinion of it. 
2\\ ^\Theophilus. I rejoice to see you, on your return after a long 
absence, happy in the conclusion of your important business, 
full of health, steadfast in your friendship for me, and always 
transported with an ardor equal to the search for the most 

1 Tlie correspondence between Leil)nitz and Lady Mashani is yiveu in full 
by Gerhardt, Vol. .'5, pj). .381 ,sg. — Tr. 

2 Ralph Cudworth, 1G17-1688, liis i)rincipal work, The True Intellectual 
System of the Universe, London, l(i7H; Uemocritns, l)orn i)robahly about the 
middle of the fifth century B.C., as h<! says (Dioij. L., IX., 41) lu; was "still 
young when Anaxagoras," 500-428 n.c, "was already old (leo? Kara TTp^rftx'nrjv 
'Ava^ayopav)." . . . "The year of Ills deatli is unknown," Zcllcr, Outlines 
of the n into ry of Greek Philosojihy, pp. 7G, 77, New York: II. Holt & Co., 
1880.— Tr. 

'^ In Vol. 3 of his Opera, of which two editions were jynblisliiMl : by Mont- 
mort, 1G55, G vols, folio, Lyons; by Averanins, 1727, also G vols, folio. — Tr. 
F 



J 



06 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

important truths. I uo less have continued my meditations 
in the same spirit, and I believe I have profited as much as, 
and, not to flatter myself, perhaps more than yourself. In- 
deed, my need tlierein was greater than yours, for you were 
more advanced than I. You were more conversant with spec- 
ulative philosophers, and I was more inclined towards ethics. 
But I have learned more and more how ethics receives strength 
from the solid principles of true philosophy ; therefore I have 
lately studied these principles more diligently, and have begun, 
meditations quite new. So that we shall have the means of 
giving ourselves a reciprocal pleasure of long duration in com- 
municating the one to the other our solutions. But it is nec- 
essary for me to tell you, as a piece of news, that I am no 
longer a Cartesian, and that, nevertheless, I am farther re- 
moved than ever from your Gassendi, whose knowledge and 
merit I, for the rest, recognize. I have been impressed with 
a new system, of which I have read something in the " Jour- 
naux des Savans " of Paris, Leipzig, and Holland, and in the 
marvellous Dictionary of Bayle, article "Eorarius"^; and since 
then I believe I see a new aspect of the interior of things. 
This system appears to unite Plato ^ and Democritus, Aristotle^ 
and Descartes, the scholastics with the moderns, theology and 
ethics with the reason. It seems to take the best from all 
sides, and then it goes much farther than any has yet 
gone. I find in it an intelligible explanation of the union of 
soul and body, of which I had before this despaired. I find 
the true principles of things in the Unities of Substance, which 
this system introduces, and in their harmony pre-established 
by the primitive Substance. I find therein a wonderful sim- 
plicity and uniformity, so that it may be said that this sub- 
stance is everywhere and always the same thing, differing 
only in degrees of perfection. I see now what Plato meant 
when he assumed matter to be an existence imperfect and 
transitory ; what Aristotle meant b}^ his Entelechy ; what that 
promise of another life is which Democritus himself made 
according to Pliny ; how far the Sceptics were right in de- 
claiming against the senses ; how animals are in fact automata 

1 Cf. Gerhardt, Vol. 4, pp. 524-55-1, the article " Rorarius " with Leibnitz's 
remarks. — Tr. 

2 Plato, 427-.>47 B.C. ; Aristotle, 384-^22 B.C. — Te. 



CH. i] ON HUMAN UNDERSTANDING 67 

according to Descartes, and liow they have, nevertheless, souls 
and feeling according to the opinion of mankind ; how it is 
necessary to explain rationally those who have lodged life and 
perception in all things, as Cardan,^ Campanella,^ and, better 
than they, the late Countess of Connaway, a Platonist, and our 
friend, the late M. FranQois Mercure van Helmont '^ (although 
elsewhere bristling with unintelligible paradoxes), Avith his 
friend, the late Mr. Henry More.- How the laws of nature (a 
good part of which were unknown before this system) have 
their origin in principles superior to matter, and how, never- 
theless, everything takes place mechanically in matter, in 
which respect the spiritualizing authors I just named have 
failed with their Arcluei,^ and even the Cartesians, in believ- 

1 Girolamo Card;uio, 1501-157G ; Tommaso Campauella, 1568-1639 ; c/. Erd- 
maiiii, Grundriss d. Geseh. d. Philos., 3d ed., Vol. 1, §§ 242, 246, Berlin: Wil- 
heliii Hertz, 1878, aud the English translation of the same, London: Swau 
Sonnenscheiu & Co., 1889; also the articles "Cardan" and "Campanella" in 
the Encyclopxdia Britanntra, 9th ed. — Tr. 

2 Van Helmont, 1618-1(>98: Henry More, 1614-lf)87. — Tr. 

3 Archsmis, i. Modern Latin, from the Greek apxaios, apx^, that which is at 
the beginning, source, origin, a first principle. Littre' defines the term thus : 
" An-he'e. Terme de physiologic ancieune. Principe immaterial diffe'rent de 
I'ame intelligent et qu'on supposait presider a tons les phenomenes de la 
vie materielle." I.e. "A term of ancient physiology. An immaterial princi- 
ple different from tlie intelligent soul, and which is supposed to preside over 
all tlie phenomena of the material life." The Century Dictionary gives the 
following exposition and illustration: "In the i^hilosophy of Paracelsus and 
other spagyrics, mysticSj and theosophists, a spirit or invisible man or animal 
of ethereal substance, the counterpart of the visible body, within whii^h it 
resides, and to which it imparts life, strength, and the power of assimilating 
food. The word is said to have been used by Basil Valentine, a German 
clicniist of the fifteenth century, to denote the solar heat as the source of the 
life of plants. Paracelsus uses it with the above; meaning. It is frequent in 
tli(; writings of Van Helmont, who explains it as a material pre-existence of the 
human or animal form in posse. He regards the archseus as a fluid, i.e. as a 
semi-material substance like air, and seems to consider it a chemical constituent 
of the blood. Paracelsus has particularly made use of the hypothesis of the 
archjEus to explain the assimilation of food. This function of tlie arcliams 
became prominent in medicine. Van Helmont calls it the doorkeeper of the 
slomacli (Jiiiiiliir stomachi). Tliere are further divarications of meaning. 
Al.so spelled Archeus." 

" As for the many pretended intricacies in the instance of the cfformation 
of Wasps out of the Carcase of a Horse, I say, the Archel tliat formed them 
are no parts of the; Horse's Soul that is deail, hut several distinct Arr.hei that 
do as naturally joyn with the matter of his body, .so putrifled and prepared, 
as tlie Crowes come to eat his flesh." — Dr. H. Mohk, Antidote a(/uinst 
Athe'iHin, app. xi. ^ 

Cf. Leibnitz: Considerations sur le Principe de Vie et sur les Natures Plas- 



68 LEIBNITZ'S CRITIQUE OF LOCKE [uic. i 

ing that immaterial substances altered if not the force, at 
least the direction or determination, of the motions of bodies, 
whereas the soul and the body retain perfectly each its own 
laws, according to the new system, and yet one obeys the 
other as much as is necessary. In fine, it is since I have med- 

^ itated upon this system that I have found out how the souls 
/ of beasts and their sensations are in no sense prejudicial to 

1/ the immortality of human souls, or, rather, how nothing is 
more suited to establish our natural immortality than to con- 
ceive that all sou.ls are imperishable {morte carent animce), 
without, however, the fear of metempsychoses, since not only 
the souls, but further, the animals endure and will endure liv- 
ing, feeling, acting; it is everywhere as here, and always and 
•everywhere as with us, according to what I have already said 
to you, except that the conditions of animals are more or less 
perfect and developed, without there ever being a need of 
souls wholly separate, while we nevertheless have always 
sjDirits as pure as possible, notwithstanding our (physical) 
organs, which cannot disturb by any influence the laws of our 
(spiritual) spontaneity. I find the vacuum and atoms excluded 
in quite another way than by the sophism of the Cartesians, 
grounded in the pretended coincidence of the idea of body and 
extension. _I see all things determined and adorned beyond 
anything hitherto conceived; matter everywhere organic, no 
sterile, neglected vacuum, nothing too uniform, everything 
varied, but with order; and, what passes imagination, the 
entire universe in epitome, but with a different aspect in each 
of its parts, and likewise in each of its unities of substance. 
Besides this new analysis of things, I have a better compre- 
hension of that of notions or ideas, and of truths. I under- 
stand what a true, clear, distinct, adequate idea is, if I dare 
adopt this word. I understand what are primitive truths, and 
true axioms, the distinction between necessary truths and 

tiquespar I'Auteur de V Harmonic Pr^etahlie, published in the " Histoire des 
Ouvrages des Savaus," May, 1705, Gerhardt, Vol. (J, pp. 539-546; Erdmaiin, 
pp. 420-432; translation, Duncan, Philos. Works of Leibnitz, pp. 163-169. See 
also Erdmann, GrundriKs d. Gesrh. d. Philos. 3d ed., Vol. 1, § 241, 7, Vol.2, 
§ 2iX), 12, or theEnijlish tran.slation of the same. Slight additional information 
may be found in the Encydopsedia Britannica, 9th ed., under the article, 
"Medicine," in the part giving an account of Paracelsus and Van Hel- 
mont. — Tr. 



CH. i] ON HUMAN UNDERSTANDING 69 

truths of fact, between the reasoning of men and the consecu- 
tions of animals, which are a shadow of the reasoning of men. 
In short, you 'will be surprised to hear all that I have to say 
to you, and, above all, to understand how much the knowledge 
of the grandeur and of the perfection of God is therein exalted. 
For I cannot conceal from you, from whom I have had nothing 
concealed, how I have been thrilled now with admiration and 
(if we may dare to make use of the term) with love for this 
sovereign source of things and of beauty, having found that 
what this system discovers surpasses everything one has hith- 
erto conceived. You knOw that I had gone a little too far 
formerly, and that I began to lean toward the side of the 
Spinozists,^ who allow God only infinite power, without recog- 
nizing either perfection or wisdom in his case, and regarding 
with contempt the search for final causes, derive everything 
from brute necessity. But these new lights have cured me of 
this ; and since then I sometimes take the name of Theophilus. 
I have read the book of this celebrated Englishman of whom 
you have just spoken. I value it highly, and I have found in 
it some good things. But it seems to me necessary to go 
much farther, and necessary even to turn aside from his views, 
since he has adopted some which limit us more than is neces- 
sary, and lower a little not only the condition of man, but, 
besides, that of the universe. 

Ph. You astonish me in fact with all the marvels which 
you have recited to me in a manner a little too favorable for 
an easy credence of them on my part. However, I will hope 
that there will be something solid among so many novelties 
with which you desire to regale me. In this case you will find 
me very docile. You know that it was always my disposition 
to surrender myself to reason, and that I sometimes took the 
name of Philalethes. This is why, if you please, we will now 
make use of these two names which are so congruous with our 
mental constitution and methods. There are means of pro- 
ceeding to the trial, for — since you have read the book of the 

1 Oil tlu; 1-elation of Le)1)nitz to Sp)noz<a, see Leibniz u. Spinoza. Ein 
Beitrajj; zur EritwickluugSKescliiehte der Leil)nizi.sclu!n Pliilosophie. Von Prof. 
Dr. Ludwi}^ Stein. Mit neunzehn Ineditis aus dcun Naclilass von Leibniz. 
Berlin: G. Reiincr, WM. pp. xvii., '.m2. Also " Mind," No. (W, p. 2!IS ; No. (W, pp. 
44.3 sq., the latter an extended note on Stein's book by Prof. George Groom 
Robertson, the late editor of " Mind." — Tii. 



.•f 



70 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

celebrated Englishman, whieli gives me so much satisfaction 
and which treats a good part of the subjects of which you 
were just speaking, and above all, the analysis of our ideas and 
knowledge — it will be the shortest way to follow the thread 
of this work, and to see what you will have to say. 
Th. I approve your proposition. Here is the book. 
§ 1. Ph. [I have read this book so thoroughly that I have 
retained even its expressions, which I shall be careful to fol- 
low. Thus I shall not need to recur to the book, except at 
certain junctures where we shall judge it necessary. We shall 
speak first of the origin of ideas or notions (Book I.), then 
of the different kinds of ideas (Book II.), and of the words 
that serve to express them (Book III.), lastly of the knowl- 
edge and truths which therefrom result (Book IV.) ; and it is 
this last part which will occupy us the most. (As for the ori- 
gin of ideas, I believe, with this author and a multitude of 
clever persons, that there are no innate ideas nor innate prin- 
ciples. ]"\ And, in order to I'efute the error of those who admit 
them, it is sufficient to show, as it appears eventually, that 
there is no need of them, and that men can acquire all their 
knowledge without the aid of any innate impression.) 

Th. [You know, Philalethes, that I have been for a long 
time of another opinion ; jthat I have always held, as I still 
hold, to the innate idea of God, which Descartes maintained, 
and as a consequence to the other innate ideas, which cannot 
come to us from the senses) Now, I go still farther in con- 
formity to the new system, and I believe even that all the 
thoughts and acts of our soul come from its own depths, with 
no possibility of their being given to it by the senses, as you 
shall see in the sequel. But at present I will put this investi- 
gation aside, and, accommodating myself to the received ex- 
pressions, since in fact they are good and tenable, and one can 
say in a certain sense that the external senses are in part . 
causes of our thoughts, I shall consider how in my 'opinion 
one must say even in the common system (speaking of the 
action of bodies upon the soul, as the Copernicans speak with 
other men of the movement of the sun, and with cause), fthat 
there are some ideas and some principles which do not come to 
' us from the senses, and which we find in ourselves without form- 
ing them, although the senses give us occasion to perceive them.V 



cii. i] ON HUMAN UNDERSTANDING 71 

I imagine that your clever author has remarked tliat under the -. 

name of innate principles one often maintains his prejudices, / 
and wishes to free himself from the trouble of discussion, and 
that this abuse doubtless has stirred up his zeal against this 
suppositions He desired, no doubt, to combat the indolence 
and the superficial manner of thinking of those who, under the 
specious pretext of innate ideas and of truths naturally en- 
graved upon the mind, to which we readily give our consent, 
care nothing about investigating or considering the sources, 
the relations, and the certainty of this knowledge. In that I 
am entirely agreed with him, and I go even farther. I would j . 
that our analysis should not be limited, that definitions should 
be given of all the terms which are capable of definition, and 
that one should demonstrate, or give the means of demonstrat- 
ing, all the axioms which are not primitive, without distin- 
guishing the opinions which men have of them, and without 
caring whether they give their consent or not. There would 
be more profit in this than one thinks. But it seems that the 
author has been carried too far on the other side by his zeal, 
otherwise very praiseworthy^! ( He has not sufficiently distiri-^ • 
guished, in my opinion, the origin of the necessary truthSjj^ 
whose source is in the understanding, from that of the truths 
of fact drawn from the experience of the senses, and even 
from those confused perceptions which are in us^ You see, 
then, that I do not agree with what you lay down as factj 
— that we can acquire all our knowledge without the need of 
innate impressions. And the sequel will show which of us is 
right.] 

§ 2. Ph. We shall see it indeed. I grant you, my dear The- 
ophilus, that there is no opinion more commonly received than 
that which establishes the existence of certain principles of ; ; 
truth in which men generally agree ; this is why they are 
called general notions, kolvoI evvotat ; whence it is inferred 
that these principles must be so many impressions which our 
minds receive with their existence. § 3. But though it were 
certain that there are some principles in which the entire 
human race is agreed, ^his universal consent would not prove 
that they are innate if one can show, as I believe he can, an- 
other way through which men have been able to reach this 
aniformity of opinion. \ § 4. But, what is much worse, this 



72 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

universal consent is nowhere found, not even with regard to 
these two celebrated speculative principles (for we shall speak 
about the practical ones later), that whatever is, is; and that 
it is imp)Ossible for a thing to be and not to be at the same 
time. For there is a large part of the human race to which 
these two propositions, which will pass doubtless for neces- 
sary truths and for axioms with you, are not even known, 

Th. [I do not ground the certainty of innate principles upon 
universal consent, for I have already told you, Philalethes, 
that my opinion is that we ought to labor to be able to demon- 
strate all the axioms which are not primitive. I grant you 
also that a consent very general, but which is not universal, 
may come from a tradition diffused throughout the human 
race, as the practice of smoking tobacco has been received by 
nearly all nations in less than a century, although some island- 
ers have been found who, not being acquainted with fire even, 
were unable to smoke. Thus some clever people, even among 
theologians, but of the party of Arminius,^ have believed that 
the knowledge of the Deity came from a very ancient and very 
general tradition ; ^find I believe indeed that instruction has 
confirmed and rectified this knowledge.'| It appears, however, 
that nature has contributed to its attainment without learning; 
the marvels of the universe have made us think of a superior 
powder. A child born deaf and dumb has been seen to show 
veneration for the full moon, and nations have been found, 
who seemed not to ''have learned anything of other peoples, 
fearing invisible powers. (l grant you, my dear Philalethes, that 
this is not yet the idea of God that we have and ask for ; but 
this idea itself does not cease to be in the depths of our souls, 
without being put there, as w^e shall see, and the eternal laws 
of God are in part engraved thereon in a manner still more 
legible and by a species of instinct, j But they are practical 
principles of which we shall also have occasion to speak. It 
must be admitted, however, that the inclination we have to 
recognize the idea of God is in human nature. And, even if 
the first instruction therein should be attributed to revelation, 
the readiness which men have always shown to receive this 
doctrine comes from the nature of their souls.^ {But we will 

1 James Arminius, 1.560-1609, a distinj^ished Dutch theologian. —Tk. 

2 From this point on Gerhardt, whose edition, it will be remembered, is the 



cii. i] ON HUMAN UNDERSTANmNG 73 

suppose that these ideas which are innate comprehend incom- 
patible notions.] 

§ 19. Ph. Although you maintain that these particular and 
self-evident propositions, whose truth is recognized as soon as 
one hears them stated (as that green is not red), are received 
as consequences of these other more general propositions, 
which are regarded as so many innate principles, it seems that 
you do not at all consider that these particular propositions 
are received as indubitable truths by those who have no knowl- 
edge of these more general maxims. 

Til. I have already replied to that above. We build on these 
general maxims as we build upon the majors, which are sup- 
pressed when we reason by enthymemes ; ^or, although very 
often we do not think distinctly of what we do in reasoning 
any more than of what we do in walking and leaping, it is 
always true that the force of the conclusion consists in part in 
that which is suppressed and could not elsewhere arise, as you 
will find should you wish to prove it. i 

§ 20. Ph. But it seems that general and abstract ideas are 
more foreign to our mind [than notions and particular truths ; 
consequently particular truths will be more natural to the 
mind than the principle of contradiction, of which you admit 
they are only the application]. 

Th. It is true that we commence sooner to perceive particu- 

basis of the present translation, transposes the text as given by Erdmann and 
Jacques as follows : " Mais nous jugerons que ces idees qui sont innees, ren- 
fernient des notions incompatililes," the first three words of which will be 
found in Erdmann, p. 207, b., about two-thirds down the page, Jacques, Vol. 1, 
p. 29, about two-tliirds down, the remainder in Erdmann, p. 211, a., at the 
middle of the page, Jacques, p. 3G, first third, just preceding § 19 in each case, 
whence the three texts go on in agreement until § 20, G., p. 72, E., p. 212, b., 
J., p. 39. Here the Gerhardt text lias the following: " S'il y adesverites inne'es, 
ne faut il pas qu'il y ait dans la suite, que la doctrine externe ne fait qu'exciter 
icy ce que est en nous " : taking up with the words " dans la suite," the text 
as given by E., p. 207, b., J., p. 29, where it previously left it, the three texts 
continuing again in agreement until the words " des qu'on s'appercoit," G., p. 
79, last third, E., 211, a., at the middle, J., ."(!, first third, whence G. complet(^s 
his senten(!e witli the last three words of the first sentence of § 2(i, as giv<!n by 
E., 212, b., J., .'59, from which i)oint again the tliree texts substantially agree 
to the end of Chap. 1. It may be added that tlie texts of Erdniann, Jacques, 
and Janet follow the order of Locke's Essay. Why Gerhardt has transposed 
the text in his edition, I do not know, as ho has not alluded to the matter. 
From his statement that " the prescmt impression has Ixu^n lu'wly compai'ed 
witli the original, so far as it is still extant " (Introduction, j). 10), I presume 
that the transposition is due to his fidelity to this original. — Tk. 



74 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

lar truths when we commence with ideas more complex and 
gross ; but that does not prevent the order of nature from com- 
mencing with the most simple, and the proof of the more par- 
ticular truths from depending upon the more general, of which 
they are only examples. And when we Avish to consider what 
is in us virtually and before all ax)perception, Ave are right in 
commencing with the most simple. For the general principles 
enter into our thoughts, of which they form the soul and the 
connection. They are as necessary thereto as the muscles and 
sinews are for walking, although we do not at all think of 
them. 'The mind leans upon these principles every moment, 
but it does not come so easily to distinguish them and to rep- 
resent them distinctly and separately, because that demands 
great attention to its acts, and the majority of people, little 
accustomed to think, has little of it./ Have not the Chinese 
like ourselves articulate sounds ? and yet being attached to 
another manner of writing, they have not yet thought of 
making an alphabet of these sounds. Thus it is that one 
possesses many things without knowing it.) 

§ 21. Ph. If the mind acquiesces so promptly in certain 
truths, cannot that acquiescence come from the consideration 
itself of the nature of things, which does not allow it to judge 
of them otherwise, rather than from the consideration that 
these propositions are engraved by nature in the mind ? 

Til. Both are true. The nature of things and the nature of 
mind agree. And since you oppose the consideration of the 
thing to the apperception of' that which is engraven in the 
mind, this objection itself shows, sir, that those whose side you 
take understand /by innate truths only those which would be 
approved naturally as by instinct, and even without knoAving 
it, unless confusedly) There are some of this nature, and we 
shall have occasion to speak of,ibeTftr^ But what is called 7iat- 
ural light supposes a distinct^nowled^e, and very often the 
consideration of the nature of tEln^ST's nothing else than the 
knowledge of the nature of our mind,(and of these innate ideas 
Avhich we have no need to seek outside^ \Hius I call innate 
the trutl^s which need only this consideration for their verifi- 
cation. )^ have already replied (§ 5) to the objection (§ 22) 
which claimed that when it is said that innate ifotiolTS are 
implicitly in the mind, the statement must mean simph^ that 



CH. i] ON HUMAN UNDERSTANDING 75 

it has the faculty of knowing them ; for I have pointed out 
that besides this it has the faculty of finding them in itself, 
and the disposition to approve them when it thinks of them as 
it should. ) 

§J2^. Ph. It seems, then, that you claim that those to whom 
these general maxims are proposed for the first time learn 
nothing which is entirely new to them. But it is clear that \^'"^ 
they learn first the names, then the truths, and even the ideas 
upon which these truths rest. 

Th. The question here is not of names, which are in some 
sense arbitrary, while ideas and truths are natural. But, with 
respect to these ideas and truths, you attribute to us, sir, a 
doctrine which we have strongly repudiated ;^ for I agree that 
we learn ideas and innate truths either in considering their 
source, or in verifying them through experienc^ Thus I do 
not make the supposition which you aver, as if, in the case of 
which you speak, we learned nothing new. And I cannot 
admit tliis proposition : 'cti/ that one learns is not innate^ The-- 
JiDitlis of numbers are^in.-u«, and we are ijot left to learn them, ' 
either by drawing them from their source when we learn them /Y"^ 
through demonstrative proof (which shows that they are in- 
nate), or by testing them in examples, as do ordinary arithme- 
ticians, who, in default of a knowledge of the proofs, learn 
^their rules only by tradition, and, at most, before teaching 
them, justify them by experience, which they continue as far 
as they think expedient. , And sometimes even a very skilful 
mathematician, not knowing the s5u.rce of another's discovery, 
is obliged to content himself with this method of induction in 
examining it ; as did a celebrated writer at Paris, when I was 
there, who continued a tolerably long time the examinatio*n of 
my aritlimetical tetragonism, comparing it with the numbers 
of Ludolphe,' believing he had found therein some error ; and 
he had reason to doubt until some one communicated to him 
the demonstration, which for us dispenses with these tests, 
which could always continue without ever being perfectly 
certain. And it is this very thing, namely, the imperfection 
of inductions, which may yet be verified by instances of expe- 
rience. For there are progressions in which one can go very 

1 Jolm .Tol) Ludolplic, 1049-1711: his Tcirui/onomclria Tabularia, Frank- 
fort, lOilO. —Tr. 



7G LEIBNITZ'S CRITIQUE OF LOCKE [hk. i 

far before noticing the changes and the hxws that are found 
there. 

Ph. But is it not possible that not only the terms or words 
which we use, but even the ideas, come to us from without ? 

Th.ylt would then be necessary that we should be ourselves 
outside of ourselves, for the intellectual or reflective ideas are 
derived from our mind) audi should much like to know how 
we could have the idea of being if we were not beings our- 
selves, and did not thus find being in ourselves. 
" Ph. But what do you say, sir, to this challenge of one of my 
friends ? If any one, says he, can find a proposition whose 
ideas are innate, that he can name to me, he would do me a 
very great favor. 

Th. I would name the propositions of arithmetic and geome- 
try, which are all of this nature ; and, as regards necessary 
truths, no others could be found. 

§ 25. Ph. That will appear strange to most people. Can it 
be said that the most difficult and the most profound sciences 
are innate ? 

Th. Their actual knowledge is not, but much that may be 
ifcalled virtual knowledge is innate, as the figure traced by 
the veins of the marble is in the marble, before one discovers 
them in working.) ^ ^ 

Ph. But is it possible that children, while receiving notions 
that come to them from without, and giving them their con- 
sent, may have no knowledge of those which you suppose to 
be inborn with them, and to make, as it were, a part of their 
mind, in Avhich they are, you say, imprinted in ineffaceable 
characters in order to serve as a foundation ? If that were so, 
nature would have taken trouble for nothing, or, at least, she 
would have badly engraved their characters, since they cannot 
be perceived by the eyes which see very well other things. 

Th. p'he apperception of that which is in us depends upon 
attention and order^ Now, not only is it possible, but it is also 
proper, that children give more atteiition to the ideas of the 
senses, because the attention is regulated by the need. The 
outcome, however, shows in the sequel that nature has not 
uselessly given herself the trouble of impressing upon us in- 
nate knowledge, since without it there would be no means of 
attaining actual knowledge of the truths necessary in the 



CH. i] ON HUMAN UNDERSTANDING 77 

demonstrative sciences, and the reasons of facts ; and we 
should possess nothing above the beasts. 

§ 26. P/i.( If there are innate truths, does it not necessarily % 
follow that the external doctrine only stirs up here what is in ~r— 
us ?\ I conclude that a consent sufficiently general among men ^'/ ^ 
(is an indication, and not a demonstration, of an innate princi- 
ple ;1 but that the exact and decisive proof of these principles 
consist^,J-n showing that their certitude comes only from what 
is in us. I To reply further to what you say against the general 
approba:t!on which is given to the two great speculative prin- 
ciples, which are, nevertheless, the best established, I may say 
to you that even if they were not known they would not cease 
(to be innate, because they are recognized as soon as heard y 
but I will add further that at bottom everybody knows them, ^ a^, <>, 
and makes use at every moment of the principle of contradic- q^„,^ 
tion (for example) without considering it distinctly ; and 
there is no barbarian who, in an affair of any moment, is not 
olfended by the conduct of a liar who contradicts himself. .i^^„ 
Thus, these maxims are employed without an express consid- 
eration of them. (And in nearly the same way Ave have virtu- 
ally in the mind the propositions suppressed in enthymemes, 
which are set aside not only externally, but further in our 
thought/ 

§ 5. Ph. [What you say of this virtual knowledge and of 
these internal suppressions svirprises me] jffor to say that"' 
there are truths imprinted upon the soul which it does not 
])erceive is, it seems to me, a veritable contradiction./ 

Th., [If you are thus prejudiced, I am not astonished that 
you reject innate knowledge. But I am astonished that the 
tliouglit has not occurred to you tha? we have an infinite amount 
of knowledge of which we are not always conscious, not even ' 
when we need it.J It is for the memory to preserve this, and 
for the reminiscence to represent it to us, as it often, but not 
always, does at need. That is very well called remembrance 
(mbvenire), for reminiscence needs some aid. And it must 
certainly be that in this multiplicity of our knowledge we are 
determined by something to renew one part rather than another, 
since it is impossil)le to think distinctly and at once of every- 
thing we know.] 

Ph. In that I believe you are riglit;and this too general 



78 LEIBNITZS CRITIQUE OF LOCKE [hk. i 

affirmation, that we always perceive all the truths which are 
in our soul, escaped me without my having given it sufficient 
attention. But you will have a little more trouble in reply- 
ing to what I am going to show you. That is, that if you can 
say of some particular proposition that it is innate, you could 
maintain by the same reasoning that all propositions which 
are reasonable, and which the mind could always regard as 
such, are already impressed upon the soul. 

Th. I agree with you in regard to pure ideas, which I oppose 
to the phantoms of the senses, and in regard to necessary 
truths, or those of the reason, which I oppose to truths of 
fact. In this sense it must be said that all arithmetic and all 
geometry are innate, and are in us virtually, so that we can 
find them there if we consider attentively and set in order 
what we already have in the mind, without making use of any 
truth learned through experience or through the tradition of 
another, as Plato has shown in a dialogue ^ in which he intro- 
duces Socrates leading a child to abstract truths b}" questions 
alone without giving him any information. ( We can then 
make for ourselves these sciences in our studj^, and even with 
closed eyes, without learning through sight or even through 
touch the truths which we need ; although it is true that we 
would not consider the ideas in question if we had never seen 
or touched anything. For through an admirable economy of 
nature/ we cannot have abstract thoughts which have no need 
whatever of anything sensible,] when that would only be of 
such a character as are the forms of the letters and the sounds, 
although there is no necessary connection between such arbi- 
trary characters and such thoughts. And if the sensible out- 
lines were not requisite, the pre-established harmony between 
soul and body, of which I shall have occasion to sj)eak more 
full}", would have no place. But that does not prevent the 
mind from taking necessary ideas from itself. You see also 
sometimes how it can go far without any aid, by a logic and 
arithmetic purely natural, as that Swedish youth who, in culti- 
vating his own (mind), went so far as to make great calcula- 
tions immediately in his head without having learned the 
common method of computation, or even to read and write, it 
I remember correctly what has been told me of him. It is 
^ Mem, 82s5.— Tr. 



CH. I] ON HUMAN UNDERSTANDING 79 

true that he cannot work out intricate problems, such as those 
which demand the extraction of roots. But that does not at 
all prevent him from being able still to draw them from its 
depths by some new turn of mind. Thus that proves only 
that there are degrees in the difficulty of perceiving what is in 
us. There are innate principles which are common and very 
,easy to all ; there are theorems which are discovered likewise 
at once, and which compose the natural sciences, which are 
more understood in one case than in another. ' Finally, in a 
larger sense, which it is well to employ in order to have notions 
more comprehensive and more determinate, all truths which 
can be drawn from primitive innate knowledge can still be 
called innate, because the mind can draw them from its own 
depths, although often it would not be an easy thing so to do. 
But, if any one gives another meaning to the terms, I do not 
wish to dispute about words. 

Ph. [I have agreed with you that we can have in the soul 
what we do not perceive there, for we do not always remem- 
ber at once all that we know, but it must be always what we 
liave learned or have known in former times expressly. Thus]- 
if we can say that a thing is in the soul, although the soul 
lias not yet known it, (this can only be because it has the 
cajjacity or faculty of knowing it. ) 

Th. [Why could not this have still another cause, such as 
tlie soul's being able to have this thing within it without its •• 
being perceived ?jfor since an acquired knowledge can be con- 
I caled therein byHhe memory, as you admit, why could not . \ 
nature have also concealed therein some original knowledge?). ^ 
Must everything that is natural to a substance which knows 
itself be known by it actually at once ?, Cannot and must not 
this substance (such as our soul) have many jiroperties and 
affections which it is impossible to consider all at once and all V 
together ? It was the opinion of the Platonists that all our j^ 
knowledge was reminiscence, and that thus the truths which V- 
^he soul has brought with the birth of the man, and which \ 
are called innate, must be the remains of an express anterior 
knowledge.^ But this opinion has no foundation; and it is 
easy to believe that the soul must already have innate knowl- 
edge in the precedent state (if there were any pre-existence), 
however remote it might be, entirely as here : it would then 




80 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

have to come also from another precedent state, or ^ it would 
be finally innate, or at least concreate ; or else it would be 
needful to go to infinity and to make souls eternal, in which 
case this knowledge would be innate in fact, because it would 
never have commenced in the soul ; and if any one claimed 
that each anterior state has had something from another more 
anterior, which it has not left to the succeeding, the reply will 
be made that it is manifest that certain evident truths must 
have been in all these states ; and in whatever manner it may 
be taken, it is always clear in all states of the soul that neces- 
sary truths are iunateji, and are proved by what is within, it 
not being possible to establish them through experience, as we 
establish truths of fact. Why should it be necessary also 
that we could have no possession in the soul of w^hich we had 
never made use ? And is it the same thing to have a thing 
without using it as to have only the faculty of acquiring it ? 
If that were so, we should never possess anything but the 
things which we enjoy; instead of which, we know that, be- 
sides the faculty and the object, some disposition in the fac- 
ulty or in the object, or in both, is often necessary, that the 
faculty may exercise itself upon the object.] 

Ph. Taking it in that wa-y, we could say that there are 
(truths written in the soul which the soul has, however, never 
known, and which, indeed, it will never know. This appears 
to me strange. 

Th. [I see there no absurdity, although in that case you 
could not be assured that there are such truths. /For things 
more exalted than those Avhich we can know in this present 
course of life may be developed some time in our souls, when 
they are in another state.] ) * 

Fh. But suppose there are truths which could be imprinted 
upon the understanding without its perceiving them ; f I do 
not see how, in relation to their origin, they could differ from 
the truths which it is on]}^ capable of knowing, j 

Th. [The mind is not only capable of knowing them, but 
further of finding them in itself ; j and, if it had only the sim- 
ple capacity of receiving knowledge, or the passive power there- 
for, as indeterminate as that which the wax has for receiving 
figures and the blank tablet for receiving letters, it would not 

1 The reading of Gerhardt and Erdmann ; Jacques has *' oii," where. — Tr. 



vn. I] ON HUMAN UNDERSTANDING 81 

Ije tlie source of necessary truths, as I have just shown that it' ' 
is; for it is incontestable that the senses do not suffice to 1,0*. 
show their necessity, and that thus the mind has a disposition ; • 
(active as well as passive) to draw them itself from its own 
depths ; Although the senses are necessary to give it the occa- 
sion and attention for this, and to carry it to some rather than 
to others. I You see, then, sir, that these elsewhere very clever 
persons wno are of another opinion appear not to have thought 
enough upon the consequences of the difference which there is 
between necessary or eternal truths and the truths of experi- 
ence, as I have already observed, and as all our discussion 
sliows. The original proof of the necessary truths comes 
from the understanding alone, and the other truths come from 
experience or from the observation of the senses. Our mind 
is capable of knowing both; but it is the source of the former, 
;aid, whatever number of particular experiences we may have 
(if a universal truth, we could not be assured of it forever by 
induction without knowing its necessity through the reason. 

Ph. But is it not true that if the words, to be in the under- 
sfaitdiiig, involve something positive, they signify to be per- 
ceived and comprehended by the understanding ? 

Th. They signify to us wholly another thing. It is enough 
that what is in the understanding can be found there, and that 
tlie sources or original proofs of the truths which are in ques- 
lion are only in the understanding i , the senses can. hint at, * 
justify, and confirm these truths, buu cannot demonstrate their 
infallible and perpetual certainty. 

§ 11. Ph. ISTevertheless, all those who will take the trouble 
to reflect with a little attention upon the operations of the 
understanding will find that this consent, which the mind gives 
irithont difficulti/ to certain truths, depends upon the faculty 
ci the human mind.^ 

Th. Very well. jBut it is this particular relation of the 
liuman mind to these truths which renders the exercise of the 
faculty easy and natural in respect to them, and which causes 
them to be called innate.] It is not, then, a naked faculty 
which consists in the mere possibility of understanding them ; 
it is a disposition; an aptitude, a preformation, which determines 
our soul and wliich makes it possibh; for them to be derived 
from it. Just as there is the difference between the figui'cs 

G 



82 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

which are given to the stone or the marble indifferently, and 
between those which its veins already indicate, or are disposed 
to indicate, if the workman profits by them. 

Fh. But is it not true that the truths are subsequent to the 
ideas of which they are born ? Xow, the ideas come from 
the senses. 

. Th. The intellectual ideas, which are the sourQe_Qf_neces- 
sary truths, do not come from the senses ; and you admit that 
there are some ideas which are due to the reflection of the 
mind upon itself. For the rest, it is true that the express 
knowledge of truths is subsequent (tempore vel natura) to the 
express knowledge of ideas ; as the nature of truths depends 
upon the nature of ideas, before we expressly form one or the 
other, and the truths, into which enter ideas which come from 
the senses, depend upon the senses, at least in part. But the 
ideas which come from the senses are confused, and the truths 
which depend upon them are likewise confused, at least in 
part; while the intellectual ideas, and the truths dependent 
upon them, are distinct, and neither the one nor the other 
have their origin in the senses, although it may be true that 
we would never think of them without the senses. 

Ph. But, in 3'Our view, numbers are intellectual ideas, and 
yet it is found that the difficulty therein depends upon the 
express formation of the ideas ; for example, a man knows 
that 18 and 19 equal 37 with the same evidence that he knows 
that 1 and 2 equal 3 ; but a child does not know the first propo- 
sition so soon as the second, a condition arising from the fact 
that he has not formed the ideas as soon as the words. 

Th. I can agree with you that often the difficulty in the 
express formation of truths depends upon that in the express 
formation of ideas. Yet I believe that in jowx example the 
question concerns the use of ideas already formed. For those 
who have learned to count as far as 10, and the method of 
passing farther on by a certain repetition of tens, understand 
without difficulty what are 18, 19, 37 ; viz., 1, 2, or 3 times 10 
with 8, or 9, or 7 ; but, in order to draw from it that 18 plus 
19 make 37, more attention is necessary than to know that 2 
plus 1 are 3, which at bottom is only the definition of 3. 

§ 18. P/i.C Furnishing propositions in which you infallibly 
acquiesce as soon as you hear them is not a privilege attached 



CH. i] ON HUMAN UNDERSTANDING 83 

to the numbers or to the ideas, which you call intellectual. J 
You meet these in physics and in all the other sciences, and 
the senses even furnish them. For example, this proposition : 
tioo bodies cannot be in the same place at the same time, is a 
truth of which you are not otherwise convinced than of the 
following maxims : It is i7n2:>ossible for a thing to be and not 
to be in the same time; white is not red; the square is not a 
circle; yellowness is not sweetness. 

Th. There is a difference between these propositions. The 
first, which declares the impenetrability of bodies, needs proof. 
All those who believe in true and strictly formed condensa- 
tion and rarefaction, as the Peripatetics and the late Chevalier 
Digby,^ reject it, in fact ; without speaking of the Christians 
who believe, for the most part, that the contrary view — 
namely, the penetration of space — is possible to God. But the 
other propositions are identical, or very nearly so, and identi- 
cal or immediate propositions do not admit of proof. Those 
who look upon the senses as furnishing them, as that one who 
says that yellowness is not sweetness, have not applied the 
general identical maxim to particular cases. 

Ph. Every proposition composed of two different ideas, of 
which one is the denial of the other — for example, that the 
sipiare is not a circle, that to be yellow is not to be sweet — 
will be as certainly received as indu.bitable, as soon as its 
terms are understood, as this general maxim : It is impossible 
for a thing to be and not to be in the same time. 

Th. That is, the one (namely, the general maxim) is the 
principle, and the other (that is to say, the negation of one 
idea by another opposed to it) is its application. 

Ph. It seems .to me rather that the maxim depends upon 
this negation, which is its ground; and that it is, besides, 
much easier to understand that what is the same thing is not 
different, than the maxim which rejects the contradictions. 
Now, according to this statement, it will be necessary for you 
to admit as innate truths an infinite number of propositions of 
this kind which deny one idea by another without speaking 

' Sir Koiiclin Dij^by, 1G0;5-10()5, an cmiiuiiit English pliysic'il ijliilosophor, 
wlio livi^d for a time in Franco, where he enjoyed the friendsliip of Descartes 
and otli(!r learned men, and wrote liis Treatise on the Nature of Bodies and 
other woi'ks. — Tr. 



84 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

of other tvutlis. (Add to this, that a proposition cannot be 
innate unless the ideas of which it is composed are innate j 
it will be necessary to suppose that all the ideas which we 
have of colors, sounds, tastes, figures, etc., are innate. 

Th. I do not well see how this : what is the same thing is 
not different, is the origin of the principle of contradiction, 
and easier ; for it appears to me that you give yourself more 
freedom in advancing that A is not B than in saying that A is 
not non-A. And the reason that prevents A from being B is 
that B includes non-A. For the rest this proposition : the 
siveet is not the hitter, is not innate, according to the sense 
which we have given to the term innate truth. For the sen- 
sations of sweet and bitter come from the external senses. 
Thus it is a mixed conclusion {liyhrida conclusio), where the 
axiom is applied to a sensible truth. But as regards this 
proposition : the square is not a circle, you can affirm that it 
is innate, for, in considering it, you make a subsumption or 
application of the principle of contradiction to Avhat the un- 
derstanding itself furnishes as soon as you are conscious of 
innate thoughts. 

TJi. Not at all, for the thoughts are acts, and the knowledge 
or the truths, in so far as they are within us, even when we 
do not think of them, are habitudes or dispositions ; and we 
are well acquainted with things of which we think but little. 

Ph. (it is very difiicult to conceive that a truth may be in 
the mind if the mind has never thought of that truth^ 

Th. It is as if some one said it is difficult to conceive that 
there are veins in the marble before we have discovered them. 
This objection seems also to approach a little too much the 
begging of the question.^ All those who admit innate truths, 
without grounding them in the Platonic reminiscence, admit 
some of which they have not yet thought. Besides, this 
reasoning proves too much ; for, if truths are thoughts, we 
shall be deprived not only of the truths of which we have 
never thought, but also of those of Avhich we have thought, 
and of which we no longer actually think ; and if truths are 
not thoughts, but habits and aptitudes, natural or acquired, 
nothiug prevents there being in us some of which we have 
never thought, nor will ever think. 

1 Petitio prineipii. — Tr. 



CH. ii] ON HUMAN UNDERSTANDING 85 

§ 27. Ph. If general maxims were innate, they would appear 
morej^ividly in the mind of certain persons where, however, 
we see no trace of them ; I may mention children, idiots, and 
savages,^ for of all men these are they who have the mind 
less altered and corrupted by custom and by the impress of 
extraneous opinions. 

Th. I believe we must reason here very differently. (Innate 
maxims appear only through the attention which is given to 
them ;T but these persons have little of it, or have it for 
entirely different things. Their thoughts are mostly confined 
to the needs of the body ; and it is reasonable tliat pure and 
detached thoughts be the reward of cares more noble. It is 
true that children and savages have the mind less altered by 
customs, but they also have it exalted by the teaching which 
gives attention. It would not be very just that the brightest 
lights should shine better in minds which less deserve them, 
and which are enveloped in thicker clouds. I would not then 
have one give too much honor to ignorance and barbarism 
when one is as learned and as clever as you are, Philalethes, 
as well as your excellent author ; that would be lowering the 
gifts of God. Some one will say that the more ignorant we 
are, the more we approach the advantage of a block of marble 
or of a piece of wood, which are infallible and sinless. But, 
unfortunately, it is not by ignorance that we approach this 
advantage ; ('and, as far as we are capable of knowledge, Ave 
sin in neglfecting to acquire it, and we shall fail so much the 
more easily as we are less instructed. 3 



CHAPTER II 

NO INNATE PliACTICAL PRINCIPLES 

§ 1. Ph. Ethics is a demonstrative science, and yet it has 

no innate principles. And, indeed, it would be very difiicult 

to produce a rule of ethics of a nature to be settled by an 

assent as general and as prompt as this maxim : ^V^HUever 

is, is. 

^ For an excellent exposition of the ronteut of tlic Icnn ravage, of. Andrew 
I.ans, Mijth, liitual, and Relifiion, Vol. 1, p. Ml, :\m\ note; also chap. .'{, i>p. 
4() aq., T.oniloii : I>oiii;nKUis, Green, & Cf)., l.S,S7. — Tii. 



86 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

Th. It is absolutely impossible tliat there be truths of 

reason as evident as those which are identical or immediate. 

And, although you can truly say that ethics has principles 

* which are not demonstrable,^nd that one of the first and most 

practical is, that we ought to pursue joy and avoid sorrow, it 

, is needful to add that this is not a truth which is known 

. purely by reason, since it is based upon internal experience, or 

■ upon confused knowledge, for we do not feel what jo}^ or 

sadness is.) 

Ph. It is only through processes of reasoning, through lan- 
guage, and through some mental application, that you can be 
assured of practical truths. 

Th. Though that were so, they would not be less innate. 
However, the maxim I just adduced appears of another na- 
. , ture ; it is not known by the reason, but, so to speak, by an 
instinct. (It is an innate principle, but it does not form a 
part of the natural light, for it is not known luminously. But 
this principle admitted, you can draw from it scientific con- 
sequences, and I commend most heartily what you just said of 
ethics as a demonstrative science. Let us note also that it 
teaches truths so evident that thieves, pirates, and bandits are 
forced to observe them among themselves. 

§ 2. Ph. But bandits keep the rules of justice among them- 
selves without considering them as innate principles. 

Th. What matters it ? Does the world concern itself about 
questions of theory ? 

P7i. They observe the maxims of justice only as convenient 
rules, the practice of which is absolutely necessary to the con- 
servation of their society. 

TJi. [Very well. You could say nothing better in general in 
respect to all men. ^nd thus it is that these laws are written 
in the soul, namely, as the consequences of our preservation 
and of our true welfare.) Do you imagine that we suppose 
that truths are in the understanding as independent the one of 
the other as the edicts of the praetor were on his placard or 
album? I put aside here the instinct which prompts man to 
love man, of which I shall presently speak, for now I wish to 
speak only of truths in so far as they are known by tJie reason. 
I admit, also, that certain rules of justice cannot be demon- 
strated, in all their extent and perfection, without supposing 



CH. iij ON HUMAN UNDERSTANDING 87 

the existence of God and the immortality of the soul, and 
these, where the instinct of humanity does not impel us, are 
written in the soul only as other derivative truths.] Those, 
however, who base justice only upon the necessities of this life 
and upon the need they have of it, rather than upon the pleas- 
ure they ought to take in it, which is the greatest when God 
is its ground, are liable to resemble a little the society of 
bandits. 

Sit spes fallendi, miscebunt sacra profanis.i 

§ 3. Ph. I agree with you that nature has put in all men 
the desire for happiness and a strong aversion to misery. 
These are(</ie truly innate practical principles, and principles 
which, according to the purpose of every practical principle, 
have a continual influence upon all our actions.) But they are 
inclinations of the soul toward the good, and not impressions ^ 
of some truth which is written in our understanding. 

Th. [I am delighted, sir, to see that you admit in effect 
innate truths, as I shall presently say. This principle agrees 
sufficiently with that which I just indicated, which prompts 
us to seek joy and shun sorrow. For felicity is only a last- 
ing joy. Our inclination, however, does not tend to felicity 
proper, but to joy — that is to say, to the present ; it is the 
reason which prompts to future and enduring welfare. Now, 
the inclination, expressed by the understanding, passes into a 
precept or practical truth ; ^nd if the inclination is innate, the. 
truth is innate also,! there being/ nothing in the soul which 
may not be expressed in the understanding, but not always by 
a consideration actually distinct^ as I have sufficiently shown. 
The instincts also are not always practical ; there are some 
which contain theoretical truths, and such are the internal 
principles of the sciences and of reasoning, when, without rec- 
ognizing the reason in them, we employ them by a natural 
instinct. And in this sense you cannot dispense with the 
recognition of innate principles, even though you might be 
willing to deny that derivative truths are innate. Ikit this 
would be a question of name merely after the explanation I 

1 Cf. Kor. Epist., 1, 10, 54. Horace has "miscobis." — Tb. 

2 Erdinaiin and Jacqiies road, " d(!S imperfections do quelqne verite." Ger- 
hardt reads, "des iin])ressioiis do quelqne veriti'." I.ock<! lias, " inipressions 

-of trnth." Book I., (;liap. 3, § 3. Vol. 1, p. 158, line 5. Bulm's edition.— Tr. 



88 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

have given of what I call innate. And if any one desires to 
give this appellation only to the truths which are received at 
first by instinct, T shall not contest the point with him.] 

Ph. That is well. But if there were in our soul certain 
characters imprinted there by nature, like so many principles 
of knowledge, we could only perceive them acting in us, as we 
feel the influence of the two principles which are constantly 
active in us — namely, the desire of happiness and the fear of 
misery. 

Th. [There are principles of knowledge which influence us 
as constantly in our reasoning processes as these practical prin- 
ciples influence us in our volitions ; for example, everybod}^ 
employs the rules of deduction by a natural logic without 
being aware of it. 

§ 4. Ph. The rules of Morality need to be proved ; they are 
then not innate, like that rule which is the soui*ce of the vir- 
tues which concern societ}^ : Do to another only lohat you would 
have him do to yoxirself. 

Th. You always make me the objection which I have al- 
ready refuted. I agree with you that there are moral rules 
which are not innate princiijles ; but that does not prevent them 
from being innate truths, for a derivative truth will be innate, 
supposing that we can draw it from our mind. \But there are 
innate truths, which we find in us in two ways — by insight 
and by instinct. Those which I have just indicated, show by 
our ideas what natural insight accomplishes. But there are 
conclusions of natural light which are principles in relation 
to instinct/ It is thus that we are prompted to acts of human- 
ity, by instinct because it pleases us, and by reason because it 
is just. There are then in us truths of instinct, which are 
innate principles, which we feel and approve, although we have 
not the proof of them which we obtain, however, when we give 
a reason for this instinct. It is thus that we make use of 
the laws of deduction conformably to a confused knowledge, 
and as by instinct, but logicians show the reason of them, as 
mathematicians also give a reason for what they do without 
thinking in walking and leaping. As for the rule which states 
that we ought to do to others only what we would have them 
do to us, it needs not only proof, but also to be proclaimed. "We 
should Avish too much for ourselves if we could have our own 



CH. II] ON HUMAN UNDERSTANDING 89 

way ; shall we say then that we also owe too much to others ? ^ 
You will tell me that the rule meaus only a just will. But 
thus this rule, very far from being adequate to serve as a 
measure, would itself need one. The true sense of the rule 
is, that the place of another is the true point of view for equi- 
table judgment when Ave attempt it.] 

§ 9. Ph. Bad acts are often committed without any remorse 
of conscience ; for example, when cities are carried by storm, 
the soldiers commit, without scruple, the worst acts ; some 
civilized nations have exposed their children, some Caribbees 
castrate theirs in order to fatten and eat them. Garcilasso de 
la Vega" reports that certain peoples of Peru took prisoners in 
order to make concubines of them, and supported the children 
up to the age of thirteen, after which they ate them,, and 
treated in the same manner the mothers so soon as they no 
longer bore children. In the travels of Baumgarten ^ it is re- 
lated that there was a Santon^ in Egypt who passed for a holy 
man, eo quod non foeminarum unquavi esset ac 2^uero7'icm, sed 
tantum anellarum conctibitor atque mularum. 

Th. Moral science (over and above the instincts like that 
which makes us seek joy and shun sadness) is not otherwise 
innate than is arithmetic, for it depends likewise upon demon- 
strations which internal light furnishes. And as the dem- 
onstrations do not at once leap into sight, it is no great wonder, 
if men do not perceive always and at once all that they pos- 
si!ss in themselves, and do not read quite readily the characters 
of the natural law, which God, according to St. Paul,^ has writ- 
ten in their minds. As morality, however, is more important 
than arithmetic, God has given to man instincts which prompt 

1 This sentence is found in the texts of Erdnianii and Gerhixrdt ; it is w.ant- 
iii,'4 ill tliat of Jacques. — Tr. 

2 Garcilasso de la Vega, 1540-1016, the son of an Inca princess, and a Span- 
ish conqiiei'or, a companion of Pizarro. His CommentarioH realrs was pub- 
lislusd in two parts, the first at Lisbon, IfiOf), sivina; an account of the native 
traditions, customs, and history previous to tlu' Spanish conquest; the second 
under Ihe separate title of Historic! Grnoral dH Porv, Cordova, 1(!17, treating 
of the Spanish conquest. The earlier and more important part of the work 
has been translated, with "learned and ingenious notes," by Clements R. 
Markham, and published in the collection of the Ilakluyt Society, 2 vols., 
London: 1809, 1871.— Tr. 

3 Martin Baumgarten, 147.V15.3.5, Trnrrls tliraiif/h Er/i/pf, Arahin, etc In 
Churchill, O. and J. Col., Vol. 1, 1744. — Tr. 

* Mahometan monk. — Tr. '" Rom. 2 : 15 ; rf. 1 : 11). — Tii. 



90 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

at once and -without reasoning to some portion of that which 
reason ordains ; just as we walk in obedience to the laws 
of mechanics without thinking of these laws, and as we eat, 
not only because eating is necessary for us, but further and 
much more because it gives us pleasure. t5ut these instincts 
do not prompt to action in an invincible way); the passions 
may resist them, prejudices may obscure them, and contrary 
customs alter them. Nevertheless, we agree most frequently 
with these instincts of conscience, and we follow them also 
when stronger impressions do not overcome them. The great- 
est and most healthy part of the human race bears them wit- 
ness. The Orientals, the Greeks and Romans, the Bible 
and the Koran agree in respect to them ; the Mahometan 
police are wont to punish the thing Baumgarten tells of, and 
it would be needful to be as brutalized as the American savage 
in order to approve their customs, full of a cruelty which sur- 
passes even that of the beasts. Yet these same savages per- 
ceive clearly what justice is on other occasions ; ^ and although 
there is no bad practice, perhaps, which may not be authorized 
in some respects and upon some occasions, there are few of 
them, however, which are not condemned very frequently and 
by the larger part of mankind. That Avhich has not been at- 
tained without reason, and was not attained by reasoning alone, 
should be referred in part to the natural instincts. Custom, 
tradition, discipline, are mingled therein, but it is due to in- 
stinct (le naturel ) that custcmi is turned more generally to the 
good side of these duties. (In the same way,^ the tradition of 
God's existence is due to instincij (le naturel). Xow nature 

1 Cf. J. G- Solmrman, The Ethical Import of Darwiuism, pp. 256-260, New 
York": Charles Scribner's Sons, 1887. He states that " some gropings amid the 
general darkness incline me, at least tentatively, to the belief that, apart from 
the domestic virtnes, there is no snch great difference between the morals of 
Christians and the morals of savages" (p. 256). This statement is modified 
further on, pp. 258, 259, and finally takes the following form: " The fighting 
men, actual and potential, in every uncivilized community recognize the same 
rights, obligations, and duties toward one anotlier as constitute the essence of 
civilized morality. You never find a man without a moral nature, a nature 
essentially like our own ; but the objects he includes within the scope of its 
outgoings vary" (p. 259). For the real significance of such facts, cf. Ex- 
Pres. E.'^G. Robinson, of Brown Vmversitj, Principles and Practice of Moral- 
ity, p. 43, Boston: Silver, Burdett & Co., 1888. — Tr. 

"2Gerhardt reads, " C'est comma le naturel," etc.; Erdmann and Jacques, 
" Le naturel," etc. — Tr. 



VH. II] ON HUMAN UNDERSTANDING 91 

gives to man and also to most of the animals affectionate and 
tender feeling for those of their species. The tiger even par- 
cit cognatis mascuUs;^ whence comes this bon mot of a Roman 
jurisconsult, Quia inter omnes homines natura cognationem 
constituit, uncle hominum homini insidiari nefas esse. Spiders 
form almost the only exception, and these eat one another 
to this extent that the female devours the male after having 
enjoyed him. Besides this general instinct of society, which 
may be called philanthropy in man, there are some more par- 
ticular forms of it, as the affection between the male and the 
female, the love which father and mother bear toward the chil- 
dren, which the Greeks call o-Topyr/,^ and other similar inclina- 
tions which make this natural law, or this image of law rather, 
which, according to E-oman jurisconsults, nature has taught 
the animals. But in man in particular there is found a certain 
regard for dignity, for propriety, which leads him to conceal 
the things which lower us, to be sparing of shame, to have 
repugnance for incests, to bury dead bodies, not to eat men at 
all, nor living animals. One is led further to be careful of his 
reputation, even beyond need, and of life ; to be subject to 
remorse of conscience, and to feel these laniatus et ictus, 
these tortures and torments of which Tacitus, following Plato, 
speaks ;^ besides the fear of a future and of a supreme power 
which arises, moreover, naturally enough. There is reality in 
all that ; but at bottom these natural impressions, whatever 
they may be, are only aids to the reason and indices of the 
plan of nature. Custom, education, tradition, reason, contrib- 
ute much, but human nature ceases not to participate therein. 
It is true that without the reason these aids would not suffice 
to give a complete certitude to morals. Finally, will you deny 
that man is naturally led, for example, to witlidraw from vile 
things, under a pretext that races are found who like to speak 
only of filth, that there are some, indeed, whose mode of life 
obliges them to handle excrements, and that there are people 
of Boutan, Avhere those of the king pass as an aromatic ? I 
think tliat you are of my opinion at bottom in regard to these 
natural instincts which tend toward what is right and decent; 

1 Juv. Snt., 15, 159-100. — Tr. 

2 The readiii}< {nom. aropyn) of Erdmann and Jacques. Gerhardt's reading, 
'opy'nv, is evidently an error. — Tu. 3 (Jonjias, 524 E ; Ann. G, G. — Tk. 



92 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

although you will say, perhaps, as you have said with regard 
to the instinct which prompts to joy and felicity, that these 
impressions are not innate truths. But I have already replied 
( tjiat every feeling is the perception of a truth,^nd that the 
statural feeling is the (perception) of an innate trut]i,)but very 
often confused, as are the experiences of the external senses -, 
thus you can distinguish the innate tniths from the natural 
light (which contains only the distinctly knowable), as the 
genus must be distinguished from its species, pince the imiate 
truths comprehend both the instincts and the natural light.] J 

§ 11. Ph. A person who knew the natural limits of justice 
and injustice, and (who) Avould not cease confusing them with 
each other, could only be regarded as the declared enemy of 
the repose and the welfare of the society of which he is a mem- 
ber. But men confuse them every moment, consequently they 
do not knoAv them. 

Th. [That is taking things a little too theoretically. It 
happens every day that men act contrary to their knowledge in 
concealing these (limits) from themselves when they turn the 
mind elsewhere, in order to follow their passions ; otherwise, 
we should not see people eating and drinking what they know 
must cause them sickness and even death. They would not 
neglect their business ; they Avould not do what entire nations 
have done in certain respects. The future and reason rarely 
make so strong an impression as the present and the senses. 
That Italian knew this well, who, before being put to torture, 
proposed to have the gallows continually in sight during the 
torments in order to resist them, and they heard him say some- 
times, " lo ti vedo," which he explained afterward when he had 
escaped. Unless you firmly resolve to look upon the true good 
and the true evil with the purpose of following or shunning 
them, you find yourself carried away, and it happens, with re- 
gard to the most important needs of this life, as it happens with 
regard to paradise and hell in the case of those, indeed, who 
believe in them the most : — 

Cantantur Iiebc, laudantur haec, 

Dicuntur, audiuntur. 
Scribuntur h;ec, legiintur hsec, 

Et lecta negliguiitui-.] 



,11. n] ON HUMAN UNDERSTANDING 93 

Ph. Every principle wluch you suppose innate can only be 
known by each one as just and advantageous. 

Th. [You always return to tliis supposition, wliicli I have 
refuted so many times,(t.hat every innate truth is known 
always and by all.jy 

§ 12. Ph. But a public permission to violate the law proves 
that this law is not innate ; for example, the law requiring the 
love and preservation of children was violated among the 
ancients when they permitted their exposure. 

Th. [This violation supposed, it follows only that you have 
not well read these characters of nature written in our soul, 
but sometimes obscure enough by reason of our excesses, not 
to mention that, in order to have a perfectly clear perception 
of the necessity of duties, men must see the demonstration of 
them — a condition that is rarely fulfilled. If geometry were as 
much opposed to our passions and present interests as is ethics, 
we should contest it and violate it but little less, notwith- 
standing all the demonstrations of Euclid ^ and of Archimedes,' 
which you would call dreams and believe full of paralogisms; 
and Joseph Scaliger, Hobbes,^ and others, who have written 
against Euclid and Archimedes, would not find themselves in 
such a small company as at present. It was only the passion 
for glory, which these authors believed they found in the quad- 
rature of the circle and other difficult problems, which could 

1 Euclid, not to be cnnfonnded with Euclid of Mesara, a pupil of Socrates, 
fouiid(!r of the Me.uarian school, the fundamental principle of whose philosophy- 
was the union of the Eleatic idea of beinrj with the .Socratic idea of the nood. 
Tiie date of neither his hirth nor death is known. Proclus, the Neo-Platonist, 
410-4S5 A.D., says that Euclid lived in the time of Ptolemy I., king of Egypt, 
wlio ivigned from 323-285 B.C., and that he was younger than Plato's associates, 
hut ol.lcr tlian Eratosthenes, " 27()-2— 106,-2 B.C.," "the celebrated scholar 
wliose chronological dates were adopted for the liistoryof pliilosophy" (Zeller, 
Oiiiliiii'ft, §§ ."?, G()), and Archimedes, 287-212 B.C. Proclus preserves P>uclid's 
reply to King Ptolemy, who asked him if thei-e were no easi(!r way to learn 
geometry than by studying his elements. " There is no royal road to geom- 
etry."— Tr. 

2 Thomas Hol)l)es, 1588-1079. The statement of his geometrical principles 
in opposition to those of Euclid is found in the Appendix to tin; English trans- 
lation of the De Corpora, which app(!ared about the middle of 1650, entitled 
Six Lessons to the Professors of Matheniutirs, one of Geomrtni, the other of 
Astronomy, in. the Unirersity of Oxford, English Works, Vol. 7, i)p. iai-,T)0. 
For an account of the coiiti'oversy in wliich these appcariMl, <f. George (Iroom 
Rol)ertsoji, II(,hhes, pp. 167-178 (Philosoi)hical Classics). Edinburgh: William 
Blackwood & Stins, 1880. — Tr. 



9i LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

blind to such a point persons of so great merit. And if others 
had the same interest, they woukl make use of it in much the 
same manner.] 

Ph. Every duty carries the idea of Law, and a law cannot 
be known or supposed without a legislator who has prescribed 
it, or without reward and without punishment. 

Th. [There can be natural reivards and penalties without 
a legislator ; intemperance, for example, is punished by disease. 
As this, however, does not injure all at first, I admit that there 
are few precepts to which you would necessarily be bound if 
there were not a God who leaves no crime without chastise- 
ment, no good act without reward.] 

Ph. (The ideas of a God and of a life to come must then also 
be innate. J 

TJi. [I am agreed in the sense in which I have explained 
myself.] 

Ph. But these ideas are so far from being written by nature 
in the minds of all men, that they even do not appear very clear 
and very distinct in the minds of many students, who also pro- 
fess to examine things with some accuracy ; so far are they 
from being known by every human being. 

Til. You return again to the same proposition, which main- 
tains that what is not known is Jiot innate, which I have, how- 
ever, refuted so many times. ^Vhat is innate is not at first 
.known clearly and distinctly as such; often much attention 
and method is necessary in order to its perception, the student- 
class do not always adduce it, still less every human being.^ 

§ 13. Ph. But if men can be ignorant of or call in question 
that which is innate, it is in vain for you to speak to us of in- 
nate principles, and to claim to show us their necessity ; very 
far from their being able to serve as our instructors in the truth 
and certitude of things, as is maintained, (we shall find our- 
selves, with these principles, in the same state of uncertainty 
as if they were not in us. ) 

Th. You cannot call in question all the innate principles. 
You were agreed in regard to identical propositions or the 
principle of contradiction, admitting that there are incontest- 
able principles, although you would not then recognize them 
as innate ; but it does not at all follow that everything which 



CH. II] ON HUMAN UNDERSTANDING 95 

f is innate and necessarily connected with these innate princi- 
ples, is also at first indubitably evident. V' 

Fh. No one that I know of has yet undertaken to give us an 
exact catalogue of these principles. 

Th. But has any one hitherto given us a full and exact 
catalogue of the axioms of geometry ? 

§ 15. Ph. My Lord Herbert ^ has been pleased to point out 
some of these principles, which are : 1. There is a supreme 
God. 2. He ought to be served. 3. Virtue united with piety 
is the best worship. 4. Repentance for sin is necessary. 
5. There are penalties and rewards after this life. I agree 
that these are evident truths and of such a nature that when 
w(dl explained a reasonable person can scarcely avoid giving 
tlieni his consent. But our friends say that they are very far 
from being so many innate impressions, and if these five 
])ropositions are common notions written in our souls by the 
finger of God, there are many others which we ought also to 
])ut into this class. 

Th. I agree with you, sir, for I takem.ll the necessary truths ■ 
ars innate, and I connect with them also the instinctsj But, I 
agree with you, that these five propositions are not innate prin- 
(•i})les ; for I hold that they can and ought to be proved. 

§ 18. Ph. In the third proposition, that virtue is the wor- 
ship most agreeable to God, it is not clear what is meant by 
virtue. If you understand it in the sense most commonly 
niven to the term, I mean that which passes as praiseworthy 
;u!Cording to the different opinions which prevail in different 
countries, this proposition is so far from being evident that it 
is not even true. If you call Virtue - the acts which are con- 
formed to the will of God, this will be almost idem per idem, 
and the proposition will teach us nothing of importance ; for 
it would mean only that God is pleased with that which is con- 
formed to his will. It is the same with the notion of sin in 
the fourth proposition. 

1 Lord Eilward Herbert of Clicrbury, ]581-1(;48. His Dc Vrritatr, Paris, 
1()24, lias liad coii.si(leral)I(! inHiieiice on EiikHsIi pliilcsopliical ami ridij^ious 
thouj^ht, and is of some iinjjortanee in the interpretation of tlie polemic ol 
Lock(!'s Essay. — Tr. 

'^ For an excellent hut hrief statement and discussion of the main theories of 
virtue, cf. E. G. Robinson: Friiicijdes and Practice vf Moralili/, pp. 140- 
180. — Tr. 



90 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

Th. I do not remember to have remarked that virtue is 
commonly taken as something which depends upon opinion ; 
at least, the philosophers do not make it that. It is true that 
the name of virtue depends upon the opinion of those who 
give it to different habits or actions, according as they deem 
them good or bad and use their reason ; but all are sufficient!}^ 
agreed as to the notion of virtue in general, although they dif- 
fer in its application. According to Aristotle^ and several 
others, virtue is a habit of restraining the passions by the rea- 
son, and still more, simply a habit of acting according to rea- 
son. And that cannot fail to be agreeable to him who is the 
supreme and final reason of things, to whom nothing is indif- 
ferent, and the acts of rational creatures less than all others. 

§ 20. Ph. You are wont to say that the custom, the educa- 
tion, and the general opinions of those with whom you con- 
verse may obscure these principles of morality which you 
suppose innate. But if this reply is a good one, it annihilates 
the proof which you pretend to draw from universal consent. 
The reasoning of many men reduces to this : The principles 
which men of right reason admit are innate ; we and those 
of our mind are men of right reason ; consequently our princi- 
ples are innate. A pleasant method of reasoning, which goes 
straight on to infallibility ! 

Th. For myself, I make use of universal consent, not as a 
principal proof, but as a confirmatory one ; jfor innate truths 
taken as the natural light of reason bear their marks with 
them as does geometry, for they are wrapped up in the im- 
mediate principles which you j^ourselves admit as incontesta- 
ble. I But I grant that it is more difficult to distinguish the 
instincts and some other natural habits from custom, although 
it may very often be possible so to do. For the rest, it appears 
to me that people who have cultivated their minds have some 
ground for attributing the use of right reason to themselves 
rather than to the barbarians, since in subduing them almost 
as easily as they do animals they show sufficiently their supe- 

1 Eth. Mr. II. G, ad init. Cf. Zeller: Outlines of the Hist, of Greek Philos., 
§ 61 : and E. Wallace : Outlines of the Philos. of Aristotle, M ed., § oil, pp. 97- 
90. Cambridge : University Press, ISSo. In connection with each section of 
his brief English statement and exposition, Wallace aives the Greek text of 
" the more important passages in Aristotle's writings," with references to the 
Berlin Academy edition of Aristotle. — Tr. 



CH. II] ' ON HUMAN UNDERSTANDING 97 

riority. But if they cannot always succeed in this, it is be- 
cause just like the animals they conceal themselves in the 
thick forests, where it is difficult to hunt them down and the 
game is not worth the candle. It is doubtless an advantage to 
have cultivated the mind, and if we may speak for barbarism 
as against culture, we shall also have the right to attack rea- 
son in favor of the animals, and to take seriously the witty 
sallies of M. Despreaux,^ in one of his satires, where, in order 
to contest with man his prerogative over the animals, he asks, 
whether. 

The bear is afraid of the passer-by, or the passer-by of the bear ; 
And if, by decree of the shepherds of Libya, 
The lions would vacate the parks of Numidia, etc. 

We must, however, admit that there are some points in which 
the barbarians surpass us, especially as regards vigor of body ; 
and as regards the soul even we may say that in certain respects 
their practical morality is better than ours, because they have not 
the avarice of hoarding nor the ambition of ruling. And we 
may even add that association with Christians has made them 
worse in many respects.^ They have taught them drunkenness 
(when carrying them the water of life), swearing, blasphemy, 
and other vices, which were little known to them. There is 
with us more of good and of evil than with them : a bad Euro- 
pean is worse than a savage — he refines upon evil.^ Still, 
nothing should prevent men from uniting the advantages which 
nature gives to these peoples with those which reason gives us. 

1 Nicolas Boileau-Despreaux, 10.36-1711. The passage quoted is from Sat. 8, 
62-64. The text as given by all the editions I have been able to consult, 
twelve, ranging from 1716-1873, reads thus : 

"L'ours a peur du passant, on le passant de I'ours; 
Et si, sur un edit des patres de Nubie, 
Les lions de Barca videraient la Lybie;" etc. 
Lines 63 and 64 of the text, as given by Leibnitz, editions of Gerhardt and 
Erdmann, Jacques modernizing the spelling and correcting the misplacement 
of " de " and " des " in line 63, read thus : 

" Et si par un edit de pastres des Lybie 
Les Lions vuideroient les pares de Numidie," etc. 

It seems evident tliat Leibnitz misquoted tlie lines. — Tk. 

2 Compare J. G. Schurman: The Ethical Import of Danvinisn) , pp. '2rtCi-'2G0 
as above. — Tr. 

2 The Frcncli is: " il rafine sur h; mal." — Tr. 



98 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

Ph. /But what reply do you make, sir, to this dilemma of 
one 01 my friends? I would be pleased, he says, to have the 
advocates of innate ideas tell me whether these principles can 
or cannot be effaced by education and custom. If they cannot 
be effaced Ave ought to find them in all men, and they should 
clearly appear in the mind of each particular man. If they 
can be altered by extraneous ideas, they ought to appear more 
distinctly and with more lustre the nearer they are to their 
source. I mean in children or illiterate people, upon whom 
extraneous opinions have made less impression. Let them 
take which side they please, they will clearly see, he says, that 
it is contradicted by indubitable facts and by continual expe- 
rience.^ 

Th. I am astonished that your clever friend has confounded 
ohscurity with effacement, as some in your party confound non- 
being with non-appearance. Innate ideas and truths cannot 
be effaced, but they are obscured in all men (as they are now) 
by their inclination toward the needs of the body, and oftener 
still by the occurrence of bad customs.'! These characteristics 
of the internal light would always be shining in the under- 
standing and would give fervor to the will, if the confused 
perceptions of sense did not engross our attention. It is the 
struggle of which Holy Scripture no less than ancient and 
modern philosophy speaks. 

Ph. Thus, then, we find ourselves in darkness as thick and 
in uncertainty as great as if there were no such light. 

Th. God forbid; we should have neither science nor law, 
nay, not even reason. 

§ 21, 22, etc. Ph. I hope that you will at least admit the 
force of prejudice, which often causes that to pass as natural 
which has come from the bad' instruction to which children 
have been exposed, and the bad customs which education and 
association have given them. 

Th. I admit that the excellent author whom you follow says 
some very fine things upon that subject, and which have their 
value if they are taken as they should be ; but I do not believe 
that they are opposed to the doctrine properly understood of 
nature or of innate truths. And I am confident that he will not 
extend his remarks too far ; for I am equally persuaded that 
a great many opinions pass for truths which are only the effects 



CH. ii] ON HUMAN UNDERSTANDlNa 99 



of custom and of credulity, and that there are many such opin- 
ions, too, which certain philosophers would fain account for as 
matters of prejudice, whicli are, however, grounded in right 
reason and in nature. There is as much or more ground for de- 
fending ourselves from those who through ambition oftenest 
make pretensions to innovation, than for challenging ancient im- 
pressions. And after having meditated sufficiently upon ancient 
and modern thought, I have found that the majority of the re- 
ceived doctrines may bear a good sense. So that I wish that 
sensible men would seek to satisfy their ambition by occupy- 
ing themselves rather in building and advancing than in retro- 
grading and destroying. And I desire them to resemble the 
Romans who constructed beautiful public works, rather than 
that Vandal king ' whom his mother charged to seek the de- 
struction of these grand structures, since he could not hope for 
the glory of equalling them. 

Fh. The aim of the clever class who have contended against 
innate truths has been to prevent men from handing round 
their prejudices and seeking to cover their idleness beneath 
this fair name. 

Th. We are agreed upon this point, for, very far from ap- 
proving that doubtful principles be received, I would, for my- 
self, seek even the demonstration of the axioms of Euclid, as 
some ancients also have done. And when you ask the means 
of knowing and examining innate principles, I reply, following 
what I said above, that with the exception of the instincts 
whose reason is unknown, you must try to reduce them to first 
principles, that is to say, to axioms identical or immediate by 
means of definitions, which are nothing else than a distinct 
exposition of ideas. I do not doubt even but that your friends, 
who have hitherto been opposed to innate truths, would ap- 
prove this method, which appears consonant with their princi- 
pal aim. 

1 Chrocus, who with the Sueves and Alans is sairl to have passed over the 
Rhine near MayeiK-e, and following the evil counsel of his mother, to have 
ravaged in the most friijhtfnl manner in Germany as in Gaul. The story is 
given in tlie Olironiele of Idatiiis, eliap. 62. Cf. Bouquet, Benin Gall, et 
Franc. Scriptore.'i, Tom. 2, p. 404. — Tk. 



100 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 



CHAPTER III 

OTHER COXSIDERATIOXS TOUCHIXG IXXATE PRIXCIPLES, BOTH 
SPECULATIVE AND PRACTICAL 

§ 3. Ph. You wish to reduce truths to first principles, and 
I grant you tliat if there is any such principle, it is without 
gainsa3'ing this; it is impossible for a tiling to he and not to 
be at the same time. It appears, however, difficult to maintain 
its innate character, since you must be convinced at the same 
time that the ideas of impossibility and identity are innate. 

Th. It is quite necessary that those who favor innate truths 
maintain and be convinced that these ideas are also innate, and 
I admit that I am of their opinion. (The ideas of being, of ' 
possibility of identity, are so completely innate that they 
enter into all our thoughts and reasonings, and I regard them . 
as essential to our mind ;^ but I have already said that we do 
not always pay them particular attention and that we discern 
them only with time. I have said hitherto that_^e are, so to 
speak, innate unto ourselves, and since we are beings, the being 
we is innate ) (and the knowledge of being is wrapped up in 
that knowledge which we have of ourselves.] There is some- 
thing similar in the case of other general notions. 

§ 4. Ph. If the idea of identity is natural, and conserpiently^ 
so evident and so present to the mind that we ought to recog- 
nize it from the cradle, I would be pleased to have a child of 
seven years, and even a man of seventy, tell me whether a man 
who is a creature consisting of body and soul, is the same (man) 
when his body is changed, and whether, metempsychosis sup- 
posed, Euphorbus would be the same as Pythagoras. 

Th. (1 have stated sufficiently that what is natural to us is not 
known to us as such from the cradle \ and even an idea may be 
known to us without our being able to decide at once all ques- 
tions which can be formed thereupon. It is as if some one main- 
tained that a child cannot have a knowledge of the square and 
its diagonal, because he will have difficulty in recognizing that 
the diagonal is incommensurable with the side of the square. 
As for the question itself, it appears to me demonstratively 



CH. Ill] ON HUMAN UNDERSTANDING 101 

solved by the doctrine of Monads, which I have elsewhere^ 
shown in its true light, and we shall speak more fully of this 
matter in the sequel. 

1 Cf. the Essay, without title, Gerhardt, 4, 427 sq., written at the beginning 
of KiSiJ, and referred to as " im petit discours de Metaphysique," in Leibnitz's 
letter, Feb. 1-11, 1086, to the Landgraf Ernst von Hesseu-liheiufels, (i. 2, 11. 
This ' Discours,' regarded by Leibnitz as the beginning of his philosophy, con- 
tains a summary, centring about the idea of the individual substance, of all 
his previous philosophical speculation. He gained this idea, and with it a 
seemingly satisfactory solution of the iirincipal philosophical problem, at the 
end of 1G85 or the beginning of IGSG. For this idea, still in process of devel- 
opment, possessing the elements of force and individuality, but lacking those 
of contiiuiity and perceptive activity evolved between 1086 and 1(397, Leibnitz, 
in 1()97, when the idea possessed all the elements essential to its completeness 
in his system, apjjropriated the term "monad." This term he borrowed, not 
from Giordano Bruno, 1548-1000, who used it in a similar though not precisely 
the same sense, but from Francois Mercure V'an Helmont, 1018-1099. So far 
as known, the term "monad" is first mentioned in the letter to Fardella, 
Sept. 3-13, 109(), first published by Foucher de Careil, Nouv. lettr. et opusc. de 
Leibniz, p. 328, Paris, 1857. The doctrine in substance till 1097, and thereafter 
in name, Leibnitz frequently set forth with increasing clearness and complete- 
ness in letters to his numerous corresi)ondents, and in the " Acta Eruditorum " 
and the " Journal des Savaus." Reference may be made, amoug others, to the 
following: Correspondence with Antoine Arnaukl, 1012-1094, especially the 
letter dated Venice, Mar. 23, 1()90, G. 2, 134; Erdnianu,.107; Jacques, 1,443; 
trans.. Appendix, ; the two systematic elaborations of his system of 

the y(;ar 1095, the mathematical iu the Specimen dy namicum pro adniirandis 
natursB le>/ibus, etc., Gerhardt, Leibniz, math. Schrifi., (i, 234 sq.; the meta- 
physical in the Systeme nouceau de la nature, etc., G. 4, 477; E. 124; trans., 
Appendix, ; De ipsa naturu, etc., 1098, espec. §§ 11, 12, G. 4, 504 ; E. 154 ; 

J. 1,455 (in French) ; trans., Appendix, ; Response { Replique, Erdinann) 

aux rejtexions continues dans la seconde edition dn Dictionnaire Critique de 
M. Boyle, etc., 1702, G. 4,554; E. 183; trans., Appendix, ; Letters to 

Rud. Christ. Wagner De vi aetiva corporis, June 4, 1710, G. 7, 528; E. 405; 
trans., Duncan, Fhilo.s. Wks. of Leibnitz, 190; to Bierling, Aug. 12, 1711, 
G. 7, 500; E. 077; Principes de la nature, etc., c. 1714, G. 0, .598; E. 714; 
trans., Duncan, 209; La Monadolor/ie, 1714, G. 6, 007; E. 705; trans., Duncan, 
218, F. H. H('dge, "Jour. Spec. Philos.," Vol. 1, p. 129; Letters to Des Bosses, 
G. 2, 285 sq., passim, which pre.sent most penetrating discussions of Leiluiitz's 
metaphysic and form tlie most amph; (■(mimentary on the Moundohxjie ; to De 
Voider, 1()4.'5-1709, G. 2, 139 sq., passim, proving the intimate connection of 
Leil)nitz's dynamic and metaphysic; to Bourguct, Dec. 1714, G. 3, ,575; E. 720; 
to Remond (d(! Montmort, E. 724), Fel). 11, 1715, §§ 3, 4, G. 3, 0.35; to Dangi- 
court, Sept. 171(i, Dutens, Leibnit. opera omnia, 3, 499; E. 745. Of the pieces 
cited the most important are : The Letter to Arnauld, Mar. 2.3, lOitO, the Systeme 
nonveau, the De ipsa iiatiira, the Principes de la nature, and the Mmutdo- 
lof/ie. As Leibnitz was occujjied, more or less as circumstances permitted, 
with the composition and revision of his ' N(nv Essays,' from 1700, when Coste's 
translation of Lock(!'s 'Essay' appeared, lo 1709 ;md perhaps later (rid. ante, 
p. 9 and note), jxissibly oven as late as 1714 or 1710, tiie relntivc date of com- 
position of the several pieces liei'e cited to tliat of tiie 'New l'],s.s;iy.s ' can easily 



■^102 LEIBNITZ'S CRITIQUE OF LOCKE [i!k. i 

§ G. Ph. [I see very ■n^ell that to you I should object in vain 
that the axiom which declares that the tchole is greater than its 
part is not innate, under pretext that the ideas of whole and 
part are relative, dependent upon those of number and exten- 
sion; since you would apparently maintain that there are ideas 
conditionally innate, and that those of number and extension 
are to such a degree innate.^] 

Th. You are right, and indeed I rather believe that the idea 
of extension is posterior to that of whole and part. 

§ 7. Ph. [What say you of the truth that God should be 
worshipped ; is it innate ?] 

Th. I believe that the duty of worshipping God declares that 
on occasion you ought to show that you honor him beyond 
every other object, and that this is a necessary consequence of 
the idea of him and of his existence ; which signifies with me 
that this truth is innate. 

§ 8. Ph. But the atheists seem to prove by their example 
that the idea of God is not innate. And without speaking 
of those whom the ancients have mentioned, have not entire 
nations been discovered, who have no idea of God nor of the 
terms which denote God and the soul, as at the bay of Soldania, 
in Brazil, in the Caribbee Islands, in Paraguay ? 

Th. [The late Mr. Fabricius,^ a celebrated theologian of 
Heidelberg, has made an apology for the human race in order 

be approximated. On the whole subject, cf. L. Stein, Leibniz u. Spinoza, chap. 6, 
pp. 111-219, Berlin : G. Reimer, 1890, who traces the history of the rise of the 
monad-doctrine from 1680 till all the elements of the complete conception were 
present in 1697; E. Dillmann, E. neue Bar stg. d. Leibniz. Monadenlehre auf 
Griind d. Quellen, Leipzig: O. R. Reislaud, 1891, whose monograph is an elab- 
orate discussion of the entire subject with references to or quotations from all 
the sources. — Tr. 

1 The French text is : " puisque vous soutiendres apparemraent, qu'il y a des 
idees innees respectives, et que celles des nombres et de I'etendue sont innees 
aussi." — Tr. 

- John Lewis Fabricius, lfi.32-1697. Professor, first of Greek, then of Philos- 
ophy and Theolooy, at Heidelberg. In 16(>4 he received the title of " Conseiller 
ecclesiastique de I'electeur palatin." Some years after, when Heidelberg was 
burning, he saved the archives of the church and the university, carrying 
them first to Eberbach, then to Frankfort, where he died. The title of the 
work referred to in the text (vid. ante, p. 21 also, where the name is given 
Fabritius, in accord with his own signature in the letter of Feb. Ifi, 1673, to 
Spinoza, offering him the professorship of Philosophy at Heidelberg) is: Apol- 
Of/in f/eneris humnni ronfra cfihimnicm afJiei.tmi. It ajipeared in l(i(>2. His 
collected works, with a life, were published by J. H. Heidegger, Zurich, 1698, 
in 4to. — Tk, 



ni. Ill] ON HUMAN UNDERSTANDING 103' 

to clear it of the imputation of atheism. He was an author of 
great accuracy, and decidedly above much prejudice; I do not, 
liowever, pretend to enter into this discussion of facts. I grant 
that entire peoples have never thought of the supreme sub- 
stance, nor of the nature of the soul. And I remember, that 
when you wished at my reqiiest, countenanced by the illus- 
trious Mr. Witsen, to obtain forme in Holland a translation of 
the Lord's Prayer into the language of Barantola, you were 
stopped at this point : halloived he thy name, because you 
could not make the Barantoli understand what halloived 
meant. I remember also that in the. creed made for the Hot- 
tentots you were obliged to express Holy Spirit by words of 
the country Avhicli signify a pleasant and agreeable wind.^ 
This was not unreasonable, for our Greek and Latin words 
Ti-rev/xa, anima, spiritus, mean ordinarily only the air or wind 
we breathe, as one of the most subtile things which we know 
through the senses ; and we begin through the senses to lead 
meu little by little to what is beyond the senses. All this diffi-" 
eulty, however, which you find in attaining abstract knowledge 
effects nothing against innate knowledge. There are peoples 
who have no word corresponding to the word being ; does any 
one doubt their knowledge of what being is, although they 
sf'ldom think of it in the abstract ? Besides I find what I 
have read in our excellent author on the idea of God (Essay on 
Luiderstanding, Book I., chap. 3,^ § 9) so beautiful and so to 
my liking that I cannot refrain from quoting it.^ Here it is : 
" Men can scarcely avoid having some kind of idea of things 
of which those with whom they converse often have occasion 
to speak under certain names, and' if the thing is one which 
earries Avith it the idea of excellence, of grandeur, or of some 
extraordinary quality which interests in some point and which 
impresses itself upon -the mind under the idea of an absolute 
and irresistible power which none can help fearing " (I add : 
and under the idea of a superlatively great goodness which 
none can help loving), "such an idea ought, according to all 

1 ([f. Bciok III., cliap. 1, ^ V,, Til. (2). — Tr. 

2 Cliiip. 4, ill Locke's treatise, Kolin's ed. — Tii. 

3 The Frencli ti'aiislatinii of T^ncke's orij^inal, is, in my jiuljiineiit, elearev in 
r<ir!ii of statement and style tliaii Locke liimself. ?Ieiice I have ri'translated the 
I'rench into Ennlish. If any n^ader prefers Locke's orii^inal, lie can easily find 
it iu the Philoa. Work)^, Bolin's ed., Vol. 1, p. 188. — Tii. 



104 LEIBNITZ'S CRITIQUE OF LOCKE [bk. i 

appearances, to make the strongest impression and to spread 
I'arther than any othei", especially if it is an idea which accords 
Avith the simplest insight of reason, and which flows naturally 
from every part of knowledge. Now such is the idea of God, 
for the brilliant marks of extraordinary wisdom and power 
appear so plainly in all the works of the creation, that every 
rational creature who will reflect thereupon cannot fail to dis- 
cover the author of all these marvels ; and the impression that 
the discovery of such a Being must naturally make upon the 
souls of all those who have once heard him spoken of is so great, 
and carries with it thoughts of so great weight and so adapted 
to spread themselves in the world, that it appears to me Avholly 
strange that an entire nation of men can be found upon the 
earth so stupid as to have no idea of God. This, I say, seems 
to me as surprising as to think of men who should have no 
idea of numbers or of fire." 

I would I might always be allowed to copy word for word a 
number of other excellent passages of our author, which we are 
obliged to pass by. I will only say here, that this author, in 
speaking of the simplest lights of reason, which agree with the 
idea of God, and of that which naturally proceeds from it, ap- 
pears to differ but little from my view of innate truths ; and, 
concerning this, that it appears to him as strange that there 
may be men without any idea of God, as it would be surprising 
to find men who had no idea of numbers or of fire, I will remark 
that the inhabitants of the Marian Islands, to which has been 
given the name of the Queen of Spain, who has protected mis- 
sions there, had no knowledge of fire when they were dis- 
covered, as appears from the narrative which Rev. Father 
Gobien,^ a French Jesuit, charged with the care of distant 
missions, has given to the public and sent to me.] 

§ 16. Ph. If you are right in concluding that the idea of 
God is innate, from the fact that all enlightened races have 
had this idea, virtue ought also to be innate because enlightened 
races have always had a true idea of it. 

Th. [Not virtue, but the idea of virtue, is innate, and per- 
haps you intend only that.] 

1 Charles le Gobien, 105.3-1708. Professor of Philosophy at Tours; secre- 
tai-y and procnrator of Chinese missionaries; wrote and published a number 
of works on these missions in China; his Histoire des Isles Mariannes, Paris, 
1700, 12mo. — Tr. 



CH. Ill] ON HUMAN UNDERSTANDING 105 

Ph. It is as certain that there is a God, as it is certain that 
the opposite angles made by the intersection of two straight 
lines are equal. And there has never been a rational Qreature 
who applied himself sincerely to the examination of the truth 
of these two propositions who has failed to give them his con- 
sent. Nevertheless, it is beyond doubt that there are many 
men who, having never turned their thoughts in this direction, 
are ignorant equally of these two truths. 

Th. [I admit it ; but that does not prevent them from being 
innate — that is to say, does not prevent you from being able 
to find them in yourself.] 

§ 18. Ph. It would be more advantageous to have an innate 
idea of substance ; but it turns out that we do not have it, 
either innate or acquired, since we have it neither through 
sensation nor reflection. 

Th. [I am of opinion that reflection suffices to discover 
the idea of substance within ourselves, who are substances. 
And this notion is one of the most important. But we shall 
speak of it, perhaps more fully, in the sequel of our con- 
ference.] 

§ 20.^ Ph. If there are innate ideas in the mind without the 
mind's being actually aware of their presence, they must at 
least be in the memory, whence they must be drawn by means 
of reminiscence — that is to say, be known, when memory re- 
calls them, as so many perceptions which have been in the 
mind before, unless reminiscence can subsist without reminis- 
cence. For this conviction, where it is an inwardly certain 
one, that a given idea has previously been in our mind, is 
properly what distinguishes reminiscence from every other 
kind of flunking. 

Th. [In order that knowledge, ideas, or truths be in our 
mind, it is not necessary that we have ever actually thought of 
them ; they are only natural habitudes ; i.e. dispositions and 
aptitudes, active and passive, and more than a tabula rasa. 
It is true, however, that the Platonists believed that we have 
already actually thought of that which we recognize in our- 
selves ; and to refute them it is insufficient to say that we do 
not at all remember it, for it is certain that an infinite number 

^ Gcrliardt's reading. So also Locke, Philos. Works, Vol. 1, p. 197, Bohn's 
ed. — Tr. 



lOG LEIBNITZ'S CRITIQUE OF LOCKE [i;k. i 

of thoughts recur to us which we have forgotten that we 
had. It has happened that a man believed he had composed a 
new verse, whicli it turned out he read word for word a long 
time previous in some ancient poet. And often we have an 
extraordinary facility of conceiving certain things, because we 
formerly conceived them, without remembering them. It is 
possible that a child, having become blind, forgets ever having 
seen light and colors, as happened at the age of two and a half 
years from small-pox in the case of tlie celebrated Ulric Schoen- 
berg, a native of Weide, in the Upper Palatinate, who died at 
Konigsberg, in Prussia, in 1649, where he taught philosophy 
and mathematics to the admiration of every one. It may be 
that such a man has remaining effects of former impressions 
without remembering them. I believe that dreams often thus 
revive in us former thoughts. Julius Scaliger,' having cele- 
brated in verse the illustrious men of Verona, a certain self- 
styled Brugnolus, a Bavarian by birth, but afterward estab- 
lished at Verona, appeared to him in a dream and complained 
that he had been forgotten. Julius Scaliger, not remembering 
to have heard him spoken of before, did not allow himself to 
make elegiac verses in his honor in consequence of this dream. 
At length, the son, Joseph Scaliger,^ travelling in Italy, learned 
more particularly that there had been formerly at Verona a 
celebrated grammarian or learned critic of this name, who had 
contributed to the re-establishment of polite literature in Italy. 
This story is found in the poems of Scaliger the father, to- 
gether with the elegy, and in the letters of the son. It is 
related also in the " Scaligerana," ^ which are culled from the 

1 .Julius CiEsai- Scaliger, 14S4-155S. His Latin verse appeared in successive 
volumes in 1533, 1534, 1539, 1546, 1574. His tastes were, however, philosophi- 
cal and scientific rather than literary. His scientific works, in the form of 
commentaries, have only a historical interest. The Exotericarum exerciiatio- 
num lihi'r, Paris, 1557, 4to, a philosophical treatise on the De Siihtilitate, 1552, 
of Cardan {vid. ante, p. 67, note 1), is the work which best makes known 
Scaliger as a philosopher. It was a popular text-book until the final fall of 
Aristotle's physics. — Tr. 

2 Joseph Justus Scalioer, 1540-1609, reputed the greatest scholar of modern 
times. He was the first to set forth and apply sound principles of textual 
criticism and emendation in his editions of some of the classical authors, and 
with him arose a new school of historical criticism. He reconstructed the lost 
Chronicle of Eusebius, a work of considerable importance in the study of 
ancient history. — Tr. 

3 Two collections of anecdotes concerning Joseph Scaliger, numbered accord- 



, ir. in] ON HUMAN UNDERSTANDING 107 

conversations of Joseph Scaliger. It is very likely that Julins 
Sealiger had known something of Brugnol which he no longer 
remembered, and that the dream was partly the revival of a 
former idea, although he may not have had that reminiscence, 
properly so called, which makes us know that we have already 
had this same idea ; at least, I see no necessity which obliges 
us to assert that there remains no trace of a perception when 
there is not enough of it to remind us that we have had it.] 

§ 24. Ph. [I must admit that your reply is natural enough 
to the difficulties Avhich we have framed against innate truths. 
I'erhaps, also, our authors do not contest them in the sense in 
which you maintain them. Thus I return only to say to you, sir] 
that we have had some reason to fear that the view of innate 
truths serves as a pretext for laziness, for exempting ourselves 
from the trouble of research, and gives opportunity to masters 
and teachers to lay down as a principle of p?v'?;c/^)?c.s that 
]»rinciples must not be questioned. 

