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Extension Co. j
IN ARCADIA
By Nicholas Poussin, 1594-1665,
NICHOLAS POUSSIN was born at Les Andelys in June, 1594. He early
showed ability enough at art to attract the attention of Quentin Varin.
Later he studied under Ferdinand Elle at Paris. The Chevalier Marini
employed him on illustrations for his poems and assisted him to reach Rome (1624).
There Marini died and Poussin was for a time in great distress.
His excellence soon found him patrons. In 1640 he returned to France and
was made a court painter by Louis XIII. He went to Rome once more in 1643
and died there in November, 1665.
He was the first great French painter. His style is quite classical in outline
and he has had much influence on landscape painting
"In Arcadia" pictures a group of peasants who are for the moment subdued
by reading on a tomb, 'He, too, lived in Arcadia."
The Library of
Original Sources
The Ideas that have influenced civiliza-
tion, in the original documents — translated
University Edition
Edited by
Dr. Oliver J. Thatcher
formerly head of the History
Department, University of Chicago
Assisted by more than One Hundred
European and American Scholars.
University Research Extension Co.
Milwaukee :: Wisconsin
EDITOR'S ACKNOWLEDGMENT
ALTHOUGH THE EDITOR only is responsible for the matter
included in this set of books, yet he has been greatly assisted by the
suggestions he has received from specialists in their own fields. As
the editing of the last volumes is not yet finished, it is impossible to
give full credit for such advice, but the editor takes this opportunity
to acknowledge the important counsel or additional suggestions
received from :
A. H. SAYCB, LL. D., D. D.,
PROFESSOR OP ASSYHIOLOGY, QUBBN'S COLLEGE, OXFORD UNIVERSITY.
CRAWFORD H. TOY, A. M., LL. D.,
PROFESSOR OF ORIENTAL LANGUAGES, HARVARD UNIVERSITY.
WALTER MILLER, A. M.r
PROFESSOR OF CLASSICAL PHILOLOGY,
THE LELAND STANFORD JUNIOR UNIVERSITY
HENRY RUSHTON PAIRCLOUGH, PH. D,,
PROFESSOR OF CLASSICAL LITERATURE,
THE LELAND STANFORD JUNIOR UNIVERSITY.
PRANK FROST ABBOTT, PH. D.,
PROFESSOR OF LATIN, UNIVERSITY OF CHICAGO.
JOHN CAREW ROLFE, PH. D.,
PROFESSOR OF LATIN, UNIVERSITY OF MICHIGAN.
DANA C. MONRO, A. M.,
DEPARTMENT OF HISTORY, UNIVERSITY OF PENNSYLVANIA.
EDWARD G. BOURNE, PH. D.,
PROFESSOR OF HISTORY, YALE UNIVERSITY.
FERDINAND SCHWILL, PH. D.,
DEPARTMENT OF MODERN HISTORY, UNIVERSITY OF CHICAGO.
HARRY BURNS HUTCHINS, LL. D.,
DEAN OF THE DEPARTMENT OF LAW, UNIVERSITY OF MICHIGAN.
WILLIAM H. WELCH, M. D., LL. D.,
DEAN OF THE MEDICAL FACULTY, JOHNS HOPKINS UNIVERSITY.
THEODORE WILLIAM RICHARDS, PH. D.,
DEPARTMENT OF CHEMISTRY, HARVARD UNIVERSITY.
PAUL REINSCH, PH. D.,
DEPARTMENT OF POLITICAL SCIENCE, UNIVERSITY OF WISCONSIN.
H. H. MANCHESTER, A. B.t
MANAGING EDITOR FOR THE ROBERTS-MANCHESTER PUBLISHING CO
ILLUSTRATIONS
VOLUME VI.
PAGE
IN ARCADIA (PoussiN 1594-1665) Frontispiece
SACRED AND PROFANE LOVE (TITIAN 1477-1576) 5
FLORA (TITIAN 1477-1576) 23
THE ADORATION OF THE SHEPHERDS (CORREGGIO 1494-1534) 38
NEWTON 124
THE LAST JUDGMENT (MICHAEL ANGELO 1475-1564) 155
LAVOISIER 297
LAPLACE 349
TABLE OF CONTENTS
VOLUME VI
PAGB
THE BEGINNING OF MODERN MEDICINE 5
HARVEY 6
On the Motion of the Heart Blood in Animals 7
EDUCATION 23
COMENIUS 25
Educational Ideas 25
THE BEGINNING OF MODERN PHILOSOPHY 38
DESCARTES 41
Meditations 42
SPINOZA 63
The Etb'cs, Part I 64
LEIBNITZ 78
The Monadology 79
HOBBES 93
Of Man 94
LOCKE 101
Ideas 102
Ideas and Things 106
Substance 114
SEVENTEENTH CENTURY NATURAL SCIENCE 117
ANTHONY VON LEEUWENHOECK 119
Observations on Animalculae 119
NEWTON 123
The Diffusion of Light 124
The Theory of Gravitation 135
HUYGHENS 141
The Wave Theory of Light 142
PAGB
THE BEGINNING OF CHEMISTRY 150
BOYLE 152
The Discovery of His Law 152
SEVENTEENTH CENTURY POLITICAL ECONOMY 155
THOMAS MUN 157
The Mercantile Theory 157
JOHN LOCKE 164
The Basis of Property is Labor 164
EIGHTEENTH CENTURY PHILOSOPHY 172
BERKELEY 172
Principles of Human Knowledge 173
HUME 185
Against the Principle of Cause and Effect 185
Against Personal Identity 189
KANT 201
The Prolegomena 203
The Critique of Pure Reason 207
EIGHTEENTH CENTURY SCIENCE 240
BOERHAAVE 242
Physiological Conceptions 242
LINNAEUS 247.