Th. [I have already said that if it is the aim of your friends 
to advise the search for the proofs of the truths which 
tliey can receive, without distinguishing whether or not they 
are innate, we are entirely agreed ; and the view of innate 
truths, of the manner in which I take them, should deter no one 
from such search, for, besides being well to seek the reason of 
the i)istincts, it is one of my great maxims that it is good to 
seek demonstrations of the axioms also, and I remember that 
at Paris, when the late Mr. Koberval,' already an old man, was 

ini,' to their date of composition. The first was written in Latin l)y Franrois 
\'i rtunien, a friend of Sealiger, who took notes of iiis conversations with 
Scaliiicr, especially of all criticisms or anecdotes worthy of preservation, and 
iiltrrwards wrote them out. An advocate, Fran(,>ois de Sigogne, l)ought tiie 
MS. long after the author's death, and i)ulilished it at Haunier in l<!(i9. The 
second was written in French and Latin by two youths named Vassan, who, 
when students at Leyden, habitually conversed after supper with Sealiger, then 
I'rofessor of Belles Lettres there, and on their return to their rooms wrote out 
:ill tliey could remember of his conversation. Their MS. was finally published 
:ii La Haye, lOGG, by Isaac Vossius. The edition of the Sralif/ci-aua, accounted 
the best, is that of 1740, 12mo. The story is told at length, and the Elegy of 
the elder Sealiger cited, in the Cologne ed. of the Sadiqerana, 1095, pp. 69- 
7L — Tr. 

' Gilles Persoinie dc^ Roberval, a French geometer, born 1()02, at Robcrval, a 
small village of Beauvais.died 1075 at Paris. He was Proff^ssor of Mathematics 
in the Royal College of France for many years. One; of tiie conditions of the 
liMHirc of this chair was that its holder should propose niathcjuntical (picstions 
for solulion, and resign in favor of any one solving thcni better than liiinsclf. 



108 LEIIJNITZ'8 CUITIQUE OF LOCKE [bk. i 

laughed at because he wished to demonstrate those of Euclid 
after the example of A[)ollonius ' and Proclus,- 1 illustrated the 
utility of this investigation. As for the principle of those 
who say that it is wholly unnecessary to argue against the one 
who denies principles, it has no authority whatever in regard to 
these principles which can admit neither doubt uor proof. It 
is true that, in order to avoid scandal and disturbance, regula- 
tions may be made regarding public disputations and some 
other lectures, in virtue of which the discussion of certain 
established truths may be prolaibited. But this is rather a 
question of police than of philosophy.] 

Roberval kept the chair till his death. He is best known for his original 
method for the construction of tangents. — Tr. 

1 Apollonius of Perga, born probably about 250 B.C., died in the reign of 
Ptolemy Philopater, 222-205 B.C. Next to Archimedes, he was the most noted 
of the Greek geometers. His fame has been transmitted to modern times 
chiefly by his treatise on the Conic Sections, the best edition of which, and the 
only one containing tlie Greek text that has yet appeared, is : Apollonii 
perr/aei (■onicorum lihri oclo, etc., ed. Halley : O.xford, 1710, folio. He was the 
first to show that all three of the conic sections can be cut from tlie same cone 
by changing the position of the intersecting plane. — Te. 

2 Proclus Diadochus, 410^85, " the great schoolman of Neo-Platonism," the 
doctrines of which received at his hands the final form in which they have 
come down to us. He came to Athens in his twentieth year, and remained 
there teaching and writing till his death. Among his writings now extant are 
a Treatise on the Sphere, Commentaries on Euclid, and on several of Plato's 
dialogues, and the wholly independent works ^Toixe'wt^i? eeoAoyiKj, or Institutes 
of Theolof/y, and the six books ^'5 Tr)v OAaxwio? ©eoAoyiar, or Platonic Theolor/ff. 
His philosophical work is found for the most part in the Commentaries on Plato. 
For his mathematical work, cf. In primum EurUdis Elementorum lihrum 
Commentarii, e.K recognitione G. Friedlein : Lipsiae, 1873 ; also George Johnston 
Allman, Groek Geometry from Thales to Euclid, Dublin: University Press, 
18S9; and in " Hermathena," a series of papers on literature, science, and phi- 
losophy, liy members of Trinity College, Dublin, Nos. 5, 7, lO-lo, Dublin: 187S, 
1881, 1884-1887. For his philosophy, c/'- Zeller, Die Philos. d. Griech., 3d ed., 
1881, Vol.3, pp.774 sq., and Outlines,^ 101; Hegel, Gesch. d. Philos., 2d ed., 
Vol. 3, pp. 61-79; Alfred William Benn, The Greek Philosophers, Vol.2, pp. 
358-360, London: Kegan Paul, Trench, & Co., 1882. The Philosophical and 
Mathematical Cotnmentaries on. the First Bonk of Euclid's Elements, etc., 
were translated by Thomas Taylor, London, 1792, 2 vols, iu 1, 4to. — Tr. 



NEW ESSAYS ON HUMAN UNDERSTANDING 



Book II. — Ideas 
CHAPTEE I 

WHICH TREATS OF IDEAS IN" GENERAL, AND EXAMINES BY THE 
WAY WHETHER THE MIND OF MAN ALWAYS THINKS 

§ 1. Ph. Having examined the question of innate ideas, let 
us consider their nature and their differences. Is it not true 
that the idea is the object of thought ? 

Th. [I admit it, provided you add that it is an immediate 
internal object, and that this object is an expression of the na- 
ture or the qualities of things. If the idea were the form of 
thought, it would spring up and cease with the actual thought 
to which it corresponds ; but being the object it may exist pre- 
vious to and after the thoughts. External sensible objects are 
only mediate because they cannot act immediately upon the 
soul.^ God alone is the external immediate object. We might 
say that the soul itself is its own immediate internal object ; 
but it is this in so far as it contains ideas, or what corresponds 
to tilings. For the soul is a little world,^ in which distinct 
ideas are a representation of God, and in which confused ideas 
are a representation of the universe.] 

§ 2. Ph. We who suppose that at the beginning the soul is a 
tabula rasa, void of all characters and without an idea, ask how 
it comes to receive ideas, and by what means it ac(piires this 

1 Cf. Book IV., chaps. 9 and 11. The opposition liere set up botwoen mediate 
and ininiiMliate knowledge corresponds to Kant's a 2)osteriun and a priori 
knowledge. — Tk. 

2 Microcosm. — Tr. 

109 



110 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

prodigious quantity of them ? To that question the reply in a 
Avord is : From experience. 

Th. [This fabuln rasa, of which so much is said, is in my 
opinion only a fiction which nature does not admit, and which 
is based only upon the imperfect notions of philosophers, like 
the vacuum, atoms, and rest, absolute or relative, of two 
parts of a whole, or like the primary matter^' which is con- 
ceived as without form. Uniform things and those which con- 
tain no variet}^ are never anything but abstractions, like time, 
i space, and the other entities of pure mathematics. There is no 
body whatever whose parts are at rest, and there is no sub- 
stance whatever that has nothing by which "tondtstinguish it 
from every other. Human souls differ, not only from other 
souls, but also among themselves, although the difference is 
not at all of the kind called specific. And, according to the 
proofs which I believe we have, every substantial thing, be it 
soul or body, has its own characteristic relation to every other ; 
and the one must always differ from the other by intrinsic 

-■ connotations. Xot to mention the fact that those who speak 

- . so frequently of this tabula rasa after having taken away the 
• ideas cannot say what remains, like the scholastic philoso- 
phers, who leave nothing in their primary matter.^ You 
may perhaps reply that this tabula rasa of the philosophers 
means that the soul has by nature and originally only bare fac- 

- ulties. But faculties without some act, in a word the pure 
powers of the school, are also only fictions, which nature 
knows not, and which are obtained only by the process of ab- 
straction. For where in the world will you ever find a faculty 
which shuts itself up in the power alone without performing 

r any^act? There is always a particular disposition to action, 
and to one action rather than to another. And besides the 
disposition there is a tendency to action, of which tendencies 
there is always an infinity in each subject at once ; and these 
y tendencies are never without some effect. Experience is nec- 
j essary, I admit, in order that the soul be determined to such 
or such thoughts, and in order that it take notice of the ideas 

*■' which are in us; but by what means can experience and the 
senses give ideas ? Has the soul windows, does it resemble 
tablets, is it like wax ? It is plain that all who so regard the 
1 Materia Prima. — Te. 



CH. i] ON HUMAN UNDERSTANDING 111 

soul, represent it as at bottom corporeal. You oppose to me this 
axiom received by the philosophers, that there is nothuig in the 
soul which does not come from the senses. But you must except 
the soul itself aud its affections. Nihil est in intellectu, quod 
non fiierit in seiisu, excipe : nisi ipse intellectus. Now the soul 
comprises being, substance, unity, identity, cause, perception, • 
reason, and many other notions which the senses cannot give. 
This view sufficiently agrees with your author of the Essay, who 
seeks the source of a good part of ideas in the spirit's reflec- 
tion upon its own nature. 

Ph. [I hope, then, that you will agree with this skilful 
author that all ideas come through sensation or through re- 
flection, that is to say, from observations which we make either 
upon objects exterior and sensible or upon the inner workings 
of our soul. 

Th. [In order to avoid a discussion upon what has delayed 
us too long, I declare to you in advance, sir, that when you 
say that ideas come to us from one or the other of these causes, 
I understand the statement to mean their actual perception, 
for I think I have shown that they are in us before they are 
perceived so far as they have any distinct character. 

§ 9. Ph. [In the next place let us inquire when we must 
say that the soul- begins to perceive and actually to think of 
ideas. I well know that there is an opinion which states that 
the soul always thinks, and that actual thought is as inseparable 
from the soul as actual extension is from the body. § 10. But 
I cannot conceive that it is any more necessary for the soul 
always to think than for the body always to be in motion, per- 
ception of ideas being to the soul what movement is to the 
body. That appears to me very reasonable at least, and I 
would gladly know your vieAv, sir, thereupon. 

Th. You have stated it, sir. Action is no more connected 
with the soul than with the body, a state without thought in 
the soul and an absolute repose in the body appearing to me 
equally contrary to nature, and without example in the world. 
A substance once in action, will be so always, for all the im- 
pressions remain and are merely mingled with other new ones. 
Striking a body, we arouse therein or determine rather an 
infinite number of vortices as in a liquid, for at bottom every 
solid has a degree of liquidity and every liquid a degree of 



112 LEIBNITZ'S CRITIQUE OF LOCKE [hk. ii 

solidity, and there are no means of ever stopping entirely these 
internal vortices. Now we may believe that if the body is 
never at rest, the soiil, which corresponds to it, will never be 
without perception either.] 

Ph. But it is, perhaps, a privilege of the author and conserver 
of all things, that being infinite in his perfections, he never slum- 
bers nor sleeps. This is not granted to any finite being, or at 
least not to such a being as is the soul of man. 

Th. [It is certain that we slumber and sleep, and that God 
is exempt from both. But it does not follow that we have no 
perception while asleep. Rather just the contrary is found to 
be the case, if we consider it carefully.] 

Ph. There is something in us which ha^ the power to think ; 
[but it does not thereby follow that it is always in action.] 

Th. [Real powers are never simple possibilities. They have 
always tendency and action. 

Ph. But this proposition — the soul always thinks — is not 
self-evident. 

Th. I do not say it is. A little attention and reasoning is 
necessary to discover it ; the common people perceive it as little 
as they do the pressure of the air or the roundness of the earth.] 

Ph. I doubt if I thought last night ; this is a question of fact, 
it must be decided by sensible experiences. 

Th. [It is decided as it is proved, that there are imperceptible 
bodies and invisible movements, although certain persons treat 
them as absurd. There are also numberless perceptions little 
noticed which are not sufficiently distinguished to be perceived 
or remembered, but they become known through certain conse- 
quences.] 

Ph. There was a certain author who raised the objection that 
we maintain that the soul ceases to exist, because we are not 
sensible of its existence during our sleep. But this objection 
can arise only from a strange prepossession, for we do not say 
that there is no soul in man because we are not sensible of its 
existence during our sleep, but only that man cannot think 
without being aware of it. 

Th. [I have not read the book which contains this objection, 
but it would not have been wrong merely to object to you that 
it does not follow because the thought is not perceived, that it 
ceases for that reason ; for otherwise it could be said for the 



CH. I] ON HUMAN UNDERSTANDING 113 

same reason that there is no soul during the time in which it 
is not perceived. And to refute this objection it is necessary 
to point out in particular the thought that it is essential to it 
that it be perceived.] 

§ 11. Ph. It is not easy to conceive that a thing can think 
and not be conscious that it thinks. 

Th. There is, doubtless, the knot of the affair and the diffi- 
culty which has embarrassed able men. But here are the means 
of extricating ourselves therefrom. We must consider that we 
think of many things at a time, but we attend only to the 
thoughts whicji_are most distinct, and the process cannot go 
'oiFoTherwise, for il^ we should attend to all, we would have to 
thinE"attentively of an infinite numl)cr of things at tlic same 
time, all of which we feel and whicli make an impression upon 
""our senses: i'My^eveiTmoi^T'tTiere remains sometlnng of all 
our past thoughts, and none can ever be wholly effaced. Now 
when we sleep without dreaming and when we are stunned by 
some blow, fall, symptom, or other accident, an infinite number 
of minute confused sensations take form within us, and death 
itself canprodriceTro other effect upon the souls of animals, 
who ought, doubtless, sooner or later, to acquire distinct per- 
ceptions, for all goes on in an orderly way in nature. I admit, 
however, that in this state of confusion, the soul would be with- 
out pleasure and Avithout pain, for these are noticeable percep- 
tions. 

§ 12. Ph. Is it not true that those with whom Ave have at 
present to do, \_i.e. the Cartesians, who believe that the soul 
always thinks,] grant life to all animals, differing from man, 
without giving them a soul which knows and thinks ; and that 
these same (Cartesians) find no difficulty in saying that the soul 
can think independently of a body ? 

Th. [For myself, I, am of another opinion, for although T 
agree with the Cartesians in their affirmation that tin; soul 
thinks always, I am not agreed with them in the two other 
points. I believe that the beasts have imperishable souls and 
that human and all other souls are never without some body. 
I hold also that God alone, as being an actxcs purus, is wholly 
exempt therefrom.] 

Ph. If you had been of the 0]union of the C!artosiaiis, 1 sliouhl 
have inferred therefrom, that tlu; bodies of Castor or Tollux 
I 



114 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

could be sometimes with, sometimes without a soul, though 
being always alive, and the soul having the ability also to be 
sometimes in one body and sometimes elsewhere, we might 
suppose that Castor and Pollux had only a single soul, which 
was active alternately in the body of these two men sleeping 
and awake by turns ; thus it would be two persons as distinct 
as Castor and Pollux could be. 

Th. I, in my turn, will make you another supposition, 
which appears more real. Is it not true that we must always 
admit that after some interval or some great change, one may 
fall into a state of general forgetfulness ? Sleidan ^ (they say), 
before his death, forgot all he knew ; and there are many 
other examples of this sad event. Suppose that such a man 
became young again and learned all anew, will he be another 
man on that account ? It is not then memory which, properly 
speaking, makes the same man. Kevertheless, the fiction of a 
soul which animates different bodies in turn, without concern- 
ing itself in one of these bodies with that which happens to it 
in the other, is one of those fictions contrary to the nature of 
things which arise from the imperfect notions of philosophers, 
as space without body and body without motion, and which dis- 
appear when one penetrates a little deeper ; for you must know 

1 John Sleidan, original name Philipsohn, e. 150G-1556, the annalist of the 
Reformation. He was secretary for five years from 153() to Cardinal du Bellay, 
minister of Francis I. of France. He was wont to copy all documents bearing 
upon the Reformation to which he had access, and upon the suggestion of 
Bucer to Philip of Hesse, after some delay was appointed, with the consent 
of the heads of the Sehmalkaldic League, historian of the Reformation, with a 
salary and access to all necessary documents. He finislied the first volume of 
his great work in 1545. His work was then interrupted by a diplomatic mis- 
sion in a French embassy to Henry VIII. of England. While there he improved 
every opportunity to collect materials for his history. In 1551 he was a mem- 
ber of the Council of Trent for Strassburg. On his return he was made Pro- 
fessor of Law at Strassburg, a position which enabled him to devote his whole 
attention to his great work. It was finished for the press in 1554, and published 
at Strassburg in 1555. It is entitled : Commentariorum de statu relif/ioiiis et 
rcipublicx C'arolo Quinto, Csesare, libri XXVI. The ed. of 1555 contained 
only 25 books ; that of 1559 the 2Gth and an apology of Sleidan, written by 
himself. The best edition is that of Francfort, 1785-8G, 3 vols., 8vo. The work 
is "the most valuable contemporary history of the times of the reformation, 
and contains the largest collection of important documents." It is especially 
notewortliy for its accuracy, impartiality, and purity of style. There are two 
English translations, by John Daws, 1560, and G. Bohum, 1680. There are 
also translations in other languages. Cf. H. Baumgarten, Ufher Sleidanus 
Leben und Briefwechsel, 1878 ; Sleidans Briefwechsel, 1881. — Tr. 



CH. I] ON HUMAN UNDERSTANDING 115 

that each soul preserves all its preceding impressions, and 
cannot divide itself equally in the manner just mentioned; the 
future in each substance is perfectly united to the past ; this 
is what constitutes the identity of the individual. Memory, 
furthermore, is not necessary, nor even always possible, because 
of the multitude of present and past impressions which co-op- 
erate in our present thoughts, for I do not believe that there 
are in man thoughts of which there is not some effect at least 
confused or some remnant mixed with subsequent thoughts. We 
can forget many things, but we could also remember them long 
after if we would recall them as we ought. 
/ § 13. Ph. Those who chance to sleep without dreaming can 
never be convinced that their thoughts are active. 

Th. [One is feebly conscious in sleep, even when it is dream- 
less. The process of waKTngup itself shows this, and the easier 
you are awakened the more~you "are conscTous of what goes on 
without, although this consciousness is not always strong enough 
to cause you to awake.] 

§ 14. Ph. It appears very difficult to conceive that the soul 
is thinking at this moment in a sleeping man and the next in 
one awake, without remembering its thoughts. 

Th. [ISTot only is that easy to conceive, but also something 
like it is observed every day that we are awake ; for we always 
have objects which strike our eyes and ears, and, as a result, 
the soul is touched also, without our taking notice of it, because 
our attention is bent upon other objects, until this object becomes 
strong enough to draw it to itself, by redoubling its action or by 
some other means ; it is like a particular sleep with reference 
to that object, and this sleep becomes general when our atten- 
tion ceases to regard all objects together. Division of attention, 
in order to weaken it, is also a means of putting yourself to sleep.] 

Ph. I learned from a man, who in his youth had applied him- 
self to study and had a tolerably felicitous memory, that he 
never had a dream until he had had the fever, from which he 
had just recovered at the time he spoke Avith me, at the age of 
twenty-five or twenty-six years. 

Th. [I have also been told of a student, more advanced in 
years, who never had a dream. But it is not upon dreams alone 
that you must base the perpetuity of the soul's perception, since 
r have shown how, even while asleep, it has some perception of 
what goes on without.] 



IKi LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

§ 15. Ph. To think frequently and not to preserve a single 
moment the memory of your thought, is to think in a useless 
manner. 

Til. [All impressions have their effect, but all the effects are 
not always perceptible ; when I turn to one side rather than to 
the other, it is very often through a series of minuteim pi-essio ns 
of which I am not conscious, and which render one movem ent 
a littlSTSore uncomfortable than the other. All our unpre- 
meditated actions are the results of a concurrence of minute 
perceptions, and even our customs and passions, which influ- 
ence so much our deliberations, come therefrom; for these 
habits grow little by little, and, consequently, without the 
minute perceptions, we should not arrive at these noticeable dis- 
positions. I have already remarked that he who would deny 
these effects in the sphere of morals, would imitate the poorly 
taught class who deny insensible corpuscles in physics ; and 
3'et I see that among those who speak of liberty are some who, 
taking no notice of these unperceived impressions, capable of 
inclining the balance, imagine an entire indifference in moral 
actions, like that of the ass of Buridan ^ equally divided between 
two meadows. Concerning this we shall speak more fully 
later. I admit, however, that these impressions incline with- 
out necessitating. 

Ph. Perhaps we might say that in the case of a man awake 
who thinks, his body counts for something and that memory 
is preserved by means of marks in the brain, but w4ien he is 
asleep the soul thinks apart by itself. 

1 John Buridan, a celebrated Nominalist of the 14th century, the date of 
whose birth and death is unknown. He studied at Paris under William of 
Occam (died 1.347) and was for many years Professor of Philosophy in the 
University of Paris, and in 1327 its rector. In philosophy his only authority 
was reason. In the third book, first question, of Iiis Quiestiones hi decern libros 
ethicorum Aristotelis, 1489, he discussed in an "independent and interesting 
manner " the question of the freedom of the will, reaching conclusions similar 
to those of Locke. In his view the liberty possessed by the soul consists in 
" a certain power of suspending the deliberative process, and determining the 
direction of the intellect; otherwise the will is entirely dependent on the view 
of the mind, the last result of examination." The story of the ass as an illus- 
tration of the indeterminisra of the will "is not," as Sir William Hamilton 
says (Reid, 8th ed., Vol. 1, p. 238, note) he has ascertained, " to be found in 
his writings." On Buridan, cf. Ueberweg, Hist, of Philos., English transla- 
tion, "Vol. i, pp. 4G5-4(JtJ; Prautl, Gesch. d. Logik, Yol.i, 14-38; Stockl, Gesch. 
d. Philos, d. Mittelalters, Vol. 2, 1023-1028. — Tb. 



CH.'i] ON HUMAN UNDERSTANDING 117 

Th. I am very far from saying tliat, since I believe there 
is always an exact correspondence between the body and 
the soul, and since I employ the impressions of the body 
of which we are not conscious, whether awake or ^asleep, in 
oMerTojDiXLve Jhat, the, soul has. in itself similar ones. I 
maintain even that something goes on in the soul which cor- 
responds to the circulation of the blood and to all the internal 
movements of the viscera, of which we are never conscious 
however, just as those who live near a water-mill do not per- 
ceive the noise it makes. In fact, if there were impressions 
in the body during sleep o-r waking hours, by which the soul 
was not touched or in any wise affected, limits would be given 
to the union of the soul and of the body, as if corporeal 
impressions required a certain form and size in order for the 
: soul to perceive them ; which is not at all tenable if the soul 
is incorporeal, for there is no relation between an incorporeal 
substance and this or that modification of matter. In a 
word, it is a great source of error to believe that there is no 
perception in the soul besides those of which it is con- 
scious. 

§ IG. Ph. The greater part of the dreams which we remem- 
ber are extravagant and incoherent. We should then say that 
the soul owes the power of rational thought to the body, or 
that it retains none of its rational soliloquies. 

Th. [The body responds to all the soul's thoughts, rational 
or not, and dreams have also their marks in the brain as well 
as the thoughts of those who are awake. 

§ 17. Ph. Since you are so sure that the sovil is always 
actually thinking, I wish you would- tell me what the ideas 
are which are in the child's soul before it is united to the body, 
ox just at the time of its union, before it has received any idea 
by means of sensation. 

Th. It is easy to satisfy you by our principles. The soul's 
perceptions correspond always naturally to the constitution of 
the body, and whert there are a multitude of movements con- 
fused and little distinguished in the brain, as happens in the 
case of those who have little experience, the soul's thoughts 
(following the order of the things) cannot be move distinct. Yet 
the soul is never dei)riv(!d of the help of soirsiition, because it 
always expresses its body, and tliis body is always impressed 



118 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

by its surroundings ^ in an infinite number of ways, but which 
often give only a confused impression. 

§ 18. Ph. Bur^here'is still another question Avhich the 
author of this Essay asks. I very much wish (says he) that 
those who maintain so confidently that the soul of man or 
(what is the same thing) man thinks always, would tell me 
how they know it ? 

Th. [I do not knoAv but that more confidence is necessary to 
deny that anything goes on in the soul of which we are not 
conscious ; for that which is perceivable must be composed of 
parts which are not so, nothing can spring into being at once, 
thought no more than motion. In short, it is as if some one 
asked to-day how we know the insensible corpuscles. 

§ 19. Pli. I do not remember that those who tell us that 
the soul always thinks ever say that man always thinks. 

Th. [I think that is because they understand their state- 
ment of the separated soul, and yet they voluntarily admit that 
man always thinks during the union. For myself, who have 
reasons for holding that the soul is never separated from the 
entire body, I believe that we can state absolutely that man 
always does and will think.] 

Ph. To say that the body is extended without having parts, 
and that a thing thinks without being conscious that it thinks, 
are two assertions which appear equally unintelligible. 

Th. [Pardon me, sir; I am obliged to tell you that when 
you advance the statement that there is nothing in the soul of 
which it is not conscious, you beg the question which has al- 
ready prevailed in all our former discussion, or you have been 
desirous to use it to destroy innate ideas and truths. If we 
agree to this principle, in addition to the fact that we believe 
it contrary to experience and reason, we should surrender with- 
out reason to our feeling, which, I believe, I have rendered 
sufficiently intelligible. But besides the fact that our oppo- 
nents, skilful as they are, have brought no proof of that which 
they urge so often and so positively, it is easy to show them 
the contrary ; i.e. that it is impossible for us always to think 

1 Gerhardt reads: " frappe paries ambians d'une infinite de manieres, niais 
qui soiiveut ne donnent qu'une impression confuse." Erdmann and Jacques 
read: "frappe par les autres, qui renvironnent, d'une infinite de manieres, 
mais qui souvent ne font qu'une impression confuse." — Tr. 



CH. I] ON HUMAN UNDERSTANDING 119 

expressly upon all our thoughts ; otherwise, the spirit would 
reflect upon^each reflection to infinity without ever being able 
to pass to a new thoughtr^ For example, in my consciousness 
of some present feeling, I should always think that I think, 
and still think that I think of my thought, and thus to infinity. 
But it is very necessary that I cease reflecting upon all these 
reflections, and that there be at length some thought which is 
1 1 allowed to pass without thinking of it; otherwise, we should 
dwell always upon the same thing.] 

Ph. But would there not be as good ground for maintaining 
that a man is always hungry, by saying that he can be hungry 
I j without feeling it ? 

Th. There is just the difference ; hunger has particular rea- 
sons which do not always exist. Nevertheless, it is true also 
that even when you are hungry you do not think of it every 
moment ; but when you do think of it you feel it, for it is a 
very marked disposition ; there is always irritation in the 
stomach, but it is necessary for it to become very strong to 
cause hunger. The same distinction ought always to be made 
between thoughts in general and remarkable thoughts. Thus, 
what appears to put a ridiculous construction upon our opinion, 

* serves to confirm it.] 

' § 23. Ph. One can now ask, when man begins to have ideas 
in his thought ? And it seems to me that the reply must be, 

I when he has some sensation. 

I Th. [I am of the same opinion; but it is by a principle a 

I little peculiar, for I believe that we are never without thoughts, 
and also never without sensation. I distinguish only between 
ideas ^ and thoughts ; for we always have all pure or distinct 
ideas independently of the senses ; but thoughts always corre- 
spond to some sensation.] 

§ 25. But the mind is passive only in the perception of 
simple ideas, which are the rudiments or materials of knowl- 
edge, while it is active when it forms complex ideas. 

Th. [How can it be that the mind is passive merely with 
regard to the perception of all simple ideas, since, accord- 
ing to your own admission, there are simple ideas whose per- 

1 Gcrhardt roads: "Je distingue seulement entro, Ics idw'S et los ponsecs"; 
l^rdinaiin and Jacques read: "Je distingue seulement entrc sensations et 
pense'es." — Tk. 



120 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

ception comes from reflection, and since the mind ^ gives itself 
thoughts from reflection, for it is itself which reflects ? 
Whether it can refuse them is another question, and doubtless 
it cannot (refuse them) without some reason, which turns it 
aside from them, when there is some occasion for it.] 

Ph. [It seems that hitherto we have discussed ex professo. 
Now that we are going to come to the detail of ideas, I hope 
that we shall be more agreed, and that we shall differ only in 
some particulars.] 

Th. [I shall be delighted to see able men adopting the 
views which I hold to be true, for they are adapted to improve 
them and to show them in a good light.] 



CHAPTER II 

SIMPLE IDEAS 

§ 1. Ph. I hope then that you will admit that there are 
simple and complex ideas ; thus heat and softness in wax, and 
cold in ice, furnish simple ideas, for the soul has a uniform 
conception of them, which is not distinguishable into different 
ideas. 

Th. [I believe that we can affirm that these sense-ideas are 
simple in appearance, because, being confused, they do not give 
the mind the means of distinguishing their contents. In like 
manner distant things appear round, because their angles can- 
not be discerned, although some confused impression of them 
is received. It is manifest, for example, that green arises 
from a mixture of blue and yellow ; thus it is possible to 
believe that the idea of green is also composed of these two 
ideas. And yet the idea of green appears to us as simple as 
that of blue or that of warmth. So we are to believe that the 
ideas of blue and warmth are not as simple as they appear. I 
readily consent, however, to treat these ideas as simple ideas, 
because at least our apperception does not divide them, but it 

1 Gerbardt reads : " et que I'esprit se donne " ; Erdmann and Jacques read; 
"et qu'au moins I'esprit se donne," and since the mind at least gives itself. 
— Tr. 



CH. Ill] ON HUMAN UNDERSTANDING 121 

is necessaiy to proceed to their analysis by means of other 
experiences and by reason, in proportion as they can be ren- 
dered more intelligible.^ And it is also seen thereby that 
there are perceptions of which we are not conscious, ^ov the 
perceptions of ideas simple in appearance are composed of per- 
ceptTons of the" parts~or which these ideas are composed, with- 
out the mind's being conscious of them, for these confused ideas 
appear simple to it.] ~"^ 

CHAPTER III 

! OF IDEAS WHICH COME TO US BY ONE SENSE ONLY 

i Fh. Now we can arrange simple ideas according to the 

' means by which we perceive them, for that is done, 1, by 

means of one sense only; 2, by means of more than one sense; 

,'!, by reflection, or 4, by all the ways ^ of sensation as well as 

by reflection. Thus of those which enter by a single sense 

I which is particularly adapted to receive them, light and colors 

I enter only by the eyes ; all kinds of noises, sounds, and tones 

\ enter by the ears ; the different tastes by the palate ; and odors 

' by the nose. These organs or nerves carry them to the brain, 

and if any one of these organs chance to be disordered, these 

si'iisations cannot be admitted by any artificial gate. The 

I most considerable qualities belonging to the touch are cold, 

1 heat, and solidity. The others consist either in the configura- 

( tion of the sensible parts, as smooth and rough, or in their 

i union, as compact, hard, soft, brittle.^ 

Th. [I quite agree, sir, with what you say, although I may 

ii-mark that, according to the experiment of the late M. 

! Aiariotte * upon the defect of vision with regard to the optic 

I 1 Errlmann's and Jacques's texts of chap. 2 end here; Gerhardt's text adds 
the following: " Et Ton voit encor par la qu'il y a dcs perceptions dont on ne 
s'apperooit point. Car les perceptions des idces simples en ai:)parence sont 
composocs des perceptions des parties dont ces idecs sont coniposees, sans que 
I'esprit s'en appercoive, car cesidees confuscis Iny ])aroiss('nt simples." — Tr. 

2 Locke's expression. Philos. Works, Vol. 1, p. 227, Bolin's cd. — Tr. 

8 Locke uses these forms, instead of the more common abstract forms end- 
ing in -ness. Hence I have used them in the translation. — Tr. 

* Edme Mariotte, a celebrated French physicist, born about 1(120, died 1(184. 
He was in some sense the initiator of experimental physic^s in France. The 
experiment here referred to, and the resulting discovery of the ))lind spot at 



10.J LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



nerve, it seems to me that the membranes receive the sensa- 
tion rather than the nerves, and there is an irregular en- 
trance for the hearing and the taste, since the teeth and the 
vertex assist in causing any sound to be heard, and that tastes 
make themselves known to some extent through the nose, by 
reason of the connection of these organs. But all that makes 
no change in the foundation of things as regards the explica- 
tion of ideas. As for the qualities belonging to touch, you 
can say that smoothness or roughness, hardness or softness, 
are only modifications of resistance or solidity.] 



CHAPTER IV 

OF SOLIDITY 

§ 1. Ph. You will doubtless agree that the idea of solidity 
is caused by the resistance w^e find in a body to the en- 
trance of another body into the place it occupies until it has 
left it. That which thus hinders the approach of two bodies 
when they are moved one toward another I call solidity. If 
any one finds it more to the purpose to call it imjjenetrability, I 
give my consent. But I believe that the term solidity bears 
a more positive character. This idea seems most intimately 
connected with and essential to body, and can be found only 
in matter. 

TJi. It is true that we find resistance in touch, when another 
body reluctantl}- gives place to our own, and it is also true 
that bodies dislike to occupy the same place. IManj^, how- 
ever, doubt whether this repugnance is invincible, and it is well 
also to consider that the resistance which is found in matter is 
derived in more than one way and by means of reasons quite 
different. A body resists another either when it must leave 
the place which it has already occupied, or w^hen it fails to 
enter the place into which it was ready to enter, because the 
other tries to enter also, in which case it may happen that, the 
one not yielding to the other, they stop or mutually repel each 

the entrance of the optic nerve, was made in 1G68. An account of it is given 
in a short paper in the second volume of his collected works. CEuvres de 
Mariotte, 2 vols., Leyden: 1717, 4to. — Tr. 



HI. IV] ON HUMAN UNDERSTANDING 123 

other. The resistance is seen in the' change of that (body) to 
which resistance is offered, whether it loses its force, changes 
its direction, or both happen at once. Now you can say in 
general that this resistance arises from the repugnance which 
two bodies have to occupy the same phice, which may l)e 
called impenetrability. Thus when one body makes an effort 
to enter, it at the same time forces the other to attempt to 
leave or to prevent its entrance. But tliat kind of incompati- 
bility which makes one or the other, or both together, yield, 
being once assumed, there are several reasons besides the one 
named which make one body resist another which endeavors 
to compel its departure. They are either in it or in the neigh- 
boring bodies. There are two which are in itself ; one is pas- 
sive and constant, the other active and variable. The first is 
what I call inertia,^ after Kepler^ and Descartes, which impels 
matter to resist motion, and which it is necessary to destroy 
by force in order to move a body, suf)posing that there were 
neither gravity nor adhesion. Thus a body which undertakes 
to drive forward another, experiences for that reason this re- 
sistance. The other cause, which is active and variable, con- 
sists in the impetuosity of the body itself, which does not 
yield without resistance at the moment its own impetuosity 
carries it into a place. The same reasons reappear in the 
neighboring bodies when the body which resists is unable to 
yield without causing the others to yield also. But then a 
new consideration comes in — viz.: compactness (fermete) or 
the adhesion of one body to another. This adhesion^ makes 
it impossible to move one body without at the same time mov- 
ing the other to which it adheres, and this causes a kind of 
traction in reference to this other. This adhesion so acts that, 
even should we put aside inertia and manifest impetuosity, 
there would be resistance ; for if space is conceived as filled 
with matter perfectly fluid, and if a single hard body were 
placed within it, this hard body (supposing there were in the 
fluid neither inertia nor impetuosity) will be moved therein 
without finding any resistance; but if space were full of little 

1 Gerhardt reads " incertie " ; evideiitly au error. — Tr. 

2 John Kepler, loTl-KI.SO, one of the creators of modern astronomy. His 
complete works were edited hy Dr. Cii. Friscli, Joannis Kepleri opera omnia, 
8 vols., Franldort: 1858-1871. -Tr. 

8 Erdmann and Jacques add " souvent," often. — Tr. 



1_.| LKIBM'PZ'S CKITIQUE OF LOCKE [ijk. ii 



cubos, the resistance vvliicli the hard body would find, should 
it be moved among the cubes, would come from the fact that 
the little hard cubes, on account of their hardness or because 
of the adhesion of their parts one to another, would with diffi- 
culty be separated as much as would be necessary to make a 
circle of movement, and to fill up the place of the body moved 
at the moment it departs. But if two bodies should enter at 
the same time by the two ends into a tube open on both sides, 
and should fill it to its capacity, the matter in this tube, how- 
ever fluid it be, would resist by its impenetrability alone. 
Thus, in the resistance of which we are here treating, we have 
to consider the impenetrability of bodies, inertia, impetuosity, 
and adhesion. It is true that, in my opinion, this adhesion of 
bodies arises from a more subtile motion of one body toward 
another; but, as this is a point which may be disputed, it must 
not be assumed at first. And for the same reason we must 
only assume at first an original, essential solidity, which makes 
the place always equal to the body, that is to say that the iu- 
coiupatibility, or, to speak more accurately, the non-consistence ^ 
of bodies in the same place is a perfect impenetrability which 
receives neither more nor less, since many maintain that sensi- 
ble solidity can arise from a repugnance on the part of bodies 
to be found in the same place, but which will not prove to be 
an invincible repugnance. For all the ordinary Peripatetics 
and many others believe that the same matter can fill more or 
less space, which phenomenon they call rarefaction or conden- 
sation, not in appearance only (as when water is squeezed from 
a sponge), but rigorously, like the scholastic conception of the 
air. I am not of this opinion ; but I do not think that I ought 
at first to assume the opposite opinion, the senses, apart from 
the reasoning faculty, not sufficing to establish this perfect im- 
penetrability, which I hold to be true in the order of nature, 
but which is not learned by sensation alone. And some one 
may claim that the resistance of bodies to compression arises 
from an effort of the parts to spread themselves when they 
have not their entire liberty. For the rest the eyes aid 
greatly in proving these qualities, coming to the assistance of 

1 Leibnitz's word is " rinconsistence," and, as it is apparently technieal, I 
have decided to transfer it, merely changing the form of the negative in- to 
non- to avoid ambiguity. — Tr. 



cii. IV] ON HUMAN UNDERSTANDING 125 

touch. And at bottom solidity, so long as it presents a dis- 
tinct idea, is conceived by pure reason, although the senses 
furnish the reasoning faculty with the proof that it is in 
nature. 

§ 4. Ph. We are at least agreed that the solidity of a body 
carries with it the filling of the space it occupies in such a 
way as absolutely to exclude every other body [if a space can 
be found in which there was none before], while hardness [or 
the consistence rather which some call compactness (fer- 
mefe)^, is a strong union of certain parts of matter, which 
make up masses of a sensible size, so that the whole mass does 
not easily change its form. 

Th. [This consistence, as I have already remarked, is pre- 
cisely what makes it diificult to move one part of a body with- 
out the other, so that when one part is pushed, the other, 
which is not pushed, and which does not fall within the line 
of tendency, is nevertheless induced to go from that side by a 
kind of traction; and, further, if this last part finds any obsta- 
cle which holds or pushes it back, it draws it along, or holds 
back, also, the first part ; and this action is always reciprocal. 
The same thing sometimes happens in the case of two bodies 
which do not touch and which do not form a continuous body 
whose parts are contiguous ; and yet, the one pushed compels 
the other to go without pushing it, so far as the senses can 
give us knowledge. Of this the animant,^ electrical attraction, 

1 See Krauth-Fleming, Vocab. Philos. Sciences, pp. 28, 29, aud 571, edition 
of 1877, New York: Sheldon & Co., 1883. The animant is that which pos- 
sesses and imparts life. Together with its cognates aniniallty, animalish, 
anlmulht, used frequently by Cudworth. See Intell. Syst., 514, " Ut sit 
Animans, that it be Animant, or endued with Life, Sense, and Understand- 
ing." Ibid., 198. "But no Atheist ever acknowledged conscious imimality 
to be a first principle in the universe ; nor that the whole was governed by 
any animalist, sentient, and understanding nature, presiding over it as the 
head of it." The term being technical, and, with its cognates, more or less 
current in the seventeenth century, it seemed best to retain it, defining and 
illustrating as above. Its meaning is, I think, sufficiently evident. It is to 
be noticed, however, that Erdmann, in his Errores Tirpofjntphici, prefixed 
to his edition, reads aimcmt instead of animant. Jacques's text also has 
aimctnt. Tlie translation would then he: The loadstone or marinet ; aud 
Schaarschmidt, following this reading, renders it " der Magnet," in his German 
translation of the iVoureaux Essais, in J. H. v. Kirchmann's Philos. Bibliothek, 
Berlin, 1873. As I translate on the basis of Gerhardt's text I retain his read- 
ing and its translation, with the note explaining tlie term, although at the 
present writing the reading of Erdmann and Jacques seems more congruous 
with the context, and so more likely to be the true one. — Tb. 



120 LKIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



and that which was formerly ascribed to the fear of a vacuum, 
furnish examples.] 

Ph. It seems that, in general, hard and soft are names which 
we give to things solely as related to the particular constitu- 
tion of our bodies. 

Th. [But then many philosophers would not ascribe hard- 
ness to their atoms. The notion of hardness does not depend 
upon the senses, and its possibility can be conceived by the 
reason, although we are further convinced by the senses that 
it is actually found in nature. I Should, however, prefer the 
word compactness — fermete (if I were allowed to use the word 
in this sense) — to that of hardness, for there is some compact- 
ness even in soft bodies. I seek even a more suitable and 
general term, like consistence or cohesion. Thus I would 
oppose hard to soft, solid to fluid, for wax is soft, but, unless 
melted by heat, it is not fluid and preserves its bounds ; and 
in fluids even there is ordinarily cohesion, as is shown in drops 
of water and of mercury. I am also of opinion that all bodies 
have some degree of cohesion, as I also believe that there are 
none which do not have some fluidity, and whose cohesion is 
not capable of being overcome ; so that, in my opinion, the 
atoms of Epicurus,-^ whose hardness is supposed to be invinci- 
ble, cannot occur any more than the subtile, perfectly fluid 
matter of the Cartesians. But this is not the place to justify 
this opinion or to explain the rationale of cohesion. 

Ph. The perfect solidity of bodies seems to be justified by 
experiment. For example, water incapable of yielding, passed 
through the pores of a hollow globe of gold, in which it was 
confined, when this globe was put under pressure in Florence. 

Til. [There is something to be said as to the inference which 
you draw from this experiment, and from what happened in 
the case of the water. The air as well as the water is a body, 
which is compressible at least ad sensiun. and those who would 
maintain a complete rarefaction and condensation will say that 
water is already too compressed to yield to our machines, as 
air very much compressed would resist also a further compres- 
sion. I admit, however, on the other hand, that if any slight 
change should be noticed in the volume of the water, it might 
be ascribed to the air which is enclosed in it. Without enter- 
1 Epicurus, December, 3i2, or January, 341-270 b.c. — Tr. 



CH. IV] ON HUMAN UNDERSTANDING 127 

iug now into the discussion whether pure water is not itself 
compressible, as it is found that it is dilatable when it evapo- 
rates, I am, nevertheless, decidedly of the opinion of those who 
believe that bodies are perfectly impenetrable, and that there 
is, save in appearance, neither condensation nor rarefaction. 
But this kind of experiment is as little capable of proving this 
as the tube of Torricelli ^ or the machine of Guerike ^ are suffi- 
cient to prove a perfect vacuum. '^ 

§ 5. Ph. If the body were strictly capable of rarefaction 
and compression, it might change in volume or extension, but 
that not being so, it will be always equal to the same space ; 
and, moreover, its extension will be always distinct from that 
of space. 

Th. [The body might have its own extension, but it does not 
thereby follow that it would be always determinate or equal 
to the same space. Nevertheless, although it may be true that 
in the conception of body something besides space is conceived 
of, it does not thereby follow that there are two extensions — 
that of space and that of body ; for it is as when in conceiving 
several things at once, one conceives something besides the 
number, viz. : res numeratce ; and, moreover, there are not two 
multitudes, the one abstract — i.e., that of number; the other 
concrete — i.e., that of the things enumerated. Likewise one 
can say that it is not necessary to think of two extensions — 
the one abstract, of space, the other concrete, of body, the con- 

1 Evangelista Ton-icelli, 1608-164:7, a celebrated Italian physicist and mathe- 
matician, the inventor of the mercurial barometer, long called the " Torricel- 
lian tube." He had a controversy with Roberval (vid. ante, p. 107 and note) as 
to the discovery of the quadrature of the cycloid. Torricelli found the area of 
tlie curve, and furnished the demonstration of it, which he published in a tract, 
l)e motu gravium naturaliter accelerato in his Opera geometrica, Florence, 
1644. — Tr. 

2 Otto von Guerike, 1602-1686, a German physicist, who devoted himself 
especially to experimenting upon the vacuum, and who, after many attempts, 
finally, in 1654, hit upon an air machine, which enabled him to undertake 
a series of experiments upon the different effects of vacuum. His labors and 
principal observations have been published under the title, Eyperimenta nova, 
ut vocant, Magdeburgica, de vacuo spatio, etc., Amsterdam, 1672. — Tr. 

3 Descartes maintained the impossibility of a vacuum. Cf. Prin. Philos., XL, 
§ 16; English translation by John Veitch, LL.D., The Method, Mcdildtioiia, 
and Selections from the Principle.'^ of Descartes, etc., 8th ed., p. 211, Kdin- 
bnrgh: William Blackwood & Sons, 1881; also vid. ante, p. 16, and tli(i fifth 
letter to Samuel Clarke, § :54, Gerhardt, Vol. 7, p. ;«I6; Erdmann, p. 766, b; 
translation, Duncan, Philos. Works of Leibnitz, j). 262. — Tk. 



128 LEIBNITZ'S CRITIQUE OF LOCKE [bk. n 

Crete existing as such only through the abstract. And as 
bodies pass from one part of space to another — i.e., change 
order aniong themselves — things also pass from one part of 
the order or of a number to the other, when, for example, the 
first becomes the second and the second the third, etc. In 
fact, time and space are only kinds of order,^ and in these 
orders the vacant place (which in relation to space is called 
vacuum), if there were any, would show the possibility only of 
that which is lacking together with its relation to the actual. 

Ph. I am nevertheless very glad that you agree with me 
that matter does not change in volume. But you seem to go 
too fai", sir, in not recognizing two extensions, and you re- 
semble the Cartesians, who do not distinguish space from mat- 
ter.- Now it seems to me that if a class is found who, not 
having these distinct ideas (of space and of solidity which fills 
it), blends them and makes of the two one only, we cannot see 
how these persons can converse with others. They are like a 
blind man who, when another man speaks to him of scarlet, 
thinks it resembles the sound of a trumpet. 

Th. [But I hold at the same time that the ideas of exten- 
sion and solidity, like that of scarlet-color, do not consist in an 
/ knoio not ivhat.^ I distinguish extension and matter, contrary 

1 Cf. Letter to Des Bosses, June 16, 1712, Gerhardt, Vol. 2, p. 450 ; Erdmann, 
p. 682, b: " Spatiura fit ordo coexistentium phfeuomenorum, iit tempiis succes- 
sivorum," i.e. " Space is tlie order of co-existing, as time of successive plie- 
nomena"; also the letters to Clarke, Gerhardt, Vol. 7, pp. 345 sq.; Erdmaun, 
pp. 746 .s^., translation, Duncan, Philos. Works of Leibnitz, pp. 238 .s^. ,• Kant, 
Kritik d. r. Vernunft, Erst. Th., Abscb. 1 und 2, §§ 2-7, and translations of 
Max Miiller, and Watson in The Fhilosophy of Kant, as contained in extracts 
from his own icritinr/s. New York: Macmillan & Co., 1888. — Tr. 

2 Cf. Descartes, Prin. Fhilos. II., §§ 8-15; Veitch's translation, pp. 236-240. 
— Tr. 

3 Leibnitz's expression is "nnje ne say qiioi." Schaarschmidt trans- 
lates it"ein undenkbares Etwas." It seems to be equivalent to an indef- 
inite somewhat which is the ultimate essence of thinos, and which is the 
cause of, and by differentiation becomes, the particular. Leibnitz, then, 
means to say that the ideas of extension and solidity are distinct. Cf. John 
Dewey, Ph.D., Leibniz's Neio Essays concerninr/ the Human Understand inrj, 
a Critical Exposition, p. 1.34. As applied to personal beings, it seems to he 
equivalent to the "unconscious presentations" — i.e. "the dark side of the 
soul-life," " the proper basis of Individuality." " Genius, disposition, feeling, 
are the tenns by which a later time has designated what Leibnitz calls the 
je ne sais quoi, whereby eveiy one is preformed by natui-e to something par- 
ticular" ("Ganz wie bei dem blossen Monaden ihre iiidividuelle Beschaffen- 
heit in dem jNIomente der Schranke, der materia prima, lag, ganz so werden 



cii. v] ON HUMAN UNDEKSTANDING 129 

to the view of the Cartesians. Still I do not believe that there 
are two extensions ; and since those who dispute over the dif- 
ference between extension and solidity are agreed on several 
truths upon this subject and have some distinct notions, they 
can find therein the means of extricating themselves from their 
disagreement; thus the assumed difference upon ideas ought 
not to serve as a pretext for eternal disputes, although I know 
that certain Cartesians, otherwise very able, are accustomed 
to intrench themselves in the ideas which they pretend to 
have. But if they would avail themselves of the means which 
I have before given for recognizing ideas true and false, and 
of which we shall speak also in the sequel, they would retire 
from a position which is not tenable. 



CHAPTER V 

OF SIMPLE IDEAS WHICH COME BY DIFFERENT SENSES 

Ph. The ideas, the perception of which comes to us from 
more than one sense, are those of space, or extension, or fig- 
ure, of motion and rest. 

Th. [The ideas which are said to come from more than one 
sense, like those of space, figure, motion, rest, are rather from 
common-sense, that is to say, from the mind itself, for they 
are ideas of the pure understanding, but related to externality, 
and which the senses make us perceive ; they are also capable 
of definition and demonstration.] 

hler diese unbewussteu Vorstellungen, d. h. wird die dunkle Seite des Seelen- 
lebeiis, als der eigeutliclie Gruiid der Individualitiit bestimmt. Geuius, 
Gemiitli, Gefiilil sind die Worte, mit denen eine spiltere Zeit das bezeicbiiet 
hat, was Leibnitz das je ne sais qiioi neiint, wodureh Jeder von Natur zu 
etwas Besouderein priiformirt ist." Erdmann, Grimdriss d. Gesch. d. Philos., 
3te Aullage 2te Bd. § 288, 5, s. IGl. Berlin, 1878; English translation, Vol. 2, 
p. 191, London: Swan Sonnenschein & Co., 1889). Cf. also Leibnitz, Neio 
Essays, Preface, vid. ante, pp. 47 sq.. Book II., chap. 1, § 15, Th., sq., and 
Erdmann's exposition of the same, op. cit., s. 160, 161. Also Professor Dewey's 
most excellent work cited above. — Tr. 

K 



180 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



CHAPTER VI 

OF SIMPLE IDEAS AVHICH COME BY REFLECTION 

Ph. The simple ideas which come by reflection are the ideas 
of the understanding and of the will [for we ourselves per- 
ceive them in reflecting upon ourselves.] 

Th. [It is doubtful if all these ideas are simple, for it is 
clear, for example, that the idea of the will includes that of 
the understanding, and that the idea of motion contains that 
of figure. 

CHAPTER VII 

OF IDEAS WHICH COME BY SENSATION AND REFLECTION 

§ 1. Ph. There are some simple ideas which make themselves 
perceived in the mind by all the avenues of sensation and by 
reflection also — viz.: pleasure, pain, power, existence, unity. 

Th. [It seems that the senses cannot convince us of the exist- 
ence of sensible things without the aid of the reason. Thus I 
should think that the idea^ of existence comes from reflection. 
That of power also and of unity come from the same source, 
and are of a wholly different nature from the perceptions of 
pleasure and pain.] 

CHAPTER VIII 

OTHER CONSIDERATIONS UPON SIMPLE IDEAS 

§ 2. Ph. What shall we say of ideas of privative qualities? 
It seems to me that the ideas of rest, darkness, and cold are as 
positive as those of motion, light, and heat. jSTevertheless, in 
proposing these privations as the causes of privative ideas I 
follow the common view ; but in the main it will be difiicult 
1 The French is " la consideration de I'existence." — Tr. 



CH. VIII] ON HUMAN UNDERSTANDING 131 

to determiue whether there is really any idea which arises 
from a privative cause until it has been determined whether 
rest any more than motion is a privation. 

Th. [I had not believed that we could have reason to doubt 
the privative nature of rest. It suffices it that motion in the 
body be denied, but it does not suffice for motion to deny rest, 
and it is necessary to add something more to determine the de- 
gree of motion, since it receives materially more or less, while 
all rest is equal. It is another thing when we speak of the 
cause of rest, which must be positive in the secondary ' matter 
or mass. I should furthermore regard the very idea of rest as 
privative — i.e., that it consists only in negation. It is true 
that the act of denial is positive.] 

§ 9. Ph. The qualities of things being the faculties they have 
of producing in us perception of ideas, it is well to distinguish 
these qualities. They are primary and secondary. Extension, 
solidity, figure, number, mobility are the original qualities 
inseparable from body which I call primary. § 10. But I call 

1 Leibnitz constantly distinguislies between primary and secondary matter. 
Primary matter is the primitive passive power belonging to eacli separate 
being as such, by wliieli it is distinguished from God and in which is grounded 
the possibility of representing itself as different. It is essential to and insepa- 
rable from the entelechy, or principle of activity, which it completes, the two 
united jn'oducing the perfect substance or monad. By itself it is a pure 
abstraction or potentiality, and not a substance. It is equivalent to confused 
ideas, thus to an imperfect manifestation or phenomenon of spirit — since all 
matter is ultimately spirit or has its final reason or source in spirit — but a 
potentiality of spirit capable sometime of realizing perfectly all its intrinsic, 
but now latent, activity. Secondary matter is a mass resulting from the union, 
of many monads or complete substances, each having its own jirimary matter 
and its own entelechy, with their derived forces, activities, receptivities. It 
is not, however, a substance ; and its extension resulting from the union of 
non-extended simple substances is only phenomenal, though not on that 
account unreal, being due to our confused perception, and consisting in the 
impenetrability, resistance, or inertia of the monad on its passive side ; an 
extension which will disappear when the activity of the monad becomes pure 
and perfect. Cf. Letters to Tolomei, Dec. 17, 1705, Gerhardt, Vol. 7, pp. 407- 
468; Des Bosses, March 11, Oct. 16, 1706, March 16, 1709, Gerhardt, Vol. 2, 
pp. 304, 324, 368 ; Erdmann, pp. 435, 440, 456; De anima hrutorvm, 1710, G. 7, 
328; E. 463; Letters to Rud. Christ. Wagner, June 4, 1710, G. 7, 528, E. 405; 
translation, Duncan, Phi.los. Work.'i of Leibnitz, p. 190 sq.; Bierling, Aug. 12, 
1711, G. 7, .500-.502, E. 077-678 ; Reraond, Nov. 4, 1715, G. 3, 656-(i(!0 ; E. 735- 
737 ; Feb. 11, 1715, § 4 (reply to Remond's fourth difficulty stated in his letter to 
Leibnitz, Jan. 9, 1715), G. 3, 636, E. 725 ; also the writing dated July, 1714, and 
first published by Gerhardt, 3, 622-(i24. Cf. also Erdmann, Gnind. d. Ge.srh 
Philos., 3d ed., § 288, 2, 3 ; Dewey, Leibnitz, New Essays, chaps. 7 and 8. — Tr. 



132 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



secondary (]ualities the faculties or powers of bodies to produce 
certain sensations in us, or certain effects in other bodies, as 
the tire, for example, produces a certain effect in the wax when 
melting it. 

Th. [I think Ave can say that when the power is intelligible, 
and can be distinctly exj^lained, it should be reckoned among 
the 2>rimari/ qualities; but when it is only sensible and gives 
only a confused idea, it should be put among the secondary qual- 
ities.^ 

§ 11. Ph. These primary qualities show how bodies act upon 
one another. Now, bodies act only by impulse, at least so far 
as we can conceive the process, for it is impossible to under- 
stand how bodies can act upon what they do not touch, which 
is equivalent to imagining that they can act where they are 
not. 

Th. [I am also of the opinion that bodies act only by impulse. 
Yet, there is some difficulty in the proof of what I have just 
heard ; for attraction sometimes occurs without contact, and we 
can touch and draw without any visible impulse, as I have 
shown above ^ in speaking of hardness. In the case of the atoms 
of Epicurus, the one part pushed would draw the other with 
it, and would touch it in putting it in motion without impulse. 
And in the case of attraction between contiguous things we 
cannot say that the one which draws with itself acts where it 
is not. This reason would militate only against attractions 
from a distance, as would be the case in reference to what are 
called vires centrij^etce advanced by some scholars.] 

§ 13. Ph. Now, certain particles, striking our organs in a cer- 
tain way, cause in us certain sensations of colors or tastes or 
other secondary qualities which have the power of producing 
these sensations. And it is no more difficult to conceive that 
God can attach such ideas (as that of heat) to motions, with 
which they have no resemblance, than it is difficult to conceive 
that he has attached the idea of pain to the motion of a piece 
of iron which divides our flesh ; Avhich motion the pain in no 
manner resembles. 

Th. [It is not necessary to suppose that ideas like those of 
color or of pain are arbitrary and without relation or natural 
connection with their causes ; it is not the custom of God to 

1 Cf. Bk. n., Chap. 4, § 4, Th., ante, p. 125, sq. —Tr. 



CH. viii] ON HUMAN UNDERSTANDING 133 

act with so little oixler and reason. I should rather say that 
there is a kind of resemblance, not complete and, so to speak, 
m terminis, but expressive, or a kind of orderly relation, as an 
ellipse, and even a parabola or hyperbola resemble in some 
sense the circle of which they are a projection upon a plane, 
since there is a certain exact and natural relation between 
what is projected and the projection which is made, each point 
of the one corresponding by a certain relation to each point of 
the other. This the Cartesians do not sufficiently consider, 
and for once you have deferred to them more than has been 
customary with you, and without reason for so doing.] 

§ 15. Ph. I tell you what appears to me, and the appear- 
ances are that the ideas of the primary qualities of bodies 
resemble these qualities, but the ideas produced in us by the 
secondary qualities resemble them in no way. 

Th. [I have just shown how there is resemblance or exact 
relation in respect to the secondary as well as the primary 
qualities. It is certainly reasonable that the effect correspond 
to its cause ; and how assert the contrary, since you know dis- )c' 
tinctly neither the sensation of blue (for example) nor the 
motions which produce it ? It is true that pain does not. . 
resemble the motion of a pin, but it may very well resemble 
the motions which this pin causes in our body, and represent 
these motions in the soul, as I have no doubt it does. It is 
also for this reason that we say that the pain is in our body 
and not that it is in the pin ; but we say that the light is in the 
fire, because there are in the fire motions which are not dis- 
tinctly sensible apart from it, but whose confusion or con- 
junction becomes sensible, aiid is represented to us by the idea 
of light. 

§ 21. Ph. But if the relation between the object and the 
sensation be natural, how can it be, as we notice in fact, that 
the same water may appear warm to one hand and cold to the 
other ? which shows that the heat is no more in the water 
than the pain is in the pin. 

Th. [This proves all the more that heat is not a sensible 
quality or power of making itself felt absolutely all at once, 
but that it is relative to the suitable organs ; for a particular 
motion in the hand may be mixed with it and change its appear- 
ance. Light, furthermore, does not make itself evident to 



134 LEIBNITZ'S CUITIQUE OF LOCKE [bk. ii 

l»;i(lly constituted eyes, and wlien they are themselves filled 
with a groat light, they are insensible to a less. Even the 
primary qualities (according to our classification) — for ex- 
ample, unity and number — may not appear as they should; 
for, as Descartes has already stated, a globe touched by the 
fingers in a certain way appears double, and mirrors or glasses 
! cut in facets multiply the object. It does not then follow that 
what does not always appear the same is not a quality of the 
object, and that its image does not resemble it. And as for 
the heat, when our hand is very warm, the medium heat of the 
water does not make itself felt, and modifies rather that of 
the hand, and consequently the water appears to us cold ; as 
the salt water of the Baltic Sea mixed with the water of the 
Sea of Portugal^ would lessen its specific saline quality, 
although the former be itself salt. Thus, in any case, we can 
say that the heat belongs to the water of a bath, although it 
may appear cold to any one, as honey is called absolutely 
sweet, and silver white, although the one appears bitter, the 
other yellow to some diseased persons, for the classification is 
made upon the basis of the most common (conditions) ; and 
yet it remains true that, when the organ and the medium are 
constituted as they should be, the internal motions and the 
ideas which represent them to the soul resemble the motions 
of the object which cause color, heat, pain, etc., or, what is 
here the same thing, express it by means of a relation suffi- 
ciently exact, although this relation does not distinctly appear 
to us, because we cannot disentangle this multitude of small 
impressions either in our soul or our body or in what is with- 
out. 

§ 24. Ph. We consider the qualities which the sun has of 
blanching or melting wax or hardening mud only as simple 
powers, without thinking of anything in the sun correspond- 
ing to this blanching, softness, or hardness ; but heat and light 
are commonly regarded as real qualities of the sun. Properly 
considered, however, these qualities of light and heat which in 
me are perceptions are not in the sun in any other manner 
than the changes produced in the wax when it is blanched or 
melted. 

1 Obsolete name for that part of the Atlantic which washes the coast of 
Portuc'al. — Tr. 



cii. IX] ON HUMAN UNDERSTANDING 135 

Th. [Some have pushed this doctrine so far that they have 
desired to persuade us that if any one could tovich the sun he 
would find there no heat. The counterfeit sun which makes 
itself felt in the focus of a mirror or a burning-glass may disa- 
buse people of this notion. But as to the comparison between 
the power of heating and that of melting, I dare affirm that if 
the melted or blanched wax had feeling, it would feel some- 
thing similar t6 what we feel when the sun warms us, and 
would say, if it could, that the sun is warm, not because its 
whiteness resembles the sun — for when faces are tanned in 
the sun their brown color should likewise resemble it — but 
because there are in the wax motions which are related to 
those in the sun which cause them ; its whiteness may come 
from another cause, but not the motions which it has had in 
receiving it (whiteness) from the sun.] 



CHAPTER IX 

OF PERCEPTION 

§ 1. Ph. Come we now to the ideas of reflection in particu- 
lar. Perception is the first faculty of the soul which is occu- 
pied with our ideas. It is also the first and simplest idea 
which we receive by reflection. Thought signifies often the 
mind's working upon its own ideas, when it acts and considers 
a thing with a certain degree of voluntary attention : but in 
what we call perception the mind is ordinarily purely passive, 
not being able to avoid perceiving what it actually perceives. 

Th. [We might perhaps add that the animals have percep- 
tion, and that it is not necessary that they have thought, that 
is to say, that they have reflection or what may be its object. 
We ourselves also have minute pt^^'f^^ptions of which we are not 
conscious in our present state. It is true that we might very 
well perceive them ourselves, and reflect upon them, if we 
were not turned aside by their multitude, which distracts our 
mind, or if they were not effaced, or rather obscured, by 
greater ones. 

§ 4. Ph. I admit that when the mind is strongly occupied 



130 LEIBNITZ'S CUITIQUE OF LOCKE [bk. 



in contemplating certain objects it does not perceive in any 
way the imi>ression whieli certain bodies make upon the organ 
of iiearing, although the impression may be quite strong ; but 
no perception arises therefrom if the soul takes no cognizance 
thereof. 

Th. [I should prefer to distinguish between perception and 
consciousness {s'appercevoir)} The perception of light and 
color, for example, of which we are conscious, is composed of 
many minute perceptions, of which we are not conscious ; and 
a uoise which we perceive, but of which we take no notice, 
becomes apperceptihle by a little addition or increase; for if 
what precedes make no impression upon the soul, this little 
addition would also make none, and the whole would make 
no more. I have already touched upon this point (Ch. II,- of 
this book, §§ 11, 12, 15, etc.)]. 

§ 8. Ph. It is proper to remark here that the ideas which 
arise from sensation are often altered by the mental judgment 
of grown persons without their perceiving the fact. A flat 
circle with various light and shade represents the idea of a 
globe of uniform color. But, as we are accustomed to distin- 
guish the images of bodies and the changes of the reflections 
of light according to the figures of their surfaces, we put in the 
place of what appears to us the cause the image itself, and 
confuse the judgment with the appearance. 

Til. Nothing is truer, and this it is which gives to painting 
the means of deceiving us by the artifice of a very extended 
perspective. When bodies have flat surfaces, they can be rep- 
resented without employing shadows by giving only their con- 
tours and by simply making pictures after the fashion of the 
Chinese, but better proportioned than theirs. The same 

^ Cf. Leibnitz, Principes. de la nature et de la grace fonde's en raison, § 4. 
" It is well to make a distinction between the perception, which is the internal 
condition of the monad representing external things, and apperception, which 
is consciousness or the reflective knowledge of this internal state: the latter 
not being given to all sonls, nor at all times to the same soul." For the 
entire piece, which is a brief statement of his philosophical system prepared 
by Leibnitz himself, with the greatest care, about 1714. rf. Gerhardt, Vol. fi, 
pp. 598-(i06; Erdmann, pp. 714-718; translation, Duncan. PhiJos. Works of 
Leibnitz, pp. 20t>-217, and note r,fi, p. .387 op. cit. Also Hamilton's Reid, 8th 
ed., Vol. 2, p. 877, note, and Kranth-Fleming, Vocah. Philos., ed. of 1877, 
articles "Apperception," p. .^S, "Consciousness," pp. 1(B-11.3, 613, "Percep- 
tion," pp. .37.3-374, 807-809, "Perceptions (Obscure)," pp. 374-376.— Tr. 

2 This should be chap. 1, I think.— Tr. 



cii. IX] ON HUMAN UNDERSTANDING 137 

custom is observed in designing medals, in order that the 
draughtsman may be less likely to depart from the precise 
form of the antique. But we cannot distinguish exactly by 
means of the design the interior of a circle from the interior of 
a spherical surface bounded by this circle without the aid of 
shadows, the interior of each having neither points distin- 
guished nor distinguishing features, although there is, however, 
a great difference which ought to be indicated. Desargues ^ 
has accordingly given precepts upon the force of tints and 
shades. When, then, a painting deceives us there is a double 
error in our judgments ; for first we put the cause for the effect, 
and think we see immediately the cause of the image, in which 
we resemble a little a dog who barks at a mirror ; for, properly 
speaking, we see only the image, and we are affected only by- 
the rays of light. And since the rays of light require time (how- 
ever little it be), it is possible for the object to be destroyed in 
this interval, and for it no longer to exist when the ray reaches 
the eye, and that which no longer exists cannot be the object 
present to the sight. In the second place, we further deceive 
ourselves when we put one cause for another, and think that 
what comes only from a flat picture is derived from a body, so 
that in this case there is in our judgments all at once a me- 
toni/mj/ and a metaphor ; for even the figures of rhetoric pass 
into sophisms when they impose on us. This confusion of the 
effect with the cause, whether true or false, often enters into 
our judgments, moreover, upon other things. Thus we feel 
our bodies7 oF "what touches them, and we move our arms by 
means of an immediate physical influence, which we think 

1 Gaspare! Desarsjnes, 1593-16n2, a French geometer and engineer, a friend 
of Descartes, Gassendi, Pascal, and Roberval, who wrote on the application of 
geometry to the arts as well as on geometry itself. These writings have been 
lost and their titles are known only through the engraver Bosse. Of his 
Methode univer.ielle de mettre en perspective des objects donnes riellement, 
oil en derns, avec leurs proportions, mesxires, eloignments, sans employer 
aucun point qui soit hors du champ de I'ouvraf/e, 1630 or 1636, Descartes thus 
speaks in a letter to Mersenne ("written toward the end of April, 1637," 
according to Cousin, CEuvres de Descartes, Vol. 6, pp. 250-250, Paris: 1824- 
1S26), " Je n'ai reiju que depuis pen de jours le petit livre in folio, qui traite 
de la perspective: il n'est pas a dcsapprouver, outre que la curiosite et la 
nettete du langage de son anteur sont a estimer," I received only a few 
days ago the little hook in folio treating of perspective: it is not to be con- 
demned : further the exactness and perspicuity of the author's language are to 
1)0 admired. — Tr. 



i;j8 LEIBNITZ'S CRITIQUE OF LOCKE [inc. ii 

constitutes the connection of the soul with the body, while in 
truth we feel and change in that way only what is in us. 

Fh. I will at this time propose to you a problem which the 
h-'arnod a\Ir. j\Iolyneux/ who employs so profitably his excel- 
k>nt genius in the promotion of the sciences, communicated to 
the illustrious Mr. Locke. Here it is nearly in his own 
terms : Suppose a man blind from birth, now grown up, who 
has learned to distinguish by touch a cube from a globe of the 
same metal, and almost of the same size, so that when he 
touches the one or the other he can tell which is the cube and 
which the globe. Suppose that the cube and the globe being 
placed upon the table, this blind man comes to enjoy his sight. 
The question is, if in seeing them without touching them he 
could distinguish them, and tell which is the cube and which 
the globe. I pray you, sir, tell me what is your opinion upon 
the matter. 

Th. I ought to give some time to thought upon this ques- 
tion, which appears to me quite curious : but since you press 
me for an immediate reply, I would venture to say between 
ourselves that I think that supposing the blind man knows 
that these two figures which he sees are those of the cube and 
the globe, he could distinguish them and say, without touch- 
ing, This is the globe, this the cube. 

Ph. I fear lest it may be necessary to put you in the crowd 
of those who have failed to answer Mr. Molyneux ; for he sent 
word in the letter which contained this question, that, having 
proposed it upon the occasion of Mr. Locke's Essay on Under- 
standing to different persons of very penetrating minds, he 
had found scarcely one among them who at once gave such a 
reply upon that point as he thinks should be made, although 
they were convinced of their error after having heard his 
reasons. The reply of this penetrating and judicious author 
is negative ; for (he adds) while this blind man has learned 
by experience of some kind the globe and the cube as they 
affect his touch, he does not, however, yet know that what 
affects the touch in such or such manner must strike the eyes 

1 William Molyneux, 1656-1698, an eminent mathematician. He founded in 
Dublin, in January, 1()84, a Pliilosopliical Society on the model of the Royal 
Society at London. His principal work, Bioptrica N'ova, in two parts, was 
published at London in 1G92-1709, in 4to. — Xb. 



cii. IX] ON HUMAN UNDERSTANDING . 130 

in sucli or such manner, nor that the projecting angle of the 
cube, which presses his hand in an unequal manner, must 
appear to his eyes as it appears in the cube. The author of 
the Essay declares himself at once of the same opinion. 

Th. Perhaps Mr. Molyneux and the author of the Essay are 
not so far from my opinion as at first appears, and the reasons 
for their view, contained apparently in the letter of the for- 
mer, who has employed them with success in order to convince 
men of their error, have been purposely suppressed by the 
latter in order to give more exercise to the minds of his 
readers. If you will weigh my reply, you will find, sir, that 
I have placed therein a condition which can be considered as 
comprised in the question — viz. : that the question is that of 
distinguishing alone, and that the blind man knows that the 
two figured bodies, which he should distinguish, are there, and 
that thus each of the appearances which he sees is that of the 
cube or that of the globe. In this case it appears to me 
beyond doubt that the blind man who ceases to be such can 
distinguish them by the principles of reason, united with that 
sense-knowledge with which touch has before furnished him. 
For I do not speak of that which he will do perhaps in fact 
and immediately, dazzled and confused by the novelty, or from 
some other cause little accustomed to draw inferences. The 
basis of my view is that in the globe there are no points dis- 
tinguished by the side of the globe itself, all there being level 
and without angles, while in the cube there are eight points 
distinguished from all the others. If there were not this ^ 
means of discerning the figures, a blind man could not learn * 
the rudiments of geometry by touch. But we see that those 
born blind are capable of learning geometry, and have indeed 
always certain rudiments of a natural geometry, and that 
most often geometry is learned by sight alone, without the 
use of touch, as indeed a paralytic or other person to whom 
touch has been almost denied might and even must do. 
And these two geometi'ies — that of the blind man and that of 
the paralytic — must meet and agree, and indeed return to the 
same ideas, although there are no common images. This again _ 
shows how necessary it is to distinguish images from exacts* 
ideas, which consist in definitions. It would really be very • 
interesting and instructive to make a complete examination of 



140 



LKlHNirZ'S CRITIQUE OF LOCKE [isk. ii 

the ideas of a man born blind, to understand the descriptions 
ho makes of figures. For he may come to this, and he may 
■ even understand tlie doctrine of optics, so far as it is depeud- 
' ent ujion distinct and mathematical ideas, although he could 
not attain to a conception of dair-confus, that is to say, the 
image of light and of colors. This is why a certain one born 
blind, after having attended lessons in optics, which he 
ajtpeared fully to understand, replied to some one who asked 
him what he thought light was, that he thought it must be 
something pleasant like sugar. It would likewise be very 
im])ortant to examine the ideas which a man born deaf and 
dumb may have of things not figured, whose description we 
usually have in words, and which he must have in a manner 
wholly different from, though it may be equivalent to ours, as 
Chinese writing is in fact equivalent to our alphabet, although 
it is infinitely different, and might appear to have been in- 
vented by a deaf man. I learn, through the favor of a great 
prince, of one born deaf and dumb in Paris, whose ears have 
at last attained to the performance of their function, that he 
has now learned the French language (for it is from the court 
of France that he was summoned not long since), and that he 
could say very curious things about the conceptions he had in 
his former condition and about the change of his ideas when 
he commenced to exercise the sense of hearing. These per- 
sons born deaf and dumb can go farther than we think. 
There was one in Oldenburg in the time of the last Count 
' who became a good painter, and showed himself very rational 
in other respects. A very learned man, a Breton by nation, 
told me that at Blainville, about ten leagues from K'antes, 
belonging to the Duke of Rohan, there was, about 1690, a 
poor man, who lived in a hut near the castle outside of the 
town, who was born deaf and dumb, and who carried letters 
and other things to the town and found the houses, following 
some signs which the persons accustomed to employ him 
made him. Finally the poor man became blind also, but did 
not give up rendering some service and carrying letters into 
the town to whatever place they indicated to him by touch. 
He had a board in his hut which, extending from the door to 
the place where his feet were, informed him by its motion 
when any one entered his house. j\Ien are very negligent in 



CH. IX] ON HUMAN UNDERSTANDING 141 

not obtaining an exact knowledge of the modes of thought 
of such persons. If he no longer lives, there is probably 
some one in the vicinity who could still give some information 
respecting him, and make us understand how they showed him 
the things he was to do. But to return to what the man born 
blind, who begins to see, would think of the globe and the 
cube, seeing them without touching them, I reply that he will 
distinguish them, as I have just said, if any one informs him 
that the one or the other of the appearances or perceptions 
which he has of them belongs to the cube or to the globe ; 
but, without this previous instruction, I admit that he will 
not at first venture to think that the kinds of pictures which 
they make of themselves in the depths of his eyes, and which 
might come from a flat picture upon the table, represent the 
bodies, until touch convinces him of the fact, or until, by 
force of reasoning upon the rays of light according to optics, 
he understands by the lights and shades that there is a some- 
thing which arrests these rays of light, and that it must be 
exactly what remains for him in touch, which result he will 
finally reach when he sees this globe and this cube revolve, 
and change the shadows and the appearances in accordance 
with the motion, or even when, these two bodies remaining at 
rest, the light which illumines them changes its place, or his 
eyes change their position. For these are about the means 
we have of distinguishing from afar a picture or a perspec- 
tive, which represents a body, from the body itself. 

§ 11. Ph. [Let us return to perception in general.] It dis- 
tinguishes animals from inferior beings. 

Th. [I am inclined to the belief that there is some percep- 
tion and appetition also in the plants, because of the great 
analogy which exists between plants and animals ; and if, as 
is commonly supposed, there is a vegetable soul, it of necessity 
has perception. Yet I do not cease to attribute to mechanism 
all that takes places in the bodies of plants and animals, 
except their first formation. Thus I agree that the move- 
ment of the plant called sensitive arises from mechanism, and 
I do not approve of having recourse to the soul when the 
question is that of explaining the detail of the phenomena 
of plants and animals.] 

§ 14. Ph. It is true that for myself, indeed, I cannot help 



142 LKIBXITZ'S CRITIQUE OF LOCKE [bk. ii 



believing that even in those kinds of animals which are like 
the oysters and mussels there is some feeble perception ; for 
quick sensations would serve only to discommode an animal 
which is constrained to live always in the place where chance 
has put it, where it is watered with water, cold or warm, pure 
or salt, according as it comes to it. 

Th. [Very well, I also believe that we can say almost as 

" much of plants; but in man's case, his perceptions are accom- 
panied with the power of reflection, which passes to the act 
when there is any occasion. But when he is reduced to a state 
in which he is as it were in a lethargy and almost without 
feeling, reflection and consciousness cease, and universal truths 
are not thought of. But the innate and acquired faculties and 
dispositions, and even the impressions which are received in 

' this state of confusion, do not cease on that account, and are 
not effaced, though they are forgotten. They will even have 
their turn one day in contributing to some notable result, for 
nothing is useless in nature ; all confusion must develop 
itself; the animals even, having attained to a condition of 
stupidity, ought some day to return to perceptions more ele- 
vated ; and, since simple substances always endure, we must 
not judge of eternity by a few years.] 



CHAPTER X 

OF RETEXTION 

§§ 1, 2. Ph. The other faculty of the mind, by which it 
advances farther toward the knowledge of things than by sim- 
ple 2^erception, is that which I call retention, which conserves 
the knowledge received by the senses or by reflection. Reten- 
tion works in two ways : in actually conserving the present 
idea, which I call contemplation ; and in preserving the power 
to bring them again before the mind, and this is what is called 
memory. 

Th. [One retains also and contemplates innate knowledge, 
and very often one cannot distinguish the innate from the 
acquired. There is also a perception of images — either those 



CH. XI] ON HUMAN UNDERSTANDING 143 



which have already existed for some time, or those which are 
formed anevv in us.] 

§ 2. Ph. But you believe with us that these images or ideas 
cease to be anything as soon as they are not actually matters 
of consciousness ; and that to say that there are ideas reserved 
in the memory means at bottom only that the soul has in some 
instances the power of reviving the perceptions it has already 
had with a feeling which at the same time convinces it that it 
has previously had these kinds of perceptions. 

Th. [If ideas were only forms or modes of thoughts, they 
would cease with them; but you yourself have admitted, sir, 
that they are internal objects, and in this way can subsist. 
And I am astonished that you can always be satisfied with 
these naked powers or faculties, which you would apparently 
reject in the scholastic philosophers. It would be necessary 
to explain a little more distinctly in what this faculty consists 
and how it is exercised ; and that would make known that 
there are dispositions which are the remains of past impres- 
sions in the soul as well as in the body, but of which we are 
conscious only when the memory finds some occasion for them. 
And if nothing restored past thoughts, as soon as we no longer 
think of them, it would be impossible to explain how the 
memory can preserve them ; and to recur for this purpose to 
this naked faculty is to speak nowise intelligibly. 



CHAPTER XI 

OP DISCERNMENT OR THE FACULTY OF DISTINGUISHING IDEAS 

§ 1. Ph. Upon the faculty of distinguishing ideas depends 
the evidence and certainty of several propositions which pass 
for innate truths. 

Th. I admit that to think of these innate truths and to 
unravel them discernment is necessary ; but they do not on 
that account cease to be innate.] 

§ 2. Ph. Now, vivacity of mind consists in recalling 
promptly ideas ; but judgment in representing them clearly 
and distinguishing them exactly. 



in LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

Th. [IVrliaps cacli is vivacity of imagination, and judg- 
ment consists in the examination of propositions according to 

IVJISOU.] 

Ph. [I am not averse to this distinction of mind and judg- 
ment. And sometimes there is judgment in not employing it 
too much. For example : to examine certain witty thoughts 
by the severe rules of truth and good reasoning is in a certain 
sense an insult. 

Til. [This remark is a good one ; witty thoughts must have 
at least some apparent foundation in reason, but it is not 
necessary to examine them minutely with too much scrupu- 
lousness, as it is not necessar}^ to look at a picture from a 
position too near it. It is in this, it seems to me, that 
Father Bouhours fails more than once in his Art cle penser 
dans les ouvrages cC esprit^ as when he despises this sally of 
Lucan : ^ 

Victrix causa diis placuit, sed victa Catoni. 

§ 4. Ph. Another operation of the mind in respect to its 
ideas is the comparison it makes of one idea with another as 
regards extension, degrees, time, place, or some other circum- 
stance ; it is upon this that the great number of ideas com- 
prised under the term relation depends. 

Th. [According to my view, relation is more general than 
comparison, for relations are either of comparison or of concur- 
rence. The first concern the congruity or incongruity (I take 
these terms in a less extended sense) which comprises resem- 
blance, equality, inequality, etc. The second comprise some 
connection, as that of cause and effect, of whole and parts, of 
position and order, etc.] 

§ 6. Ph. The composition of simple ideas, for the purpose 
of making complex ideas, is also an operation of our mind. 
We may refer to this the faculty of extending ideas by uniting 
those of the same kind, as in forming a dozen from several 
units. 

Th. [The one is doubtless as much composition as the 

1 Dominique Bouhours, 1628-1702, one of the ablest masters of the French 
language in the seventeenth century. The title of his work here given follows 
Gerhardt's text. The correct title is: Maniere de bien pettser da)is les 
ouvrages d' esprit, Paris, 1687. There were several editions. — Tr. 

2P7iars. 1,128. — Tr. 



CH. xi] ON HUMAN UNDERSTANDING 145 



other ; but composition of similar ideas is simpler than that of 
different ideas.] 

§ 7. Ph. A dog will nurse young foxes, will play with 
them, and will have for them the same fondness as for her 
own puppies, if they can be made to suck her so long as is 
needful for the milk to spread through their entire body. 
Moreover it does not appear that animals, who have a large 
number of young at once, have any knowledge of their num- 
ber. 

Th. [The love of animals arises from a pleasure which is 
increased by habit. But as for the precise number, men even 
can know the numbers of things only by some skill, as in using 
numerical names in order to count, or figural arrangements 
which make them know at once without counting if anything 
is wanting.] 

§ 10. Ph. Animals do not form abstract thoughts. 

Tli. [I agree. They apparently recognize whiteness, and 
notice it in the chalk or the snow ; but this is not yet abstrac- 
tion, for that demands a consideration of what is common, 
separated from what is particular, and consequently there 
enters into it the knowledge of universal truths, which is not 
given to the animals. It is well said also that the animals 
which speak do not use words to express general ideas, and 
that men deprived of the use of speech and of words do not 
cease to invent other general signs. I am pleased also to see 
that you here and elsewhere so well observe the advantages of 
human nature.] 

§ 11. Ph. If animals have some ideas, and are not pure ma- 
chines, as some maintain, we cannot deny that they have reason 
in a certain degree, and, for myself, it appears as evident that 
they reason as that they feel. But it is only upon particular 
ideas that they reason according as their senses represent these 
ideas to them. 

Th. [Animals pass from one imagination to another by the 
connection which they have felt here before ; for example, when 
his master takes a stick, the dog fears a whipping. And in 
many instances children with the rest of mankind proceed 
nowise differently in their passages from thought to thought. 
This might be called consecution and reasoning in a very broad 
sense. But I prefer to conform to the received usage in conse- 



146 LEIBNITZ'S CRITIQUE OF LOCKE Iuk. n 



crating these terras to man and in limiting them to the knowl- 
edge ot some reason of the connection of perceptions, which 
sensations alone cannot give ; their effect being only to cause 
us naturally to expect at another time this same connection 
which we have noticed before, although perhaps the reasons 
are no longer the same, a fact which often deceives those who 
are governed only by the senses.] 

§ 13. Ph. Idiots lack vivacity, activity, and movement in 
the intellectual faculties, whereby they are deprived of the use 
of reason. Madmen seem to be at the opposite extreme, for it 
does not appear to me that these latter have lost the power to 
reason, but having wrongly united certain ideas, they take 
them for truths, and deceive themselves in the same way as 
those Avho reason justly upon false principles. Thus you will 
see a madman who thinks he is king maintaining by a just 
consequence that he should be served, honored, and obeyed 
according to his rank. 

Th. \_Idiots do not exercise reason, and they differ from some 
stupid persons who have good judgment, but, not having prompt 
conception, they are despised and disturbed as he would be 
who wished to play ombre with persons of distinction and 
thought too long and too often of the part he must take. I 
remember a learned man who, having lost his memory by the 
use of certain drugs, was reduced to this condition, but his 
judgment alwaj^s appeared. A man wholly mad lacks judg- 
ment on nearly every occasion ; but the vivacity of his imagi- 
nation may make him agreeable. But there are particular 
madmen who make a false supposition at an important point 
in their lives, and reason justly thereupon, as you have well 
said. There is such a man, well known at a certain court, 
who believes himself destined to redress the affairs of the 
Protestants and to bring France to reason, for which purpose 
God caused the greatest personages to pass through his body 
in order to ennoble it ; he desires to marry all the princesses 
he sees to be marriageable, but after having made them hoi}', 
in order to have a holy progeny who are to rule the land ; 
he attributes all the misfortunes of war to the little attention 
paid to his advice. In speaking with a certain sovereign, 
he takes every necessary measure not to lower his dignity. 
When they enter into conversation with him, he maintains 



CH. xii] ON HUMAN UNDERSTANDING 147 

himself so well that I have doubted more than once whether 
his madness is not feigned, for he is not inconvenienced by 
it. However, those who know him more intimately assure me 
that his madness is wholly genuine.] 



CHAPTER XII 

OF COMPLEX IDEAS 

PJi. The understanding bears not a little resemblance to 
a room wholly dark, which has only certain small openings to 
let in from outside exterior and visible images, so that if these 
images, coming to be painted in this dark room, could remain 
there and be placed in order, so that they could be found upon 
occasion, there wou.ld be a great resemblance between this 
room and the human understanding. 

Th. [To make the resemblance greater, you should suppose 
that in this room there was a canvas to receive the images, not 
even, but diversified by folds, representing the (kinds of) in- 
nate knowledge ; further, that this canvas or membrane being 
stretched would have a kind of elasticity or power of action, 
and also an action and reaction accommodated as much to the 
past folds as to the newly arrived kinds of impressions. And 
this action would consist in certain vibrations or oscillations, 
such as are seen in a stretched string so touched that it gives 
forth a kind of musical sound. For not only do we receive 
images or outlines in the brain ; but we form besides new ones, 
when we look at complex ideas. Thus the canvas that repre- 
sents our brain is necessarily active and elastic. This com- 
parison would explain tolerably well what passes in the brain ; 
but as for the soul, which is a simple substance or moyiad, it 
represents without extension these same varieties of extended 
masses and perceives them.^] 

§ 3. Ph. Now complex ideas are either modes or substances 
or relations. 

1 According to the principle of Pre-established Harmony. Cf. Systeme 
nouveau de la nature, etc., 1(J95, §§ 14, 15; Gerhardt, 4, 484, 485; Erdmaun, 
127, 128; Jacques, 1, 475, 476; translation. Appendix, p. .— Tk. 



148 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



Th. [This division of the objects of our thought into sub- 
stances, modes,' and rehations is sufficiently to my taste. I be- 
lieve that qualities are only modifications of substances, and 
that the understanding adds thereto the relations.- From this 
follows more than you think.] 

Ph. Modes are either simple (as a dozen, a score, which are 
composed of simple ideas of the same kind, i.e. of units) or 
mixed (as beauty), into which enter simple ideas of different 
kinds. 

Th. Perhaps dozen or score are only relations, and are con- 
stituted only in connection with the understanding. Units are 
separate, and the understanding gathers them together how- 
ever dispersed they be. Yet, although relations are from the 
understanding, they are ndC groundless or unreal. For in the 
first place understanding is the origin of things ; and indeed 
the reality even of all thiJfigs, simple substances excepted, ulti- 
mately consists only of perceptions of the phenomena of sim- 
ple substances. It is often the same with regard to the mixed 
modes ; i.e. it is necessary to refer them rather to the rela- 
tions.] 

§ 6. Ph. The ideas of substances are certain combinations of 
simple ideas, which are supposed to represent particular and 
distinct things, subsisting by themselves, among which ideas 
the obscure notion of substance, . which is assumed without 
knowing what it is in itself, is always considered as the first 
and chief. 

TJi. [The idea of substance is not so obscure as you think. 
You can know what it ought to be, and what it knows of itself 
in other things ; and indeed the knowledge of the concrete 
always precedes that of the abstract; the hot (thing) rather 
than the heat.] 

§ 7. Ph. In regard to substances there are also two kinds of 
ideas: the one of single substances, like that of a man, or a 
sheep; the other of several substances joined together, as of 
an army of men, or a flock of sheep. These collections form 
also a single idea. 

1 Cf. Descartes, Prin. Philos.. I., § 56; Veitch's translation, 8th ed., p. 217; 
Spinoza, Ethica, Pt. I., Def. 3; Elwes' translation, Vol. 2, p. 46; Locke, Essay, 
Bk. IL, chap. 12, § 4, Vol. 1, p. 280 (Bohn's ed.). — Tr. 

2 Cf. Leibnitz, Neio Essays, Bk. II., chap. 30, § 4. — Tr. 



CH. xiii] ON HUMAN UNDERSTANDING 149 

Til. [This unity of the idea of aggregates is very true ; but 
ultimately you must admit that this collective unity is only a 
congruity or relation, whose ground- is in that which is found 
in each of the single substances separately. Thus these beings 
by aggregation have no other completed unity than the mental; 
consequently their entity also is in some mental shape or phe- 
nomenon, as that of the rainbow.] 



CHAPTER XIII 

OF SIMPLE MODES, AND FIRST OF THOSE OF SPACE 

§ 3. Ph. Space considered with respect to the length which 
separates two bodies is called distance; with respect to length, 
breadth, and depth it may be called cajKicity. 

Th. [To speak more distinctly, the distance between two 
fixed things (be they points or extensions) is the length of the 
shortest possible line that can be drawn from one to the other. 
This distance may be considered absolutely or in a certain 
figure which comprises the two distant things. For example, 
the straight line is absolutely the distance between two points. 
But these two points, being in the same spherical surface, the 
distance of these two points in this surface is the length of 
the shortest great arc of a circle, which may be drawn from 
one point to the other. It is well also to notice, that distance 
is not only between bodies, but also between surfaces, lines, 
points. It may be said that the cwpacity or rather the intervcd 
between two bodies or two other extensions, or between an 
extension and a point, is the space constituted by all the 
shortest lines which may be drawn between the points of each. 
This interval is filled, exce])t when the two fixed things are 
in the same surface, when the shortest lines between the 
points of the fixed things must also fall in this surface or 
must there be expressly formed.] 

§ 4. Ph. Besides that which is in nature, men have estab- 
lished in their minds the ideas of certain determinate lengths, 
as an inch or a foot. 

Th. [They cannot do it. For it is impossible to have the 



160 



LEIBNITZ'S CKITIQUE OF LOCKE [bk. ii 



idea of a precisely detennined length. You can neither say 
nor understand by the mind what an inch or a foot is. And 
you can preserve the meaning of these terms only by real 
measures, which you suppose unchanging, by means of which 
you can always recover them. Thus Mr. Greaves,^ an Eng- 
lish mathematician, desired to make use of the pyramids of 
Egypt, which have endured a long time and will endure appar- 
ently some time longer, to conserve our measures, by showing 
posterity the propositions ^ which have been sketched in defi- 
nite lengths in one of these pyramids. It is true that a little 
after it was discovered that pendulums serve to perpetuate 
measures {mensuris rerum ad posteros transmittendis) , as Huy- 
gens," jNIouton,* and Buratini, formerly maistre de monnoye in 
Poland, have demonstrated ^ by showing the proportion of our 
measures of length to that of the pendulum, which beats pre- 
cisely a second (for example), i.e. the 86400th ^ part of a 
revolution of the fixed stars, or of an astronomical day ; and 
Buratini has composed a treatise expressly thereupon, which 

1 John Greaves, 1602-1652, Savilian Professor of Astronomy at Oxford, 
1(>43-1648. His Pyramidoyraphia, or a Discourse on the Pyramids in Eyypt, 
1646. — Tk. 

2 Gerhardt and Erdmann read: "propositions"; Jacques reads: "propor- 
tions " ; Sehaarschmidt translates " Verhaltnisse." — Tr. 

3 Christian Huygens, 1629-1695, a Dutch physicist, geometer, and astronomer. 
He discovered the laws of double refraction, and was the first to establish on 
a sure foundation the wave theory of light, in his Traite de la lumiere; 
Leyden, 1690. His researches in physical optics constitute his chief claim to 
scientific immortality. His application of the pendulum to regulate the move- 
ment of clocks, arising from his felt need of an exact measure of time in 
astronomical observations, dates from 1656. He published his Description 
de I'horloge a pendicle in 1657, and presented his first "pendulum-clock" to 
the States-General June 16, 1657. This Description was republished as chap. 1 
of his magnum opus, the Horologiuin oscillatorium, sive de motu pendulorum 
ad horologia adaptato, dedicated to Louis XIV., March 25, 167-3. In chap. 4 of 
this work he determined the centre of oscillation of a pendulum, and conse- 
quently the length of the simple i.sochronous pendulum. His works were 
published in two vols. 4to, Opera varia, Leyden, 1724, and two supplementary 
vols. 4to, Opera reliqua, Amsterdam, 1728. — Tr. 

4 Galjriel Mouton, 1618-1694, a French mathematician and astronomer, 
principally known by his Observationes diametrorum solis et lunx apparen- 
tium, Lyons, 1670. His principal title to honorable mention in the history 
of science is the invention of the method of differences for the calculation of 
tables of every kind, afterwards reduced to a system by Sir Isaac Newton, 
1642-1727, and known by us as our method of interpolation. — Tr. 

5 Erdmann and Jacques read : " pretendu montrer," i.e. claimed to demon- 
strate. — Tr. 

6 Erdmann and Jacques read : " 864,000th," evidently an error. — Tr. 



CH. xm] ON HUMAN UNDERSTANDING 151 

I have seen in mauuscript. But there is, however, this imper- 
fection in this measure of pendulums, wliich must be limited 
to certain countries, for pendulums to beat in the same time 
need to be shorter at the equator. And it is furthermore 
necessary to assume the constancy of the really fundamental 
measure, viz. : the length of a day or of a revolution of the 
globe of the earth around its axis, and also of the cause of 
gravitation, not to speak of other circumstances.] 

§ 5. Ph. Observing how extremities are terminated either 
by straight lines which form distinct angles, or by curved lines 
in which no angle can be perceived, we form the idea ol figure. 

Th. [A superficial figure is terminated by a line or by lines : 
but the figure of a body can be limited without determined 
lines, as for example that of a sphere. A single straight line 
or plane surface cannot enclose any space or make any figure. 
But a single line can enclose a superficial figure, for example 
the circle, the oval, as also a single curved surface can enclose 
a solid figure, like the sphere and the spheroid. Yet, not only 
several straight lines or plane surfaces, but also several curved 
lines or several curved surfaces, can concur together and form 
even angles between themselves, when the one is not the tan- 
gent of the other. It is not easy to give the definition of figure 
in general according to the usage of geometers. To say that it 
is a limited extension would be too general, for a straight line, 
for example, although terminated by the two ends, is not a 
figure and even two straight lines cannot make one. To say 
that it is an extension limited by an extension is not general 
enough, for the entire spherical surface is a figure and yet it is 
not limited by any extension. It may be said, however, that 
figure is a limited extension, in which there are an infinite num- 
ber of paths from one point to another. This definition com- 
prises limited surfaces without terminating lines which the 
preceding definition did not comprise, and excludes the lines, 
because from one point to another in a line there is only one 
path or a determined number of paths. But it will be still 
better to say that figure is limited extension, which may admit 
an extended section, or better which has breadth, a term which 
hitherto had not been further defined.] 

§ 6. Ph. At the least all figures are only simple modes of 
space. 



152 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



Th. [According to your view, the simple modes repeat the 
same idea, but in figures there is not always the repetition of 
the same mode. Curves differ much from straight lines and 
between themselves. So I do not know how the definition of 
the simple mode will be in place here.] 

§ 7. Ph. [We need not take our definitions too strictly. 
But let us pass from figure to place.'] When we find all the 
pieces upon the same squares of the chess-board where we left 
them, we say that they are all in the same place, although per- 
haps the chess-board has been moved. We say also that the 
chess-board is in the same place, if it remains in the same part 
of the cabin of the vessel, although the vessel has sailed. The 
vessel is also said to be in the same place supposing it 
keeps the same distance with reference to the parts of the 
neighboring countries, although the earth has perhaps turned 
round. 

Til. \_Place is either particular when considered with regard 
to certain bodies, or universal when it relates to all, and with 
reference to which all the changes possible in relation to any 
body are taken into account. And if there were nothing fixed 
in the universe, the place of each thing could still be deter- 
mined by reasoning,^ if there were means of making a record of 
all the changes, or if the memory of a creature could suffice for 
them, as they say, the Arabs play chess by memory and on 
horseback. What we cannot understand, however, is neverthe- 
less determined in the truth of things.] 

§ 15. Ph. If any man asks me what space is, I am ready to 
tell him when he tells me what extension is. 

Th. [I wish I could speak of the nature of fever or any other 
malady with the same certainty with which I believe the nature 
of space is expounded. Extension is the abstract of the ex- 
tended. Xow the extended is a continuum whose parts are 
coexistent, or exist at the same time.] 

§ 17. Ph. If any one asks whether space without body is 

1 Schaarsclimidt says that the statements here made hy Leihuitz liave since 
found their confirmation and accomplishment through Gauss' Theoria motus 
corporurn coelestium. The work was puhlished at Hamburg, in 180i), and 
"gave a powerful impulse to the true methods of astronomical observation." 
The author, Carl Friedrich Gauss, 1777-185.5, was an eminent German mathe- 
matician. His collected works, edited by E. J. Schering, have l)een published 
by the Royal Society of Giittingen, 7 vols.,4to. Gottingen: 1803-1871. — Tr. 



xin] ON HUMAN UNDERSTANDING 153 



substance or accident, I should reply without hesitation that I 
know nothing about it. 

Til. [I fear you may think me vain in wishing to determine 
Avhat you, sir, admit you do not know. But if it is expedient 
to judge, (I fear) that you know more about the matter than 
you state or think you do. Some have believed that God is 
the place of things.^ Lessius and Guericke, if I am not mis- 
taken, were of this opinion, but then place contains something 
more than what we attribute to the space which we deprive of 
all activity ; and in this way it is no more a substance than 
time, and if it has parts it cannot be God. It is a relation, an 
order, not only between existences, but also between possibili- 
ties as they may exist. But its truth and reality, like all 
eternal truths, is grounded in God.] 

Ph. [I am not far from your view, and you know the pas- 
sage of St. Paul, who says that we live and move and have 
our being in God.^ Thus, according to different ways of con- 
sidering the matter, it may be said that space is God, and also 
that it is only an order or a relation.] 

Th. [The better statement then will be that space is an 
order, but that God is its source.] 

§ 18. Ph. [Yet to know whether space is a substance, it 
would be needful to know in what the nature of substance in 
general consists. But in this there is a difficulty. If God, 
finite spirits, and bodies participate in common in an identical 
substantial nature, would it not follow that they differ only as 
different modifications of this substance ?] 

1 This doctrine appeared very early. Schaarschmidt refers to tlie collection 
of poems of nncertaiu origin called Orphica, where (Fragt. vi.,p. 457, ed. Her- 
matm, v. 8 and 9) it is poetically expressed thus : " All that has heen and here- 
after will be, is formed together in the hosom of Zeus." Again (v. 17-20) : 
"One is the ruling Being, in whom the All moves, fire, water, earth and air, 
day and night, reason, the first principle and joyful love — all this lies in the 
great bosom of Zeus," etc. Malebranche rejiresents a phase of the same view 
in his doctrine that we see all things iu God. Cf. his De la Eecherche de la 
Verit.e, III., ii., 6: "We abide thus in the view that God is the intelligible 
world or the place of spirits, just as the material world is the place of bodies. 
From His power they receive all their modifications, in His wisdom they find 
all their ideas, by His love they are moved in all tlieir moral inclinations. But 
because His power and His love are nothing else than Himself, we will believe 
with St. Paul, that He is not far from any one of us, and that iu Him we live 
and move and have our being." Cf. also James Martineau, Types of Ethical 
Theory, 2d ed., Vol. 1, p. 170 sq. New York: Macmillan & Co., lS8(i. — Tr. 

2 Acts 17 :28.— Tr. 



]f,4 LEIBNITZ'S CRITIQUE OF LOCKE [kk. ii 



Th. [If this result follows, it would follow also, that God, 
liuite spirits, and bodies, participating in common in an iden- 
tical nature of being, would differ only as different modifica- 
tions of this being.] 

§ 19. Ph. Those who first thought of regarding accidents as 
a kind of real beings, which need something in which to inhere, 
wore constrained to invent the word substance to serve as a 
support to the accidents. 

Th. [Do you then think, sir, that the accidents can subsist 
apart from the substance ? or do you mean that they are not 
real beings ? You seem to multiply difficulties without reason, 
and I have remarked above that substances or concretes are 
conceived rather than accidents or abstracts.] 

Ph. The words substance and accident are in my view of 
little use in philosophy. 

Th. [I admit that I am of another opinion, and I believe 
that the consideration of substance ^ is one of the most important 
and fruitful points of philosophy.] 

§ 21. Ph. [We have now spoken of substance only by the 
way, while asking if space is a substance. But it is sufficient 
for us that it is not a body.] No one will dare to make body 
infinite like space. 

Th. [Descartes and his followers have said, nevertheless, 
that matter has no limits, in making the world indefinite, so that 
it is not possible for us to conceive of its extremities. And 
they have changed the term infinite into indefinite with some 
reason ; for there never is an infinite whole in the world, 

1 Cf. New Essays, Bk. II., chap. 23, § 2; De primie pMlosfiphiie emenda- 
tione et de notione substantias, 1(394, Gerhardt, Vol. 4, pp. 4<J8-470; Erdmann, 
pp. 121-122; A. Jacques, (Euvres de Leibniz, Vol. 1, pp. 452-454 (in French) ; 
translation. Appendix, pp. ; Systeme nouveau de la nature et de la 

communication des substances, aussi bien que de l' union qu'il y a entre Vdme 
et le corps, 1695, §§ 2, 3, Gerhardt, Vok 4, pp. 477 sq. ; Erdmann, pp. 124^128; 
Jacques, Vol. 1, pp. 469 sq.; translation. Appendix, pp. ; Be ipsa 

natura, sive de vi insita actionibusque creaturum, 1698, Gerhardt, Vol. 4, pp. 
504-516 ; Erdmann, pp. 154-160 ; Jacques, Vol. 1, pp. 455-468 (in French) ; trans- 
lation. Appendix, pp. ; Considerations sur le princijye de vie et sur 
les natures plastiqiies, 1705, Gerhardt, Vol. 6, pp. 539-546; Erdmann, pp. 
429-4.32; translation, Duncan, Philos. Works of Leibnitz, pp. 1(53-169; Prin- 
cipes de la nature et de la grace fond^s en raison, c. 1714, Gerhardt, Vol. 6, 
pp. 598-606; Erdmann, pp. 714-718; translation, Duncan, op. dt.. pp. 209-217: 
La Monadologie, 1714, Gerhardt, Vol. 6, pp. 607-623 : Erdmann, pp. 705-712; 
translation, Duncan, op. cit., pp. 218-232 ; also F. H. Hedge, in " The Jour. Spec. 
Philos.," Vol. 1, pp. 129-137. — Tr. 



CH. XIV] ON HUMAN UNDERSTANDING 155 



altliougli there are always some wholes greater than others to 
infinity, and the universe even cannot pass for a whole as I 
have elsewhere ^ shown. 

Ph. Those who take matter and extension as one and the 
same thing maintain that the inner sides of a hollo^v vacuous 
body would touch. But the space which is between two bodies 
suffices to prevent their mutual contact. 

Th. [I am of your opinion, for although I do not admit a 
vacuum, I distinguish matter from extension, and I admit that 
if there were a vacuum in a sphere, the opposite poles in the 
hollow space would not on that account touch. But I believe 
that this is a case which the divine perfection does not allow.] 

§ 23. Ph. It seems, however, that motion proves a vacuum. 
When the least part of the divided body is as large as a grain 
of mustard-seed, a void space equal to the size of a grain of 
mustard is requisite in order to make room for the parts of 
this body to move freely ; the same condition will hold good 
when the parts of the matter are one hundred million times 
smaller. 

Th. [It is true, that if the world were full of hard corpus- 
cles, which could neither yield nor divide, as the atoms are, 
depicted, motion would be impossible. But in truth, there is no ' 
original hardness ; on the contrary, fluidity is the original 
condition, and bodies are divided as needful, since there is 
nothing to prevent it. This takes away all the force in the 
argument for a vacuum drawn from motion.] 



CHAPTER XIV 

OF DURATION AND ITS SIMPLE MODES 

§ 10. Ph. To extension corresponds duration. And a part 
of duration in which we remark no successions of ideas we 
call an instant. 

Th. This definition of an instant ought (I believe) to mean 
tlie popular notion, like that which the common people have 

1 Cf. ante, pp. 16, 17; also New Esscnj.% Bk. II., chap. 17, § 1. The proof that 
the universe is not, strictly speaking, a wliole, is s^iven in the letter to Des 
Bosses, March 11, 170G, Gerhardt, Vol. 2, p. 304 sq., Erdniann, pp. 4.'55-4;i(J. — Tr. 



i:,G LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

of a point. For strictly the point and the instant are not 
parts of time or space, neither have they parts. They are 
extremities only. 

§ 1(). Ph. It is not motion, but a constant succession of 
ideas which gives us the idea of duration. 

Th. [A succession of perceptions awakes in us the idea of 
duration, but it does not make it. Our perceptions never have 
a succession sufficiently constant and regular to corresjjond to 
that of time, which is a continuum uniform and simple, like a 
straight line. Changing perceptions furnish us the occasion 
for thinking of time, and we measure it by uniform changes. 
But were there nothing uniform in nature, time could not be 
determined, as space likewise could not be determined if there 
were no fixed or immovable body. So that knowing the rules 
of different motions, we can always refer them to the uniform 
intelligible motions, and see beforehand by this means what 
will happen through the different motions taken together. 
And in this sense time is the measure of motion, i.e. uniform 
motion is the measure of non-uniform motion.] 

§ 21. Ph. Xo two parts of duration can certainly be known 
to be equal; [and you must admit that observations can attain 
only approximate equality.] After exact research the dis- 
covery has been made that there is really an inequality in the 
diurnal revolutions of the sun, and we do not know but that 
the annual revolutions are unequal also. 

Th. [The pendulum has made us realize and see the in- 
equality of the days from one noon to another : Solem dicere 
falsiim audet. It is true that men knew this already, and that 
this inequality has its rules. As for the annual revolution, 
which makes good the inequalities of solar days, it may change 
in the course of time. The revolution of the earth about its 
axis which is commonly attributed to the x>rimum mobile,^ is our 
best measure up to the present time, and clocks and watches 
serve to divide it for us. Furthermore this same daily revolu- 

1 In Aristotle's philosophy, rh np^rov ki.-oOi', i.e. God, who, himself unmoved, 
is the necessary first and unceasing source of the eternal movement of the uni- 
verse. Cf. Metaphys., A, G-10, 1071 sq.; Phys., \^^., 0,258'' 10: also Zeller, 
Outlines, § 56, 3, and Die Philos. d. Griech., 3d ed., 1879, Vol. 4, p. 358; 
Wallace, Outlines of the Philos. of Aristotle, 3d ed., § 39; Hegel, Gesch. d. 
Philos., 2d ed., Vol. 2, p. 289 sg.; Benn, The Greek Philosophers, Vol. 1, pp. 
348-350. — Tr. 



cii. xiv] ON HUMAN UNDERSTANDING 157 

tion of the earth may also change in the course of. time: and 
if any pyramid could endure long enough, or if we should build 
new ones we could perceive it by observing there the length of 
pendulums a known number of whose beats occurs now during 
this revolution ; we could also know in some way the change 
by comparing this revolution with others, as with those of 
Jupiter's satellites, for it is not apparent that, if there is any 
change in one or the other, it will always be proportional. 

Ph. Our measure of time would be more exact if we could 
preserve a past day in order to compare it with the days to 
come, as we preserve the measures of space. 

Th. [But instead of that we are reduced to preserving and 
watching bodies which move in nearly equal times. Also we 
cannot say that a measure of space, as for example, an ell 
which is preserved in wood or metal remains perfectly the 
same.] 

§ 22. Ph. Now since all men manifestly measure time by 
the motion of the heavenly bodies, it is very strange that one 
is not permitted to define time as the measure of motion. 

Th. [I just stated (§ 16) how that should be understood. It 
is true that Aristotle saysHhat time is the number and not the 
measure of motion. And in fact, it may be said that duration 
is known by the number of periodic equal motions of which 
one begins when another ends, for example, by so many revolu- 
tions of the earth or the stars.] 

§ 24. Ph. Nevertheless to anticipate these revolutions and 
say that Abraham was born in the year 2712 of the Julian era, 
is to speak as unintelligibly, as if you counted from the begin- 
ning of the world, although you suppose that the Julian era 
commenced several hundred years before there were any days, 
nights, or years marked by any revolution of the sun. 

Th. [This vacuum which may be conceived in time, indicates, 
like that of space, that time and space extend to the possible as 
Avell as to the actual. Besides, of all the chronological methods, 
that of reckoning the years since the beginning of the world is 
the least convenient, although this would be, without touching 
upon other reasons, only because of the great difference exist- 
ing between the Septuagint and the Hebrew text.] 

1 Pln/s., IV., 11, 2inbi, 210b 8; (•/. Wallace, OvtUncs of the Philos. of Arin- 
totlc, M ed., § 44. Wallace quotes the Greek of the first passage here referred 
to. — Tr. 



ir.8 LEIBNITZ'S CKITIQUE OF LOCKE [bk. ii 

§ IT). Ph. One may conceive the beginning of motion, al- 
thongli he may not comprehend that of duration taken in all 
its extension. One may give limits to the body, but cannot do 
it with regard to space. 

Th. [It is as I just said that time and space indicate the 
possibilities beyond the supposition of existences. Time and 
space are of the nature of eternal truths which consider equally 
the possible and the actual.] 

§ 27. Ph. In fact the ideas of time and eternity come from 
the same source, for we can in our thought add certain lengths 
of duration to one another as often as we please. 

Th. [Hut in order to draw from them the notion of eternity, 
it is necessary to think besides that the same reason always 
exists for going farther. It is this rational consideration which 
achieves the notion of the infinite or the indefinite in possible 
progress. Thus the senses alone cannot suffice to cause the 
formation of these notions. And ultimately it may be said 
that the idea of the absolute^ is anterior in the nature of things 
to that of the limits which are added, but we notice the former 
only as we commence with Avhat is limited and strikes our 
senses.] 

CHAPTER XV 

OF DURATION AXD EXPAXSIOX CONSIDERED TOGETHER 

§ 4. Ph. One admits more easily an infinite duration of 
time than an infinite expansion of space, because we conceive 
infinite duration in God, and attribute extension only to matter 
which is finite, and call the space beyond the universe imaginary. 
But (§2) Solomon seems to have other thoughts when, speak- 
ing of Go4r he says : the heaven and the heaven of heavens can- 
not contain Thee;- and for myself I believe that he magnifies 
too highly the capacity of his own understanding who imag- 
ines he can extend his thoughts farther than the place where 
God exists. 

1 Tlie idea of the absolute belongs to our reason as such, cf. New Esmiis, 
Bk. II., chap. 17, § 3, Th., § Ifi. Th., though we first heconie aware of it through 
our consciousness of the particuhir ideas of the reason as limitations of tie 
idea of the absolute. — Tr. 

2 1 Kings 8 : 27 ; 2 Chron. G : 18. — Tr. 



C^ — // 

CH. xvj ON HUMAN UNDERSTANDING 169 

Til. If God were extended, he would have parts. But dura- 
tion grants these only to his works. However in relation to 
space immensity must be attributed to him, which gives also 
parts and order to the immediate works of God. He is the 
source of possibilities as of actualities, of the one by his 
essence, of the other by his will. Thus space like time has 
its reality only from him, and he can fill the void when it 
seems to him good. Thus it is that in this respect he is 
everywhere.^] 

§ 11. Pli. We do not know what relations spirits have with 
space, nor how they participate therein. But we know that 
they participate in duration. 

Th. [All finite spirits are always united to some organic 
body, and they represent to themselves other bodies by means 
of relations to their own. Thus their relation to space is as 
evident as that of bodies. For the rest, before leaving this 
subject, I would add a comparison between time and space to 
those which you have given ; viz. : — if there were a vacuum 
in space (as, for instance, if a sphere were hollow within), you 
could determine its size ; but if there were a vacuum in time, 
i.e. a duration without changes, it would be impossible to 
determine its length. Whence it comes that you may refute 
the one who would maintain that two bodies, between which 
there is a vacuum, touch ; for geometry defends the proposition 
that two opposite poles of a hollow sphere would not touch : 
but you cannot refute the one who would maintain that two 
worlds, the one of which succeeds the other, touch as to dura- 
tion, so that the one necessarily begins when the other ends, 
without the possibility of an interval. You could not refute 
it, I say, because this interval is indeterminable. If space 
were only a line, and if body were immovable, it would no 
longer be possible to determine the length of the vacuum 
between two bodies. 

1 God, according to Leibnitz, is actxia purus, a pure spirit, without body and 
without extension. All other beings require bodies. His onuiipresence is 
dynamic. Cf. Nev) Essays, Bk. H., chap. 1, § 12, Th., ante, p. 113; Letter to 
Des Bosses, Oct. 16, 1706, Gerhardt, Vol. 2, p. 325, Erdmann, p. 440, b. — Tr. 



1,J0 LKIHXirZ'S CRITIQUE OF LOCKE [bk. 



CHAPTER XVI 

OF NUMBER 

§ 4, Ph. In numbers ideas are both more precise and more 
accurately to be distinguished the one from the other than in 
extension, wliere you cannot observe or measure each equality 
and each excess of size as easily as in numbers, because in 
space we cannot by thought attain a certain definite smallness 
beyond which we cannot go, like the unit in number. 

Th. [That should be understood of the integer. For other- 
wise number in its extent., comprising the fraction, the surd, the 
transcendent, and all that may be assumed between two inte- 
gers, is proportional to the line, and there is there as little of 
a minimum as in the continuum. Thus the definition of num- 
ber as a multitude of units is in place only among the integers. 
The precise distinction of ideas in extension does not consist 
in size: for to distinguish size clearly one must have recourse 
to integers, or to other (measures) known by means of inte- 
gers ; thus from continuous quantity it is necessary to recur to 
discrete quantity, in order to have a distinct knowledge of size. 
Thus the modifications of extension, when not joined to- num- 
bers, cannot be distinguished by figure, taking this term so 
generally that it means everything which makes two exten- 
sions dissimilar the one to the other.] 

§ 5. Ph. By repeating the idea of a unit and joining it to 
another unit, we make a collective idea, which we call ttoo. 
And whoever can do that and advance always by adding one 
more to the last collective idea to which he gives a particular 
name, can count so long as he has a set of names and sufiicient 
memory to retain them. 

Th. [By this means alone one cannot advance very far. 
For memory would be too heavily loaded if it must retain an 
entirely new name for each addition of a new unit. That is 
why a certain order and a certain repetition of these names is 
necessary by recommencing in accordance with a certain pro- 
gression.] 

Ph. The different modes of numbers are capable of no other 



CH. xvii] ON HUMAN UNDERSTANDING 161 

difference than that of more or less ; [this is why there are 
simple modes like those of extension.] 

Th. [That may be said of time and of the straight line, but 
not of figures, and still less of numbers, which are not only 
different in size but further unlike. An even number may be 
divided into two equal numbers, but not an uneven. Three 
and six are triangular numbers, four and nine are squares, 
eight is a cube, etc. And this principle has place in numbers 
still more than in figures, for two unequal figures may be per- 
fectly similar to each other, but never two numbers. But I 
am not astonished that you are often deceived thereupon, be- 
cause one does not commonly have a distinct idea of what is 
similar or dissimilar. You see then, sir, that your idea or 
your application of simple or mixed modes is greatly in need of 
correction.] 

§ 6. Ph. [You were right in remarking that it is well to 
give numbers their own names to be retained.] Thus I believe 
that it would be convenient in computation to say a billion for 
brevity's sake instead of a million of millions, and instead of a 
million of millions of millions, or a million of billions, to say 
a trillion, and thus in order to nonillions, for there is little 
need of going farther in the use of numbers. 

Th. These denominations are good enough. Let x=10. 
That posited, a million will be x^, a billion a;'', a trillion x^^, 
etc., and a nonillion x^^. 



CHAPTEE XVII 

OF INFINITY 

§ 1. Ph. One of the most important notions is that of 
the finite and the infinite, which are regarded as modes of 
quantity. 

Th. [Properly speaking, it is true that there is an infinite 
number of things, i.e. that there are always more of them than 
can be assigned. But there is no infinite number, neither line 
nor other infinite quantity, if these are understood as veritable 
wholes, as it is easy to j^rove. The schools have meant or have 
been obliged to say that, in admitting a syncategorematic in- 

M 



102 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

finite,' us they call it, and not a categorematic infinite. The 
true infinite exists, strictly speaking, only in the absolute, which 
is anterior to all composition, and is not formed by the 
additions of parts.^] 

Fit. Wlien we apply our idea of the infinite to the first 
Being, we do it primarily in respect to his duration and ubi- 
quity, and, more figuratively, to his power, his wisdom, his 
goodness, and his other attributes. 

Th. [Not more figuratively, but less immediately, because 
the other attributes make their importance known through 
relation to those into which enters the consideration of 
parts.] 

§ 2. Ph. I thought it was established that the mind regards 
the finite and the infinite as modifications of extension ^ and 
duration. 

Th. [I do not find that it has been established that the con- 
sideration of the finite and the infinite takes place wherever 
there is bulk and magnitude. And the true infinite is not a 
mod[lication, it is the absolute ; on the contrary, when it is 
modified, it is limited and forms a finite.] 

§ 3. Ph. We have believed that since the power of the 
mind to expand without limit its idea of space by new addi- 
tions is always the same, it is thence that the idea of an infi- 
nite space is derived. 

Th. [It is well to add that this is because the same ratio is 
seen always to hold good. Let us take a straight line and 
prolong it until it is double the length of the first. Now it 
is clear that the second line, being perfectly similar to the 
first, may be itself doubled in order to have a third, which is 
still similar to the preceding ; and the same ratio holding 
good always, it is never possible to stop the process ; thus 
the line may be prolonged to infinity, so that the consideration 
of the infinite arises from that of similarity or from the same 
ratio, and its origin is the same with that of universal and 
necessary truths. This shows us how what gives completion 

1 An incompletely defined infinite, capable of or needing still further defini- 
tion, but infinite only so far as it cannot really be defined, the indefinite- 
infinite (infinitum-indefinitum). — Tr. 

■- Cf. ante, pp. 16, IT ; also ^etv Essai/i^, Bk. II., chap. 13, § 21. — Tr. 

3 Locke has: "expansion," Philos. Works, Vol. 1, p. 331 (Bohn's ed.).— 



cii. xvii] ON HUMAN UNDERSTANDING 163 

to the conception of this idea is found in ourselves, and can- 
not come from the experience of our senses, just as necessary 
truths cannot be proved by induction nor by the senses. The 
idea of the absolute is in us internally, like that of being; these 
absolutes are nothing else than the attributes of God, and it 
may be said that they are not less the source of ideas, because 
God is himself the principle of beings. The idea of the abso- 
lute in relation to space, is only that of the immensity of 
God, and so of the others. But you deceive yourself in wish- 
ing to imagine an absolute space which is an infinite whole 
composed of parts ; there is none such, it is a notion which 
implies a contradiction, and these infinite wholes, and their 
opposed infinitesimals, are used only in the calculations of 
geometers, just like the imaginary roots of algebra.] 

§ 6. Ph. [We conceive furthermore a magnitude without 
understanding thereby parts outside of parts.] If to the most 
perfect idea I have of the whitest whiteness, I add another of 
an equal or less brilliant whiteness (for I cannot add the idea 
of a whiter than I have, which I suppose the whitest that I 
actually conceive), it neither increases nor extends my idea in 
any way ; therefore the different ideas of whiteness are called 
degrees.'] 

Th. [I do not fully understand the force of this reasoning, 
for nothing prevents me from receiving the perception of a 
whiter whiteness than what is actually conceived. The true 
reason why we are inclined to believe that whiteness cannot be 
infinitely increased is because it is not an original quality ; 
the senses give us only a confused knowledge of it ; and when 
we have a distinct knowledge of it, we shall see that it arises 
from the structure, and is limited by that of the organ of 
vision. But as regards original or distinctly knowable quali- 
ties, we see that there are sometimes means of going to 
infinity, not only in the case of extension or, if you prefer, 
diffusioyi or what the scholastic philosophy calls partes extra 
partes, as in time and place, but also in the case of intention or 
degrees, for example, as regards velocity.] 

§ 8. Ph. We have no idea of infinite space, and nothing is 
plainer than the absurdity of an actual idea of an infinite 
number. 

Th. [I am of the same opinion. But this is not because we 



l,;i LEIBNITZ'S CRITIQUE OF LOCKE [bk. 



cannot have the idea of the infinite, but because the infinite 
cannot be a true whole.] 

§ l(j. Ph. For the same reason we have then no positive 
idea of an infinite duration or of eternity, any more than of 
innnensity. 

Th. [1 believe we have a positive idea of both, and this 
idea is a true one, provided it is not conceived as an infinite 
whole, but as an absolute or attribute without limits which 
exists in reference to eternity, in the necessity of the existence 
of God, without depending upon parts and without the notions 
being formed b}^ an addition of time. We see furthermore in 
that way, as I have said already, that the origin of the notion 
of the infinite comes from the same source as that of necessary 
truths.] 

CHAPTER XVIII 

OF OTHER SIMPLE MODES 

Ph. There are besides many simple modes formed from 
simple ideas. Such are (§ 2) modes of motion, as sliding, 
rolling; those of sound (§3) which are modified by notes and 
airs, as colors by degrees, not to speak of tastes and smells 
(§6). These always^ have neither measures nor distinct 
names any more than in the case of the complex modes (§ 7), 
because use regulates them, and we will speak of them more 
fully when we come to words. 

Th. [The majority of modes are not sufficiently simple and 
can be reckoned with the complex, for example, to explain what 
sliding and rolling is besides motion, you must consider sur- 
face-resistance.] 

CHAPTER XIX 

OF THE MODES OF THIXKIXG 

§ 1. Ph. [Let us pass from the modes which come from the 
senses to those given us by reflection.] Sensation is, so to 
speak, the actual entrance of ideas into the understanding by 

1 Locke: "ordinarily," Philos. Works, Vol. 1, p. 346 (Bohn's ed.). — Tk. 



cii. xix] ON HUMAN UNDERSTANDING 165 

means of the senses. When the same idea comes again into 
the mind, without the action upon our senses, of tlie external 
object which at first caused it to spring up, the act of the 
mind is called remembrance; if the mind tries to recall it, and 
only after considerable effort finds and brings it to view, it is 
recollection (i-ec\ieiUement) } If the mind looks upon it atten- 
tively for a long time it is contemplation; when the idea floats 
about in the mind without any attention on the part of the 
understanding, it is called reverie. When the mind reflects 
upon ideas, which present themselves, and when it, so to speak, 
registers them in its memory, it is attention ; and when the 
mind fixes itself upon an idea with much application, considers 
it on all sides, and will not be turned aside notwithstanding 
other ideas which come in the way, we call it study or intense- 
ness of thoixght. Slee}) accompanied by no dream is a cessa- 
tion of all these things ; and dreaming is having these ideas in 
the mind while the outer senses are closed, so that they do 
not receive the impressions of external objects with their 
usual quickness. It is, I say, having ideas without any sug- 
gestion from any external objects or known occasion, and 
apart from any choice or determination in any way of the 
understanding. As for that which we call ecstasy, I leave 
others to judge whether it is not dreaming with the eyes open. 
Th. [It is well to clear up these notions and I will try to 
aid in the work. I will say tlien that it is sensation when an 
external object is perceived; that remembrance consists in the 
repetition without the reappearance of the object ; but when 
we know we have had it, it is memory. Recollection (recueille- 
ment) is commonly understood in a sense different from yours, 
viz. : as a state in which we disengage ourselves from things 
in order to apply ourselves to some meditation. But since 
there is no word known to me corresponding to your notion, 
sir, one may apply to it that which you employ. We give 
attention to objects which we distinguish and prefer to others. 
Attention contimiing in the mind, whether the external object 
continues or not, and even whether it is found there or not, is 

1 Cf. below, where the Frencli " recueillement," here employed as a trans- 
lation of the English "recollection," is sliown to have a different meaning 
and nse from that of the English word. As " recueillement " is, however, used 
as an equivalent for the English word, I have translated it in the second para- 
grai^h accordingly. — Tr. 



lUG LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



consideration; which, tending to knowledge without reference 
to action, will be contemi^lation. Attention, whose aim is to 
learn {i.e. the attainment of knowledge for the sake of keep- 
ing it), is study. To consider in order to form a plan is to 
meditate; but reverie appears to be nothing else than following 
certain thoughts for the pleasure one takes therein, with no 
other end ; this is why reverie may lead to madness ; we forget 
ourselves, we forget the die cur hie, we approach dreams and 
chimeras, we build castles in Spain. We can distinguish 
dreams from sensations only because they are not united with 
them, they are like a world apart. Sleep is a cessation of sen- 
sations, and in this way ecstasy is a very deep sleep from which 
one finds difficulty in being awakened, a condition which arises 
from some internal passing cause, which is added in order to 
exclude this profound sleep, arising from some narcotic or 
from some continuous injury to the functions, as in lethargy. 
Ecstasy is sometimes accompanied with visions; but there is 
vision without ecstasy, and vision seems to be nothing but a 
dream wdiich passes for a sensation just as if it acquainted us 
with the truth of objects. And when visions are divine, there is 
actually truth in them, which may be known for instance when 
they contain particular prophecies which the outcome justifies.] 

§ 4. Ph. From the different degrees of intensity^ or relaxa- 
tion of the mind, it follows that thought is the act and not the 
essence of the soul. 

Th. [Doubtless thought is an act and cannot be the essence : 
but it is an essential act, and all substances are of this charac- 
ter. I have shown above that we always have an infinite 
number of little perceptions, without being conscious of them. 
We are never without perceptions, but we are necessarily often 
without a];)perceptions, viz. : when there are no distinct per- 
ceptions. It is from not having considered this important 
point that a relaxed philosophy, as little noble as solid, has 
prevailed with so many excellent minds, and that we have 
hitherto almost ignored that which is most beautiful in the 
soul. This is also the reason why so much probability has 
been found in that error, which teaches that souls are by 
nature perishable.] 

1 Locke has: "iuteutiou aud remission," Philos. Works (Boliii's ed.), Vol. 
1, p. 349. — Tr. 



CH. XX] ON HUMAN UNDERSTANDING 167 

CHAPTER XX 

OF MODES OF PLEASURE AND PAIN" 

§ 1. Ph. As the sensations of the body, like the thoughts 
of the mind, are either indifferent or followed by pleasure or 
pain, the ideas of them cannot be described any more than all 
other simple ideas, nor can the words which serve to designate 
them be defined. 

Th. [I believe that there are no perceptions which are 
wholly indifferent to us, but it is enough that their effect be 
not notable in order that they may be thus spoken of, for 
2)leasure and ^ja('M appear to consist in a notable aid or impedi- 
ment. I admit that this definition is not at all nominal and 
that one may give none at all.] 

§ 2. Ph. The good is that which is fitted to produce and 
increase pleasure in us, or to diminish and cut short some 
pain. Evil is fitted to produce or increase pain in us, or to 
diminish some pleasure. 

Th. [I am also of this opinion. The good is divided into 
the virtuous, the agreeable, and the useful, but ultimately I 
believe that it must be either agreeable itself, or serving some- 
thing else which may give us an agreeable feeling, that is to 
say, the good is agreeable or useful, and virtue itself consists 
in a pleasure of mind.] 

§§ 4, 5. Ph. From pleasure and pain come the passions. 
We have love for that which can produce pleasure, and the 
thought of sadness or of pain that a present or absent cause 
can produce is hatred. But hatred or love which relates to 
beings capable of happiness or misery is often an uneasiness or 
delight which we feel to be produced in us by the considera- 
tion of their existence or of the happiness which they enjoy. 

Th. [I also gave nearly this definition of love when I 
explained the principles of justice, in the preface to my 
" Codex juris gentium diplomaticus," ^ viz. : that to love is to 

1 Tlie Codex juris fjentium diplomaticus, KJO;!, :x collection of public acts 
and treatises, etc. An excerpt from the Preface of this work, entitled Dc no- 
tionibus juris et justitise, is given by Erdmann, pp. ll.S-120; translation, Dun- 
can, Philos. Works of Leibnitz, note 48, pp. 379-382. — Tr. 



1118 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

be inclined to take pleasure in the complete perfection or hap- 
piness of the object loved. And for that reason one neither 
considers nor asks for any other pleasure proper than that 
indeed which is found in the good or pleasure of the one who 
is loved ; but in this sense Ave do not, properly speaking, love 
Avhat is incapable of pleasure or happiness, and we enjoy things 
of this nature without loving them for that reason, unless by 
a prosopopoeia, and as if we imagined that they themselves 
enjoy their perfection. It is not, then, properly love when 
one says that he loves a beautiful picture for the pleasure 
which he takes in feeling its perfections. But it is allowable 
to extend the sense of terms, and their usage varies. Philoso- 
phers and theologians even distinguish two kinds of love, viz. : 
the love which they call the love of complacency, which is 
nothing but the desire or feeling which we have for the one 
who gives us pleasure, without concerning ou^rselves whether 
he receives it; and the love of benevolence, which is the feeling 
that one has for the one who, by his pleasure or happiness, 
gives us some. The first makes us have in view our pleasure 
and the second that of another, but as making or rather consti- 
tuting ours, for if it did not reflect upon us in some way we 
could not concern ourselves with it since it is impossible, 
although they affirm it, to be separated from the good proper. 
And see how it is needful to understand disinterested or non- 
mercenary love, in order to reach a favorable conception of 
nobility and not to fall meanwhile into the chimerical one.] 

§ 6. Ph. The uneasiness (French inquietude) which a man 
feels in himself at the absence of anything which if present 
would give him pleasure is called desire. Uneasiness is the prin- 
cipal, not to say the only stimulus which excites human industry 
and action for whatever good is proposed to man ; if the absence 
of this good is followed by no displeasure or pain, and he who is 
deprived of it can be content and at his ease Avithout its pos- 
session, he does not think of desiring, and less still of making 
any efforts to enjoy it. He feels for this kind of good only a 
bare velleity,^ the term used to signify the lowest kind of desire, 

1 Schaarschmidt translates the French " velleite' " by the German " "Willens- 
nei.scuiif?," i.e. inclination of will. The term is borrowed from the Scholastic 
" velleitas," and is here equivalent to imperfect volition (imperfecta volitio) 
or that condition of the soul in which the will, though not in a state of indiffer- 



CH. XX] ON HUMAN UNDERSTANDING 169 

which approaches nearest to that state in which the soul finds 
itself with regard to anything which is wholly indifferent to 
it, when the displeasure which the absence of anything causes 
is so inconsiderable that it is carried only to feeble longings 
without being compelled to avail itself of the means of obtain- 
ing it. Desire is moreover extinguished or abated by the 
opinion that the wished for good cannot be obtained in propor- 
tion as the soul's uneasiness is cured or allayed by that con- 
sideration. [For the rest, I have found what I stated to you 
about uneasiness in this celebrated English author, whose 
views I often relate to you. I was a little in difficulty as to 
the definition of the English word uneasiness. But the French 
translator ^ whose skill in the fulfilment of this task cannot 
be called in question, remarks at the foot of the page (chap. 
20, § 6,) that by this word the English author understands 
the state of a man not at his ease, the lack of ease and of tran- 
quillity of soul, which in this regard is purely passive, and that 
it must be translated by the (French) word inquietude, which 
does not express exactly the same idea, but approaches it very 
nearly. This caution (he adds) is above all needful with, 
regard to the following chapter, "Of Power," in which the 
author reasons much upon this kind of uneasiness ; for if you 
should not attach to this word the idea which has just been 
indicated, it would be impossible exactly to understand the 
matters treated of in this chapter and which are the most 
important and delicate in the entire work.] 

Th. [The translator is right and the reading of his excellent 
author shoAvs me that this consideration of uneasiness is a capi- 
tal point, in which this author has particularly shown his pene- 
trating and profound mind. For this reason I gave it some 
attention, and after having well considered the matter, it al- 
most appears to me that the (French) word inquietude {restless- 
ness), if it does not express quite the meaning of the author, 
nevertheless sufficiently agrees with the nature of the thing ; 
and that the (English) word uneasiness, if it indicated a dis- 
pleasure, fretfulness (chagrin), inconvenience, in a word some 
effective pain, would not suit his meaning. For I should pre- 

ence, has not as yet sufficient force to pass over into action (volitio). Cf. New 
Essays, Bk. II., chap. 21, § 5 s^., also § 30, Th. — Tb. 
1 M. Pierre (Joste. — Tr. 



170 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

fer to say that in the desire in itself there is rather a disposi- 
tion and preparation for pain than pain itself. It is true that 
this perception sometimes differs from that which is iu pain 
only more or less, but it is the degree which is the essence of 
pain, for it is a notable perception. The same is also seen in 
the difference between appetite and hunger, for when the 
stomach's irritation becomes too strong it is uncomfortable, so 
that we must also apply here our doctrine of perceptions too 
small to be perceived, for if that which goes on in us when we 
have appetite and desire, were great enough, it would cause us 
pain. Hence the infinitely wise author of our being arranged 
it for our good, when he so arranged it that we should often 
be in ignorance and among confused perceptions, in order to 
act more promptly by instinct, and in order not to be disturbed 
by too distinct sensations of a multitude of objects, which do 
not recur immediately and the nature of which could not go on 
to obtain their ends. How many insects we swallow without 
noticing them, how many persons we see who, having a too 
penetrating odor, are annoying, and how many disgusting ob- 
jects Ave should see if our vision were penetrating enough. It 
is also for the sake of this skill that nature has given us the 
stimuli of desire, like the rudiments or elements of pain, or so 
to speak, of semi-pains, or (if you wish to speak extravagantly 
in order to express yourself more forcibly) the little impercep- 
tible pains, in order that we might enjoy the advantage of evil 
without its inconvenience ; for otherwise if this perception 
were too distinct, we would always be miserable while await- 
ing the good, while this continual victory over these semi- 
pains which are felt in pursuing our desire and satisfying in 
some way this appetite, or this longing, gives us a quantity of 
semi-pleasures, whose continuity and mass (as in the continuity 
of the impulse of a heavy body which falls and acquires im- 
petuosity) becomes at last a complete and genuine pleasure. 
And finally, without these semi-pains there would be no pleas- 
ure at all, nor any means of perceiving that something aids 
and relieves us while there are some obstacles which prevent 
us from putting ourselves at ease. It is furthermore in this 
that we recognize the affinity of pleasure and pain which Soc- 
rates in Plato's " Phsedo," ^ noticed when his feet itched. This 
1 P/iKdo, 60 b.— Tr. 



CH. XX] ON HUMAN UNDERSTANDING 171 

consideration of little aids or little releases and imperceptible 
delivei'ances from the fixed tendency, whose result at last is a 
notable pleasure, serves also to give a more distinct knowl- 
edge of the confused idea which we have, and ought to have, of 
lileasiire and of pain ; just as the sensation of heat and of light . 
results from a quantity of little motions which express those 
of objects, as I said above (chap. 9, § 13) and differ from them 
only in appearance and because we ourselves are not conscious 
of this analysis : while many to-day believe that our ideas of 
sense-qualities differ toto genere from notions and from all that 
goes on in objects, and are something primitive and inexpli- 
cable, and indeed arbitrary, as if God made the soul sensible of 
whatever seems good to him, instead of what goes on in the 
body, a view which is far removed from the true analysis of our 
ideas. But to return to uneasiness, that is to say to the little 
imperceptible solicitations which keep us always in suspense; 
these are confused determinations, so that often we do not 
know what we lack, while in the case of the inclinations and 
passions we at least know what we ask for, although confused 
perceptions enter also into their methods of acting, and the 
passions themselves also cause this uneasiness or longing. 
These impulses are like so many little springs which try to 
release themselves, and which make our machine go. And I 
have already remarked above that it is in this way that we are 
never indifferent, when we most appear to be so, for example, 
in turning to the right rather than to the left at the end of a 
path. For the side we take arises from these insensible deter- 
minations, mixed with the actions of objects and the interior of 
the body, which makes us find ourselves more at ease in the one 
or the other manner of bestirring ourselves. The pendulum of 
a clock is called UnrnJie in German, i.e. uneasiness. We may 
say that the same condition exists in our body which can 
never be perfectly at ease ; because if it might be so, a new 
impression of objects, a slight change in the organs, in the ves- 
sels and in the viscera would at once alter the balance and 
cause them to make some slight effort to put themselves again 
in the best state possible : this produces a perpetual strife, 
which causes, so to speak, the uneasiness of our clock, so that 
this appellation is quite to my taste.] 

§ 6. Ph. Joy is a pleasure felt by the soul when it consid- 



LEIBNITZ'S ClUTIQUE OF LOCKE [i-.k. 



ers the possession of a present or future good as assured, and 
we are in jwstiession of a good when it is so in our power that 
we can enjoy it when we wish. 

Th. [Languages hick words sufficiently suitable to distin- 
guish kindred notions. Perhaps the Latin gaudium draws 
nearer this definition of joy than Icetitia, which is also trans- 
lated by the word joy; but then it appears to me to signify a 
state in which pleasure predominates in us, for during the pro- 
foundest sorrow and in the midst of the most poignant grief 
one may take some pleasure as in drinking or hearing music, 
but the unpleasant feeling predominates and so in the midst 
of the most acute pain the mind can be joyful, as in the case 
of the martyrs.] 

§ 8. Ph. Sorroiv is an uneasiness of the soul when it 
thinks of a lost good which it might have enjoyed a longer 
time, or when it is tormented by an actually present evil. 

Th. [Not only the actual presence, but also the fear of 
coming evil may make one sad, so that I believe the definitions 
of joy and sorrow which I have just given agree the better 
with usage. As to uneasiness, there is in pain and consequently 
in sorrow something more : and there is uneasiness even in 
joy, for it makes a man awake, active, full of hope to go farther. 
Joy has been capable of causing death by excess of emotion, 
and then there was in it still more than uneasiness.] 

§ 9. Ph. Hope is the contentment of the soul which thinks of 
the enjoyment which it is destined probably to have in a thing 
suited to give it pleasure. § 10. And fear is an uneasiness 
of the soul, at the thought of a future evil that may happen. 

Th. [If uneasiness signifies trouble I admit that it always 
accompanies fear ; but taking it as this insensible spur which 
pushes us on, it may be applied also to hope. The Stoics 
regarded the passions as thoughts ; thus hope was to them the 
thought of a future good, and fear the thought of a future 
evil. But I prefer to say that the passions are neither satis- 
factions nor displeasures, nor thoughts, but tendencies or 
rather modifications of the tendency, which come from thought 
or feeling and which are accompanied by pleasure or displeas- 
ure.] 

§ 11. Ph. Despair is the thought one has that a good 
cannot be obtained, causing sometimes pain and sometimes 
rest. 



CH. XX] ON HUMAN UNDERSTANDING 173 

Th. [Despair taken as passion is a kind of strong tendency 
wliicli finds itself suddenly arrested, a condition which causes 
a violent struggle and much displeasure. But when despair 
is accompanied with rest and indolence it is rather a thought 
than a passion.] 

§ 12. Ph. Anger is the uneasiness or discomposure we feel 
after having received some injury, and which is accompanied 
with a present desire to avenge ourselves. 

Th. [Anger seems to be something simpler and more gen- 
eral, since animals are susceptible to it to whom no injury is 
done. There is in anger a violent effort tending to annul the 
evil. The desire for vengeance may remain when one is in 
cold blood and has hatred rather than anger.] 

§ 13. Ph. Envy is the uneasiness (displeasure) of the soul 
which arises from the consideration of a good we desire, but 
which another possesses, who in our opinion should not have 
had it in preference to ourselves. 

Th. [According to this notion envy would be always a 
praiseworthy passion and always based upon justice, at least 
in our opinion. But I know not whether men do not often bear 
envy towards recognized merit, which they would not hesitate 
to treat ill, if they had the power. They even bear envy 
toAvards persons regarding a good which they themselves 
would not care to have. They would be content to see them 
deprived of it, without thinking of profiting from their despoil- 
ments, and indeed without being able to hope for it. For 
some good things are like pictures painted in fresco, which can 
be destroyed, but Avhich cannot be taken away.] 

§ 17. Ph. Most of the passions mak6 in many persons 
impressions on the body, and cause therein various changes, 
but these changes are not always sensible ; for example, shame 
which is a felt uneasiness of the soul when it comes to consider 
that it has done something indecent or which may lessen the esti- 
mate others have of us, is not always accompanied by blushing. 

Th. [If men would study to observe more closely the ex- 
ternal movements which accompany the passions, it would be 
difficult to conceal them. As for shame, it is worthy of consid- 
eration that modest persons sometimes feel movemeuts similar 
to those of shame, when they are Avitnesses only of an indecent 
action.] 



174 J.KUkNirZ'S CUITIQUK OF LOCKE [hk. ii 



CHAPTER XXI 

OF POWKK AX1> FREEDOM 

§ 1. Ph. [The mind observing how one thing ceases to be, 
and how another Avhich was not before comes to exist, and 
concluding that there Avill be in the future parallel cases, pro- 
duced by parallel agents, comes to consider in one thing the 
possibility that one of its simple ideas may be changed, and in 
another the possibility of producing that change, and in that 
Avay the mind forms the idea of power.] 

Th. [If jyoioer corresponds to the Latin 2>otentia, it is opposed 
to act, and the passage from poAver to act is change. This is 
Avhat Aristotle understands by the word motion, when he says ^ 
that it is the act or perhaps the actuation of that which is in 
power. It may be said then that power in general is the possi- 
bility of change. Now change or the act of this possibility, 
being action in one subject and passion in another, there 
Avill be two poAvers, one passive, the other active. The active 
may be called faculty, and perhaps the passive might be called 
capacity or receptivity. It is true the active power is sometimes 
taken in a more complete sense, when besides the simple faculty 
there is a tendency ; and it is thus that I take it in my dynamical 
considerations.^ The Avord force might be appropriated to it 
in particular ; and force Avould be either entelechy or effort ; 
for entelechy (although Aristotle takes it so generally that it 
comprises also all action, and all effort) appears to me more 
appropriate to i^r/witYz-ue acting forces, and that of effort to the 
derivative. There is even also a kind of passive p>ower more 
particular and more endoAved Avith reality ; namely, that Avhich 
■ is in matter in which there is not only mobility, Avhich is the 

1 Cf. PJuji<. III., 1, 201«10; Meta-pMjs. K, 9, 1065'' 16. — Tr. 

2 Cf. Be primss philosophise emcndatione, etc., published in the "Acta 
Eruditorum," 161)4, p. 110 «(?., Gerhardt, Vol. 4, pp. 4(!8-470; Erdmanu, i^p. 
121-122 ; Jacques, Vol. 1, pp. 452-454, iu French ; translation, Duncan. Philns. 
Works of Leibnitz, pp. 68-70; also, Beilage.May, 1702, appended l>y Gerhanlt 
to the letter to Fahri, Gerhardt, Leibnizens Math. Schriften, Vol. 6, pp. 98 sq., 
especially p. 101 ; Specimen dynamicum, published in the " Acta Erudi- 
torum," April, 1695, Gerhardt, Leibnizens Math. Schriften, Vol. 6, pp. 234 sq 
— Tr. 



cii. xxi] ON HUMAN UNDERSTANDING 175 

capacity or receptivity for motion, but also resistance, which 
includes impenetrability ^nd inertia. Entelechies, i.e. primitive 
or svibstantial tendencies, when accompanied by perception, are 
souls.] 

§ 3. Ph. The idea of power expresses some kind of relation. 
But what one of our ideas of whatever kind does not include some 
relation? Our ideas of extension, of duration, of number, do 
they not all contain in themselves a secret relation of parts ? 
The same thing is noticed in a still more visible manner in 
figure and motion. Sensible qualities, what are they but the 
powers of different bodies in relation to our perception, and 
do they not depend in themselves upon bulk, figure, the con- 
texture and motion of the parts ? which puts a kind of rela- 
tion between them. Thus our idea of power may very well be 
placed in my opinion among the other simple ideas. 

Th. [At bottom the ideas which we have just enumerated 
are composite ; those of sensible qualities hold their place 
among the simple ideas only because of our ignorance, and the 
others which we know distinctly, keep their place only by an 
indulgence which it were better they should not have. It is 
almost the same with regard to the common axioms, which 
might be and which deservedly should be proved among the 
theorems, and which are allowed to pass nevertheless as 
axioms, as if they were primitive truths. This indulgence 
does moi'e harm than we think. It is true we are not always 
in a position to do without it.] 

§ 4. Ph. If we consider the matter carefully, bodies do not 
furnish us by means of the senses Avith so clear and so distinct 
an idea of active power as that which we have from reflection 
upon the workings of our mind. There are, I believe, but two 
kinds of actions of which we have an idea, viz. : thinking and 
motion. Of thought, body gives us no idea, and it is only 
through reflection that we have it. Neither have we from the 
body any idea of the beginning of motion. 

Th. [These considerations are most excellent, and although 
here I take thought in a manner so general that it includes all 
perception, I do not wish to dispute the use of terms.] 

Ph. When the body is itself in motion, this motion in the 
body is an action rather than a passion ; but when a billiard- 
ball yields at the stroke of the cue, it is not an action of the 
ball, but a simple passion. 



170 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



Th. [There is something to be said upou that point, for the 
bodies did not receive motion in the impact, according to the 
hxws observed therein, if' they already had not motion in 
themselves. But pass we now this point.] 

Ph. The same is true when it pushes another ball which it 
tinds in its way and puts in motion ; it only communicates to 
it the motion it had received, and itself loses just as much. 

Th. [I see that this erroneous view, which the Cartesians 
have brought into fashion, as if bodies lost as much motion as 
they give to others, which is to-day overthrown by experi- 
ments and by reason, and abandoned moreover by the illustri- 
ous author of " The Search after Truth," ^ who has published 
a brief treatise for the express purpose of retracting it, still 
gives scholars occasion to be mistaken in constructing trains 
of reasoning upon so ruinous a foundation.] 

Ph. The transfer of motion gives us only a very obscure 
idea of an active power of motion in the body so long as we 
see nothing else than that the body transfers motion but does 
not in any way produce it. 

Th. [I do not know whether they here maintain that motion 
passes from subject to subject, and that the same motion (?V?em 
numero) is transferred. I knoAV that some, contrary to the 
view of the entire scholastic philosophy, have gone that far, 
among others the Jesuit, Father Casati. But I doubt whether 
this is your view or that of your scholarly friends, ordinarily far 
removed from such fancies. If, however, the same motion is 
not transferred, we must admit that a new motion is produced 
in the body which receives it : thus the one which gives 
would really act, although it would be passive at the same 
time while losing its force. For although it is not true that 
the body loses as much motion as it gives, it is always true 
that it loses some motion and that it loses as much force as it 
gives, as I have elsewhere explained, so that it is always nec- 
essary to admit in it force or active power. I understand 
power in the more noble sense which I have explained a little 
before, in which tendency is united with faculty. Nevertheless, 

1 Malebranclie, De la Recherche de la Verite, Hui. The "brief treatise" 
referred to is entitled: Traite de la communication du mot^ement, and may 
be found in Vol. 3 of the German translation of Malebranclie's works, Halle, 
1777-80. — Tr. 



cii XXI] ON HUMAN UNDERSTANDING 177 

I am always agreed with you, that the clearest idea of 
active power comes to us from the mind. It is also only / 
in things which are analogous to the mind, that is to say, in 
entelechies, for matter properly speaking shows only passive 
power.] 

§ 5. Ph. We find in ourselves the power to begin or not to 
begin, to continue or to end many actions of our soul and 
many motions of our body, and this simply by a thought or 
choice of our mind, which determines and commands, so to 
speak, that such a particular action be done or not done. This 
power we call Will. The actual use of this power is called 
Volition ; the cessation or production of the action which fol- 
lows such a command of the soul, is called voluntary, and all 
action done without such direction of the soul is called invol- 
untary. 

Th. [I find all that very good and just. However, to speak 
more fairly, and to go perhaps a little farther, I will say that 
volition is the effort or tendency (conatus) towards what is 
considered good and against that considered bad, so that this 
tendency results immediate^ from the consciousness one has 
of them. And the corollary of this definition is this cele- 
brated axiom : that will and power united, action follows, 
since from all tendency action follows when it is not hin- 
dered. Thus not only the internal voluntary actions of our 
minds follow from this conatus, but also the external, that is to 
say, the voluntary movements of our bodies, in virtue of the 
union of the soul and the body, the reason of which I have 
elsewhere given. There are besides the efforts resulting from 
the insensible perceptions, of which we are not conscious, . 
which I prefer to call appetitions rather than volitions (al- ■ 
though there are also apperceptible appetitions), for those 
actions alone are called voluntary of which we may be con- 
scious, and upon which our reflection may fall when they fol- 
low the consideration of good and evil.] 

Ph. The power of perceiving we call understanding : it in- 
cludes the perception of ideas, the perception of the signifi-i 
cation of signs, and, finally, the perception of the agreement 
or disagreement existing between any of our ideas. 

Th. [We perceive many things within and without us, H 
which we do not understand, and we understand them, when 

N 



178 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

wo have distinct ideas of them, together with the power of 
reflection and of drawing from them necessary truths. Ani- 
mals therefore have no understanding, at least in this sense, 
although they have the faculty of perceivijig impressions 
more remarkable and more distinct, as theiisoar perceives a 
person who shouts at him, and goes straight for this person, of 
whom he had had before only a cloudy perception, but con- 
fused as of all other objects which fell under his eyes, and 
whose rays struck his crystalline humor. Thus in my view 
the understanding corresponds to what among the Latins is 
called intelledus, and the exercise of this faculty is called 
intellection, which is a distinct perception united with the fac- 
ulty of reflection, which is not in animals. Every perception 
united with this faculty is a thought, which I do not accord to 
the animals any more than understanding, so that we may say 
there is intellection when thought is distinct. For the rest, 
the perception of the signification of signs does not deserve 
to be distinguished here from the perception of the ideas 
signified.] 

§ 6. Fh. It is commonly said that the understanding and 
the will are two faculties of the soul, a term suitable enough if 
used as we ought to use all words, taking care that they cause 
no confusion to spring up in the thoughts of men, as I suspect 
has happened here in the case of the soul. And when we are told 
that the will is that superior faculty of the soul which rules 
and orders all things, that it is or is not free, that it deter- 
mines the lower faculties, that it follows the dictamen of the 
understanding ; although these expressions may be understood 
in a sense clear and distinct, I fear, however, that they have 
caused to arise in many persons the confused idea of so many 
distinct agents acting distinctly in us. 

Th. The question has exercised the scholastics a long time 
whether there is a real distinction between the soul and its 
faculties, and whether one faculty is really distinct from 
another. The Realists have said yes, and the Xominalists, 
no, and the same question has been agitated as to the reality 
of many other abstract entities, which should meet the same 
fate. But I do not think we need here decide this question 
and plunge into these difficulties, although I remember that 



CH. XXI] ON HUMAN UNDERSTANDING 179 

Episcopius ^ found it of such importance that he thought he 
coukl not maintain the freedom of man if the faculties of the 
soul were real entities. However, if they were real and dis- 
tinct entities, they can pass for real agents only in extravagant i 
speech. It is not the faculties or qualities which act, but sub- ) 
stances by means of the faculties. / 

§ 8. Ph. So long as man has the power to think or to 
refrain from thinking, to move or not to move according to 
the preference or choice of his own mind, so long he is free. 

Th. [The term freedom is very ambiguous. There is free- 
dom of right and of fact. As regards that of right a slave is 
not at all free, a subject is not wholly free, but a poor man is 
as free as a rich man. Freedom of fact consists either in the 
power to loill as one ought, or in the power to do what one wills. 
It is of the freedom to do of which you speak, and it has its 
degrees and varieties. Generally he who has the most means 
is the freest to do what he wills : but in 2^cirticular freedom is 
understood of the use of things which are ordinarily in our io^ 
power, and above all, of the free use of our body. Thus the ^ (p'' 
prison and the diseases which prevent us from giving to our 
body and our limbs the motion we wish and which we can 
ordinarily give them detract from our freedom : thus a prisoner 
is not at all free, and a paralytic has no free use of his limbs. 
Freedom of ivill is furthermore understood in two different 
senses. The first is when it is opposed to the imperfection or 
the slavery of the spirit, which is a coaction or constraint, but 
internal like that arising from the passions. The other sense 
has place when freedom is opposed to necessity. In the first 
sense the Stoics said that the wise man alone is free ; and in 
fact the spirit is not at all free when it is filled with a great 
passion, for one cannot then will as he should, that is to say, 
with the deliberation which is requisite. Thus God alone is 
perfectly free, and created spirits are so, only to the extent 
that they are superior to their passions. And this freedom 
concerns properly our understanding. But the freedom of 
spirit, opposed to necessity, concerns the naked will, and in so 
far as it is distinguished from the understanding. This is 

1 Simon Episcopius, 1583-1G43. The piece referred to is the De libero arhi- 
trio, particiilarly the second chapter; it is found in his Opera Theologica, Yo\. 
1, p. 198, Div. II., 2d ed. London and Rotterdam, 1GG5-1(378, 2 vols., foh — Tk. 



ISO 



LKIUNI'IZ'S CUITIQUE OF LOCKE [inc. ii 



what is called free-ioill (franc-arbilre) and it consists in this, 
that wo will tiiat the strongest reasons or impressions which 
the understanding presents to the will do not prevent the act 
of the will from being contingent, and do not give it an abso- 
lute, and, so to speak, metaphysical necessity. And it is in 
this sense that I am accustomed to say that the understanding 
can determine the will, according to the prevalence of percep- 
tions and reasons, in a manner which, even where it is certain 
and infallible, inclines without compelling.^ 

§ 9. Ph. It is well also to consider that no one has yet 
thought of taking as a/ree agent a ball, whether in motion by 
the stroke of a racket or at rest. This is because we do not 
conceive of a ball as thinking or as having any volition, which 
makes it prefer motion to rest. 

Th. [If that were free which acts without hindrance, a ball 
once in motion in a level horizon would be a free agent. But 
Aristotle has already well remarked that to call acts free, Ave 
demand not only that they be spontaneous, but further that 
they be deUherate.^~\ 

Ph. This is why we consider the motion or rest of balls 
under the idea of a necessary thing. 

Til. [The appellation necessary requires as much circumspec- 
tion as that oi free. This conditional truth, viz.: siLpposing the 
ball to be in motion in a level horizon ivithout hindrance, it ivill 
continue the same motion, may pass as in some sort necessar}', 
although at bottom this consequence is not entirely geometri- 
cal, being only presumptive, so to speak, and based upon the 
wisdom of God who changes not his influence without a 
reason, which it is presumed is not at present to be found. 
But this absolute proposition : the ball here is noiv in motion in 
this p?a»e, is only a contingent truth, and in this sense the ball 
is a contingent, not a free, agent.^ 

§ 10. Ph. Suppose that a man, while in a profound sleep, is 
carried into a room, wdiere is a person, whom he much longs to 

1 Cf. Essais de TModic^e, Pt. I., §§ 51, 52, Gerhardt, 6, 1.30-131 ; Erdmann, 
517; also Eduard Dillmann, Eine neue Larstellung der Leibnizischen Monad- 
enlehre auf Grund der Quellen, pp. 41() sq. ; Leipzig: 0. R. Reisland, 1891.— 
Tr. 

2 Cf. Eth. Nic, IIL, 4, ad fin., 5; 1111 sq.; translation by F. H. Peters, 
M.A., London: C. Kegan Paul & Co., 1881. — Tr. 



cir. xxi] ON HUMAN UNDERSTANDING 181 

see and to meet, and that the door is locked upon him ; this 
man wakes up and is delighted to find himself with this per- 
son, and lives thus in the room with pleasure. I think no one 
presumes to doubt that he remains voluntarily in that place. 
Yet he is not at liberty to go out if he wishes. Thus freedom 
is not an idea belonging to volition. 

Th. [I find this example very well chosen to show that in a 
sense, an act or a state may be voluntary without being free. 
Still when philosophers and theologians dispute upon/?-ee loill, 
they have altogether another sense in view.] 

§ 11. Ph. Ereedom is wanting when paralysis prevents the 
limbs from obeying the determination of the mind, although, 
in the case of the paralytic even, to remain sitting still might 
be voluntary so long as lie prefers sitting still to changing 
his place. Voluntary is not then opposed to necessary, but to 
involuntary. 

Til. [This precision of expression would be agreeable enough 
to me, but usage is far from it ; and those who oppose freedom 
to necessity, mean to speak not of external acts, but of the act 
itself of willing.] 

§ 12. Ph. A man awake is no more at liberty to think or 
not to think, than he is at liberty to prevent or not to prevent 
his body from touching any other body. But to transfer his 
thoughts from one idea to another is often within his deter- 
mination. And in that case he is as much at liberty as regards 
his ideas, as he is as regards the bodies upon which he rests, 
being able to transfer himself from one to the other as the 
fancy arises. There are, however, ideas, which, like certain 
(bodily) movements, are so fixed in the mind, that, in certain 
circumstances, you cannot avoid them whatever effort you 
make. A man upon the rack is not at liberty to put aside the 
idea of pain, and sometimes a violent passion acts upon our 
mind as the most violent wind acts upon our body. 

Til. [There is order and connection in ideas, as there is in 
(bodily) movements, for the one corresponds perfectly to the 
other, although the determination in the movements be uncon- 
scious and free, or with choice in the thinking being whom good 
and evil only cause to incline withoiit forcing him. For the soul, 
Avhile representing bodies, preserves its (own) perfections, and 
although dependent upon the body (in seizing the good) in the 



lt,2 LElliNliZ'S CKiriQUE OF LOCKE [bk. 



vDluiitary acts, it is independent and makes the body depend 
upDn itself in others. lUit this dependence is only metaphysical, 
anil consists in the considerations which God has for the one 
while ruling the other, or rather for both, according to the 
original perfections of each ; whilst physical dependence would 
consist in an immediate influence, which the one would receive 
from the other on which it depends. For the rest, there come 
to us involuntary thoughts, partly from outside by means of 
objects which strike our senses, and partly from within by 
reason of the impressions (often insensible) which remain 
from preceding perceptions whose action continues and which 
mingle with those which appear for the first time. As regards 
these we are passive, and even when we wake up, images 
(under which designation I include not only the representa- 
tions of figures, but also those of sounds and other sensible 
qualities) come to us, as in dreams, without being called. 
The German language calls them. Jliegende Gedaiiken, that is, 
flying thoughts {pensees volantes), which are not within our 
control, and among which there are sometimes many absurdi- 
ties which raise scruples in good people, and furnish exercise 
to casuists and directors of consciences. It is as in the magic 
lantern, which makes figures appear upon the wall according 
as something within is turned. But our mind, perceiving 
some image which recurs to it, may say ; stop there, and, so to 
speak, arrest it. Moreover, the mind enters, as seems good 
to itself, into certain trains of thought, Avhich lead it on to 
others. But this is true only when internal or external impres- 
sions do not at all prevail. It is true that in this thing men 
differ very much, both according to their temperament and 
according as they have exercised their control, so that one can 
master impressions where another lets them go. 

§ 13. Ph. Necessity takes place wherever thought is wholly 
wanting. And this necessity, when found, is an agent capable 
of volition, and when the commencement or continuation of 
any action is contrary to the preference of his mind, I call it 
compulsion; when the hindering or stopping of an action is 
contrary to his volition, I may call it restraint. Agents which 
have absolutely neither thought nor volition are in all respects 
necessary agents. 

Th. [It seems to me that, properly speaking, although 



cii. xxi] ON HUMAN UNDERSTANDING 183 

volitions are contingent, necessity should not be opposed to 
volition, but to contingency, as I have already remarked in § 9, 
and that necessity should not be confounded with determina- 
tion, for there is no less connection or determination in thoughts 
than in movements (to be determined being a wholly different 
thing from being pushed or forced by compulsion). And if 
we do not always notice the reason which determines us or 
by which we determine ourselves, it is because we are as 
little capable ourselves of perceiving the entire play of our 
mind and its thoughts, very often imperceptible and confused, 
as we are of recognizing all the machinery which nature causes 
to play in the body. Thus, if by necessity, you mean the cer- 
tain determination of man, which a perfect knowledge of all 
the circumstances within and without could make a perfect 
mind foresee, it is certain that thoughts being as determined 
as the motions they represent, every free act would be a neces- 
sary act. But necessity must be distinguished from contingency » . 
although determined ; and not only are contingent truths not < 
at all necessary, but fiirther, their connections are not always , 
of an absolutely necessary character ; for it must be admitted 
that there is some difference in the manner of determining ' 
between consequences which take place in necessary matter 
and those which take place in contingent matter. Geometrical . 
and metaphysical consequences necessitate, but physical and . 
moral incline without necessitating; the physical even having 
something of the moral and voluntary as related to God, since 
the laws of movement have no other necessity than that of (the ; 
principle, or choice, of — Tr.) the best. Now God chooses freely 
although he is determined to choose the best; and as bodies 
themselves do not choose (God having chosen for them), usage 
has decided that they be called necessary agents, to which I am' 
not opposed, provided we do not confound the necessary and 
the determined, and do not suppose that free beings act in 
an indeterminate manner, an error which has prevailed in cer- 
tain minds and which destroys the most important truths, even 
this fundamental axiom: that nothing happens without reason, .'. 
without which neither the existence of God nor other great • 
truths could be satisfactorily demonstrated. As for compulsion 
it is well to distinguish two kinds, the one physical, as when 
a man is carried in spite of himself into prison, or thrown 



Ksj LLLBNITZ'S CIUTIQUE OF LOCKE [uk. ii 

ilown a precipice ; the other moral, as, for example, the con- 
straint of a greater evil, and this act,^ although in a sense 
forced, does not cease to be voluntary.^ One may be compelled 
also, by the consideration of a greater good, as when a man is 
tempted by proposing to him a too great advantage, although it 
is not customary to call this constraint.] 

§ 14. Ph. Let us see now if we cannot put an end to that 
long agitated, and in my opinion very unreasonable, because 
unintelligible, question: WJiether man's icill is free or no. 

Th. [There is much reason for the exclamation with respect 
to the strange manner of men who torment themselves by agi- 
tating badly conceived questions : They seek for lohat they knoiv, 
and knoiv not for v:hat they seek.~\ 

Ph. Freedom, which is only a pov.'er, belongs only to agents 
and cannot be an attribute or modification of the will, which is 
itself nothing else than a power. 

Th. [You are right, sir, according to the proper use of 
words. One can, however, in some measure excuse received 
usage. Thus it is customary to attribute power to heat or to 
other qualities, i.e. to the body in so far as possessed of that 
quality : and in like manner the intent here is to ask if man is 
free in willing.] 

§ 15. Ph. Freedom is the power a man has of doing or not 
doing any act conformably to his will. 

TJi. If men understood onh' that by freedom, when they ask 
whether the will, or the arbiter is free, their question would be 
truly absurd. But you will see presently what they ask, and 
indeed I have already touched upon it. It is true but by 
another principle, that they (at least many) do not cease to 
ask for the absurd and the impossible, in desiring a freedom 
of equilibrium absolutely imaginary and impracticable, and 
which indeed would not serve them, were it possible for them 
to have it, i.e. to have the freedom of willing against all the 
impressions which can come from the understanding, which 
would destroy true freedom together with the reason, and lower 
us below the beasts. 

1 Gerhardt reads: "et cette action, qiioyque forcee en quelque fa^on"; 
Erdmann and Jacques: " ear raction, qu'elle fait faire," i.e. for the act which 
it makes you do. — Tr. 

2 Cy. Kant, Kritik d. jrrakt. Vernunft, Th. I., Bd. I., Hpst. 1, § 6, Anm.; 
translation by T. K. Abbott, 4th ed., revised and enlarged. London : Lonsrmans, 
1889. — Te. 



cii. xxi] ON HUMAN UNDEESTANDING 185 

§ 17. Ph. He who should say that the power of speaking 
directs the power of singing, and that the power of singing^ 
obeys or disobeys the power of s})eaking, would express him- 
self in as proper and intelligent a manner, as he who says, as 
has been usual, that the will directs the understanding, and 
that the understanding obeys or disobeys the will. § 18. 
Nevertheless this manner of speaking has prevailed, and has 
caused, if I am not mistaken, much confusion, although the 
power of thinking operates no more upon the power of choos- 
ing and the contrary, than the power of singing upon that of 
dancing. § 19. I grant that this or that thought may furnish 
man the occasion of exercising his power of choosing and that 
the mind's choice may be the cause of its actually thinking on 
this or that thing, just as actually singing a certain tune may 
be the occasion of dancing such a dance. 

Th. [There is a little more than the furnishing of occasions, 
since there is some dependence ; for you can will only what 
you find to be good, and according as the faculty of under- 
standing is improved the choice of the will is better, as on the 
other hand, according as man has vigor of ivill he determines 
his thoughts according to his choice, instead of being deter- 
mined and carried away by involuntary perceptions.] 

Ph. Powers are relations, not agents. 

Th. [If the essential faculties are only relations and add 
nothing whatever to the essence, the qualities and t!ie faculties 
that are accidental or subject to change are something else, and 
we may say of these last that the one often depends upon the 
other in the exercise of their functions.] 

§ 21. Ph. In my opinion the question should not be, whether 
the will is free, — that is to speak in a very improper manner, 
— but whether the man is free. That granted, I say that so 
lung as any one can by the direction or choice of his mind 
])refer the existence of an action to its non-existence, and the 
contrary, i.e. can make it exist or not exist according as he 
wills, so long he is free. And we can scarcely say how we 
could possibly conceive a being freer than so far as he is able 
to do what he wills. So that man seems to be as free in refer- 

1 Geiiianlt reads: "parler," a MS. or typographical error; cf. Locke, 
Fhilos. Wiirks (Bolm's e<l.), Vol. 1, p. 370. Erdinann and Jacques read: 
"chanter," which the translation follows. — Tr. 



ISr, LKUiMTZ'S ClUTKiUE OF LOCKE [bk. ii 



pncp to those actions which depend upon this power he finds 
in liiniself, as it is possible for freedom to make him, if I may 
so express myself. 

Th. [When Ave reason about the freedom of the Avill or upon 
five-will {franc arbitre), we do not ask if man can do what 
he wills, but if tliere is enough independence in his will itself. 
We do not ask if he has free limbs or elbow-room, but if he 
has a free spirit, and in what it consists. In this respect one 
intelligence might be freer than another, and the supreme 
intelligence will exist in perfect freedom of Avhich creatures 
are not at all capable.] 

§ 22. Ph. Men naturally inquisitive, and who love to remove 
as much as they can from their minds the thought of guilt, 
although it be by reducing themselves to a state worse than 
that of a fatal necessity, are not, however, satisfied with this. 
Unless freedom extends still farther, it is not to their taste, 
and in their opinion it is a very good proof that man is not at 
all wholly free, unless he has as well the freedom to will as that 
of doing what he wills. § 23. Concerning which I believe 
that man cannot be free in reference to this particular act of 
willing an action which is in his power, when this action has 
been once proposed to his mind. The reason therein is wholly 
manifest, for the action depending upon his will, must una- 
voidably exist or not exist, and its existence or non-exist- 
ence following without fail exactly the determination and 
choice of his Avill, he cannot avoid willing the existence or 
non-existence of this action. • 

Til. [I should think he could suspend his choice, and that 
this happens very often ; above all, when other thoughts inter- 
rupt deliberation : thus, although the action deliberated upon 
necessarily exists or not, it does not at all follow that you 
must necessarily determine upon its existence or non-existence ; 
for non-existence may happen again for want of resolution. 
Thus the Areopagites actually released the man whose case 
they had found too difficult to decide, deferring it to a term 
far distant, and taking a hundred years to consider it.] 

Ph. In making man free in this fasiiion, I mean in making 
the act of Avilling depend upon his will, another will or ante- 
rior faculty of volition is necessary in order to determine the 
acts of this will, and another to determine that, and thus to 



CH. XXI] ON HUMAN UNDERSTANDING 187 

infinity ; for wherever you stop, the actions of the last will 
could not be free. 

Th. [It is true yoii speak incorrectly when yon speak as if 
■\ve willed to will. We do not will to will, but we will to do, 
and if we willed to Avill, we should will to will to Avill, and 
this would go on to infinity : meanwhile it is not necessary to 
conceal that by some voluntary acts we contribute often indi- 
rectly to other voluntary acts, and although one cannot will 
what he will, as he cannot even judge what he will,^ he can, 
however, so act in advance that he judges or wills at the time 
what he would wish to be able to will or judge to-day. Men 
attach themselves to persons, lectures, and considerations favor- 
able to a certain party, they give no attention to that which 
comes from the opposite party, and by these addresses and a 
thousand others which they employ, most frequently without 
definite design and without thought, they succeed in deceiving 
themselves or at least in changing and converting or per- 
verting themselves according to what they meet.] 

§ 25. Ph. Since then it is evident that man is not at lib- 
erty to ^i:ill to tvill or not, the next thing demanded is, whether 
man is at liberty to ivill which of the two he pleases, for example, 
motion or rest? But this question is in itself so visibly absurd 
that it may suffice to convince any one who will reflect that 
freedom in no case concerns the will. For to ask whether a man 
is free to will what he pleases, motion or rest, speech or silence, 
is to ask whether a man can will what he wills, or be pleased 
with that with which he is pleased, a question which, in my 
opinion, needs no answer. 

Th. [It is true, nevertheless, that men find here a difficulty 
Avhich deserves to be removed. They say that after having 
known and considered all, it is still within their power to will 
not only what pleases them the most, but furthermore wholly 
the contrary, merely to show their freedom. But you must 
consider that this caprice or obstinacy, or at least this reason 
which hinders them from following other reasons, also enters 
into the balance and makes that please them which would 
otherwise not do so, so that choice is always determined by 
perception. They do not then will what they would, but what 

1 The French is: " et quoyqu' on ne puisse point vouloir ce qu' on veut, 
comme on ne pent pas menie jnger ce qu' on veut." — Til. 



188 LEIBNITZ'S CU ITIQUE OF LOCKE [bk. n 

pleases, although the will can contribute indirectly and as it 
were from afar to make anything pleasurable or otherwise, as 
I have already remarked. And as men scarcely recognize all 
these separate considerations, it is not astonishing that the 
mind is so perplexed in regard to this matter which has so 
many concealed windings.] 

§ L'O. Ph. When men ask what it is that determines the 
will, the true reply is, the mind. If this answer is not satis- 
factory, it is plain that the meaning of the question reduces to 
tliis: Wliat moves the mind on eMcli 2Kirticular occasion to deter- 
mine to such jjarticidar motion or rest its genercd x>ower of direct- 
ing its facidties totvards motion or rest? To this I reply that 
what leads us to remain in the same state or continue the 
same action, is solely the present satisfaction we find therein. 
On the other hand, the motive which incites to change is 
always some uneasiness. 

Th. [This uneasiness, as I have shown (in the preceding 
chapter), is not always a displeasure, as ease when found is 
not always a satisfaction or pleasure. It is often an insensible 
perception, which cannot be distinguished or recognized, which 
makes us lean to one side rather than the other, without our 
being able to give a reason for so doing.] 

§ 30. Ph. Will and desire should not be confounded : a man 
desires to be freed from the gout, but understanding that the 
removal of this pain may cause the transfer of a dangerous 
humor into some more vital part, his will cannot be determined 
to any action, which may serve to remove this pain. 

Th. [This desire is a kind of an inclination of will {velleitey 
as compared with a complete volition. We should will, for 
example, if there were no greater evil to be feared, if we 
obtained what we wish, or if perhaps there were a greater 
good to be hoped for if we went forward. But we can say 
that man wills to be delivered from the gout with a certain 
degree of volition, but which does not always go on to the last 
effort. This volition is called Velleity when it includes some 
imperfection or impotency.] 

§ 31. Ph. It is well to consider, however, that what deter- 
mines the will to act is not the greater good, as is ordinarily 
supposed, but rather some actual uneasiness, and ordinarily 
1 Cf. New Essays, Book. II., chap. 20, § 6, Ph. and note, ante, p. 168. — Tr. 



CH. xxi] ON HUMAN UNPERSTANDING 189 

that which is most pressing. We may give it the name of 
desire, which is really an uneasiness of mind, caused by the 
want of some absent good, over and above the desire of being 
freed from pain. All absent good does not produce a pain 
proportionate to the degree of excellence which it has or which 
we acknowledge it to have; whilst all pain causes a desire 
equal to itself; because the absence of good is not always an 
evil, as is the presence of pain. Therefore we can look upon 
and consider an absent good without pain. But in proportion 
as there is anywhere desire, so is there uneasiness. § 32. Who 
is there who has not felt in desire what the wise man says 
of hope, "that being deferred it makes the heart sick" 
(Prov. 13: 12) ? Eachel cries "Give me children, or I die " 
(Gen. 30:1). § 34. When man is perfectly content with 
the state he is in, or when he is absolutely free from all 
uneasiness, what will can remain to him but to continue 
in that state ? Thus the wise Author of our being has 
put in men the inconvenience of hunger and thirst and other 
natural desires, in order to arouse and determine their wills to 
the proper conservation and continuation of their species. 
" It is better to marry than to burn," says St. Paul (1 Cor. 7:9). 
So true it is that the present sensation of a little burning has 
more power over us than the attractions of greater pleasures 
looked at in the distance. § 35. It is true that this maxim, 
it is the good and the greatest good which determines the 
will, is so firmly established that I am not at all surprised at 
having formerly regarded it as beyond doubt. But after strict 
inquiry I am forced to conclude that the good and the greatest 
good, although judged and acknowledged such, does not deter- 
mine the will ; unless coming to desire it in a manner propor- 
tional to its excellence this desire makes us uneasy at our 
deprivation of it. Suppose a man convinced of the utility of 
virtue so far as to see that it is necessary to the man who pro- 
poses anything great in this world, or hopes to be happy in 
the other : but until this man hungers and thirsts after right- 
eousness, his will will never be determined to any action in 
search for this excellent good, and any other uneasiness com- 
ing in the way will drag his will to other things. On the 
other hand, suppose a man given to wine considers that by 
leading the life he leads he is ruining his health and Avasting his 



190 LEIBMTZ'S CRITIQUE OF LOCKE [i3k. ii 

jiropiM-tv, that he is coming to be dishonored in the world, to 
hrini,' upon himself disease and to fall at last into poverty 
until ho no longer has wherewith to satisfy this passion for 
drink which so strongly possesses him : nevertheless, the 
returns of uneasiness which he feels in being absent from his 
companions in debauch, drag him to the tavern at the hours he 
has been wont to go there, though at the time he has before 
his eyes the loss of his health and estate, and perhaps even 
that of the happiness of the other life, happiness which he 
cannot regard as a good inconsiderable in itself, since he 
admits that it is much more excellent than the pleasure of 
drinking or the vain chatter of a company of debauchees. It is 
not then for want of casting the eyes upon the sovereign good 
that he persists in this intemperance ; for he sees it and 
acknowledges its excellence, to the extent that during the 
time that intervenes between his drinking hours, he resolves 
to apply himself to the search for this sovereign good ; but 
when the uneasiness of being deprived of his accustomed 
pleasure comes to torment him, this good which he acknowl- 
edges more excellent than that of drinking, has no longer 
power over his mind, and it is this actual uneasiness which 
determines his will to the action to which it is accustomed, 
and which thereby making very strong impressions prevails 
again at the first occasion, although at the same time he binds 
himself, so to speak, by secret promises no longer to do the 
same thing, and imagines that this "will be the last time that 
he will act against his highest interest. Thus he finds himself 
from time to time reduced to saying : 

Video meliora proboque, 
Deteriora sequor.^ 

I see the better way, I approve it, and I take the worse. 
This sentence which we acknowledge as true, and which is 
only too well confirmed by a constant experience, is easy to 
understand in this way, and there is perhaps no other sense in 
which it can be taken. 

T1i. [There is something beautiful and solid in these consid- 
erations. But I would not have you believe on that account 
tliat we must abandon those ancient axioms that the will 

1 Ovid, Metu)nor2>/i. T.lil.— Tk. 



CH, XX i] ON HUMAN UNDERSTANDING 191 

follows the greatest good, or that it flies from the greatest evil 
that it perceives. The source of the little application to true 
goods arises mainly from the fact that in matters and on the 
occasions where the senses act but little, the greater part of our 
thoughts are, so to speak, surd^ (I call them cogitationes coecm 
in Latin) i.e. void of perception and feeling, and consisting 
in the wholly empty employment of characters, as happens in 
the case of those who make algebraic calculations without con- 
sidering from time to time that the geometrical figures in 
question and the words ordinarily produce the same effect in 
this regard as the characters of arithmetic or algebra. One 
often reasons in words without having quite the same object 
in mind. Now this knowledge cannot move ; something living 
is necessary in order to arouse us. But thus it is that men 
most frequently think of God, of virtue, of happiness ; they 
speak and reason without definite ideas. Not that they can- 
not have them, since they are in their mind. But they do not 
trouble themselves to press their analysis. Sometimes they 
have ideas of an absent good or evil, but very feeble. It is 
then no wonder that they are scarcely affected. Thus if we 
prefer the bad it is because we perceive the good which it 
includes without perceiving either the bad therein or the good 
in the contrary consideration. We assume and believe, or 
rather we make the statement merely upon another's belief, or 
at most upon belief in the memory of our past reasonings, that 
the greatest good is on the better side, or the greatest evil on 
the other. But when we do not look at these at all, our 
thoughts and reasonings contrary to the feeling are a kind of 
jysittacism ^ which furnishes nothing at present to the mind ; 
and if we take no measures to remedy it, it is idle talk, as I 
have already remarked above (Bk. I., chap. 2, § 11), and the 
most beautiful precepts of morality together with the best 
rules of prudence take effect only in a soul which is sensible 
(either directly, or, because that cannot always be, at least in- 
directly, as I shall show presently) and which is no longer 
sensible to that which is contrary thereto. Cicero well says 

1 The French is : " sourdes." Cf. p. 193, near the end of Th. — Tr. 

2 Littre thus defines " psittacisnie," q^uoting this passage and tlie one further 
on, § r>7, Th., l)y way of illustration : " Etat d'esprit dans lequel on ne pense on 
n" parle qu'eu pcrroijuet," i.e. a state of the mind in which one thinks or 
speaks only as a parrot. — Tr. 



192 LEIBNITZ'S CHITKilE OF LOCKE [iik. n 



somewhere * that if our eyes could see the beauty of virtue, we 
■shouhl love it warmly; but that not being at all the case, nor 
anything C(iuivalent, we must not be astonished if in the strug- 
gle between the flesh and the spirit, the spirit so many times 
yields, since it does not clearly perceive its advantages. The 
struggle is nothing else than the opposition of different ten- 
dencies, which spring from confused and distinct thoughts. 
Confused thoughts often make themselves clearly felt, but 
our distinct thoughts are ordinarily clear only potentially; 
they might be clear, if we would apply ourselves to the 
penetration of the sense of the words or characters ; but not 
doing so, either through negligence, or because of the shortness 
of time, we oppose mere words, or at least, too feeble images 
to living feelings. I knew a man influential in church and 
state, whose infirmities made him resolve to diet ; but he ad- 
mitted that he had not been able to resist the odor of the 
viands, which, passing before his apartment, were carried to 
others. It is doubtless a disgraceful weakness, but it is just 
what men have done. But if the mind made good use of its 
advantages, it would triumph grandly. It would be necessary 
to begin with education, which should be so regulated as to 
render true good and true evil as sensible as possible, by in- 
vesting the notions which are formed of them with circum- 
stances more suited to this design ; and a full-grown man who 
lacks this excellent education should commence rather late, 
than never, to seek pleasures enlightened and reasonable, in 
order to oppose them to those of the senses, which are con- 
fused but impressive. And in fact, divine grace itself is a 
pleasure ^ which gives light. Thus when a man is in the midst 
of good impulses, he ought to make laws and regulations for 

1 Perhaps in De Fin., 2, 16, § 52: " Oculorum, inquit Plato, est in nobis 
sensus acerrimus, quibus sapientiam non ceruimus. Quani ilia ardentes amores 
excitaret sui, si videretur," where, however, the discourse is concerned with 
the particular virtue of wisdom, rather than with virtue in general. The pas- 
sage of Plato referred to is in the Phsedrus, 250 D. Cf. also, De Off., 2, 37: 
" Quis non admiretur spleudorem pulchritudinemque virtutis " ; and De Off., 
1,5: " Formam quidem ipsam, Marce fili, et tanquam faciem bonesti %ides; 
quae si oculis cerneretur, niirabiles amores excitaret sapientiae." — Tr. 

2 Cf. Spinoza, Ethica, Part V., Props., 32, 33, sq.; translation by R. H. M. 
Elwes, The Chief Works of Benedict de Spinoza, Vol. 2, pp. 263 sq. (Bohn's 
Philos. Library), London: George Bell & Sons, 188i. The best edition of 
Spinoza's AVorks is that of Van Vloten and Land, The Hague, 1882-1883. — Tr. 



CH. XXI] ON HUMAN UNDERSTANDING 193 

the future, and execute them rigorously, tearing himself away 
from those causes able to corrupt him, either brusquely or 
gradually, according to the nature of the circumstances, A 
journey expressly undertaken will cure a lover; a retreat will 
draAV us from the companions who support us in some bad in- 
clination. Francis of Borgia, General of the Jesuits, who has 
at last been canonized, being wont to drink largely when he 
was a man in high life, reduced himself little by little upon a 
small scale, when he thought of retiring (from the world) by 
causing a drop of wax to fall daily into the bottle which he 
was wont to emj^ty. To dangerous sensibilities we shall op- 
I'jose some other innocent sensibility, as agriculture, garden- 
ing; we shall shun idleness; we shall collect curiosities of 
nature and art ; we shall make experiments and researches ; 
we shall engage in some indispensable occupation, if we have 
none, or in conversation, or useful and agreeable reading. 
In a word, we must profit from good impulses as from the 
voice of God which summons us to make effective resolutions. 
And as we cannot always analyze the notions of true goods 
and true evils until we perceive the pleasure and pain they in- 
clude, we must once for all make this law in order to be moved 
by them : to attend to and follow henceforth the conclusions 
of reason once for all understood, although perceived after- 
ward and ordinarily only by thoughts surcV merely, and desti- 
tute of sense attractions ; and this in order to put yourselves 
finally in possession of control over the passions as well as of the 
insensible inclinations or uneasinesses, by acquiring this habit 
of acting according to reason, which makes virtue pleasant, 
and as it were natural. But it is not our business here to give 
and teach the precepts of morality, or the spiritual directions 
and address for the exercise of true piety ; it is enough that 
in considering the procedure of our soul, we see the source of 
our weaknesses, the knowledge of which gives, at the same 
time, that of their remedies.] 

§ 36. Ph. The present uneasiness which presses us, works 
only upon the will, and naturally determines it in view of that 
happiness to which we all aim in all our actions ; because every 
one regards pain and uneasiness (i.e. the restlessness, or rather 
inconvenience, which prevents us from being at our ease) as 

1 Cf. p. 191, near the beginning of Tli., and note. — Tr. 
O 



194 LKIiiMTZ'S CRITIQUE OF LOCKE [bk. ii 

incompatible with happiness. A little pain suffices to corrupt 
all the pleasures we enjoy. Consequently that which deter- 
mines incessantly the choice of our will to the succeeding 
action will always be the removing of pain, as long as we feel 
any touch of it; this removal being the first step towards 
happiness. 

Th. It' you take your uneasiness or inquietude as a veritable 
displeasure, in this sense I do not admit that it is the sole in- 
centive. Most frequently these are the little insensible per- 
ceptions which might be called imperceptible pains if the 
notion of 2>«''i did not include apperception. These little im- 
pulsions consist in delivering themselves continually from 
little obstacles towards which our nature works withoiit think- 
ing of them. This tineasiness consists in truth in this, that 
we feel without knowing it, which fact makes us act in passion 
as well as when we appear most tranquil; for we are never 
without some action and motion, which arises only from the 
fact that nature always labors to put herself more at her ease. 
And this it is which determines also before all consultation in 
the cases lohich appear to us the most indifferent, because we are 
never perfectly in suspense and we cannot be exactly equally 
divided between two cases. Now if these elements of pain 
(which degenerate into veritable pain or displeasure sometimes 
Avhen they overgrow) were true pains, w^e should always be 
miserable in pursuing the good that we seek with uneasiness 
and spirit. But it is wholly the contrary ; and as I have 
already said above (§ 6 of the preceding chapter), the mass 
of these continual little successes of nature, which puts it more 
and more at ease in reaching for the good and enjoying its 
image, or lessening the feeling of pain, is already a consider- 
able pleasure, and often worth more than the enjoyment even 
of the good; 2a\^ very far from being obliged to regard this un- 
easiness as incompatible loith hcqypiness, I find that uneasiness is 
essential to the happiness of created beings which never con- 
sists in complete possession,^ — this makes them insensible, and 

1 Cf. the famous passage of Lessing, 1729-1781, regarding the ' search after 
truth, rather than its possession,' in the Theoloc/. Streitsrhnften, Eine Duplik, 
1778, 1, ad Jin., Werke, Bd.lO, s. Ill, Stuttgart, 1809: " Xicht die Wahrheit, in 
deren Besitz irgend ein Mensch ist, oder zu sein vermeiut, sondern die auf- 
richtige Muhe, die er angewandt hat, hinter die Wahrheit zukommen, macht 
den Werth des Menscheu. Deun uicht durch den Besitz, sondern dureh die 



CH. XXI] ON HUMAN UNDERSTANDING 195 

as it were stupid, — but in a progress continuous and uninter- 
rupted towards the greatest good, which cannot fail to be ac- 
companied by a desire, or at least, a continual uneasiness, but 
Avhich, as I have just explained, does not go so far as to incon- 
venience, but limits itself to those elements or rudiments of 
pain, partly unconscious, which do not cease to be sufficient to 
serve as an incentive and to arouse the will ; as does appetite 
in a man who is well when it does not go to that inconvenience 
which makes us impatient and torments us by a too great at- 
tachment to the idea of what we lack. These appetitions, small 
or great, are what are called in the schools mohis primo lyrimi, 
and are truly the first steps which nature makes us take not 
so much towards happiness as towards joy, for they relate only 
to the present ; but experience and reason teach us to rule 
these appetitions and to control them so that they may con- 
duce to happiness. I have already spoken to this effect (Book 
I., chap. 2, § 3). The appetitions are like the natural ten- 
dency of the stone, which goes the most direct, but not always 
the best path towards the centre of the earth, not being able 
to see beforehand that it will meet rocks upon which it will 
break in pieces, whilst it would approach its end more directly 
if it had mind and the means of turning aside from them. 
Thus it is that going straight towards present pleasure we 
sometimes fall over the precipice of misery. Hence, reason 
opposes thereto images of the greatest good or evil to come, 
and a firm resolution and habit of thinking before acting, and 
then of following what shall have been recognized as the best, 

Nachforschunjj der Wahrheit erweitern sich seine Kriifte, woriii allein seine 
immer wachsende Volllvommenheit besteht. Der Besitz maclit ruhiij, trage, 
stolz . . ." ; i.e. " Not the truth, in possession of which at any time a man is, 
or thinks he is, hut the genuine effort he lias made to discover the trutli, con- 
stitutes the woi'th of the man. For not tlirougli possession, hut through the 
search after the trutli, are his powers expanded, wherein alone consists his ever 
growing perfection. Possession makes (him) qniet, lazy, proud . . ." 

The real significance of this famous passage in relation to the problem of 
knowledge is not that knowledge is impossible, i.e. Agnosticism, for this is 
strictly the meaning of the term ; but ratlier that the attainment of truth is 
possible, and that the human mind, having in its very constitution infinite 
elements and a capacity for an infinite ideal, can never rest satisfied with any 
present attainment or form of expression as final, but must continue to strive 
after the perfect truth as embodied in the infinite. Cf. an article by the 
translator, entitled " Revelation, Inspiration, and Authority," in " The Andover 
Review," April, 1891. — Tr. 



lOG LEIBNITZ'S CRITIQUE OF LOCKE [bk. n 



even when the sensible reasons of our conclusions are no longer 
present in the mind, and consist of scarcely more than feeble 
impressions or even of sunl thoughts, which give Avords or 
signs destitute of an actual explanation, so that all consists in 
tlie: Consider it well, and in the: Be mindful; the first in 
order to the making of laws, the second for their following, 
even when you do not think of the reason which has called 
tlieni into existence. It is, however, Avell to think of them as 
much as possible, in order that the soul may be filled with a 
rational joy and a pleasure accompanied with light.] 

§ 37. Fh. These precautions are doubtless so much the 
more necessary as the idea of an absent good can counter- 
balance the feeling of some uneasiness or displeasure by which 
we are at present tormented, only so far as this good arouses 
any desire in us. How many men there are to whose minds 
the unspeakable joys of paradise are represented by lively 
pictures which they recognize as possible and probable, who 
nevertheless would willingly content themselves with the hap- 
piness which they enjoy in this world. It is the uneasiness of 
their present desire getting the better of them and bearing 
them rapidl}' towards the pleasures of this life which deter- 
mines their wills to seek them : and during all this time, they 
are wholly insensible to the goods of the other life. 

Th. [This arises in part from the fact that men very often 
are but little persuaded ; and, although ifiey say they are, a 
hidden unbelief reigns in the depths of their souls ; for they 
have never understood the excellent reasons which verify this 
immortality of souls, worthy of the justice of God, which is 
the foundation of true religion, or rather they no longer re- 
member that they understood them, one or the other of which 
conditions however is necessary in order to conviction. Few 
men indeed think that the future life, as true religion and 
indeed true reason teaches it, is possible, and they are still 
farther from thinking it probable, not to say certain. All that 
they do think about it is but a j)sittacism, or gross and vain 
images after the Mahometan fashion, in which they them- 
selves see little likelihood. For thej^ are very far from being 
moved by them, as (according to report) were the soldiers 
of the Prince of the Assassins, the Old Man of the Moun- 



cii. xxi] ON HUMAN UNDERSTANDING 197 

tain/ who were carried away Avhen fast asleep into a place full 
of delights, where, believing themselves in the paradise of Ma- 
homet, they were imbued by the angels or counterfeit saints with 
such opinions as this prince desired, and whence after having 
been stupefied anew they were carried to the place whence they 
had been taken; this emboldened them afterwards to undertake 
everything, even attempts u})on the lives of princes, enemies of 
their chief. I do not know whether this Lord^ or Old Man of the 
Mountain was injured ; for not a few great princes may be named 
whom he had caused to be assassinated, although you may see 
in the English historians the letter, attributed to him, exon- 
erating King llichard I. of the assassination of a Count or 
Prince of Palestine,^ whom this Old Man of the Mountain ad- 
mitted he had had killed because he had been insulted by him. 

1 Tlie usual translation of " Sheikh-al Jebal," the title of the supreme ruler 
of the Assassins, a secret society whose distinguishing feature was the employ- 
ment of secret assassination against all enemies; a practice introduced by 
Hassan Ben Sabbah, the first chief of the sect. Otherwise the principles of 
the society were the same as those of the Ismaelites, viz. 1. No fixed rules 
of religion or morality, all actions indifferent, internal disposition alone of 
value. 2. Belief that the Immams of Ismael's line were now invisible, hence 
implicit obedience on part of true believers due to their vicegerents on earth. 
3. Allegorical interpretation of the Koran, defending or rejecting any doctrine 
at pleasure, as occasion required. 

The society was made up of seven ranks or orders : 1. The Sheikh ; 2. the 
Daial-Kirbal, or grand-priors ; 3. the Dais, or priors ; 4. Refiks, associates 
not initiated, as were t^ former, into all the secret doctrines; 5. the Fedais, 
"devoted ones," a band of youths uniuitiated and blindly obedient to the 
chief; G. Lasiks, or novices; 7. common people, laborers, and mechanics. On 
these was enjoined the most rigid observance of the Koran. The initiated 
regarded all positive religion and morality as worthless. The Fedais were the 
assassins proper. Whenever the chief wished for their service he had them 
intoxicated with hashish, or the hemp-plant, and transported into his splendid 
gardens, where they were surrounded with every sensual pleasure, and by this 
foretaste of Paradise which the chief alone could grant led to obey his shghtest 
command implicitly, even to the surrender of their own lives. From this cir- 
cumstance they were called Hashishin, or hemp-eaters. This word the Euro- 
peans changed into Assassins, and thus it was transplanted into the Western 
languages with the signification of murderers. See Von Hammer, Geschichte 
der Assassinen, 1818; Michaud, Histoire des Croisades, 2, pp. 465-484; 
F. Walpole, The Ansayrii, or Assassins, 3 vols., 1851 ; Gayard, Fragments 
relatifs a la Doctrine des Ismaelis, 1874; De Sacy, Memoires de V Institut, 4, 
1818, discusses the etymology fully. — Tr. 

2 Gerhardt reads : " Seigneur on Senior (Vieux) de la Montagne." — Tr. 

3 The Margrave Conrad of Montferrat, one of Saladiu's brave adversaries. 
Cf. Gibbon, Decline and Fall, Milman's ed., chap. 59, and note 74, also Milman's 
note ; Weil, Gesch. d. Chalifen, Vol. 3, p. 423; Wilken, Gesch. d. Kreuzzuge, 
Vol.4, p. 485S5. — Tr. 



U)S LEIBNITZ'8 CRITIQUE OF LOCKE [bk. ii 

Although that may be so, it was perhaps because of his great 
zeal for his religion that this Prince of the Assassins wished 
to give his people a favorable idea of paradise which should 
always 'accompany their thoughts of it and prevent them 
from being surd; without claiming on that account that they 
should believe that they had been in paradise itself. But 
supposing he had made this claim, it would not necessarily be 
astonishing if these pious frauds had been more efficacious than 
the truth badly managed. Yet nothing would be stronger than 
truth if we devoted ourselves to its complete knowledge and 
cultivation ; and we should have in it without doubt the means 
of strongly influencing men. When I consider how much 
ambition or avarice can accomplish in all those who once 
place themselves in this course of life, almost destitute of sen- 
sible and present attractions, I despair of nothing, and I hold 
that virtue would be infinitely more effective accompanied as 
it is by so many solid goods, if some happy revolution of the 
human race brought it for a day into demand and made it as 
it were fashionable. It is very certain that we could accustom 
the youth to find their greatest pleasure in the practice of vir- 
tue. And even grown up men could make themselves laws 
and a habit of conforming to them, which would influence them 
as strongly and with as much uneasiness if they were turned 
aside from them, as a drunken man would feel when he is 
prevented from going to the ale-house. I am very happy to 
add these considerations upon the possibility and even upon the 
ease of the remedies for our evils, in order not to assist in dis- 
couraging men from the pursuit of true goods by the mere 
exposition of our weaknesses.] 

§ 39. Pit. [Xearly everything consists in making constant 
the desire for true good.] And it rarely happens that any 
voluntary action is produced in us unless some desire accom- 
])anies it ; this is why loill and desire are so often confounded. 
])ut we must not regard the uneasiness ^\nch. makes a part of, 
<^r which at least accompanies most of the other passions, as 
( ntirely excluded in this case. For hatred, fear, anger, envy, 
.shame, have each their uneasiness, and thereby influence the 
will. I doubt if any one of these passions exists entirely alone. 
I believe indeed that it would be diffieult to find any passion 
unaccompanied by desire. I am sure, however, that wherever 



CH. xAi] ON HUMAN UNDEKSTANDING 199 

there is uneasiness there is desire. And as our eternity does 
not depend on the present moment, we look beyond the present, 
whatever be the pleasures which we actually enjoy, and desire, 
accompanying these glances anticipative of the future, always 
impels the will to follow ; so that even in the midst of joy 
that which maintains the action upon which the present pleas- 
ure depends, is the desire to continue it, and the fear of being 
deprived of it, and whenever a greater uneasiness than that 
takes possession of the mind it immediately determines the 
mind to a new action and the present pleasure is neglected. 

Th. [Many perceptions and inclinations concur in perfect 
volition, which is the result of their conflict. There are 
some imperceptible by themselves, whose mass makes an un- 
easiness which impels us without our seeing the cause; there 
are many joined together which tend to some object or which 
remove it, and then it is desire or fear accompanied also by 
an uneasiness, but which does not always go so far as pleasure 
or displeasure.^ Finally, there are impulses really accompanied 
by pleasure and by pain, and all these perceptions are either 
new sensations or ideas resting upon some past sensation 
(accompanied or not by memory), which renewing the attrac- 
tions these same images had in the preceding sensations, renew 
also the former impulses in proportion to the vividness of the 
idea. From all these impulses results at last the prevailing 
effort which makes the will complete. But the desires and 
tendencies which are perceived are often also called voli- 
tions though less complete, whether they prevail and influence 
or not. It is thus easy to believe that volition can have but 
little force without desire and without aversion (fidte) ; for 
such I believe we may call the opposite of desire. Uneasi- 
ness exists not only in the troublesome passions, as hatred, 
fear, anger, envy, shame, but further in their opposites, as 
love, hope, favor, and glory. We may say that whenever 
there is desire, there will be uneasiness ; but the contrary is 
not always true, because often one is in a state of uneasiness 
Avithout knowing what he wants, and then there is no full- 
grown desire.] 

§ 40. Ph. Ordinarily the most pressing of the uneasinesses 

1 Gerhardt adds : " ou deplaisir." — Tb. 



2()0 LHIIJNITZ'S CKITIQUE OF LOCKE [hk. ii 

wliii'li aiv jiulgvd capable of bi'ing- removed at that time deter- 
mines the will to action. 

Th. As the result of the balance makes the final deter- 
mination, 1 should think it may happen that the most press- 
ing uneasiness does not prevail; for though it might prevail 
over each of the opposed tendencies taken by themselves, the 
others united may overcome it. The mind can indeed use 
skilfully the dicliotomies in order to cause sometimes the one, 
sometimes the others, to prevail, as in an assembly we can 
cause one party to prevail by plurality of votes, according as 
we shape the order of the question. It is true the mind 
ought to look far into the future ; for in the moment of 
struggle there is no time to use these artifices. All that then 
makes an impression, bears hard upon the balance, and helps 
to form a com2)ound direction almost like that in mechanics, 
and which without some prompt diversion we cannot stop, 

Fertur equis auriga nee audit currus liabenas.i 

§ 41. Ph. If 3'ou ask further ivhat it is that arouses desire, 
I reply, hapjyiness and nothing else. Hajypiness and misery 
are the names of two extremes of whose utmost bounds we 
are ignorant. It is what "eye hath not seen, ear hath not 
heard, and the heart of man hath never conceived." ^ But both 
make in us lively impressions by means of different kinds 
of satisfaction and joy, of torment and sorrow, which for 
brevity's sake I comprehend under the names of pdeasure and 
liain, both of wdiich happen to the mind as w^ell as to the 
body, or, to speak more accurately, pertain only to the mind, 
although sometimes they originate in the mind upon the 
occasion of certain thoughts, and sometimes in the body 
from certain modifications of motion. § 42. Thus happiness, 
taken in its full extent, is the utmost j^leasure of wdiich we are 
capable, as misery, taken in the same way, is the greatest 
pain we can feel. And the lowest degree of what can be 
called happiness is that state, in which delivered from all 
pain, we enjoy such measure of present pleasure that we can- 
not be content with less. We call that a good which is 
adapted to produce in us pleasure, and we call that an evil 
which is adapted to produce in us pain. But it often happens 

1 Verg. Georg. 1 : 514. — Tk. 21 Cor. 2:9. — Tb. 



cii. xxi] ON HUMAN UNDERSTANDING 201 

that we do not so name it when one or another of these goods 
or of these evils is found in competition with a greater good 
or a greater evil. 

Th. [I do not know whether the greatest pleasure is possi- 
ble. I should think rather that it can grow infinitely ; for 
we know not how far our knowledge and our organs may 
be carried in all that eternity which awaits us. I should 
think then that happiness is a lasting pleasure ; which can- 
not exist without a continual progression to new pleasures. 
Thus of two, one of whom will advance incomparably more 
rapidly and by greater pleasures than the other, each will be 
happy in himself although their hajopiness will be unequal. 
Happiness is then so to speak a road through pleasures, and 
pleasure is only a step and an advance towards happiness, the 
shortest that can be made according to present impressions, 
but not always the best, as I said towards the end of § 36. 
One may miss the true road, in desiring to follow the short- 
est, as the stone going straight may meet too soon obstacles 
which prevent it from advancing directly towards the centre 
of the earth. Thus we know that it is the reason and the 
will which lead us towards happiness, but that feeling and 
appetite carry us only towards pleasure. Now although 
pleasure cannot receive a nominal ^ definition, any more than 
light or color, it can nevertheless receive like them a causal,^ 
and I believe that at bottom, pleasure is a feeling of perfec- 
tion and pain a feeling of imperfection, provided it be marked 
enough to make us capable of perceiving it : for the little 
insensible perceptions of a perfection or imperfection, which 
are like the elements of pleasure and pain, and of which I have 
spoken so many times, form the inclinations and propensities, 
but not yet the passions themselves. Thus there are insensi- 
ble inclinations and these we do not perceive; there are sensi- 
ble ones whose existence and object we know, but whose 
formation we do not feel, and there are confused inclinations 
which we attribute to the body, although there is always 
something corresponding in the mind; finally, there are dis- 
tinct inclinations, which reason gives us, ^whose force and 
formation we feel ; and the pleasures of this kind which are 
found in the knowledge and production of order and harmony 
1 Cf. New Essays, Bk. III., chap. 3, § 18. — Tr. 



202 



].i;iBNri//s c'luriQUE of locke [hk. 



arc the most estimable. You are right in saying that in 
ijeneral all these inclinations, passions, pleasures and pains 
U'long only to the ininil or soul ; I will add, indeed, that their 
origin is in the soul itself, taking things in a certain meta- 
physical strictness, but that, nevertheless, you are right in say- 
ing that confused thoughts come from the body, because 
thereupon the consideration of the body — and not that of 
the soul — furnishes something distinct and explicable. The 
good is that which conduces or contributes to pleasure, as the 
evil is that which contributes to pain. But in collision with a 
greater good, the good of which we should be deprived would 
become in truth an evil, in so far as it should contribute to 
the pain which would spring from it. 

§ 47. Ph. The soul has the power of suspending the accom- 
plishment of some of these desires, and is consequently at lib- 
ert}^ to consider one after another and to compare them. In 
this consists the freedom of man, and what we call, tliough in 
my view improperly, free-will ; and it is from the bad use we 
make of it that all this variety of mistakes, errors, and faults 
proceeds, into which we rush when we determine our will too 
promptly or too late. 

Th. The execution of our desire is suspended or stopped 
when this desire is not strong enough to move us and to over- 
come the trouble or inconvenience there is in satisfying it ; 
and this trouble consists sometimes only in an inactivity or 
insensible lassitude which discourages without our taking 
notice of it, and which is greatest in persons reared in indo- 
lence or whose temperament is phlegmatic, and in those who 
are discouraged by age or by poor success. But when desire 
is strong enough in itself to move, if nothing prevents it, it 
can be stopped by contrary inclinations ; whether they consist 
in a simple propensity Avhich is as it were the element or be- 
ginning of desire, or go as far as desire itself. But as these 
inclinations, these propensities, and these contrary desires S.re 
to be found already in the soul, it does not have them in its 
power, and consequently it could not resist them in a free and 
voluntary way in which the reason can share, if it had no 
other means of diverting the mind elsewhere. But how does 
it presume to do it in case of need ? For there is the point, 
especially when one is occupied with a very strong passion. 



CH. xxi] ON HUMAN UNDERSTANDING 203 

It is then necessary for the mind to be prepared in advance, 
and to find itself already in process of going from thonght to 
thought, in order not to hesitate too much at a slippery and 
dangerous step. It is well for that reason to accustom our- 
selves in general not only to think as it were in passing of 
certain things in order the better to preserve the freedom of 
the mind ; but it is better to accustom ourselves to proceed 
methodically, and to fasten ourselves to a train of thoughts 
whose connection reason and not chance (?'.e. insensible and 
casual impressions) makes. And for this purpose it is well 
from time to time to accustom ourselves to collect our thoughts 
and to raise ourselves above the present tumult of impres- 
sions, to go forth, so to speak, from the place where we are, to 
say to ourselves: ^' Die cur hie? respice finem,^ \y\\Q\:e are we 
then ? or let us come to the purpose,^ let us come to the point." 
Men would very often need some one officially appointed (as 
Philip, the father of Alexander the Great, had) to interrupt 
and call them to their duty. But in default of such an officer, 
it is well for us to be accustomed to render ourselves this ser- 
vice. Now being once in a condition to stop the effect of our 
desires and passions, i.e. to suspend (their) action, we can find 
means to combat them, Avhether by contrary desires or inclina- 
tions or by diversion, i.e. by occupations of another nature. 
It is by these methods and artifices that we become as it were 
masters of ourselves, and can make ourselves think and do at 
the time what we should wish to will and what reason com- 
mands. But it is always through determined paths, and never 
without a reason or by means of the imaginary principle of 
perfect indifference or equilibrium, in which some would make 
the essence of freedom to consist ; as if one could determine 
himself without a subject, and even against every subject, and 
go directly against the entire prevalence of impressions and 
propensities. Witliout a reason, I say, i.e. without the opposi- 
tion of other inclinations, or without being in advance dis- 
posed to turn aside the mind, or without any other means 
equally ex})licable ; (to act) otherwise is to recu^- to the chimer- 

1 Literally : Why are we here ? Consider tlie end ! — Tr. 

2 Erdniaun and Jacqnes omit: "ou venous au propos," fonnd in Ger- 
hardt.— Tr. 



2i»4 LKir.NlTZ'S CUiriQUE OF LOCKE [bk. ii 

ical, as in the empty faculties or occvilt qualities of the scho- 
lastics, iu which there is neither rhyme nor reason.] 

§ 48. Ph. [I am also for this intelligent determination of 
the will by what is in the perception and the understanding.] 
To will and do conformably to the final result of a sincere 
examination is rather a perfection than a defect of our nature. 
And this so far from being a suppression or an abridgement 
of freedom, is its greatest perfection and advantage. And the 
more we are prevented from determining ourselves in this 
way, the nearer we are to misery and slavery. In fact, if you 
supiwse in the mind a perfect and absolute indifference which 
cannot be determined by the final judgment which it makes of 
good or evil, you put it in a very imperfect state. 

Th. [All this is very much to my taste, and shows that 
the mind has not entire and direct power always to stop its 
desires, else it would never be determined, whatever examina- 
tion it might make, and whatever good reasons or efficacious 
sentiments it might have, and it would always remain irreso- 
lute and fluctuate eternally between fear and hope. It must, 
then, after all, be determined, and thus it could itself oppose 
only indirectly its desires, by itself preparing in advance the 
arms which fight them in time of need ; as I have just ex- 
plained.] 

Ph. But a man is at liberty to lift his hand to his head or 
to let it lie quiet. He is perfectly indifferent regarding either 
of these acts, and it would be an imperfection in him if he 
lacked that power. 

Til. [To speak accurately, one is never indifferent regard- 
ing two alternatives,^ whatever they may propose ; for exam- 
ple, turning to the right or the left,^ putting the right foot 
forward (as was necessary in the case of Trimalchio) or the 
left ; for we do the one or the other without thinking of it, 
and this is an indication that a concurrence of internal disposi- 
tions and external impressions (although insensible) deter- 
mines us to the side that we take. But the prevalence is very 

1 After "partis," Gerhardt reads: " quelsqu'on puisse proposer," which 
Erdmanu and Jacques omit. — Tr. 

2 After " gauche," Gerhardt reads : " de niettre le pied droit devant (comma 
il falloit chez Trimalcion) ou le srauche, "which Erdmann and Jacques omit. 
For the allusion c/. Petronius, Satyricon, chap. 30. — Tk. 



CH. XXI] ON HUMAN UNDERSTANDING 205 



small, and in case of need it is as if we were indifferent in this 
respect, since the least sensible subject which presents itself 
to us is capable of determining us without difficulty to one 
rather than to the other ; and although there is a little trouble 
in lifting the arm to raise the hand to the head, it is so small 
that we overcome it without difficulty ; otherwise, I admit it 
would be a great imperfection if man were less indifferent, 
and if he were wanting in power to determine easily to raise 
or not to raise his arm.] 

Ph. But it would be as great an imperfection if he had the 
same indifference on all occasions, as when he would defend 
his head or his eyes from a blow, by which he saw he was 
about to be struck. [That is to say, it were as easy for him 
to stop this movement as others of which we have just spoken, 
and in which he is almost indifferent ; for that would make 
its influence insufficiently strong and prompt in time of need. 
Thus determination is useful to us, and, indeed,^ very often 
necessary ; for if we were less determined on every sort of 
occasion, and as it were insensible to reasons drawn from the 
perception of good or evil, we would be without effective 
choice.] And^ if we were determined by something else than 
the final result, which we have formed in our own mind accord- 
ing as we have judged a certain action good or evil, we should 
not be free. 

Th. [Nothing is truer, and those who seek another free- 
dom know not Avhat they ask.] 

§ 49. Ph. The superior beings who enjoy perfect happi- 
ness are determined in the choice of the good more strongly 
than we, and yet we have no reason to think them less free 
than ourselves. 

Th. [For this reason theologians say that these blessed 
substances are confirmed in the good and exempt from all 
danger of falling.] 

Ph. I believe indeed that, if it were proper for poor finite 
creatures like ourselves to judge of what an infinite wisdom 
and goodness could do, we could say that God himself can- 
not choose what is not good, and that the freedom of this all 

1 Gerbardt omits " nierae," which Erdmaiin and Jacques insert after 
"et."— Tr. 

2 Gerhardt reads : " et " ; Erdinann and Jacques, " comiue." — Tk. 



■2M LKlliMTZ'S ClUTlCiUE UF LOCKE [i3k. ji 



poworful being docs not liinder him from being determined by 
what is best. 

Th. [I am so persuaded of this truth that I believe we can 
boldly assure ourselves of it, wholly poor and finite creatures 
that we are, and that we should be very wrong in doubting 
it; for by so doing we should derogate from his wisdom, 
goodness and other infinite perfections. But choice, however 
determined the will be, should not be called necessarily and 
rigorously absolute; the prevalence of perceived good in- 
clines without necessitating, although considered as a whole, 
this inclination is determinate and never fails to produce its 
effect.] 

§ 50. Ph. To be determined by the reason to the best, 
is to be the freest. Who would wish to be foolish for the 
reason that a fool is less determined by wise reflections than 
a man of good sense ? If freedom consists in throwing off 
the yoke of reason, fools and madmen will be the only free- 
men; but I do not believe that for love of such freedom 
any one would wish to be a fool, save he who is one already. 

TJi. [There are people to-day who consider it clever to 
declaim against reason, and to treat it as an inconvenient 
pedant. I see little books, discourses about nothing, which 
make great pretensions, and I sometimes see verses even too 
beautiful to be employed in such false thoughts. In fact, 
if those who mock at reason spoke in earnest, it would be a 
new kind of extravagance unknown to past centuries. To 
speak against reason is to speak against truth ; for reason is a 
concatenation of truths. It is to speak against one's self, 
against one's good, since the principal point of reason con- 
sists in knowing the truth and following the good.] 

§ 51. Ph. As then the highest perfection of an intelligent 
being consists in applying himself carefully and constantly to 
the search for true happiness, so the care we should employ 
not to take as real happiness that which is only imaginary, is 
the foundation of our freedom. The more we are bound to 
the invariable search for happiness in general ivhich never 
ceases to he the object of our desires, the more our will finds 
itself freed from the necessity of being determined by the 
desire which bears us towards some particular good, until we 
have examined Avhether it agrees with or is opposed to our 
true happiness. 



CH. XXI] ON HUMAN UNDERSTANDING 207 

Til. The true good should always be the object of our 
desires, but there is room for doubt whether it is so : for often 
one thinks but little of it, and I have remarked here more 
than once, that unless appetite is guided by Iteason ib tends to 
present pleasure and not to happiness, i.e. to enduring pleas- 
vire, although it tends to protract it ; see § 36 and § 41. 

§ 53. Pli. If some extreme disturbance takes entire pos- 
session of our mind, as the pain of a cruel torture, we are not 
enough masters of our mind. But in order to control our^ 
passions as much as possible, we should make our mind relish 
good and evil really and effectively, and not permit an ex- 
cellent and considerable good to escape our mind without leav- 
ing there some relish, until we have excited in ourselves 
desires proportioned to its excellence so that its absence 
renders us uneasy as well as the fear of losing it when we 
enjoy it. 

Th. [That sufficiently agrees Avith the remarks I have 
just made in §§31 and 35, and with what I have said more 
than once of luminous pleasures, where we understand how 
they improve us without putting us in danger of some greater 
imperfection, as do the confused pleasures of sense, against 
which we must guard ourselves, especially when we have not 
learned by experience that we shall be able surely to avail 
ourselves of them.] 

Ph. And let no one say here that he cannot master his pas- 
sions nor hinder them from breaking loose and forcing him to 
act ; for what he can do before a prince or great man, he can 
do, if he will, when alone or in the presence of God. 

Th. [That remark is very good and worthy of frequent 
reflection.] 

§ 54. Ph. But the different choices men make in the world, 
prove that the same thing is not equally good for each of 
them. And if the interests of men did not extend beyond 
this life, the reason of this diversity which causes, for exam- 
ple, these to plunge into luxury and debauchery, and those to 
prefer temperance to pleasure, would arise onl}^ from the fact 
that they placed their happiness in these different things. 

Th. [It arises thence even now, although they all have or 
should have before their eyes this common object of the 
future life. It is true that the consideration of true happi- 



o„s LKIBNITZ'S CRITIQUE OF LOCKE [uiv. ii 

ness, oven in this life, should suffice to make those who dis- 
card it prefer virtue to pleasure ; although the obligation 
would not then be so strong or so decisive. It is also true 
that men's tastes are different, and it is said that we should 
not dispute about tastes. But as these are only confused per- 
ceptions, we should hold fast to them only in the case of ob- 
jects found to be indifferent and incapable of harm ; otherwise, 
if one had a relish for poisons which w^ould kill him or render 
him miserable, it would be ridiculous to say that his taste 
should not be called in question.] 

§ 55. Ph. If there is nothing to hope for beyond the grave, 
the inference is certainly very just : let us eat and drink, let 
us enjoy all that gives us pleasure, for to-morroiv ice die. 

Til. [There is something to be said, in my opinion, regard- 
ing this inference. Aristotle and the Stoics and many other 
ancient philosophers held another view, and I believe, indeed, 
that they were right. If there were nothing beyond this life, 
the peace of the soul and health of the body would not cease 
to be preferable to the pleasures Avhich would be contrary 
thereto. And it is no reason whatever for neglecting a good 
because it will not endure forever. But I admit that there 
are cases where there would be no means of demonstrating 
that the most virtuous course would be the most useful. It is 
then the thought of God and of immortality only which ren- 
ders the obligations of virtue and justice absolutely indispen- 
sable.] 

§ 68. Ph. It seems to me that the present judgment we 
make of good and evil is always right. And as for present 
happiness or misery, when reflection goes no farther, and all 
consequences are wholly put aside, man never chooses amiss. 

Th. [That is to say, if everything were limited to the pres- 
ent moment, it wou-ld not be right to refuse the pleasure which 
presents itself. In fact, I remarked above that all pleasure is a 
feeling of perfection. But there are certain perfections which 
bring with them greater imperfections. If some one devoted 
himself during his entire life to throwing peas against pins, in 
order to learn not to fail to make them pierce them, after the 
example of him to whom Alexander the Great caused to be 
given as a recompense a bushel of peas, this man would attain 
a certain perfection, but very slight and unworthy of being 



CH. XXI] ON HUMAN UNDERSTANDING 209 

compared with so many other very necessary perfections 
which he would have neglected. Thus the perfection which 
is found in certain present pleasures should yield especially 
to the regard for the perfections which are necessary ; in order 
that we be not plunged into misery, which is the state in 
which we go from imperfection to imperfection, from pain to 
pain. But if there be only the present, it would be necessary 
to be contented with the perfection which is present, i.e. with 
present pleasure.] 

§ 62. Ph. No one would voluntarily render his condition 
unhappy unless he were led by false judgments. I do not 
speak of mistakes which are the result of invincible error, 
and Avhich scarcely deserve the name of false judgment, but 
of that false judgment which every man must confess in 
himself to be such. § 63. In the first place, then, the soul 
is mistaken when we compare present pleasure or pain with 
one to come which we measure by the different distance at 
which they are found with respect to us ; like a spendthrift 
heir Avho for the present possession of a little something 
would renounce a large heritage, which could not fail him. 
Every one should recognize this false judgment, for the future 
will become present, and will then have the same advantage 
of nearness. If at the moment the man takes the glass in 
his hand, the pleasure of drinking were accompanied with the 
headache and pains in the stomach, which will follow in a 
few hours, he would not in the least wish to taste the wine. 
If a little difference in time causes so much illusion, with 
much stronger reason a greater distance will produce the 
same effect. 

Til. There is some congruity here between the distance 
of places and that of times. But there is also this difference, 
that visible objects diminish their action upon the sight 
very nearly in proportion to their distance, and it is not 
at all the same as regards the future objects which act upon 
the imagination and the mind. Visible rays are straight 
lines proportionally distant, but there are curved lines which 
after some distance appear to fall into the straight line 
and are no longer sensibly divergent: thus are made the 
asymptotes, whose apparent interval diverges from the straight 
lines, although in the truth of things they abide eternally 
p 



ilO LEIBNITZ'S CRITIQUE OF LOCKE [bk. n 



separate. We find indeed that at last the appearance of ob- 
jects does not diminish in proportion to the increase of the 
distance, for tlie appearance soon^ disappears entirely al- 
though the distance be not infinite. Thus a short distance of 
time robs us entirely of the future, as if the object had en- 
tirely disappeared. There often remains only the name in 
the mind and that kind of thoughts of which I have already 
spoken, which are surd, and incapable of making an impres- 
sion, unless you have attended to them methodically and 
habitually.] 

Ph. I do not speak here of that kind of false judgment 
by which what is absent is not only diminished but suddenly 
annihilated in men's minds, when they enjoy all they can 
obtain for the present, and then conclude that no evil will 
happen to them. 

Til. [It is another kind of false judgment when the expec- 
tation of good or evil to come is annihilated, because the 
result drawn from the present is denied or made doubtful; 
but beyond that, the error which annihilates the thought of 
the future is the same thing as this false judgment of which 
I have already spoken, which arises from a too feeble repre- 
sentation of the future, which is considered only a little 
or not at all. For the rest, we might perhaps distinguish 
here between bad taste and false judgment, for often we 
do not even question whether the future good should be pre- 
ferred, and act only upon impression without presuming to 
come to the examination. But when we think, one of two things 
happens, either we do not continue suflB.ciently our thought, 
and we pass on Avithout pressing the question which has 
been touched ; or we pursue the examination and form a 
conclusion. And sometimes in each case there remains greater 
or less self-condemnation : sometimes also there is no formido 
oppositi or scrupulousness at all, whether the mind turns aside 
at once, or is deceived by its prejudices.] 

§ 64.^ Ph. The limited capacity of our mind is the cause 
of the false judgments we make in comparing good and evil. 
We cannot well enjoy two pleasures at once, and still less can 

^ Gerhardt reads after " entieremeiit," "bientost," which Erdinann and 
Jacques omit. — Tr. 

2 Gerhardt. So also Lonlve, Philos. Works, Vol. 1, p. 402'(Bohii ed.). Erd- 
mann has § 29 : Jacques, § 59. — Tr. 



CH. XXI] ON HUMAN UNDERSTANDING 211 

we enjoy any pleasure in the time that we are beset by pain. 
A little bitterness mixed in the cup prevents us from tasting 
its sweetness. The evil we feel is always the worst ; we cry : 
Ah ! any other pain rather than this ! 

Th. [There is much variety in all this according to men's 
temperaments, the force of their feelings, and the habits they 
have contracted. A man who has the gout might be joyful 
because a large fortune fell to him, and a man who swims in 
delights, and who might live at his ease upon the earth, is 
{)lunged into sadness because of a disgrace at court. The fact 
is, joy and sadness arise from the result or from t\iQ prevalence 
of pleasures or pains, when there is a mixture of them. Lean- 
der scorned the inconvenience and danger of swimming over 
the sea at night, urged on by the attractions of the beautiful 
Hero.^ There are people who can neither drink nor eat^ nor 
satisfy other appetites without much pain, on account of some 
weakness or inconvenience ; and yet they satisfy these appe- 
tites even beyond necessity and just limits. Others are so 
effeminate or so delicate that they refuse pleasures with which 
any pain, disgust or any inconvenience is mingled. There 
are some persons who bravely place themselves beyond pains 
and pleasures present and ordinary, and. act almost alone 
through fear and hope. Others are so effeminate that they 
complain of the least inconvenience, or run after the least sen- 
sible and present pleasure nearly like children. These are 
the people to whom the present pain or pleasure always ap- 
pears the greatest ; they are like preachers or panegyrists of 
little judgment, with whom, according to the proverb : The idol 
of the day is always the greatest saint of paradise.^ But what- 
ever variety is found among men, it is always true that they 
act only according to present perceptions, and when the future 
impresses them, it is always by means of an image they have 
of it, or by resolution and habit which they have contracted 

1 Cf. Vergil, Georcj. 3, 258; Ovid, Heroides, 18, 19 (17, 18, Ovid. Opera, ex 
rccog. Rud. Merkelii, Vol. 1, p. 141 sq., Lipsise : B. G. Teubner, 1887) ; and, for 
" the final form "of " this poem of love and death," the poem of 340 hexameters 
by Miisffius, the grammarian of the fifth century a.d., an extended abstract of 
which is given in J. A. Symonds' Studies of the Greek Poets, Vol. 2, chap. 22, 
pp. 345-362. New York : Harper & Bros., 1880. — Tr. 

2 Gerhardt reads after "manger," " ou qni ne sanroient satisfaire d'autres 
appetits," which Erdmann and Jacques omit. — Tr. 

3 The italics are mine. — Tr. 



•212 LEIBNIl'Z'S CKITIQUE OF LOCKE [hk. ii 



in following even a simple name or other arbitrary cliaracter, 
without liaving any picture or natural sign, because it would 
not be without uneasiness, and sometimes without a feeling of 
chagrin, that they would oppose themselves to a strong reso- 
lution already made, and, above all, to a habit.] 

§ G~K Ph. 'Men are apt enough to diminish future pleasure, 
and to conclude in themselves that, when it comes to trial, it 
may perhaps not correspond to the hope it gives nor to the 
opinion they generally have of it ; having often found by their 
own experience that not only the pleasures which others have 
magnified have appeared to them very insipid, but that what 
has caused themselves much pleasure at one time, has offended 
and displeased them at another. 

Th. [These are mainly the reasonings of voluptuaries, but 
we ordinarily find that the ambitious and avaricious judge 
wholly otherwise honors and wealth, although they enjoy 
only moderately, and often, indeed, very little, these same 
goods when they possess them, being always occupied in going 
farther. I find it a beautiful invention of nature's architect 
to have rendered men so sensible to what appeals so little to 
their senses ; and if they could not become ambitious or avari- 
cious, it would be difficult in the present state of human nature 
for them to be able to become virtuous and reasonable enough 
to labor for their perfection in the face of the present pleas- 
ures which turn them aside from it. 

§ 66. Ph. As to things good or bad in their consequences 
and by their aptness to procure us good or evil, we judge 
them in different ways ; either when we judge them incapable 
of really doing us as much evil as in fact they do, or when 
we judge that while the consequence is important it is not so 
certain that it may not happen otherwise, or at least that it 
may not be avoided by some means, as by industry, address, 
change of conduct, repentance. 

Th. It seems to me that if by the importance of the conse- 
quence we understand that of the consequent, i.e. the great- 
ness of the good or evil that may follow, we must fall into the 
preceding kind of false judgment, in which future good or 
evil is poorly represented. Thus there remains only the sec- 
ond kind of false judgment, of which we shall presently treat, 
namely, that in which the consequence is doubtful.] 



cii. xxi] ON HUMAN UNDERSTANDING 213 

Ph. It would be easy to shoAv in detail that the subterfuges 
which I have just alluded to are so many unreasonable judg- 
ments ; but I shall content myself with remarking in general 
that it is acting directly contrary to reason to hazard a greater 
good for a less [or to expose^ ourselves to misery in order to 
acquire a little good or to avoid a little evil], and that, too, 
upon uncertain conjectures and before we have entered upon a 
due examination. 

Tli. [As these are two. heterogeneous considerations {i.e. 
considerations which cannot be compared with each other), 
that of the greatness of the consequence and that of the 
greatness of the consequent, moralists in desiring to compare 
them are much perplexed, as appears in the case of those who 
have treated of probability. The truth is that here as in 
otlier estimates disparate and heterogeneous and, so to speak, 
of more than one dimension, the greatness of that which is 
discussed is in reason composed of both estimates, and is like a 
rectangle, in which there are two considerations, viz. that of 
length and that of breadth ; and, as for the greatness of the 
consequence and the degrees of probability, we still lack that 
part of Logic which is to estimate them,- and the most of the 

1 Gerhardt reads : " exposer " ; Erdmann and Jacques : " opposer." — Tb. 

2 I.e. the Calculus of Probabilities, the founder of which was Pascal, 
1023-1062, who developed the mathematical theory of probability iu his cor- 
respoudeuce with Fermat, l()01-l(iG5, concerning certain questions on the 
equitable division of the stakes in games of chance proi^osed to Pascal by the 
Chevalier de Mere. Cf. I. Todhunter, History of the Theory of Probability 
from the time of Pascal to that of Laplace, pp. 7-21, 8vo. Cambridge and 
London, LSfiS. Contributions were made to the theory by many of the dis- 
tinguished mathematicians of the period and after, including James Bernoulli, 
1()54-1705; Huygens (vid. ante, p. 150, note 3) ; Demoivre, l&il-llM, in his 
Doctrine of chances, or method of calcidatimj the probabilities of events at 
play, 3ded., London, 1756; Laplace, 1749-1827, in his Th^orie analytiqne des 
probabilite's (Vol. 7 of his CEuvres completes, pvbliees sous les auspices de 
I'Arademie des Sciences, seven vols., 4to Paris, 1878-1886), since which 
Imt little advance has been made in the theory; and Poisson, 1781-1840, in 
liis Eccherchcs sur la jirobabilite des jiu/ements en matieres criminelles, etc., 
4to Paris, 18.37. Leibnitz became acquainted with Pascal's labors during 
his residence in Paris, 1672-1676; cf. Guhrauer, Leibnitz. Leben, 1, 113 sq. 
He recognized the immense importance of this new " part of Logic," and 
thought to substitute it for the old and crude casuistry which had so long 
]>revailed. In the letter to Bourguet, March 22, 1714, Gerhardt, 3, 570; Erd- 
mann, 723, Leibnitz glances briefly at the historical rise of tlie calculus of 
]n-o1iiibilities. For the pliilosophical side of the question, cf. J. S. Mill, Lor/ic, 
Bk. HI., chaps 18, 23, pp. .")7!> sq., 41() sq., 8tli cd., Harper and Bros., New 



2U LEIBNITZ'S CHITIQUE OF LOCKE [inc. n 



casuists who have written on probability have not even under- 
stood its nature, founding it with Aristotle,^ upon authority, 
instead of founding it as they ought upon likelihood (vraisevi- 
bhiuce), authority being only one of the reasons which pro- 
duce likelihood.] 

§ G7. Ph. Here are some of the ordinary causes of this 
false judgment. First, ignorance, second, inattention, when a 
man does not reflect upon that of which he is aware. This 
is an affected and present ignorance which misleads the judg- 
ment as well as the will. 

Th. [It is always present, but not always affected ; for we 
do not always take it into our heads to think, when it is 
necessary, of what we know and the memory of which we 
should recall if we were master of it. Affected ignorance is 
always mixed with some attention at the time it is affected ; in 
the future, it is true, it may ordinaril}^ include somewhat of in- 
attention. The art of thinking in time of need of what we know 
would be one of the most important if it were found ; but I 
do not see that men up to the present time have even thought 
of forming the elements of it, for the art of memory^ of 
which so many authors have written is wholly another thing.] 

Ph. If then they bring together in confusion and hastily 
the reasons from one side and allow through neglect several 
sums which ought to enter into the reckoning to escape, this 

York, 1881; F. H. Bradley, The Principles of Logic, Bk. I., chap. 7, §§ 32 
sq., pp. 201 sq., Kegau Paul, Trench and Co., London, 1883; J. Venn, The 
Logic of Chance, 3d ed., Macmillan and Co., London, 1888; W. S. Jevons, The 
Principlea of Science, 3d ed., Macmillan and Co., London, 1889. — Tr. 

1 For Aristotle's definition of probability, cf. Anal. Prior., II., 27, 70^3: 
"The probable is a generally admitted pro]3osition. For -what is known for 
the most jjart as thus happening or not happening, or being or not being, this 
is probable "; '■/. also Wallace, Outlines, § 21, who quotes the Greek of the 
pas.sage. Phet.L, 2, 1.3.57*34: "For the probable is that which for the most 
part happens." Aristotle accordingly rests much more upon experience 
than upon authority, and Leibnitz has not given his definition accurately. 
"The probable conclusion," says Schaarschmidt, is for Aristotle, "an incom- 
plete induction, whose problematic character he well understood, but did not 
determine more closely. Later Greek philosophers of a sceptical creed began 
to speak of grades of probability, but the moderns have been the first to 
fall upon the fruitful thoughts of a mathematical estimate of probability." 
— Tr. 

2 Mnemonics, the invention of which was ascribed to the poet Simonides, 
of Ceos, 5.56^169 B.C., perhaps because he was famous for the strength of his 
own memory. Cf. Cicero, De Oratore, Bk. II., chap. 82. — Tr. 



cii. XXI] ON HUMAN UNDERSTANDING 215 

haste produces no less false judgments than if it were perfect 
ignorance. 

Th. [In reality many things must be taken into account, as 
should be the case, when the balance of reasons is discussed ; 
and the process is almost like that in the account-books of 
merchants. For no sum must be neglected, each must be 
properly estimated by itself, they must be properly arranged, 
and finally an exact collection must be made of them. But 
we neglect many weighty points either by its not occurring to 
us to think of them or by passing lightly over them ; and we 
do not give each its proper value, like the book-keeper, who 
was careful properly to calculate the columns of each page, 
but who calculated very badly the particular sums of each 
line or posting, before putting them in the columns ; this 
causes the examiners to be deceived, who look principally at 
what is in the columns. Finally, after having carefully noted 
all, they may be deceived in the collection of the sums of the 
columns and even of the final collection, in which is the sum 
of the sums. Thus we should still need the art of thinking 
and that of estimating probabilities, and besides the knowl- 
edge of the value of goods and evils in order properly to 
employ the art of consequences ; and furthermore, attention 
and patience would be necessary after all that, in order to 
push to the conclusion. Finally, a firm and constant resolu- 
tion to execute the conclusion arrived at is necessary ; and 
address, method, particular laws, and habits entirely formed 
in order to maintain the course in the future, when the con- 
siderations, which have caused it to be taken, are no longer 
present to the mind. It is true, thank God, that in what is of 
the greatest importance and which concerns the siimmam 
renim, hajipiness and misery, there is no need of so much 
knowledge, aid, and address, as it would be necessary to have 
in order properly to judge in a council of state or of war, in 
a tribunal of justice, in a medical consultation, in some theo- 
logical or historical controversy, or in some point of mathe- 
matics or mechanics ; but as a recompense more firmness and 
habit is necessary, in what concerns this great point of fe- 
licity and virtue, in order always to adopt good resolutions 
and to follow them. In a word, for true happiness less 
knowledge suffices with more good will ; so that the greatest 



jia l,i:il5NITZ'S CUirKiUK of LOCKE [hk. 



idiot may attain it as easily as the most learned and most skil- 
ful.] 

I'h. You see then that without liberty the understanding 
wouhl be of no use, and that liberty without understanding 
would signify notliing. If a man could see what may do him 
good or evil without being able to move a step in advance 
towards the one or in removal from the other, would he be 
the better for the sight ? He would be indeed more miserable 
for this reason, for he would uselessly pine after the good and 
would fear the evil, that he sees is inevitable ; and he who is 
at liberty to run here and there in the midst of perfect dark- 
ness, in what respect is he better than if he were tossed about 
at the pleasure of the wind ? 

Th. [His caprice would be a little better satisfied, but he 
would be in no better condition to meet good or to shun evil.] 

§ 68. Fh. Another source of false judgment. Content with 
the first pleasure which comes to hand or which custom has 
rendered agreeable, we do not look farther. This then is 
also an occasion for men to judge wrongly when they do not 
regard as essential to their happiness that which really is so. 

Th. [It seems to me that this false judgment is comprised 
under the preceding kind where one is mistaken as to the 
consequences.] 

§ G9. Ph. The inquiry remains whether a man has the 
power to change the pleasure or displeasure which accom- 
panies any particular action. In many cases he can. ^len 
may, and ought to, correct their palates and make them acquire 
a taste. They can change also the taste of the soul. A due 
consideration, practice, application, custom will bring about 
this result. Thus it is that men accustom themselves to 
tobacco, which usage or custom at last makes them find agree- 
able. It is the same as regards virtue. Habits have powerful 
charms and we cannot depart from them without uneasiness. 
You will, perhaps, regard it as a paradox that men can make 
things or actions more or less agreeable to themselves, so much 
do they neglect this duty. 

Th. [I have already made this statement above, § 37, 
towards the end, and § 47, also towards the end. We can 
make ourselves will anything and form our taste.] 

§ 70. Ph. Morality, established upon true foundations, can 



CH. XXI] ON HUMAN UNDERSTANDING 217 

only diitermine to virtue : it suflfices that infinite happiness 
and misery after this life are possible. We must admit that 
a good life, joined with the expectation of possible eternal 
felicity, is preferable to a bad life, accompanied by the fear of 
terrible misery, or, at least, of the terrible and uncertain hope 
of annihilation. All this is in the highest degree self-evident, 
although virtuous men should have only evil to endure in this 
world, and the wicked should taste therein perpetual pleas-- 
ure, which is ordinarily quite otherwise. For rightly consid- 
ering all things, I believe they have the worst part even in 
this life. 

Th. [Thus were there no life beyond the grave an epicurean 
life would not be the most reasonable. And I rejoice, sir, that 
you rectify what you said to the contrary above, § 55.]. 

Ph. Who could be so foolish, as to resolve (if he had his 
senses) to expose himself to a possible danger of being infin- 
itely unhappy so that he has nothing to gain therefrom for 
himself but pure annihilation ; instead of putting himself in 
the condition of the good man who has nothing to fear but 
annihilation, and who has eternal felicity to hope for ? I 
have forborne to speak of the certainty or probability of the 
future state, because I have no other design in this place than 
to show the false judgment of which each should acknowledge 
himself guilty on his own principles. 

Th. [The wicked are very prone to believe that the other 
life is impossible. But they have no reason for their belief 
other than that which compels them to limit themselves to 
what they learn by their senses, and that no one to their 
knowledge has come back from the other world. There was a 
time when upon the same principle we could reject the anti- 
podes, when we were unwilling to unite mathematics and the 
popular notions ; and we could do so with as much reason as 
we can now have in rejecting the other life, when we are 
unwilling to unite true metaphysics and the notions of the 
imagination. For there are three degrees of notions or ideas, 
viz. : popular, mathematical, metaphysical. The first do not 
suffice to make us believe in the antipodes ; the first and the 
second do not yet suffice to make lis believe in the other 
world. It is true they furnish already favorable conjectures ; 
but if the second established certainly the antipodes before 



»18 l.KULMTZ'S CKirUiUE OF LUCKE [inc. ii 



tlie expiTifiK-e we now have of it (I speak not of the inhabi- 
tants, but of the phiee at least which the knowledge of the 
roundnoss of the earth gave them among geographers and 
a.stronomers-), the last give no less certitude of another life 
from this time, and before you have gone to see.] 

§ 72. Ph. Let us now return to power which is properly 
the subject of this chapter, liberty being only one form of it, 
but the most important. In order to have more distinct ideas 
of power, it will be neither beside the purpose nor useless to 
obtain a more exact knowledge of what is called action. I 
said at the beginning of our discourse on power that there 
are two kinds of actions, of which we have some idea, viz. : 
motion and thought.^ 

Th. [I thought you could avail yourself of a more general 
term than that of thought, viz. : that of perception, attributing 
thought only to minds, Avhile perception belongs to all the 
entelechies. But I do not wish, however, to contest with any 
one the liberty to take the term thought in the same general 
way. And for myself indeed I shall perhaps do so some time 
without being aware of it.] 

Ph. iSTow, although we give to those two things the name of 
action, we shall find however that it does not always suit them 
perfectly, and that there are some examples which we shall 
recognize rather as passions. For in these examples sub- 
stance, in which we find movement or thought, receives purely 
from without the impression through which action is com- 
municated to it, and acts only by the sole capacity it has 
of receiving this impression, which is only a passive power. 
Sometimes substance or the agent puts itself in action by its 
own power, and it is there properly an active poiver. 

Til. I have already said that, taking action in metaphysical 
strictness as that which takes place in substance spontaneously 
and from its own depths, that alone is, properly speaking, a 
substance which is active,^ for all arises for it from itself after 
God ; it being impossible for one created substance to have 

1 Locke has: "thinking," Philos. Works, Vol.l,p.413 (Bohn'sed.).— Tr. 

2 Cf. De ipsa natura, etc., 1698, § 9 ad fin.; Gerhardt, 4, 509; Erdmann, 
157; Jacques, 1, 461 (in French); J. H. v. Kirchmann, Die klein. philos. 
wicht. Schrift. V. G. W. Leibniz (Philos. Bibliothek, Bd. 81), p. 121 (in Ger- 
man), ErickKoschny, Leipzig, 1879; also Kuno Fischer, Ge.Hch. d. neuern Philos., 
Vol. 2 (G. W. Leibniz), p. 334, 3d ed., Heidelberg: C. Winter, 1889. — Tk. 



cii. XXI] ON HUMAN UNDERSTANDING 219 

influence upon another. But taking action as an exercise of 
perception and jmssion as its contrary, there is action in true 
substance only wlien their perception (for I grant it to all) is 
developed and becomes more distinct, as there is passion only 
when it becomes more confused ; so that in substances capable 
of pleasure and of pain, all action is a step towards pleasure 
and all passion a step towards jiain. As for motion, it is 
only a real phenomenon, because matter and mass to which 
motion belongs is not properly speaking a substance. But 
there is an image of action in motion as there is an image of 
substance in mass ; and in this respect we can say that the 
body acts (agit) when there is spontaneity in its change and 
that it is j^cissive (patit) when it is urged on or hindered by 
another ; as in the veritable action or passion of a veritable 
substance we may take as its action, and attribute to itself, 
the change by which it tends to its perfection. And in the 
same manner we can take as |>assjon and attribute to a 
foreign cause the change by which the contrary happens to it ; 
although this cause is not immediate, because, in the first case, 
the substance itself, and in the second the foreign things serve 
to explain this change in an intelligible way. I allow bodies 
only an image of substance and action, because that which is 
composed of parts cannot pass, to speak accurately, as one 
substance, any more than a flock ; but we can say that there 
is therein something substantial, of which the unity, that 
which makes it as it were one being, comes from thought.] 

Ph. I have thought that the power to receive ideas or 
thoughts by the operation of some foreign substance was 
called power of thought, although at bottom it is only a pas- 
sive p)oioer or a simple capacity making abstraction from the 
reflections and internal changes which always accompany the 
.received image, for the expression,^ which is in the soul is, as 
it should be, that of a living mirror ; but the power which we 
have of recalling absent ideas at our choice, and of comparing 
together those that we think to the purpose, is truly an active 
poiver. 

Th. [This also agrees with the notions I have just pre- 
sented, for there is in this a passage to a more perfect state. 

1 Gerhardt and Erdmaim read; " I'expressiou " ; Jacques: " I'impres- 
sion." — Tk. 



220 LEIBNITZ'S CRITIQUE OF LOCKE [luv. u 



But I should suppose that there is also action in sensations so 
far as they give us more distinct perceptions and consequently 
the opportunity of making remarks and so to speak of devel- 
oping ourselves.] 

§ 73. Ph. Is^ow I think it appears that we can reduce the 
primitive and original ideas to this small number : extension, 
soUdUrj, mobility {i.e. passive power, or rather capacity of 
being moved), which come to us in the mind by way of reflec- 
tion, and finally, existence, duration, and number, which come 
to us by the two ways of sensation and reflection ; for by 
these ideas we could explain, if I am not mistaken, the nature 
of colors, sounds, tastes, odors, and all the other ideas we 
have, if our faculties were subtile enough to perceive the dif- 
ferent motions of the minute bodies which produce these sen- 
sations. 

Th. To speak the truth, I believe that these ideas, which 
you here call original and primitive, are for the most part not 
wholly so, being susceptible in my view of further resolution ; 
but I do not blame you at all, sir, for having limited yourself 
and for not having pushed the analysis farther. Moreover,^ I 
believe that if their number can be diminished by this means, 
it can be increased by adding other ideas more original or as 
much so. As to the question concerning their arrangement, I 
should consider, following the order of the analysis, exist- 
ence anterior to the others, number to extension, duration to 
motioity or mobility ; although this analytic order is not 
ordinarily that of the occasions which make us think of them. 
The senses furnish us the material for reflection and we should 
not even think of thought, if we did not think of something 
else, i.e. of the particular things which the senses furnish. 
And I am persuaded that created souls and minds are never 
without organs and never without sensations, as they cannot 
reason without characters. Those who have desired to main- 
tain a complete separation and mode of thinking in the sepa- 
rated soul, inexplicable by all that we know, and separated 

1 Gerhardt reads: "D'ailleurs je crois que si le nombre en pourroit estre 
diminue par ee moyen, il pourroit estre augmente," etc. ; Erdmann and Jacques 
read : "D'ailleurs si e'est vrai, que le nombre en pourroit etre diminue' par ce 
moyen, je crois qu'il pourroit etre augumente en y ajoutant d'autres Idees 
plus originales ou autaut." — Tk. 



cii. xxii] ON HUMAN UNDERSTANDING 221 

not only from our present experiences, but, what is much 
more, from the general order of things, have given too much 
influence to so-called strong minds, and have made the finest 
and the grandest truths objects of suspicion to many people, 
having indeed deprived themselves thereby of some excellent 
means of proving them, which this order furnishes us.] 



CHAPTER XXII 

OF MIXED MODES 

§ 1. Ph. Pass we on to the mixed modes. I distinguish 
them from the more simple modes, which are composed only of 
simjile ideas of the same kind. Moreover, the mixed modes 
are certain combinations of simple ideas wliich are not re- 
garded as characteristic marks of any real being, which has a 
fixed existence, but as scattered and independent ideas which 
the mind joins together; and they are thereby distinguished 
from the complex ideas of sitbstances. 

Th. [Properly to understand these we must recall our for- 
mer divisions. "According to you ideas are simple or complex. 
The complex are either substances, modes, or relations. Modes 
are either simple (composed of simple ideas of the same kind) 
or mixed. Thus, in your view, there are simple ideas, ideas 
of modes, both simple and mixed, ideas of substances and 
ideas of relations. We could, perhaps, divide the terms or 
the objects of ideas into abstract and concrete ; the abstract 
into absolute and into those which express relations ; the 
absolute into attributes and into modifications ; both into 
simple and composite ; the concrete into substances and into 
substantial things, made up of or the resultants of true and 
simple substances.] 

§ 2. Ph. The mind is purely passive, respecting its simple 
ideas, which it receives as sensation and reflection present 
them to it. But it often acts by itself, indeed, in reference 
to the mixed modes, for it can combine the simple ideas in 
making com})lex ideas without considering whether they so 
exist united in nature. This is why we give to these kinds of 
ideas the name of notion. 



LKIBNITZ'S CIUTIQUE OF LOCKE [bk. ii 

Th. [But reflection which makes us think of simple ideas 
is often voluntary also, and, moreover, the combinations, which 
naluri' has not made, can })r()duce themselves iu us, as it were 
in dreams and reveries by means of memory alone, without 
the mind's acting more than in the simple ideas. As for the 
term notion, many apply it to all sorts of ideas or conceptions, 
to the original as well as to the derived.] 

§ 4. /'//. The nuirk of several ideas combined in one alone 
is the name. 

Th. [That means, if they can be combined, in which respect 
they are often lacking.] 

Ph. The crime of killing an old man, not having a name 
like parricide, is not at first regarded as a complex idea. 

Th. [The reason why the murder of an old man has no name 
is that, the laws not having attached thereto a particular pun- 
ishment, this name would be useless ; but ideas do not depend 
on names. An ethical author who should invent one for the 
crime and treat in a special chapter of Gerontophony, showing 
what is due to old men and how it is a barbarous act not to 
spare them, would not on that account present us with a new 
idea.] 

§ 6. Ph. It is always true that the manners and usages 
of a nation, making combinations familiar to it, cause each, 
language to have particular terms, which cannot always be 
translated word for word. Thus ostracism among the Greeks 
and inoscriptio among the Ilomans were words which other 
languages cannot express by equivalent words. Therefore, 
change of customs makes also new words. 

Th. [Chance also plays its part, for the French do not use 
horses as much as other neighboring peoples ; but having 
abandoned their old word, which corresponded to the cavalcar 
of the Italians, they are forced to say by j^aixqyhrase : aller d 
cheval — to go on horse-back.] 

§ 9. Ph. We acquire ideas of mixed modes by observation, 
as when Ave see two men wrestling ; we acquire them also by 
invention (or a voluntary union of simple ideas), thus, he who 
invented printing had the idea of it before this art existed. 
We acquire them finally by explaining terms, affecting actions 
which Ave liaA^e never seen. 

Th. [We can further acquire them Avhile dreaming or in a 



CH. XXII] ON HUMAN UNDERSTANDING 223 

state of reveiy without the combinations being voluntary, for 
example, when we see in a dream a golden palace without 
having thought of it before.] 

§ 10. Ph. The simple ideas which have been most modified 
are those of thought, motion, and power, whence actions are 
conceived to floAv; for the great business of mankind consists 
in action ; all actions are thoughts or motions. The power or 
aptitude to do anything which is found in man constitutes 
the idea which we call habit, when this power has been 
acquired by often doing the same thing; and when we can 
force it to action upon each occasion that presents itself, we 
call it disposition. Thus, tenderness is a disposition to friend- 
ship or love. 

Th. [By tenderness you understand here, I presume, the 
tender heart, but elsewhere you seem to me to regard tender- 
ness as a quality which one has, as a lover, which renders him 
very sensible to the good and evil of the object loved. This it 
is to which it seems to me the chart of affection is moving in 
the excellent romance Clelie.^ And, as charitable persons love 
their neighbor with some degree of tenderness, they are sensi- 
ble to the good and evil of another, and generally those who 
have the tender heart have some disposition to love with ten- 
derness.] 

Ph. Boldness is the power to do or say before others what 
you wish without being put out of countenance, a self-confi- 
dence, which, in relation to this last j^art which concerns dis- 
course, had a particular name among the Greeks. 

Th. [It would be well to seek a word for this notion, which 
is here attributed to that of boldness, bvit which is often em- 
ployed wholly otherwise, as when we say Charles the Bold. 
Not to be put out of countenance is a strength of mind, but 
one which bad men abuse when they have become impudent; 
as shame is a weakness, but excusable and even praiseworthy 
in certain circumstances. As for parrhesia,^ which you per- 
haps understand by the Greek word, it is still attribiited to 
Avriters who speak the truth without fear, although, then not 

1 Clelie, Histoire Romaine, a romance by Mile. Scudery, 1007-1701. The 
s<'ene is laid early in Roman history ; the heroine is Cloelia, who escaped Irom 
Porsena l)y swimming the Tiber. — Tr. 

2 irapp-qcria. — Tr. 



224 Li:iBM'iy/S nUTIQUK OF LOCKE [hk. 



spoakinjj in the presence of people, they are not liable to be 
ilisi'ountonani'eil.] 

§ 11. Ph. As poH-cr is the source whence proceed all adjo?js, 
tlio name of cause is given to the substances in which these 
powers reside, when they reduce their poiver to act; and they 
call effects the substances produced by this means, or rather 
the simple ideas (i.e. the objects of simple ideas), which, by 
the exercise of power are introduced into a subject. Thus the 
e(ficacij by which a new substance or idea (quality) is pro- 
duced, is called actioji in the subject exercising this power and 
2}assion in the subject in which some simple idea (quality) is 
altered or produced. 

Th. [If poicer is taken as the source of action, it means 
something more than an aptitude or facility, by which power 
was explained in the preceding chapter ; for it includes, be- 
sides, tendency as I have already more than once remarked. 
This is why in this sense I have been wont to appropriate to 
it the term entelechy, which is either primitive and answers to 
the soul taken as an abstract thing, or derivative as it is con- 
ceived in conation (Ze conatus) and in vigor and impetuosity. 
The term cause is here vmderstood only as efficient cause ; but 
it is also understood as Jinal or the motive, not to speak here 
of matter and form which are also called causes in the schools. 
I do not know whether we can say that the same being is 
called action in the agent and passion in the patient, and is 
thus found in two subjects at once like relation, and, whether 
it is not better to say that there are two beings, one in the 
agent, the other in the patient.] 

Ph. Many words which seem to express some action signify 
only the cause and the effect ; as creation and annihilation 
contain no idea of action or of the manner, but simply of the 
cause and the thing Avhich is produced. 

Th. [I admit that in thinking of creation, we do not con- 
ceive a mode of acting, capable of any detail, which cannot 
indeed there be expedient; but, since we express something 
besides God and the world, for we think that God is the cause 
and the world the effect, or else that God has produced the 
Avorld, it is manifest that we think still of action.]^ 

1 Leibnitz regards the concept of creation in the sense of the origination of 
substances as incapable of further explanation because we can form no idea 



CH. xxiii] ON HUMAN UNDERSTANDING 225 

CHAPTER XXIII 

OF OUR COMPLEX IDEAS OF SUBSTANCES 

§ 1. Ph. The mind notices that a certain number of simple 
ideas constantly go together, which, presumed to belong to one 
thing onl}', are called by one name when thus united in one 
subject. Whence it comes that, although this is in truth a 
mass of many ideas joined together, we are afterwards led by 
inadvertence to speak of them as a single, simple idea. 

Tli. [I see nothing in the accepted expressions which de- 
serves to be taxed with inadvertence ; and although we recog- 
nize only one subject and one idea, we do not recognize only 
one simple idea.] 

Ph. ISTot being able to imagine how these simple ideas can 
subsist by themselves, we are accustomed to assume something 
which sustains them (^substratum), in which they subsist or 
whence they result, to which for this effect we give the name 
of substa7ice.~\ 

Th.^ [I believe that there is reason in thus thinking, and 
we have only to accustom ourselves to it or to assume it, since, 
at first, we conceive several predicates in one and the same ' 
subject, and these metaphorical words, s^ipport (soutien) or sub-- ' 
stratum mean only this ; so that I do not see why it should 
cause any difficulty. On the contrary, it is rather the concretum, '■ 
as wise, warm, shining, which arises in our mind, than the 
abstractions or qualities (for these and not the ideas are in 
the substantial object), as knowledge, heat, light, etc., which 
are much more difficult to comprehend. We may even doubt 
whether these accidents are veritable existences, as in fact 
they are very often only relations. We know also that it is 
these abstractions which cause the greatest difficulties to 
spring up when we wish to examine them minutely, as those 

of the process. For some other expressions couceriiiiii;; it, cf. La Moiiado- 
lixjic, § 47, Gerhanlt, (), ()14 ; Erdmauii, 708, h. ; Letter to Bayle, Gerhardt, 3, 
58; Erduiann, 191. Gerhardt, ?■>, (Jl, and note, says the original is without 
date; Erdmann gives it 1702. Cf. also Dillniann, ?'inc ncuc iJarstf/. d. Leib- 
niz. Monadenlehre , p. 4.51 aq. — Tr. 

1 Erdmann has " Ph.," a typographical error. — Tr. 
Q 



2l>(S LKlllMlV/S llJirKiL K OF LOCKE [uic. ii 

know who are familiar with the subtilties of the scholastics, 
the most intricate of which falls at once if we will banish 
abstract existence and resolve to speak ordinarily only by 
concretes and admit no other terms in scientific demonstra- 
tions bnt tliose which represent substantial subjects. Thus it 
is iiodum quaerere in scirpo,^ if I may so speak, and reversing 
things to take the qualities or other abstract terms as the 
easier ;uid the concrete as something very difficult.] 

$ 1'. J'h. We have no other notion at all of pure substance 
in general, than of an indescribable subject, which is to us 
altogether unknown and which is supposed to be the support 
of qualities. We speak like children to one who has no 
sooner asked them what a certain thing unknown to them is, 
than they make this reply very satisfactory to their taste that 
it is something, but, which employed in this way, means that 
they do not know what it is. 

Til. [In distinguishing two things in substance, the attri- 
butes or predicates, and the common subject of these predi- 
cates, it is no wonder that we can conceive nothing particular 
in this subject. It must be so, indeed, since we have already 
separated from it all the attributes in which we could conceive 
any detail. Thus to demand something more in this pure subject 
in general than what is necessary in order to conceive that it 
is the same thing (for example, which understands and wills, 
which imagines and reasons), is to demand the impossible, 
and to act contrary to our own supposition, which has been 
made in making abstraction and conceiving separately the 
subject and its qualities or accidents. We could apply the 
same pretended difiiculty to the notion of being and to all that 
is clearer and more primitive ; for we could demand of the 
philosophers what they conceive when conceiving pure being 
in general; for all detail being excluded by that means there 
will also be little to say, when we are asked what is ^)?<re sub- 
stance in general. Thus I believe that the philosophers do 
not deserve to be laughed at, as is here done, in comparing 
them with an Indian philosopher, who, being asked upon what 
the earth rested, replied, upon a great elephant ; and then 
Avhen asked what sustained the elephant, replied, a great tor- 

1 To seek a knot in a bulrush, to find a difficulty when there is none. Cf. 
Plaut. 3Ie7i. 2, 1, 22 ; Ter. And. 5, 4, 38. —Tr, 



CH. xxiii] ON IIUMxVN UNDERSTANDING 227 

toise ; and, at last, when pressed to say upon what the tortoise 
rested, was compelled to say something, I knoiv not ivhat. But 
this consideration of substance,^ entirely slender as it appears, 
is not so empty and sterile as you think. It gives rise to 
many consequences of greatest importance in philosophy, and 
which are capable of giving it a new aspect.] 

§ 4. Ph. We have no clear idea of substance in general, and 
§ 5, we have as clear an idea of mind as of body; for the 
idea of corporeal substance in matter is as far from our con- 
ceptions as that of spiritual substance. It is almost as the 
promoter said to this young doctor of law, who cried to him 
in the solemnity, to say utriusque : You are right, sir, for you 
know as much in tlie one case as the other. 

Th. [As for myself, I believe that this opinion of our igno- 
rance arises from that which demands a kind of knowledge of 
which the object does not admit. The true mark of a clear 
and distinct notion of an object is the means we have of 
knowing therein many truths by a priori ^ proofs, as I have 
shown in a discourse on truths and ideas,'' published in the 
" Actes de Leipzig " of the year 1684. 

§ 12. Ph. If our senses were sufficiently penetrating, the 
sensible qualities, for example, the yellow color of gold, would 
disappear, and instead of that we should see a certain admir- 
able contexture of parts. This appears evident by means of 
microscopes. This present knowledge is suitable to the state 
in which we find ourselves. A perfect knowledge of things 

1 lu Leibnitz's philosophy substance is a unitary, individual, spontane- 
ously active being, as opposed to the " empty and sterile " conception of Aris- 
totelian scholasticism; cf. ante, p. 15i and note. Locke's criticism concerns 
the scholastic conception only. — Tr. 

2 Cf. Neio Kssuys, Bk. IV., chap. 17, § 1, Th.; Theodicee, I., § 44, Gerhardt, 
6, 127; Erdmann, 515, b. For a brief critical history of the concepts of the 
(/ priori and the a posteriori, cf. Rudolph Eucken, The Fundamental Concepts 
of Modern Philosophic Thought, pp. 81-91, D. Appleton and Co., New York, 
1880 ; and for Leibnitz's use of the terms, op. cit., p. 82, with the note contain- 
ing references to the places where a priori occurs in ErdiiKinn's and Foncher 
de Careil's editions of his works. — Tr. 

3 Meditationes de Cognitione, Veritate et Ideis, in the " Acta Eruditorum," 
Nov., 1G84. Gerhardt, 4, 422 sq. ; Erdmann, 79 sq. The passage referred to 
is found in Gerhardt, 425 ; Erdmann, 80 b. ; translation, Dnucnu, Philos. Works 
of Leibnitz, PiO. The piece has been translated into German, witJi notes, by 
J. H. V. Kirchniann in his Philos. Bihliothek, Bd. 81, Bic klein. philos. ivicht, 
Schriften v. G. W. Leibniz ; Bd. 82, Erlauternngen. — Tr. 



'2-2S LKllJNllZS CKri'lQL'K OF LUCKE [bk. 



which surrouud us, is, perhaps, beyond the capacity of every 
tiuite being. Our faculties suffice to make us know the Crea- 
tor, and to instruct us as to our duties. Should our senses 
bocome more acute, such change would be incompatible with 
our nature. 

Th. [All that is true; and I have said something to the 
same effect above. But the color yellow does not cease to 
be a reality like the rainbow, and we are apparently destined 
to a state far beyond the present, and can even go on to the 
intinito, for there are no elements in the corporeal nature. If 
there were atoms, as the author appeared to believe in another 
place, perfect knowledge of the body could not be beyond 
every finite being. For the rest, if some colors or qualities 
should disappear from our eyes better armed or become more 
penetrating, others would apparently spring into being, and 
it would require a new growth of our perspicacity to make 
these also disappear, and this could go on to infinity, as the 
actual division of matter effectively proceeds.] 

§ 13. Ph. I do not know but that one of the great advan- 
tages which some spirits have over us consists in the fact that 
they can assume to themselves organs of sensation which are 
precisely suited to their present design. 

Th. [We do this indeed in making for ourselves micro- 
scopes ; but other creatures can go much farther. And, if we 
could transform our eyes themselves, which we do effectively 
to some extent according as we wish to see near at hand or at 
a distance, we should be obliged to have something^ belonging 
more exclusively to us than they in order to shape them by 
its means, for it is necessary, at least, that all be done mechan- 
ically, because the mind cannot operate immediately upon the 
body. For the rest, I am also of the opinion that genii per- 
ceive things in a manner which is somewhat related to ours, 
even if they should have the agreeable advantage which the 
imaginative Cyrano- attributes to some animated natures in 

1 I.e. the soul to make use of the capacity of the eyes for accommodation. 
— Tr. 

2 Cyrano de Bergerac, c. 1620 — 1655, in his philosophical romance, Ilistoire 
comique des etats et empires du soleil. He was author also of the Histoire 
comique des etats et empires de la lune, or, as the title is sometimes given, 
Voyage dans la lune. — Tr. 



cii. xxiii] ON HUMAN UNDERSTANDING 229 

the sun, composed of an infinite number of little winged crea- 
tures, which, by transporting themselves according to the 
command of the ruling soul, form all kinds of bodies. There 
is nothing so marvellous that the mechanism of nature cannot 
produce it; and I believe that the learned fathers of the 
Church were right in attributing bodies to the angels.^] 

§ 15. Ph. The ideas of thinking and of moving a body, 
which we find in that of the mind, can be conceived as clearly 
and distinctly as those of extension, solidity, and mobility, 
which we find in matter. 

Th. [As regards the idea of thought I agree. But I am 
not of this opinion as regards the idea of moving bodies, for, 
according to my system of Pre-established Harmony, bodies 
are so made that being once put in motion, they continue 
therein, according as the actions of the mind require. This 
hypothesis is intelligible ; the other is not.] 

Ph. Each act of sensation gives us an equal view of things 
corporeal and spiritual ; for while sight and hearing give me 
the knowledge that there is some corporeal being without me, 
I know in a way still more certain that there is within me a 
spiritual being which sees and hears. 

Th. [It is very well said and very true that the existence 
of the spirit is more certain than that of sensible objects.-] 

§19. Ph. Spirits as well as bodies can operate only where 
they are and in different times and places ; thus I can only 
attribute change of place to all finite spirits. 

Th. [I believe that is reasonable, place being only an order 
of coexistences.] 

Ph. It is only necessary to reflect upon the separation of 
the soul and the body by death to be convinced of the move- 
ment of the soul. 

Th. [The soul might cease to operate in this visible body ; 
and if it could cease thinking all at once, as the author has 
maintained above, it might be separated from the body with- 
out being united to another; thus its separation would be 
without movement. But for myself, I believe that it thinks 

1 Cf. Letters to Des Bosses, Sept. 20, Oct. 4, 1706, Gerhardt, 2, 316, 319; 
Erdmanii, 439. Also Descartes' letters, passim. — Tr. 

2 Cf. Descartes, Meditations, especially II. aud VI. Veitch's trauslation, 
8t]i ed", pp. 104 sq.. 151 sq. — Tr. 



o;;o 1,1:1 bnh'zs currKiric of locke [hk. u 

iind feels always, that it is always united to some body, and, 
indeed, that it never leaves entirely and all at once the body 
to wliii'h it is united.] 

{} L'l. Ph. If anyone says that si)irits are not in loco sed in 
ali(jiio ubi I do not suppose that now we would rely much 
upon this method of speaking. But if anyone thinks that 
it can receive a reasonable sense, I pray him to express it in 
langnage generally intelligible, and to draw therefrom after- 
wards a reason showing that spirits are not capable of motion. 

Th. [The schools have three kinds of JJheity, or modes of 
existing somewhere. The first is called circumscriptive, which 
they attribute to bodies in space which are there jnmctatim, in 
such wise that they are measures according to which we can 
assign the points of the thing placed corresponding to the 
points of space. The second is the definitive, when we can 
define, i.e. determine, that the situated thing is in such a space, 
Avithout being able to assign the precise points or the peculiar 
places exclusive of what is there. Thus it has been con- 
sidered that the soul is in the body, not supposing it possible 
to assign a precise point at which the soul or some portion of 
the soul is, without its being also at some other point. More- 
over, many learned men have thus viewed the matter. It is 
true that Descartes desired to place narrower limits to the 
soul by locating it properly in the pineal gland. ^ iSTeverthe- 
less he did not dare to say that it is exclusively at a certain 
point in this gland ; and this not being so he gains nothing, 
and it is in this respect precisely as if he gave it the entire 
body as its prison or place. I believe that nearly the same 
statement as that made regarding souls, must be made in 
respect to the angels, whom the great doctor, a native of 
Aquino, believed to be in a place only by operation ^ which in 
my view is not immediate and reduces itself to pre-established 
harmony. The third ubeity is the repletive, which is attrib- 
uted to God, who fills all the universe in a still more eminent 
degree than the disembodied spirits, for he works immediately 

1 Cf. Descartes, Biojytrica, IV., 1 sq.; Passioncs Animas, I., 31 sq.; also 
Prin. Philos., IV., 189, 19fi, 197, altlioiigli here the point of contact in the 
brain of the soul and hody is not designated by name. — Tr. 

2 Cf. Thomas Aquinas, 1225 or 1227-1274, Summa Theologica, Pt. I. Quest. 
52, Article, 2; also Quest. 53. — Tr. 



cir. xxiii] ON HUMAN UNDERSTANDING 231 

upon all creatures by continually producing them, while finite 
spirits cannot exercise any ininiediate influence or operation. 
I do not know whether this doctrine of the schools deserves 
to be ridiculed, as it seems some try to do. But we can 
always attribute a kind of movement to souls at least in rela- 
tion to the bodies with which they are united, or in relation 
to their mode of perception.] 

§ 23. Ph. If any one says he knows not how he thinks, I 
reply that he knows no more how the solid particles of the 
body are united to make an extended whole. 

Th. [It is difficult enough to explain cohesion; but this 
cohesion of parts does not appear necessary to make an 
extended whole, since we can say that matter perfectly subtile 
and fluid constitutes an extension, without the particles being 
united the one to the other. But, to speak the truth, I 
believe that perfect fluidity belongs only to the prhnary 
matter,^ i.e. matter in the abstract, and, as an original quality, 
just as repose ; but not to secondary matter, such as is 
actually found, invested with its derivative qualities ; for, I 
believe that there is no mass, which is of the utmost subtil- 
ity ; and that there is more or less connection everywhere, 
which arises from movements so far as they are conspirant 
and would be disturbed by separation, which cannot take 
place without some violence and resistance. For the rest, the 
nature of perception and thus of thought furnishes a notion 
of the most original conditions. I believe, further, that the 
doctrine of substantial unities or monads will throw much 
light upon it.] 

Ph. As for cohesion, many explain it by means of the sur- 
faces by which two bodies touch, which an ambient fluid ^ (for 
example, the air) presses one against another. It is very 
true that the pressure § 24 of an ambient fluid can hinder the 
avulsion of two polished surfaces from one another in a line 
perpendicular to them ; but it cannot hinder them from separat- 
ing by a movement parallel to tliese surfaces. This is why, 
if there were no other cause of the cohesion of bodies, it 
would be easy to separate all their parts, by making them thus 

1 Cf. ante, p. 131 and note. — Tr. 

2 Locke's term, Philos. Works, Vol. 1, p. 438, § 21 (Bolm's ed.). — Tr. 



:.'.".:> LElliNITZ'S CKiriQUE OF LOCKE [bk. a 

slide latorally, taking therefor any ])lane you wish wliich 
intersects any mass of matter. 

Th. [Ves, no doubt if all the smooth particles applied to 
each other were in one and the same plane or in parallel 
planes; but that not being so nor capable of so being, it is 
manifest that in trying to make the one slide, you Avill act 
altogether differently upon an infinite number of others, whose 
plane will make an angle with the first ; for you must know 
that it is difficult to separate two congruent surfaces, not only 
when the direction of the movement of separation is perpen- 
dicular, but fui-ther when it is oblique to the surfaces. Thus 
it may be conceived that there are leaves applied to one 
another in every direction in the polyhedral bodies that nature 
forms in ores and elsewhere. But I admit that the pressure 
of the ambient fluid \ipon smooth surfaces applied to each 
other does not suffice to exj^lain the basis of all cohesion, for 
it is tacitly assumed that the tables applied the one against 
the other already have cohesion.] 

§ 27. Ph. I have always supposed that the extension of a 
body was something else than the cohesion of solid particles. 

Th. [That does not appear to me to agree with your o^^ti 
preceding explanations. It seems to me that a body in which 
there are internal movements or whose particles are in the act 
of detaching themselves one from another (as I believe hap- 
pens always) cannot be extended. Thus the notion of exten- 
sion ai)pears to me wholly different from that of cohesion.] 

§ 28. Ph. Another idea we have of body is the 2>oice7- of 
communicating 'motion by imjndse; and another we have of the 
soul is the poiver of 2'>t'oducing motion hy thought. Experience 
clearly fiu-nishes us each day these two ideas ; but if we wish 
to investigate further how this is done, we find ourselves 
equally in the dark. For, as regards the communication of 
motion, wherein one body loses as much motion as another 
receives, which is the most ordinary case, we conceive there 
nothing else than a motion which passes from one body into 
another; which is, I think, as obscure and as inconceivable 
as the manner in which our mind moves or stops our bodies by 
thouglit. It is still more difficult to explain the increase of 
motion by means of impulse, which is observed or believed to 
happen in certain cases. 



CH. xxiii] ON HUMAN UNDERSTANDING 233 

Th. [I am not astonished that yon find insurmountable dif- 
ficulties where you seem to assume a thing so inconceivable 
as the passage of an accident from one subject to another ; 
but I see nothing which compels us to an assumption which is 
no less strange than that of the scholastics of accidents with- 
out a subject, which they have taken care however to attribute 
only to the miraculous action of the divine omnipotence, 
while here this passage would be merely an ordinary one. I 
have already said something about it above (chap. 21, § 4^), 
where I also remarked that it is not true that a body loBes as 
much motion as it gives to another ; which they seem to conceive 
as if motion were a substantial thing and resembled salt dissolved 
in water, which comparison is actually the one M. Eohaut,^ if 
I mistake not, has used. I add here that this is not even the 
most usual case, for I have elsewhere demonstrated that the 
same quantity of motion is maintained only when the two 
bodies which come into collision proceed in one and the same 
direction before the collision and still proceed in one and the 
same direction after the collision. It is true that the veritable 
laws of motion are derived from a cause superior to matter. 
As for tJie power of producing motion by thought, I do not think 
we have any idea of it, as we have no experience of it. The 
Cartesians themselves admit that souls cannot give a new 
force to matter, but they pretend that they give it a new 
determination or direction of the force it has already. For 
myself, I maintain that souls change nothing in the force nor 
in the direction of bodies ; that the one would be as incon- 
ceivable and unreasonable as the other, and that you must 
avail yourself of the pre-established harmony in order to 
ex])lain the union of the soul and the body.] 

Ph. It is worth our consideration whether active power is 
not the proper attribute of spirits and passive power of 
bodies ? Whence we might conjecture that created spirits, 

1 Cf. ante, p. 176. — Tr. 

2 James Roliaut or Rohault, 1620-1675, a French physicist, a follower of 
Descartes. His chief work, the Physics, was written in Frencli, and trans- 
lated into Latin, with valuable notes, hy Dr. Samuel Clarke, 11)75-1729, and 
into English by his brother Dr. John Clarke. It was a text-book in the Uni- 
versity of Cambridge, until supplanted by the treatises of Sir Isaac Newton. 
The original work first appeared in 1071, and enlarged, in two vols., in 1682. 
Clarke's Latin version, 8vo., in 1097; the 4th and best edition, Jacobi Rohaulti 
Physica, 8vo., 1718. —Tr. 



234 LEIBNITZ'S CUITIQUE OF LOCKE [bk. ii 



Wm'j; ai'tivo and passive, are not totally separate from simply 
passrve matter ; and that these other beings, which are active 
and passive at the same time, partake of Ijoth. 

Th. [These thoughts greatly please me and entirely express 
my conviction, provided you explain the word spirit so gener- 
ally that it comprises all souls, or rather (to speak still more 
generally) all the entelechies or substantial -unities, which are 
analogous to spirits.] 

§ oi. Fh. I much wish that you woiiLd show me in the 
notion we have of spirit anything more confused ' or nearer a 
contradiction than what the very notion of body includes. I 
mean inhnite divisibility. 

Th. [What you here say further in order to make evident 
tliat we understand the nature of the spirit as well or better 
than that of the body is very true ; and Fromondus,- who has 
published a book, De compositione continui, was right in enti- 
tling it Labyrinth. But the question arises from a false idea 
you have of the nature of body as well as of space.] 

§ 33. Ph. The idea of God indeed comes to us as others 
do, the complex idea of God we have being composed of the 
simple ideas which we receive from reflection and which we 
extend by the idea we have of the infinite. 

Th. [Upon that question I refer to what I have already 
said in several places in order to make evident that all these 
ideas, and particularly that of God, are in us originally, and 
that we only make ourselves take notice of them, and that 
above all, the idea of the infinite is not formed by an extension 
of finite ideas.^] 

§ 37. Ph. The majority of the simple ideas Avhieh compose 
our complex ideas of substances are, properly considered, only 
fiowers, whatever our inclination to take them as positive quali- 
ties. 

1 Locke's word is "perplexed," Philos. Works, Vol. 1, p. 443 (Bolm's ed.). 
— Tr. 

2 Libert Froidmont or Fromont — Latin, Fromondus — 1587-1653, a Flemish 
theologian, Professor of Philosophy and Theology in the University of Lou- 
vain. His theological, philological, and scientific knowledge was very exten- 
sive. Descartes esteemed highly both his knowledge and his person. Cf. 
Descartes' letters. His book, Lahyrinthus sive de compositione continui, ap- 
peared at Antwerp in 1631. — Tr. 

8 Cf.ante, pp. 16,17; JVeio Essays, Book H., chap. 14, § 27, Th., and note 1, 
ante, p. 158; chap. 17, § 1, Th., ante, p. 162. — Tr. 



cii. XXV] ON HUMAN UNDERSTANDING 235 

Th. [I think that the iwwers, which are not essential to 
substance and which include not only an cqUitade, but also a 
certain tendency, are properly what is or ought to be under- 
stood by reed qualities.'] 



CHAPTER XXIV 

OF COLLECTIVE IDEAS OF SUBSTANCES 

§ 1. Ph. After simple substances we come to the aggregates. 
Is it not true that the idea of this mass of men composing an 
army, is as much a single idea as that of one man? 

Th. [You are right in saying tliat this aggregate {ens per 
aggregationem, to use the language of the school), makes one 
single idea, although, properly speaking, this mass of sub- 
stances does not form in truth one substance. This is a result 
to wliich the soul by its perception and its thought gives its 
last achievement of unity. You may, however, say in a sense 
that it is something substantial, i.e. comprising substances.] 



CHAl'TER XXV 

OF KELATION 

§ 1. Ph. It remains to consider the ideas of relations which 
are the poorest in reality. When the mind regards one thing 
in com})arison with another, this is a relation or respect,^ and 
the denominations or relative terms, which are produced, are 
like so many marks which serve to lead our thoughts beyond 
the subject to something distinct from it, and these two are 
called subjects of the relation (relata). '~^ 

Th. [Relations and orders have something of the essence of 
reason, although they have their foundation in tilings ; for we 
can say that tlieir reality, like that of eternal truths and possi- 
bilities, comes from the supreme reason.] -_j 

§ 5. Ph. There may, however, be a change of relation witli- 
out any change happening in the subject. Titius, whom to- 

1 Locke's word, Philos. Wurkx, Vol. 1, p. ii'J (Bohu's cd.).— Tu. 



'2M LKinXlTZ'S CRITIQUE OF LOCKE [nic. ii 

(lay I consider as a father, ceases to be such to-morrow without 
any chaiii,'e being made iu liimself, by the sole fact of his 
son's (h'ath. 

Th. [Tliat statement may very well be made in view of 
things which are perceived; although in metaphysical strict- 
ness it is true that there is no entirely exterior denomination 
(deuomiiuUio pure extrinseca) because of the real connection of 
all things.] 

§ (5. Ph. [I think that relation is only between two things.] 

Til. [There are, however, examples of relation between sev- 
eral things at once, as that of order or that of a genealogical 
tree, which expresses the rank and connection of all the terms 
or members, and even a figure like that of a polygon includes 
the relation of all the sides.] 

§ 8. Fh. It is well to consider also that the ideas of rela- 
tions are often clearer than those of the things Avhich are the 
subjects of the relation. Thus the relation of father is clearer 
than that of man. 

Th. [That is because this relation is so general that it may 
also suit other substances. Moreover, as a subject may have 
clearness and obscurity, the relation might be grounded in the 
clear. But if the form itself of the relation involved the 
knowledge of that which is obscure in the subject, it would 
participate in this obscurity.] 

§ 10. Ph. The terms \vhich.necessarUy lead the mind to other 
ideas than those which are supposed really to exist in the 
thing to which the term or word is applied are relative ; the 
others are absolute. 

Th. [You have well added this " necessarily" and you might 
add " expressly " or " at first," for you can think of black, for 
example, without thinking of its cause ; but it is by remaining 
within the limits of a knowledge which presents itself at first 
and which is confused or very distinct, but incomplete ; the 
one when there is no resolution of the idea, the other when 
you limit it. Otherwise there is no term so absolute or so 
loose as not to include relations and the perfect analysis of 
which does not lead to other things and even to all others ; so 
that you can say that relative terms indicate expressly the rela- 
tion they contain. I here oppose the absolute to the relative, 
and it is in another sense that I have opposed it above to the 
limited.'^ 



CH. xxvi] ON HUMAN UNDERSTANDING 237 

CHArTER XXVI 

OB^ CAUSE AND EFFECT AND SOME OTHER RELATIONS 

§§ 1, 2. Ph. Cause is that which produces a simple or in- 
complex idea ; effect is that which is produced. 

Th. [I see, sir, that you often understand by idea the objec- 
tive reality of the idea or the quality which it represents. You 
define only efficient cause, as I have already remarked above. 
You must admit that, in saying that efficient cause is that 
which produces and effect that which is produced, you make 
use only of synonyms. It is true that I have heard you say a 
little more distinctly, that ccmse is that which makes another 
thing commence to exist, though this word "makes'' passes 
over also the principal difficulty entirely. But that will be 
explained better elsewhere.] 

Ph. In order further to touch some other relations, I remark 
that there are terms employed to designate time which are 
ordinarily regarded as signifying only positive ideas, which 
are nevertheless relative, as young, old, etc., for they involve a 
relation to the ordinary duration of the substance to which 
you attribute them. Thus a man is called young at the age of 
twenty years, and very young at the age of seven years. But 
we call a horse old at twenty years, and a dog at seven. But 
we do not say that the sun and the stars, a ruby or a diamond, 
is young or old, because we do not know the ordinary periods 
of their duration. § 5. The same is true regarding place or 
extension, as when a thing is said to be high or loiv, great or 
small. Thus a horse which will be large according to the idea 
of a Welshman, appears very small to a Fleming ; each thinks 
of the horses which are raised in his country. 

Th. [These remarks are very good. It is true we some- 
times SAverve a little from this sense, as when we say that a 
thing is old when comparing it not with those of its kind, but 
Avith other kinds. For example, we say that the world or the 
sun is very old. Some one asked Galileo if he believed that 
the sun was eternal. He replied : eterno nd ma ben a)dico — 
eternal, no, but very ancient. 



o;Js Li:iliMT//S CKiniiUK OF LOCKE Lbk. ii 

CHAPTER XXVII 

WHAT TDKXTITV OK DIVERSITY IS 

§ 1. /'//. A relative idea of the greatest importance is that 
of kh'utitif or diversity. We never find and we cannot conceive 
it possible that two tilings of the same kind exist in the same 
time in the same place. Therefore when we ask ichether a 
thing is the same or not, the question always relates to a thing 
which at such a time exists in such a place ; whence it follows 
that a thing cannot have two beginnings of existence, nor two 
things one beginning only in relation to the time and the 
place. 

TJi. [It is always necessary that besides the difference of 
time and place there be an internal jninciple of distinction, and, 
though there are many things of the same kind, it is never- 
theless true that none of them are ever perfectly alike : thus 
although time and place (i.e. external relation) serve us in 
distinguishing things which we do not easily distinguish by 
themselves, the things do not cease to be distinguishable in 
themselves. The essence {le precis) of identity and diversity 
consists, then, not in time and place, although it is true that 
the diversity of things is accompanied by that of time or of 
place, because they bring with them different impressions of 
the thing ; not to say that it is rather by the things that one 
place or one time must be distinguished from another, for in 
themselves they are perfectly alike, but they are not, there- 
fore, substances or complete realities. The mode of distin- 
guishing which you seem to propose here, as unique in things 
of the same kind, is based upon the supposition that penetra- 
tion is not conformable to nature. This supposition is reason- 
able, but experience indeed makes it evident that it is not 
closely applied here, when the question concerns distinction. 
We see, for example, two shadows or rays of light which in- 
terpenetrate, and we might invent for ourselves an imaginaiy 
world wherein bodies would act in the same way. But we do 
not cease to distinguish one ray from another by the very 
rate of their passage even when they cross each other.] 



CH. xxvii] ON HUMAN UNDEESTANDING 239 

§ 3. Ph. What is called the principle of individuation {prin- 
cipium individiiatioms) in the schools, where they torment 
themselves so much to know what it is, consists in existence 
itself which determines each being to a particular time and 
place incommunicable to two beings of the same kind. 

Th. The 2yrincipJe of individuation ' reappears in individuals 
in the principle of distinction of which I just spoke. If two 
individuals were perfectly alike and equal and (in a word) 
indistinguishable in themselves, there would be no principle 
of individuation ; and I even venture to assert that there 
would be no individual distinction or different individuals 
under this condition. This is Avhy the notion of atoms is 
chimerical, and arises only from the incomplete conceptions 
of men. For if there were atoms, i.e. bodies perfectly hard 
and perfectly unalterable or incapable of internal change and 
capable of differing among themselves only in size and shape, ' 
it is plain that in the possibility of their being of the same 
shape and size they would then be indistinguishable in them- ' ' 
selves, and could be distinguished only by means of external 
denominations without an internal basis, which is contrary to 
the highest principles of reason. But the truth is that every 
body is alterable, and indeed actually changes so that it differs 
in itself from every other. I remember that a distinguished • 
princess,^ wdio is of a pre-eminently excellent mind, said one 

1 Leibnitz discussed this principle in his disputation for the degree of 
Bachelor of Philosophy, entitled, Disputatio metapliysica de privcipio indi- 
vidui, which in his sixteenth year he publicly defended at Leipzij;-, IMarch 30, 
1(563; cf. Guhrauer, Leibniz. Leben, 1, 27 .^q. This piece is found in Gcrliardt, 
4, 15-26, where the title-page gives the date of the public defence, May 30, 
1663; Erdmanu, 1-5; it has also been edited, with an extended critical intro- 
duction, from a copy found in the Library at Hannover by Dr. G. E. Guhrauer, 
and published at Berlin in 1837. J. H. von Kirclnnanu has published a German 
translation with elaborate and extensive notes in his Philos. Bihliothek, Bd. 
81, Die Jdeiii. pjhilos. ivieht, ScTiriften G. W. Leilmix ; Bd. 82, IJrliiutervnfjen. 
For a recent discussion of the principle of individuality, cf. R. Eucken, The 
Fundamental Concepts of Mod. Philos. Thow/ht, pp. 231-248. New York, 
1880. — Tr. 

2 Sophie Charlotte, 1668-1705, the first Queen of Prussia, the friend and in 
a certain sense the pupil of Leil)nitz in philosophy. The Tli.eodicee originated 
in his philosophical conversations with her. Cf. Gerhardt, 6, 3'.); Erdmanu, 
474 b. Leibnitz's correspondence with her is found in (). Klopp, Die Werke 
von Leibniz, Yo]. 10, Hannover, 1877; the letters of philosopliical importance 
in Gerhardt, .3, 343 sq. ; (>, 488 .sq. ■ 7, 544 ; tlie letter in (x. 6, 4'.)',) sq. is translated 
in Duncan, Philos. Works of Leibnitz, 14!) sq. Cf. also Kuuo Fischer, Uesch. 
d. n. Philos., Vol. 2, p. 261 sq., 3d ed., 1889. —Tii." 



210 I.KinNITZ'S ClUTIQUE OF LOCKE [bk.it 

(lay whilo walking in her garden that she did not believe 
there were two h-aves perfeetly alike. A gentleman of dis- 
tinction, who was walking with her, thought he would easily 
iind some. But although he searched long, he was convinced 
hy his eyes that he could always note the difference. We see 
by these considerations, hitherto neglected, how far we have 
wandered in philosophy from the most natural notions, and 
how far W(> have departed from the great principles of true 
metaphysic] 

§ 4. Ph. That which constitutes the unity (identity) of one 
and the same plant is the possession of such an organization 
of parts in a single body, as participates in a common life 
which endures while the plant subsists, although the parts 
change. 

Th. [The organization or configuration Avithout an existing 
principle of life, which I call a monad, would not suffice to 
cause the continuance of idem nuviero or the same individual ; 
for the configuration can abide specifically Avithout abiding ^ 
individually. When a horseshoe is changed into copper in a 
mineral spring of Hungary, the same figure in kind remains, 
but not the same as cm individual ; for the iron is dissolved, 
and the copper, Avith Avhich the water is impregnated, is pre- 
cipitated and insensibly takes its place. N"ow figure is an 
accident Avhich does not pass from one subject to another (de 
sicbjedo in subjection). So we must say that bodies as well 
organized as others do not remain the same in appearance, 
and, speaking strictly, not at all. It is almost like a river 
Avhich ahvays changes its Avater, or like the ship of Theseus 
which the Athenians Avere ahvays repairing.- But as regards 

J Erdmanu and Jacques omit "siiecifiquement, sans demeurer," the reading 
of Gerhardt. — Tr. 

2 Cy. Plato, PhsBclo. 58 A; Xenophou, Memorabilia, 4, 8, 2. The sacred 
slup, sent yearly to Delos hy the Athenians in consequence of a vow made to 
Apollo hy Theseus when on his way to Crete with the seven youths and seven 
maidens, the annual tribute of the Athenians to the Minotaur, that if rescued 
he would send annually to Delos a ship with gifts and sacrifices as a thank- 
offering for their deliverance, was repaired piece hy piece as necessary, so 
that in form and appearance it remained the same old ship in which Theseus 
himself sailed, while its substance continually changed. The vessel served 
the philosophers as an instance in discussions concerning identity and what 
constitutes it, and as an illustration of a numerical substance continuously 
the same, though constantly changing by the decay and rejection of old and 
the growth and acquisition of new parts, as in the case of the living body. 
— Tk. 



CH. xxvii] ON HUMAN UNDERSTANDING 241 

substances, which are in themselves a true and real substantial 
unity, to which may belong actions properly called vital, and 
as regards substantial beings, qam uao spiritu continentur, iu 
the words of an ancient ■ jurisconsult,^ i.e. which a certain' 
indivisible spirit animates, you are right iu saying that they 
remain perfectly the same individual through this soul or this 
spirit which constitutes the ego in thinking beings.] 

§ 5. Ph. The case is not very different in animals and in 
plants. 

Th. [If vegetables and animals have no soul, their identity 
is only apparent ; but if they have, individual identity is in , 
truth strictly speaking there, although their organized bodies 
do not preserve it.] 

§ 6. Ph. This also shows wherein the identity of the same 
man consists, viz. in the fact alone that he enjoys the same 
life, continued by particles of matter which are in a perpetual 
flux, but which in this succession are vitally united with the 
same organized body. 

Th. [That may be understood in my sense. In fact, the 
organized body is not the same from one moment to another ; 
it is only equivalent. And if it were not related to the soul, 
there would no longer be the same life or vital union. Thus 
this identity would be only apparent.] 

Ph. Whoever shall connect the identity of man with any- 
thing else than a well-organized body, in a certain instant, and 
which thence continues in this vital organization by a succes- 
sion of different particles of matter which are united to it, 
will have difficulty in making an embryo, a man of years, a 
fool, and a wise man the same man, unless it follows from this 
supposition that it is possible for Seth, Ismael, Socrates, Pilate, 
St. Augustine ^ to be one and the same man, . . . and this would 
agree still worse with the notions of those philosophers who 
recognize transmigration and believe that men's souls can be 
sent for punishment of their irregularities into the bodies of 
animals ; for I do not believe that any one who was assured 
that the soul of Heliogabalus existed iu a hog would mean 
that this hog was a man, and the same man as Heliogabalus. 

1 Sextus Pomponius, died 1.'58 A.d. The phrase occurs in the Di,i,'est, 41, 3, 
30, Vol. 2, p. 522, ed. TJi. Mommsen, Berlin: Weidmaiin, 1870. — Tk. 

2 Locke has " St. Austin," Fliilos. Works, Vol. 1, p. 4(J3 (Bohn's ed.). — Tii. 

R 



..J2 LHIBM rZ'S CMMTKiUK OF LOCKE [mc. ii 



Th. [There is liere a question of name and of thing. As for 
the thing, tlie identity of one and tlie same individual sub- 
stance cau be maintained only by the conservation of the same 
•soul, for the body is in a continual Hux, and the soul does not 
dwell in certain atoms appropriated to itself, nor in a little 
incorruptible {indomptable) bone, such as the Liiz'^ of the 
Kabbis. ^loreover there is no transmigration by which the 
soul wholly leaves its body and passes into another. It keeps 
always, even in death, an organized body, a part of the pre- 
ceding, although what it keeps is always subject to insensible 
dissipation and to reparation, and indeed to undergoing in a 
certain time a great change. Thus instead of a trans migra- 
,.tion of the soul there is a transformation, envelopment, or 
•development, and finally a fluxion of the body of this soul. 
A'an Helmont,- the son, thought that souls pass from body to 
body, but always within their kind, so that there will always 
be the same number of souls of one and the same kind, and 
consequently the same number of men and of wolves, and that 
the wolves if diminished or extirpated in England would be 
proportionally increased elsewhere. Certain meditations pub- 

1 The bone which the Jews regarded as incapable of decay, remaining until 
the hist day and forming the nucleus of the resurrection body. Schaarschmidt 
says: " According to the opinion of the Rabbis, says Ulrich in his note to this 
place, the body which we are to receive at the resurrection is already at hand 
iu our backbone. This body or bone, VO {Laz), as it is properly called, they 
held for this reason to be incorruptible. In the Jalkut chadasch, Fol. 142, 
title Mafichiarh, n. 44, the following account is given of it : This Ijone decays 
not, and the lioly giving God will make it soft with the dew, and out of it will 
build the body. The reason why this little bone is not to be exposed to cor- 
rnption, they ijlace in the fact that it has not enjoyed the pleasures of this 
world, as the rest of the members. This doctrine is with them no empty 
.speculation. The old Rabbis of blessed memory have not only seen this boue, 
but have found it actually so strong and hard that their hammer and rock 
flew iu pieces before this little bone was injured iu the least. See Axkafh 
Jiiiclirl in the 4th part," etc. — Tr. 

- Francois Mercure van Helmont, 1()18-1(598, a particTilar friend of the 
Countess of Connaway, in whose Opusriila philosophica, Bk. I., chap. 6, §§ 7, 
8, and cliap. 7, § 4, London, KJDO, this view of his is found in detail. On 
Leibnitz's relations with Van Helmont, cf. Stein, Leibniz and Spinoza, pp. 
'2Wnq., and the refereuces in Stein's notes; also Beil<(f/en, XV., XVI., op. cit. 
pp. o2!)-3:J7. Leibnitz composed for him, at the request of his cousin, the 
Baroness of Merode, a Latin epitaph; cf. Burckhard, Historia Bihlioth. Aii- 
r/ustx, II., p. 320; also Stein, op. cit. pp. 33(5-337. Leibnitz treats of him and 
his doctrine iu his Miscellanies, cf. Otium Uanoveranum, ed. J. F. Feller, 
pp. 226-230, Lipsiaj, 1718. — Tr. 



CH. xxviij ON HUMAN UNDEESTANDING 243 

lished in France would also seem to tend in that direction. If 
transmigration is not taken strictly, i.e. if any one thought 
that souls dwelling in the same subtile body change only from 
a coarser body, it would be possible, even to the passage of 
the same soul into a body of a different kind after the fashion 
of the Brahmins and Pythagoreans. But all that is possible 
is not for that reason conformed to the order of things. But 
the question whether, in case such a transmigration were true, 
Cain, Ham, and Ismael, supposing, according to the Rabbis, 
they were the same soul, would deserve to be called the same 
man, is only one of name ; and I have observed that the cele- 
brated author, whose opinions you have maintained, recognizes 
and explains it very well (wi the last j^aragrwpli of this chapter). 
The identity of substance would occur therein, but in case 
there were no connection of memory between the different 
persons, as the same soul would make, there would not be 
sufficient moral identity to say that it would be one and the 
same person. And if God willed that the human soul should 
go into the body of a hog, forgetting the man and performing 
no rational acts, it would not constitute a man. But if in the 
body of the animal it had the thoughts of a man, and even of 
the man whom it animated before the change, like the Golden 
Ass of Apuleius, one would perhaps have no difficulty in say- 
ing that the same Lucius, who had come into Thessaly to see 
his friends, lived under the ass's hide, where Photis had put 
him in spite of herself, and wandered from master to master 
until the roses he ate restored him to his natural form.^ 

1 Cf. Apuleius, Metamorph., Bk. III., Vol. 1, pp. 229 sq. ■ Bk. XL, pp. 770 sq., 
edition in 6 vols., paging continuous, A. J. Valpy, Loudon, 1825. The Meta- 
morphoses is in contents very similar to a work entitled, Aoiixto? ij oro; (Lucius 
or Ass), ascribed to Lucian, a contemporary of Apuleius who flourished about 
160 A.D., and is most probably an imitation of it. The incidents and adven- 
tures in both are nearly identical, the names only being changed, both writers, 
however, calling the hero Lucius. In the course of his adventures Lucius 
became involved in a love-affair with a waiting-woman by the name of Fotis, 
whose mistress practised tlie art of magic, and changed at will herself and 
others into various animals by the use of certain ointments. Lucius, very 
desirous to learn all about this wonderful art, finally persuaded Fotis, who 
claimed that she understood her mistress's art, to try it on him. She did so, 
intending to change him into an owl, into which form her mistress in the 
sight of them both had just changed herself, but in her haste and confusion 
using the wrong ointment, she changed him, "in spite of herscslf," into an ass. 
The work of Apuleius is much more extcndtid tlian that of I^ician, and, in 



-11 LiaiiMTZ'S CKlTiQLK OF LuCKE [niv. ii 



§ '.►. I'h. I think we can boldly advance the idea that who- 
ever of us saw a creature made and formed like himself, 
although it had never exhibited more reason than a cat or a 
parrot, would not cease to call it a man ; or if he heard a 
parrot discoursing rationally and in a philosophical manner 
would call or think it only a parrot, and would say of the 
former of these animals that it is an uncultivated man, dull 
and destitute of reason, and of the latter that it is a parrot full 
of intelligence and good sense. 

Th. [I should be more of the same opinion upon the second 
point than upon the first, although there is still something to 
be said thereupon. Few theologians would be venturesome 
enough to agree at once and absolutely to the baptism of an 
animal in human form, but without appearance of reason, if 
he were taken while young in the woods and some priest of 
the Roman church should perhaps say conditionally, if you 
are a man I bajjtize you; for they would not know whether 
he is of the human race and whether a rational soul dwells 
therein, and this might be an ourang-outang, an ape externally 
very like a man, such as that one whom Tulpius ^ speaks of as 
having seen, and that one an account of whose anatomy a 
learned physician has published. It is certain (I admit) that 
man can become as stupid as an ourang-outang, but the interior 
of a rational soul would abide there in spite of the^uapansion 
of the exercise of reason as I have explained above ; thus it is 
a point of which we cannot judge by appearances. As for the 
second case, nothing prevents there being rational animals of 
a different kind from ourselves, as those inhabitants of the 
poetic kingdom of the birds in the sun, where a parrot having 
come from this world after its death, saved the life of a trav- 
eller who had treated him well here below. But if it hap- 
pened, as it happens in the country of the fairies or of Mother 

spite of its irony, abounds in a mysticism not found in the Au'kio? t) oi/os. A brief 
sketch of Lucian's work may be found in the Encyclopsedia Britannk-a, 
9th ed., under the article "Lucius." On Apuleius, and the relation of his 
work to that of Lucian, cf. Teuffel, Gesch. d. Rom. Lit., § 367, 3, 4th ed., 
Leipzig : B. G. Teubner, 1882 ; § 367, 1, 5th ed. by Ludwig Schwabe, Leipzig : 
Teubner, 1890, and from this ed., the English translation in 2 vols., by Geo. 
C. W. Warr, M.A., Geo. Bell and Sous, London, 1891. — Tr. 

1 Xicolas Tulp, 1.59:^1674, a Dutch physician and magistrate, in Bk. III., 
chap. .t6, of his Ohi^ervdtwnum. medicarum lihritres, Amsterdam, 1641, 8th ed., 
revised with additions, Leyden, 1752. — Te. 



CH. xxvii] ON HUMAN UNDERSTANDING 245 

Goose, that a parrot was a transforiued daughter of a king and 
became known as such while speaking, doubtless her father 
and mother would caress her as their daughter whom they 
thought they possessed though concealed under this strange 
form. I should not oppose myself, however, to him who should 
say that in the Golden Ass as the self or the individual re- 
mained for the sake of the same immaterial spirit, so Lucius 
or the person remained for the sake of the apperception of 
this ego, but that this is no longer a man ; asQn fact it seems 
necessary to add something of the figure and constitution of 
the body to the definition of man, when we say that he is a 
rational animal ; otherwise in my view the genii would also be 
menj 

§ 9. Ph. The word person carries with it a thinking and 
intelligent being, capable of reason and reflection, that can 
consider itself indeed as the same, as one and the same thing 
which thinks at different times and in different places ; which 
it does only by that consciousness ^ which it has of its own 
acts. And this knowledge always accompanies our sensations 
and our present perceptions [when they are sufficiently dis- 
tinguished, as I have more than once before remarked] and it 
is by this that each one is to himself what he calls himself. 
It is not considered in this case whether the same self is con- 
tinued in the same or in different substances. For since 
consciousness ^ always accompanies thought, and is that which 
makes each one to be what he calls himself and by which he 
is distinguished from every other thinking being ; it is also in 
this alone that personal identity consists, or that which makes 
a rational being always to be the same ; and as far as this 
consciousness can be extended over actions or thoughts already 
past, so far the identity of this person extends, and the self 
is at present the same as it was then. 

Th. [I am also of this opinion that consciousness or the 
perception of the ego proves a moral or personal identity. 
And it is by this that I distinguish the incessahility ^ of the 
soul of an animal from the immortality of the soul of man ; 

1 The French is " sentiment." — Tr. 

2 The French text is "la conscience {conscious7iess ou conscienciosite)," 
Gerhardt; " consciosite," Ertlmann and Jacques. — Tr. 

3 The French is " incessabilitc," i-c. continuity or perpetuity. — Tii. 



24(5 l.KlMNirZ'S iKirHilK OF LOCKE [bk. ii 

both preserve physical and real identity, but as for man, he is 
couformeil to the rules of diviue providence so that the soul 
preserves also identity moral and apparent to ourselves, in order 
to eonstitute the same person, cai)able consequently of feeling 
chastisements and rewards. It seems that you, sir, hold that 
this apparent identity could be preserved, if there were no 
real identity. I should think that that might perhaps be by 
the absolute power of God, but according to the order of things, 
identity apparent to the person himself who perceives the 
same, supposes real identity to every jiroximate transition, 
accompanied by reflection or perception of the ego, a perception 
intimate and immediate naturally incapable of deception. If 
man could be merely a machine and with that have conscious- 
ness, it would be necessary to be of your opinion, sir ; but I 
hold that this case is not possible at least naturally. jSTeither 
would I say that x>ersonal identity and even the self do not 
dwell in us and that I am not this ego which has been in the 
cradle, under pretext that I no more remember anything of 
all that I then did. It is sufficient in order to find moral 
identity by itself that there be a middle bond of consciousness 
between a state bordering upon or even a little removed from 
another, although a leap or forgotten interval might be mingled 
therein. Thus if a disease had caused an interruption of the 
continuity of the bond of consciousness so that I did not know 
how I came into the present state, although I remember things 
more remote, the testimony of others could fill the void in my 
memory. I could even be punished upon this testimony, if I 
had just done something bad of deliberate purpose in an inter- 
val that I had forgotten a little after on account of this 
disease. And if I had just forgotten all past things and^ 
would be obliged to let myself be taught anew even to my 
name and even to reading and writing, I could always learn 
from others my past life in m}^ previous state, as I have kept 
my rights without its being necessary for me to share them 
with two persons, and to make me the heir of myself. All 
this suffices to maintain moral identity, which makes the same 
person. It is true that if others should conspire to deceive 
me (as I might indeed be deceived by myself, by some vision, 
dream, or illness, believing that what I had dreamed had hap- 
1 Gerhardt reads : "et"; Erdmann and Jacques : " que," so that. — Tr. 



CH. xxvii] ON HUMAN UNDERSTANDING 247 

pened to me) the appearance would be false. But there are 
cases in which we can be morally certain of the truth upon the 
relation of another, and with God whose social connection 
with us constitutes the principal point of morality, the error 
cannot have place. As for the self, it will be well to dis- 
tinguish it from the phenomenon of self and from conscious- 
ness. The self constitutes identity real and physical, and the 
2)henomenon of self, accompanied by truth, joins thereto per- 
sonal identity. Thus not wishing to say that personal iden- 
tity extends no farther than memory, I would say still less 
that the self or physical identity depends upon it. Eeal and 
personal identity is proved with the utmost possible certainty 
by present and immediate reflection ; it is proved sufficiently- 
for ordinary purposes by our memory of the interval or by the 
conspiring testimony of others. But if God should change in 
an extraordinary manner real identity, personal identity would 
remain, provided man preserved the appearances of identity, 
as well the internal (that is to say, consciousness) as the 
external, like those which consist in that which appears to 
others. Thus consciousness is not the sole means for consti- 
tuting personal identity, and the testimony of another or even 
other proofs can supply it. But there is some difficulty if 
contradiction occurs between those diverse appearances. Con- 
sciousness may be silent as in forgetfulness ; but if it should 
alter very clearly things which were contrary to the other 
appearances, we should be embarrassed in the decision and as 
it were suspended sometimes between two possibilities, that 
of the error of our memory and that of some deception in 
external appearances.] 

§ 11. Ph. [You will say] that the members of the body of 
every man are a part of himself [and that thus, the body 
being in a perpetual flux, the man cannot remain the same]. 

Th. [I should rather prefer to say that (he I and the He are 
without parts, because it is said, and witli reason, that the 
same substance, or the same physical ego, is really preserved. 
But we cannot say, speaking according to the exact truth of 
things, that the same whole is preserved wlien a part is lost. 
Now whatever has corporeal parts cannot fail to lose some of 
them at every moment.] 

§ 13. Ph. The consciousness whic^li one has of his past 



248 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

actions cannot be transferred from one thinking substance to 
anotiior [and it would be certain that the same substance 
abides, because we feel ourselves the same], if this conscious- 
ness were a single and indeed an individual act [i.e. if the act 
of rertecting were the same as the act upon which you reflect 
in perceiving it]. But as it is only an actual representation 
of a past act it remains to be shown how it is impossible for 
what has never really been to be represented to the mind as 
truly having been. 

Th. [Memory after an interval may deceive ; we have ex- 
perienced it often, and there are means of conceiving a natural 
cause of this error. But present or immediate memory, or the 
memory of what passed immediately before, i.e. the conscious- 
ness or reflection which accompanies internal action, cannot 
naturally deceive ; otherwise we should not be certain indeed 
that we think of this or that thing, for this statement is 
made internally only of the action already past, and not in 
connection with the action itself. Xow if these internal, 
immediate experiences are not certain, there will be no truth 
of fact of which we can be assured. And I have already said 
that there may be intelligible reasons for the error which ex- 
poses itself in perceptions mediate and external, but in those 
immediately internal we cannot find any unless by recurring 
to the omnipotence of God.] 

§ 14. Ph. As for the question whether the same immaterial 
substance remaining there may be two distinct persons, see 
upon what it is based. It is this : If the same immaterial 
being can be deprived of all consciousness (sentiment) of its past 
existence, and lose it wholly, without the power of ever recov- 
ering it, so that beginning, so to speak, a new account from a 
new period, it has a consciousness (conscience) which cannot 
extend beyond this new state. All those who believe in the 
pre-existence^ of souls are evidently of this mind. I have seen 

1 I.e. existence before this earthly life. The doctrine was set forth with 
more or less fulness by the Pythagoreans, Plato, Philo, Origen, and more 
recently, among others, by Lessing, Erziehuncj des Menschenf/eschlechtes, 
§ 94 s^. ; Kant, Die Relif/ion innerhalb der Grenzen der blossen Vernunft, 
Bk. I., 4; Julius Miiller, Die christ. Lehre von der Siinde, Bk. IV., chap. 4, 
Vol. 2, pp. 486 sq., Breslau, 1844, and English translation of the same, 2d ed., 
from the 5th German ed., Halle, 1866, Vol. 2, pp. .357 .■<q., Edinburgh: T. & T. 
Clark, 1868. The doctrine has been used chiefly to explain the origin of 



CH. xxvii] ON HUMAN UNDERSTANDING 249 

a man who was persuaded that his soul had been the soul of 
Socrates ; and I can assure you that in the post he filled and 
which was not one of little importance he passed for a very- 
rational man, and he appeared by his works which have seen 
the light to lack neither intelligence nor learning. Now souls 
being ^ indifferent to any portion of matter whatever this may be, 
as far as we can know it by their nature, this supposition 
(of the same soul passing into different bodies) involves 
no apparent absurdity. But he who now has no conscious- 
ness of that which Nestor or Socrates ever did or thought, 
does he or can he conceive himself the same person as Nestor 
or Socrates? Can he take part in the actions of these two 
ancient Greeks? Can he attribute them to himself or think 
them his own actions rather than those of some other man 
who has already existed? He is no more the same person 
with one of them than if the soul now present in him had 
been created when it began to animate the body which it now 
possesses. This would no more contribute to make him the 
same person as Nestor, than if some of the particles of matter 
which once formed part of Nestor were now a part of this 
man. For the same immaterial substance without the same 
consciousness no more makes the same person to be united to 
such or such a body than tJte same x>artides of matter, united to 
a body without a common consciousness, can make the same 
person. ^ 

Th. [An immaterial being or a spirit cannot he stripped 
oi all perception of its past existence. There remain for it 
some impressions of all that has formerly happened to it, and 
it even has some presentiments of all that will happen to it ; 
but these feelings are most often too small to be capable of 
being distinguished and perceived, although they may perhaps 
sometime be developed. This continuation and bond of per- 

evil or sin; but it is an explanation which does not explain, its assumed solu- 
tion being merely an evasion of the real difficulty by pushing the problem 
back unsolved into past time. Cf. O. Ptleiderer, Relifjionsphilosophie auf 
gesch. Grundlarje, Vol. 2, p. 382, 2d ed., Berlin: G. Reimer, 1884; English 
translation. Vol. 4, p. 29, London : Williams & Norgate, 1888. For a critique 
of the theory as held l)y Julius Miiller, vf. I. A. Dorner, System d. chrintlichcn 
Glauhenslehre, § 77, 3 ; § 82, 2, Berlin : Wm. Hertz, 1881 ; English translation, 
Edinburgh: T. & T. Clark, 1882. — Tr. 

1 Gerhardt and Jacques read: "les ^raes estaut" (" etaut," J.) ; Erdmann 
reads: "taut." — Tr. 



250 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 



ceptions constitutes in reality the same individual, but the 
a] 'percept ions {i.e. when past feelings are perceived), prove 
besides a moral identity and make real identity appear. . The 
pre-oxistence of souls does not appear to us through our per- 
ceptions, but if it were true, it might sometime make itself 
known. Thus it is not reasonable that the restitution of 
memory becomes forever impossible, the insensible percep- 
tions (whose use I have set forth on so many important occa- 
sions) serving here, moreover, to preserve the seeds. The late 
Henry More, a theologian of the English church, was con- 
vinced of the truth of pre-existence and has written in its 
defence.^ The late M, Van Helmont, the son, went much 
farther, as I just said, and believed in the transmigration of 
souls, but always into bodies of one and the same species, so 
that according to him the human soul always animated a man. 
He believed with some Eabbis in the passage of the soul of 
Adam into the Messiah as into the new Adam. And I do not 
know but that he thought he had himself been some ancient, 
altogether clever man that he ■was elsew^here. i^ow if this pas- 
sage of souls was true, at least in the possible way that I have 
explained above (but which does not appear probable), i.e. 
that souls, keeping their subtile bodies, pass at once into other 
coarse bodies, the same individual would always subsist in 
Nestor, in Socrates, and in any modern, and he could even 
make his identity known to any one wdio w^ould penetrate 
sufficiently into his nature, on account of the impressions or 
marks which would there remain of all that jSTestor or Soc- 
rates have done, and W'hich any genius sufficiently penetrat- 
ing could there read. But if the modern man had no means 
internal or external of knowing what he had been, it w^ould be 
as far as the moral is concerned as if he had not been. But 
it appears that nothing is neglected in the world in relation 
even to the moral, because God is the monarch thereof whose 
government is perfect. Souls according to my hypothesis are 
not indifferent regarding any portion of matter whatever, as it 
seems to you ; on the contrary, they originally express those 
portions to which they are and ought to be united by nature. 

1 Cf. Opera, 1, 750-754, London, 1679; following the Kabbala, he thinks all 
souls were created at the same time as the world, 2, 539; and, like Leibnitz, 
regards them as always united with some kind of matter, 2, 395, 396. — Tr. 



CH. xxvii] ON HUMAN UNDERSTANDING 251 

Thus, if they pass into a new body coarse or sensible, they 
would always preserve the expression ^ of all that they had 
perceived in the old, and it would even be necessary for 
the new body to manifest it so that the individual continuity 
will always have its real marks. But whatever our past state 
may have been, the effect it leaves cannot always be for us 
apperceivahle. The clever author of the Essay on Understand- 
ing, whose views you had espoused, had remarked (Bk. II., 
chap. 27. On Identity, § 27) that a part of these suppositions 
or fictions of the passage of souls, assumed as possible, is 
founded upon the common view of the mind as not only inde- 
pendent of matter but also as indifferent to every sort of mat- 
ter. But I hope that what you have said, sir, on this subject 
here and there will serve to clear up this doubt and to make 
better known what is naturally possible. We see thereby 
how the acts of an ancient might belong to a modern who had 
the same soul, although he did not perceive them. But if he 
should come to recognize it, still more would personal identity 
follow. For the rest a portioyi of matter passing from one 
body into another does not constitute the same human indi- 
vidual, nor what is called the ego, but it is the soul which 
constitutes it.] 

§ 16. Ph. It is, however, true that I am as much concerned 
and as justly responsible for an action done a thousand years 
since, which is now adjudged as mine by this present con- 
sciousness (self-consciousness^) thereof, as having been done 
by myself, as I am for what I have just done in the j)reced- 
ing moment. 

Th. [This view of having done something may deceive in 
distant actions. Men have taken as true by force of repetition 
what they dreamed, or what they invented ; this false view 
may embarrass, but it cannot make them punishable, unless 
others agree therewith. On the other hand, you can be respon- 
sible for what you have done, when you have forgotten it, 
provided the action be verified elsewhere.] 

§ 17. Ph. Every one finds every day that while his little 

1 Gerliardt and Erdmann read: " I'expression " ; Jacques: " rimpression." 
— Tr. 

- Gerhardt's reading ; Erdmann and Jacques have, as before (p. 245, note 2) , 
" consciositc ou consciousness." — Tr. 



LTC LKIBMTZ'S CRITIQUE OF LOCKE [bk.ii 

fint^iM- is c'omiiivlu'iKU'd iiiulor this consciousness, it constitutes 
as niucli a part of liiint<i'lf {vi him) iis that which is most so. 

Th. [1 have said (§11) why I would not advance the view 
that my linger is a part of me ; but it is true that it belongs to 
me and tliat it constitutes a part of my body.] 

Ph. [Those who hold another view will say that] in the 
event of this little linger being separated from the rest of the 
body, if this consciousness accompanies the little linger and 
leaves the rest of the body, it is evident that the little finger 
would be the person, the same person, and that then the self 
would have notliing to do with the rest of the body. 

Th. [Nature does not admit these fictions, Avliich are de- 
stroyed by the System of Harmony or the perfect correspon- 
dence of tlie soul and the bod}'.] 

§ 18. Ph. It seems, however, that if the body should con- 
tinue to live and to have its particular consciousness, in which 
the little finger had no share, and that meanwhile the soul 
was in the finger, the finger could not own any of the actions 
of the rest of the body, and we could no longer impute them 
to it.i 

Til. [The soul also which would be in the finger would not 
belong to this body. I admit that if God caused conscious- 
nesses to be transferred to other souls, it would be necessary 
to treat them in accordance with moral notions, as if they 
were the same ; but this would disturb the order of things 
without reason, and make a divorce between the appercepti- 
ve and the truth, which is conserved by the insensible percep- 
tions, which would not be reasonable, because the perceptions 
insensible at present may some day be developed, for there is 
nothing useless, and eternity gives a large field for changes.] 

§ 20. Ph. Human laws do not punish the madman for the 
acts which the sober ^ man does, nor the sober man for what 
the madman does, thereby making them two persons. Thus 
they say : he is beside himself. 

Th. [The laws threaten to chastise and promise to recom- 
pense in order to prevent bad and further good acts. Now a 
madman may be such tliat the threats and i^romises do not 
operate sufficiently upon him, reason no longer being master ; 

1 Locke reads: " him," Philos. Worlcs, Vol. 1, p. 475 (Bohn's eel.). — Tr. 

2 Locko's word; Philon. Woi-ks, Vol. 1, p. 475 (Bohn's ed.). — Tr. 



cii. xxvii] ON HUMAN UNDERSTANDING 253 

thus in proportion to his weakness the severity of the pain 
shouhl cease. On the other hand we wish tlie criminal to feel 
the effect of the evil he has done in order that he may fear 
further to commit crimes, but the madman not being sensitive 
enough, we are well content to wait a good while in order to 
execute the sentence which punishes him for what he did 
when sober. Thus what the laws or the judges do in these 
instances comes not from the conception of two persons.] 

§ 22. Ph. In fact in the party whose opinions I represent 
to you, this objection is made, that if a man who is drunk and 
who is afterwards no longer drunk, is not the same person, he 
should not be punished for what he did while drunk, since he 
is no longer conscious of his act. But they reply that he is 
altogether as much the same person as a man who during his 
sleep walks and does many other things and who is responsi- 
ble for all the evil he has happened to do in that state. 

Th. [There is much difference between the acts of a 
drunken man and those of a true and recognized somnambu- 
list. We punish drunkards because they can avoid drunken- 
ness and can even have some memory of pain while drunk. 
But it is not so much within the power of somnambulists to 
abstain from their nocturnal walk and from what they do. 
But if it were true that by giving them a good flogging we could 
make them stay in bed, we should be right in doing it, and we 
should not fail either, although this Avould be rather a remedy 
than a punishment. In fact it is said that this remedy has 
restored them.] 

Ph. Human laws punish both in accord with a justice con- 
formed to the mode in which men understand things, because 
in these sorts of cases they cannot certainly distinguish what 
is real from what is counterfeit ; thus ignorance is not re- 
ceived as an excuse for what they have done while drunk or 
asleep. The deed is proved against the one who has done it, 
and you cannot prove in his case lack of consciousness. 

Th. [The question is not so much about this, as about what 
must be done when it has been verified, as it may be, that the 
drunkard or somnambulist were beside themselves. In this 
case the somnambulist would be considered only as a maniac ; 
but as drunkenness is voluntary, and the disease is not, the one 
is punished but not the other.] 



254 LEIBNITZ'S ClUTK^UE UF LUCKE [uk. ii 

Ph. But iu tlie great and terrible day of judgment, when 
the secrets of all hearts shall be uncovered, it is right to think 
that no one will have to answer for what is wholly unknown 
to him and that each one will receive what is due him, his 
own conscience accusing or excusing ^ him. 

Th. I do not know whether it will be necessary for the 
memory of man to be exalted at the day of judgment in order 
for him to remember all he had forgotten, or whether the 
knowledge of others and above all of the just judge who can- 
not be deceived will not suffice. We might devise a fiction lit- 
tle agreeing with the truth, but nevertheless conceivable, to the 
effect that a man at the day of judgment believed he had 
been bad and that the same appeared true to all other created 
spirits, who would be able to judge of it, without its having 
been true : could we say that the supreme and just judge, who 
alone knows the contrary, could condemn this person and 
judge contrary to his knowledge ? - Yet it seems that that 
would follow from the notion you gave of moral personality. 
You will perhaps say that if God judges contrary to appear- 
ances he will not be sufficiently glorified and will bring pain 
upon others ; but the reply could be made that he is for him- 
self his unique and supreme law, and that in this case others 
should consider themselves mistaken.] 

§ 23. Ph. Could we suppose either tico distinct and incom- 
municable consciousnesses acting by turns in the same body, 
the one constantly during the day, the other by night, or that 
the same consciousness acts at intervals in two different bodies ; 
I ask if, in the first case, the day and night man, if I may 
so express myself, would not be two as distinct persons as 
Socrates and Plato, and in the second case would he not be a 
single person in two distinct bodies ? It matters not that this 
same consciousness which affects two different bodies, and 
these consciousnesses which affect the same body at different 
times, belong the one to the same immaterial substance, and 
the two others to two distinct immaterial substances, which 
introduce these different consciousnesses into these bodies, 

1 Erdmann and Jacques omit: "ou excuse." — Tr. 

2 Gerhardt reads : " juger centre ce qu'il salt?" Erdmann and Jacques: 
" juger centre ce qu'ils font?" i.e. "pass a judgment contrary to what they 
do." — Tr. 



CH. xxvii] ON HITMAN UNDERSTANDING 255 



since personal identity would equally be determined by the 
consciousness, whether that consciousness were attached to 
some individual immaterial substance or not. Further, an 
immaterial thinking thing may sometimes lose sight of its 
past consciousness, and recall it anew. Now suppose these 
intervals of memory and forgetfulness return with every day 
and night, then you have two persons with the same immate- 
rial spirit. Whence it follows that the self is not determined 
by the identity or diversity of substance, Avhich it cannot be 
sure of, but only by the identity of consciousness. 

Th. [I admit that if all the appearances were changed and 
transferred from our spirit to another, or if God made an 
exchange between two spirits, giving the visible body and the 
appearances and consciousnesses of the one to the other, per- * 
sonal identity, instead of being attached to that of substance, 
Avuiikl follow the constant appearances which human morality 
must have in view ; but these appearances would not consist^ 
in the consciousnesses alone ; and it will be necessary for God to 
make the exchange not only of the apperceptions or conscious- 
nesses of the individuals in question, but also of the appear- 
ances which present themselves to others regarding these 
persons, otherwise there would be a contradiction between 
the consciousnesses of the one and the testimony of the others, 
which would disturb the moral order of things. But you 
must also agree with me that the divorce between the insensi- 
ble and sensible world, i.e. between the insensible perceptions 
which would remain in the same substances, and the appercep- 
tions which would be changed, would be a miracle, as when 
you suppose that God makes the vacuum ; for I have stated 
above why that is not in agreement with the natural order. 
Here is another supposition much more suitable : it may be 
that in another place in the universe or at another time a globe 
may be found which does not differ sensibly from this earthly 
globe, in which we live, and that each of the men who inhabit 
it does not differ sensibly from each of us who corresponds to 
him. Thus there are at once more than a hundred million pairs 
of similar persons, i.e. of two persons with the same appear- 
ances and consciousnesses ; and God might transfer spirits 
alone or with their bodies from one globe to the other without 
their perceiving it ; but be they transferred or let alone, what 



256 LEIBNITZ'S CRITIQUE OF LOCKE [inc. n 

will yon say of their person or self according to your authors ? 
Are they two persons or the same? since the consciousness 
and tlie internal and external appearance of the men of these 
globes cannot make the distinction. It is true that God and 
the spirits capable of seeing the intervals and external rela- 
tions of times and places, and even internal constitutions, 
insensible to the men of the two globes, could distinguish 
them ; but according to your hypotheses consciousness alone 
discerning the persons without being obliged to trouble itself 
with the real identity or diversity of the substance, or even 
of that which would appear to others, how is it prevented 
from saying that these two persons who are at the same time 
in these two similar globes, but separated from each other by 
an inexpressible distance, are only one and the same person ; 
which is, however, a manifest absurdity. For the rest, speak- 
ing of what may be in the course of nature, the two similar 
globes and the two similar souls of the two globes would 
remain so only for a time. For since there is an individual 
diversity, this diffV-rence must consist at least in the insensible 
constitutions which must be developed in the course of time.] 

§ 26. Fh. Suppose a man punished now for what he has 
done in another life and of which he could cause himself to 
have absolutely no consciousness; what difference is there 
between such treatment and that which would be done him in 
creating him miserable ? 

Th. [The Platonists, disciples of Origen, some Hebrews 
and other defenders of the pre-existence of souls believed that 
the souls of this world were placed in imperfect bodies, in 
order to suffer for the crimes committed in a preceding world. 
But it is true, if they neither know nor have ever learned the 
truth, neither by recall of memory, nor by any traces, nor by 
the knowledge of another, you cannot call it punishment ac- 
cording to ordinary notions. There is, however, some room 
for doubt, while speaking of punishments in general, whether 
it is absolutely necessary that those who suffer should one day 
learn the reason for their suffering, and whether it w^ould not 
very often suffice that better informed minds should find 
therein a motive for glorifying the divine justice. However, 
it is more likely, at least in general, that the sufferers will 
know the reason of their suffering.] 



CH. xxvii] ON HUMAN UNDERSTANDING 257 

§ 29. Ph. [Perhaps in the main you can agree with my 
author who concludes his chapter on identity by saying : that 
the question whether tlie same man abides, is a question of 
name, according as you understand by man eitlier the rational 
spirit alone or the body alone of this form which is called 
human, or finally the spirit united to such a body. In the first 
case the spirit separated (at least from the coarse body) will 
be still the man ; in the second an ourang-outang, perfectly 
similar to us, reason excepted, would be a man ; and if man 
were deprived of his rational soul and received a soul of an 
animal, he would continue the same man. In the third case 
both must remain together with the union itself ; the same 
spirit, and the same body in part, or at least equivalent, as 
far as the sensible corporeal form is concerned. Thus you 
could continue the same being physically or morally, i.e. the 
same person without remaining man, in case you consider this 
figure an essential to man according to this last sense.] 

Th. [I admit that in this respect it is a question of name, 
and in the third sense the same animal is as it were now 
caterpillar or silk-worm and now butterfly, and some as it 
were have imagined that the angels of this world were men in 
a past world. But we have devoted ourselves in this confer- 
ence to discussions more important than those about the 
meaning of words. I have shown you the source of true 
physical identity ; I have made it appear that morality con- 
tradicts it no more than memory ; that they cannot always 
assign physical identity to the person indeed, whose (iden- 
tity) is at stake, nor to those who are in connection with him; 
but that nevertheless they never contradict physical identity 
and never are completely ^ divorced from it ; that there are 
always some created spirits who know or may know what it 
is ; but that there is room to consider that what is indifferent 
regarding the persons themselves can be so only for a time.] 

1 Erdmann and Jacques omit : "entier." — Tr. 
S 



258 LKlli.Ml/S C'KiriQL'E OF LOCKE [i:k. 



CHAPTER XXVIII 

OF SOME OTHER RELATIOXS, AXD ESPECIALLY OF MORAL 
BELATIOXS 

§ 1. Ph. Besides the relations founded upon time, space, 
and causality, of which we have just been speaking, there are 
an infinite number of others, some of which I am going to 
propose for discussion. Every simple idea capable of parts 
and of degrees, furnishes an occasion for comparing the sub- 
jects in which it is found, for example, the idea of more (or 
less or equally) white. This relation may be called xiropor- 
tional. 

Th. [There may be, hoAvever, excess without proportion ; 
and this is in reference to a magnitude which I call imjjerfect, 
as when ^ye say that the angle which the ray makes with the 
arc of its circle is less than a right angle, for it is impossible 
that there be a proportion between these two angles, or 
between one of them and their difference, which is the angle 
of contingence.] 

§ 2. Ph. Another occasion of comparing is furnished by 
the circumstances of origin which found the relations of father 
and child, brothers, cousins, countrymen. With us people 
seldom think of saying this bull is grandfather of such a calf, 
or these two pigeons are cousins-german ; for languages are 
proportioned to use. But there are countries in w^hicli men less 
curious about their own pedigree than about that of their 
horses have not only names for each particular horse, but also 
for their different degrees of relation. 

Th. [We can furthermore join the family idea and names 
to those of relationship. It is true we do not observe under 
the empire of Charlemagne and for a sufficiently long time 
before and after family names in Germany, France, and Lom- 
bardy. It is moreover not long that there have been families 
(even noble) in the ISTorth who had no name, and in which a 
man would be recognized in his natal place only by calling his 
name and that of his father, and besides (in case he trans- 
planted himself) by joining to his own the name of the place 



cii. xxviii] ON HUMAN UNDERSTANDING 250 

whence he came. The Arabs and the Turcomans have also the 
same custom (I believe), having but few particular family 
names, and content themselves with naming the father and 
grandfather, etc., of any one, and they pay the same honor to 
their valuable horses, which they call by a proper name and 
the name of the father and even beyond. Thus they spoke of 
the horses which the Monarch ^ of the Turks sent to the 
emperor after the peace of Carlowitz ; ^ and the late count 
of Oldenburg, the last of his branch, whose studs were 
famous, and who lived a very long time, had genealogical 
trees of his horses so that he could prove their nobility, 
and went so far as to have portraits of their ancestors (imag- 
ines majonmi) which were so much in demand among the 
Romans. 'But to return to men, there are among the Arabs 
and the Tartars names of tribes, which are like great families, 
which are much enlarged in the course of time. And these 
names are taken either from the progenitor as in the time of 
Moses, or from the place of abode, or from some other circum- 
stance. Mr. Worsley, an observing^ traveller, who is inforined 
of the present state of Arabia Deserta, where he has been for 
some time, affirms that in all the countries between Egypt and 
Palestine, and where Moses passed, there are to-day only three 
tribes, who can bring together five thousand men, and that 
one of these tribes is called Scdi from the progenitor (as I 
believe) whose tomb posterity honors as that of a saint, casting 
upon it dust which the Arabs put upon the heads of themselves 
and their camels. For the rest consa7igiiinity exists when there 
is a common origin of those whose relation is considered ; but 
we could say there is cdliance or affinity between two persons, 
when they may have consanguinity with one and the same 
person without there being any for that reason between them- 
selves, which happens through the intervention of marriages. 
But as it is not customary to say that there is affinity between 
husband and wife, although their marriage may cause affinity 
in relation to other persons, it would perhaps be better to 
say that there is affinity between those who would have con- 

1 Erdmaiin and Jacques read: "grand Seigneur." — Tr. 

2 Jan. 26, 1()9!». — Tk. 

3 Erdmann and Jacques read : "curieux"; Gerhardt. roads: "observatif." 
— Tk. 



2ti0 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

sanguinity between themselves if liusband and wife were 
taken as one and the same person. 

§ o. Ph. The foundation of a relation is sometimes a moral 
riglit, as the relation of a general of an army or of a citizen. 
These relations depending upon the agreements men have 
made between themselves are voluntary or by institution, and 
may be distinguished from the natural. Sometimes the two 
correlatives have each its name, as patron and client, general 
and soldier. But it is not so always ; as, for example, it is not 
so in the case of those who are related to the chancellor. 

Til. [There are sometimes natural relations which men have 
invested and enriched with certain moral relations, as, for 
example, children have the right to claim the legitimate por- 
tion of the estate of their fathers or mothers ; young persons 
are under certain restraints and the aged have certain immu- 
nities. But it also happens that some relations are taken as 
natural which are not so ; as when the laws say that the 
father is he who married the mother within the time which 
makes it possible for the child to be attributed to him ; and 
this substitution of the instituted in the place of the natural is 
sometimes only j^resumj^tion, that is to say, a judgment which 
causes that to pass as true which perhaps is not so, whilst its 
falsity is not at all proved. Thus it is that the maxim : pater 
est quern nuptioe demonstrant is understood in Roman law and 
among the most of the peoples where it is received. But they 
tell me that in England it avails nothing in proving his alibi; 
l^rovided he has been in one of the three kingdoms, so that 
the presumption in that case changes into Jiction or into what 
some doctors call j^i'^^sumtio juris et de jure.'\ 

§ 4. Ph. A moral relation is the conformity or disagreement 
which is found between the voluntary acts of men and a rule 
which makes us judge whether they are morally good or bad. 
§ 5. And moral good or moral evil is the conformity or the 
opposition which is found between voluntary acts and a cer- 
tain law which brings upon us good or evil (physical) by the 
will and power of the lawgiver (or of him who wills to main- 
tain the law) and it is this we call reu-ard and punishment. 

Th. [Authors, as clever as he whose views you, sir, repre- 
sent, are allowed to adapt their terms as they think proper. 
But it is also true that according to this notion one and the 



CH. xxviii] ON HUMAN UNDERSTANDING 261 

same act would be morally good and morally bad at the same 
time under different legislators, entirely as our clever author 
understood virtue above as that which is praised, and conse- 
quently the same act would be virtuous or not according to 
the opinions of men. Now that not being the ordinary sense 
that is given to morally good and virtuous acts, I prefer for 
myself, to take as the measure of moral good and of virtue 
the invariable rule of reason which God is charged with main- 
taining. We can also be assured that by his mediation all 
moral good becomes physical,' or as the ancients say, every 
thing virtuous is useful^; while in order to express the notion 
of the author, it would be necessary to say that moral good or 
evil is an imposed or instituted good or evil, which he who has 
the power tries to make us follow or shun by punishments 
and rewards. The good is that which by the general institu- 
tion of God is conformed to nature or to reason.] 

§ 7. Ph. There are three sorts of laws : the divine law, the 
civil laio, and the law of opinion or rex)utation. The first is 
the rule of sins or duties, the second of actions criminal or 
innocent, the third of virtues or vices. 

Th. [According to the ordinary sense of terms virtties and 
vices differ from duties and sins only as habits differ from 

1 What does Lei))uitz here mean hy " physical " ? Possibly " physical " is 
here equivalent to " real," i.e. actual, concrete, objectively realized as distin- 
,<;uished from that whicli is purely subjective and abstract, and exists in idea 
only ((/. Bk. II., chap. 27, § 9, Th. prozjejin., ante, p. 217, line 7, where the two 
terms are united in one plirase " real and physical," and seem to be mutually 
interpretative and emphatic). Or, possibly, "physical" is here used in the 
sense of "natural," the meaning of the passage being that moral good is 
realized by the mediation of God through the natural forces and in accord 
with the natural laws of the universe, which with Leibnitz have their ultimate 
source and ground in the nature of God and his cl)oice of " tlie best and most 
perfect," as the universal principle of creation. The true view of the world 
is, according to Leil)nitz, both physico-mechanical and moral-teleological, tlie 
two finding a higher unity in this principle of " the best and most perfect," 
the moral-teleological i)revailing in case of collision, because of this princi- 
ple and because tlie physical is in its last analysis and ground sjjiritual and 
Ijossessed of an inner teleological character whicli is realized by means of 
mechanism while resting upon the principle of the divine choice of tlie best. 
Cf. Discours de Metaphynigue, § 19 sq., Gerhardt, 4, 444 sq.; letter to Bayle, 
G. .3, .54; Erdmann, lOfi. — Tr. 

2 Cf. Cicero, Be Offinix, Bk. III., chaps. .3 and 7, who shows on the author- 
ity of Pansetius and others that the virtuous and the useful — honestum and 
utile — are identical, a cliief point of the Stoic philosnpliy. Cf. also Zeller, 
Lie Philos. d. Gricch., III., 1 [Vol. 5] , p. 212, 3d ed. ISSO. — Tr. 



LEIBNITZ'S CRITIQUE OF LOCKE [mc. 



actions, and virtue and vice are not understood as something 
dependent upon opinion.^ A great sin is called a crime, and 
the innocent is not opposed to the criminal but to the blame- 
ivorthy. The divine law ^ is of two sorts, natural and positive. 
Civil law is positive. The law of reputation deserves the 
name of law only improperly, or is comprised under the 
natural law, as though I said, the law of health, the law of 
the family, when actions naturally attract some good or evil, 
as the approbation of another, health, gain.] 

§ 10. Ph. The claim is in fact everywhere made that the 
terms virtue and vice signify actions good and bad in their 
nature, and so far as they are really applied in this sense, vir- 
tue agrees perfectly with the divine (natural) law. But what- 
ever the claims of men, it is evident^ that these names, con- 
sidered in their particular aj^plications, are constantly and 
solely attributed to such or such actions as in each country or 
in each society are reputed honorable or shameful : otherwise 
men tvould condemn themselves. Thus the measure of what is 
called virtue and vice is this approbation or this contempt, 
this esteem or this blame, which is formed by a secret or tacit 
consent. For although men united in political societies have 
resigned into the hands of the public the disposition of all 
their forces, so that they cannot employ them against their 
fellow-citizens beyond what the law permits, they nevertheless 
always retain the power of thinking well or ill, of approval 
or disapproval. 

TJi. [If the clever author, who thus explains himself, shoidd 
declare with you, sir, that it has pleased him to assign this 
present arbitrary nominal definition to the terms virtue and 
vice, we could only say that it is allowed him in theory for the 

1 Leibnitz maintains, as against Locke's theory of relativity, the ahsohite 
and ohjective cliaracter of Moral Law. It is objective and universal, not sub- 
jective and particular ; not dependent upon the opinions of men, but grounded 
in "the general institution of God," and ultimately in his infinitely perfect 
moral nature, and is thus valid for and binding upon all moral beings as such. 
This is Moral Law absolute and ideal which changes not ; it is progressively 
and approximately attained or realized in the history of the individual and 
the race according to men's apprehension of its nature and requirements and 
their strength of purpose and effort in its pursuit. — Tr. 

2 Cf. the discussion of Moral Law, in Principles and Practice of Morality, 
pp. 79 57., by E. G. Robinson, D.D., LL.D., Ex-President of Brown University. 
Boston: Silver, Burdett & Co., 1888.— Tr. 

3 Locke has: "visible," Philos. Works, Vol. 1, p. 488 (Bohn's ed.). — Tr. 



CH. xxviii] ON HUMAN UNDERSTANDING 263 

convenience of expression for want perhaps of other terms ; but 
we shall be obliged to add that this meaning is not conformed 
to usage, nor indeed useful for edification, and that it would 
sound ill in the ears of many people, if any one should intro- 
duce it into practical life and conversation, as this author 
seems himself to admit in his preface. But it is (for us) to 
go on farther here, and although you admit that men claim to 
speak of tliat which is naturally virtuous or vicious according 
to immutable laws, you maintain that in fact they mean to 
speak only of that which depends on opinion. But it seems 
to me that by the same reasoning you could further maintain 
that truth and reason and all that could be named as most real, 
depends upon opinion, because men are mistaken when they 
judge of it. Is it not better then on all accounts to say, that 
men understand by virtue as by truth, that which is conformed 
to nature, but that they are mistaken often in its application ; 
besides they are mistaken less than they think, for what they 
praise ordinarily deserves it in certain respects. The virtue 
of drinking, i.e. of well carrying wine, is an advantage, which 
served Bonosus, in conciliating the Barbarians and in drawing 
from them their secrets.^ The nocturnal powers of Hercules, in 
which the same Bonosus claimed to resemble him, were no less 
a perfection. The craft of thieves was praised among the 
Spartans, and it is not the skill, but the unseasonable use 
which has been made of it, which is blamable, and those whom 
we harass in (time of) complete peace may serve sometimes as 
excellent partisans in time of war. Thus all depends upon the 
application and the good or bad use of the advantages you pos- 
sess. It is also very often true and should not be taken as a 
very strange thing, that men condemn themselves, as when they 
do what they blame in others, and there is often a contradiction 
between actions and words which scandalizes the public, when 
what a magistrate or preacher does and defends leaps to the 
eyes of the whole world.] 

§ 11. '-^ Ph. Everywliere that which passes as virtue is that 
which is thought worthy of praise. Virtue and praise are often 
designated by the same name. Su7it hie etiam sua proimia 
laudi, says Vergil {Aen. I. 461) and Cicero, Nihil habet natura 

1 C/. Vopiscus, Script, hist. Avr/ust., Vol. 2, pp. 21.3, 214, ed. Peter. — Tb. 

2 Gerhardt and Locke; Erdraann and Jacques have § 12. — Tk. 



•2(ii LElliNiTZ'S CKITIQUE OF LOCKE [uk. ii 

]>mestanlii(s quam honestatem, quam kmdem, quavi dignitatem, 
qnam di'cus.^ {Qiuesf. 2'hscuI. Bk. 2. chap. 20) and lie adds 
a little after: Ilisce ego jiluribus nominibus unavi rem dedamri 
volo} 

Th. [It is true that the ancients have designated virtue by 
the name honesty {Vhonneste), as when they have praised in- 
coctum generoso pectus houesto.- It is true also that honesty 
{rhonneste) has its name of honor or of i^raise. But this 
means not that virtue is that which is praised but that it is 
that Avhich is worthy of praise and wdiich depends upon truth, 
and not upon opinion.] 

Fh. Many do not think at all seriously of the km of God, or 
hope that they will one day be reconciled with its author, and 
as regards the km of the state they flatter themselves with im- 
punity. But they do not think that he who does anything 
contrary to the opinions of those with whom he associates, and 
to whom he wishes to commend himself, can avoid the pain of 
their censure and of their disdain. No one who retains any 
consciousness of his own nature can live in society constantly 
despised ; this is the force of the knc of reputation. 

Til. [I have already said that it is not so much the pain of a 
law, as a natural pain which the act draws upon itself. It is, 
however, true that many people are but little concerned about 
it, because ordinarily, if they are despised by some on account 
of some blameworthy act, they find accomplices or at least 
partisans, who do not despise them, if they are ever so little 
commendable in some other respect. They forget even acts 
the most infamous, and it often suffices to be bold and im- 
pudent like that Phormio of Terence in order that all may be 
overlooked. If excommunication produced a truly constant 
and general contempt, it Avould have the force of this law of 
which our author speaks : and it had in fact this force with the 
first Christians aud for them took the place of the right, which 
they lacked, to punish the guilty ; nearly as artisans maintain 
certain customs among themselves in spite of the laws, through 

1 The quotation is not exact. Cf. op. cit., ed. Klotz, Lipsiae, B. G. Teiib- 
ner, 1870, where the text reads thus: "Nihil enim hal)et i^raestantius, nihil 
quod magis expetat quam honestatem, quam laudem, qiiam dignitatem, quam 
deeus. Hisce ego pluribus noniinibus uiiam rem declarari volo, sed utor, ut 
quam maxime significem, pluribus." — Tr. 

2 Persius. Sat. 2, 74.— Tr. 



cii. xxix] ON HUMAN UNDERSTANDING 265 

the contempt which they show for those who do not observe 
them. And it is this which has also maintained duels con- 
trary to the ordinances. It would be desirable for the public 
to agree Avith itself and with reason in its praise and blame ; 
and that the great above all do not encourage the bad by laugh- 
ing at their bad actions, in which it oftenest seems that not he 
who has done them, but he who has suffered them is punished 
by contempt and ridiculed. We shall see also generally that 
men despise not so much vice as weakness and misfortune. 
Thus the law of reputation would need to be greatly reformed, 
and also to be better observed.] 

§ 19. Ph. Before leaving the consideration of relations, I 
would remark that we usually have a notion as clear or clearer 
of the relation than of its ground. If I believed that Sempronia 
took Titus from beneath a cabbage, as they used to tell little 
children, and that afterwards she had had Cains in the same 
manner, I should have as clear a notion of the relation of 
brother between Titus and Caius, as if I had all the knowledge 
of tlie midwives. 

Th. But when they once said to a child, that his little 
brother, who had just been born, had been drawn from a well 
(a reply which they make use of in Germany to satisfy the 
curiosity of children upon this subject) the child replied that 
he wondered that they did not throw him back again into the 
same well when he cried so much and disturbed his mother. 
The fact is this explanation did not make him know any rea- 
son for the love his mother showed for the child. We can say 
then that those who do not know the ground of relations have 
only concerning them what I call thoughts, surd in part and 
insufficient, although these thoughts may suffice in certain 
respects and upon certain occasions.] 



CHAPTER XXIX 

OF CLEAR AND OBSCUKE, DISTINCT AND CONFUSED IDEAS 

§ 2. Ph. We come now to some differences of ideas. Our 
simj)le ideas are dear when they are such as the objects them- 
selves, from whence they are received, represent or may 



o,;0 LF-TT^NITZ'S CRITIQUE OF LOCKE [kk. ii 

ivpreseut them with all the circumstances requisite to a well- 
ordered sensation or perception. While the memory retains 
them in this way, they are in this case clear ideas, and so far 
as they lack this original exactness or have lost anything so 
to speak of their first freshness, and are, as it were, tarnished 
or faded by time, so far are they obscure. Complex ideas are 
dear, when the simple ideas which compose them are clear and 
the number and order of these simple ideas are fixed. 

Th. [In a brief discourse on ideas,^ true or false, clear or 
obscure, distinct or confused, inserted in the " Leipsic Acts " 
of the year 1684, I have given a definition of clear ideas, 
common to the simple and complex and which gives the rea- 
son of what you say here. I said then that an idea is clear 
when it suffices to recognize and distinguish the thing: as 
when I have a very clear idea of a color, I shall not take 
another instead of that which I ask for, and if I have a clear 
idea of a plant, I shall distinguish it among other neighboring 
ones ; without this the idea is obscure. I believe that we have 
but few perfectly clear ideas of sensible things. There are 
colors which approach each other in such a way that we can- 
not distinguish them by memory, and yet we will sometimes 
distinguish them by placing one near the other. And when 
we think we have fully described a plant, we can bring one 
from the Indies which will have all we have put into our 
description and which will not cease making itself known as 
a different species : thus we can never perfectly determine 
species infamoe, or the lowest species.] 

§ 4. Ph. As a clear idea is that whereof the mind has such 
a full and evident perception as it receives from an external 
object operating duly upon a well-disposed organ ; so a distinct 
idea is that wherein the mind perceives a difference, which 
distinguishes it from every other idea ; and a confused idea is 
that which cannot be sufficiently distinguished from another 
from which it should be different. 

Th. [According to this notion which you give of the dis- 
tinct idea, I do not see how you distinguish it from the clear 
idea. This is why I have been wont to follow here the lan- 
guage of Descartes, with whom an idea may be clear and con- 

^ Meditationes de Cor/nitione, Veritate et Ideis. Cf. ante, p. 14, note 2; 
p. 227, notes. — Tr. 



xxix] ON HUMAN UNDERSTANDING 267 



fused at the same time ; and such are the ideas of sensible 
qualities, appropriate to the organs, such as color or heat. They 
are clear, for they are easily recognized and distinguished the 
one from the other, but they are not distinct, because they are 
not distinguished by what they include. Thus we cannot give 
a definition of them. We make them known only by examples, 
and for the rest we must say it is an indefinite somewhat, 
until we can decipher its contexture. Thus although in 
our view distinct ideas distinguish one object from another ; 
nevertheless, as the ideas clear, but confused in themselves, do 
so also, we call distinct not all those which are very discrimi- 
nating or which distinguish objects, but those which are well 
distinguished, i.e. which are distinct in themselves and dis- 
tinguish in the object the marks which make it known, which 
an analysis or definition of it gives ; otherwise we call them 
confused. And in this sense the confusion which reigns in 
ideas can be exempt from blame, being an imperfection of our 
nature; for we cannot discern the causes, for example, of odors 
and tastes, nor the content of these qualities. This confusion 
can, however, be blameworthy, when it is important and 
within my power to have distinct ideas, as, for example, if I 
took adulterated gold as the true, for want of making the 
necessary assays which contain the marks of good gold. 

§ 5. Ph. But you will say that there is no idea confused (or 
rather according to your view, obscure) in itself^ for it can be 
only such as it is perceived by the mind, and that distin- 
guishes it sufficiently from all others. § 6. And in order to 
remove this difficulty it is needful to know that the defect of 
ideas is related to names, and what renders it faulty is the 
fact that it can as well be designated by another name as the 
one which we use to express it. 

Th. [It seems to me that we ought not to make this depend 
upon names. Alexander the Great had seen (they say) in a 
dream a plant able to cure Lysimachus, which has since 
been called LysimacMa, because it effectually cured this friend 
of the king. When Alexander had a quantity of plants 
brought, among which he recognized that which he had seen 
in his dream, if unfortunately he had not had a sufficient idea 
of it to recognize it and had needed as Nebuchadnezzar a 
1 Erdmann and Jacques omit: " en elle luCme." — Tr. 



2(i8 LKIBMTZ'S fKirigi K OF LOCKE [hk. ii 

Daniel to enable him to recall his dream, it is plain that the 
iilea he would have had of it would have been obscure and 
iiniH>rfoct (for it is thus I should prefer to call it rather than 
a»i/i(S(>il), not for want of appositeness in a certain name, for 
there was none, but for want of ax)i)licatiou to the thing, i.e. 
to the plant Avhich was to heal. In this case Alexander would 
be reminded of certain circumstances, but he would have been 
in doubt about others ; and the name serving us to designate 
auythiug makes us, when we fail in the application to names, 
fail ordinarily in regard to the thing which is promised by 
this name.] 

§ 7. Ph. As complex ideas are the most subject to this 
imperfection, it may arise from the fact that the idea is 
composed of too small a number of simple ideas, as is, for 
example, the idea of an animal which has the skin spotted, (a 
term) Avhich is too general, and which does not suffice to dis- 
tinguish the lynx, the leopard, or the panther, which are 
besides distinguished by particular names. 

TJi. [If we were in the condition Adam was in before he 
had given names to the animals, this defect would not cease 
to have place. Yov supposing we knew that among the 
spotted animals there is one Avhich has extraordinarily pene- 
trating sight, but tliat we did not know whether it is a tiger 
or a lynx, or some other species ; it is an imperfection not 
to be able to distinguish it. Thus the question is not so 
much about the name as about that which may give occa- 
sion for it, and which renders the animal worthy of a particu- 
lar name. It thereby appears also tliat the idea of a spotted 
animal is good in itself, and without confusion and obscurity, 
wlien it is to serve only the genus ; but when joined with 
some other idea which is not sufficiently remembered it is 
to designate the species, the complex idea is obscure and 
imperfect.] 

§ 8. Ph. There is an opposite defect when the simple ideas 
which make up the complex idea are sufficient in number, but 
too confused and involved, like some pictures, which appear 
so confused that they must be only the representation of the 
sky covered with clouds, in which case also we could not say 
that there is confusion any more than if it were another pic- 
ture made to imitate that one ; but when we say that this 



en. xxix] ON HUMAN UNDERSTANDING 269 

picture should make us see a portrait, we shall have reason 
to say that it is confused because we cannot say whether 
it is that of a man, or of a monkey, or of a fish, but it may be 
that when we look at it in a cylindrical mirror, the confusion 
will disappear, and that we shall see that it is a Julius Caesar. 
Thus some mental paintings (if I may so express myself) can- 
not be called confused from any way in which the parts are 
joined together ; for whatever these paintings are, they can 
obviously be distinguished from every other, until they are 
ranked under some ordinary name, to which we cannot see 
that they belong any more than to some other name of a 
different signification. 

Th. [This picture whose parts we see distinctly, without 
noticing the result to which they in a certain way point, 
resembles the idea of a heap of stones, which is truly confused 
not only in your sense, but also in mine, so far as we have 
distinctly conceived their number and other properties. If 
there were thirtj^-six of them (for example), we would not 
know, looking at them heaped together without arrangement, 
that they may produce a triangle or indeed a square, as in 
fact they can, because thirty-six is a square as well as a tri- 
angular number. Thus it is that, in looking at a figure of a 
thousand sides, we shall have only a confused idea of it, until 
we know the number of the sides which is the cube of ten. 
The question, then, is not of names but of the distinct proper- 
ties which are to be found in the idea when we have cleared 
up its confusion. And it is sometimes difficult to find the 
key, or the manner of looking at it from a certain point, either 
by the intervention of a certain mirror or glass in order to see 
the purpose of him who has caused the thing.] 

§ 9. Pli. It cannot be denied that there is yet a third defect 
in ideas, which depends in truth upon the bad use of names ; 
it is when our ideas are uncertain or undetermined. Thus 
we may see every day men who, making no difficulty of 
availing themselves of the ordinary words of their mother 
tongue, before they have learned their precise meaning, change 
the idea which they attach to them almost as often as tliey 
use them in their discourse. § 10. Thus we see how much 
names contribute to this denomination of ideas distinct and 
confused, and, without the consideration of distinct names 



270 Li:iL5MTZ'S CKiriQUE OF LOCKE [bk. ii 

understood as signs of distinct things, it will be very difficult 
to s;iy what a confused idea is. 

Th. [I have, however, just explained it without consideriug 
the names, whether in the case where the confusion is under- 
stood with you as what I call obscurity, or in that where it is 
understood in my sense as the defect in the analysis of the 
notion we have. And I have also shown that every obscure 
idea is in fact indeterminate or uncertain, as in the example 
of the spotted animal we have seen, where we know that some- 
thing further must be added to this general notion, without 
clearly remembering it ; so that the first and third defect 
which you have specified come to the same thing. It is, how- 
ever, very true that the abuse of words is a great source 
of errors, for a kind of error in calculating occurs therefrom, 
as if in calculating we did not notice carefully the place of 
the counter, or if we wrote the figures so badly that we could 
not distinguish a 2 from a 7, or if we omitted or changed 
them through inadvertence. This abuse of words consists 
either in not connecting ideas with the whole or in connecting 
them with an imperfect one, of which a part is empty and 
abides so to speak in blank ; and in these two cases there is a 
certain void and surd in the thought which is filled only 
by the name. Or, finally, the defect is in attaching to the 
word different ideas, whether we are uncertain which should 
be chosen, which makes the idea obscure as well as when a 
part of it is surd ; or whether we select them by turns, and 
avail ourselves sometimes of one, sometimes of the other as 
the sense of the same word in one and the same course of 
reasoning in a way capable of causing error, without consider- 
ing that the ideas do not agree. Thus the uncertain thought 
is either void and without idea, or fluctuates between several 
ideas. This does harm whether ^ we wish to designate some 
definite thing or whether we wish to give a word a certain 
sense corresponding either to that of which we have already 
availed ourselves, or to that which others have used, above 
all in ordinary language, common to all, or to the artisans. 
And from this arise an infinite number of vague and vain dis- 
putes in conversation, in lecture-rooms, and in books, which we 

lErdmann and Jacques omit: "soit qu"ou veuille designer quelque eliose 
determinee," the reading of Gerhardt. — Te. 



CH. XXIX] ON HUMAN UNDERSTANDING 271 

may sometimes avoid by distmctioyis, but which most fre- 
quently serve only to confuse the more, by putting in the 
place of a vague and obscure term other terms still more 
vague and obscure, as those often are which the philosophers 
employ in tlieir distinctions, without having good definitions 
of them.] 

§ 12. Ph. If there is any other confusion in ideas, than this 
which has a secret relation to names, this at least casts more 
disorder than any other into the thoughts and discourse of 
men. 

Th. [I agree, but most frequently some notion of the thing 
and the purpose which we have in availing ourselves of 
the name is mixed with it ; as, for exaiBple, Avhen we speak 
of the church, many have in view a government, while others 
think of the truth of the doctrine.] 

Ph. The way to prevent this confusion is constantly to 
apply the same name to a certain mass of simple ideas united 
in a fixed number and into a deterjnined order. But as that 
suits neither the laziness nor the vanity of men, and as it can 
be used only in the discovery and the defence of the truth, 
which is not always the end they propose to themselves, such 
precision is one of the things that is rather to be wished than 
hoped for. The vague application of names to ideas inde- 
terminate, variable, and almost wholly empty (in the surd 
thoughts) is on one side a covering of our ignorance and 
on the other a confusing and embarrassing of others, which 
passes as true learning and as a mark of superiority in point 
of knowledge. 

Th. [The affectation of elegance and wit has further con- 
tributed much to this intricacy of language ; for in order to 
express thoughts beautifully and agreeably we make no diffi- 
culty of giving words in a tropical manner a sense different 
from the ordinary, sometimes more general or more limited, 
which is called synecdoche, sometimes transferred according to 
the relations of things whose names we change, either by 
concurrence in metonymy, or by comparison in metcqfhor, not 
to speak of irony, which makes use of a term in a sense 
directly opposite to its real meaning. Thus these changes are 
named when recognized ; but they are recognized only rarely. 
And in this indeterminateness of language, in which there is 



272 Li;illNnV/S CRITIQUE OF LOCKE [niv. ii 

lacking a kind of law wliicli regulates the meauing of words, 
as there is something in the title of the digests of the Roman 
Law, De Verborum JSigniJicationibus, persons the most judic- 
ious, when they write for ordinary readers, would be deprived 
of that which gives charm and force to their expression if 
they should confine themselves rigorously to the fixed mean- 
ings of terms. They need only take care that their variation 
does not cause any error or false reasoning to spring up. The 
distinction of the ancients between the exoteric,^ i.e. popular, 
and the acroaniatic ^ mode of writing, which belongs to those 
who are occupied in the discovery of truth, has place here. 
And if any one wished to write in mathematical fashion in 
metaphysics or ethics, nothing would prevent him from so 
doing with rigor. Some have professed to do this, and we 
have a promise of mathematical demonstrations outside of 
mathematics ; but it is very rare that they have been success- 
ful. This is, I believe, because they are disgusted with the 
trouble it is necessary to take for a small number of readers 
where they could ask as in Persius : Quis leget Jiaec, and 
replay : Vel duo vel nemo.^ I believe, however, that if they 
would undertake it in the proper way they would not be 
likely to repent it. And I have been tempted to try it.] 

§ 13. Ph. You will agree with me, however, that complex 
ideas may be very clear and distinct in one aspect, and very 
obscure and confused in another. 

Til. [There is no reason to doubt it ; for example, we have 
very distinct ideas of a good part of the solid visible parts 
of the human body, but we have but few of the liquids which 
enter therein.] 

Ph. If a man speaks of a figure of a thousand sides, the 

1 Cf. Leibnitz, De Stilo philos. Nizolii, Gerhardt, Vol. 4, p. 146; Erdmann, 
p. 63. " AcToamatic " (ante, p. 42), from axpoajxa, anything heard, the verb 
axpoaffflai, the regular word for hearing or attending lectures, the adjective 
a/cpoa^ariKos, designed for hearing only, and, when used of the doctrines of 
philosophers, meaning the esoteric, i.e. the doctrines in their most rigorous 
and exact scientific form, their custom being to give these orally to their 
puxjils, while treating them in a more popular, exoteric manner in their writ- 
ings. Such was the method of Plato and of Aristotle, one of whose works is 
called <t>v(TiKr) dicpoacris. Scliaarsclimidt refers to Bernays, Die Dialoge d. Aris- 
totles, p. .SO sq. Berlin, 1863, and Mad\ig, Excursus YII. to his edition of 
Cicero's De Finihus. — Tr. 

^Sat. 1, lines 2, 3.— Tr. 



OH. xxix] ON HUMAN UNDERSTANDING 273 



idea of this figure may be very obscure in his mind, although 
that of the number may be very distinct therein. 

Th. [This example is not in point here ; a regular polygon 
of a thousand sides is known as distinctly as the millenary 
number, because we may discover and demonstrate all kinds 
of truth.] 

Ph. But we do not have a precise idea of a figure of 
a thousand sides, so that we can distinguish it from another, 
which has only nine hundred ninety-nine. 

Th. [This example shows that you here confound the idea 
with the image. If any one places before me a regular poly- 
gon, sight and imagination cannot make me comprehend the 
millenary therein ; I have only a coyifused idea both of the 
figure and of its number, until I distinguish the number by 
counting. But having found it, I know very well the nature 
and the properties of the proposed polygon, as far as they 
are those of the chiliagon, and consequently I have this idea 
of it ; but I cannot have the image of a chiliagon, and it would 
be necessary to have senses and imagination more exquisite 
and better exercised in order to distinguish it thereby from 
a polygon which had one side less. But the knowledge of 
figures no more than that of numbers depends upon the imag- 
ination, although it is of service therein ; and a mathematician 
can know exactly the nature of a nonagon and a decagon, 
because he has the means of making and examining them, 
though he could not discern them at sight. It is true that a 
workman or an engineer, who does not perhaps know their 
nature sufficiently, can have this advantage beyond a great 
geometer that he can discern them by sight only without 
measuring them, as there are some street-porters^ (faqtiins) or 
pedlers, who will state the weight of what they are to carry 
within a pound, in which respect they will surpass the most 
skilful statistician in the world. It is true that ^ this empiri- 
cal knowledge acquired by a long practice may be very useful 
for prompt action, such as an engineer very often needs to 
perform because of the danger to which he is exposed in 
delaying. But this clear image or this feeling which we may 

1 Erdmann and Jacques omit: " faquins on," tlie rearliii.ijof Gerhardt. — Tr. 
- Erdmanu aud Jacques omit: " II est vray que," the reading of Gerhardt. 
— Tr. 



27-t LEIBNITZ'S ClUTIQUE OF LOCKE [bk. ii 

have of a regular decagon or of a weight of ninety-nine pounds 
consists only in a confused idea, since it is of no avail in dis- 
covering the nature and properties of this weight or of this 
regular decagon, which demands a distinct idea. And this 
example conduces to the better understanding of the differ- 
ence of ideas, or rather that of the idea and the image.] 

§ 15.^ Fh. Another example : We are led to believe that we 
have a positive and complete idea of eternity, which is as 
much as to say that there is no part of that duration which 
is not clearly known in our idea ; but, however great may be 
the duration that is represented, as it is a question of an 
extension without limits, there always remains a part of the 
idea beyond what is represented which continues obscure and 
undetermined; and thence it comes that, in discussions and 
reasonings concerning eternity or any other infinite, we are 
apt to involve ourselves in manifest absurdities. 

Th. [This example does not appear to me to square with 
your design either ; but it is very appropriate to mine, which 
is to disabuse you of your notions on this point. For 
the same confusion of the image with the idea reigns here. 
We have a complete or just idea of eternity, since we have a 
definition of it, although we have no image of it. But the 
idea of the infinite is not formed by the composition of parts, 
and the errors which we meet in reasoning upon the infinite 
do not arise from the defect of the image.-] 

§ 16.^ Pit. But is it not true that when we speak of the 
infinite divisibility of matter, although we have clear ideas of 
the division, we have only very obscure and very confused 
ideas of the parts ? "For I ask whether a man taking the 

1 Erdmann and Jacques have § 25. Gerhardt aud Locke, Philos. Works, 
Vol. 1, p. 505 (Bolm's ed.), have § 15.— Tr. 

■^ The difficulties and errors in the discussion of the infinite arise not " from 
the defect of the image" but from the attempt to imagine or picture that 
which can only he thought. We can think the infinite and absolute, but we 
cannot form an adequate image or picture of it. The " confusion of the image 
witli tlie idea," whicli Leibnitz here speaks of, is one of the causes vitiating 
much of the " reasoning upon the infinite " in the history of thought, and 
lying at the basis of all theories, like those of Hamilton, Mansel, and Spencer, 
which maintain the impossibility on man's part of a knowledge of the infinite. 
(Jf. John Caird, An Introduction to the Philos. of Religion, p. 36. New York: 
Macmillan & Co., 1880. — Tr. 

3 So Gerhardt and Locke; Philos. Works (Bohn's ed.), Vol. 1, p. 505; Erd- 
mann has § 18 ; Jacques § 30. — Tr. 



CH. XXX] ON HUMAN UNDERSTANDING 275 

smallest atom of dust he ever saw has any distinct idea 
of the difference between the one hundred thousandth ^ and 
the millionth part of this atom ? 

Th. It is the same qui pro quo of the image for the idea, 
which I am astonished to see so confused. The possession of 
an image of so great a smallness is not at all the question. 
It is impossible according to the present constitution of 
our body, and if we could have it, it would be much the same 
as that of those things which noAV appear to us apperceplible ; 
but in compensation what is now the object of our imagination 
would escape us and become too great to be imagined. Size 
has no images in itself, and those which it has depend only 
upon comparison with the organs and other objects, and it is 
useless here to employ imagination. Thus it appears by all 
that you, sir, have said to me here that you are ingenious 
in devising difficulties without reason, in demanding more 
than is necessary.] 



CHAPTEE XXX 

OF REAL AKD FANTASTICAL IDEAS 

§ 1. Ph. Ideas in relation to things are real or fantastical, 
adequate or inadequate, true or false. By real ideas I under- 
stand those which have a foundation in nature, and which are 
conformed to a real being, to the existence of things, or to 
their archetypes ; otherwise they are fantastic or chimerical. 

Th. [There is a little obscurity in this explication. The 
idea may have a foundation in nature, without being con- 
formed to this foundation, as when we maintain that the per- 
ceptions we have of color and heat do not resemble any orig- 
inal or archetype. An idea is also real when it is possible, 
although no existing being corresponds thereto. Otherwise 
if all the individuals of a species were lost, the idea of the 
species would become chimerical.] 

§ 2. Fh. Simple ideas are all real, for, although [according 
to many] whiteness and coldness are no more in snow than is 
pain, yet their ideas are in us as effects of powers connected 
1 Erdmauu and Jacques read ; "la 10,000iiie et l;i l(K)()nie." — Tit. 



27G LELBNITZ'S CRITIQUE OF LOCKE [uk. ii 

■with external things, and these constant effects serve us in 
distinguishing things as much as if they were exact images of 
that which exists in the things themselves. 

Th. [1 have examined this point above : but it appears 
thereby that you do not always demand a conformity to an 
archetype, and, according to the opinion (which, hoAvever, I do 
not approve) of those who think that God has arbitrarily 
assigned us ideas, destined to mark the qualities of objects 
without any resemblance or even natural relation, there would 
be also in that case less conformity between our ideas and 
the archetypes than there is between the words which we use 
by institution in language and the ideas, or the things them- 
selves. ] 

§ 3. Ph. The mind is passive as regards its simple ideas; 
but the combinations it makes of them to form complex ideas, 
where many simple ideas are comprised under one and the 
same name, have somewhat of the volitional element ; for one 
man admits into the complex ideas he has of gold or of 
justice simple ideas which another does not admit. 

Til. [The mind is, however, active in reference to simple 
ideas when it detaches them one from another to consider 
them separately, — an act which is voluntary as well as the 
combination of many ideas ; whether it is done to call atten- 
tion to a complex idea resulting therein, or whether it is the 
purpose to comprehend them under the name given to the 
combination. And the mind cannot be deceived therein pro- 
vided it does not unite incompatible ideas and provided this 
name is still virginal, so to speak, that is to say, a name to 
which some notion has not already been attached, which might 
cause confusion with that which is newly attached thereto, and 
make arise either impossible notions by joining together what 
cannot take place, or notions superfluous and containing some 
ohreption,^ by joining ideas, one of which may and ought to 
be derived from the other by demonstration.] 

§ 4. Ph. Mixed modes and relations having no other reality 
than that which they have in men^s minds, all that is requisite 
to make these sorts of ideas real is the possibility of existence 
or of compatibility together. 

Th. \_Relations have a reality dependent upon the mind 

1 I.e. Concealment of the truth. — Tr. 



en. xxx] ON HUMAN UNDERSTANDING 277 

like truths ; but not the mind of men, since there is a supreme 
intelligence which determines them all for all time. Mixed 
modes, which are distinct from relations, may be real acci- 
dents. But be they dependent or not dependent upon the 
mind, it suffices for the reality of their ideas that these modes 
be x>ossible or, what is the same thing, distinctly intelligible. 
And for this result it is necessary that their ingredients be 
com2JOSsible, i.e. capable of existing together.] 

§ 5. Ph. But the complex ideas of substances, as they are 
all formed in relation to things existing outside of us, and 
as representative of substances such as really exist, are real 
only so far as they are combinations of simple ideas really 
both united and coexisting in things coexisting without us. 
On the contrary those are chimerical ^ which are composed of 
such collections of simple ideas as have never been really 
united and found together in any substance ; like those which 
form a centaur, a body resembling gold, save in weight, and 
lighter than water, a body similar in relation to the senses, 
but endowed with perception, voluntary movement, etc. 

Th. [If I take in this manner the terms real and chimeri- 
cal otherwise in relation to the ideas of the modes than in 
relation to those which form a substance, I do not see what 
common notion in each case you give to real or chimerical 
ideas ; for the modes are real to you when they are possible, 
and substances have real ideas with you only when they 
are existent. But in desiring to tally with existence, we 
can determine but little whether an idea is chimerical or 
not, because what is possible, although not found in our 
place or time, may have existed formerly or will perhaps 
some day exist, or may indeed be found already present in 
another world, or even in ours without our knowing it, like 
the idea which Democritus had of the Milky Way ^ which the 
telescopes have verified : so that it seems better to say that 
possible ideas only become chimerical when we attach to them 
without foundation the idea of effective existence, as those do 
who promise themselves the philosopher's stone or, as those 

1 Locke lias: " fantastical," P/ii'tos. Works, Yol. 1, p. 510 (Pxiliii's ed.). — 
Til. 

2 Of. Aristotle, Meteorolof/ica. Bk. I., chap. 8, 345a, 25: "Tlie Milky Way 
is the lij^ht of certain stars." Zeller, Die Philos. d. Griech., .'?d ed., Vol. 1, 
p. 724, note 1 ; 5th ed., 18<.)2, I. 2 [Vol. 2] , p. 8<)7, note 8. — Tr. 



278 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

would do who should believe that there had been a nation 
of centaurs. Otherwise in not regulating ourselves by exist- 
ence we shall deviate unnecessarily from the received language, 
which does not allow us to say that he who speaks in winter 
of roses or pinks speaks of a chimera, unless he imagines he is 
able to find them in his garden, as the story is told of Albert 
the Great ^ or of some other pretended Magician.] 



CHAPTER XXXI 

OF ADEQUATE^ AXD IISTADEQUATE IDEAS 

§ 1. Ph. Real ideas are complete when they represent per- 
fectly the originals whence the mind supposes them to be 
taken, which they represent, and to which it refers them. 
Incomplete ideas rej^resent only a part of these originals. 
§ 2. All our simple ideas are complete. The idea of white- 
ness or of sweetness, which is noticed in sugar, is complete, 
because it suffices for this, — that it corresponds entirely to the 
powers that God has put into this body to produce these 
sensations. 

Th. [I see, sir, that you call complete or incomplete ideas 
those which your favorite author calls idecie adoiquatce aut 
inadcequatce ; you might call them 'perfect or imperfect. I 
have sometimes defined idea adcequata (a pe?/eci idea) as that 
which is so distinct that all its ingredients are distinct, and 
such is nearly the idea of a number. But when an idea is 
distinct and contains the definition or the reciprocal marks 
of the object, it may be inadcequata or imperfect, viz. : when 

1 Albertus Magniis, 119.3-1280. Scliaarschmidt states that " like many other 
scholars of those dark centuries (Michael Scotus, Roger Bacon, etc.) he was 
suspected of Magic," and adds that " Trithemius in particular, who, moreover, 
takes the philosopher into his protection, gives an account thereof in his An- 
nales Hirsaugienaes, Vol. 2, p. 40. Naude in his Apologie des Grands Hommes 
Soupconnes de Mac/ie, chap. 18, Bayle in his Bictionary, sSe under Albert 
Le Grand, and Brucker. Hist. PhUosophife, 3, 793 sq., have likewise defended 
him." On his life and philosophy, cf. Erdmann, Gruridrlss d. Gesch. d. 
Philos.^^ 199-202, Vol. 1, pp. 356 s^., and English translation of same; also 
Stockl, Gesch. d. Philos. d. MitUdalters, Vol. 2,"^pp. 3.52 sq., §§ 101-119. — Tr. 

^Locke's title; the French might be rendered " complete and incomplete," 
as in the text. — Tb. 



CH. XXXI] ON HUMAN UNDERSTANDING 279 

these marks or these ingredients are not also all distinctly 
known ; for example, gold is a metal which resists the cupel 
and aqua fortis ; it is a distinct idea, for it gives the marks 
or the definition of gold; but it is not perfect for the nature 
of cupellation and the working of aqua fortis is not sufficiently 
known to us. Whence it comes that, when there is only an 
imperfect idea, the same subject is susceptible of many defini- 
tions independent the one of the other, so that we cannot 
always derive one from the other nor see beforehand that they 
must belong to one and the same subject, and then experience 
alone teaches us that they all belong to it at once. Thus gold 
may still be defined as the heaviest of our bodies, or the most 
malleable, without speaking of other definitions which might 
be invented. But we shall be able to see why it belongs 
to the heaviest of metals to resist these two tests of the assay- 
ers only when men shall have penetrated farther into the 
nature of things ; whilst in geometry, where we have perfect 
ideas, the case is different, for we can prove that the sec- 
tions of the cone and of the cylinder, made by a plane, are the 
same, viz. ellipses, and this cannot be unknown to us, if we 
take notice of it, because the notions we have of them are 
perfect. With me the division of ideas into perfect and im- 
perfect is only a sub-division of distinct ideas, and it appears 
to me that only the confused ideas, like that we have of sweet- 
ness, of which you, sir, speak, deserve this name ; for although 
they express the power which produces the sensation, they 
do not express it wholly, or at least we cannot know this, for 
if we comprehended what is in this idea of sweetness we have 
we could judge whether it is sufficient as a rational expression 
of all that experience causes us to notice therein.] 

§ 3. Fh. From simple ideas let us come to the complex; 
they are either of modes or of substances. Those of modes 
are the voluntary collections of simple ideas which the mind 
puts together without regard to certain archetypes or real and 
actually existing models ; they are complete and cannot be 
otherwise, because not being copies but archetypes, which the 
mind forms in order to avail itself of them in laiiking things 
under certain denominations, they can lack nothing, because 
each includes such a combination of ideas as the ndnd has 
desired to form, and consequently such perfection as it had 



280 LEIBMTZ'S CIIITIQUE OF LOCKE [bk. ii 

})liuiiied to give thereto, and we cannot conceive that the 
understanding of any one can have a more complete or more 
perfect idea of a triangle than that of a figure of three sides 
and three angles. He who put together the ideas of danger, 
of execution, of the trouble that fear produces, of a calm con- 
sideration of what it would be reasonable to do, and of an 
actual application to its execution without being frightened 
by the danger, formed the idea of courage, and had what he 
desired, viz. : a complete idea conformed to his good pleasure. 
It is otherwise in our ideas of substances in which we main- 
tain that which really exists. 

Th. [The idea of triangle or of courage has its archet3qDe in 
the possibility of things as well as the idea of gold. And it is 
a matter of indifference, so far as the nature of the idea 
is concerned, whether it was invented in advance of experi- 
ence, or whether it was retained after the perception of a 
combination which nature had made. Combination also, 
which produces the modes, is not wholly voluntary or arbi- 
trary, for we can put together what is incompatible, as those 
do who invent machines for perpetual motion, while others 
can invent those which are good and practicable which have 
no other archetypes with us than the idea of the inventor 
which has as its archetype the possibility of things or the 
divine idea. Now these machines are substances. We can 
also invent impossible modes, as "uhen we maintain the 
parallelism of parabolas, by imagining that we can find two 
parabolas parallel to each other, like two straight lines or 
two circles. An idea, then, whether it be that of a mode, or 
that of a substance, may be complete or incomplete according 
as we understand well or ill the partial ideas which form the 
total idea : and it is a mark of a perfect idea when it makes 
known perfectly the possibility of the object.] 



cii. xxxiii] ON HUMAN UNDERSTANDING 281 



CHAPTER XXXII 

OF TRUE AND FALSE IDEAS 

§ 1. Ph. As truth ^ or falsehood belongs only to proposi- 
tions,^ it follows that when ideas are termed true or false 
there is some tacit proposition or affirmation; § 3. or a tacit 
assumption of their conformity to something, § 5. above all 
with what others designate by this name (as when they speak 
of justice) item to what really exists (as man exists but not 
the centaur) item to the essence, upon which depend the prop- 
erties of the thing ; and in this sense our ordinary ideas of 
substances are false when we think of certain substantial 
forms. Besides, ideas deserve rather to be called accurate 
or faulty, than true or false. 

Th. I believe that true or false ideas might be so under- 
stood, but as these different senses do not agree between them- 
selves and cannot be conveniently ranked under a common 
notion, I prefer to call the ideas true or false in relation to 
another tacit affirmation which they all include, which is that 
of possibility. Thus possible ideas are trxie, impossible /aZse.] 



CHAPTER XXXIII 

OF THE ASSOCIATION OF IDEAS 

§ 1. Ph. We often notice something odd in the reasonings 
of people, and everybody is subject to this. § 2. It is not 
alone obstinacy or self-love ; for often people who are well 
disposed are guilty of this fault. It does not indeed suffice to 

1 Cf. Nev) Essays, Bk. IV., chap. 5. — Tr. 

2 Cf. Aristotle De Anima, III. 0,430'^, 27, and E. Wallace, Aristotle's Psychol- 
Of/y in Greek and English, loith Introduction and Notes, pp. KiO, 101, Cam- 
bridge: University Press, 1882; also De Interj)ret. 1, Ki'', 12, and E. Wallace, 
Outlines of the Philos. of Aristotle, .3d ed., § 11, p. 27. For Leibnitz, tbe true 
is the thinkable, i.e. that whicli is free from contradiction in itself and of 
other truth. Thought-necessity is his criterion of possibility and of truth. — 
Tr. 



282 LEIBNITZ'S CRITIQUE OF LOCKE [bk. n 



attribute it to education and to prejudice. § 4. It is rather 
a kind of madness, and Ave should be foolish if we should 
always act thus. § 5. This fault arises from a non-natural 
connection of ideas, which has its origin in chance or custom. 
§ 6. Inclination and interest enter into it. Certain tracts of 
the repeated course of animal spirits become beaten roads ; 
Avhen we know ^ a certain air, we find it as soon as we begin 
it. § 7. Thence arise the sympathies or antipathies which 
are not born with us. A child has eaten too much honey and 
has been surfeited by it, and then having become a full-grown 
man, he cannot hear the name honey without a rising of the 
stomach. § 8. Children are very susceptible to these impres- 
sions, and it is well to be careful of them. § 9. This irregu- 
lar association of ideas has a great influence in all our actions 
and passions natural and moral. § 10. Darkness revives the 
idea of ghosts in children because of the stories told them 
about them. § 11. You do not think of a man whom you 
hate without thinking of the evil he has done or may do. 
§ 12. You shun the room in which you have seen a friend die. 
§ 13. A mother w^ho has lost a very dear child sometimes 
loses with it all her joy, until time effaces the impression 
of this idea, which sometimes never ^ happens. § 14. A man 
perfectly cured of madness by an extremely painful operation 
acknowledged all his life his obligation to the one who per- 
formed this operation ; but it was impossible for him to 
endure the sight of the operator. § 15. Some hate books all 
their life because of the bad treatment they received in school. 
Some one having once gotten the upper hand of another upon 
some occasion keeps it always. § 16. A man was found 
who had learned to dance finely, but could not execute the 
dance unless there was in the room a trunk like the one 
which had been in the room where he had learned. § 17. 
The same non-natural bond is found in the intellectual habits ; 
you bind matter to being, as if there were nothing immaterial. 
§ 18. The sectarian party in philosophy, religion, and the 
state is attached to its opinions. 

Th. [This remark is important and wholly to my taste, and 
can be fortified by an infinite number of examples. Descartes 

1 Gerhardt reads: "salt"; Erdmann and .Jacques: "suit," follow. — Tr. 

2 Gerhardt reads : "jamais"; Erdmann and Jacques : "pas." — Tr. 



CH. xxxiri] ON HUMAN UNDERSTANDING 283 

having had in his youth some affection for a squint-eyed per- 
son could not prevent himself from having all his life an incli- 
nation towards those who had this defect. Hobbes, another 
great philosopher, could not (they say) remain alone in a 
dark place, without having his mind frightened by images of 
ghosts, although he did not believe in them, this impression 
having remained from the stories told to children. Many 
persons well informed and sensible, and who are decidedly 
superior to superstition, cannot bring themselves to be thir- 
teen at a repast without being extremely disconcerted, having 
sometime been impressed by the fancy that one of them must 
die during the year. There was a gentleman who, having 
been injured, perhaps in his infancy, by a badly fastened pin, 
could not see one in this condition without being ready to fall 
into a swoon. A prime minister, who bore in the court of his 
master the name of President, was offended by the title of the 
book of Ottavio Pisani, called Lycurgus, and wrote against this 
book, because the author, in speaking of the officers of justice 
whom he thought superfluous, had named also the Presidents, 
and although this term in the person of this minister meant a 
totally different thing, he had so attached the word to his 
person that he was wounded in this word. And this is a case 
of the most usual of the non-natural associations, capable of 
misleading, as those of words to things, when indeed there is 
any ambiguity. In order the better to understand the source 
of the non-natural bond of ideas, you must consider what I 
have already said above (Chap. 11, § 11^), in speaking of the 
reasonings of animals, that man as well as the animal is 
inclined to put together in his memory and imagination what 
he has observed united in his perceptions and experience. It 
is in this that all the reasoning, if so it may be called, of 
animals consists, and often that of men, so far as they are 
empirical and govern themselves only by the senses and 
examples, without examining whether the same reason still 
has force. And as often the reasons are unknown to us, we must 
have regard to the examples in proportion to their frequency, 
for then the expectation or the reminiscence of one perception 

1 Of. ante, p. 145. Gerhardt has § 1 ; Erdmaiiii aiul Ja<!ques § 11 ; the latter 
reference is the correct one, and has therefore been phiced in the text of the 
translation. — Tk. 



284 LEIBNITZ'S CRITIQUE OF LOCKE [bk. ii 

on the occasion' of another perception which is ordinarily 
connected therewith is reasonable ; particularly when the 
question is about taking precautions. But as the vehemence 
of a very strong impression often produces as much effect 
at once as the frequency and repetition of many moderate 
impressions would be able to make in a long time, it happens 
that this vehemence engraves upon the fancy an image as 
profound and as vivid as long experience.^ Whence it comes 
that a chance but violent impression unites in our imagination 
and memory two ideas, at that time together there,^ altogether 
as strongly and durably and gives us the same inclination to 
connect them and to attend to them one after the other, as if a 
long usage had verified the connection ; thus the same result 
of association is found, although the same reason does not 
exist. Authority, party,'* custom, produce also the same effect 
as experience and reason, and it is not easy to deliver one's 
self from these inclinations. But it would not be very 
difficult to keep one's self from being deceived in these judg- 
ments, if men would attach themselves seriously enough to 
the search for truth, or proceed methodically, when they 
recognize that it is important to them to find it.] 

1 Gerhardt reads: "d'une perception a I'occasion," which Erdmann and 
Jacques omit. — Tr. 

2 Erdmann and Jacques add : " auroit pu le faire," could have done. — Tr. 

3 Gerhardt reads : " qui y estoient ensemble alors, tout aussi fortement et 
durableraeut; et nous donue," etc. Erdmann and Jacques, " qui deja y 
e'taient ensemble, et nous donne," etc. — Tr. 

* Erdmann and Jacques omit : " le parti." — Tr, 



NEW ESSAYS ON HUMAN UNDERSTANDING 



Book 111. — Words 
CHAPTER I 

OF WORDS OR LANGUAGE IN GENERAL 

§ 1. Ph. God having made man to be a social being, has not 
only inspired him with the desire, and placed him under the 
necessity of living with those of his species, but has given 
him also the faculty of speech which is to be the great instru- 
ment and common bond of this society. Hence it is that 
words arise, which serve to represent and also to explain 
ideas. 

Th. [T rejoice to see that you are averse to the view of 
Hobbes,^ who did not admit that man was made for society, 

1 Thomas Hobbes, 1588-1679, in his De Cive, 1642, and Leviathan, 1051, 
maintained that man, being by nature a selfish and solitary animal, had no 
natural impulse for society, and that social union sprang simply from fear 
and from motives of gain, the natural condition being that of universal war. 
Leibnitz maintains, in agreement with Aristotle and Hugo Grotius, 1583-1645, 
that Nature herself has destined man for society in order not only that he 
may the better and more easily realize his highest being, but that he may 
realize it at all, such realization being impossible in isolation and solitude. 

Cf. Aristotle, Polit. I., 2, 1253^, 2: on tmv (|>uo-ei 17 n-dAis icni, Kai on ovSpooTTOs (f)ii<Tfi. 
TToAiTi/cbi' fuSoi'; III., 6, 1278*^, 19: <j>v<Tei. fxev eariv avepM^o:; fuoi/ TroAtTiKor, Sio Kai 
Ix-qSev Seofj.ei'oi rfj? Trap' aAAijAoii' PorjOeia^ ovk eXarrov opiyoi'Tai toC o-kcTt"', English trans- 
lation by B. Jowett, Vol. 1, pp. 4, 78, Oxford: Clarendon Press, 1885; also FAh. 

NiC. IX., 9, 1169'^, 3 sq., espec. 16-19: arouov 6' itroj? Kai t6 fioi'tiirrtv TTOieij' Toi' 
lxa.Ka.pioV oiifle'i? yap cAoit' af KaB' avTov Ta ttolvt' exeiv ayada.' ttoAitikoi' yap o ai'Bponro^ 

Ka.\ a-v^^v ne<l>vK6^^ J., 1, 1094*', 6 sq., English translation by F. H. Peters, pp. 307 
sq.,3; cf. also Zeller, Philos. d. Grieclu, II., 2 [Vol. 4], pp'. 680, ()62, 3d ed., 1879. 
Grotius, De, Jure Belli et Pan's, 1625, Preliminary Discourse, § 6: "Amongst 
the things peculiar to man, is his desire of society, that is, a certain inclination 
to live with those of his own kind, not in any manner whatever, but peace- 

285 



280 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

conceiving that he has been forced into it by necessity and by 
the wickedness of those of his species. But he did not con- 
sider that the best men, free from all wickedness, united them- 
selves the better to obtain their purposes, as the birds flock 
together the better to travel in company, and the beavers unite 
in large numbers to make great dams, in which work a small 
number of these animals could not succeed ; and these dams 
are necessary to them, to provide reservoirs of water or little 
lakes, in which they build their huts and catch the fish upon 
which they feed. This then is the foundation of the society 
of the animals which are adapted to it, and nowise the fear of 
their kind, which is rarely found among animals.] 

Ph. Very true, and it is the better to cultivate this society 
that man by nature has his organs so fashioned that they are 
adapted to the formation of the articulate sounds which we 
call tvords. 

Th. [As for organs, monkeys have them apparently as suit- 
able as ours for the formation of words, but they do not take 
the least step in this direction.^ Thus it must be that they 
lack an invisible something. We must also consider that we 

ably, and in a community re.arnlated according to the best of his understand- 
ing, which disposition the Stoicks termed olKeioxrt? " ; quoted from English 
translation with "all the large notes of Mr. J. Barbeyrac," etc., London: 
Printed for W. Innj-s and R. Manby, and others, 1738. A French translation 
by Jean Barbeyrac, professor of law at Grouingen, "with the author's notes 
which had not 3-et appeared in French, and new notes by the translator," 

2 vols., 4to, Amsterdam, 1724; a later translation into English by Whewell, 

3 vols., 8vo, Cambridge, 1853 ; a German translation in J. H. v. Kirchmaun's 
Philos. Bibliothek, 3 vols., 12mo, Leipzig, 1879. 

In the formation of society, language — Adyo?, rational speech — plays an 
important part, serving as a special means of communication between men. 
Cf. Aristotle, Polit.l., 2-18, 1253''; Grotius, De Jure Belli et Pads, Prelim. 
Disc. § 7: "A man grown up . . . has besides an exquisite desire of society, 
for the satisfaction of which he alone of all animals has received from nature 
a peculiar instrument, viz. the use of speech." — Tr. 

1 Schaarschmidt states that "this earlier generally diffused view, that the 
apes had organs of speech — an opinion still at the present day firmly held by 
the negroes — has already been refuted by Peter Camper," 1722-1789, a dis- 
tinguished Dutch anatomist and naturalist, in his Natuurkxindige Verhand- 
elingen or-er den Oranrf-Outanf/ an eenirfe nndere Aapsoorten ; cf. p. 147 s<]., 
of the German translation by J. F. M. Herbell. Diisseldorf, 1791, 4to. The 
most important of Camper's works bearing on comparative anatomy, trans- 
lated into French Ijy H. C. Jansen, were published in CEwres de P. Camper 
qui ont pour objet I'hiMoire naturelle, la phi/siolor/ie, et FaJiatoitiie compar^e. 
Paris, 1803, 3 vols., 8vo. The piece referred to in this note is found in Vol. 1 
of thised. — Tr. 



CH. I] ON HUMAN UNDERSTANDING 287 

could sjyeak, i.e. make ourselves understood by the sounds of 
the mouth without forming articulate sounds, if we availed 
ourselves of musical tones for this effect ; but more art would 
be necessary to invent a language of tones, whilst that of 
ivords may have been formed and perfected gradually by per- 
sons who found themselves in a state of natural simplicity. 
There are, however, people like the Chinese, who by means of 
tones and accents vary their words, of which they have only a 
small number. Thus it was the opinion of Golius,^ a cele- 
brated mathematician and great linguist, that their language is 
artiiicial, i.e. had been invented all at once by some clever man 
in order to establish verbal intercourse between the large num- 
ber of different nations inhabiting this great country which 
we call China, although this language may now be found 
altered by long use.] 

§ 2. Ph. [As orang-outangs and other monkeys have organs 
without forming words, we can say that parrots and some 
other birds have words without language], for we can train 
these birds and many others to form sounds quite distinct ; 
but they are nowise capable of language. Man only is in a 
condition to avail himself of these sounds as signs of internal 
conceptions, in order that thereby they may be manifested to 
others. 

Th. [I believe in fact that apart from the desire of making 
ourselves understood we should never have formed language ; 
but being formed, it further serves man in reasoning within 
himself, both by the means words give him of remembering 
his abstract thoughts, and the benefit he finds in availing him- 
self in reasoning of characters and surd thoughts ; for he 
would require too much time, if he were obliged to explain 
everything and always to substitute definitions in the place of 
terms.] 

§ 3. Ph. But as the multiplication of words would produce 

1 Jacob Gobi — Latin, Golius — 159f)-lG()7, an eminent Dutch orientalist, 
who distinguislied himself at Leydeu University in classics, matliomatii^s, and 
philosophy, was a pujiil of Erpenius in Arabic, and in Ki'i-l succeeded him as 
professor of Arabic at Leyden. In 1629 he returned from Asia Minor and tlie 
East, where he had spent four years, brinj,nn,i>; witli him a largo and valuable 
collection of Mss. which he placed in the liljrary of the university. His prin- 
cipal work, still to-day esteemed, is the Lexicon Arabieo-Latinam, 1U53, 
folio. — Tu. 



288 LEIBNITZ'S CRITIQUE OF LOCKE [uk. 



confusion in tlieir use, if a distinct term were necessary to 
designate each particular thing, hxnguage has been further 
perfected by the use of general terms when they signify general 
ideas. 

Th. [^General terms serve not only for the perfection of 
languages, but they are necessary even to their essential 
constitution. For if hj particular things we mean individual 
things, it would be impossible to speak if there were only 
proper names and not appellatives, i.e. if there were words 
only for the individuals, since at every moment something 
now presents itself (to the mind) when individuals, accidents, 
and particularly acts, which are most frequently designated, 
are in question. But if by particular things we understand 
the lowest species {species infimce), besides the fact that it is 
difficult very often to determine them, it is manifest that they 
are already universals formed upon similitude. Then as the 
question is only of a similitude more or less extended, accord- 
ing as we speak of genera or species, it is natural to indicate 
every sort of similitude or agreement and consequently to 
employ general terms of all degrees ; and indeed the most 
general being less burdened with relation to the ideas or 
esselices they include, although they are more comprehensive 
in relation to the individuals to which they apply, were very 
often the easiest to form and are the most useful. Thus you 
see that children and those who know only little of the lan- 
guage which they wish to speak, or of the matter of which 
they speak, avail themselves of general terms as thing, plant, 
animal, instead of employing the proper terms which they lack. 
And it is certain that all proper or individual names were 
originally appellative or general.^] 

1 Leibnitz seems here to be in error in deciding from a logical or meta- 
physical point of view that language originated in or proceeded from general 
terms and relations rather than in those which are individual. In the order 
of experience the individual thing or relation is first, and first receives its 
name either wholly arbitrarily or by convention, or by this in combination 
with natural imitation or suggestion ; the generalizing process and its result, 
the general name or term, comes afterwards. Children, it is true, use terms 
of general import, but with no consciousness that they are general. Every- 
thing is for them individual, particular, separate and by itself until continued 
observation and increasing knowledge enable them to detect similarities and 
differences and to classify and generalize accordingly. Then only do they, 
strictly speaking, possess or use general terms. ^Tr. 



CH. I] ON HUMAN UNDERSTANDING 289 

§ 4. Ph. There are also words which men employ not to 
signify an idea, but the lack or absence of a certain idea, as 
nothing, ignorance, sterility. 

Th. [I do not see why we could not say that there are 
privative ideas, as there are negative truths, for the act of 
denial is positive. I had already touched upon this.] 

§ 5. Ph. Without disputing about this point, it will be more 
useful to approach a little nearer the origin of all our notions 
and knowledge, to observe how the words employed to form 
actions and notions wholly removed from the senses, derive 
their origin from sensible ideas, whence they are transferred 
to significations more abstruse. 

Th. [The fact is our needs have compelled us to leave the 
natural order of ideas, for this order would be the same for 
angels, men, and all intelligences in general, and would have to 
be followed by us, if we had no regard for our interests. It 
has been necessary to attach thereto what the occasions and 
accidents to which our species is subject have furnished us ; 
and this order gives not the origin of the notions, but so to speak 
the history of our discoveries.^'\ 

Ph. [Very true, and it is the analysis of Avords which may 
teach us by means of the names themselves this concatenation 
which that of the notions cannot give by means of the reason, 
which you have brought forward.] Thus the following words : 
imagine, comprehend, to attach, conceive, instil, disgust, trouble, 
tranquillity, etc., are all derived from the operations of sensible 
things and applied to certain modes of thought. The word 
spirit in its primary signification is breath,^ and angel signifies 
a messenger. Whence we can conjecture what kind of notions 

1 "The natural order of ideas," according to Leibnitz, proceeds from the 
general to the particular, from the abstract to the concrete, while language 
shows that "we have advanced from sense-impressions to abstract ideas," 
and thus " expresses not the essence of our knowledge, but only the history of 
its development. In a still broader sense the history of language is the history 
of the development of the human spirit in general." — -Tr. 

2 Cf. the Hebrew 111"! (Spinoza, Tract. Theol. Polit., chap. 1, Opera, ed. Van 
Vloten and Land, Vol. 1, p. 384; English translation by Elwes, Vol. 1, p. 19) ; 
the Greek nvedixa from nvelv (Cremer, Bib. Theol. Lexicon of N. T. Greek, 2d 
English from 2d German ed., p. 504, Edinburgh: T. and T. Clark, 1878, says 
that as " the element of life " ..." in a physiolof/ical sense, wo often find it 
(' TTveviJ.a') in profaTie Greek, especially in the poets and in later Greek; in a 
psychological sense, as the element of human existence and personal life, 
never") ; and the Latin spiritus from spirare. — Tn. 

U 



290 LEIBNITZ'S CRITIQUE OF LOCKE [hk. hi 

they had who spoke these first languages and how nature will 
suggest unexpectedly to men the origin and the principle of all 
their knowledge by the terms themselves. 

Th. [I have already remarked to you that in the credo of 
the Hottentots they called the Holy Spirit by a term which 
signifies among them a breath of air benign and sweet.-^ The 
same is true as regards the majority of other words, and indeed 
the fact is not always recognized because most frequently the 
true etymologies are lost. A certain Dutchman, with little 
regard for religion, abused this truth (that the terms theology, 
ethics, and metaphysics are taken originally from gross things) 
in order to ridicule theology and the Christian faith in a little 
Flemish dictionary, in which he gave to the terms definitions 
or explications not such as usage demands, but such as the 
original force of the words seemed to bear, and put upon them 
a malicious interpretation ; and as he elsewhere had given 
indications of impiety he is said to have been punished in the 
Raspel-huys? It will, however, be well to consider tliis analogy 
of sensible and non-sensible things which has served as the basis 
of tropes : a matter that you will understand the better by con- 
sidering a very extended example such as is furnished by the 
use oi prepositions, like to, toith, from, before, in, without, by, for, 
upon, toivards (d, avec, de, devant, en, hors, par, pour, sur, vers), 
which are all derived from place, from distance, and from 
motion, and afterwards transferred to every sort of change, 
order, sequence, difference, agreement. To ((>) signifies 
approach, as in the expression : I go ^o (a) Rome. But as in 
order to attach anything we bring it near that to which we 
wish to unite it, we say that one thing is attached to (d) 
another. And further, as there is, so to speak, an immaterial 
attachment, when one thing follows the other from moral 
reasons ; we say that what follows the movements and voli- 
tions of any one belongs to (d) that person or adheres to him 
as if it gave signs to this person to go near it or with it. A 

1 Cf. Book I., chap. 3, § 8, Th. The Apostle's Creed, the Ten Command- 
ments, and the Lord's Prayer in the Hottentot language, as sent to Leibnitz 
by N. Witsen, are given in Dutens, Leihnit. opera omnia. Vol. 6, Pt. 2, pp. 
2(M-206. Schaarschmidt remarks that " this observation of both philosophers, 
that the meaning of words has proceeded and still proceeds from the concrete 
to the abstract, is the guide to sound etymology and word-explanation." — Tk. 

2 Erdmaun and Jacques have ; " Raspel-huyss." — Tii. 



CH. II] ON HUMAN UNDERSTANDING 291 

body is with (avec) another when they are in the same place; 
bnt they say also that a thing is with [avec) that which is found 
in the same time, in the same order, or part of an order, or 
which concurs in one and the same act. When we come fro7n 
(cle) any place, the place has been our object through the 
sensible things it has furnished us, and it is still in our 
memory, which is entirely filled with it; and thence it comes, 
that the object is signified by the preposition of (de) as in the 
expression, the question is of (cle) that, they speak of (de) 
that, i.e. as if it arose from it. And as what is included in 
any place or in any whole is supported by and carried away 
with it, the accidents are in the same way considered as in 
(dans) the subject, sunt in subjecto, inhmrent subjecto. The 
particle tqjon (sur) is also applied to the object; they say he 
is iq)07i (sur) this matter, very much as a workman is iipoji 
(sur) the wood or U2wn (stir) the stone, that he cuts or forms; 
and as these analogies are extremely variable and do not de- 
pend on any determinate notions, it thence comes that 
langiiages vary much in the use of these particles and cases 
which the prepositions govern, or rather in which they are 
found as things understood and virtually included.] 



CHAPTER II 

ON THE SIGNIFICATION OF WORDS 

§ 1. Ph. Now as words are employed by men as signs of 
their ideas, we may ask in the first place how their words have 
been determined ; and we find that it is not by any natural 
connection existing between certain articulate sounds and cer- 
tain ideas (for in this case there would be only one language 
among men), but by an arbitrary institution in virtue of which 
a given word has been purposely made a sign of a given idea.^ 

1 For early discussions of the nature and origin of language, and tlic ques- 
tion whether words were given by nature or convention, (/. Flato, Cnili/liis, 
English translation by B. Jowett, The Dialoijnes of Plato, 2d cd., 1875, Vol. 2, 
p. 20:'..sf/. ; .3d ed., 1892, Vol.1, p. 323 sq., New York: Macmillan &Co.; Aristo- 
tle, Dtt Interpret., 2, 16'', 19 sq.; E. Wallace, Outline.^ of the I'/tilos. of Aris- 
totle, 3d ed., § 11, p. 27. For modern discussions, cf. W. D. Whitney, Lawjuarje 



292 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

Th. [I know it has been customary to say in the schools 
and almost everywhere else that the meanings of words are 
arbitrary {ex instituto) and it is true that they are not deter- 
mined by a natural necessity, but they are nevertheless 
determined by reasons sometimes natural, in which chance has 
some share, sometimes moral, where choice enters. There are 
perhaps some artificial languages which are wholly of choice 
and entirely arbitrary, as that of China is believed to have 
been, or as those of George Dalgarno ^ and the late Mr. Wil- 
kins,' bishop of Chester. But those which are known to have 
been coined from languages already known, are from choice 
mixed with what there is of nature and chance in the lan- 
guages they suppose. Thus it is in the case of those languages 
which thieves have coined in order to be understood only by 
those of their gang, which the Germans call Hothicelsch,^ the 

and the Study of Language, Lect. XI., p. 395 sq., 4th ed., New York, 1869; 
B. Jowett, in his Introduction to Plato's Cratylus, op. cit., 2d ed., Vol. 2, p. 189 
sq.; 3d ed., Vol. 1, p. 281 sq. ; H. Steiuthal, Einleitung in die Psychologic und 
Sp)rtchicissenschaft ; Herm. Paul, Principien der Sprachgeschichte , Halle, 
1880; B. Delbriick, Einleitung in das Sprachstudium, Leipsic, 1880, 2d ed., 
1884. Leibnitz rightly points out that both nature and freedom of choice 
share in the formation of language. " Nature furnishes to a certain extent 
the material which the mind in its progressive self-absorption shapes within 
certain limits arbitrarily; and every human individual in the use of the 
language already formed is himself still so situated as to be able up to a 
certain point freely to ajipropriate and use that which is given." — Tr. 

1 George Dalgarno, c. 1626-1687, published at London in 1661, his Ars sig- 
norum, vulgo character universalis et lingua philosophica. Qua poterunt, 
homines diversissimorum idiomatum, spatio duarum septimanarum, omnia 
animi sua sensa (in rebus familiarihus) non minus intelligihiliter, sive scri- 
bendo, sive loquendo, mntuo communicare, quam Unguis j^ropiis vernaculis, 
from which Bishop John Wilkins, 1614-1672, derived the idea of his Essay 
towards a real character and a philosophical language ivith an alphabetical 
dictionary. London, 1668. For Leibnitz's plan of a General Characteristic 
{Characteristica Universalis — Sp^cieuse generale) and the extent to which 
he followed Dalgarno and Wilkins, cf. Trendelenburg's paper : Ueber Leibni- 
zens Entivurf einer allgemeinen Charakteristik, in his Historische Beitrcige 
zur Philos., Vol. 3, p. 1 sq., Berlin, 1867 ; cf. also Gerhardt, Die philos. Schrift. 
V. G. W. Leibniz, Vol. 7, p. 3sg. ,■ Vol. 3, p. 216; Duteus, Leibnit. opera omnia, 
Vol. 6, p. 262. Dalgarno is credited with the invention of the first manual 
alphabet. His works were reprinted at Edinburgh, 18:34, 4to. — Tr. 

2 Cf. Ave' Lallemant, Das deutsche Gaunerihum, 4 vols., Leipzig, 1858-1862, 
in which, says Schaarschmidt, "the so-called Rothwalsch, the artificial lan- 
guage of thieves in Germany, prominent already in the sixteenth and more so 
in the seventeenth century, is treated with especial thoroughness of detail. 
In this work it is shown that the Hebrew especially has contributed to the 
Gaunersprache a strong word-contingent, while its grammar is conformed to 



CH. II] ON HUMAN UNDERSTANDING 293 

Italians Lingua Zerga,^ the French Narquois, but which they 
usually form upon (the basis of) the languages commonly 
known to them, either by changing the received significations 
of the words by means of metaphors, or by making new words 
by means of a composition or derivation in their own fashion. 
Languages are also formed through the intercourse of different 
peoples, either by mingling indifferently neighboring lan- 
guages, or as most frequently happens, by taking the one as a 
base which is mutilated and altered, mixed and corrupted by 
neglecting and changing that which it observes, and even by 
grafting thereupon new words. The Lingua Franca, which is 
used in the commerce of the Mediterranean, is made from 
the Italian, and no regard is paid to the rules of grammar. 
An Armenian Dominican, with whom I conversed at Paris, 
had himself made, or perhaps learned from his fellows, a kind 
of Lingua Franca, made from Latin, which I found intelligible 
enough, although it had neither case, nor tense, nor other 
inflections, and he spoke it with ease, being accustomed to it. 
Father Labb^,- a French Jesuit, very learned, known by many 
other works, has made a language of which Latin is the base, 
which is easier and has less constraint than our Latin, but 
which is more regular than the Lingua Franca. He has made 
a book expressly of it. As for the languages which are found 
made a long time ago, there are but few which are not greatly 

the German. In Italy the Gaunersprache bears the name Gergo, whi(!h corre- 
sponds to the French Argot. To what extent in Leibnitz's time attention was 
directed to the Rothwiilsch the romance literature shows ; but especially the 
Gcsichte I'hiktnders von Sitteivald," a remarkable work, in which, under the 
name of Philander von Sittenwald, the author. Job. Mich. Moscherosch, KiOO- 
1()(J9, a German litterateur, whose true name was Kall)kopf , has given a series 
of satirical pictures of the caprices and the vices of society in his time, and 
which placed him among the best prose writers of his century. It was jjub- 
lished at Strasburg, 1044-1650, 2 vols., 8vo. — Tr. 

1 Erdmann and Jacques read : " Gergo." — Tr. 

2 Philip Labljc, KiOT-KJiiT, a learned French chronologer, a man of vast 
memory, astonishing erudition, and great mental activity ; a voluminous 
writer, and though gentle in personal character, a fierce and abusive contro- 
versialist. Leibnitz mentions him in a letter, July 15, 17011, to Geheimrath 
von Ilgen; cf. Gerhardt, Leibniz. phUos. Schrift.,1, 3(i: " iioch des P. Labl)e' 
(der die Lateinische mittelst einiger Veranderungen zur allgemeinen Spracli 
machen wollen)." He was the author of Concordia chronnlor/ira, technica ct 
luatorira, lf!5(); but is chiefly known to-day by liis work on Latin pronuncia- 
tion, Eriiditip, promintintinnis catholici indices, enlarged by E. Leeds, and 
republished in London, 1751. — Ti'.. 



291 LEIBNITZ'S CKiTlQUE UF LOCKE [uk. 



iiltered to-day. This is evident by comparing them with their 
ancient books and monuments wliich remain. The old French 
approached nearer the Proven9al and the Italian, and we see 
the Theotisque * Avith the French or Eomance rather (some- 
times called Lingua Romana rustica) as they were in the 
ninth century after Jesus Christ in the forms of the oaths of 
the sons of the Emperor Louis le Debonnaire, which Xithard, 
their kinsman, has preserved for us.- We find little elsewhere 
of so old French, Italian, or Spanish. But for the Theotisque, 
or ancient German, there is the gospel of Otfried/ a monk of 

1 Cf. Grimm, Deutsrhes Worterbiich, sub " Deutsch." — Tr. 

2 For the text of these famous oaths, taken at Strasburg, Feb. 14, 842, cf. 
Nitbard, c. 790-c. 8.58, Hist., written, at the command of Charles the Bald, 
between 841 and 843, Bk. III., chap. 5, pp. .38, 39, ed. Pertz, and Pertz, Momi- 
mi'nta Germanias Historica, Vol. 2, pp. Giio, 666, where they are jjreserved in the 
old Romance — lingua Romana rustica — and old German — liiu/va Teotis^-a 
— languages. Cf. also Duteus, Leibnitii opera omnia, Vol. 6, Pt. 11., pp. 141- 
144, where " utramque formulam (' jurarunt Ludovicus Romane, Carolus 
Teutonice ') eodem significatu, conceptis verbis ex Nithardo exliibebimus 
interlineariter coUigatam, quia sibi verljotenus respondent, et ipso parallelismo 
illustrantur." The best edition for the study of the old German part of the 
oaths is in Karl Miillenhoif vi. Wilhelm Scherer, Denkmuler deutscher Poesie 
u. Prosa aus VIII-XII Jahrh., Denkm. No. 67, 2 Ausg. Berlin, 1873; 3 Aufl. 
bearbeitet v. E. Steinmeyer. Vol. 2 contains notes summing up the best results 
of critical study. Explanations of the old German text have also been made 
by J. Grimm, 1785-1863, in his Kleinere Schriften, Vol. 6, pp. 403 sq., see 
also Monumenta Germanise Historica, Vol. 2, pp. 465 sq. ; and by H. F. 
Massmann, 1797-1874, in his Die kleinen Sprachdenkhiale des VIII bis XII 
Jahrh. Quedlinburg u. Leipzig, 1839. Fr. Ch. Diez, 1794-1876, "the real 
founder of Scientific Romance philology and linguistics," in his Altromanische 
Sprachdenkmliler, Bonn, 1846, has explained the Romance portion of the text, 
and gives, op. cit. pp. 3-5, a good portion of the literature on this interesting 
linguistic monument. The best textual notes on the Romance or old French 
part of the oaths are in W. Foerster u. E. Koschwitz, Altfranzosisches Uebunys- 
biirh, Heilbronn, 1884; while the best facsimile of the whole fragment, both 
French and German, is the Album of the Societe des anciens textes francais 
{Les plus anciens monuments dc la langue fran<;aise), Paris, 1875. The old 
Romance text, the earliest sjiecimen of French in existence, with a modern 
French translation, is found in Brachet, A Historical Grammar of the French 
Toncjae, 6th English, fi-om 20th French ed., pp. 17, 18, Oxford: Clarendon 
Press, 1884; while to these a Latin version is added for comparison in the 
article on the "Latin Language" prope Jin., in the Encyclop. Brit., 9th ed.. 
Vol. 14, pp. 340, 341 (American Reprint). — Tk. 

3 The gospel of Otfrid, usually called the Life of CJirist, was written in the 
South-Frankish dialect of the Old High German in 867 or 868, and dedicated 
to King Louis the German. Editions of it were published by Matthias Flacius 
Illyricus, 1520-1.575, at Basle in 1571, 8vo, "a book as curious as rare," and 
by Schilter-Scberz in the Thesaurus antiquitatum teutonicum. Vol. 1. Ulrase, 
1727-1728, 3 vols., fol. These have now no critical worth, but merely an historical 



cii. II] ON HUMAN UNDERSTANDING 295 

Weissenburg of this same time, which. Hacius has published 
and which Schilter^ wished to edit anew. The Saxons who 
passed into Great Britain have left us books still more ancient. 
They have a version or paraphrase of the beginning of Genesis 
and of some other parts of the Sacred History, made by a 
Caedmon whom Bede already mentions.^ But the most ancient 
book, not only of the Germanic languages, but of all the lan- 
guages of Europe, except Greek and Latin, is that of the 
gospel of the Goths of the Pontus Euxinus, known by the 
name of Codex Argenteus,^ written in characters entirely pecu- 

interest and value. Cf. H. Paul, Grunclriss d. r/ertn. Philolocjie, II, 214, Stras- 
burg, 1889 — . It has also been edited by E. Tli. Graff, Konigsberg, 1831, 4to, an 
edition good iu its day, but now antiquated ; and more recently by J. Kelle, 
with grammar and glossai'y in 3 vols., Regeiisburg, 185()-1881 ; by P. Piper, 
Paderborn, 1878, containing the fullest critical ajiparatus; and by Erdmann, 
Halle, 1882, the most convenient. Piper has also published a student's edition, 
Freiburg, 1884; and Kelle a ti'anslation, Christi Lebeii vnd Lehre besungen 
von Otfrid, Prag. 1870. Cf. also W. Sclierer, Gesrh. d. dcnischen Lit. (Jth ed., 
pp. 48-51. Berlin, 1801; Eng. trans., from 3d Germ, ed.. Vol. 1, pp. 44-46, 
New York, Chas. Scribner's Sons, 188G. To Otfrid is due, for the most part, 
the introduction into German poetry, in place of the earlier alliterative metre, 
of the rhymed stanza imitated from that of the Latin Church hymns. — Tr. 

1 John Schilter, 1G32-1705, a distinguished German jurisconsult and archae- 
ologist, Pni^essor of Law at Strasburg, and anthor of the work referred to in 
note 3, Thcsaunis antiquitatum teutonicum, which was edited, after Schilter's 
death, by Job. Geor. Scherz, and is filled with documents of great value for 
the civil and literary history of Germany at the time of tlie Carlovingians. 
Schilter was led to linguistic studies through Ids legal and antiquarian investi- 
gations. Cf. Dutens, Leibnit. opera omnia, 6, Pt. II., p. 222, where Leibnitz 
remarks: "I am told that Mr. Schilter, of Strasburg, is none too well, and 
as he is an old man, I fear that his edition of Notger and Otfried will not 
appear. . . . Mr. Schilter makes use, moreover, of the Gothic Gospels ot 
Ultilas, of the Anglo-Saxon, and also of the Icelandic, as well as of other old 
books and glossaries; for we must unite the different dialects of all the Teu- 
tonic peoples in order to explain the old books." — Tr. 

2 On Csedmon, died 080, cf. Bede, iiVcfe.s. Hist., Bk. IV., chap. 24, pp. 217- 
220, 5th ed. (Bohu's Lib.), London: Geo. Bell and Sons, 1884; H. Morley, Eng- 
lish Writers, Bk. II., chap. 4, Vol. 2, p. 71 sq., London: Cassell and Co., 1888; 
B. Ten Brink, Earl;/ Eng. Lit., trans, by H. M. Kennedy, pp. 39-48 and 371- 
386, New York : Henry Holt & Co., 1884 ; S. A. Brooke, Hist of EurUj Eng. Lit., 
pp. 275-;>10, New York: Macmillan & Co., 1892. For the text of the poems 
ascribed to him, cf. Benj. Thorpe, Cxdmon's Metrical Paraphrase of Fart of 
the Holy Scriptxire in Anglo-Saxon ; with an Eng. Trans., Notes, and a Verbal 
Index, London: 1832; C. W. M. Grein, Bibliothek der Angel-Sachsischen 
Poesie, 18.57, Vol. 1 ; new ed. by R. Wiilker, Vols. 1-3, 188:3-1889, still in prog- 
ress ; the vol. containing Credmon has not yet (1892) appeared ; T. W. Hunt, 
Csedmon's Exodus and Daniel, Boston: Ginn & Co., 4th (id., 1889. — Tr. 

3 The Coilex Argenteus — Silver Cod(!x — so calhid because written in silver 
and gold letters upon purple-stained vellum and bound iu silver, as was the 



200 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 



liar, whioh was found in tlie ancient monastery of the Benedic- 
tines of Wei-den in Westphalia, and has been carried into 
Sweden, where it is preserved, as with reason it should be, 
with as much care as the original of the Pandects in Florence, 
although this version was made by the Eastern Goths and in a 
dialect far removed from the Scandinavian German ; but it is 
because they believe, with some probability, that the Goths 
of the Pontus Euxinus came originally from Scandinavia, or 
at least from the Baltic Sea. Now the language or the dialect 
of these ancient Goths is very different from the modern 
German, although it has the same linguistic basis. The 
ancient Gallic was still more different, to judge by the lan- 
guage most nearly approaching the true Gallic, wdiich is that 
of the country of Wales, Cornwall, and Basse-Bretagne ; but 
the Irish differs therefrom still more and shows us traces of a 
Britannic, Gallic, and Germanic language, still more ancient. 
But all these languages come from one source, and may be 

case with costly Mss. in those days, originally consisted of 330 leaves con- 
taining the Gospels in the following order: Matt., John, Luke, Mark, trans- 
lated into the Gotliic language, about the middle of the fourth century, by 
Bishop Umias (Vulfila), 311-383. Only 177 leaves now remain. Cf. F. L. 
Stamm, Vlfilas, 1872, new ed. by M. Heyne, Paderborn, 1885, Einleitung, p. ix. 
The Ms., like all existing Gothic Mss., seems to have been written in Italy 
during the rule of the East Goths in the first half of the sixth century, and, 
after many adventures, was at last carried in 16G9 to Upsala, where it now 
is. It is one of the few sources of our knowledge of Gothic, and, as Ulfilas 
was a fine scholar, and made his translation of the New Testament from the 
Greek original, with frequent comparison of the Latin versions, it is of some 
value in New Testament textual criticism. Editions of Ulfilas may be named 
as follows: The two earlier, by H. C. v. d. Gabelentz and J. Loebe, 3 vols., 
Altenburg u. Leipzig, 184;>-1846, and H. F. Massmaun, Stuttgart, 1855-1856, 
2 vols. Svo, rest upon still older single editions with many faults. Cf. 
H. Paul. Grundriss d. f/erm. Philolor/ie, II, 69, Anm. 2. The critical editions 
of A. Uppstrom: Codex Arfjenteus, Upsala, 1854-1855; Decern codicis arg. 
redtviva folia, ih. 1857; Fragmenta gothica selecta, ib. 18G1; Codices gothici 
Ambrosiani, Stockh. u. Leipzig, 18(54-1868, in whose work for the first time 
was laid an entirely secure foundation for Gothic text-criticism, and upon 
whom the later editions rest. Cf. H. Paul, oj). cit.; and Stamm-Heyne, 
Ulfilas, Einl. p. xi. The larger ed. of E. Bernhardt, Vulfila, oder die gotische 
Bibcl, Halle, 1875, is the best for comparison with the Greek ; while his smaller 
ed., Bie gotische Bibel des Vulfila, Halle, 1884, and that of Stamm-Heyne cited 
above are the most convenient. The best introduction to Gothic in English is 
J. Wright, A Primer of Gothic, London and New York, Macmillan & Co., 
1892. Cf. also W. Scherer, Gesch. d. deutschen Lit., 6th ed., pp. 33-36, Eng. 
trans.. Vol. 1, pp. 28-32; Waitz, Bas Leben des Ulflas, 1840: KraiTt. Kirchen- 
geschichte d. Beutschen Volker, Abth. 1, 1854, and article " Ulfilas," in Herzog, 
Sealencyklopiidie, Vol. 16, 1885. — Te. 



CH. II] ON HUMAN UNDERSTANDING 297 

taken as modifications of one and the same language, which 
may be called the Keltic. Thus the ancients called both the 
Germans and the Gauls Kelts ; and in going back farther in 
order to understand the origin both of the Keltic and the 
Latin and the Greek, which have many roots in common with 
the Germanic or Keltic tongues, we may conjecture that this 
fact arises from the common origin of all these peoples de- 
scended from the Scythians, who, having come from the Black 
Sea, passed the Danube and the Vistula, and of whom one part 
may have gone into Greece, the other have filled Germany and 
the Gauls ; a consequence of the hypothesis which makes the 
Europeans come from Asia. The Sarmatian (sixpposing it to 
be the Sclavonic) has at least half its origin either Germanic 
or common with the Germanic. The case appears to be some- 
what similar, indeed, in the Finnish language, which is that of 
the most ancient Scandinavians, before the Germanic peoples, 
i.e. the Danes, Swedes, and Norwegians, had taken possession 
of the land which is the best and nearest the sea; and the 
language of the Finns or of the northeast of our continent, 
which is also that of the Lapps, extends from the German or 
jSTorwegian Ocean even to the Caspian Sea (although inter- 
rupted by the Sclavic peoples which have been thrust in 
between the two) and has some relation to the Hungarian, 
having come from the countries which are now in part under 
the Muscovites. But the Tartar language, which has filled the 
northeast of Asia, with its variations, appears to have been that 
of the Huns and Cumans as it is of the Uzbeks or Turkomans, 
of the Kalmuks and of the Mongols. Now all these languages of 
Scythia have many roots common among themselves and with 
ours, and it is found that even the Arabic (under which the 
Hebrew, the ancient Punic, the Chaldee, the Syriac, the Etlii- 
opic of the Abyssinians are to be comprised) has so great a 
number of them and an agreement so manifest with ours that 
it cannot be attributed to chance alone, nor even to commerce 
alone, but rather to the migrations of the peoples. So that 
there is nothing in tliis to combat and not rather to favor the 
view of the common origin of all nations, and of a primitive 
root language.^ If the Hebrew or the Arabic approaches the 

1 Leibnitz was the first wlio, from the point of view of a presentiment of the 
kindred connection, first of the European, and then of tho remaining Ian- 



298 LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 

nearest to it, it must be at least much changed, and the 
Gorman seems to have preserved more completely the natural 
and (to use the language of Jacob Boehme) the Adamic;^ for 
if we had the primitive language in its purity, or sufficiently 
preserved to be recognizable, the reasons of the connections 
whether natural or of an arbitrary institution would necessa- 
rily appear wise and worthy of the primitive author. But 
supposing that our languages are derivative as regards their 
foundation, they nevertheless have something primitive in 
themselves which has arisen from them in relation to new 
root Avords^ since formed among them by chance but upon 
natural grounds. Those which signify the sounds of animals 
or have come from them furnish examples. Such, for exam- 
ple, is the Latin coaxare attributed to the frogs, which has 
some relation to couaquen or quaken in German. Now it 

guages, demanded and hinaself urged on the comparative study of languages, 
and in this, as in so many other things, was far in advance of his time. For 
his linguistic work, cf. Dutens, Leibnit. opera omnia, Vols. 5 and 6. — Tr. 

1 Jacob Boehme, 1575-1()24, a celebrated theosophist, in whom Protestant 
mysticism reached its highest point. He is called philosophus teutonicus, and 
" in reality through him, for the first time in Germany, did jahilosophy come 
forward with a characteristic stamp " ; Hegel, Vorlesung. ti.d. Gesch. d. Philos., 
Vol. 3, p. 270, 2d ed., Berlin, 1833. O. Pfleiderer, Religionsphilosophie, Vol. 
1, p. 20, 2d ed., Berlin, 1883, says, "The theosophy of Boehme shows itself as 
the direct forerunner of tlie metaphysic of Leibnitz, 1646-171(5, Schelling, 1775- 
1854, Baader, 1765-1841, Schopenhauer, 1788-1860, etc." For his philosophy, 
etc., cf. his Sdmmtliche Werke, hrsg. v. K. W. Schiebler, Leipzig, 1831-47, 2d 
ed., 1861 sq.; also Hegel, op. cit., Vol. 3, pp. 270-297: Stockl, Gesch. d. Philos. 
d. Mittelalters, Vol. 5, pp. 569-608, §§ 122-128; O. Pfleiderer, op. cit., Vol. 1, 
pp. 15-23, Eng. trans.. Vol. 1, pp. 13-23; B. Piinjer, Gesch. d. Christ. Beligions- 
philos., 1880-83, Vol. 1, pp. 180-194; Eng. trans.. Vol. 1, pp. 243-265, f. and 
T. Clark, Edinburgh, 1887. Vaughan, Houis ivith the Mystics, Vol. 2, pp. 79-125, 
3<1 ed., London : 1879. According to Boehme, cf. Das dreyfache Leben, chap. 8, 
2-4; Princ, 10, 8-12; Myst. May., cliap. 15, 1-9, etc.; also Stockl, op. cit., §§ 
125, 126, A''ol. 3, pp. 586 sg. ; Adam, who stands here in Leibnitz's text " as the 
symbol and representative of the original unity of the race," and of its lan- 
guage, " was destiired to propagate his race in angel-like jnirity without 
endangering its integrity." Leibnitz, while acquainted with Boehme's writ- 
ings, made little use of them in his own thinking, and speaks thus of them in 
a letter to Fr. S. Loeflfler, Jan. 13, 1693, cf. Dutens, op. cit.. Vol. 5, p. 409 : " The 
controversies over the opinions of Boehme I consider idle, and think that he 
neither understood himself nor have others understood him." — Tr. 

2 Gerhardt's text reads: "Qui leur e.st survenu par rapport a des mots 
radicaux nouveaux, formes depuis chez elles." etc. Erdmann and Jacques 
read: "qui leur est survenu par i-apport a des mots I'adicaux et nouveaux 
radicaux forme's depuis chez elles," etc.; i.e. new root words and new roots 
since formed among them, etc. — Tr. 



J 



CH. II] ON HUMAN UNDERSTANDING 299 

seems that the noise of these animals is the primordial root of 
other words of the German language. For as these animals 
make much noise, the term is attributed to-day to idle talk and 
to babblers, who are called quakeler in the diminutive form ; 
but apparently this same word quaken was formerly under- 
stood in a good sense and signified all sorts of sounds made 
with the mouth not even excepting speech. And as these 
sounds or noises of animals are an evidence of life, and as we 
know thereby before we see it that there is life there, quek in 
old German has come to signify life or living, as may be 
observed in the most ancient books, and there are also traces 
of the same in the modern language, for Quecksilber is quick- 
silver (vif-argent) , and erquicken is to strengthen, and, as it 
were, to vivify or recreate after exhaustion or some great 
labor. Certain weeds are called also in Low German Quaken, 
alive so to speak and running, as they say in German, which 
spread and propagate themselves easily in the fields to the 
detriment of the grain ; and in English quickly means promptly 
and in a wide-awake manner. Thus we may consider that as 
regards these words the German language may pass as the 
primitive, the ancients having no need to borrow elsewhere a 
sound which is the imitation of that of the frogs. And there 
are many others in which the same thing appears. For it 
seems that the ancient Germans, Kelts, and other peoples 
allied to them have employed by a natural instinct the letter R 
to signify a violent movement and a noise like that of this 
letter.^ It appears in pew, fluo, rinnen, riiren (Jluere), rutir 
(flKxirm), the Rhine. Rhone, Roer (Rhenus, Rhoclanus, Erida- 
Mis, Rura), ratiben (rapere, ravir), Radt {rota), radere (raser), 
rauschen, a word difficult to translate into French; it signifies 
a noise like that which the wind or a passing animal stirs up 
in the leaves or the trees, or is made by a trailing dress ; 
reckken (to stretch with violence), whence it comes that reichen 
is to reach ; that der Rick signifies a long stick or perch useful 
for suspending anything, in this kind of Plat-tiitscli or Low 
Buxon which is (spoken) near Brunswick; that Rige, Reihe, 

1 Cf. Plato, Cratylus, 434 sq.; English Translation by B. Jowett; 2d ed., 
1875, Vol. 2, p. 259 sq.; 3d od., 1892, Vol. 1, p. .381 sq., wliere the author has 
already made an attempt, similar to that ninde here and many times Ix-lore 
hy Leihiiitz, to fix the original sijj;nificauce oi single letters in the formation 
of words. — Tr. 



800 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

retjula, rerjere, refer to length or a straight course ; and that 
lieck lias signified a thing or person very extended and long, 
and in particular a giant, and then a powerful and rich man, 
as it appears in the reich of the Germans and in the riche or 
rkco of the Semi-Latins. In Spanish ricos hombres means the 
nobles or chief men ; and this makes it plain at the same time 
how metaphor, synecdoche, and metonymy have caused words 
to pass from one signification to another without our being 
able always to trace them. This noise and violent movement 
is noticed also in Hiss (rupture) Avith which the Latin rximpo, 
the Greek prjyvvfjn, the French arracher, the Italian straccio are 
connected. Xow as the letter R signifies naturall}^ a violent 
movement, the letter L designates a gentler one. Thus we see 
that children and others who find the R too harsh or too difii- 
cult to pronounce substitute for it the letter L, saying, for 
example, moii levelend pUe} This gentle movement appears in 
lehen (yivre — live), lahen {confoHer — comfort, faire vivre — 
make live). Unci, lenis, lentus {lent — slow), lieben (aimer — 
love), lauffen {glisser promptement comme Veau qui coule — to 
glide quickly like flowing water), labi (glisser — to touch 
lightly, labitur uncta vadis abies^), legen (mettre doncement — to 
place gently), whence comes liegen (coucher — to lie down), 
lage or laye (un lit, comme un lit de pjierres — a bed, as a bed of 
rocks), Lay-stein (pierre iX couches, ardoise — slate), lego, icJi lese 
(Je remasse ce qu'on a mis — I collect what has been invested, 
it is the opposite of mettre — to place, and then je lis — I read, 
and finally among the Greeks je parle — I speak ^), Laub 
(feuille — leaf), a thing easy to stir, to which are related also 
laj), lid,* lenken, luo, \vw (solco), leien^ (in Low-Saxon) to dis- 
solve, to melt like the snow, whence the Leine has its name, 
a river of Hanover, which, rising in the mountainous coun- 
tries, is greatly enlarged by the melted snows ; not to speak 
of an infinite number of other similar appellations, which prove 
that there is something natural in the origin of words which 
indicates a relation between things and the sounds and move- 

1 I.e. " Reverend pere." — Tr. 2 Qf^ Vergil, ^n. 8, 91. — Tr. 

3 Erdmann and Jacques omit: " Et puis je lis et enfin chez les Grecs je 
parle," the reading of Gerhardt. — Tr. 

* Gerhardfs reading ; Erdmann and .Jacques have " liel." — Tr. 
3 Gerhardfs reading; Erdmann and Jacques have "lien." — Tr. 



CH. II] ON HUMAN UNDERSTANDING 301 

inents of the vocal organs ; and it is furthermore for that 
reason that the letter L joined to other nouns makes their 
diminutives with the Latins, the Semi-Latins, and the High 
Germans. But it must not be pretended that this reason can 
be noticed everywhere, for the lion, the lynx, the wolf, are 
anything but gentle. But it may be attached to another acci- 
dent, the speed (/a«/), which makes them feared or compels 
flight ; as if the one who sees such an animal coming should 
cry to the others : lauf {fuyez ! — fly !) ; besides by many acci- 
dents and changes the majority of words are very much 
altered and diverted from their pronunciation and original 
signification. 

Ph. Yet an example would make it better understood. 

Th. Here is one plain enough and which comprehends many 
others. The word oe.il (eye) and its parentage may serve us. 
To show it I will begin a little further back. A (the first 
letter) followed by a little aspiration makes Ah, and as this 
is an emission of the air which produces a sound clear enough 
at its beginning and then vanishing, this sound naturally sig- 
nifies a light breath {spiritus lenis) when A and H are not 
very strong. Thence it is that aw, aer, aura, haugh, halare, 
haleine, ar/xos, Athem, Oclem (in German) have had their origin. 
But as water is also a fluid and makes a noise, it has come 
(it seems) that ah made rougher by doubling, i.e. aha or ahha, 
has been taken as water. The Teutons and other Kelts, the 
better to indicate the motion, have placed their W before 
both. Thence wehen, Wind, vent, indicate the motion of the 
air, and loaten, vadum, water, motion of or in the water. But 
to return to aha, it appears to be (as I have said) a kind of 
root which means water. The Icelanders, who preserve some- 
what of the Scandinavian Teutonic, have lessened the aspira- 
tion of some by saying aa; others, who say Aken (meaning 
Aix, Aqnae grani^), have increased it, as do also the Latins in 
their aqua, and the Germans in certain places, who say ach 
in compositions to indicate water, as when Schivarzach^ means 
black water, Biberach water of the beavers. And instead of 
Wiser or Weser they said Wiseraha in the old titles, and 
WisKvarh- among the ancient inhalntants, of which the Latins 

1 I.e. A(|iiis Graiuim, Aix-l;i-Cbai)elle. — Tr. 

'■2 (icilianlt's reading; Enlmanu ami .Jacqnos road: " Rolnvartzacli," 
" Wiscracli." — Tr. 



;;()- LEIBNITZ'S CRITIQUE OF LOCKE [bk. jii 

have made Visurgis, as from Her, llerach, tliey have made 
Jlargus. From aqua, aiyues, auue the French have finally 
made eau, which they pronounce oo, in which there no longer 
remains anything of its origin, Auive, Auge with the Ger- 
mans is to-day a place Avhich water often overflows, suitable 
for pasturage, locus irrignus, jMsmius; but more particularly 
it signifies an island, as in the name of the monastery of 
Bi'ichenaii {Augia dives), and many others. And this (process) 
must have gone on among many of the Teutonic and Keltic 
peoples, for thence it has come that everything which is, as 
it were, isolated in a kind of plain has been called Aiige or 
Ouge, oculus. Thus it is they name spots of oil upon water 
among the Germans ; and among the Spaniards ojo is a hole. 
But Auge, Ooge, oculus, occliio, etc., have been applied more 
particularly to the oe,il, as it were, pre-eminently, which makes 
this isolated brilliant foramen in the countenance ; and doubt- 
less the French ceil comes from it also, bu.t its origin is not 
at all recognizable, unless by the concatenation I have just 
given ; and the o/x/xa and oi/'ts of the Greeks appear to come 
from the same source. Oe or Oeland is an island among the 
inhabitants of the North, and there is some trace of it in the 
Hebrew, where *i^, Ai, is an island. Bochart ^ believed that 
the Phoenicians derived the name which he thinks they gave 
to the ^gean Sea, full of islands, from the same source. 
Augere, augmentation, comes also from Auue or Auge, i.e. from 
the effusion of waters, as ooJcen, auken in old Saxon was to 
augment ; and Augustus, when speaking as Emperor, was trans- 
lated by OoJcer. The river of Brunswick, which comes from 
the Hartz Mountains, and consequently is much subject to 
sudden accretions, is called Ocker, formerly Ouacra. And I 
mention in passing that the names of rivers, having ordinarily 

1 Samuel Bochart, 1599-1667, an eminent French scholar and Protestant 
theologian, a distinguished orientalist, and a man of profound erudition, 
thoroughly familiar with all the principal oriental languages, including 
Hebrew, Chaldaic, Syriac, and Arabic, and so enthusiastic in linguistic studies 
that even when far advanced in years he desired to learn Ethiopic. His 
favorite study was Phoenician, and though modest and candid he seeks to 
derive all languages etymologically " from the Hebrew or Phoenician," a pro- 
cedure which led him into many fanciful etymologies. Cf. Dutens, Leibnit. 
opera omnia, Vol. 6, Pt. H., pp. 223, 226. His complete works were published 
under the title, Sam. Bochart, opera omnia. Leyden, 1675, 2 vols, fol., 1692, 
1712, 3 vols. fol. Leibnitz jirized and often cited them. — Tk. 



I 



CH. II] ON HUMAN UNDERSTANDING 303 

come from the farthest known antiquity, show best the old 
hmguage and the ancient inhabitants ; hence they deserve 
particular investigation. And languages in general being the 
most ancient monuments of peoples, before writing and the 
arts, show best the origin of cognations and migrations. 
Hence etymologies much extended would be curious and sig- 
nificant; but it is necessary to unite the languages of many 
peoples, and not to make too many leaps from one nation to 
another far distant without having good verifications, in which 
process it is especially useful to have intervening peoples as 
guarantees. And in general credence must be given to ety- 
mologies only when there is a quantity of concurrent evidence ; 
to do differently is to goropise. 

Ph. To gorojnse? What does that mean? 

Th. It means that the strange and often ridiculous etymol- 
ogies of Goropius Becanus,^ a learned physician of the sixteenth 
century, have passed into a proverb, although otherwise he 
may not have been excessively wrong in claiming that the 
German language, which he calls Cimbric, has as many, yes, 
more, marks of a primitive character than the Hebrew itself. 
I remember that the late Mr. Clanberg,- an excellent philoso- 

1 John Becan, 1518-1572, a Belgian physician and scholar, wliose real name 
was Van Gorp — Latinized as Goropius Becanus. He practised medicine for 
some years at Antwerp, but finally gave himself wholly to the study of 
antiquity, belles-lettres, and ancient languages. In a public lecture at Liege, 
he attempted to demonstrate that the language of Adam was the Flemish or 
Teutonic, a \iew which he set forth at length in his Orirjines Antwerpianm sive 
Cimmeriorum Becceselana, etc., Antwerp, 1569, fol. ; and, as at that time he 
considered the Netherlands to be the site of Paradise, to derive language in 
general from the Low-German, which he calls the Cimbric, in his paper 
Hermathena, Bk. II., p. 26 sq. Cf. Joannis Goropii Becani opera hactenus in 
lucem non eclita; nempe, Hermathena, etc., Antwerp, 1580, fol. — Tr. 

2 John Clauberg, 1622-16(55, a German philosopher of the Cartesian school, 
who, first as a comifeentator merely and afterwards more independently, 
introduced and expounded the philosophy of Descartes in the universities at 
Herhorn and Duisburg, where he was professor successively of theology and 
philosophy. He wrote a commentary on the Meditations of Descartes, and in 
his own speculations anticipated much of the snl)sequeTit develojiment of Car- 
tesianism. In his Be conjunctione animx et corporis human i sfriptnm., he 
maintained that bodily movements are antecedents only and not strictly causes 
of mental action, a view similar to that of Malebranche. He pro])osed for 
metaphysics the name Ontosophy or Ontology, a hint which Christian Wolf, 
1679-1754, afterwards followed. Of. Erdmann, Gnind. d. Gesrh. d. Philns., 
§§ 268, 4, 290, 4, Vol. 2, pp. 33, 187, "3d ed., Berlin, 1878, and English trans, ad 
lor. His Ontosophia, de corjnitione Dei et nostri appeared at Muhlberg, 1087, 



:\i)l LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

plior, has jmblislied a brief essay upon the sources of the 
Gennan hiiiguage which makes one regret the loss of that 
which he had promised upon this subject. I have myself 
published some thoughts upon the subject, besides inducing 
the late Gerard Meier,^ a theologian of Bremen, to work upon 
it, which he did till death interrupted him. I hope, however, 
that the public will yet one day profit from his labors as well 
as from the similar labors of Mr. Schilter,- a celebrated juris- 
consult at Strasburg, but who also has just died. It is certain 
at least that the Teutonic language and antiquities enter into 
the majority of the researches into European origins, customs, 
and antiquities. And I wish that learned men w^ould make 
as much of them in the languages of the Wallachians, Bis- 
cayans, Slavonians, Finns, Turks, Persians, Armenians, Geor- 
gians, and others, the better to discover the harmony which 
would particularly be of service, as I have just said, in clearing 
up the origin of nations.] 

§ 2. Ph. [This design is important, but at present it is time 
to leave the matter of ivorcls, and to return to their form, i.e. to 

1 vol., r2mo; and his Opera 2^hilosop7iica at Amsterdam, 1691, 2 vols., 4to. 
Leibnitz liad a Ligli regard for him, both as a philologist and philosopher, 
and in one expression apparently places him even above Descartes; " Carte- 
sius voliiit quaedam emendare in physicis, disjilicet tamen audacia et fastiis 
nimius conjunctus cum stili obscuritate, conf usione, maledicentia. Longe magis 
mihi probatus Claubergius, discipuliis ejus, pleuus, perspicuus, brevis, method- 
icus." Cf. Otium Hanoveranum, ed.-J. F. Feller, p. 181, Lipsire, 1718; Dutens, 
Leihnit. opera omnia, Vol. 6, Pt. I., p. 311. Leibnitz frequently mentions him 
and his works, particularly the Meditationes et collectanea linguss Teutonicse, 
Duisburgi, IGBS, and the booklet Ars etynioloriica Teutonvm; cf. Dutens, 
op. cit., Vols. 5, p. 334; 6, Pt. II., pp. 28, 179, 22o! In the Ar.? etymol. Teuton. 
Clauberg puts it forth as a fundamental proposition that the German must be 
explained as an original language. Cf. L. Neff.. G. W. Leibniz als Sprach- 
forscher rind Etifmologe, Pt. I., p. 16 sq., Heidelberg, 1870. — Tr. 

1 Gerard or Gerhard Meier or Sleyer, who was incited by Leibnitz to the 
study of German philology, and collected an abundance of select materials for 
a Grammatica Germanica and Glo.tsarium Sayonicum, but was prevented 
from completing the work be.gvin by his early and sudden death; cf. Eccard, 
Collectanea etymologica, 2 vols., 8vo, Hannoverse, 1717, Eiuleitung, p. 52, and 
Dutens, Leihnit. opera omnia, Vol. 6, Pt II., p. 145, note. Leibnitz states that 
the Glo.ssar. Saxon, was planned and undertaken with his encouragement, and 
that it will contain much erudition; cf. Dutens, op. r;7.. Vols. 5, p. 115; C, 114, 
and note. For the correspondence between Mej'er and Leibnitz, which exhib- 
its Meyer's method in his etymological work, cf. Dutens, op. cit.. Vol. 6, Pt. 
II., pp. 14.5-176. Leibnitz says : " His learning and character are esteemed by 
all " — " Doctrina ejus, et virtus apud omnes in pretio habentur," Dutens, op. 
cit.. Vol. 5, p. 105. — Tk. 2 Cf. ante, p. 295, note 1. — Tr. 



CH. II] ON HUMAN UNDERSTANDING 305 

the meaning wliicli is common to the different languages.] 
Now you will agree with me in the first place, sir, that when 
one man speaks to another it is of his own ideas that he wishes 
to give signs ; the words cannot be applied by him to things 
which he does not know. And until a man has ideas of his 
own he cannot suppose them to correspond to the qualities of 
things or to the conceptions of another. 

Th. [It is true, however, that he intends very often to 
indicate what others think rather than what he himself 
thinks, as happens only too much in the case of the laity, 
whose faith is implicit. But I admit that he always means 
something general, however hollow and destitute of intelli- 
gence the thought may be; and he takes pains at least to 
arrange his words .according to the custom of others, content- 
ing himself with the belief that their sense can be apprehended 
at need. Thus he is sometimes only the interpreter (truche- 
man) of thoughts, or the bearer of the word of another, just as 
a letter would be ; and indeed this is the case oftener than you 
think.] 

§ 3. Ph. [You are right in adding that he always means 
something general, however idiotic it may be.] A child hav- 
ing noticed in what he hears called gold only a brilliant yellow 
color, gives the name of gold to this same color which he sees 
in a peacock's tail; others will add great weight, fusibility, 
malleability. 

Th. [I admit it ; but often the idea you have of the object 
of which you speak, is still more general than that of this 
child, and I doubt not that a blind person can speak pertinently 
of colors and make a speech in praise of the light which he 
does not know, because he has learned its effects and circum- 
stances.] 

§ 4. Ph. Your remark is quite true. Men often apply their 
thoughts more to words than to things, and because they have 
learned most of these words before becoming acquainted with 
the ideas which they signify, not only children, but also grown- 
up men often speak like parrots. § 5. But men ordinarily mean 
to indicate their own thoughts, and further they attribute to 
words a secret relation to the ideas of another and to things 
themselves. For if the sounds were attached to another idea 
by the one with whom we are conversing, it would be necessary 

X 



306 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

to speak twi) languages. It is true that one does not stop too 
much to examine what the ideas of others are, and our idea is 
supposed to be that which the common people and the scholars 
of the country attach to the same word. § G. This is particu- 
larly the case as regards simple ideas and modes ; but as 
regards substances the belief is more particularly that the 
words signify also the reality of things. 

Th. [Substances and modes are equally represented by 
ideas; and things, as well as ideas, in both cases are indi- 
cated by words ; thus I see but little difference, save that 
ideas of substances and of sensible qualities are more fixed. 
For the rest, it sometimes happens that our ideas and thoughts 
are the matter of our discourse and constitute the thing itself 
which we desire to signify, and that reflective notions enter 
more than we think into those of things. We speak, indeed, 
sometimes of words in a material way, without in this case 
being able to substitute with precision in the place of the 
word its signification or its relation to the ideas or things.^ 

1 Leibnitz here points out a source of manifold, far-reaching and influential 
errors, especially fatal in philosophy, viz. the hypostasizing of concepts, i.e. 
regarding and using universal thouglit-symbols as substances, a consequence 
of the excessive use of abstract terms. To these errors thus arising from the 
imperfection and abuse of words and their influence on the mind, Francis 
Bacon, 15()l-lti2tj, in his Nov. Org. Bk. I., Aphor. 43, 59, 60, gives the name 
of idolafori, idols of the market-place, and says they are "omnium molestis- 
sima " — " the most troublesome of all." These words are either names merely 
of non-existent things or of things sujiposed to exist because of these names, 
or are names obtained by " vicious and unskilful abstraction" — "mala et 
imperita abstractione " — from a few objects and indiscriminately applied to 
all other things having tlie faintest analogy thereto. The best ed. of Bacon's 
Works is that of Ellis, Spedding, and Heath, 2d ed., 7 vols., London: Long- 
mans, 1870-72. The Nov. Org., in Latin, is in Vol. 1, the Eng. trans, in Vol. 4 
of this ed. Editions of the Nov. Org. (Latin) have been published with Eng. 
notes, and an Eng. trans, in a separate vol., by G. W. Kitchin, Oxford: Clar- 
endon Press, 1855; and with Introd., Notes, etc., by Thos. Fowler, Oxford: 
Clarendon Press, 1878. 

For Leibnitz's estimate of Bacon, whose Be Aug. Scient. he mentions 
among the writings which happily chanced to come into his hands when a 
youth, and with others helped to direct his studies in the right path, whom he 
enumerates among " the founders of modern philosophy," and whose method 
he applied in his reform of the science of language, cf. Gerhardt, Die philos. 
Schrift. ". G. W. Leibniz, Vols. 1 : 196; .3 : 7, 16; 4 :'l4.3, Erdmann, Leibnit. 
' opera philos., p. 61, b; G. 4 : 64, E. 23, a; G. 4 : 105, E. 45, a, also G. 7 : 325, 
E. 110, b; G. 4 : 3.37, 343; 7 : 52, 53, E. 91, b, 92; G. 7 : 67; 7 : 495, Dutens. 
Lpibnit. opera omnia, 5 : 368; 6 : 303; G. 7 : 51S, E. 421, a. Cf. also John 
Nichol, Bacon, Vol. 2, pp. 238-239 (Philos. Classics), Edinburgh: Wm. Black- 



cH. in] ON HUMAN UNDERSTANDING 307 

This occurs not only in speaking as a grammarian, but also in 
speaking as a lexicographer, in giving the explication of the 
term.] 



CHAPTER III 

OF GENERAL TERMS 

§ 1. Ph. Although particular things alone exist, the larg- 
est number of words are general terms, because it is impossible, 
§ 2, for each particular thing to have a particular and distinct 
name; besides the fact that in such case a prodigious memory- 
would be necessary, in comparison with which that of certain 
generals who could call by name all their soldiers would be 
nothing. The matter indeed becomes infinite, if every animal, 
every plant, and even every leaf of a plant, every grain, in 
short every grain of sand, which might need a name must 
have its name. [And how name the parts of things sensibly 
uniform, as water, fire ?] § 3. Besides, these particular names 
would be useless, the principal end of language being to 
excite in the mind of him who listens to me an idea similar to 
mine. [Thus the similitude suffices, which is indicated by 
general terms.] § 4. And particular words alone Avould not 
serve to extend our knowledge, [nor to make us judge of 
the future by the past, or of one individual by another.] 
§ 5. But as it is often necessary to mention certain individuals, 
particularly of our species, use is made oi propernames ; which 
are given also to countries, towns, mountains and other dis- 
tinctions of place. And horse-jockeys give proper names 
even to their horses, as well as Alexander to his Bucephalus, 
in order to be able to distinguish this or that particular horse 
when he is out of their sight. 

Th. [These remarks are good, and some of them agree 
with those I was about to make. But I would add, in accord- 
ance Avith the observation I have already made, that proper 
names have been ordinarily appellatives, that is to say, general 

wood & Sf)iis, 18S0. For a brief comparison of lAMbnitz and Bacon and of 
tlii'ir i)liilos()|iiii(',s, cf. J. T. iMcrz, Leibniz, pp. 21, 71 (Blackwood's Philos. 
Clas.sics), Edinburjjli: 1884. — Tk. 



308 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 



in their origin, as Brutus, Ca3sar, Augustus, Capito, Lentulus, 
l*iso, Cicoro, Elbe, Rhiue, Kulir, Leine, Ocker, Bucephalus, 
Alps, Brenner or Pyrenees ; for you know that the first 
Brutus had this name from his apparent stupidity, that 
Ciesar was the name of a child drawn by incision from the 
womb of his mother, that Augustus was a name of veneration, 
that Capito is a large head as also Bucephalus, that Lentulus, 
Piso, and Cicero were names given in the beginning to those 
who cultivated in particular certain kinds of vegetables. I 
have already said what the names of these rivers signify, 
Rhine, Ruhr, Leine, Ocker. And you know that all rivers are 
still called Elbe in Scandinavia. Einally Alps are mountains, 
covered with snow (with which agrees album, white) and 
Brenner or Pyrenees signifies a lofty pride, for &ren was high 
or chief (as Brennus) in Keltic, as also hrinck with Low- 
Saxons is pride, and there is a Brenner between Germany and 
Italy as the Pyrenees are between Gaul and Spain. Thus I 
would venture to say that nearly all words are originally gen- 
eral terms, because it will only rarely happen that an express 
name will be invented without reason to indicate one such 
individual. We can say then that the names of individuals 
were names of a species which was given par excellence or 
otherwise to some individual, as the name large head to that 
one of the whole city who had the largest or who was the 
most important of the large heads which were known. Thus 
it is indeed that we give names of genera to the species, i.e. 
that we shall content ourselves with a term more general or 
more vague to designate more particular species, when we 
have no concern for their differences. Por example, we are 
contented with the general name, wormwood, although there 
are so many species of it that one of the Bauhins ^ has filled a 
book expressly with them.] 

1 Jean Bauhin, 1541-1613, a Swiss physician and naturalist, who devoted 
himself chietly to hotany, and with his brother Gaspard, 15(30-1()24, also a 
physician and botanist, was horn at Basel, whither his father, an eminent 
French physician, had tied in exile because of his conversion to Protestant- 
ism. He studied with the celebrated botanist Fuchs at Tubingen, and after 
travelliuff and collecting plants in the Alps, in France, and in Italy, became, 
in 1570, physician to Duke Ulrich of Wiirtemberg at Montbeliard, where he 
reniained till his death. The work of his to which Leibnitz here alludes is 
entitled De plantis ahsinthii nomen hubcntibus. It appeared at Montbeliard 



CH. Ill] ON HUMAN UNDERSTANDING 309 

§ G. Ph. Your reflections upon the origin of 2jroj)er names 
are very just ; but to come to that of appellative names or 
general terms, you will doubtless agree, sir, that words 
become general when they are signs of general ideas, and 
ideas become general when sej^arated by abstraction from 
time, place, or such other circumstances as may determine them 
to this or that particular existence. 

Th. [I do not deny this use of abstraction, but it is rather 
in ascending from species to genera than from individuals 
to species. For (paradoxical as it may appear) it is impos- 
sible for us to have the knowledge of individuals, and to 
obtain the means of detennining exactly the individuality of 
anything, at least of keeping it by itself ; for all the circum- 
stances may reappear ; the smallest differences are to us insen- 
sible ; place or time, far from determining themselves, need 
themselves to be determined by the things they contain. The^ 
most important factor in the problem is the fact that individu- /\ 
ality includes infinity, and only he who is capable of com- ^^ 
prehending it can have the knowledge of the principle of 
individuation of this or that thing. This arises from th^ 
influence (understanding it healthfully) of all things in the 
universe upon each other. It is true that this would be 
the case, if the atoms of Democritus existed, but in tliat case 
also there would be no difference between two different individ- 
uals of the same form and size.] • 

§ 7. Ph. It is, however, wholly evident that the ideas which 
children frame of persons with whom they converse (to con- 
fine ourselves to this example) are similar to the persons 
themselves, and particular only. The ideas they have of 
tlieir nurse aiid their mother are very well traced in their 
minds, and the names nurse and mamma, which children use, 
relate only to these persons. Afterwards when time has 
shown them that there are many other beings resembling 

in 1593. His most important work, composed with the assistance of Iiis fellow- 
countryman and son-in-law Cherler, and containing descriptions of about 5000 
plants with 3577 figures, is the Ilistorin vniversalis plantarum nova et absolu- 
tismna, Yverdun, 1(;50-1(!51, 3 vols., fol. An abridgment of this great work 
was published by Clial)ree, of Geneva, with the title SdafiruphiK, l(i()(i, con- 
taining in one volume all the figures, together witli all of importance on the 
nomenclature and number of sjjccies in the great work. Ho was one of the 
founders of modern Itotany. — Tu. 



310 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

their father or mother, they form an idea in which they find 
tluit all these particular beings equally share, and they, as 
others, give it the name of man. § 8. They acquire in the 
same way names and notions more general ; for example, the 
new idea of animal is not produced by any addition, but only 
by removing the figure or the particular properties of man, 
and retaining a body accompanied by life, feeling, and spon- 
taneous movement. 

Th. [Very well ; but that shows only what I just said ; for 
as the child advances by abstraction from the observation of 
the idea of man to that of the idea of animal, he has come 
from the more specific idea observed in his mother or father 
and in other persons to that of human nature. For in order 
to discern that he had not the precise idea of the individual, 
it is sufficient to consider that an ordinary resemblance would 
deceive him easily and make him take as his mother another 
woman. You know the story of the false Martin Guerre,^ who 
deceived even the wife of the true, and the near relatives, by 
resemblance united with skill, and embarrassed for a long 
time the judges, even when the true Martin had arrived.] 

§ 9. Ph. Thus this whole mystery of genus and species, 
which makes so much noise in the schools, but which outside 
of them is with reason so little regarded, this whole mystery, 
I say, reduces itself solely to the formation of abstract ideas 
more or less extended, to which certain names are given.- 

1 Cf. Essais de Theodic^e, Discours prelimiuaire, § 42, Gerliardt, 6, 74, 
Erdmanu, 491, b, Jacques, 2, 48. In the sixteenth century, Martin Guerre, a 
gentleman of Gascony, disappeared from home. After a long absence, a mau 
by the uame of Arnaud du Thil suddenly appeared, claiming to be Martin 
Guerre, and was acknowledged by the wife of Guerre as her husband. She 
had by him two children. Learning, afterwards, that her true husband was 
in Flanders, she angrily delivered the impostor into the hands of justice. The 
long trial, one of the most celebrated cases of the century, was brought to an 
end by the sudden and unexpected arrival of the true Martin Guerre, and 
Du Thil was sentenced to death. For further details, and tlie sentence in full, 
cf. P. Larousse, Grand Diet. Universel de X/X« Steele, Vol. 8, p. 1603, b, c. 
A parallel case in recent times was the Tichborne trial in England. — Tr. 

2 The philosophies of Locke and Leibnitz present a sharp contrast on the 
question of genera and species, and the real existence of the universal. Accord- 
ing to Locke, the question is a wholly empty one, an inheritance from the 
un])r()fitable discussions of scholasticism. The general term, the universal, is 
a purely subjectiA^e product of the more or less arbitrary activity of man in 
abstraction, and has nothing whatever to do with reality. Leibnitz maintains 
that the universal is the inner essence of things, and that the formation of 



CH. Ill] ON HUMAN UNDERSTANDING 311 

Th. [The art of classifying things into genera and species 
is of no little importance and of much use both to the judg- 
ment and the memory. You know how important this is in 
botany, not to speak of animals and other substances, and 
without mentioning also beings moral and notional,^ as some 
call them. Order largely depends upon it, and many good 
authors so write that their entire discourse can be reduced to 
divisions and subdivisions, according to a method which has 
some relation to genera and species, and is of use not only in 
retaining things, but also in finding them.^ And they who 
have arranged all sorts of notions under certain titles or pre- 
dicaments subdivided have done a very useful tiling.] 

§ 10. Ph. In defining words, we avail ourselves of the genus 

general terms is not a mere thought-expedient, but a legitimate and proper 
appreliension of the true and the real. Cf. G. Hartensteiu, Locke's Lehre v. d. 
menschl. Erkenntniss in Vergleichung in. Leibniz's Kritik derselben, V., 
pp. 52 sq., also in his Histor. Philos. Ahhandl., Leipzig, 1870, pp. 1G2 sq. — Tr. 

1 Notional or couceptional beings, he(jriffliche TFe.sen, entia rationis, are 
those which, as Scliaarschmidt says, " serve to indicate tliat which witliout 
being in the ordinary sense of tlie word substantial (first substance in the 
language of Aristotle," cf. C'atcf/or. 5, 2^, 11 ; Wallace, Outlines of the Philos. 
of Aristotle, § 10, p.25 ; Zeller, Philos. d. Griech., II., 2 [Vol. 4], p. 304 sq., 3d ed., 
1879; but cf. also, Metaphys. VII., 7, 1032b, 2; Wallace, op. cit. § 34, p. 67, 
Zeller, op. cit. II. 2 [Vol. 4], p. 344 sq.) " can still lay claim to an ideal reality." 
For further discussion of the subjects of this and the note next preceding, 
cf. Neiv Essays, Bk. III., chaps. 5, 6, Bk. IV., chaps. 4, 6. — Tr. 

2 Cf. Gerhardt, Leibniz, philos. Schrift. 7, 67: " Fuere tamen autores non 
contemuendi, qui methodum rebus junxere vit Theodorus Zwingerus, Job. 
Thomas Freigius, Barthol. Kecliermannus, et diligentissimus Joh. Henr. 
Alstedius, cujus Encyclopaedia mihi pro captu illorum temporum laudanda 
videtur." Alsted, 1588-1638, was Professor of Philosophy and Theology at 
Herborn in Nassau, but applied himself chiefly to systemizing the several 
branches of art and science. His Encyclopsedia,HerhoTmTe,lCM0,7 \o\s.,iol., 
reprinted Lugduni, 1C49, 4 vols., fol. Leibnitz often mentions it ('•/'. G. 4, 62, 
74, E. 22, a, 28, b; Dutens, Leibnit. opera omnia, 5, 405, 567), and wrote down 
some thoughts — cof/itata quxdam — for its enlargement and improvement; 
cf. Dutens, 5, 183-185. The classified contents of the work are given in the 
article "Encyclopaedia," in the Encyclop. Brit. 9th ed., Vol. 8, p. 17(!, I> 
(American Reprint). Schaarschmidt states that the different works of K. 
Goclen, as well as those of Alsted, are of the kind alluded to in the text. 
Goclen, 1,547-1626, was Professor of Philosophy at Marburg, and published a 
Lexicon philosophicnm, Marburg, 1613, 1 vol., 4to, which, though of little 
value, enjoyed from its novelty considerable celebrity at the tinu' of its ;i|)pear- 
ancc. l-i-ibnitz refers to this woi'k in his third Icltcr to Clarke; 'f. G. 7, 365, 
E. 752, b, J. 2, 426, D. 2, 122. Goclen was the 'discovc'rer and signalizer' of 
the Inverse, Regressive, or Goclenian Sorites, in comprehension ; <f. Hamilton, 
Lects. on Loi/ic, XIX., p. 27.'!, Amer. ed., and Goclenii Isayoge in Oryanum 
Aristotelis, p. 255, Francof. 1598. — Tu. 



312 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

or the next general term ; and this is for the purpose of spar- 
ing ourselves the trouble of counting the different simple ideas 
which this genus signifies, or sometimes perhaps for the pur- 
pose of sparing ourselves the disgrace of being unable to make 
this enumeration. But although the shortest way of defining 
is by means of genus and difference, as the logicians say, it may 
be doubted, in my opinion, whether it is the best ; at least it 
is not the only way. In the definition which states that man 
is a rational animal (a definition which is perhaps not the 
most exact, but which serves well enough the jjresent pur- 
pose), instead of the word animal you might put its definition. 
And this shows the little necessity of the rule which requires 
that a definition must he composed of genus and difference,^ and 
the little advantage there is in its strict observance. Thus 
languages are not always made according to the rules of logic, 
so that the meaning of each term may be exactly and clearly 
expressed by two others. And those who made this rule have 
done ill in giving us so few definitions conformable to it. 

Th. [I agree with your remarks ; it would be advantageous, 
however, for many reasons, if definitions might consist of tn-o 
terms : it would without doubt greatly shorten them, and all 
divisions could be reduced to dichotomies which are the best 
species of divisions, and are particularly useful for invention, 
judgment, and memory. I do not, however, think logicians 
always demand that the genus or the difference be expressed 
in a single word ; for example, the term regular polygon may 
pass as the genus of the square, and in the figure of the circle 
the genus might be a plane curvilinear figure, and the dif- 
ference might consist in the fact that all points of the circum- 
ference are equally distant from a certain point as centre.^ 

1 Cf. Aristotle, Topica, VI., 4, Mlb, 26: Set ii.kv SiaroO yivov^ koj. rSiV SLa<f>opS>v 
opi^eaOaL rbi' (caAjJs optfo^iei-or, also I., 8, IDS'*, 15 '. fVeiSJ) 6 6pt<r/a6s ex -yeVous Koi. Sia<}>opuiv 

ecjTiV, aud Wallace, Outlines, §§ 14, 15, 25; Zellev, Fhilos. d. Griec/t., U., 2 
[Vol. 4], p. 255. — Tr. 

2 Leibuitz rightly takes exception to Locke's censure of Aristotle's rule 
regarding definition, given in the preceding note, viz. : that it must consist of 
the genus and the species-forming difference, remarking that genus and dif- 
ference may verj' often he interchanged, the ijossibility of this interchange 
depending upon the principle on which, or the point of -^iew from which, the 
classification is made, or upon the closeness with which the genus and the 
species-forming difference approach each other, it being essential to valid 
interchange that they be actually alike, or so nearly so that the difference is 



cii. Ill] ON HUMAN UNDERSTANDING 313 

For the rest, it is also well to remark that very often the genus 
may be changed into a difference and the difference into a 
genus. For exam2)le, the sqnare is a regular cxuadrilateral, or 
rather a four-sided figure that is regular, so that the genus 
or the difference seems to differ only as the substantive and 
adjective ; as if, instead of saying that man is a rational living 
being {animal raisonnable) , language allowed the statement 
that man is a living rational being {rational animahle), i.e. 
a rational substance endowed with an auimal nature ; while 
genii ^ are rational substances whose nature is not animal or 
common with the animals. And this interchange of genera 
and differentia depends upon the variation of the order of the 
sub-divisions.] 

§ 11. Ph. It follows from what I have just said, that what 
is called general and universal belongs not to the being (exist- 
ence) ^ of tilings, but that it is a work of the understanding, 
§ 12, and the essences of each species are only abstract ideas. 

Th. [I do not quite see this consequence. For generality 
consists in the resemblance of separate things among them- 
selves, and this resemblance is a reality.] 

§ 13. Ph. I was going myself to say to you that these species 
are founded upon resemblances. 

Th. [Why, then, not seek therein also the essence of genera 
and species ?] 

§ 14. Ph. You will be less surprised to hear me say that 
these essences are the work of the understanding, if you con- 
sider that there are at least complex ideas which in the minds 
of different persons are often different collections of simple 
ideas, and thus what is avarice in the mind of one man is not 
so in the mind of another. 

practically of no account. Cf. New Essays, Bk. III., chap. 3, ante, p. 308. 
Such definitions, while not strictly logical or scientific in the full sense of these 
terms, hut tentative rather, and, as it were, popular, are nevertheless useful, 
and indeed necessary, in ordinary life and in science, where we must classify 
to a certain extent for tlie sake of relative clearness, hut where strict logical 
definition is not essential, or is impossihle hecause of the insufiiciency of our 
knowledge. Logically exhaustive definition, save in the r(!alin of pure thought 
and in such sciences as the pure mathematics, is possihle only to an infinite 
mind wlio possesses exhaustive knowledge of all principles and facts involved. 
Exhaustive knowledge of an individual demands an exhaustive knowledge of 
all other individuals. Cf. N. E., Bk. III., chap. :!, § G, TJi., ante, p. 309.— Tr. 

1 I.e. angels and archangels. — Tr. 

2 Locke has : " real existence," Philos. Wks., Vol. '1, p. 14 (l5ohn's Ed.). — Tii. 



314 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

Til. [I admit, sir, that there are few cases in which I have 
less understood the force of your inferences than here, and 
this troubles me. If men differ in the name, does it change 
the things or their resemblances ? If one applies the name 
avarice to one resemblance, and another to another, there will 
be two different species designated by the same name.] 

Ph. In that species of substance which is most familiar to 
us and with which we are most intimately acquainted, it has 
many times been doubted whether the offspring brought into 
the world by a woman was a man,^ even to discussing whether 
he should be fed and baptized. This could not be if the ab- 
stract idea or the essence, to which the name man belongs, 
were the work of nature, and not a diverse, uncertain collection 
of simple ideas which the understanding put together, and to 
which it attached a name, after having made it general by 
way of abstraction. So that at bottom each distinct idea, 
formed by abstraction, is a distinct essence. 

Th. [Pardon me for telling you, sir, that your language 
perplexes me, for I do not see its connection. If we cannot 
always discern by the outside the internal resemblances, are 
there less of them in nature ? When we doubt whether a 
monster is a man, we doubt whether it has reason. When we 
know it has, the theologians will order it to be baptized, and 
the jurisconsults, to be fed. It is true that we may dispute 
about the lowest species logically considered, which vary 'by 
accidents in one and the same physical species, or species by 
direct descent {tribu de generation),"^ but we do not need to 
determine these ; we may, indeed, vary them infinitely, as is 
seen in the great variety of oranges, lemons, and citrons, which 
experts know how to name and distinguish. The same thing 
was seen in tulips and pinks when these flowers were in 
fashion. For the rest, the fact that men unite these or those 
ideas, or even that nature actually unites them or not, makes 
no difference as regards essences, genera, or species, since the 
question only concerns possibilities, which are independent of 
our thought.] 

1 Cf. Locke, Philos. Works, Vol. 2, p. 17, and note (Bohn's Ed.). — Tr. 

2 Cf. New Essays. Bk. III., chap. 6, § 14, Gerbardt, 5, 28S, line 14 ; Erdmann, 
313, a; Jacques, 1, 234. The term "species," in Leibnitz's day, denoted not 
merely similarity of external form and characteristics, but more essentially 
the genetic relationship of common descent. — Tr. 



cii. Ill] ON HUMAN UNDERSTANDING 315 

§ 15. Ph. The species of each thing is ordinarily supposed 
to have a real constitution, and it is beyond doubt that some 
real constitution must exist vipon which every collection of 
simple ideas or qualities co-existing in this thing must depend. 
But as it is evident that things are ranked in sorts or species 
under certain names only as they agree with certain abstract 
ideas to which we have attached these names, the essence of 
each genus or species comes thus to be nothing else than the 
abstract idea signified by the general or specific name, and we 
shall find this to be the import of the word essence, according 
to its most ordinary use. It would not be a bad thing, in my 
opinion, to designate these two kinds of essences by two 
different names, and to call the one real, and the other, nominal 
essence. 

Th. [It seems to me that our language makes extreme inno- 
vations in the method of expression. We have indeed spoken 
hitherto of nominal and causal or real definitions, but not 
within my knowledge of essences other than real, at least by 
nominal essences have not been understood false and impos- 
sible essences, which appear to be essences, bu.t are not; as, 
for example, would be that of a regular decahedron, i.e. of a 
regular body comprised within ten planes.^ Essence is at 
bottom nothing less than the possibility of that which we 
think. What we assume as possible is exj)ressed by the defi- 
nition; but this definition is only nominal when it does not 
express at the same time, possibility ; for then we may doubt 
whether this definition expresses anything real, i.e. possible, 
until experience comes to our aid to make i;s know this reality 
a posteriori,^ when the thing is actually found in the world : 
and this sulfices for the defect of the reason, which made us 
know the reality a priori ^ by exposing the cause or the possible 
generation of the definite thing. It does not then depend on 
us to unite ideas as seems good to us ; at least, this combination 
is not justified either by reason which shows it as possible, or 
by experience which shows it as actual, and consequently, also 
possible. In order the better to distinguish, also, essence and 

1 This figure is impossible, the only possible regular polyhedrons being 
tlie tetrahedron, hexahedron, octohedron, dodecahedron, and icosahedron. — 
Tr. 

2 Cf. ante, p. 227, note 2. — Tr. 



lllli LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

definition, 3^011 must consider that tliere is only one essence of 
the thing, but that there are many definitions which express 
one and the same essence, as the same structure or the same 
city may be represented by different scenographies according 
to the different sides from which it is regarded.] 

§ 18.^ Ph. You will, I think, agree with me that the real 
and the nominal are always the same in simple ideas and in 
the ideas of the modes ; but in the ideas of substances, they 
are always entirely different. A figure which bounds a space 
by three lines is the real as well as the nominal essence of 
the triangle ; for it is not only the abstract idea to which the 
general name is annexed, but the essence or proper being of 
the thing, or the foundation whence proceed its properties, 
and to which they are annexed. But it is wholly otherwise 
as regards gold. The real constitution of its parts, upon which 
its color, weight, fusibility, firmness, etc., depend, is unknown 
to us ; and, having no idea of it, we have no name that is its 
sign. Yet these are the qualities which cause the matter to 
be called gold, and are its nominal essence, i.e. which give it a 
right to the name. 

Th. [I should prefer to say, in accord with received usage, 
that the essence of gold is that which constitutes it and which 
gives it these sensible qualities, which make it known and 
which make its nominal definition, while we should have the 
real and causal definition if we could explain this contexture 
or internal constitution. But the nominal definition is here 
found real also, not by itself (for it does not make known 
a priori the possibility or the genesis of bodies), but by experi- 
ence, because we have experience of a body in which these 
qualities are found together : but without this we might doubt 
whether so much weight would be compatible with so much 
malleability, as it may be doubted, even at present, whether a 
glass malleable by cold is possible in nature.^ I am not, for 
the rest, of your opinion, sir, that there is here the difference 

1 § 18, in Locke, Philos. Works, 2, p. 19 (Bolin's ed.) ; so Gerhardt : Erdmann, 
Jacques, and Schaarschmidt in his German translation, have § 19. — Tr. 

2 Cf. Pliny the Elder, 23-79, Histor. Natur., Bk. 36, chap. 66; Eng. trans. 
(Bohn's Class. Lih.), Vol. 6, p. 381, London, 1857. " In the reign of Tiberius, 
it is said, a combination was devised which produced a flexible glass. . . . This 
story, however, was, for a long time, more widely sprijad than well authenti- 
cated " — " fama crebrior quam certior." — Tr. 



cii. Ill] UN HUMAN UNDERSTANDING 317 

between the ideas of substances and the ideas of predicates, as 
if the definitions of predicates (i.e. of the modes and the 
objects of simple ideas) were always real and nominal at 
the same time, and that those of substances were only nominal. 
I quite agree that it is more difiicult to have real definitions 
of bodies, which are substantial existences because their con- 
texture is less sensible. But it is not the same with all sub- 
stances ; for we have a knowledge of true substances or unities 
(as God and the soul) as intimate as we have of the most of 
the modes. Besides, there are some predicates as little known 
as the contexture of bodies ; yellow or bitter, for example, 
are objects of simple ideas or notions (phantasies^), and yet we 
have only a confused knowledge of them.^ The case is the 
same in mathematics, where one and the same mode may have 
a nominal as well as a real definition. Few people have 
clearly explained in what consists the difference between these 
two definitions which must distinguish, also, essence and prop- 
erty. In m.y opinion, this difference is that the real shows 
the possibility of the thing defined, and the nominal does not.^ 

1 Schaarschmidt translates : " die Gegenstande einfacher Vorstellimgen oder 
Phantasiebilder." — Tr. 

2 Cf. Neio Essays, Preface, wite, p. 48, ad fin, and Bk. IV., chap. 6, § 7, Th. 
(2), j«/Va,p. 458. According to Leibnitz, sense-knowledge is confused, and needs 
to be developed into clearness and consistency by the discriminative analysis 
and unifying power of thought. Phenomena such as colors, sounds, etc., the 
subjective countei'ijart or resultant of specific sense-energies, resist all further 
analysis, and while clear as wholes, are composite, insoluble, and so confused 
as regards their single elements. Such wholes admit only descriptive, not, 
strictly speaking, logical definition. Cf. Med. de C'of/., Ver., et Id. ad init., 
Gerhardt, 4. 422, Erdmann, 78, a, trans. Duncan, Philos. Works of Leibnitz, 27. 
— Tr. 

3 Cf. ante, pp. 17, 201, and Med. de Cog., Ver., et Id., Gerhardt, 4, 424, 
Erdmann, 80, 1), trans. Duncan, Philos. Works of Leibnitz, 30; also G. G, 
405, E. f)37, a, Dutens, Leibnit. opera omnia, 1, 439; 6, 44; G. 7. 194 and note. 
As the nominal definition explains a thing according to the name, we may have 
nominal definitions of objectively non-existent or of impossible tilings, as 
centaurs, griffins, or any of the creatures of the fancy or the imagination, or 
the decahedron mentioned in § 15, Th., of this chapter, ante p. 315. The real 
definition explains the thing to be defined by exhibiting its cause or generation, 
its rise out of its conditions, i.e., its possibility; it is thus identical with the 
genetic definition, and Leibnitz accordingly calls it the causal definition, ante 
p. 31(i. Cf. also Dewey, Leibniz's New Essays, 210; Hamilton, Locjic, 343; 
Trendelenburg, Ueber d. Element d. Definition in Leibniz. Philosophie in 
Histor. Beitr. z. Philos., Berlin, 18()7, Vol. 3, pji. 48-()2. Trendelon))nrg calls 
special attention to the fact tliat Leibnitz, in drjinition, has in mind (^specially 
the analytical element, explaining definition as an unfolding of the concept, 



818 LEI13^'1TZ"S CRITIQUE OF LOCKE [bk. in 



The definition of two jjandlel straight lines, which states that 
they are in one and the same plane and will not meet although 
continued to infinity, is only nominal, for we could at once 
doubt whether that is possible. But when we have under- 
stood that we can draw a straight line in a plane parallel to 
a given straight line provided w^e take care that the point of 
the style describing the parallel remains always equally distant 
from the given line, we see at once that the thing is possible, 
and why they have this property of never meeting, which con- 
stitutes their nominal definition, but which is the sign of the 
parallelism only when the two lines are straight, while if one 
at least were curved, they might be by nature unable ever to 
meet, and yet not on that account be parallel. 

§ 19. Ph. If essence was something else than the abstract 
idea it would not be ingenerable^ and incorruptible. A uni- 
corn, a mermaid, a perfect circle, perhaps do not exist in the 
world. 

TJi. [I have already told you, sir, that essences are perpetual, 
because here the question concerns only the possible.] 



CHAPTER IV 

OF THE NAMES OF SIMPLE IDEAS 

§ 2. Ph. 1 confess I have always believed that the forma- 
tion of the modes was arbitrary ; but as regards simple ideas 
and those of substances, I have been persuaded that, besides 
possibility, these ideas should signify a real existence. 

T/i.<^f I see no necessity for it. God has ideas before creating 
the objects of these ideas, and nothing prevents Him from 
being able also to communicate such ideas to intelligent creat- 
ures : there is also no exact demonstration proving that the 
objects of our senses and of the simple ideas which the senses 

or its resolution into several concepts equivalent to the one concept — •" definire 
est explicare notionem, resolvere in plures uotiones uni aequivalentes ; " cf. 
Dutens, 0^3. C(i.,4, 68 : " defiuitio niliil aliud, quani accurata nominis explicatio 
est"; G. 4, 140, E. 60, b : "definitio enini nihil aliud est, quam signiticatio 
verbis expressa, sive brevius, significatio signiticata." — Tr. 

1 Locke's word, Philos. Works, Vol. 2, p. 20 (Bohn's ed.). — Tr. 



cii. IV] ON HUMAN UNDERSTANDING 319 

present to us are outside us.^ This fact has especial weight 
in the case of those who believe with the Cartesians and with 
our distinguished author, tliat our simple ideas of sensible 
qualities have no resemblance to tliat which is outside us in 
the objects ; there would then be nothing requiring these ideas 
to be grounded in any real existence.-] 

§§ 4, 5, 6, 7. Ph. You will grant me at least this other 
difference between simple and complex ideas, that the names 
of simple ideas cannot be defined, while those of complex ideas 
can be. For definitions should contain more than one term, 
each of which signifies one idea. Thus you see what can or 
cannot be defined, and why definitions cannot go on to infinity; 
a remark which no one, so far as I know, has up to this time 
made. 

Th. [I have also made the statement in the brief Essay 
upon Ideas,^ inserted in the " Actes de Leipzic " about twenty 
years-^ince, that simple terms cannot have nominal definitions ; 
but I have there added at the same time the statement that 
terms, when they are simple only as regards us (because we 
have no means of analyzing them so as to reach the elementary 

1 The demonstrability of the reality of that which lies at the basis of the 
phenomena of the senses is one of the most diflficult problems in the theory of 
knowledge — Erkenntnisslehre. Leibnitz seems nowhere to have discussed the 
question, at least in this form, nor to have asked himself how, agreeably to 
his philosophical system, a knowledge of the reality of the external world 
could be demonstrated or a belief therein justified. So far as his system sug- 
gests any answer consistent with itself, that answer is found in his doctrine of 
pre-established harmony, in the consciousness of w^hich we pass immediately 
from our inner representative world of ideas to belief in the reality of the 
external things thus ideally represented. This, however, like Descartes' 
attempt to bridge the chasm from the subjective to the objective liy his doctrine 
of God's veracity, is mere assumption, not " exact demonstration." The 
jiroblem belongs to both psycliology and metaphysics, and is satisfactorily 
discussed and solved oidy when considered in these two aspects. Leibnitz was 
an idealist in psychology, and a realist in metaphysi('s, and never really har- 
monized or united these two points of view. For him, therefore, there could 
be ''no exact demonstration" of the external reality of "the objects of our 
senses and of the simple ideas whicli the senses present to us." Cf. Discours 
de Metnphysiqur, §§ 21) sq., Gerhardt, Leibniz, philos. Hchrift., 4. 451 sq., E. 
Caird, The Crit. Philo.s. of Immunuel Kant, 1, 8G-95. New York, Macmillan 
&Co., 1889. — Tr. 

2 Cf. Nev) Essays, Bk. XL, chap. 8, §§ 21, 24, ante, pp. 1.3:5-135 ; also Bk. IV., 
chap. 11. The constancy of sense-phenomena is the constraining reason for 
referring them to something real. Cf. Dewey, Leibniz's New Essays, 173 sq.; 
Gerlianit, Leibniz, pli Has. Srhrift. 7, 319 .tq. — Tii. 

3 Cf. ante, p. 14, note 2 ; p. 227, note 3. — Tb. 



320 LEIBNITZ'S CKITIQUE OF LOCKE [bk. hi 

perceptions of which they are composed), as heat, cold, yellow, 
green, can receive a real definition which would explain their 
cause. Thus, the real definition of green is that of an entity 
composed of blue and yellow thoroughly mixed,^ although 
green is no more susceptible of a nominal definition by which 
we may recognize it than blue or yellow. Terms on the other 
hand which are simple in .themselves, i.e. whose conception is 
clear and distinct, cannot receive any definition, whether 
nominal or real. Yoii will find in this little Essay, placed in 
the "Actes de Leipzic," the foundations of a large part of 
the doctrine concerning the understanding, briefly explained.] 

§§ 7, 8. Ph. It were well to explain this point and to indi- 
cate what can be defined, what not. And I am tempted to 
believe that often great disputes are raised and much nonsense 
introduced into men's discourse from a failure to consider this 
matter. These celebrated trifles about which so much stir is 
made in the schools have arisen from the fact that no attention 
has been paid to this difference which is found in ideas. The 
greatest masters in the art have been constrained to leave 
the majority of simple ideas without defining them, and when 
they have undertalven to define them, they have not succeeded. 
What more superfine nonsense, for example, could the mind of 
man invent than that which is contained in this definition 
of Aristotle : Motion is the realization of that which is possible 
so far as it is possible ?^ § 9. And the moderns who define 
motion as passage from one place into another, merely put one 
synonymous word in the place of another. 

Th. [I have already remarked in one of our past conferences 
that you consider many ideas as simple which are not so. 
Motion is of this number which I believe to be definable ; and 
the definition which states that it is a change of place is not 
to be despised. Aristotle's definition is not so absurd as you 

1 This is true of pigments, but uot of lights. Blue and yellow lights when 
mixed produce white light. — Tr. 

2 Cf. New Ess(t[/s, Bk. II., chap. 21, § 1, Th. ante, -p. 174. For Aristotle's 

definition, cf. PhyS. AcrOUS., III., 1, 201b, 4; ij toO Swarov, jj Swoltov, ivreKixna 
(paviphv oTi kiVtjctis etrrii', 201^^, 11 : V ^"P Swifiei ovTOS ivTe\e\ei.a, fi roLOvTOV, (ciyrjo-is 
ecTTii', Metaphys. K, 9, 1065^, 16 : Trjv toO hwaim fi toioCtov eanv ivepyiav Ae'yio 
KLi'y]aLi\ 23 I V ^V ''"0^ Svvd^et ovTO?, OTav evTcXexeCa ov evepyrj 7j avTO rj dAAo tj Kii'TJTOVf 

Kii'7)(Tis ea-Tiv, also 33 ; Wallace, Outlines of the Philos. of Aristotle, § 42, p. 77 ; 
Zeller, Philos. d. Griec, 3d ed., 1879, II., 2 [Vol. 4], p. 350 sq., with the notes 
-Til. 



CH. IV] ON HUMAN UNDERSTANDING 321 

tliink, this supposed absurdity arising from the failure to 
understand that the Greek KtV/yo-t? Avith him did not signify 
what we call motion, but what Ave would express by the word 
change, whence it comes that he gives it a definition so abstract 
and meta})liysical, while Avhat Ave call motion is called by him 
^opd, latio, and is found among the species of change (r^s 

Ktvrjcrew'i ).J 

§ 10. Ph. But you Avill not apologize, at least, for the same 
author's definition of light as the action of the transparent.' 

Th. [I find it, as you do, very useless ; ^ and he makes too 
frequent use of his action, which does not tell us much. 
Dicq^hanous is for him a medium across Avhich Ave can see ; 
and light is, according to him, that Avhich consists in the 
actual passage. Well and good.] 

§ 11. Ph. We agree, then, that our simple ideas cannot 
have nominal definitions, as Ave cannot know the taste of pine- 
apples by the accounts of travellers, unless able to taste things 
by the ears, as Sancho Panza had the power to see Dulcinea by 
hearsay,"* or as that blind man who, having been heard to speak 
boldly of the brilliancy of scarlet, thought it must resemble 
the sound of the trumpet. 

Th. [You are right; and all the travellers in the world 

1 Cf. Phys. Acroas., VII. 2, 243'', 6 sq. : end Se rpei? eicrX Ktfijo-ei;, rj t6 Kara tottov 
Kai Kara to ttocoj' Kat KaT<i to ttoctoi', ai'dyKr) Kai to. Kivovfj.ei'a Tpt'a, 17 fxey oir KaTo. tottoi' 
<j>opd, 17 5e Kara, to Trotbr aAAot'tuo't?, i] 6e KaTo. to tto<t'oi' au^rjat? Kat tjiOiai';, EtJl, ^ic. X., 

3, 1174^, 30: ei yap iari-v rj ^opd Ktfr)(ri,s TrdSei' irol (Alex. Grant, The Ethics of 
Aristotle, Vol. 2, p. 324, line 17, 3d ed., London: Longmans, Green, & Co., 
1874); Wallace, Outlines. § 42; Zeller, Fhilos. d. Griec., 3d ed., 1879, II., 2 
[Vol. 4], p. 389S7. — Tr. 

^ Cf. De Aniina, XL, 7, 418'*, !): <J>m^ &e etrnv 17 toutou ivepyna ToO Siaijiavovi fj 
Sia4>aves, 419*, 11 : ») S' evTeAexeia toD Siaipavov^ (j>u)^; eariv. E. Wallace, AristOtle's 

Psychology in Greek and Enr/lish iv. Introd. and Notes, Cambridge : Univ. 
Press, 1882, pp. 95, 97, translates the two passages: " Liglit tlien is the expres- 
sion of the pellncid qua pellucid," "The full play of this pellucid constitutes 
light," and, in his Introd., p. lxxi.,comljines them tlius : " Liglit therefore may 
itself be defined as tlie actual expression or full play of the pellucid as pellucid." 
Cf. also Zeller, Philos. d. Griec, 3d ed., 1879, II. ,2 [Vol. 4], p. 477, note 2. 

3 Schaarschmidt calls attention to "a bad typograpliical error" in tlie text 
of Raspe's eilition of the Nouveaux Essnis at tliis point. Raspo ri'ads " fort 
ufcile," for whicli Scliaarsclimidt proposes "futile." Gerliardt, Erdniann, and 
Jacques all read " fort inutile," which gives the requisite sense, and is accord- 
ingly followed in the translation. — Tr. 

■» Cf. Cervantes, 1547-1G16, Don Quixote, Pt, 2, chap. 9, ad med. ; also, Pt. 1, 
chap. 31. — Tr. 

Y 



322 LEIBNITZ'S CRITIQUE OF LOCKE [luc. in 

could not give by their words what we owe to a gentleman 
of this country who cultivates successfully pine-apples three 
leagues from Hannover, almost upon the bank of the Weser, 
and who has found means of multiplying them to such an 
extent that some day we can perhaps have them of our own 
growing in as great abundance as the oranges of Portugal, 
thoiigh there would apparently be some loss in the flavor.] 

§§ 12, 13. Ph. It is wholly otherwise with complex ideas. 
A blind man can understand what a statue is ; and a man who 
had never seen the rainbow could uiaderstand what it is, pro- 
vided he had seen the colors which comj)ose it. § 15. But 
tliough simple ideas are inexplicable, they are the least doubt- 
ful. [For experience accomplishes more than definition.] 

Th. [There is, however, some difficulty as to the ideas which 
are only simple as regards us. For example, it would be diffi- 
cult to indicate precisely the limits of blue and of green, and in 
general to discriminate colors closely approaching one another, 
while we can have precise notions of the terms used in arith- 
metic and geometr}'-.] 

§ 16. Ph. Simple ideas have further this peculiarity that 
they have very little subordination in what the logicians call 
the line of predication {ligne predicamentale),'^ from the lowest 

1 Leibnitz here refers to the Tabula logica, in which Porphyry, 233-304, and 
after him the Scholastic logicians, snch as Lambert of Auxerre, c. 1250, Petrus 
Hispauus, c. 122(5-1277, Raimnnd Lulli, 1234-1315, the Pseudo-Thomas, and 
Johannes Majoris Scotus, 1478-1540, sought, in connection with the five pre- 
dicables, to arrange in strict logical subordination by the process of dicho- 
tomic or bifurcate division, all genera and species from the highest genera to 
the lowest species, between which is found the scale of subordinate notions 
which are at the same time both genus and species. This Tabula loc/ica was 
called by the later commentators, who added the diagram illustrating it, not 
found in Porphyry, the arbor Porphyriana ov the arbor pracdicamoitalis, and 
the line of subordination from the highest genus to the lowest species was called 
the Ihiea praedicamentalis or praedicabilis, or the ordo jiraedicamentalis. Cf. 
Porphyry, Eicravwy^ chap. 2, 1 b. 40 sq. (in Aristotle, ed. Berl. Acad., Vol. 4, 
p. 1) ; 'Ef'JYio-'?, f. 18 b., Paris, 1543, 4to ; Prantl, Gesch. d. Loc/ik im Abend- 
lande, Leipzig, 1855-1870, Vol. 1, pp. 627-8, note 41, 63.3-4, note 67, Vol. 3, pp. 
28, note 14: "Praedicaraentum autem nihil aliud est, quam ordinatio prae- 
dicabilium in linea praedicabile secundum sub et supra et a latere et in linea 
recta, . . . unde ilia tota ordinatio, quae est inter genus generalissiraum et 
speciem specialissimam et genera subalterna et differentias collaterales, voca- 
tur unum praedicam«ntum, sicut patet in arbore Porphyrii in tractatu Prae- 
dicabilium." (Lambert of Auxerre, Summa logicae, Paris, MS., Cod. So7-bonn. 
1707), 46, note 168, 151, note 42, 252, note 315, cf. n. 311, Vol. 4, p. 249, note 
434 ; also, Jevons, Elementary Lessons in Logic, p. 103 57. — Tr. 



CH. IV] ON HUMAN UNDERSTANDING 323 

species to tlie highest genus. The reason is that the lowest 
species being only a simple idea, nothing can be taken from 
it ; for example, nothing can be taken from the ideas of white 
and red in order to retain the common appearance in which 
they agree. For this reason, they are included with yellow 
and others, under the genus or the name, color. And when 
men wisli to frame a still more general term, comprising, also, 
sounds, tastes, and tangible qualities, they avail themselves of 
the general term, quality, in the sense ordinarily given it to 
distinguish these qualities of extension, number, motion, pleas- 
ure, and pain, Avhich act upon the mind and introduce into it 
their ideas by more than one sense. 

Th. [I have something more to say upon this remark. I 
hope that here and elsewhere you will do me the justice, sir, 
to believe that this is not from a spirit of contradiction, 
and that the subject seems to demand it. It is not an advan- 
tage that the ideas of sensible qualities have so little subordina- 
tion and are capable of so few subdivisions ; for it arises only 
from the fact that we know little of them. But the fact itself 
that all colors have the common property of being seen by 
the eyes, of all passing into bodies from which one or more 
of them reappear, and of being reflected from the polished 
surfaces of bodies which do not allow them to pass, shoAvs us 
that something can be taken from the ideas we have of them. 
Colors may indeed be divided with good reason into extremes 
(one of which is 2)ositive, viz. white ; and the other privative, 
viz. black) ; and into means, which are called colors,^ however, 
in a particular sense, and which spring from light by refrac- 
tion ; which furthermore may be subdivided into those of the 
convex side, and those of the concave side of the broken ray. 
And these divisions and subdivisions are of not a little conse- 
quence.] 

Ph. Jjut how can you find genera in simple ideas ? 

Th. [As they are simple only in appearance, they are 
accompanied by circumstances which are bound up with tliem, 

1 Gerhard t r(!ads: " et en moyens qu'oii appelle encor couleurs dans un 
sens particulior et qui naissent de la lumierc par la refraction; qu'on pent 
eneor,'' etc. ; Erdmann and -Jacques read: " et en moyens qu'on appelle encore 
sous-diviser," etc. ; i.e. and into means which you are further called upon to 
subdivide, etc. — Tr. 



324 LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 

altliougli this bond is not understood by us, and these circum- 
stances furnish somewhat that is explicable and susceptible 
of analysis, which gives also some hope that hereafter the 
reasons of these phenomena may be discovered. Thus it 
happens that there is a kind of pleonasm in our perceptions of 
sensible qualities, as well as sensible masses ; and this pleonasm 
is, that we have more than one notion of the same subject. 
Gold may be defined nominally in several ways ; you may say 
that it is the heaviest of our bodies, that it is the most malle- 
able, that it is a fusible body which resists the cupel and aqua 
fortis, etc. Each of these marks is good and is sufficient for 
the recognition of gold, at least provisionally and in the present 
state of our bodies, until a heavier body is found, as some 
chemists maintain is the case in their philosopher's stone, or 
until that Luna fixa ^ is shown, which is a metal said to have 
the color of silver, and almost all the other qualities of gold, 
and which Chevalier Boyle ^ seems to say he has produced. 
Thus you may say that in matters which we know only 
empirically, all our definitions are merely provisional, as I 
believe I have already remarked above. It is then true that 
we do not know demonstratively whether a color may not pos- 

1 Cf. Fratris Bosilii Valentini Bencdictlner Ordens Chymische Schrift., 
Hamburg, 1700, Pt. I., p. 272: " Weun das Gold seiner Anima auch verlustig 
wird / giebt es ein weiss Corpus und einen fixeii weisseu Gold-Leib / der von 
den sucbenden Studenten / und von den Jiingern der Kunst eine Luna Jixa 
getaufft und genannt wird ; " Pt. II., p. 381, Scbluss-Reden Fr. Basilii Valentini, 
Tract. 1, Sectio iii., De jNIagneta vulgi, § 3: "Mitdem Magnet und Antimonio 
wird auch eine Lunaflxa gemacbt / welcbe alsdann durcb das Oleum Martis 
& Veneris gradirt [sic] , und zu Gold gemacht wird : Jedoch kan mans mit 
Antimonio und Eisen aucb vei-ricbten." Martin Ruland, Lexicon alchemist, 
Francofurti, 1612, p. 308: "Luna compacta est argentum fixum vel aurum 
album: Silber fix oder weiss Gold." Robert Boyle, Works, ed. Birch, 5 vols., 
fol. : London, 1744, Vol. 1, p. 215; 2d ed., 6 vols., 4to : London, 1772, Vol. 1, p. 
335, Vol.3, p. 28. — Te. 

2 Robert Boyle, 1627-1091, a distinguished natural philosopher and chemist, 
the discoverer of the law of the compressibility of gases, which, confirmed by 
its independent discovery by Mariotte in 1676, has since been known as 
" Boyle and Mariotte's Law." He was one of the founders of the Royal Society 
of London, and by his will established the " Boyle Lectures." Leibnitz often 
refers to him, cf. Neio Essays, Preface, ante, p. 47. — The title of Boyle's work 
there referred to is. Of Absolute Rest in Bodies, Works, ed., Birch, 6 vols., 
4to, London, 1772, Vol. 1, pp. 443-457, in which he opposes the doctrine with 
convincing reasons;— Bk. IV., chap. 12, § 13, Th., infra, p. 526; Gerhardt, 
Leibniz philos. Schrift., 7, 342 ; Dutens, Leibnit op. orn., 5, 98: 6, 107; Leib- 
nitz's estimate of his experiments, 6, 318; Eulogy, 6, Pt. II., 217.— Tr. 



CH. V] ON HUMAN UNDERSTANDING 325 

sibly be produced, by reflection alone without refraction, and 
whether the colors we have hitherto noticed in the concavity 
of the angle of ordinary refraction are not found in the con- 
vexity of a kind of refraction hitherto unknown, and vice versa. 
Thus the simple idea of blue would be stripped of the genus 
Aviiich we have assigned it in our experiences. But it is well 
to stojj at the blue we have and at the circumstances attending 
it. And it is something that they furnish us the means of 
making genera and species.] 

§ 17. Ph. But what say you of the remark that has been 
made that simple ideas, since they are taken from the existence 
of things, are nowise arbitrary, while those of the mixed modes 
are wholly so, and those of substances to some extent ? 

Th. [I believe that the arbitrary quality is found only in 
the words, and not at all in the ideas. Eor they express 
only possibilities. Thus, if there had never been a parricide, 
and if all the legislators had been as cautious as Solon in 
speaking of it, parricide would be a possible crime, and its 
idea would be real. For ideas are in God from all eternity; 
and indeed they are in us before we actually think of them, 
as I have shown in our previous conversations.^ If any one 
wishes to take them as the actual thoughts of men, it is per- 
mitted him to do so, but he will oppose himself without reason 
to the accepted language. 



CHAPTER V 

OF THE NAMES OF MIXED MODES AKD RELATIONS 

§§ 2, 3, seq. Ph. But does not the mind form mixed ideas 
by bringing together simple ideas as suits its purpose, without 
the need of a real model ; while simple ideas arise for it 

1 Cf. New Essrq/.t, Preface, ante, p. 42, sq., Bk. I., chap. 1, § 1, sq., ante, 
p. 70, s(]., where Leibnitz develops more fully the tliouglit repeated here. 
Leibnitz assumes that ideas — the pure truths of reason— exist in man, and 
come into consciousness 1)y tlie self-developm(Mit of the spirit. These ideas 
contain in themselves the potential representation of all possible reality, the 
realization of which is directly proportional to tlie measure of man's self- 
development. In God this realization is complete, since iu his thought all 
real possibility is always at-tually represented. — Tr. 



826 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

without choice, through the real existence of things ? Is not 
the mixed idea often seen before the existing thing ? 

Th. If you take the ideas as actual thoughts, you are right. 
But I do not see that it is necessary to apply your distinction 
to that which concerns the form itself, or the possibility of 
these thoughts, and yet this is the question in the ide^l world 
which is distinguished from the existing world." The real 
existence of beings which are not at all necessary is a matter 
of fact or of history ; but the knowledge of possibilities and 
necessities (for necessary is that the opposite of which is not 
at all possible) constitutes the demonstrative sciences.^. 

Ph. But is there more connection between the ideas of 
killing and of man than between the ideas of killing and of a 
sheep ? Is parricide composed of more connected notions than 
infanticide ? And is it more natural that what the English 
call stabbing, i.e., murder by a thrust, or by striking with the 
point, which is a greater wrong with them than killing by 
striking with the edge of the sword, should have deserved a 
name and an idea which is not accorded, for example, to the 
act of killing a sheep, or of killing a man by cutting ? 

Th. [If the question concerns only possibilities, all these 
ideas are equally natural. Those who have seen sheep killed 
have had an idea of this act in thought, although they have 
not deigned to give it their attentio]i.- Why, then, limit our- 
selves to names, when the question concerns ideas themselves, 
and why occupy ourselves with the worth of the ideas of 
the mixed modes, when the question concerns these ideas in 
general ?] 

§ 8. Ph. Men form arbitrarily different kinds of mixed 
modes, so that words are found in one language for which 
there are no corresponding words in another. There are no 
words in other languages corresponding to the word Versura ^ 

1 Cf. JVeiv Essays, Preface, ante, p. 43. — Tr. 

2 Erdniann reads : " quoiqu'ils ne lui aieiit point donne de nom et ne I'aient 
point daigne de leur attention; " Jacques reads, after "daigne," " honorer," 
otherwise like Erdmann. Tlie rendering tlien is: altliougli they have not 
given it a name, nor have tliey vouchsafed (to honor — Jacques) it (with) 
their attention. — Tr. 

3 "Versura," literally "a turning round," means, in classical usage, "the 
borrowing of money to pay a debt," a process wliich resulted simply in 
changing one's creditor, not in extinguishing the obligation. Cf. Cicero, Epist. 



ni. v] ON HUMAN UNDEESTANDING 327 

used among the Eonians, nor to Corban,^ used by the Jews. 
We boldly translate the Latin words hora, lies, and libra, by 
hour, foot, and pound ; but the ideas of the Romans were very 
different from ours. 

Th. I see that many things which we discussed when the 
question was that of ideas themselves and their kinds, come 
hack now, under cover of the names of these ideas. The 
statement is true as regards the names and the customs of 
men, but it changes nothing in the sciences and in the nature 
of things. It is true that he who would write a universal 
grammar would do well to pass from the essence of languages 
to their existence, and compare the grammars of many lan- 
guages. In like manner, an author who should write a univer- 
sal jurisprudence drawn from reason, would do well to unite 
with it the parallel laws and customs of peoples, which would 
1)6 of service not only in practical life, but also in his reflec- 
tions, and would give him occasion to consider many points 
wluch would otherwise escape him. But in science itself, 
apart from its history or existence, it is of no consequence 
whether people are or are not conformed to the dictates of 
reason.] 

§ 9. Ph. The doubtful signification of the word species makes 
the statement that the species of mixed modes are made by 
the understanding offensive to some people. But I leave it to 
others to consider who fixes the limits of each sort or species, 
for these two words are for me wholly synonymous. 

ad Atticum, 5, 1.5, 2; Tacitus, Ann., 6, 10. As a proverb, the word means 
"to get out of one difficulty by getting into another." Cf. Terence, Phormio, 
5, 2, 15; Lactantius, 2, 8, 24. — Tr. 

1 "Corban," Hebrew f3']p, N.T. Kop^av, i.e. Supor, originally an offering to 
God of any kind, particularly in fulfilment of a vow. The original use was 
in coui-se of time altered by the traditionalists, and the offerer of the gift 
interdicted from using it for himself, or giving it to others. The " corban" 
furnished a ready means to any one who wished to relieve himself from any 
inconvenient obligation, as of assisting his parents in poverty or distress ; he 
simply brought his gift to the temple and offered it to God, saying, "Let it 
be corban," and departed free, as he said, from any further responsil)ility in 
the matter. It was this utter perversion of the spirit of the law, with its 
resultant positive wrong-doing, that Christ so severely rebuked. Cf. Mark 
7:11-1.'5; Matt. 15:.'), (!; and H. A. W. Meyer, Krit. K.tp(i. Ko7nmnrtar ii. d. 
N.T., fith ed., Guttingen, 187()— I., 2 [Vol. 2], p. 104; I., 1 [Vol. 1], p. .333; 
Smith's Diet, of the Bible, ed. Hackett and Abbot, New York, 1877, Vol. 1, 
p. 491. — Tr. 



328 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

Til. [The nature of things ordinarily fixes the limits of 
species; for example, of man and beast, of cut and thrust. I 
admit, however, that there are some notions in which the limit 
is truly arbitrary' ; for example, the question of determining a 
foot, for, the straight line being uniform and indefinite, nature 
indicates therein no limits. There are also essences, vague 
and im2:)erfect, into which op)iniou enters ; as when you ask 
how little hair must be allowed a man in order that he be not 
bald. This was one of the sophisms of the ancients, when one 
pressed upon his adversary: 

Dum cadat elusus ratione ruentis acervi.i 

But the true answer is that nature has not determined this 
notion, and that the opinion has its share therein that there 
are some persons regarding whom it may be questioned whether 
they are bald or not, and that there are some doubtful persons 
who will pass as bald with some and not with others, as you 
remarked that a horse which will be considered small in 
Holland, will pass as a large one in the country of the Gauls. 
There is indeed something of this nature in simple ideas, for 
I just observed that the final limits of colors are doubtful. 
There are also essences truly half-nomincd, in which the name 
enters into the definition of the thing ; for example, the degree 
or quality of doctor, chevalier, ambassador, king, is recognized 
when a person has acquired the recognized right to avail him- 
self of this name. And a foreign minister, however complete 
his power and however extended his train, will not pass as 
an ambassador unless his letter of credence gives him the 
name. But these essences and ideas are vague, doubtfid, arbi- 
trary, nominal, in a sense a little different from those which 
you have mentioned.] 

§ 10. Ph. But it seems that the name often conserves the 
essences of the mixed modes which you think are not arbitrary ; 
for example, without the name triumph, we should have but 
little idea of what took place among the Eomaus upon that 
occasion. 

Til. [I agree that the name serves to call attention to things 
and to conserve the memory and the actual knowledge of them ; 

1 Horace, Epist. 2, 1, 47. — Tr. 



CH. v] ON HUMAN UNDERSTANDING 329 

but that accomplishes nothing as regards the point in question, 
nor does it render the essences nominal ; and I do not under- 
stand why you gentlemen absolutely require that the essences 
themselves should depend upon the choice of names. It would 
have been desirable that your distinguished author, instead of 
insisting upon that, had preferred to enter into a much more 
detailed account of ideas and of modes, and to have set them 
in order and developed the varieties. I would have followed 
him on this road with pleasure and with profit. For he would 
doubtless have given us much light.] 

§ 12. Ph. When we speak of a horse, or of iron, we regard 
them as the things which furnish us the original patterns of 
our ideas ; but when we speak of mixed modes or, at least, 
of the most important of these modes, which are moral entities, 
— iox e,yi^m.iAe, justice, gratitude, — we consider their original 
modes as existing in the mind. Therefore we say the notion 
of justice, of temperance ; but we do not say the notion of a 
horse, of a stone. 

Th. [The patterns of the ideas of the one are as real as 
those of the ideas of the other. The qualities of the mind 
are not less real than those of the body. It is true you do 
not see justice as you see a horse, but you understand it no 
less, or rather you understand it better ; it is no less in acts 
than directness or obliqueness is in motions, whether you 
consider it or not. And to show you that men are of my 
opinion, and men, indeed, the most capable and most experi- 
enced in human affairs, I have only to avail myself of the 
authority of the Iloman jurisconsults, followed by all others, 
who call these mixed modes or these moral entities, things, 
and in particular, incorporeal things. For servitudes,^ for ex- 
ample (like that of the passage through the ground of one's 
neighbor), are with them res incorjyorales, in which there is a 
property which may be acquired by long use, and may be 
possessed and reclaimed. As for the word notion, many clever 
people have considered it as large as that of idea ; Latin usage 

1 Cy. Sandars, Institutes of Jvstininn, lAh. II., Tit. III., p. 118, 8tli od., 
London: Longmans, (Jreon, & Co., 1.SK8; Postc, Guiita, Kletncnts of Roman 
Law, Bk. II., 29, 31, pp. l(i5-(!, ;id cd., Oxford, 1890; Moninisen, Digest, Lib. 
VIII., 1, Vol. 1, p. 250, Berlin: Weidniann, 1870; Hadley, Introd. to Roman 
Law, pp. 158-1(51, 180-190, New York, D. Appletou & Co., 1881.— Tr. 



330 LEIIJNITZ'S CKITIQUE OF LOCKE [p.k. 



is not opposed thereto, nor do I know whether that of the 
English ur the French is contrary to it.^] 

§ 15. Ph. It is further to be remarked that men learn the 
names before the ideas of the mixed modes ; the name showing 
them that this idea deserves to be observed. 

Th. [This remark is a good one, although it is true that 
uow-a-days children, with the aid of nomenclators, ordinarily 
learn the names not only of the modes, but also of substances, 
before the things, and indeed rather the names of substances 
than of the modes 5 for it is a defect in these same nomen- 
clators that they employ nouns only, and not verbs ; not con- 
sidering that verbs, although signifying the modes, are more 
essential in conversation than the majority of nouns, which 
indicate particular substances.-] 



CHAPTER VI 

OF THE NAMES OF SUBSTANCES 

§ 1. Ph. The genera and species of substances, as of other 
beings, are only sorts. For example, suns are a sort of stars, 
i.e. they are fixed stars, for it is not Avithout reason that we 
think each fixed star would make itself known as a sun to 
a person jilaced at a proper distance. § 2. Xow that which 
limits each sort is its essence. It is known either by its 
interior structure, or by external indications which make us 
recognize it and call it by a certain name : and thus it is that 
we may recognize the clock of Strasburg either as the clock- 
maker who made it, or as a spectator who sees its effects. 

Til. [If this is your statement, I have nothing to oppose 
to it.] 

1 Cf. New Essays, Bk. II., chap. 22, § 2, Th. ante, p. 222; Discours de Meta- 
physiqne, 1G86, § 29, Gerhardt, 4, 4.52. For the meaniu^ and use of these terms : 
in Latin, idea, notio, conceptus or conceptio ; in French, idee, notion, concep- 
tion; in German, Idee, Vorstelhinr/, Berjrif; in English, idea, notion, con- 
ception or concept, which varies according to the period in the history of 
thought in which thej' are employed, and according to the theory of knowledge 
implicitly or consciously held by the author using them, cf. Kra'uth-Flemming, 
Vorab. of the Philos. Sciences, ed. of 1877, sub voc. — Tr. 

2 " For," as Schaarschmidt says, " the activity is first perceived, and by its 
means the substance recognized and formulated." — Tk. 



en. vij ON HUMAN UNDERSTANDING 331 

Ph. I express myself in a way suited not at all to renew 
our discussions. But I add that the essence is related only 
to sorts, and that nothing is essential to individuals. An 
accident or a disease may change my color or shape ; a fever 
or a fall may take away my reason or memory; apoplexy 
may leave me neither feeling, understanding, nor life. If 
you ask me if it is essential to me to have reason, I reply : 
no. 

Th. [I think that there is something essential to individuals 
and more than you suppose. It is essential to substances to 
act, to created substances to suffer, to minds to think, to bodies 
to have extension and motion. That is, there are some sorts 
or species to which an individual cannot (naturally at least) 
cease to belong, when it has once been of their number, what- 
ever revolutions may happen in nature. But there are some 
sorts or species, which are accidental (I admit) to the indi- 
viduals, which may cease to belong to them. Thus you 
may cease to be healthy, beautiful, wise, and indeed to be 
visible and palpable, but you cannot cease to have life and 
organs and perception. I have stated sufficiently, above, why 
it appears to men that life and thought sometimes cease, 
although they cease not to endure and to have their effects.] 

§ 8. Ph. Many individuals ranked under a common name, 
considered as belonging to one species only, have nevertheless 
very different qualities depending upon their real (particular) 
constitutions. This is easily observed by all those who ex- 
amine natural bodies ; and chemists often are convinced of it 
by sad experience, when they vainly seek in one portion of 
antimony, sulphur, and vitriol for the qualities which they 
have found in other portions of these minerals. 

Th. [No statement has more truth, and I could myself even 
furnish intelligence concerning it. Books have also been written 
expressly de infido experimentorum chymicorum successu. But 
the error consists in taking these bodies as similar or uniform, 
while they are more mixed than we suppose ; for in dissimilar 
bodies we are not surprised to remark differences between 
individuals, and physicians do not know how much the tem- 
peraments and natural dispositions of human bodies differ. 
In a word, we shall never find the final logical species, as I 
have already remarked above, and two real or complete indi- 



;5;]2 T.EIHNITZ'S CRITIQUE OF LOCKE [hk. hi 

vidnals of one and the same species are never perfectly 
alike.'] 

Ph. We do not notice all these differences, because we do 
not know the little parts, nor consequently the interior struct- 
ure of things. Thus we do not avail ourselves of them in 
order to determine the sorts or species of things, and if we 
wished to do so by means of these essences, or by Avliat the 
schools call substantial forms, we should be like a blind man 
Avho desired to arrange bodies according to colors. § 11. AVe 
do not indeed know the essences of spirits, we know not how 
to form distinct specific ideas of angels, although we well 
know that there must be many kinds of spirits. Thus it 
seems that in our ideas we put no difference between God and 
the spirits by any number of simple ideas, save that we attribute 
infinity to God. 

Th. [There is, however, another difference in my system 
between God and created spirits, viz. that in my view all 
created spirits must have bodies, just as our soul has one.^] 

§ 12. Ph. I think at least that there is this analogy between 
bodies and spirits, that as there is no gap in the varieties of 
the corporeal world, so there will be no less variety in intelli- 
gent creatures. Commencing from ourselves and proceeding 
even to the lowest things, a descent is made by very small 

1 Cf. New Essays, Preface, ante, p. 51, Bk. II., chap. 27, ante, p. 238 sq. ; 
De ipsa natnra, § 13, Gerhardt, 4, 512, Erdmann, 158, b, Jacques, 1, 4()4 (in 
French), trans. Duncan, Philos. Works of Leibnitz, 122,123; Monadoloqie, § 9, 
G. 6, 608, E. 705, J. 2, 31)2, trans. D. 219, "f. H. Hedge, " Jour. Spec. Philos.," 

1, 129 ; 4th letter to Clarke, §§ 4 sq., G. 7, 372, E. 755, b, J. 2, 432, trans. D. 247, 
• 5th letter to Clarke, § 21, G. 7, 393, E. 765, J. 2, 449, trans. D. 258. This is the 

principle of the identity of iudiscernibles, principium identitatis iiidiscerni- 
bilium — i.e. that " things qualitatively undistinguishable are absolutely identi- 
cal." According to Leibnitz, there are no such things, there being in the 
universe no two objects perfectly alike ; though abstractly possible, they are 
inconsistent with the order of things, and with the divine wisdom, which 
admits nothing therein without reason. Cf. also Kant's development and 
criticism of Leibnitz's principles in his Bilucidatio nova, 1755. Werke, ed. 
Rosenkranz & Schubert, Leipzig, 1838-42, Vol. 1, p. 1; ed. Hartenstein, Leipzig, 
1867-68, Vol. 1, p. 365, Erit. d. r. Vernunft, V. d. Amphibolie d. Refteyions- 
beuriffe, ed. R. & S. 2, 214, ed. H. 3, 225, 4th ed., J. H. v. Kirchmann, Leipzig, 
1877, p. 268 sq., E. Caird, The Crit. Philos. of Immanuel Kant, 1, 106 sq., 445 
sq., .500 sq.. New York, Macmillan & Co., 1889; Ueberweg, Hi.<it. of Philos., 

2, 144, 173, Ueberweg-Heiuze, Gesch. d. Philos., 7th ed., 3, 215, 259. —Tr. 

■■2 Cf. Nev; Essays, Preface, ante, p. 52, Bk. II., chap. 1, § 12, Th. ante, p. 113, 
chap. 15, § 4, Th. ante, p. 159, and note. — Tr. 



cii. VI] ON HUMAN UNDERSTANDING 333 

degrees, and by a continued series of things, wldeli in each 
remove differ very little one from the other. There are fishes 
that have wings, and to Avhom the air is not strange, and there 
are birds inhabiting the water whose blood is cold like that of 
the fishes, and whose flesh so strongly resembles theirs in 
taste that the scrupulous are allowed to eat them on fish- 
days. There are animals so closely approaching the species 
of birds and of beasts that they hold the middle ground between 
them. The amphibia contain both terrestrial and aquatic ani- 
mals. Seals live upon the land and in the sea; and porpoises 
(whose name signifies sea-hog) have the warm blood and the 
entrails of a hog. ISTot to speak of that which is reported of 
sea-men,^ there are some animals who seem to have as much 
knowledge and reason as some that are called men ; and there 
is so close a relation between animals and vegetables, that 
if you take the most imperfect of the one and the most perfect 
of the other, you will scarcely perceive any considerable dif- 
ference between them. Thus, until we reach the lowest and 
least organized parts of matter, we shall find everywhere species 
bound together, and differing only by degrees almost impercept- 
ible. And when we consider the wisdom and infinite power of 
the Author of all things, we have reason to think that it is con- 
formed to the magnificent harmony of the universe and to the 
great design as well as to the infinite goodness of this sovereign 
architect, that the different species of creatures ascend, also, 
little by little from us towards his infinite perfection. Thus 
we have reason to be persuaded that there are many more 
species of creatures above us than below us, because we are 
much more distant in degrees of perfection from the infinite 
being of God than from that which approaches nearest to 
nothing. Yet we have no clear and distinct idea of all these 
different species. 

Th. [I had intended in another place to say something not 
ruilike what you, sir, have just set forth ; but I am glad to 
liave been anticipated when I see that you state things better 
than I could hope to have done. Clever philosophers ^ have 

1 I.e. mermaids; so Locke, "mermaids or sea-men," Philos. Works, Vol. 2, 
p. 49 (Bohu'sed.). — Tr. 

2 C'f. Theodicee, Pt. I., § 14, Gerhardt, 6, 110, Erdmaun, 507, b, Jacques, 
2, 80, Dutens, 1, 131 (in Latin) ; Reply to Bayle, ad fin., G. 4, 570, E. I'JO, b. 



334 LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 

discussed this question : utrum detur vacuum formarum, I.e. 
whether there are possible species, which, however, do not 
sexist, and' which nature may seem to have forgotten. I have 
reason to believe that all possible species are not compossible 
in the universe, great as it is, and that, too, not only in rela- 
tion to things which exist contemporaneously, but also in 
relation to the whole series of things. That is to sa}^, I believe 
that there are of necessity species which have never existed 
and never will exist, not being compatible with this series of 
creatures which God has chosen. But I believe that all things, 
Avhich the perfect harmony of the universe can receive, exist 
therein. That there may be intermediate creatures between 
those which are far apart is in conformity with this same 
harmony, although this is not always in one and the same 
globe or system, and that which is between two species is 
sometimes so in relation to certain circumstances and not in 
/'^relation to others. Birds, so different from man in other 
1 things, approach him in speech ; but if monkeys could speak 
^v^like parrots, they ^vould go farther. The laic of continuity ^ 
declares that nature leaves no gap in the order she follows ; 
but every form or species is not the whole order. As for 
spirits or genii, as I hold that all created intelligences have 
organized bodies, whose perfection corresponds to that of the 
intelligence, or the mind, which is in this body in virtue of 
the pre-established harmony, I hold that in order to gain any 
conception of the perfections of spirits above us, it will be of 
great service to imagine these perfections also in bodily organs 
which surpass our own. It is a case in which the liveliest 

D. 2, 93: "n sepeut cependant, que ce Chevalier ait encor eu quelque bon eu- 
thousiasme, qui I'ait transporte dans ce monde invisible, et dans cette etendiie 
infinie, doiit il parle, et qv\e je crois estre celle des ide'es on des formes, dont out 
parle encor quelques Scholastiques en mettant en question, utrum detur 
vacuum formarum.'' — Tr. 

1 Cf. New Essays, Preface, ante, p. 50, Bk. IV., chap. 16, § 12, Th., infra, 
p. 552; Theodic^e, III., § 348, Gerhardt, G, 321, Erdmann, 605, b, Jacques, 2, 
270; Letter to Bayle, in the " Nouvelles de la Ke'publique des Lettres," July, 
1(187, G. 3, 52, E. 104, traus. Duncan, Philos. Works of Leibnitz, 33; Letter to 
Aruauld, 1690, G. 2, 136, E. 107, b, J. 1, 444, trans. D. 38. Animadversioiies in 
partem generulem Principiorum Cartesianorum, Pt. IL, ad Art. 45, G. 4, 375, 
Duncan, 61 ; Guhrauer, G. W. Freiherr v. Leibniz, eine Bioyraphie, 1, 264, 
and notes, pp. 31-33, a letter to an unknown person, Oct. 16, 1707, containing 
a very clear statement of the principle or law of continuity; translation, 
Appendix, pp. 712-714. — Tk. 



CH. VI] ON HUMAN UNDERSTANDING 335 

and richest imagination, and, to avail myself of an Italian 
term which I cannot well express otherwise, the invenzione la 
2:>iu vaga, will be most timely in raising us above ourselves. 
And what I have said in justification of my system of harmony, 
which exalts the divine perfections beyond what we had dared 
to think, will assist us also in having ideas of creatures in- 
comparably grander than we have had hitherto. 

§ 14.^ Ph. To return for a little to the reality of species 
even in substances, I ask you if water and ice are different 
species ? 

Th. [I, in my turn, ask you if gold melted in the crucible 
and gold cooled in bullion are of one and the same species ?] 

Ph. He does not reply to the question, who proposes an- 
other, 

Qui litem lite resolvit.^ 

But you thereby admit that the reduction of things to species 
relates solely to the ideas we have of them, which suffice to 
distinguish them b}^ names ; but if we suppose that this dis- 
tinction is founded upon their real and internal constitution, 
and that nature distinguishes existing things into so many 
species by their real essences, in the same manner as we 
ourselves distinguish them into species by these or those 
names, we shall be liable to great mistakes. 

Th. There is some ambiguity in the term species, or a being 
of a different species, which causes all this confusion ; and 
when we have removed it, there will no longer be discussion 
save perhaps as regards the name. We may take species 
mathematically and physically. In mathematical strictness 
the least difference making two things in any respect dissimilar, 
makes them different in species. Thus, in geometry, all circles 
are of one and the same species, for they are all perfectly alike, 
and for the same reason all parabolas are also of the same 
species ; but it is not the same with ellipses and hyperbolas, for 
of these there is an infinite number of sorts or species, as 
well as an infinite number of each species. All tlie numberless 

1 Locke has § 13, Philos. Wo7-Jcs, Vol. 2, p. 60. The numbering § 14 in the 
French text of all the editions is an error, as will he seen upon comparing 
tlie numbering of the next §, also 14, with Locke's text. Here also the texts 
coincide with Locke's. — Tr. 

- Cf. Horace, Satires, 2, 3, 10.'}. — Tr. 



3:]G LE1B2\ITZ'S ClUTIQUE OF LOCKE [bk. in 

ellipses, in Avhicli the distance of the foci has the same ratio to 
the distance of the apices, are of one and the same species ; bit* 
as the ratios of these distances vary only in size, it follows that 
all these infinite species of ellipses make only one genus, and that 
there are no subdivisions. On the other hand, an oval of three 
foci would have indeed an infinite number of such genera, and 
would have an infinitely infinite number of sjyecies, each genus 
having a number of them simply infinite. In this sense two 
physical individuals will never be perfectly similar, and what is 
more, the same individual will pass from species to species, for it 
is never wholly similar to itself even for more than a moment. 
But the men who establish physical species do not adhere to 
this strictness, and it depends upon them to say that a mass 
which the}^ can make return to themselves under its first form 
continues to be one and the same species in their view. Thus 
we say that water, gold, quicksilver, common salt, continue 
the same, and are only disguised in ordinary changes ; but 
in organized bodies, or in species of plants and of animals, we 
define species by generation, so that this similarity, which 
comes or may have come from one and the same origin or 
seed, would be of one and the same species.^ In man, besides 
human generation, we fasten upon the attribute rational animal ; 
and, although there are men who live like beasts all their 
lives, we presume that it is not for want of faculty or principle, 
but that it is through impediments which stand in the way 
of this faculty. But it is not yet determined as regards all 
the external conditions which we wish to regard as sufficient 
to give this presumption. But whatever regulations men 
make for their denominations and for the rights attached to 
names, provided that their regulation is followed or made fast 
and intelligible, it will be founded in reality, and they will 
not be able to imagine species which nature, which includes 
even possibilities, has not produced or distinguished before 
them. As for the interior, although there is no external ap- 
pearance which is not based upon the internal constitution, it 
is nevertheless true that one and the same appearance may 
sometimes result from two different constitutions. But in 



1 Cf. New Essays, Bk. III., chap. 3, § 14, Th. (2), ante, p. 314; Dewey, Leib- 
niz's New Essays, p. 215 sq. — Tr. 



CH. VI] ON HUMAN UNDERSTANDING 337 

that case there will be something in common, and this is what 
we philosophers call the proximate formal cause. But although 
this should not be, as if according to Mariotte ^ the blue of 
the rainbow had an entirely different origin from the blue 
of the turquoise, unless there were a common formal cause (in 
which opinion I do not at all agree with him), and although 
we should agree that certain apparent natures which make us 
give names have nothing internal in common, our definitions 
would not cease to be grounded in real species ; for the 
phenomena themselves are realities. We can say, then, that 
all which we truthfully distinguish or compare, nature dis- 
tinguishes or makes agree also, although she has distinctions 
and comparisons which we do not know and which may per- 
haps be better than ours. Thus much care and experience is 
yet necessary in order to assign genera and species in a manner 
sufficiently like nature. Modern botanists think that the dis- 
tinctions taken from the forms of flowers most resemble the 
natural order." But they find therein, however, still much 
difficulty, and it would be advantageous to make comparisons 
and arrangements not only upon a single character, like that 
of which I have just spoken, which is taken from flowers, 
and is perhaps the most suitable up to this time for a possible 
system and conveident for learners, but also upon characters 
taken from other parts and relationships of plants : each 
basis of comparison deserving tables of its own ; ^ without 
which we shall allow many subaltern genera, and many com- 
parisons, distinctions, and useful observations to escape. But 
the more thoroughly we examine the generation of species, 
and the more we follow in the classifications the conditions 
which are there requisite, the closer we shall approach the 
natural order. Therefore, if the conjecture of some intelligent 
persons were found true, that there is in the plant besides the 

1 Cf. ante, p. 121, note 4. — Tr. 

2 Cf. Dutens, Leibnit. opera omnia, Vol. 2, Pt. II., p. 1G9 sq., Epistoln G. G. 
Leibnitii ad A. C. Gackenholtzium, M. D. De Methodo liotaru'ca, April 23, 
1701. — Tr. 

3 Of. Mor. Willi. Di-obisch, Neuc Darstg. d. Lor/ik, .3d ed., Leipzi.-?, 1803, 
p. 141 .sr/., where tlie so-called Collateral Distributions or Go-divisious, which 
Leibnitz here calls to mind, and " which are of especial importance in Statis- 
tics," are discussed. Drobisch's woi'k is considered " one of the most jierfect 
presentations ol the subject-matter from the point of view o£ formal logic." 
— Tr. 



&J8 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

seed {la graine) or the recognized seed (la semence) correspond- 
ing to the egg of the animal, another seed which would deserve 
the name masculine, i.e. a powder {pollen, visible very often, 
though sometimes, perhaps, invisible, as the seed (la graine) 
itself is in certain plants) which the wind or other ordinary- 
accidents scatter in order to unite it with the seed which comes 
sometimes from one and the same plant, and sometimes, also 
(as in the hemp), from another neighboring plant of the same 
species, which plant consequently will be analogous to the 
male, though perhaps the female is never wholh' destitute of 
this same pollen; if this conjecture, I say, were found true, 
and if the mode of generation of plants became better known, 
I do not doubt that the varieties which would be noticed would 
furnish a basis for very natural divisions. And if we had the 
penetration of some superior geniuses and knew enough about 
things, perhaps we should find therein fixed attributes for 
each species, commou to all the individuals and always sub- 
sisting in the same living organism, whatever alterations or 
transformations may happen to it, as in the best known of the 
physical species, the human, reason is such a fixed attribute, 
granted to each individual, and never to be lost, although 
it cannot always be perceived. But in default of this knowl- 
edge we avail ourselves of the attributes which appear to us 
most convenient for distinguishing and comparing things, and 
in a word, for recognizing in them species or sorts ; and these 
attributes have always their real grounds.] 

§ 14. Ph. In order to distinguish substantial beings accord- 
ing to the usual supposition, that there are certain essences or 
precise forms of things, whereby all existing individuals are 
naturally distinguished into species, it would be necessary to 
be assured, § 15. first, that nature always proposes, in the 
production of things, to make them participate in certain 
regular and established essences, as models ; and, § 16. sec- 
ondly, that nature always attains this end. But monsters 
give us reason to doubt both. § 17. It would be necessary 
to determine, in tlie tliird pjlace, whether these monsters are 
really a distinct and new species, for we find that some of 
these monsters have few or none of those qualities which are 
supposed to result from the essence of that species whence 
they derive their origin, and to which they seem to belong in 
virtue of theii- birth. 



CH. VI] ON HUMAN UNDERSTANDING 339 

Th. When it is a question of determining wliether monsters 
belong to a certain species, we are often reduced to conjecture. 
This shows us that we are not, then, limited to external con- 
siderations, since we should divine whether the internal nature 
(as, for example, reason in man) common to the iijdividuals of 
such a species, still suits (as birth makes us conjecture) these 
individuals, in Avhoni a portion of the external characteristics, 
ordinarily found in this species, is lacking. But our incerti- 
tude nowise affects the nature of things, and if there is such 
a common internal nature, it will or will not be found in 
the monster, whether we know it or not. And if the internal 
nature of any species is not found therein, the monster will be 
of its own species. But if there were no such internal nature 
in the species under discussion, and if the question was not 
decided by birth either, then the external marks alone would 
determine the species, and monsters would not belong to that 
species from which they deviate, unless taken in a manner a 
little vague and with some latitude ; and in this case, also, 
our trouble in desiring to divine the species would be in vain. 
This is perhaps what you mean by all the objections you make 
to species taken as real internal essences. You ought then to 
prove, sir, that no common internal specific mark exists, since 
the external is wholly missing. But the contrary is found in 
the human species in which sometimes children who have 
some monstrosity reach an age in which they exhibit reason. 
Why, then, could there not be something similar in other 
species ? It is true that for want of knowledge of them we 
cannot avail ourselves of it to define them, but the exterior 
takes its place, although we recognize the fact that it is insuffi- 
cient for an exact definition, and that the nominal definitions 
themselves in these instances are only conjectural ; and I 
have already stated above how sometimes they are only pro- 
visioned. For example, w^e might find a way to counterfeit 
gold so that it might satisfy all the tests which we have up to 
the present time ; but we might also then discover a new method 
of testing which would give the means of distinguishing natural 
gold from this tvhich is artificially made. The old joui'uals at- 
tribute both (discoveries) to Augustus, Elector of Saxony ; ^ 

1 Augustus I., tlic lirotlier of Mauriro, was Elector 155.3-1580, and, according to 
Soliaaj'schuiidt, " shared with his wile, Auua of Denmark, the love for alchemy." 
— Tk. 



340 LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 

but I am not the man to guarantee tins fact. But if it 
were true, we could have a more j)^i'f^ct definition of gold 
than we have at present, and if artificial gold could be made 
in quantity and cheap, as the alchemists claim, this new proof 
would be important ; for by its means we could preserve for 
the human race the advantage which natural gold gives us in 
commerce by its rarity, while furnishing ourselves with a 
substance which is durable, uniform, easy to divide and to 
recognize, and precious in small volume. I wish to avail 
myself of this occasion to remove a difficulty (see § 50 of the 
chapter, " On the iSTames of Substances," in the author of 
the Essay on Understanding). The objection is made that in 
saying : All gold is fixed, if we understand by the idea of gold 
the mass of certain qualities in which fixedness is comprised, 
we make only an identical and useless proposition, as if we 
said : Fixedness is fixedness ; but if we understand thereby a 
substance given a certain internal essence, of Avhich fixedness 
is a result, we shall not speak intelligiblj", for this real essence 
is wholly unknown. I reply that the body given this internal 
constitution is designated by other external marks in which 
fixedness is not comprised, as if any one said : the heaviest 
of all bodies is also one of the most fixed. But all that is 
only provisional, for we might some day find a volatile body, 
as a new mercury, which would be heavier than gold, and upon 
which gold would float, as lead floats upon our mercury. 

§ 19. Ph. It is true that in this way we can never know 
precisely the number of properties depending on the real 
essence of gold unless we know the essence of gold itself. 
§ 21. [But if we limit ourselves precisely to certain properties, 
that will be sufficient to enable us to have exact nominal 
definitions which will serve us for the present, reserving to 
ourselves the privilege of changing the signification of names, 
if any new useful distinction is discovered.] But it is neces- 
sary at least that this definition correspond to the use of the 
name, and be capable of being put in its place. This serves 
to refute those who maintain that extension constitutes the 
essence of body, for when it is said that one body gives an 
impulse to another, the absurdity would be manifest, if substi- 
tuting extension (for body) we should say that one extension 
puts in motion another extension by means of an impulse, for 



CH. vi] ON HUMAN UNDERSTANDING 341 

in aclclitiou solidity is necessary. In like manner no one will 
say that reason, or that which makes man rational, makes 
conversation ; for reason does not constitute the entire essence 
of man ; there are rational animals who converse with each 
other. 

Th. I think you are right : for the objects of abstract and 
incomplete ideas are not sufficient to give the subjects of all 
the actions of things. But I think that conversation agrees 
with all minds who can interchange their thoughts. The 
scholastics are greatly troubled regarding the angelic method 
of communication ; but if they would accord the angels subtile 
bodies, as I do, following the ancients, they would experience 
no further difficulty in that regard.^ 

§ 22. Ph. There are some creatures in the world which 
have forms similar to ours, but are hairy and use neither 
language nor reason. There are imbeciles ^ among us who 
have exactly the same form as ourselves, but who are destitute 
of reason, and some of them make no use of language. There 
are some creatures, as it is said, which, with the use of lan- 
guage and of reason and a form similar in every other respect 
to ours, have hairy tails ; at least, it is not impossible that 
there are such creatures.^ There are others, where the males 
have no beard, and others, where the females have. If you 
ask whether all these creatures are men or not, whether they 

1 Cf. New Essays, Preface, ante, p. 52, Bk. III., chap. R, ante, p. .332, note 
2 ; also letters to Des Bosses, Sept. 20, Oct. 4, 1706, Gerhardt, 2, 310, 319, 
Erdmann, 439, 440. —Tr. 

^Loekelias: " naturals," P7»7o.s. ^Fo?•^•,s, Vol. 2, p.53(Bohn's ed.). — Tr. 

3 The myth of men with tails, here mentioned and accepted as credible by 
Locke, arose either from the superficial observation of African travellers, or 
from their uncritical acceptance and rehearsal of the stories of such Negroes 
as claimed to have seen such beings, assumed by them to be endowed with 
reason, although covered with hair and furnished with tails — stories which 
seem to rest upon a confusion of men with man-like apes, a confusion the 
more naturally suggested as many tribes of negroes regard the apes as rational 
but uncivilized human beings. The myth has been exploded in our day by the 
knowledge furnished by scientific explorers into the interior of Africa (the 
assumed abode of the.se beings), such as Dr. Georg August Schweinfnrth, who 
states that among the tribes of Central Africa the Dyoor, the Niam-niam, and 
the Bongo, Insten upon themselves behind, as a part of their dr(!ss, the tails 
of animals, as, for example, that of "the quercza monkey (Colohns)," or tails 
"composed of the bast of the Sanseviera." Of. bis Jm Ilerzrn ron Afrika, 
English trans, by Ellen E. Fr(>wer, 2 vols.. New York: Harper & Bros., 1874, 
Vol. 1, pp. 201, 294-0, Vol. 2, pp. 2, 0, 11, 137. —Tr. 



342 LEIBNITZ'S CRITIQUE OF LOCKE [ijk. iu 

belong to the human species, it is plain that the question 
rt'i'ors only to the nominal delinition, or to the complex idea 
wi" have made for ourselves in order to indicate it by this 
name ; for the internal essence is absolutely unknown to us, 
although we have reason to think that where the faculties, or 
rather the external hgure, are so different, the internal consti- 
tution is not the same. 

Th. I think we have in the case of man a definition at once 
real and nominal. For nothing can be more internal to man 
than reason, and ordinarily it makes itself well known. There- 
fore the beard and the tail will not be considered in comparison 
with it. A man of the forest, though hairy, will make himself 
recognized : and it is not the hair of a magot ^ which excludes 
him. Imbeciles lack the use of reason; but as we know by 
experience that reason is often bound and cannot appear, and 
as this happens in the case of men who have exhibited and 
will exhibit reason, we make, probably, the same judgment 
regarding these imbeciles upon other indications, i.e. upon 
their bodily figure. It is only by these signs, united with 
their birth, that we presume that infants are men, and will 
manifest reason ; and we are seldom deceived. But if there 
were rational animals with an external form a little different 
from ours, we should be embarrassed. This shows that our 
definitions, when dependent upon the exterior of bodies, are 
imperfect and provisional. If any one called himself an 
angel, and knew, or knew how to do, things much above us, he 
might be believed. If some one else, like Gonzales,^ came 
from the moon l)y means of some extraordinary machine, and 
told us credible things about his native country, he would pass 

1 The Barbary ape. — Tr. 

2 Cf. L'llomme. davs la Inne, ou le voyage chim^riqiie fait au monde de la 
lune, nouvellement de'couvert par Dominiqxie Gonzales, avanturier Espar/nol, 
atitrernent dit le courier volant, mis en nostre lanque par J. B. D. (Jean Bau- 
doiii), Paris, 1648, 8vo, pp. 176; reprinted Paris, 16C(), with illustrations, and 
also Paris, 1731, 12mo. Brunet states that this is the French translation of 
Franc. Godwin, 7Vie 3fan in the Moon, or a discourse of a voyage thither by 
Domingo Consoles, London, 1638, also 1657, etc., 12mo; that it had some suc- 
cess, and that it is supposed that Swift borrowed some passages from it for his 
Gulliver's Travels. Cf. E. A. Poe, Works, New York, 1867,Vol. 1, p. 49, who 
gives, in a note at the end of the story of " The unparalleled adventure of one 
Hans Pfaall," the full title of the French book, together with some account of 
its contents, including the machine of Gonzales. — Tk. 



CH. vi] ON HUMAN UNDERSTANDING 343 

as a lunar being, and yet we miglit accord him indigineity and 
the rights of citizenship, with tlie title of man, entire stranger as 
he would be to our globe ; but if he asked for baptism and 
wished to be received as a proselyte of our law, I think that 
we should see great discussions arise among the theologians. 
And if communication were opened with these planetary men, 
sufficiently approaching ourselves according to Huygens,^ the 
question would require a universal council in order to know 
whether we ought to extend the care of the propagation of the 
faith even beyond our globe. Many would doubtless maintain 
that the rational animals of these countries, not being of the 
race of Adam, have no part in the redemption of Jesus Christ ; 
but others would perhaps say that we have not sufficient 
knowledge either of the place where Adam has always been, 
or of what has been done with all his posterity, since there 
have been theologians, indeed, who believed that the moon 
was the place of paradise ; and perhaps that with the plurality 
we should conclude for the surest thing, viz., to baptize these 
men upon condition that they be susceptible of baptism; but 
I doubt whether we should ever wish to make them priests 
in the Roman Church, because their consecration would always 
be doubtful, and we should expose the people to the danger 
of a material idolatry, according to the hypothesis of this 
church. Happily the nature of things exempts us from all 
these embarrassments ; but these bizarre fictions are useful in 
speculation, in order rightly to know the nature of our ideas. 

§ 23. Ph. Not only in theological questions, but also on 
other occasions some would perhaps wish to regulate them- 
selves by the race, and to say that in animals propagation by 
the copulation of the male and the female, and in plants by 
means of the seeds, keeps the supposed real species distinct and 
entire. But this would serve only to fix the species of animals 
and vegetables. What must be done about the rest ? And 
even as regards these it is not sufficient, for if history is to be 
believed, women have been gotten with children by magots. 
And here is a new question : Of what S])ecios must sueli a 
pr()(Uiction be ? You often see mules and jiini;u'ts (sec Dietioii- 

1 Cf. nntp, p. 1.50, iHito :'.. Lclhnizoia it. Iltii/i/hcn's Rriefwcchseln, v. E. 
Gerlund, Berlin, issl.— Tii 



344 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

iiaire fitymologique de M. IMenage '), the first begotten bjj^ an 
ass and a luave, tlie last by a bull and a mare. I liave seen an 
animal begotten of a cat and a rat, wliicli had visible marks of 
these two animals.^ Whoever will add thereto the monstrous 
productions, will find that it is very hard to determine species 
by generation ; and if it can only be done by that means, must 
I go to the Indies to see the father and mother of a tiger, and 
the seed of the tea-plant, and could I not otherwise decide 
whether the individuals which come to us are of these species ? 
Til. Generation or race gives at least a strong presumption 
(i. e. a provisional proof) and I have already said that very 
often our signs are only conjectural. The race has sometimes 
been contradicted by the figure, as when the child is unlike 
the father and mother, and the mixture of figures is not 
always the sign of the mixture of races ; for it may happen 
that a female gives birth to an animal which seems to belong 
to another species and that the mother's imagination alone 
has caused this irregularity : to say nothing of what is called 
mola.^ But as meanwhile we judge provisionally the species 
by the race, we also judge the race by the species. For when 
a forest child,'* taken from among the bears, who had many of 
their ways, but who made himself known at last as a rational 
animal, was presented to John Casimir,^ king of Poland, he 
did not scruple to believe him of the race of Adam, and to 
baptize him under the name of Joseph, although perhaps upon 
the condition, si haptizatus non es, according to the usage of 
the Roman church, because he might have been carried off by 
a bear after baptism. We have not as yet sufficient knowledge 

1 Cf. Dutens, Leibnit. op. 07n., 5, 350, 543; 6, Pt. II., 21, Gerhardt, 2, 5.30, 
539. Grilles Menage, 1613-1692. The first ed. was entitled Origines de la langue 
fran<;oise, Paris, 1650, 4to. A new ed. appeared at Paris, 1694, fol., under the 
name, Bictionnaire Etymologique de la lanrjue frawpise, etc.; and this was 
afterwards enlarged and edited by A. F. Janlt, Paris, 1750, 2 vols., fol. — Tr. 

2 An instance of superficial observation and hasty inference, like that of 
the men with tails above mentioned, ante, p. 341, note 3. — Tr. 

3 An amorphous fleshy mass in the uterus. — Tr. 

* Schaarschmidt states that J. H. F. Ulrich, in his German trans., with ad- 
ditions and notes, Halle, 1778-80, of Raspe's (Eurres ijhilosoph. latines etfran- 
<;aises defeu Mr. Leibniz, "gives in a note, p. 1-39-140, information concerning 
the child of the bears found in the forest, without, however, quoting the source 
of his communications." — Tr. 

5 John II., Casimir V., 1609-1672. He was elected king of Poland in 1614, 
and abdicated in 1088. — Tr. 



CH. VI] ON HUMAN UNDERSTANDING 345 



of the effects of the intermixture of animals : and often mon- 
sters are destroyed, instead of being brought up, whilst they 
are seldom long lived. The belief is that mixed animals do 
not multiply ; but Strabo ^ attributes propagation to the mules 
of Cappadocia, and letters from China tell me that in neigh- 
boring Tartary there are race-mules. We see also that the 
mixtures of plants are capable of preserving their new spe- 
cies.^ We do not always indeed know in the case of animals 
whether it is the male or the female, or both, or neither, 
which determines the species. The doctrine concerning the 
eggs of females which the late Mr. Kerkring^ made famous, 
seemed to reduce the males to the condition of moist air as 
related to plants, Avhich furnishes seeds with the means of 
pushing and raising themselves from the earth ; following the 
verses of Vergil which the Priscillianists * were wont to repeat ; 

1 Cf. Geographica, p. 212, ed. Casaubon, 1G20; Bk. V., chap. 1, § 4, ed. by 
Gustav Kramer, Berlin, 1844-52, 3 vols., 8vo; English trans. Vol. 1, p. 31(5 
(Bohu's Class. Lib.), London, 1887. — Tr. 

2 Cf. C. Darwin, 1S09-1882, Origin of Species, and the new inquiries and 
investigations consequent upon it. — Tr. 

3 Theodore Kerkkrinck, it!40-l()93, a Dutch physician, born at Amsterdam, 
died at Hamburg, a fellow-puiMl with Spinoza, 1G32-1677, of a physician, 
Francis Van <ler Ende, and author of works on medicine, anatomy, and chem- 
istry, among which was the one here referred to by Leibnitz : Anthropogeniss 
ichnographia sive conformatio foetus ab ovo usque ad ossificationis principia, 
in supplementum osteogenic fwtuum, 4to, Amstelodami, 1671. His Opera 
omnia anatomica, 2d ed., 4to, Lugd. Bat., 1717. Cf. Dutens, Leibnit. op. om., 
5, 173, 199; F. Pollock, Spinoza: His Life and Philosophij, p. 13. — Tr. 

4 The Priscillianists were an heretical sect which appeared in Spain toward 
the close of the fourth century, and continued till about the middle of the 
sixth. Their speculative doctrines are a combination of Christianity with 
Gnosticism and Manichfeism. Their moral system was rigidly ascetic, and 
celibacy was required. The charges of immorality and licentiousness so fre- 
quently brought against them by their adversaries, " are, to say the least, not 
sufficiently well authenticated." The information that they made use of these 
verses of Vergil, to which they attached a religious dogma, as a foundation 
for their heresy and alleged sexual license comes from a letter of Jerome, 
c. 34f;-420, to Ctesiphon, Epist. 133 ad Ctesiphontem, Opera, ed. Vallarsi, 
Veronffi, 1734-42, Vol. 1, p. 1029, a; 2d ed., Venetiis, 17t)()-72 ; J. P. Migne, 
Patrol, s. Lat., Vol. 22, p. 1150-51, Paris, 1845, latest ed., Paris, 18(54-66. Cf. 
also Sulpicius Severus, 363-406, or 410, IJistor. Sacra, or Chronica, Bk. II., 
chaps. 46-51, and Dialog., III., 11-13, ed. C. Halm, Vienna, 1866 (Vol. 1 of the 
Corpus Script. Eccles. Latinorum), and J. Bernays, Die Chronik des Sulp. 
Severus, Berlin, 1861; A. Neander, Hist, of the Christ. Relig. and Church, 2, 
771-779, Boston, Houghton, Mifflin & Co.; Gibbon, Decline and Fall, MUmnn's 
ed., chap. 27 ; Smith and Wace, Diet, of Christ. Biog., 4, 470-478, London, John 
Murray, 1887. — Tr. 



346 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

Cum pater omiiipotens fcEcundis imbribus aether 
Conjugis ill hftai frrciniiiii) descendit et omnes 
Magnus alit maguo commistus corpore foetus.^ 

In a word according to this hypothesis the male would no 
longer be more than the rain. But Leeuwenhoek^ has reha- 
bilitated the masculine genus, and the other sex is in its turn 
degraded, as if it performed only the earth's function as 
regards seeds, by furnishing them place and nourishment; a 
view which might obtain even if we still maintained the 
theory of the eggs. But this does not prevent the imagination 
of the female from having a great influence iipon the form 
of the fcEtus, even if we supposed that the animal has already 
come from the male. For this is a condition destined ordi- 
narily to a great change, and much more susceptible also to 
extraordinary changes. It is asserted that the imagination of 
a woman in this condition, who was shocked by the sight of a 
cripple, caused the separation of the hand of the foetus very 
near its term, and that this hand was subsequently found in 
the after-birth; a statement, however, which requires confir- 

1 Georrj., 2, 325-327. — Tr. 

2 Antoon van Leeuwenhoek, 1632-1723, a distinguished Dutch naturalist, 
"the father of scieutific microscoi^y," who shares with Malpighi, 1628-1694, 
the discovery of the capillary circulation of the hlood, thus corai^leting the 
doctrine of Harvey, 1598-1657, and with his own pupil, Ludwig Hamm, the 
discovery of the active moving constituents of the seminal duid, which he called 
"animalcula spermatica," or "spermatozoa." Leeuwenhoek communicated 
his discovery, 1677, of the spermatozoa in a letter to Sir Christopher Wren, 
1631-1723, President of the Royal Society, 1681, " De ovario, et imaginovis ejus 
ovis; homo ex animalculo oritur." The letter is found in Leeuwenhoek's 
Arcana naturse detecta sive epistolse ad societatem Regiam Angliam scriptse. 
Delft, 1695, 4to, p. 28 sq. Leeuwenhoek strenuously opi^osed the doctrine of 
".spontaneous generation," and did more than any other naturalist to over- 
throw it. Cf. Dutens, Leihnit. op. om., 5, 173, 174, 319, 337; 6, Pt. I., 211, 213, 
218, Gerhardt, Leibniz, philos. Schrift., 3, 562, 565, 571, 579, 580, Dutens, 2, 
Pt. I., 329, 3.30; Pt. II., 214, Protogsea, § 17; Systhne nouveau, § 6, Ger- 
hardt, 4, 480, Erdmann, 125, b, Jacques, 1, 471, trans. Duncan, Philos. Wks. of 
Leibnitz, 73; Principes de la Nature et de la Grace, § 6, G., 6, 601, E., 715, b, 
trans. D., 212; G., 7, 568. He published the greater part of his discussions and 
investigations in 112 papers in the Philos. Transactions of the Royal Society, 
and in 26 papers in the Memoirs of the Paris Academy of Sciences, of both 
of which bodies he was a member. The most complete collection of his works 
is the Opera omnia sen arcanas natural ope microscopiorum detecta, Leyden, 
1719-22, 4 vols., 4to ; from this. Select Works, trans, by Samuel Hoole, London, 
1800-1807, 2 vols, 4to, does not contain the letter to Wren. There is a Life in 
Dutch by Haaxman, Leyden, 1875. — Tr. 



CH. VI] ON HUMAN UNDERSTANDING 347 

niation. Perhaps some one will arise who will maintain that, 
although the soul can come only from one sex, both sexes 
furnish something of the organism, and that from the two 
bodies one is made, just as we see that the silk-worm is as it 
were a double animal, and encloses a flying insect under the 
form of the caterpillar : in such darkness are we still upon so 
important a point. Some day perhaps the analogy of plants 
will give us some light, but at present we have but little in- 
formation regarding the generation of plants themselves, the 
surmise concerning the pollen which has been remarked, as 
that which might correspond to the masculine semen, not 
yet being very clear. Besides a slip of a plant is very often 
capable of giving a new and complete plant, to which no 
analogy is as yet seen in animals ; also we cannot say that 
the foot of an animal is an animal, as each branch of the tree 
seems to be a plant capable of fruit-bearing by itself. Fur- 
thermore the intermixture of species, and even the changes 
in one and the same species often go on with much success 
in plants. Perhaps at some time or place in the universe 
the si)ecies of animals are, or were, or will be more subject 
to change than they are at present with us, and many animals 
who have somewhat of the cat, as the lion, the tiger, and the 
lynx, might have been of one and the same race and may now 
be as it were new subdivisions of the ancient species of cats. 
Thus I always return to what I have more than once said that 
our determinations of physical species are provisional and 
proportional to our knowledge.^ 

§ 24. Ph. Men at least in making their divisions of species 
have never thought of substantial forms, save those who, in 
this single corner of the world where we are, have learned the 
language of our schools. 

Th. It seems that lately the term substantial forms has 
come into disrepute with certain classes and that they are 
ashamed to speak of them. Meanwhile there is perhaps in 
that circumstance more of fashion than of reason. The scho- 
lastics employed inaptly a general notion, when they used it 
to ex[)lain particular phenomena ; but this abuse does not de- 
stroy the thing. The soul of man is a little disconcerting to 

1 Leibnitz here touclios upon the theory of evolution, or development, but 
keeps himself within very moderate limits in tlie statement of his views. --Tk. 



348 LEIBNITZ'S CRITIQUE OF LOCKE [uk. hi 

the ilnLnnatisin of some of our moderns. There are some who 
admit that it is the form of man; but they also affirm tliat it 
is the only substantial form of known nature. Descartes thus 
speaks of it, and he censures Kegius^ because he contested this 
quality of a substantial form of the soul and denied that man 
was a unum per se, a being endowed with a veritable unity .^ 
Some think that this excellent man did this as a matter of 
policy. I doubt tliis a little because I think he had reason 
for so doing. But this privilege is not given to man only, as if 
nature were made of broken sticks. There is room for the 
judgment that there is an infinite number of souls, or, to speak 
more generally, of primitive entelechies, which have something 
analogous to perception and appetite, and which are all, and 
remain always, substantial forms of bodies. It is true that 
species apparently exist which are not truly a unum per se (i.e. 
bodies endowed with a veritable unity, or with an invisible 
essence wdiich makes their entire active principle), any more 
than a mill or watch might be. The salts, the minerals, and 
the metals may be of this nature, i.e. simple contextures or 
masses in which there is a certain regularity. But the bodies 
of both, i.e. animate bodies as well as the contextures without 
life will be specified by their internal structure, since in those 
indeed which are animate, the soul and the machine,^ each by 



1 Pierre Sylvain Re'gis — Latin, Regius — 1G32-1707, a celebrated Cartesian, 
at first destined for the church, but who, on going to Paris to study tlieology 
at the Sorboune, heard Rohault (cf. ante, p. 233, note 2) on Cartesiauism, 
became a zealous adherent of the doctrine, renounced the priesthood, and gave 
himself up to teaching the new philosophy. His enormous success aroused the 
opposition of Harlay, the Archbishop of Paris, who forbade his teaching. He 
therefore turned to composition, expounding his philosophical ideas in his 
Cours entier cle philosophie, or Systeme general selon les 2^rincipes de Des- 
cartes, 4 vols., 4to, Paris, 1(590, 2d ed., 3 vols., Amsterdam, 1691. He inter- 
preted Descartes in the sense of empiricism, and thus drew upon himself the 
pliilosopher's censure, cf. Descartes, Remarks on the Programme of Regius, 
Works, ed. Cousin, Paris, 1824-2(), Vol. 10, pp. 70-111; see also Veitch,"r/ie 
Method, Meditations and Selections from the Principles of Descartes, 8th ed., 
Edinburgh, 1881, pp. 278, 287. His doctrines were a reaction against the ultra 
idealism of Malebranche. Other works of his are Response it la censura 
philosophise cartesianse, 12mo, Paris, 1691; L'Usaije de la Raison et de la Foi, 
4to, Paris, 1704. — Tr. 

2 Cf. Descartes, 1596-1650, Epist., I., 89, pp. 292-293, ed. of 1668, p. 261, ed. 
of 1692, Cousin's ed.. Vol. 8, pp. 579-583; Gerhardt, Leihniz. philos. Schrift., 
6, 547, 550s(?.— Tr. 

3 I.e. body, according to the linguistic iisage of the Cartesians. — Tr. 



en. VI] ON HUMAN UNDERSTANDING 349 

itself, suffice for the determination ; for they agree perfectly, 
and although having no immediate influence the one upon the 
other, they are mutually expressive, the one having concen- 
trated into a perfect unity all that the other has dispersed in 
the manifold. Thus, when the arrangement of species is the 
question, it is useless to dispute about the substantial forms, 
although it may be well for other reasons to know if there are 
any and what their nature is ; for without this one would be a 
stranger in the intellectual world. For the rest the Greeks 
and the Arabians have spoken of these forms as well as the 
Europeans, and if the common people do not speak of them, 
no more do they speak of algebra or of surds.^ 

§ 25. Ph. Languages were formed before the sciences, and 
ignorant and unlettered people reduced things to certain 
species. 

1 The doctrine of the substantial forms, of which the Mediaeval schoohnen 
made so much use, finds its origin and point of departure in the elSo; and oixrCa 
of Plato and Aristotle. Aristotle used oia-ia in two senses; in its primary and 
proper sit;nification, as a concrete and individual substance, a compound 
(o-ui-oAor) of matter ({lArj) and the determining principle, form (elSos), in which 
sense individual tilings were called "first substances" (npioTai. ovo-i'ai ) ; sec- 
ondly, as applied to the genus, in which sense species were called "second 
substances" (Sevrepoi ouo-i'ai)- According as they Were nominalists or realists, 
tlie Schoolmen, in their interpretation of Aristotle, regarded the substantial 
forms as mere concepts of genus and species, the product of the abstraction- 
power of the mind, which might correspond to, though they did not constitute, 
tlie reality of things ; or, as real universals existing in concrete things, consti- 
tuting their inmost essence and determining its nature. Locke adopts the 
nominalistic view of these forms as purely subjective having no corresponding 
reality in nature. Leibnitz maintains them in the realistic sense as expres- 
sions of the reality of the "first substances," and in direct connection with 
them develops his doctrine of monads. Cf. Discours de Metaphys., 1686, § 10 
sq., Gerhardt, 4, 44.3; Systems nouveau, 1695, §§ 3, 4, 11, G. 4, 478 sq. (also 
ih/>I. first draft, G. 4, 473), Erdmann, 124, Jacques, 1, 470, trans. Duncan, 
Philns. Wl-s. of Leibnitz, 72; De ipsa natura, 1698, §§ 11, 12, G. 4, 510, E. 157, 
J. 1, 462, D. 120; also G. Hartenstein, Uehcr Leibniz's Lehre v. d. VerhUltniss 
d. Monaden z. Korperwelt, in his Histor. philos. Abhandl., Leipzig, 1870, 4()9 
sq.. Stein, Leibniz u. Spinoza, Berlin, 1890, 158 sq., Dillmann, Fyiue n. Darstf/. 
d. Leibniz. Mftnadenlehre, Leipzig, 1891, 225 sq. For Leibnitz's theological 
use of Aristotle's f orms — er«7, — c/. TModicee, Pt. IIL, §§ 335-6, and J. H. v. 
Kirchmann's note 246 thereto, Band 80, p. 133, and note 62 f., Bd. 82, p. 87, of 
Iiis Philos. Bildiothek. Leipzig, 1879. On tlie elBo<; and ovaia. of Plato and Aris- 
totle, rf. Wallace, Outlines of the Philos. of Aristotle, §§ 10, 31, 32, .34, 37, and 
Zeller, Philos. d. Griech., II., i [Vol. 3], 658 sq., 4th ed. 1889, IL 2 [Vol. 4] , 304 
sq., 3d ed., 1879. For the Scholastic doctrine, rf. B. Haurcau, Histoire de la 
philos. scholastique, 2d ed., Paris, 1872-80; A. Stockl, Ge.sc/j. d. Philos. d. 
Mittelalte.rs, Mainz, 1862-66; G. Prantl, Geseh. d. Ijoe/ik im. Abendlande, Leip- 
zig, 18.55-1870, iiassim. Cf. also G. 1, 16, 22 sq., 4, 208. — Tr. 



SoO LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 



Th. True, but persous who study these matters rectify the 
popuhir notions. Assayers have found exact means of dis- 
cerning and separating the metals ; botanists have enriched 
Avonderfully the doctrine of plants, and the experiments made 
upon insects have opened for us a new path in the knowledge 
of animals, but we are still very far distant from the half of 
our course. 

§ 26. Ph. If species were a work of nature they could not 
be conceived so differently by different persons. Man appears 
to one person an animal without feathers, with two feet and 
with large nails, and another after a more profound exami- 
nation adds to these reason. Many people, however, deter- 
mine the species of animals by their external form rather than 
by their birth, since the question has been put more than once 
whether certain human /ceruses should be admitted to baptism or 
not, for the sole reason that their external configuration differed 
from the ordinary form of infants, without knoAving whether 
they were not as capable of reason as infants cast in another 
mould, some of whom are found, who, although of an approved 
form, are never able to exhibit during their eiitire life as much 
reason as appears in an ape or elephant, and who never give 
any indication of being governed by a rational soul. Whence 
it appears evident that the external form which alone has 
found mention, and not the faculty of reasoning which no one 
could know would be wanting in its time, has been regarded 
essential to the human species. And in these circumstances 
theologians and jurisconsults the most learned have been 
compelled to renounce their sacred definition of rational 
animal, and to put in its place some other essence of the 
human species. " Mr. Menage," (Menagiana Tom. I. p. 278, 
of the Dutch edition of 1694,)^ " furnishes us the example of a 
certain abbot of St. Martin, which deserves to be related. 
When this abbot of St. Martin, he says, came into the world, 
he had so little the figure of a man, that he resembled rather 
a monster. For some time they deliberated whether he 
should be baptized. He was baptized however, and declared a 
man provisionally, i.e. till time should show what he was. He 

1 Menagiana sive excerpta ex ore JEgiMi Menagii, 1st ed., 1 vol., 12mo, 
Paris, 1693, 3d ed.. enlarged and corrected by La Monnoye, Paris, 1715. Ei-d- 
niann, Jacques, and Scliaarscliniidt in liis German trans, erroneously read \M^. 
— Tr. 



cii. VI] ON HUMAN UNDERSTANDING 351 

was so disfigured by nature, that they called him all his life 
the Abbot Malotru. He was of Caen." There was a child 
who came very near being excluded from the human species 
simply because of his shape. He narrowly escaped as it was, 
and it is certain that a figure a little more deformed would 
have deprived him of it for ever and have caused him to 
perish as a being Avho ought not to pass for a man. Yet no 
reason can be given why a rational soul could not have been 
lodged in him, if the lineaments of his face had been a little 
more altered ; why a visage a little longer, or a flatter nose, or 
a wider mouth could not have subsisted as well as the rest of 
the irregular figure with a soul and with qualities which made 
him capable, wholly disfigured as he was, of being clothed 
Avitli dignity in the church. 

Til. Up to the present time, no rational animal has been 
found with an external figure very different from ours, there- 
fore, when the question arose of baptizing a child, race and 
figure have always been considered only as marks by which to 
judge whether it was a rational animal or not. Thus theo- 
logians and jurisconsults have never needed to renounce for 
that reason their sacred definition. 

§ 27. Ph. But if that monster, of which Licetus,^ Bk. I., 
chap. 3, speaks, with a man's head and a hog's body, or other 
monsters, with the heads of dogs and of horses, etc., upon the 
bodies of men had lived and could have spoken, the difficulty 
would be much greater. 

1 Fortunio Liceti, 1577-1657, a celebrated Italian physician and scholar, who 
taught logic at Pisa, 1600-1()09 ; philosophy at Padua till 1631 ; then philosophy 
at Bologna ; and finally, theoretic medicine at Padua from 1645 till his death. 
He was a great admirer of Aristotle, and wished to admit nothing beyond his 
doctrines, and thus contributed to render both philosophy and medicine sta- 
tionary. For the matter to which Leibnitz here refers, cf. Licetus, De spont.aneo 
riventiuin ortu, lib. qiuU., fol., Vicentire, IGIS, Bk. I., chap. 28, pp. 34-o6, Sexta 
confirniatio spontanei ortus hominum petita ex humanis figuris in belluis, ac 
lapidibus enodatur aperiendo talium figurarum caussas, in which chapter 
Licetus treats of various monsters, referring to his De monstrornni mentioned 
below, and to his father's, Giuseppe Liceti, an Italian physician, died 1599, 
Dialof/HS de rjenitalium. vsu et dignitate, or II Ceva, dell' ouvero eccellenza ed 
uso de' f/enitali, 1598, Dc monstrorum ccmssis, natura, et differentiis lib. duo, 
2d ed., 4to, Petavii, 1634, pp. 13, 183, 194 : " De monstrorum humanorum reale 
existentia} " ; the same, with additions by Gerard Blasius, 4to, Amstelodami, 
1665, ]^]^. 13, 183, 194 ; the same, in the French trans.. Traits des monslres, by 
Jean Palfyn, 1()50-1730, in his Description anatomique dc.s parties de lafemme 
qui servent a la (/eneration, etc., 4to, Leyden, 1708, pp. l.'i, 197, 208. —Tr. 



852 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

Th. I admit it, and if that occurred and if any one had done, 
as a certain writer, a monk of the olden time, named Hans 
Kalb (Jean le veau — John the calf) who ^ painted himself 
with a calf's head, the pen in his hand, in a book he had 
Avritten, which procedure caused some foolishly to think that 
this writer had in reality a calf's head, — if, I say, that hap- 
pened, we should be more cautious hereafter in getting rid of 
monsters. For there is some probability that reason would 
maintain it with theologians and with jurisconsults in spite of 
the figure and even in spite of the differences which the 
anatomy would furnish to the physicians, which would as 
little injure the quality of man as the reversal of the viscera 
in that man whose anatomy some persons of my acquaintance 
have seen at Paris, which has made some stir, in which nature 

' ' reu sage et sans doute en debauche 
riaga le foye au coste gauche 
Et de meme vice versa 
Le coeur a la droite pla^a," 

i.e. "unwise and doubtless in debauch placed the liver upon the 
left side and likewise vice versa the heart upon the right," 
if I rightly remember some of the verses which the late Mr. 
Alliot- the father (a famous physician because he passed as 
skilful in the treatment of cancers) showed me of his own 
making upon this prodigy. It is a matter of course, provided 
the variety of conformation does not go too far in the case 
of rational animals and that no return is made to the times 
when animals spoke, for then we should lose our especially 
peculiar advantage of reason ^ and should henceforth be more 
attentive to birth and the external in order to be able to dis- 

1 Erdraann and Jacques add " qui " after " le veau." — Tr. 

2 Pierre Alliot, a French physician of the seventeenth century, born at 
Bar-le-Duc, reputed to have great skill in the treatment of cancer and other 
malignant ulcers. His most distinguished patient was Anne of Austria, the 
mother of Louis XIV., whom he treated unsuccessfully in Paris in 1665. Not- 
withstanding his failure, he was appointed physician to the king. His published 
works include Theses medicse de motu sanguinis circulato et de morbis ex fere, 
Pont-a-Mousson, 1663, 8vo; Epistola de cancro apparente, and Nuntius profli- 
f/ati sine ferro et igne carcinomatis, both Bar-le-Duc, l(i()4, 12mo. His son, 
Jean Baptiste Alliot, was physician to Louis XIV., and published Traite du 
cancer oii Von expUqne sa nature et oil Von propose les moyens les plus surs 
pour le guerir methodiquement, Paris, 16',t8, 12mo. — Tr. 

3 The French text is: " nostre i^rivilege de la raison en preciput," etc. — Tr. 



cii. VI] ON HUMAN UNDEKSTANDING 353- 

cern those of Adam's race from those who may descend from 
a king or patriarch of some canton of apes in Africa ; and our 
learned author was right in his remark (§ 29) that if Balaam's 
ass had all her life discoursed as rationally as she did once 
with her master (supposing it was a prophetic vision), she 
would always have had difficulty in obtaining rank and a seat 
among women. 

Ph. You laugh, I see, and perhaps the author laughed also ; 
but, to speak seriously, you see that you cannot always assign 
fixed limits to species. 

Th. I have already agreed to this ; for when the question 
concerns fictions and the possibility of things, the passage 
from species to species may be insensible, and to discern them 
would sometimes be about as impossible as to decide how 
m uch hair a man must be allowed that he may not be bald. 
This indeterminateness would be true even when we knew 
perfectly the internal nature of the creatures under discussion. 
But I do not see that it can prevent things from having real 
essences independent of the understanding, and us from know- 
ing them. It is true that the names and limits of species 
Avould sometimes be like the names of measures and weights, 
where choice is necessary in order to have fixed limits. But 
ordinarily there is nothing of the kind to fear, species too 
much alike seldom occurring together. 

§ 28. Ph. It seems we agree here at bottom, although we 
differ somewhat in terms. I also admit that there is less 
arbitrariness in the denomination of substances than in the 
names of the mixed modes. For few venture to unite the 
bleating of a sheep with the figure of a horse, or the color of 
lead with the weight and fixedness of gold, and we prefer to 
draw copies after nature.^ 

Th. This is not so much because in substances regard is 
had only to that which exists effectively, as because there is no 
certainty in the case of physical ideas (which are not very 
thoroughly understood) that their union is possible and useful, 
if there is no actual existence to guarantee it. But this also 
takes place in the modes, not only when their obscurity is 
impenetrable by us, as sometimes happens in physics, but also 

^ That is, to follow experience in the formation of our ideas, and to conform 
our inner world in general to that furnished by nature. — Tk. 

2 A 



854 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

wheu it is difficult of penetration, enough examples of whicli 
occur in geometry. For in both of these sciences it is not 
within our power to make combinations according to our fancy, 
otherwise we should be right in speaking of regular decahedrons, 
and should seek in the semicircle^ a centre of magnitude, as 
there is in it a centre of gravity. For it is in fact surprising 
that the first is there, and that the second cannot be. Now 
while in the modes the combinations are not always arbitrary, 
we find on the other hand that in substances they sometimes 
are so ; and it often depends on ourselves to make combina- 
tions of qualities in order further to define substantial beings 
in advance of experience, when we understand enough of these 
qualities to judge of the possibility of the combination. Thus 
it is that expert gardeners in the orangery can rationally and 
successfully propose to produce some new species and give it 
a name in advance. 

§ 29. Pli. You will always agree with me that Avhen the 
question arises of defining species, the number of ideas com- 
bined depends upon the different application, industry, or fancy 
of the one forming this combination, as it is the figure which 
regulates most frequently the determination of the species of 
vegetables or animals, and likewise as regards the majority of 
natural bodies which are not produced by seeds, it is the color 
which is most strongly adhered to. § 30. In truth these are 
often only confused conceptions, gross and inexact, and it is 
very essential that men agree as to the precise number of 
simple ideas or qualities which belong to a given species or a 
given name, for pains, skill, and time are needed to find simple 
ideas which are constantly united. However a few of the 
qualities composing these inexact definitions are ordinarily 
sufficient in conversation ; but in spite of the stir about gen- 
era and species, the forms, of which so much has been said in 
the schools, are only chimeras which avail us nothing in fur- 
nishing an entrance into the knowledge of specific natures. 

Th. Whoever makes a possible combination, is not at all 
mistaken therein, nor in giving it a name ; but he is mistaken 

1 Such combinations of essentially self-contradictory ideas may easily be 
united in a complex term, and be apparently clear and possible, until analyzed 
and compared with reality, when their confusion and impossibilitj' is at once 
made evident. — Tr. 



CH. VI] ON HUMAN UNDERSTANDING 355 

if he thinks that his conception is altogether that which others 
more expert have conceived under the same name or in the 
same body. He perliaps conceives a genus too common instead 
of another more specific. There is nothing in all this contrary 
to the schools, and I do not see why you return here to the 
charge against genera, species, and forms, since it is necessary 
for you to recognize indeed the genera, species, and even the 
internal essences or forms, which we do not pretend to employ 
in order to know the specific nature of the thing, although we 
admit we are still ignorant of them. 

§ 30. Ph. It is at least evident that the limits we assign to 
species are not exactly conformed to those established by nature. 
For in our need of general names for present use, we do not 
put ourselves to the trouble of discovering the qualities which 
would give us superior knowledge of their most essential dif- 
ferences and agreements, but we ourselves distinguish them 
into species in virtue of certain appearances which are mani- 
fest to everybody, that we may more easily communicate with 
others. 

Th. If we combine compatible ideas, the limits we assign to 
species are always exactly conformed to nature ; and if we are 
careful to combine ideas actually found together, our notions 
are also conformed to experience ; and if we consider them 
as provisional only for actual bodies, without excluding ex- 
periment made or to be made for further discovery therein, 
and if we have recourse to experts, when a definite question 
arises with reference to what is openly understood by the 
name, we shall not err in the matter. Thus nature may 
furnish ideas the most perfect and most convenient, but she 
will not give the lie to those we have which are good and 
natural, although not perhaps the best and most natural. 

§ 32. Ph. Our generic ideas of substances, as that of metal, 
for example, do not follow exactly the models set them by 
nature, since you cannot find any body including simply malle- 
ability and fusibility without other qualities. 

Th. No one asks for such models and it would not be reason- 
able to ask for them ; furthermore they do not occur in the 
most distinct notions. We never find a number in which there 
is nothing to notice but multitude in general, an extension in 
which there is only extension, a body in which tlierc is only 



350 LEIBNITZ'S CRITIQUE OE LOCKE [bk. hi 

solidity, and no other qualities ; and when the specific differ- 
ences are positive and contrary it is very essential that the 
genus share in them. 

Ph. If, then, any one thinks that a man, a horse, an animal, 
a plant, etc., are distinguished by real essences made by nature, 
he must think that nature is very liberal icith these real essences, 
if she produces one of them for the body, another for the 
animal, and still another for the horse, and that she bestows 
freely all these essences upon Bucephalus ; whilst genera and 
species are only signs more or less comprehensive. 

TJi. If you take real essences as these substantial models, 
which exist as a body and nothing more, an animal and nothing 
more specific, a horse without individual qualities, you are 
right in treating them as chimeras. And no one has main- 
tained, I think, not even the greatest Realists of former times, 
that there are as many substances confining themselves to the 
generic as there are genera. But it does not follow that if 
general essences are not this, they are merely signs; for I have 
many times remarked to you that there are iwssibilities in the 
resemblances. In like manner from the fact that colors are not 
always substances or extracted dyes, it does not follow that 
they are imaginary. For the rest you cannot think nature too 
liberal; she is so beyond all that we can invent, and all advan- 
tageous compatible possibilities are found realized upon the 
grand theatre of her representations. There were formerly 
two axioms among philosophers : that of the Realists seemed 
to make nature prodigal, and that of the Nominalists seemed 
to declare her stingy. The one says that nature suffers no 
vacuum, and the other that she does nothing in vain. These 
two axioms are good provided you understand them ; for nature 
is like a good economist, who saves where it is necessary in 
order to be grand at times and places. She is grand in effects, 
and sparing in the causes she employs. 

§ 34. Ph. Without amusing ourselves longer with this dis- 
cussion upon real essences, it is enough that we obtain the pur- 
pose of language and the usage of words which is to indicate 
our thoughts in an abridged form. If I wish to speak to any 
one of a species of birds three or four feet in height, whose 
skin is covered with something between feathers and hair, of a 
dark brown color, without wings, but in their place two or 



cii. VI] ON HUMAN UNDERSTANDING 357 

three small branches, like those of the broom, which descend 
to the lower part of the body, with long and large legs, the 
feet armed only with three claws and witliout a tail ; I am 
compelled to make this description whereby I can make myself 
understood by others. But when I am told that the name of 
this animal is Cassowary, I can then use this name to designate 
in discourse this entire complex idea. 

Th. Perhaps a very exact idea of the covering of the skin 
or of some other part would suffice by itself alone to distin- 
guish this animal from every other known, as Hercules was 
known by his gait, and as the lion was recognized by his claw 
according to the Latin proverb. But the more circumstances 
you heap up, the less provisional is your definition. 

§ 35. Ph. We may curtail the idea in this case without 
prejudice to the thing; but when nature curtails it, it is a 
question whether the species remains. For example : if a 
body existed having all the qualities of gold except mallea- 
bility, would it be gold ? it depends upon men to decide. 
They are then the ones who determine the species of things. 

Til. Not at all ; they would determine only the name. But 
this experience would teach us that malleability has no neces- 
sary connection with the other cpialities of gold taken together. 
It would teach us then a new possibility and consecpiently a 
new species. As for gold which is eager ^ or brittle, this comes 
only from additions, and is not consistent with the other tests 
of gold; for the cupel and antimony remove this eagerness 
from it. 

§ 36. Ph. A portion of our doctrine follows that will appear 
very strange. Each abstract idea having a certain name forms 
a distinct species. But what of that, if nature so wills it ? I 
should be glad to know why a lap-dog and a greyhound are not 
as distinct species as a spaniel and an elephant. 

Th. I have distinguished above the different senses of the 
word species. Taking it logically, or mathematically rather, 
the least dissimilitude may suffice. Thus each different idea 
will give another species, and it makes no difference whether 
it has a name or not. But, physically speaking, we do not at- 
tend to all the varieties, and we speak either distinctly when the 
question concerns only appearances, or conjecturally when the 
1 Cf. Locke, riiilos. Works, Vol. 2, p. 05 (Bolin's ed.). — Tr. 



358 LEIBNITZ'S CRITIQUE OF LOCKE [uk. hi 

question concerns the inner truth of things, presuming therein 
some essential and immutable nature, like reason in man. 
We presume then, that whatever differs only by accidental 
changes, like water and ice, quicksilver in the liquid form and 
as sublimate, is of the same species : and in organic bodies the 
provisional mark of the same species is usually placed in the 
generation or race, as in those most alike it is placed in repro- 
duction. It is true we cannot judge with precision, for lack 
of knowledge of the inner nature of things ; but, as I have 
said more than once, we judge provisionally and often con- 
jecturally. But when we wish to speak only from the external, 
for fear of saying nothing certain, there is some latitude ; and 
to dispute then whether a difference is specific or not is to 
dispute about the name ; and in this sense there is so great a 
difference between dogs, that we may very well say that the 
house-dogs of England and the dogs of Boulogne belong to 
different species. It is not impossible, however, that they 
belong to a remote identical or similar race, which we should 
find if we could go back very far, and that their ancestors 
were alike or identical, but that after great changes, some of 
the posterity have become very large and others very small. 
We may indeed believe also without offending reason that 
they have in common an inner nature, constant, specific, which 
is no longer subdivided thus, or which is not found here in 
several other such natures, and consequently is no longer 
varied save by accidents; although there is also nothing to make 
us judge that this must necessarily be so in all that which we 
call the lowest species (species infima). But there is no likeli- 
hood that a spaniel and an elephant are of the same race, and 
that they have such a specific common nature. Thus in the 
different sorts of dogs, speaking of appearances, we may dis- 
tinguish species, and speaking of the inner essence we may be in 
suspense : but comparing the dog and the elephant there is no 
reason for attributing to them externally or internally that 
which would make us think them of one and the same species. 
So there is in this case no occasion for suspense in the face of 
the presumption. In man we can also distinguish species 
logically speaking, and if we stopped with the external we 
should find also, speaking physically, differences which could 
pass as specific. Thus a traveller was found who thought 



CI!. VI] ON HUMAN UNDERSTANDING 359 

that the Negroes, Chinese, and finally the Americans were not 
(tf one and the same race among tliemselves nor with the 
[it'oples resembling us. But as we know the essential inner 
luiture of man, i.e. the reason, which dwells in the man him- 
self and is found in all men, and as we notice nothing fixed 
and internal among us wlricli forms a subdivision, we have no 
reason to judge that there is in men, according to the truth of 
the inner nature, an essential specific difference, while such 
difference is found between man and beast, supposing that the 
beasts are only empirical, according as I have explained above, 
as in fact experience gives us no reason for forming any other 
judgment. 

§ 3d. Ph. Let us take the example of an artificial thing 
whose internal structure is known to us. A time-piece that 
only indicates the hours, and one that strikes, are of one 
species oiily for those who have only one name by which to 
designate them ; but for him who designates the first by the 
name watch, and second clock, they are in relation to liim dif- 
ferent species. It is the name and not the inner disposition 
which makes a new species, otherwise there would be too 
many species. There are watches with four wheels, and 
others with five ; some have strings and fusees,^ and some not ; 
some have a free balance, and others are regulated by a spiral 
spring and others by hog's bristles. Does any one of these 
things suffice to make a specific difference ? I say no, so 
long as these time-pieces agree in name. 

Th. And I for my part say yes, for without stopping at 
names, I should consider the varieties of contrivance and 
especially the differences of the balance ; for since a spring 
has been applied which governs the vibrations according to 
its own and consequently renders them more equal, pocket- 
watches have changed their character, and have become in- 
comparably more accurate. I have indeed mentioned before 
another principle of equality which might be applied to 
watches. 

Ph. If any one wishes to make divisions based upon the 
differences which. he knows in the internal configuration he 
may do so ; but they -would not be distinct species with rela- 
tion to the people who are ignorant of this construction. 

1 Locke has "physics," Philos. Works, Vol. 2, p. 07 (Bohn's eel.). — Tk. 



3G0 LEIBNITZ'S CKITIQUE OF LOCKE [uk. hi 

Th. I do uot know why those with you always wish to 
make virtues, truths, and species depend upon our opinion or 
knowledge. They exist in nature, whether we know it and 
approve or not. To speak otherwise is to change the names 
of things and received language without any reason. Men up 
to the present time have believed that there are many kinds 
of clocks or watches, without informing themselves in what 
they consist or how they may name them. 

Ph. You have however recognized not long since that when 
men wish to distinguish physical species by appearances, they 
limit them in an arbitrary way, where they find it to the pur- 
pose, i.e. according as they find the difference more or less 
considerable and according to the end they have. And you 
yourself have made use of the comparison of weights and 
measures, which are regulated and given their names accord- 
ing to the good pleasure of man. 

Th. It is since then that I have begun to understand you. 
Between specific differences purely logical, for w^iich the least 
variation of assignable definition suffices, however accidental 
it be, and between s])ecific differences purely ^ihysiccd, based 
upon the essential or immutable, we may place a mean, which 
cannot be precisely determined ; it is regulated by the most 
important appearances, which are not altogether immutable, 
but which do not change easily, the one approaching the 
essential more than the other. And as a connoisseur too may 
go farther than another, the thing appears arbitrary and has 
some relation to men, and it appears convenient to regulate 
names also according to these principal differences. We can 
then speak thus, that there are specific civil differences and 
nominal species which must not be confounded with what I 
have called above nominal definitions, and which have place 
in differences specifically logical as well as physical. For the 
rest, besides common usage, the laws themselves may give 
autliority to the significations of words, and then the species 
would become legal, as in the contracts which are called 
nominati, i.e., designated by a particular name. For example 
as the Roman Law made the age of puberty commence at the 
end of the fourteenth year. This entire consideration is not 
to be despised, but I do not see that it is of very much use 
here, for besides the fact that you have appeared to me to 



CH. VI] ON HUMAN UNDERSTANDING 361 

apply it sometimes where it did. not apply, we shall accom- 
plish nearly the same result if we consider that it rests with 
men to proceed in subdivisions as far as they find them to 
the purpose, and to abstract ulterior differences without the 
necessity of denying them ; and that it also rests with them 
to choose the certain, notwithstanding the vincertain, in order 
to fix some notions and measures by giving them names. 

Ph. I am much pleased that we are here no longer so far 
apart as we appeared. § 41. You agree then, sir, I see, that 
artificial as well as natural things are species contrary to the 
view of some philosophers. § 42. But before leaving the 
names of substances, I would add that of all the diverse ideas 
we have, they alone are ideas of substances which have proper 
or individual names ; for it rarely happens that men need to 
make frequent mention of any individual quality or other 
individual accident. Besides individual acts perish at once 
and the combination of circumstances which thereby comes 
about only subsists as in the substances. 

Th. There are, however, cases where it has been necessary 
to remember an individual accident and to give it a name ; 
thus your rule is ordinarily good, but there are exceptions to 
it. Religion furnishes us with them ; for example we cele- 
brate each year the memory of the birth of Jesus Christ. The 
Greeks call this event Theogeny, and that of the adoration of 
the Magi, Epiphany. And the HebreAvs call the Passah par 
excellence the passage of the angel who caused the death of 
the eldest sons of the Egyptians without touching those of the 
Hebrews ; and this is why they were to celebrate its memory 
every year. As for the species of artificial things, the scholastic 
philosophers found difficulty in admitting them into their p?-e- 
dicameyits ; but there was little necessity for their hesitation 
since these predicamental tables were destined for use in mak- 
ing a general review of our ideas. It is well however to rec- 
ognize the difference existing between perfect substances and 
between the assemblages of substances {aggregata) which are 
substantial entities composed either by nature or by the art of 
man. For nature has also such aggregates, as the bodies whose 
mixture is imperfect (imperfecte mixta) to use the language of 
our philosophers, which constitvite no unum per se and do not 
possess in themselves a perfect unity. I believe however that 



302 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

the four bodies which they call elements, and think simple, and 
the salts, metals, and other bodies which they think are per- 
fectly mixed, and to wliich they attribute their temperaments,^ 
are not unitm j)er se either; so much the more as we must 
judge that they are uniform and homogeneous only in appear- 
ance, and even a homogeneous body would not cease to be a 
mass. In a word, the perfect unity must be reserved to bodies 
animated, or endowed with primitive entelechies; for these 
entelechies are analogous to souls and are as individual and 
imperishable as they ; and I have elsewhere affirmed that their 
organic bodies are practically machines, but which surpass the 
artificial machines of our invention as much as the inventor of 
the natural machines surpasses us. For these natural machines 
are as imperishable as the souls themselves, and the animal 
with the soul subsists always : it is (the better to explain my- 
self by something pleasing, wholl}^ laughable as it is,) as if a 
harlequin wished to strip himself in the theatre, but could not 
succeed because he had an indefinite number of garments one 
upon another ; although these infinite replications of organic 
bodies, which exist in an animal, are not so similar nor so 
applied the one to the other, as the garments, nature's art 
being of a wholl}' different subtility. All this shows that the 
philosophers have not been wholly in the wrong in putting so 
great distance between artificial things and between natural 
bodies endowed with a real unity. But it belonged only to 
our time to develop this mystery and make understood its 
importance and consequences in order thoroughly to establish 
natural theology and what is called Pneumatics,- in a manner 

1 Leibnitz here alludes to the four elements of Empedocles, c. 492-c. 432, 
B. c, viz., fire, air, earth, water, adopted by Plato and Aristotle and called by 
the Perijmtetics warmth, cold, drj'ness, humidity, a mixture of which in vary- 
ing proi^ortions constituted all bodies. Cf. Zeller, Philos. d. Griec, I. 2 [Vol. 
2], 758 f;q., 5th ed., 1892, II. 1 [Vol. .3], 796" s^., 4th ed., 1889, U, 2 [^^ol. 4]. 431, 
sq., 832 sq., .3d ed., 1879. The state of a body resulting from the proportional 
disposition of these primary constituent elements or qualities was called its 
temperament, the character of the temperament varying according to the pre- 
dominance of one or more of the elements. The scholastics discussed the 
question whether the temperament comprised these four primary qualities, or 
whether it did not consist in a fifth simple quality, the outcome of the recipro- 
cal action of the four primary qualities, wliich resulted in their entire destruc- 
tion. Cf. also Gevhardt, Leibniz. philo-H. Schrift., 4, 207. — Tr. 

2 Cf. ante, p. .50, note 2. Schaarschmidt states that Pneumatics — Pneumatik 
— with the meaning — Doctrine of the Spirit, Ze/j re vom Geiste — Psychology 



CH. VI] ON HUMAN UNDERSTANDING 363 

truly natural and in agreement with our experiments and 
understanding, and requiring the loss of none of the important 
considerations they are destined to furnish, or rather enhanc- 
ing their value, as does the system of pre-established harmony.^ 
And I believe that we can best conclude this long discussion 
of the names of substances only by that means. 

— occurs in Alsted's Encyclopsedie, Herbornias, 1630, cf. ante, p. 311, note 2, and 
that Stephen Chauvin in his Lexicon philosophicum, Leovardiae, 1713, adopted 
it and explained it by Pneumatology and Piieumatosophy. The term is now 
confined to pliysical science, and denotes tliat department of hydrodynamics 
whicli treats of the properties of gases as distinguislied from liquids. Cf. 
Krauth-Flemmiug, Vocah. of the Pliilos. Sciences, p. 388, New York, Sheldon 
&Co., 1883. — Tk. 

1 Of. Meiv Essinjs, Bk. IV., chap. 10, §§ 7 and 9, hifra, pp.505, 507 ; Systeme 
noureau, §§ 14-10, Gerbardt, 4, 484-8(5, Erdmann, 127, a-128, Jacques, 1, 475-77, 
trans. Duncan, Philos. Wks. of Leibnitz, 77-79 ; Considerations sur les principes 
de vie, etc., G. 6, 541, E. 430, trans. D. 165; Principes de la nature et de la 
grace, §§ 7-13, G. 6, 602-(J04, E. 716, trans. D. 212-215; Animadversiones in 
partem yeneralem Principiorum Cartesianorum, Pt. I. ad Art. 14, G. 4, 358, 
trans. D. 50; Leibniz gegen Descartes und den Cartesianisrmis, G. 4, 292-294, 
401-403, 405-406, E. 176, trans. D. 132-138, and his note 49, p. 382 ; Med. de Cog. 
Ver. et Ideis, G. 4, 424, E. 80, a, trans. D. 30. According to Leibnitz, his 
doctrine of monads requires as its necessary complement the existence of God, 
since the single monads, expressing in their own experience all that is beyond 
them, yet without inliuence on other monads, cannot furnish a suiiicient 
ground or reason for the liarmony and connection of tilings in a universal 
world-order. This harmonious world-order existing, its sutiicient ground or 
reason must be found in the absolute being, God, who has given to each 
monad the nature which makes it capable of develojiing itself in its extreme 
individuality in accord and correspondence with every other. The pre-estab- 
lished harmony is thus an actual proof, in accord with experience, of the 
existence of God, and the suggestion of reason in the ontological argument as 
improved by Leibnitz, is confirmed by the comparative and comprehensive 
study of the phenomena of nature. For expositions and criticisms of Leibnitz's 
doctrine, cf. Dewey, Leibniz's Neio Essays, chaps. 11, 12; E. Zeller, Gesch. d. 
deutschen Philos. seit Leibniz, 2d ed., Miinchen, 1875, pp. 83-98, 124-127; F. A. 
Lange, Gesch. d. Mater ialismus, 3d ed., Leipzig u. Gerlohn, 1875 sq., Bk. I., 
Sect. IV., chap. 4, Eng. trans, by E. C. Thomas, 3 vols., Boston, Vol. 2, pp. 
124 sq. ; Kuno Fischer, Gesch. d. n. Philos., Bd. II., Leibniz, 3d ed., Heidelberg, 
1889, pp. 455 sq., 539 .s^. — Tr. 



804 LEIBNITZ'S CRITIQUE OF LOCKE [bic. 



CHAPTER VII 

OF PARTICLES 

§ 1. Ph. Besides the words which are used to name ideas, we 
need those which signify the connection of ideas or proposi- 
tions. This is, this is not, are general signs of affirmation or 
negation. But besides the parts of propositions the mind also 
binds together sentences and entire propositions, § 2. availing 
itself of words expressing this union of different affirmations 
and negations and which are called jmrticles ; in whose proper 
use the art of speaking well principally consists. It is in 
order that reasoning be consecutive and methodical that terms 
showing the connection, restriction, distinction, opposition, em- 
phasis, etc., are needed. And when they are despised the 
hearer is embarrassed. 

Th. I admit that particles are very useful ; but I am not 
aware that the art of speaking well consists principally in 
their proper use. If any one presents only aphorisms or 
detached theses, as they often do in the universities, or as in 
the case of that which they call among the jurisconsults an 
articulate libel, or as in the articles which are offered to the 
witnesses, then provided we arrange these propositions well 
we shall accomplish very nearly the same result in making 
them understood as if we had put in the connective and the 
particles ; for the reader supplies them. But I admit there 
would be trouble if you put in the particles badly, and much 
more than if you omitted them. Particles seem to me also 
to unite not only the parts of discourse composed of proposi- 
tions and the parts of the proposition composed of ideas, but 
also the parts of the idea, composed in mau}^ ways by the 
combination of other ideas. And it is this last connection 
which is indicated by the prepositions, while the adverbs 
modify the affirmation or negation in the verb ; and the con- 
junctions modify the connection of different affirmations or 
negations. But I doubt not that you have noticed all this 
yourself, although your words seem to state otherwise. 

§ 3. Ph. The part of grammar which treats of particles has 



CH. VII] ON HUMAN UNDERSTANDING 8G5 

been cultivated, less than tliat which represents in order the 
cases, genders, modes, tenses, gerundives, and supines. It is true 
that in some languages they have also arranged the particles 
under some titles by distinct subdivisions with great appear- 
ance of exactness. But it is not sufficient to run through 
these catalogues. One must reflect upon his own thoughts in 
order to observe the forms which the miud takes in discours- 
ing, for the particles are so many indications of the action of 
the mind. 

Th. It is very true that the doctrine of the particles is 
important, and I wish we might enter into much greater 
detail thereupon. For nothing would be more suited to make 
known the different forms of the understanding. Genders are 
of no account in philosophical grammar, but the cases corre- 
spond to the jirejiositions, and often the preposition is enveloped 
in the noun and as it were absorbed, and other particles are 
concealed in the inflections of the verbs. 

§ 4. Ph. In order properly to explain particles it is not 
sufficient to render them (as is usual in a dictionary) by the 
words of another language which approach most nearly their 
meaning, because it is as difficult to comprehend their precise 
meaning in one language as in another ; besides the significa- 
tions of related words in two languages are not always exactly 
the same and indeed they vary in one and the same language. 
I remember that in the Hebrew language there is one particle 
of a single letter^ of which there are reckoned up more than 
fifty significations. 

Th. Scholars have attempted to make special treatises upon 
the particles of the Latin, Greek, and Hebrew ; and Strauchius,^ 
a celebrated jurisconsult, has published a book upon the use 
of particles in jurisprudence, where their signification is of no 
small consequence. We ordinarily find, however, that it is 
rather by means of examples and synonymes that they attempt 
to explain them, than by distinct notions. Further we can 

1 I.e. the adverb h- — Tr. 

2 Johann Strauch, lf512-1680, the maternal iiiiclo of Leibnitz, a distinguished 
jurisconsult, Professor at Leipzii^, .lena, and Giessen, and Syndicus in Braun- 
si'liweig; cf. Gulirauer, G. W. Fraiherr v. Leibnitz, \'t. 1., Bk. I., pp. 0, 35 sq., 
and Annierkimf/en z. erst. BucJie, pp. (>, 7. The book here referred to by 
Jjoilniitz is entitled : Lexicon particulururn juris s. de usu et efficacia quor- 
nndam si/ncater/oreinatian ct partieularuin inderUnabiliurn. — Tr. 



30(5 LEIBNITZ'S CKITIQUE OF LOCKE [i;k. hi 

not always find a general or formal signification for them, as 
the late Bohlius ' called it, which can satisfy all the examples; 
but notwithstanding this we can always reduce all the uses of 
a Avord to a definite number of significations. And this is 
Avhat should be done. 

§ 5. Ph. In fact the number of significations greatly exceeds 
that of the particles. In English the particle hut has very differ- 
ent significations: (1) when I say: hut to say no more, {mats 
pour ne rieu dire de plus) as if this particle indicated that the 
mind stops in its course before it has reached the end. But 
saying : (2) I saw hut two planets (je vis seulement deux planetes), 
the mind restricts the sense of what it means to that which 
has been expressed by the exclusion of everything else. And 
when I say (3) : you pray, but it is not that God icould hring you 
to the true religion, hut that he tvould confirm you in your oivn 
(vous priez Dieu mais ce n'est pas qu'il veuille vous amener a 
la connaissance de la vraye Religion, mais qu'il vous confirme 
dans la vostre), the first hut (or mais) designates a supposition 
in the mind which is otherwise than it should be, and the 
second shows that the mind puts a direct opposition between 
what j)recedes and what follows. (4) All animals have sense, 
hut a dog is an animal (tous les animaux ont du sentiment, 
mais le chien est un animal). Here the particle signifies the 
connection of the second proposition with the first. 

Th. The French mais (but) may be substituted in all these 
instances except the second ; but the German ullein, taken as 
a particle, which signifies a kind of mixture of mais (but) and 
seulement (only), may doubtless be substituted instead of hut 
in all these examples except the last, where its use may be a 
little doubtful. Mais (but) is also rendered in German some- 
times by aber, sometimes by sondern, which indicates a sepa- 
ration or segregation and approaches the particle allein. For 
a proper explanation of the particles, it is not sufficient to 
make an abstract explication as we have just made here ; biit 
we must proceed to a paraphrase which may be substituted in 

1 Samuel Bohl, 1011-1689, Professor at Rostock, who devoted himself to the 
furtherance of the study of Hebrew in Germany, and whom Leibnitz mentions 
because of his works on the doctrine of the Hebrew Vowel- and Accent-Signs ; 
cf. Duteus, Leibniz, op. om., 5, 190. He published a large number of works, 
among which were Scrutin. S. s. ex accentibus, 1G36, and Dissertat. pro for- 
niali Si'jnif. S. S. eruenda, Rostock, 1637. — Tk. 



cn. VII] ON HUMAN UNDERSTANDING 367 

its place, as the definition may be put in the phxce of the thing 
defined. When we have striven to seek and to determine 
these suitable paraphrases, in all the particles so far as they 
are susceptible of them, we shall have regulated their sig- 
nifications. Let us try to attain this result in our four ex- 
amples. In the first we mean: Thus far only speak we of 
this, and no farther {iion piu) ; in the second : I see only two 
}ilanets, and no more ; in the third : You pray God, and for 
this only, viz. to be confirmed in your religion, and no more, 
etc. ; in the fourth, it is as if we said : all animals have sense ; 
it is sufficient to consider that only, and no more is needed. 
'I'he dog is an animal, he then has sense. Thus all these 
examples indicate limits, and a non plus ultra, whether in 
things, or in discourse. Thus hut is an end, a limit of the 
course, as if we said : stop, we are there, we have reached our 
But. But, Bute, is an old Teutonic word, signifying some- 
thing fixed, an abode. Beuten (an obsolete word found still in 
some church songs) is to abide. Mais originates from magis, 
as if any one wished to say : as for the surplus we mxist leave it, 
which is the same as saying : No more is needed, it is enough, 
let us come to something else, or this is something else. But 
as the use of languages varies in a strange manner, it would be 
necessary to enter much farther into the detail of examples in 
order sufficiently to regulate the significations of particles. In 
French we avoid the double mais by a cependant (however), and 
we should say: Vous priez, cependant ce n'est pas pour obtenir 
la verity, mais pour estre confirme dans vostre opinion (You 
pray, not however {cependant) to obtain the truth but (mais) 
to be confirmed in your opinion). The sed of the Latins was 
often expressed formerly by ains, which is the anzi of the 
Italians, and the French in modifying it have deprived their 
language of an advantageous expression. For example : There 
was no certainty about it, yet {cep)endanl) we were persuaded 
of what I have informed you, because we like to believe 
Avhat we wish ; but it has been found that it was not so ; but 
{ains) rather, etc. (II n'y avoit rien de seur, cependant on estoit 
persuade de ce que je vous ay mand^, parce qu'on aime a croire 
ce qu'on souhaite ; mais il s'est trouv6 que ce n'estoit pas 
cela; ains plustost, etc.). 

§ 6. Ph. My purpose has been to touch this matter only 



3fi8 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

very slightly. I would add that particles often include either 
constantly or in certain constructions the sense of an entire 
proposition. 

Th. But when it is a comjjlete sentiment, I think that it is 
only by means of a kind of ellipsis ; otherwise it is the inter- 
jections alone which in my opinion can subsist by themselves 
and say all in a word, as ah! (Jiol me!). For when we say 
mats, adding nothing more, it is an ellipsis for : hut let us tvait 
for the confirmation of intelligence and not flatter ourselves 
unduly. There is something approximating to this in the nisi 
of the Latins : si nisi non esset, if there were not but (mais). 
For the rest I should not be displeased, sir, had you entered a 
little farther into the detail of the turns of the mind which 
appear marvellous in the use of the particles. But since we 
have reason for hastening to conclude this investigation of 
words and to return to things, I do not wish to delay you 
longer, although I truly think that languages are the best 
mirrors of the human mind, and that an exact analysis of the 
signification of words would show us better than anything else 
the workings of the understanding:. 



CHAPTER VIII 

OF ABSTRACT AND CONCRETE TERMS 

§ 1. Ph. It is further to be remarked that terms are 
abstract or concrete. Each abstract idea is distinct, so that of 
two the one can never be the other. The mind must perceive 
by its intuitive knowledge the difference between them, and 
consequently two of these ideas can never be affirmed one of 
another. Every one sees at once the falsehood of these propo- 
sitions : humanity is animality or rationality : this is as evident 
as any of the generally received maxims. 

Th. There is still something to be said thereupon. We 
admit that justice is a virtue, a habit (habitus), a quality, an 
accident, etc. Thus two abstract terras may be stated one of 
another. I am furthermore wont to distinguish two kinds of 
abstracts. There are abstract logical terms, and there are 
also abstract real terms. The abstract real terms, or conceived 



I 



CH. IX] ON HUMAN UNDERSTANDING 369 

at least as real, are eitlier essences or parts of the essence, or 
accidents, i.e. beings added to substance. The abstract logical 
terms are the predications reduced to terms, as if I said: to be 
a man, to be an animal; and in this sense the one can be 
stated of the other, by saying : to be a man is to be an animal. 
But in the realities this has no place. For we cannot say that 
humanity or man-ness ^ {Vhommcite) — (if you please), which is 
the essence of the whole man, is animality, which is only a 
part of this essence ; yet these abstract and incomplete beings 
signified by the abstract real terms have also their genera and 
species which are not less expressed by the abstract real terms : 
thus there is predication between them, as I have shown by 
the example of justice and virtue. 

§ 2. Ph. One may always say that substances have only 
few abstract names ; they have scarcely spoken in the schools 
of humanity, animality, corporality ; and they have never been 
authorized in the world. 

Til. The reason is that but few of these terms were necessary 
to serve as examples and to throw light upon the general no- 
tion, which was the reason why they were not wholly neglected. 
If the ancients did not use the word Immcmity in the sense of 
the schools, they said human nature, which is the same thing. 
It is certain also that they said divinity, or rather divine 
nature ; and theologians having found it needful to speak of 
these two natures and of real accidents, they were attached to 
these abstract entities in the schools of philosophy and the- 
ology, and perhaps to a greater extent than was proper. 



CHAPTER IX 

OF THE IMPERFECTIONS OF WORDS 

§ 1. Ph. We have already spoken of the dotible use of ivords. 
The one is to register our own thoughts in order to aid our 
memory which makes us talk to ourselves ; the other is to 
communicate our thoughts to others by means of speech. 

1 I have taken the liberty to coin the word as an equivalent of the French, 
which I think is also coined by Leibnitz to express the abstraction of the 
scholastics. — Tr. 
2b 



870 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

These two uses show the perfection or imperfection of words. 
§ 2. When we speak only to ourselves, it is a matter of indif- 
ference what words Ave employ, provided we remember their 
meaning and do not change it. But § 3. the use of communication 
is also of two kinds, civil and philosophic. The civil consists 
in the conversation and use of the civil life. The pTdlosophic 
use is that made of words for the purpose of giving precise 
notions and to express in general propositions certain truths. 

Th. Very good: words are not less marks (notce) for us 
(as the characters of arithmetic or algebra may be) than signs 
for others ; and the use of words as of signs is as much in 
place when the question concerns the application of general- 
precepts to the usage of life, as when it concerns the discovery 
or verification of these precepts. The first use of signs is civil, 
and the second philosophic. 

§ 5. Ph. Xow it is difficult, chiefly in the following cases, 
to learn and retain the idea which each word signifies, (1) 
when these ideas are very complex; (2) when the ideas com- 
posing a new one have no natural bond between them, so that 
there is in nature no fixed measure nor any model to rectify and 
regulate them ; (3) when the model is not easy to be known ; 
(4) when the meaning of the word and the real essence are 
not exactly the same. The names of the modes are most lia- 
ble to be doubtful and imperfect for the two first reasons, and 
those of substances for the two second. § 6. When the idea 
of the modes is very complex, as that of the majority of the 
terms of ethics, they rarely have precisely the same significa- 
tion in the minds of tAvo different persons. § 7. The defect 
also of the models renders these words equivocal. He who 
first invented the word hrusquer (to be abrupt with) understood 
thereby what he found to the purpose, Avithout informing those 
Avho have used it as he of his precise meaning, and Avithout 
having shoAvn them any constant model. § 8. Common use 
regulates sufficiently the sense of Avords for ordinary couA^ersa- 
tion, but it has no precision ; and the signification most con- 
formed to the peculiar nature of the language is every day 
disputed. Many speak of glory, but few have the same under- 
standing of it. § 9. They are only simple sounds in the 
mouths of many, or at least their meanings are very indefinite. 
And in a discourse or conversation in which mention is made 



cii. IX] ON HUMAN UNDERSTANDING 371 

i)f honor, faith, grace, religion, the chicrch, and above all in dis- 
cussion, you will notice at once tliat men have different notions 
which they apply to the same terms. And if it is difficult to 
understand the meaning of the terms of the people of our 
time, it is much more difficult to understand ancient books. 
Fortunate is it that we may pass them by save when they 
contain what we should believe and do. 

Th. These remarks are good : but in regard to ancient books, 
as we need to understand Holy Scripture above all, and as 
lloman laws are still of great use in a good part of Europe, we 
are indeed compelled to consult a great many other ancient 
hooks; the Rabbis, the Church Fathers, even the profane his- 
torians. Besides the ancient physicians also deserve to be 
understood. The practice of medicine by the Greeks came 
through the Arabs to us ; the water from the fountain has been 
made turbid in the streams of the Arabs, and purified in many 
respects since we have begun to have recourse to the original 
Greeks. But these Arabs do not cease to be of use and we are as- 
sured that Ebenbitar,^ for example, who in his books on Simples 
has copied Dioscorides, often serves to throw light upon him. I 
find also that, next to religion and history, it is chiefly in medi- 
cine, as far as it is empirical, that the tradition of the ancients 
preserved in writing, and in general the observations of another 

1 Ibn-al-Baitar, c. 1197-1248, a distinguislied Arabian botanist, — according 
to Pouchet the most learned that the Arabian School has produced, — who 
wrote a general history of simples, or of plants alphabetically arranged, a 
materia medica, based upon and said to contain for the most part the woi'k of 
tlie Greek physician Dioscorides, c. 100 a.d., Uepl 'yatj? "laTpiK^^, as well as a 
variety of facts from other sources, including descriptions of plants not men- 
tioned by either Dioscorides or Pliny the Elder, 23-79. Most of 15aitar's 
works still remain in MSS. in the libraries of Paris and the Escurial. Fr. R. 
l>if!tz; published a small fragment of the work on Simples in his Analecta me- 
(Hca ex librls Mti.S., Lipsiae, ISoS, 8vo. There are also Grosse Zusammenstel- 
liing a. d. Krdfte d. bekannt. einfachen Heil-und-Nahrxmrismittel v. . . . Ebn 
Jlaithar. Aus d. Arahisdien ilhersp.tzt v. Dr. Joseph v. Sontheimer, 2 vols., 
Stuttgart, lcS40-i2, and Traite dea simplen, trans, by L. Leclero, in lust, de 
Prance, Noti(;es et extraits des MSS. de la Bibl. Nationale, vol. 23, Pt. I., Paris, 
1.S77, Ito. For some account of Baitar, ef. Leclerc in Gazette, hehdom. de medi- 
cine et de chirurgie,xxn.,97, 129, Paris, 1875; F. A. Pouchet, Ilistoire des sciences 
n.atureUes au moyen due, Paris, 185,3, 8vo. Schaarschmidt says that Jjoibnitz 
)nay have been led to the remark which he here makes u))ou liaitar by the 
Ex.eridttitiones de hornoni/inis Jii/les iatr/rm, appemleil to Claud. Salniasius, 
158S-1()53, Pllnianx exereitaliones, P. 104. a. V>. 110. a. A., Trajecti-ad-Iiheuum, 
1689, 2 vols., fol., where different accounts of Dioscorides are amended from 
Ebnl)itar. — Tr. 



372 LEIBNITZ'S ClUrKiUF. OF LOCKP: [isk. hi 

may be of service. I have therefore always held in high 
esteem physicians much versed in the knowledge of antiquity ; 
and I was very sorry that Keiuesius/ excellent in both depart- 
ments (of knowledge), had turned aside to explain the rites 
and history of the ancients, rather than to recover a part of 
the knowledge they had of nature, in which it has been shown 
that he would have been able furthermore marvellously to suc- 
ceed. When the Latins, Greeks, Hebrews and Arabs shall 
some day be exhausted, the Chinese, supplied also with ancient 
books, will enter the lists and furnish matter for the curiosity 
of our critics. IS"ot to speak of some old books of the Persians, 
Armenians, Copts and Brahmins, which will be unearthed in 
time so as not to neglect any light antiquity may give on doc- 
trines by tradition and on facts by history. And if there were 
no longer an ancient book to examine, languages would take 
the place of books and they are the most ancient monuments 
of mankind. In time all the languages of the world will be 
recorded and placed in the dictionaries and grammars, and 
compared together ; this Avill be of very great use both for the 
knowledge of things, since names often correspond to their 
properties (as is seen by the names of plants among different 
peojDles), and for the knowledge of our mind and the wonder- 
ful variety of its operations. Kot to speak of the origin of 
nations, which is known by means of solid etymologies which 
the comparison of languages will best furnish. But of this I 
have already spoken. And all this shows the use and extent 
of criticism, little considered by some otherwise very clever 
philosophers who take the liberty to speak with contempt of 
Rabhinage- and in general of ^^liilology. We see also that 
critics will find for a long time yet matter for fruitful exercise, 

1 Thomas Reinesius, 1587-1667, a physician who wrote on natural history 
and medicine, and afterwards devoted himself to philological and antiquarian 
studies. ■ Among his works were, Schola jureconsultorum medica relationum 
lihriH aliquot comprehensa, qidhus principia medicinsR in jus transmiita ex 
professo examinantiir, Lipsife, 1679, 12mo; Syntazma inscriptionem antiqiiantm 
cum primis Romie veteris, quarum. omiasa est recensio in Grvteii opere, cum 
comment, Lipsife, 1682, fol. Cf. B. Schuchardt, Lebensbeschreibun(/e7i be- 
riihmter y£rzte und Naturforscher, welche aus Thiiringen stammen. Corre- 
spondenz-BI litter des allgemeinen drztlichen Vereinsvon Thiirinc/en, Weimar, 
1888, xvii., 556, 601.— Tr. 

2 A term of disparagement, meaning the study made of the hooks of the 
rabhis. — Tr. 



cii. IX] ON HUMAN UNDERSTANDING 373 

and tliey will do well not to amuse themselves too much with 
niinutite, since they have so many objects more pleasijig for 
treatment ; though I well know that minutiee also are often very 
necessary with the critics for the discovery of more important 
knowledge. And as criticism turns in large measure upon the 
meaning of words and the interpretation of authors, especially 
the ancients, this discussion about words joined with the men- 
tion you made of the ancients, makes me touch upon this 
important point. But to return to your four defects of nomi- 
nation, I tell you, sir, that we can remedy them all, especially 
since writing has been invented and they subsist only through 
our negligence. For it depends upon us to fix their meanings, 
at least in any scholarly language, and to agree to destroy this 
tower of Babel. But there are two defects where the remedy 
is more difficult, consisting the one in the doubt which exists 
whether the ideas are compatible, when experience does not 
furnish them all combined in one and the same subject ; the 
other in the necessity for making provisional definitions of 
sensible things, when our experience with them is insufficient 
for more complete definitions : but I have spoken more than 
once of both these defects.^ 

Ph. [I am going to tell you some things which will serve 
further to clear up to some extent the defects you have just 
remarked, and the third of those which I have indicated 
makes it seem that these definitions are provisional ; viz. : — 
when we have no sufficient knowledge of our sensible models, 
i.e. the substantial beings of corporeal nature. This defect 
also makes us ignorant as to whether we may combine the 
sensible qualities which nature has not combined, because at 
l)ottom we do not understand them.] Now if the signification 
of the words which serve for the mixed modes is uncertain, 
for lack of models which show the same composition, that of 
the names of the substantial beings is uncertain for a wholly 
contrary reason, because they must signify what is supposed to 
be conformed to the reality of things, and to be related to the 
models formed by nature. 

Th. I have already more than once remarked in our pre- 
vious conversations that this is not essential to the ideas of 

1 Cf. New E.ssin/K, Bk. III., chap. (i. — Te. 



374 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

substances ; but I admit that ideas made after nature are the 
surest and most useful. 

§ 12. Ph. When then we follow the models wholly made 
by nature, unless the imagination finds it necessary to retain 
their representations, the names of substances have in ordi- 
nary use a double relation, as I have already shown. The 
Jirst is that they signify the internal and real constitution of 
things, but this model cannot be known and consequently can- 
not serve to regulate the significations. 

Th. That is not the question here, since we are speaking of 
ideas of which we have models ; the internal essence is in the 
thing, biit we agree that it cannot serve as a pattern. 

§ 13. Ph. The second relation is then that which the names 
of substances immediately have to the simple ideas, which 
exist at the same time in the substance. But as the number 
of these ideas united in one and the same subject is great, men 
speak of this same subject, forming very different ideas of it, 
both by the different combination of the simple ideas they 
make and because the greater part of the qualities of bodies 
are the powers which they have of producing changes in 
other bodies and receiving them ; witness the changes one of 
the basest metals is capable of undergoing through the opera- 
tion of fire, and it receives many more yet at the hands of a 
chemist, through the application of other bodies. Further, one 
is contented with weight and color as criteria for a knowledge 
of gold ; another includes ductility, fixedness ; and the third 
desires to make us take into consideration its solubility in 
aqua regia. § 14. As things likewise often resemble each 
other, it is sometimes difficult to designate their precise 
differences. 

Th. As bodies are really liable to be altered, disguised, 
falsified, counterfeited, it is a great point to be able to dis- 
tinguish and recognize them. Gold is disguised in solution, 
but it may be drawn off, either by precipitating it or dis- 
tilling the water ; and counterfeit or adulterated gold is 
recognized or purified by the art of the assayers, which not 
being known to everybody, it is not strange that men do not 
all have the same idea of gold. And ordinarily it is only 
the experts who have sufficiently just ideas of these mat- 
ters. 



CH. IX] ON HUMAN UNDErxSTANDING 375 

§ 15. Ph. This variety does not, however, cause so mi;ch 
confusion in civil intercourse as in philosophic researches. 

Th. It would be more tolerable if it had no influence in prac- 
tical life where it is often important not to receive a Qui pro 
quo, and consequently to know the characteristics of things or 
to have at hand the class who know them. And it is especially 
important as regards drugs and materials which are costly, and 
of which you may have need on important occasions. The 
philosophical confusion will manifest itself rather in the use 
of more general terms. 

§ 18. Ph. The names of simple ideas are less liable to equivo- 
cation, and we are rarely mistaken as regards the terms white, 
bitter, etc. 

Th. It is, however, true that these terms are not wholly 
exempt from uncertainty ; and I have already noticed the 
example of neighboring colors which are within the confines of 
two species and whose species is doubtful. 

§ 19. Ph. After the names of simple ideas, those of the simple 
modes are least doubtful, as for example, those of figures and 
numbers. But, § 20. the mixed modes and substances cause all 
the trouble. § 21. Men will say that instead of imputing 
these imperfections to the words, we should rather put them 
to the account of our understanding ; but I reply that w^ords 
interpose themselves to such an extent between our mind and 
the truth of things, that we may compare them with the 
medium, across which pass the rays from visible objects, and 
which often spreads a mist before our eyes ; and I have tried 
to think that, if the imperfections of language were more 
thoroughly examined, the majority of the disputes would cease 
of themselves, and the way to knowledge and perhaps to peace 
would be more open to men. 

Th. I think we could succeed from this time in written dis- 
cussions, if men would agree upon certain rules and execute 
them with care. But in order to proceed exactly viva voce and 
at once, some change in the language would be necessary. I 
have elsewhere ' entered upon this enquiry. 

1 In his writiniis in fnrthfiranee of his plan for the estahlisliment of a General 
Cliaracteristic or Philosojihical I^angna.^e, Sp^ciease f/eii^ralc, a project wiiieh 
Leibnitz had very mneli at heart, as appears from his frequent alhision to the 
subject, and upon wliich throughout his entire life he spent mucli labor, chiefly 



37(5 LETRMTZ'S ClIITTQUE OF LOCKE [bk. hi 

§ 22. Ph. While waiting for tins reform which will not be 
ready very soon, this uncertainty regarding words should teach 
us to be moderate, especially when it is a question of imposing 
upon others the sense attributed by us to the ancient authors, 
since in the Greek authors it is found that nearly every one 
speaks a different language, 

Th. I have been rather surprised to see that Greek authors 
so distant from one another in time and place, as Homer, 
Herodotus, Strabo, Plutarch, Lucian, Eusebius, Procopius, 
Photius, approach so closely, while the Latins have changed 
so much, and the Germans, English, and French much more. 
But the fact is, the Greeks since Homer's time, and still 
more when Athens was in a flourishing condition, had good 
authors which posterity has taken as models, at least in writ- 
ing. For no doubt the common language of the Greeks must 
have been much changed already under the rule of the Eomans. 
And this same reason accounts for the fact that the Italian 
has not suffered so great a change as the French, because the 
Italians, having had earlier writers of durable reputation, imi- 
tated and moreover esteemed Dante, Petrarch, Boccaccio, and 
other authors at a time when those of the French were no 
longer appreciated. 

CHAPTEPv X 

OF THE ABUSE OF WORDS 

§ 1. Ph. Besides the natural imperfections of language, 
there are some that are voluntary and arise from negligence, and 
it is an abuse of words to use them so badly. The first and most 
i:)alpable abuse is, § 2. that we attach no clear idea to them. Of 
these words there are two classes : the first have never had 
any definite idea, either in their origin or ordinary use. For 
the most part philosophical and religious sects have introduced 

preparatory, and with little positive results in accomplishing his plan. Cf. 
N<m Essays, Bk. IV. chap. G, § 2, Th., chap. 17, § 1:5, Th.; Gerhardt, Leibniz, 
philos. Schrift., 3, 216; 4, 27 sq., Erdmann, 6 sq.; G. 7, 3 sq., E. 82 sq., 669 sq.; 
Trendelenburg, Ueber Leibniz. Entivurf einer allgemeinen Characteristik, in 
his Histor. Beitrdge z. Philos., vol. 3, pp. 1 sq., Berlin, 1867; L. Neff, G. W. 
Leibniz als Sprachf or seller und Etymologe, Pt. II., pp. 13 sq., Heidelberg, 
1870-1.— Tr. 



cii. X] ON HUMAN UNDERSTANDING 377 

them in order to support some strange opinion, or to conceal 
some weak place in their system. They are, however, distin- 
guishing characters in the moutli of members of the party. 
§ 3. There are other words, which in their first and common 
use have some clear idea, but which have since been appro- 
priated to very important matters without attaching to them 
any certain idea. In this way the words wisdom, glory, grace, 
are often in the mouths of men. 

Th. I believe that insignificant words are less in number 
than you think, and that with a little care and good will you 
can fill up their void or fix their indefiniteness. Wisdom 
appears to be nothing else than the science of happiness. 
Grace is a favor done to those who do not deserve it aird who 
find themselves in a state where they need it. And glory is 
the fame of the excellence of some one. 

§ 4. Ph. I do not wish now to examine whether there is 
anything to be said in regard to these definitions, but rather to 
notice the causes of the abuse of words. In the first place, we 
learn the words before we learn the ideas belonging to them, and 
children accustomed thereto from the cradle use them in like 
manner during their whole life : the more as they do not cease 
to make themselves understood in conversation, without ever 
having fixed their idea, by using different expressions in order 
to make others understand their meaning. This, however, often 
fills their discourses with a quantity of vain sounds, especially 
in matters concerning morals. Men take the words they find 
in use among their • neighbors, and in order not to appear 
ignorant of their meaning employ them confidently without 
giving them a certain sense : and, as in this kind of discourse 
they are rarely in the right, they are also rarely convinced 
that they are wrong; and to wish to draw them from their 
error is to wish to dispossess a vagabond. 

Th. Men in fact take so rarely the necessary trouble to 
understand terms or words that I have more than once been 
astonished that children can learn languages so soon, and that 
men furthermore speak them so accurately ; a view to which 
we attach so little in instructing children in their mother 
tongue and which others think of so little in acquiring clear 
definitions; the more so as those we learn in the schools do 
not ordinarily concern the words in public use. For the rest, I 



378 LEinXlTZ'S CRITIQUE OF LOCKE [p.k. in 

admit that men frequently happen to be wrong when indeed 
they discuss seriously and speak in accord with their feeling ; 
but I have also remarked often enough that in their speculative 
discussions upon matters within the province of their mind, 
they have every reason for two sides, except in the oppositions 
they make to each other where they misconstrue another's 
view. This arises from the bad use of terms and sometimes 
also from a spirit of contradiction and affectation of superi- 
ority. 

§ 5. Ph. In the second place the use of words is sometimes 
inconstant, a practice only too general among scholars. It is 
nevertheless a plain cheat, and if voluntary, is folly or malice. 
If any one so conducted himself in his accounts (as to take an 
X for a V), who, I pray, would have anything to do with 
him ? 

Th. This abuse being so common not only among scholars 
but also in the Avorld at large, I believe that it is due rather to 
bad custom and inadvertence than to malice. Usually the 
different significations of the same word have some affinity ; 
this makes one pass for another and does not give time to con- 
sider what is said with all the precision that is desirable. We 
are accustomed to tropes and figures, and some elegance or 
brilliant falsehood easily imposes upon us. For we oftener 
seek pleasvire, amusement, and appearance, than truth ; besides, 
vanity mixes itself therein. 

§ 6. PJi. TJie third abuse is an affected obscurity, either by 
giving terms in use unusual meanings, or by introducing neiv 
terms without explaining them. The ancient Sophists, whom 
Lucian ridicules so properly, pretending to speak of every- 
thing, covered their ignorance under the veil of the obscurity 
of words. Among the sects of philosophers the Peripatetic 
has shown itself remarkable by this defect; but the other 
sects, even among the moderns, are not wholly exempt from it. 
For example, the people who abuse the term extension, and 
find it necessary to confuse it with that of body. § 7. Logic 
or the art of discussion, which is held in such high esteem, 
has helped to maintain this obscurity. § 8. Those who 
have given themselves uj) to it have been useless or rather 
detrimental to the state ; § 9. while mechanics, though de- 
spised by the learned, have been serviceable to human life. 



CH. x] ON HUMAN UNDERSTANDING 379 

But these obscure doctors have been admired by the ignorant ; 
and they have been thought invincible because provided with 
briers and thorns, into which it was no pleasure to thrust one's 
self, their obscurity alone serving as a defence of their absurd- 
ity. § 12. The evil is that this art of obscuring words has 
confused the great rules of men's action, religion and justice. 

Th. Your complaint is largely just : it is nevertheless true 
that there are, though rarely, pardonable and even praiseworthy 
obscurities, as when we profess to be enigmatical, and the 
enigma is timely. Pythagoras ' so used it, and it is frequently 
the manner of the Orientals. The alchemists, who are called 
adepts, declare that they wish to be understood only by the 
sons of the art. And that would be well, if these pretended 
sons of the art had the key to the cipher. A certain obscurity 
may be allowed; but something must be concealed which is 
worth divining, and the enigma must be decipherable. But 
religion and justice demand clear ideas. It seems that the 
little order brought into their teaching has made the confusion 
in their doctrine ; and the indeterminateness of the terms is 
perhaps more harmful than their obscurity. Now as logic is 
the art which teaches the order and connection of thoughts, I 
do not see any reason for blaming it. On the contrary it is for 
want of logic that men deceive themselves.^ 

§ 14. Ph. The fourth abuse is when we take words for things, 
i.e. believe that the terms correspond to the real essence of the 



1 Pythagoras, c. 580-570-c. 500 b.c. The reference is to his so-called Symbols, 
or sayings preserved in a symbolic form, in order that their meaning might be 
concealed from the uninitiated, and the characteristic of which is the union of 
an ethical prescript with an external action relatively indifferent. Cf. Dioge- 
nes Laertius, Be vitis, dor/matibus, et apophthegmatis clarontmphilosoi/horum, 
VIII, 17 sq., who gives some of these symbols with interpretations of a part of 
them ; Zeller, Philos. d. Griec, 5th ed., 1892, Vol. 1, p. .324, note 2, 4(j2. MiiUach, 
Frcujmt. Pliilot^. Grsec, Vol. 1, p. 504 sq., gives a collection of these sayings. 
Examples are: "Carry not the image of God in the finger-ring," "Stir not 
t'le fire with the sword," " Sacrifice and pray with bare feet." Gottling, 
Gcsammlt. AbhatulL, Vol. 1, p. 278 sq., 2, 280 sq., has given them a " pene- 
trating investigation," on wliich see the note of Zeller above cited. Leibnitz 
on Pythagoras, (/. Gerhardt, Leibniz, philos. Schri/t., 7, 147. — Tr. 

2 Leibnitz, while rejecting the over-refinements of the scholastic logic, never- 
theless rightly values formal logic as an aid to clear thinking and correct 
reasoning. Cf. the letter to Gabriel Wagner, 1696, Gerhardt, Leibniz, philos. 
Schri/t., 7, 512 sq., Erdmann, 418 sq., Guhrauer, Leibniz, deutsche Schri/t., 1, 
374 sq., Berlin, 1838. — Tr. 



SSO LEIBNITZ'S CRITIQUE OF LOCKE [bk. in 

substances. Who is there brought up in the Peripatetic phi- 
losophy Avho does not think that the ten names which represent 
the jiredkainents are exactly conformed to the nature of things; 
that tho substanddl forms, vegetative soids,abhorrenceofa vacuum, 
intentional species, etc., are something real ? The Platonists 
have their soul of the world, and the Epicureans the tendency of 
their atoms towards movement at the time when they are at 
rest. If the aericd or ethereal vehicles ^ of Dr. More had pre- 
vailed in any corner of the world they would have been thought 
no less real. 

Th. Properly speaking this is not to take words for things, 
but to believe that true which is not so, an error too common 
with all men, depending not alone upon the abuse of words, 
but consisting in something entirely different. The design 
of the pre('7i''coHie»^s is a very useful one, and we ought to 
think of rectifying rather than of rejecting them. Substances, 
quantities, qualities, actions or passions, and relations, i.e. five 
general names of things may, together with those formed by 
their composition, suffice, and have not you yourself, in mar- 
shalling ideas, been willing to grant them as the predicaments ? 
I have spoken above of substantial forms.^ And I know not 
whether we have sufficient reason for rejecting the vegetative 
souls,'^ since persons of much experience and judgment recog- 

1 The aerial or ethereal vehicles are the aerial or celestial bodies of the 
spirits, which, according to More, the souls of men after sufiieient purification 
attain, either at death, in the case of a very few of the noblest and most 
heroic, or at some period after death. Cf. H. More, Opera omnia, Loudini, 
l()7!t, 2 vols., fol. ; Tract, de irnmortaliiate animie, Bk. III. chap. 1, Axioma, 27, 
§§ 3, 28 sq.. Vol. 2, p. 396 sq., chap. 11, § 2, p. 427; Antidotus adversus Atheis- 
mum, Bk. III. chap. 3, § 9, Vol. 2, p. 99. — Tk. 

2 Cf. ante, p. 349 and note. — Tr. 

3 The scholastic philosophy recognized three forms or kinds of souls, corre- 
sponding to the three orders of life, plants, animals, and men, viz.: the rege- 
tative, sensitive, and intellective (anima vegetahilis or nutritiva, sensibilis or 
sen.ntiva, intellectiva or rutionalis). Of these the vegetative is the lowest, 
the sensitive the next higher, the intellective the highest ; and the higher 
form includes potentially in itself the lower and subordinate form and its 
functions. The functions of the vegetative soul are nutrition, growth, repro- 
duction; of the sensitive soul, sensation, feeling, perceptional, appetitive and 
emotional activity; of the intellective, those of the reason and the \\ill. In 
man, these several functions are all united in the intellective or rational soul, 
which he alone possesses, and which comjirises witliin itself the sensitive and 
vegetative souls. Cf. Stiickl, Gesch. d. Philos. d. Mittelalters, 11. 2 [Vol. 31. 
592 sq., CIS sq., 633 sq. — Tr. 



cii. x] ON HUMAN UNDERSTANDING 381 

nize a great analogy between plants and animals, and you, sir, 
have appeared to admit animal sonls. Abhorrence of a vacuum 
may be soundly understood; i.e. supposing nature has once 
filled space, and that bodies are impenetrable and non-condens- 
able, she could not admit any vacuum ; and I consider these 
three suppositions well grounded. But the intentional species,^ 
which are to make the connection between the soul and the 
body, are not so, though we may excuse the sensible species,^ 

1 Cf. 5th letter of Leibnitz to Clarke, § 84, Gerliardt, 7, 410, Ei-dmaim, 773, 
b, Jacques, 2, 4(;5, Dutens, 2, Pt. I, IGl, trans. Duncan, 275. 

The doctrine of the intentional species {species intentionales) to which 
were ojiposed tlie real species {species reales) or the actual forms of things, 
arose in the attempts of the Mediseval Sclioolmen to explain the process and 
philosophy of sense-perception and cognition. Two views have in general been 
held concerning their nature: 1. That they were the forms, similitudes, or 
images {fornix, similitudines, simulacra) of external objects, different both 
from the mind and from these objects, the intermediate and vicarious repre- 
sentatives of these objects in perception and thought, the media through 
which the mind infei-s and comes to know these external objects — a form of 
the doctrine of mediate perception. 2. That they were modifications of the 
mind itself, occasioned by the action upon the mind of the external object and 
the mind's responsive reaction thereto, by which the mind is likened or con- 
formed to the given object and so detei-mined immediately to cognize it. 
The latter view is maintained by the Roman Catholic psychologists, as being 
the doctrine of the greatest of the schoolmen, such as All)ertus Magnus, 
Thomas Aquinas, Duns Scotus, and as giving the real meaning of the terms 
they use. It is the more correct interpretation. 

The intentional species, according as they affected or were modifications of 
the sense or the intellect, were divided into sensible species {species sensihiles) 
and intelliylble or intellectual species {.species intelligihiles vel intellectuales) . 
Both the sensible and the intelligible species were further distinguished as 
impressed species {species ijnpressa) and expressed species {species expressa). 
According to the representative theory of the intentional species, the species 
impressa was the vicarious existence emitted by the object, impressed on the 
particular faculty, and concurring with it in its operation ; while the species 
expressa was the actual operation elicited by the faculty and the impressed 
species conjointly, i.e. the sensations and intellections. The direct or imme- 
diate theory regarded the genesis of species, whether as sensible or intelligible, 
as exhibiting two stages : 1. In sensuous cognition, (a) the species sensibilis 
impressa, or "the modification of the sensuous faculty viewed as au impres- 
sion wrought in the mind by the action of the object," and (h) the sf)ccies 
sensibilis expressa, or "the reaction of the mind as an act of cognitive con- 
sciousness." 2. In intellectual cognition, (a) the species intelligibilis im- 
pressa, or the "modification effected in the recipient capacity" of the 
iiitellectus pattens vel possibilis (the ^^assine intellect — Aristotle's vov^ rraerjn- 
Ko?), and (b) the species intelligibilis expressa, or the "mental modification 
reflecting the essence of the object, and by means of wliich the object is ap- 
prehended," a modification due to the act of the intellectus agens (the active 
intellect — Aristotle's roO? ttoujtikos). 



382 LEIBNITZ'S CRITIQUE OF LOCKE [bk. hi 

which proceed from the object to the distant organ, meaning 
thereby the propagation of motion. I admit that there is no 
Phitonic soul of the 7vorld, for God is beyond the worhl, extixi- 
mundana intelligentia, or rather supramundana} I know not 
whether by the tendency to movement of the Epicurean atoms 
you understand the weight attributed to them, no doubt with 
reason, since they maintain that bodies all move of them- 
selves in one and the same direction. The late Henry More, a 
theologian of the English Church, Avholly clever as he was, 
showed himself a little too ready to invent hypotheses which 
were neither intelligible nor apparent ; witness his HyJarchic 
principle ^ of matter, a cause of weight, elasticity, and other 
wonders which are met with. I have nothing to say of these 
ethereal vehicles, having never examined their nature. 

§ 15. Ph. An example touching the word matter will assist 
you the better to enter into my thought. Matter is taken as 



The doctrine of the intentional s^jecies was held hy the Realists, Aquinas, 
Duns Seotus, and others. The Nominalists, especially Duraudus, Biel, and 
Occam, rejected it, and the doctrine was exploded in the seventeenth century, 
largely hy the ar£;uments of Gassendi, Hobbes, and Descartes. On the whole 
subject, cf. Hamilton's Eeid, 8th ed., Edinburgh, 1880, Vol. 1, p. 267 sq., and 
Note M., Vol. 2, p. 951 sq.; Lects. on Metnphys., Boston, 1875, p. 291 sq., and 
notes; Stockl, Gcsch. d. Philos. d. Mittelalters, II. 1 [Vol. 2] 46.3 «$., II. 2 
[Vol. .3] 808, c)65, 978, 991 sq., III. [Vol. 4] 634 sq.; Haureau, Histoire de la 
philos. sc-olastique, II. 1 [Vol. 2] 417 .^q., II. 2 [Vol. 3] ^47 sq., ,378 sq. ; Prantl, 
Gesch. d. Logik im Ahendlande, Vol. 3, pp. 113, 210 sq., 294, 335 sq. ; Maher, 
S. J., PsycJiolo()y (Manuals of Catholic Philosophy — Stonyhurst Series), pp. 
49-53, 290-297, London: Longmans, Green & Co., 1890; Zigliara, Siimma 
Philoso2)hica, 3d ed., Lugduni, 1880, Vol. 2, pp. 243-4, 260 sq. ; Suarez, De 
Anima, Lib. III. cc. 2, 3; Kleutgen, Philos. d. Vorzeit, §§ 18-52; Sanseverino, 
DynamHofiia, Neapoli, 1802-66, Vol. 1, pp. 373-403 (of which pp. .390-400 
contain " an effective refutation of the charge of representationism against 
St. Thomas and the leading scholastics, based on the doctrine of species"). 
Vol. 2, pp. 5msq. — T-R. 

1 Cf. Theodicee, Pt. II. § 217, Gerhardt, 0, 248, Erdmann, 571, a, Jacques, 2, 
205. — Tr. 

2 Cf. Gerhardt, Leibniz, philos. Schrift., 7, 339 ; letter to Placcius, Sept. 8, 
1690, Diitens, Lelbnit. op. om., 6, 48; to T. Burnett, Aug. 24 (v.s.) 1697, G. 3, 
217, D. (;, 26.3. More rejected the mechanical explanation of physical nature', 
and adopted the principium hylarchicum, or spiritas naturse as he designates 
it, the immaterial force in all nature, the principle of the movement and 
sympathy of beings, similar to the anima muyidi of the Platonists and tlie 
archasus {cf. ante, p. 67, note 3) of the Alchemists. Cf. H. More, Opera omnia, 
Londini, 1679, Enchiridion metaphys., especially in the Scholia, to chap. 13^ 
§ 4, Vol. 1, p. 222 sq. ; also Tract, de immortcditate animse, Bk. III. chap. 12, 
Vol. 2, p. 430.— Tk. 



CH. x] ON HUMAN UNDERSTANDING 383 



an entity really existing in nature, distinct from the body; 
which indeed is thoroughly self-evident ; otherwise these two 
ideas might be put indifferently the one in the place of the 
other. For we may say that one single matter composes all 
bodies, but not that a single body composes all matter. 
Neither will we say, I think, that one matter is greater than 
another. Matter expresses the substance and solidity of 
body ; thus we no more conceive different matters than differ- 
ent solidities. But since matter has been taken as a name of 
something existing under this determination, this thought has 
produced unintelligible discourse and confused discussion upon 
materia prima. 

Th. This example appears to me to serve rather to excuse 
than to blame the Peripatetic philosophy. If all silver were 
figured, or rather because all silver is figured by nature or art, 
is it less allowable to say that silver is an entity really existing 
in nature, distinct (taking it in its precision) from the plate or 
the money ? You will not on that account say that silver is 
nothing else than certain qualities of money. Thus it is not 
so useless as you suppose to reason in general physics about 
materia pirima and to determine its nature in order to know 
whether it is always uniform, whether it has some other 
property besides impenetrability (as I in fact have shown ^ 
after Kepler that it also has what may be called inertia), etc., 
although it is never found wholly pure ; as it would be allow- 
able to reason about pure silver^ although we had none with us 
nor the means of purifying it. I do not at all disapprove 
what Aristotle has said about materia prima ; ^ but one cannot 

1 Cf. De ipsa natura, icm, § 11, Gerliardt, Leibniz. pMlos. Schrift., 4, 510, 
Erdmann, 157, a, Jacques, 1, 4(i2 (in French), Dutens, 2, Pt. II., 54, trans. 
Dnncan, 119; Theodicee, Pt. I., § 30, G. 0, 119, E. 512, a, J. 2, 89, Dutens, 1, 
141 (in Latin) ; Specimen dynamicum, 1(!95, Pt. I., Gerhardt, Leibniz, math. 
Schrift., (i, 234 nq., Dutens, 3, 315 sq., trans. Appendix, 670 sq. ; G. Leibniz, 
philo's. Schrift., 4, 4(14-7, Dutens. 2, Pt. I., 2:^4-7, two letters to the editor of the 
"Journal des Savans," in the numbers for June 18th, 1(!91, January, KHi, the 
first originally a fragment from a letter to Antonio Alberti, G. 7, 447-9; 5th 
letter to Clarke, § 102, G. 7, 414, E. 775, h, J. 2, 470, Dutens, 2, 165, trans. Duncan, 
280. In tlie letter to Jac. Thomasius, April 20-30, 1669 (cf. G. 1, 17, 18, 24), 
Leibnitz affirmed that matter consisted of extension and inpenctrability only. 
— Tr. 

2 Of. Zeller, Philos. d. Griech., 3d ed., 1879, II. 2 [Vol. 4] , p. 320, note 2 ; and 
Bonitz, Ltd. Ariat. sub voe. v^rj, in vol. 5 of Berlin Academy, cd. of Aristotle. 
Cf. also Gerhardt, Leibniz, philos. Schrift., 7, 259. — Tr. 



384 LKllLMTZ'S ClUTIQUE OF LOCKE [hk. in 

lii'lj) l)l;imins:r tlioso who liave stop})ed too soon and have con- 
jured \\\) cliinu'iMs out of the ill-understood words of this 
jihilosopher, who i)oi'lia})s also has given too much occasion 
souu'tinu's for this misconception and nonsense. But we 
should not exaggerate so much the defects of this celebrated 
author, because we know that many of his works were not 
completed or published by himself. 

§ 17. Fh. The Jjfih abnse is the putting of words in the place 
of things which they do not and cannot in any way signify. 
It occurs when by the names of substances we mean to say 
something more than this : what I call gold is malleable 
(although at bottom then gold signifies nothing else than what 
is malleable), intending to have it understood that mallea- 
bility depends upon the real essence of gold. Thus we say 
that it is right to define man with Aristotle as a reasonable 
animal ; and that it is not right to define him with Plato 
as a two-legged animal without feathers and with broad nails. 
§ 18. There is scarcely any one who does not suppose that 
these words signify a thing having a real essence upon which 
these properties depend; but it is a plain abuse when the 
complex idea signified by this word does not include this thing. 

T7i. For myself I should rather think that we are plainly 
wrong in censuring this common usage, since it is very true 
that in the complex idea of gold is included the thought that 
it is a thing having a real essence, whose constitution is un- 
known to us in detail otherwise than that upon it depend such 
qualities as malleability. But in order to express its mallea- 
bility without identity and without the defect of coccysm or 
repetition (see chap. 8, § 18),^ we must recognize this thing by 
other qualities, as color and weight. And it is as if we said 
that a certain fusible body, yellow and very heavy, called gold, 
has a natvire which gives it besides the quality of being very 
soft to the hammer and capable of being made very thin. As 
for the dejinition of man attributed to Plato, which he appears 
to have made only for practice, and which you would not, I 
think, compare seriously with that which is received, it is 
manifestly a little too external and provisional; for if this 
Cassoivary, of which you recently spoke (chap. 6, § 34), had 

1 The reference is incorrect. Perbaiis chap. (3, § 18, is meant, or chap. 10, 
§18. — Tr. 



cii. X] ON HUMAN UNDEllSTANDING 385 

been found, to have wide nails, it would be man ; for it would 
not have been necessary to strip it of its feathers, as in the 
case of the cock which Diogenes, as they say, wished to make 
a Platonic nian.^ 

§ 10. Ph. In the mixed modes, as soon as an idea entering 
therein is changed, you at once recognize it as another thing, 
as plainly appears in the words, mtirder, which signifies in 
English (as Mordt in German), homicide premeditated with 
design ; manslaughter (a word corresponding in origin to homi- 
cide), a voluntary but not premeditated homicide; chance- 
medley (a chance melee, according to the force of the word), 
homicide committed without design ; for what is expressed by 
the names and what I think to be in the thing (which I called 
before nomincd essence and real essence) is the same. But it is 
not so in the names of substances ; for if one puts into the idea 
of gold what another leaves out, for example fixedness and 
solubility in aqua regia, men do not think for that reason that 
its species has been changed, but only that the one has a more 
perfect idea than the other of what constitutes the real con- 
cealed essence to which the name of gold is given, although this 
secret relation is useless and serves only to involve us in diffi- 
culties. 

Th. I think I have already made this statement ; but I am 
going also to show you clearly here, that what you, sir, have 
just said, is found in the modes, as in the substances, and that 
we have no ground for censuring the internal essence for this 
relation. Here is an example: we may define a parabola, in 
the sense of the geometers, as a figure in which all the lines 
parallel to a certain straight line are united by thought in a 
certain point or focus. But it is rather the exterior and the 
effect which is expressed by this idea or definition, than the 
internal essence of this figure or what can at once make known 
its origin. We may at the beginning even doubt if such a 
figure as we wish and which ought to produce this effect is a 
possible thing; and it is this which with me shows whether a 

1 Of. Diogenes Laertius, c. 230-250, Be viAiK, dixjtnutihu.'i el (ipop/il.hcumatis 
clurtirum philoHOphoruni lib. dccnn, VI. 40: UAaTiovo? opto-a/iei-ov, 'Ai/OpwTros eo-rl 

fojoi' Sivovi', amepov, Kal eiSoKi/xoOi'To?, TiAas [AtoyeVTjt 6 /cuiof] a^eKTpvova ei(7))>'eyKfi' ei? 
Tr)!/ rrxo^rtu auToO, KaC (|)r)(TU', OuTo? irrriu !> UAaTioi'Oir drflpajTros. '69ev T<p opo) 7rpo<rtTi;0»j 

To TT\aTvuivvxoi'. The ilcjiniiions ascril)ed to Plato, and found in some editions 
of his works, are boyoiid donl)t si)uri()iis. — Tr. 
2 (' 



;lS(i LEIBNITZ'S ClUTIQUE OF LOCKE [hk. in 

ilelinition is ouly nominal and taken from the properties, or 
whether it is also real. But he who mentions the parabola 
anil knows it only by the definition I have just spoken of, 
ceases not, when speaking of it, to understand a figure which 
has a certain construction and constitution unknown to him, 
but wliich he wishes to learn in order to be able to draw it. 
Another who has examined it more thoroughly will add some 
other i)roperty, and will discover, for example, that in the 
figure asked for, the portion of the axis intercepted between 
the ordinate and the perpendicular drawn to the same point 
of the curve is always constant, and equal to the distance 
from the vertex to the focus. He will thus have a more per- 
fect idea than the former, and will come more easily to the 
drawing of the figure, although he is not yet there. And, 
moreover, Ave shall agree that it is the same figure, the consti- 
tution of which is still concealed. You see then, sir, that all 
that 3'ou have found and partly censured in the use of words 
signifying substances is also found and found plainly justified 
in the words signifying the mixed modes. But what has made 
you think that there was some difference between the sub- 
stances and the modes,^ is merely the fact that you have not 
consulted here the intellectual modes difficult of discussion, 
which are found to resemble in all this bodies which are still 
more difficult to know. 

§ 20. Ph. Thus I fear I must suppress Avhat I washed 
to say to you, sir, of the cause of what I have thought an 
abuse, as if it were because we falsely think that nature 
always acts wdth regularity and fixes limits to each species by 
this specific essence or internal constitution which we there 
understand and wdiich alw^ays follows the same specific name. 

Til. You see clearly then, sir, by the example of the geo- 
metrical modes, that w-e are not wrong in referring them to 
internal and specific essences, although there is great differ- 
ence between sensible things, whether substances, or modes, 
of which we have only nominal provisional definitions, and 
of which we do not readily hope for real ones, and between 
the intellectual modes, difficult of discussion since we can at 
last reach the internal constitution of the geometrical figures. 

1 Jacques reads : " c'est que vous n'avez point consulte'," etc. Gerhardt and 
Erdinanu read: "u'est que vous," etc. — Tr. 



til. x] ON HUMAN UNDEESTANDING 387 

§ 21. Ph. [I see at last that I should have been wrong in 
laying the blame of this relation upon the essences and internal 
constitutions, under the pretext, that this would render our 
words signs of nothing or of an unknown something. For 
what is unknown in certain respects may make itself known 
in another way, and the inner nature may partly reveal itself 
by the phenomena which spring from it. And as for the 
question: whether a monstrous foetus is a man or not? I see 
that, if it cannot be decided at once, this fact does not prevent 
the species from being well fixed in itself, our ignorance 
nowise changing anything in the nature of things.] 

Th. In fact, some very clever geometers have chanced to 
possess insufficient knowledge as to what the figures were, 
many qualities of which seemingly exhaustive of the subject 
tliey knew. For example, there were some lines called 2'x'ctrls,^ 
of which there were given indeed the quadratures and the 
measure of their surfaces and of the solids made by their 
revolution, before it was known that they were only a com- 
position of certaiii cubic paraboloids. Thus in considering 
beforehand tliese pearls as a particular species, they had only 
provisional knowledge of them. If this may happen in geom- 
etry, do you wonder that it is difficult to determine the species 
of corporeal nature which are incomparably more complex ? 

§ 22. Ph. Let us pass to the sixth abuse in order to con- 
tiuue the enumeration begun, althougli I see clearly that some 
of the points must be struck from the list. This general but 
little noticed abuse is this : men having by long use attached 
certain ideas to certain words, imagine that this connection is 
manifest and that everybody agrees to it. Whence it comes 
that they feel very strange, when asked the meaning of the 
words they employ, when indeed the question is an absolutely 
necessary one. There are few people who do not take it as an 

1 Cf. Neio Essays, Bk. IV., chap. 7, § 4, Tli. infra, p. 465. Reud Fraufois 
Walter de Sluse, 1622-1G85, a Flemish geometer, canon of Liege cathedral, and 
author of the method for the construction of the roots of equations of the 3d 
and 4th degree, " which consists in reducing the resolution of the proposed 
equation to that of the system of two equations representing two conies, by 
introducing an unknown auxiliary whose elimination reproduces tlie primitive 
equation." He developed this method in his Mcsolahium ct prublemata solida, 
etc., 4to, Leodii Eburonum, KifiS. Leibnitz mentions tliis work in a letter to 
Hobbes, l.'i-22 Jvily, 1G70, Gerhardt, Leibniz, philus. tidirift., 7, 573. — Tr. 



.188 LEIBNITZ'S CRITIQUE OF LOCKE [isk. hi 

affront if asked what they mean Avhen speaking of life. But 
the vague idea they may have of it is insufficient when the 
question arises as to the knowledge wliether a plant, already 
formed in the seed, or a pullet in the e^^^ not yet in process 
of incubation, or a man in a swoon without sense or motion, 
has life. And although men do not wish to appear so little 
intelligent or so obtrusive as to find it necessary to ask for an 
explanation of the terms used, nor critics so disagreeable as to 
censure others unceasingly for the use they make of words, 
nevertheless when it is a question of exact research, such 
explication is necessary. Often scholars of different parties 
in the reasonings they display the one against the other 
merely speak different languages and think the same thing, 
although perhaps their interests are different. 

Th. I think I have explained sufficiently my views upon 
the notion of life, which must always be accompanied by per- 
cejition in the soul ; otherwise it would be only an appearance, 
as the life which the American savages attributed to watches 
or clocks, or which those magistrates attributed to the mario- 
nettes, who believed them animated by demons, when they 
desired to punish as a sorcerer the one who had first pre- 
sented this spectacle in their city. 

§ 23. Ph. In conclusion, words serve (1) to make our 
thoughts understood, (2) to do this easily, and (3) to furnish 
entrance into the knowledge of things. Words fail at the 
first point, when they have no definite and constant idea 
either received or understood by others. § 23. They fail in 
facility, when they have very complex ideas, without distinct 
names ; this is often the fault of the languages themselves 
which have no names ; often also of the man who is ignorant 
of them ; in that case extensive paraphrases are necessary. 
§ 24. But when the ideas signified by the words do not agree 
with what is real, they fail in the third point. § 26. (1) He 
who has terms without ideas is like a man who has onlj' a 
catalogue of books. § 27. (2) He who has very complex ideas 
is like a man who has a quantity of books in loose sheets 
without titles, and who could not give the book save by giving 
the sheets in succession. § 28. (3) He who is not constant 
in the use of signs is like a merchant who sells different goods 
under the same name. § 29. (4) He who attaches particular 



I 



CH. x] ON HUMAN UNDERSTANDING 389 



ideas to received words cannot enlighten others by the light he 
may have. § 30. (5) He who has in his head ideas of sub- 
stances which never had existence, cannot advance in real 
knowledge. § 33. The first will speak in vain of the taran- 
tula or of charity. The second will see new animals without 
being able easily to show them to others. The third will 
take body sometimes as a solid, sometimes as a mere exten- 
sion ; and by frugality he will designate sometimes the virtue, 
sometimes the kindred vice. The fourth will call a mule 
by the name horse, and what everybody calls prodigal will be 
to him generous ; and the fifth will seek in Tartary on the 
authority of Herodotus ^ a nation composed of men having only 
one eye. I remark that the first four defects are common to 
the names of substances and modes, but that the last is pecu- 
liar to substances. 

Th. Your remarks are very instructive. I will only add 
tliat you seem to have something chimerical still in your ideas 
of the accidents or forms of being ; and so the fifth defect is 
also common to substances and to accidents. The extravagant 
shepherd was not so, only because he believed there were 
nymphs concealed in the trees, but also because he always 
expected romantic adventures. 

§ 34. Ph. I had thought to conclude, but I remember the 
seventh and last abuse, which is that of figurative terms or 
allusions. But there will be difliculty in thinking it an abuse, 
because what is called wit and imagination is better received 
than truth wholly dry. It goes well in discourse where you 
only seek to please; but at bottom, order and clearness ex- 
cepted, all the art of rhetoric, all these artificial and figura- 
tive applications of words, serve only to insinuate false ideas, 
to excite the passions and seduce the judgment, so that they 
are nothing but pure frauds. Nevertheless this fallacious art 
is given the first rank and rewards. It is evident that men 
care but little for truth and much prefer to deceive and to be 
deceived. This is so true that I doubt not that what I have 
just said against this art is regarded as the result of an extreme 
audacity. For eloquence, like the fair sex, has charms too 
powerful to alloAv itself to be opposed. 

1 Bonk III., clmp. llfi; IV . <'liai)S. i:!, 27 : rf. nlsn .Escliylus, rronicllivua, 823 
(SOI, Diudorl), lid ed., F. A. Palcy, Loiidoii, 1870; Paiisiuiius, 1, 24, 0. — Tb. 



S90 LEIBNITZ'S CRITIQUE OF LOCKE [hk. in 

Th. Very far from censuring your zeal for the truth, I 
linil it just. And would that it might be effective. I do 
not wholly despair of it, because you seem to me, sir, to combat 
eloquence with its own weapons, and to have an eloquence of 
anotlier species superior to this deceptive kind, as there was a 
Venus Urania, mother of divine love, before whom this other 
bastard Venus, mother of a blind love, dared not appear with 
her child with eyes blinded.^ But that indeed proves that 
your thesis needs some moderation, and that certain adorn- 
ments of eloquence are like the Egyptian vases which you 
could use in the worship of the true God. It is as in painting 
and music, which are abused, one of which often represents 
grotesque and even hurtful imaginations, and the other softens 
the heart, and the two amuse in vain ; but they can be usefully 
employed, the one to render the truth clear, the other to make 
it effective, and this last result must be also that of poetry 
which contains rhetoric and music. 



CHAPTER XI 

OF THE REMEDIES WHICH MAY BE APPLIED TO THE IMPER- 
FECTIONS AND ABUSES JUST SPOKEN OF 

§ 1. Ph. This is not the place to plunge into this discussion 
upon the use of a true eloquence, and still less to reply to your 
obliging compliment, since we ought to think of bringing this 
matter of ivords to an end, by seeking the remedies for the 
imperfections we have noticed therein. § 2. It would be ridic- 
ulous to attempt to reform the languages, and to desire to com- 
pel men to speak only according to the measure of their knowl- 
edge. § 3. But it is not too much to desire that philosophers 
speak exactly, when the question concerns a serious search for 
the truth : without this all will be full of error, opiniativeness, 
and vain disputes. § 8. The Jirst remechi is to use no word 

1 For the myth here referred to liy Leibnitz, ef. Plato, Symposium, 180. D, 
Jowctt's trans". Vol. 2, p. 32, 2(1 ed., 1875, Vol. 1, p. .550, .Sd ed., 1802; Pausa- 
nias, 9, 1(!, ."; also Harrison- Verrall, Mytholoc/y cmd Monuvients of Ancipvt 
Atliiiis, 212 sq., London, Macmillan & Co., 1890; VtaWev, Griech. Mythol.,2d 
ed., 18G0, Vol. 1, p. 265. — Tr. 



CH. XI] ON HUMAN UNDERSTANDING 391 

without attaching thereto an idea, instead of frequently em- 
ploying words like instinct, sympathy, antipathy, without 
attaching any sense to them. 

Th. The rule is good ; but I know not whether the examples 
are pertinent. Everybody seems to understand by instinct an 
inclination of an animal to what is proper for it, without on 
that account apprehending its reason ; and men indeed ought 
less to neglect these instincts, which they discover moreover 
in themselves, although their artificial method of living has 
for the most part nearly effaced them ; the physician of his 
own accord, indeed, has carefully observed it. SymjMthy or 
antipathy signifies that which in bodies destitute of feeling 
corresponds to the instinct for luiion or separation found in 
animals. And although we have no such knowledge of the 
cause of these inclinations or tendencies, as is to be desired, 
we nevertheless have a notion of them suflicient to discourse of 
them intelligibly. 

§ 9. Ph. The second remedy is that the ideas of the names 
of the modes at least be determined and, § 10. that the ideas 
of the names of substances be more conformed to what exists. 
If any one says that justice is conduct conformed to the law 
relating to the good of another, this idea is not sufficiently 
determined, so long as we have no distinct idea of that which 
is called laiv. 

Th. We might say here that the laio is a precept of wisdom 
or of the science of happiness. 

§ 11. Ph. The third remedy is to employ terms so far as 
possible in conformity with received usage. § 12. The fourth 
is to declare in what sense we take the words, whether we 
coin new ones or employ the old in a new sense, (or) 
whether we find that use has not sufficiently fixed their mean- 
ing. § 13. But there is some difference. § 14. The words for 
simple ideas which cannot be defined, are explained by synony- 
mous words, when they are better known, or by showing the 
thing. It is by these means that we can make a peasant un- 
derstand what the color feuille morte is, by telling him that it is 
that of dry leaves which fall in the autumn. § 15. The names 
of the mixed modes should be exi)laine(l by definition, for that is 
possible. § 16. It is upon this ground that ethics is suscepti- 
ble of demonstration. We shall take man as a corporeal 



S<I2 



LHlliNirZ'S CRITIQUE OF LOCKE [nic. in 



rational being without troubling ourselves about his external 
fif^urc, § 17. for it is by means of definitions that the matters 
of morality may be clearly treated. AVe shall rather define 
justice according to the idea we have in our mind than 
seek a model therefor outside of us, as Aristides, and form 
it thereupon. § 18. And as the majority of the mixed 
modes nowhere exist together, we can fix them in defining 
them only by the enumeration of that which is scattered. 
§ 19. In substances there are ordinarily some directing or 
characteristic qualities which we consider as the most distinc- 
tive idea of the species, to which we suppose the other ideas 
forming the complex idea of the species are attached. It is 
form in vegetables and animals, and color in animate bodies, 
and in some color and form together. This is why, § 20. the 
definition of man given by Plato is more characteristic than 
that of Aristotle ; or why we should not cause the death of 
monstrous productions, § 21. and often sight avails as much 
as any other test ; for persons accustomed to test gold often 
distinguish by sight the true from the false, the pure from 
that which has been adulterated. 

Th. Everything doubtless returns to the definitions which 
may extend even to primitive ideas. One and the same sub- 
ject may have several definitions, but the knowledge that they 
agree with themselves, must be learned by reason, by demon- 
strating one definition by another, or by experience, by jDroving 
that they constantly go together. As for morality, one part is 
wholly grounded in reason ; but there is another depending 
upon experience and related to the disposition. For a knowl- 
edge of substances, form and color, i.e. the visible, gives us 
the first ideas, because it is by these that we know things 
at a distance ; but they are ordinarily too provisional, and in 
things of importance to us we try to know substance more 
closely. I am astonished, moreover, that you return again to 
the definition of man, attributed to Plato, since j^ou have just 
yourself stated, § 16. that in morals man must be taken as a 
corporeal rational being without troubling ourselves about the 
external form. For the rest it is true that a large practice does 
much for discerning at sight what another may scarcely know 
through arduous experiments. And ph^^sicians of large experi- 
ence, with very good sight and memory, often know at the first 



CH. XI] ON HUMAN UNDERSTANDING 393 

appearance the disease wliich another will draw out for himself 
with difficulty by force of questioning and trying the pulse. 
But it is well to unite all the indications we may have. 

§ 22. Ph. I admit that he to whom a good assayer makes 
known all the qualities of gold, will have a better knowledge 
of them than sight could give. But if we could learn its in- 
ternal constitution, the meaning of the word gold would be as 
easily determined as that of the triangle. 

Til. It would be wholly as determined, and it would have in 
it no 2^^'ovisional element ; but it would not be so easily deter- 
mined. For I think a distinction a little prolix would be 
necessary in order to explain the contexture of gold, as is the 
case indeed in geometry with figures whose definition is long. 

§ 23. Ph. Spirits separated from bodies have doubtless 
knowledge more perfect than ours, although we have no notion 
of the manner in which they may acquire it. But they may 
have as clear ideas of the radical constitution of bodies, as we 
have of a triangle. 

Th. I have already remarked, sir, that I have reasons for 
thinking that no created spirits exist entirely separate from 
bodies ; but there are no doubt some whose organs and under- 
standing are incomparably more perfect than ours, and which 
surpass us in every kind of conception, as much and more than 
Mr. Frenicle,^ or that Swedish boy of whom I have spoken to 
you, surpassed the common run of men in tlie calculation of 
numbers, made by imagination. 

§ 24. Ph. We have already noticed that the definitions of 
substances which may serve in explaining names are imperfect 
in relation to the knowledge of things. For usually we put 

1 Cf. Gerhardt, Leibniz. j)hilos. Schrift., 4, 319. Bernard Frenicle de Bessy, 
c. 1G05-1G75, brother of the poet Nicolas Frenicle, 1600-1661, "conseiller a la 
cour des monnaies," member of the Paris Academy of Sciences, who acquired 
the reputation of being the first arithmetician of his age by the rapidity with 
which he solved the most complicated numerical problems, and by his ingen- 
ious researches upon the solution in whole numbers of indeterminate equations. 
His metliod, known as tlie method of exclusions, apjiears to have been an inge- 
nious groping, l)ut based on some general propcisitions which greatly restricted 
this groping, and which have since been rigorously demonstrated by Leonard 
Euler, 1707-178?. and Jos. Louis Lagrange, 1736-1813. Pierre dc Fermat, KiOl- 
16(>.'), and Descartes. 1.596-1650, greatly admired his work, astonished tliat lie 
could go so far witliout the aid of algebra and tliat his arithmetic could con- 
duct him where analysis finds so much difficulty in going. His principal work 
was, Traite des tricmr/les, reeianyleH ea noinhre, Paris, 1676. — Tu. 



;?94 LEIBNITZ'S CKITIQl'l': OF LOCKE [hk. hi 

the name in the place of the thing ; then the name says more " 
than the definitions ; thus to give a good definition of sub- 
stances, we must study natural history. 

Th. You see then, sir, that the name gold, for example, 
signifies not only that which he who pronounces it knows of 
it^ — for example, something yellow, very heavy, — but also 
what he does not know, and which another ma}^ know, i.e. a 
body endowed with an internal constitution from which pro- 
ceed color and weight, and from which spring still other prop- 
erties admitted to be better known by experts. 

§ 25. Ph. It were now to be wished that those practised in 
physical researches would set down the simple ideas in which 
they observe that the individuals of each species constantly 
agree. But the composition of a dictionary of this kind 
which would contain, so to speak, a natural history, would re- 
quire too many persons, too much time, trouble, and sagacity 
for such a work ever to be hoped for. It would be well, how- 
ever, to accompany words with small copper-plate engravings 
of things knoAvn by their external form. Such a dictionary 
would be of much service to posterity and would spare future 
critics much trouble. Small figures as of the celery-plant 
(apium), of a Bouquetin {ibex, a kind of wild goat), would be 
more valuable than long descrii^tions of this plant or of this 
animal. And in order to know what the Latins called sfrigiles 
and sistriivi, tunica and paZZl^<7>^, figures in the margin would be 
incomparably more vah^able than the pretended synonymes, 
currycomb, cymbal, dress, cloak, mantle, which show but little 
of them. For the rest I shall not stop upon the seventh remedy 
of the abuse of words which is to employ constantly the same 
term in the same sense, or to give notice when you change it. i 
For we have spoken sufficiently of this subject. I 

TJi. Rev. Father Grimaldi,^ President of the ^Mathematical 

1 Claudius Philiji Grimaldi, with whom Leihuitz hecame acquainted durinir 
his stay in Rome in 1689, and with whom he corresponded, receiving from him 
after his return to Pelvin much interesting information. Cf. Guhrauer, G. W. 
Freiherr v. Leibniz, 2, 95 sq. ; Kuno Fischer, Gesch. d. ??. Philos., Vol. 2, p. 201, 
.3d ed., Heidelberg, 1889; Dutens, Leibniz, op. o?»., 4, Pt. L 81, 88 S(?., 88; 6, 
106, 128, 227, Gerhardt, Leibniz. phiIo.<i. Schrifi. 3, 166, 174. Schaarschmidt 
states that such dictionaries as Leibnitz here mentions on the authority of 
Grimaldi exist in fact among the Chinese, and have been brought to Europe, 
that the Bonn University library possesses a couple of parts of one such 
dictionary, and that it must be regarded as an alphabetically arranged orbis 
pictus. — Tr. 



CH. XI] ON HUMAN UNDERSTANDING 395 

Society at Pekiii, tells me that the Chinese have illustrated 
dictionaries. There is a small nomenclator printed at Nurem- 
berg in which there are such figures for each word which are 
good enough. Such an illustrated universal dictionary were to 
be desired, and would not be very difficult to make. As for the 
descrijytion of sjjecies, it is properly natural history, and we 
are working at it by degrees. Were it not for the wars 
(which have troubled Europe since the first foundation of the 
Societies or Royal Academies) it would be farther advanced, 
and already in a condition to profit from our labors ; but the 
great for the most part do -not recognize its importance, nor 
what good they deprive themselves of by neglecting the ad- 
vancement of solid knowledge ; and besides they are ordinarily 
too much indisposed by the pleasures of peace or by the cares 
of war to weigh things which do not strike them at once. 



I 



ESSAY ON UNDERSTANDING 

Book IV. — Of Knowledge 
CHAPTER I 

OF KNOWLEDGE IN GENERAL 

§ 1. Ph. Hitherto we have spoken of ideas and of tcords 
which represent them ; let us come now to the knoivledge, 
which the ideas furnish, for it rests only upon our ideas. 
§ 2. Knowledge is simply the perception of the connection 
and agreement, or of the opposition and disagreement, which 
we find between two of our ideas. Whether we imagine, con- 
jecture, or believe, it is always that. We perceive, for exam- 
ple, by this means, that white is not black, and that the 
angles of a triangle and their equality to two right angles 
have a necessary connection. 

Th. Knowledge has a still more general signification, so 
that we find it also in ideas or terms, before we reach proposi- 
tions or truths. And it may be said that he who has atten- 
tively looked at more pictures of plants and animals, more 
diagrams of machines, more descriptions or representations of 
houses or fortresses, who has read more ingenious romances, 
heard more curious narratives, this one, I say, will have more 
knowledge than another, even though there should not be a 
word of truth in all that which was ])ortrayed or related to 
him ; for the custom he has of representing in his mind many 
express and actual conceptions or ideas, renders him more fit 
to conceive what is placed before him ; and it is certain that 
he will be better instructed and more capable than anotlier 
who has neither seen nor read nor heard anything, ])rovided 

397 



308 LHUiMTZ'S CiaiUilH OF LOCKE [i.ic 



that in these stones and representations he takes nothing as 
true which is not so and that these impressions do not prevent 
him elsewhere from distinguishing the real from the imagi- 
nary, or the existent from the possible. This is why certain 
logicians of the period of the Reformation who Avere in some 
measure of the party of the Eamists/ were not wrong in say- 
ing that the tojncs or orders of invention (argumenta, as they 
call them) serve as much for the explication or very detailed 
description of an incomplex theme, i.e. of a thing or idea, as 
for the proof of a complex theme, i.e. of a thesis, proposition, or 
truth. And indeed a thesis may be explained, in order that 
its sense and force may be well known, without raising the 
question of its truth or proof, as is seen in sermons and homi- 
lies explaining certain passages of Holy Scripture, or in 
instruction or lectures upon certain texts of civil or canon law 
whose truth is presupposed. We can even say that there are 
some themes which are means between an idea and a proposi- 
tion. These are the questions, some of which demand only yes 
or no ; and they are the nearest to propositions. But there 
are some also which demand the how, the circumstances, etc., 
where there is more to be supplied in order to make proposi- 
tions. It is true, it may be said, that in descriptions' (even of 
things purely ideal) there is a tacit affirmation of possibility. 
But it is also true that, as we may undertake the explanation 
and proof of a falsehood, a method which sometimes serves as 
its best refutation, the art of description may fall upon the 
impossible also. Something like this is found in the novelle 
of the Count of Scandiauo followed by Ariosto,' and in the 

1 The Ramists were disciples of Peter Eamns (o/. infra p. 408, note 1). 
Schaarsfhmidt states that Leibnitz probably has in mind chiefly J. H. Alsted, 
whom he has previously (cf. ante. pp. .311, note 2, .3(52) cited, and whom he 
jireatly prized and studied, in whose Syatema lof/icm harmonicum, Her- 
borniae, 1614, p. 69, the arrpimentum is divided into arc/umentum simple/ 
fwhich Leibnitz calls theme inromplere) and into arc/umentum complexnm. 
The former, according to Alsted, is a "terminus extra omnem dispositionem 
dirigens materiam" (Leibnitz says: "uue chose ou idee"), the Mtter is a 
" definitio et distributio " (Leibnitz says : " una these, proposition ou verite ") . 
Cf. Alsted, p. 261.— Tr. 

2 I.e. in the sense of nominal definitions, which allow the really impossible. 
Cf. ante, p. 317, note 3. — Tr. 

3 Leibnitz here refers to Matteo Maria Boiardo, c. 1434-1494, Count of 
Scandiano, and the author of Orlando Innamorato. which a recent writer 
calls "the most chivalrous poem of the Renaissance," and "a masterpiece of 



CH. I] ON HUMAN UNDERSTANDING 399 



"Amadis of Ganl"^ or other old romances, in the fairy-stories 
which were again in fashion some years since, in the "True 
History"^ of Lucian and in the "Voyages" of Cyrano de 
Bergerac ; '^ to say nothing, of the grotesque figures of the 
painters. So we know stories with the rhetoricians belong in 
the number of progymnasmata or preliminary exercises. But 
taking knowledge in a narrower sense, i.e. as knowledo-e of 

inventive genius," and wiiieli furnished Ludovico Ariosto, 1474-15:53, with the 
theme of his Orlando Furioso. For an account of the two writers anil their 
i works, cf. J. A. Symonds, lieiialsnance in Italy, Pt. IV., Italian Literature, 
I Vol. 1, pp. 45(j sq., Vol. 2, pp. 1 sq. New York, H. Holt & Co., 1885. 

Through a misunderstanding of Leibnitz's reference to the Count of Scan- 
\< diano, Schaarschmidt, in his note to the passage, has wrongly identified him 
j with Tito Giovanni Ganzarini, 1518-1582, Professor of Literature at Modena, 
. called il Scandianese, from his birthplace, Scandiano. Ariosto published his 
Orlando Furioso in 151(), two years before Ganzarini was born, and could 
|; scarcely be said to have "followed " an author who was only fifteen years 
|;i old when the poet himself died. — Tr. 

I 1 The Arnadis de Gaiila, the best of all the old romances of chivalry, was 

j. originally written, it is supposed, about 13<)0, by Vasco de Lobeira, a Portu- 

\ guese knight attached to the court of John I. of Portugal, and who died in 1403. 

I The oldest text now extant is in Spanish prose, a version from the Portuguese 

' original, now lost, made by Garcia Ordonez de Montalvo, between 1492 and 

] 1504. Editions of the Spanish version are numerous, the earliest accessible 

I being that of 1519; and there are translations in English, French, German, 

' Italian, and other languages. The best and at present the only readable 

I edition in English is the abridged translation (with a Preface giving an 

: account, not, however, without error, of the work), made from the Spanish, 

by Robert Southey, London, 1803, 4 vols., 12mo, new ed., London, 1872, 3 vols., 

IGmo. Cf. also, V. de Lobeira, Amadis de Gaula, Barcelona, 1847-8, 4 vols., 

Wmo; George Tieknor, Hist, of Simnish Lit., 3d ed., Boston, 18()3, Vol. 1, 

pp. 198-207; L. Braunfels, Kritischer Versuch iiber Amadis, Leipzig, 1876. 

It may be added that the writer of the article, "Amadis of Gaul," in the 

Eneyclop. Brit., 9th ed., argues for the Anglo-Norman origin of the romance, 

on the ground that all its ideas and materials, its design and machinery, 

belong to the Anglo-Norman romance-cycle in vogue before Lobeira was 

born. — Tr. 

2 Tlie 'AATjeoCg i<TTopia.<; Aoyos ( Verm Historix) of Lucian is one of the witty 
satirist's cleverest works, written in easy and elegant Greek, and exhibiting 
great fertility of invention. It was purposely composed, says Lucian, as a 
satire on the poets and logographers who have written so many marvellous 
tales, and contains things which neither he nor any one else has ever seen, 
wliicli not only do not, but cannot, exist, and descriptions of experiences and 
adventures which are absurd and impossible, chief among which is a voyage 
to the moon. Lucian himself says that the only true statement in his History 
is that it contains notliing but lies from beginning to end. It has without doulit 
su))pli(!d hints to, or served as a model for, writers like Rabelais, Swiit, and 
Cyrano de Bergerac. — Tr. 

^ Cf. ante, p. 228, note 2. Amid many imaginative extravagances, these 
Voyuf/es contain a pretty exact knowledge of the philosophy of Descartes. — Tu. 



•100 l.i:ii5MTZ'S ('KiriQUE OF LOCKE [hk. iv 

truth, as you, sir, do licre, I say it is quite true that truth is 
always grounded in the agreement oi- disagreement of ideas, 
but it is not true in general that our knowledge of truth is a 
lH'ree[)tion of this agreement or disagreement. For when we 
kiu)W truth only I'luiiirically, from having experienced it, 
without knowing the connection of things and the reason 
there is in wliat we have experienced, we have no perception 
of this agreement or disagreement, unless we mean that we 
feel it in a confused way without being conscious of it. But 
your examples, it seems, show that you always demand a knowl- 
edge in which one is conscious of connection or opposition, 
and this is what cannot be granted you. Fiirther, we can 
treat a complex theme not alone by seeking the proofs of its 
truth, but also in explicating and otherwise illustrating it, 
according to the topical order, as I have already observed. 
Finally, I have a further remark to make upon our definition : 
viz. that it appears only suited to categorical truths, in which 
there are tivo ideas, the subject and the predicate ; but there 
is besides a knowledge of hypothetical truths or what may be 
reduced thereto (as disjunctives and others) in which there is 
connection between the antecedent and the consequent propo- 
sition ; thus more than two ideas may enter therein. 

§ 3. Ph. [Let us limit ourselves here to the knowledge of 
truth and then apply what will be said of the connection of 
ideas to the connection of propositions, in order to include in 
one whole the categorical and hypothetical truths.] Now I 
believe that this agreement or disagreement may be reduced