A Dissertation on the Sexes of Plants 248
FRANKLIN 261
Letter to Peter Collinson on Electricity 262
The Identity of Lightning and Electricity. The Lightning
Rod 266
The Kite Experiment 270
BLACK 272
The Discovery of Carbonic Acid Gas, "Fixed Air" 272
PRIESTLEY 278
The Discovery of Oxygen 279
SCHEELE 284
Chemical Treatise on Air and Fire 284
CAVENDISH 290
The Combination of Hydrogen and Oxygen into Water 291
PAGE
LAVOISIER 297
The Permanence of Matter 298
The Nature of Combustion 300
Respiration a Combustion 304
JAMES WATT 305
Invention of the Steam Engine 305
HUTTON 312
Theory of the Phenomena Common to Stratified and
Unstratified Bodies 313
HERSCHEL 335
The Discovery of Uranus 335
On Nebulous Stars 337
On the Proper Motion of the Sun and Solar System 347
LAPLACE 349
The Nebular Hypothesis 350
VOLTA 358
New Galvanic Instrument 359
RELIGIOUS MOVEMENTS 362
JOHN WESLEY 362
The Early Methodists 363
General Rules of the Society 365
The Doctrine of Justification 367
VOLTAIRE 377
On Toleration 378
EIGHTEENTH CENTURY POLITICAL ECONOMY 392
QUESNAY 392
General Maxims 393
ADAM SMITH 399
On the Principle of the Commercial or Mercantile System 399
Of Restraints upon Importation 409
THE BEGINNING OF MODERN MEDICINE
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a number of minor f* thr anatomy
great work was to brinj,- r> : :o ?-v? thin?;-*
We now come to thf ^t«-covt-ry of the
and the beginning of physioiogy . The Galr
of the heart and blood was that the bk»o<
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•irculation of the blood
ic doctrine of the action
in the left ventricle of
SACRED AND PROFANE LOVE
By Titian, 7^77-7576.
VECELLIO TIZIANO was born in Italy in 1477. When ten years old he was
sent to Rome. Here he studied under the Bellinis and Giorgione. On the
death of Giovanni Bellini, he completed the work unfinished in the hall of
the ducal palace at Venice.
In 1517 at Ferrara he painted his fine "Bacchus and Ariadne" and "The
Bacchanal." His portraits also became famous, and he made many trips to do
work for princely patrons.
Among his most famous paintings are the "Tribute Money" at Dresden, the
"Sacred and Profane Love" in the Borghese gallery, Rome, and the "Assumption
of the Virgin" at Venice.
He is one of the world's greatest painters, and the great representative of the
Venetian school. As a colorist he was considered unequaled.
THE BEGINNING OF MODERN MEDICINE
THE FIRST ATTEMPTS made in Christian Europe to revive the
study of medicine sought to go back to the Greek and Roman school
represented by Hippocrates, Galen, and Celsus. Paracelsus (1490?
— 1541) was the first to hold himself independent of both the Graeco-
Roman and the Arabian schools. He was an astrologer and an
alchemist and sought to find a remedy whose "spirit" was opposed
to the "spirit" of the disease. Remedies were supposed to contain
the essences of the things from which they were drawn. His famil-
iarity with alchemy led him to introduce chemical remedies such as
laudanum and antimony.
About this time Vesalius (1536-1564) began his work of cor-
recting in many details the anatomical ideas of the ancients, and
led the leaders of the science to d*epend somewhat on personal dis-
section and observation instead of entirely on authority. It is said
that the heart of a Spanish noble, supposedly dead, seemed to pal-
pitate under his dissecting knife, and that this brought him before
the inquisition where he was at first condemned to death, but the
sentence afterward commuted to a pilgrimage to the Holy Land.
He was shipwrecked when returning, and died of starvation at
Zante. His "De Corporis Humani Fabrica" is the first comprehen-
sive study of anatomy in modern times. It adds to and corrects in
a number of minor points, the anatomy of the ancients, but his
great work was to bring men to see things for themselves.
We now come to the discovery of the circulation of the blood
and the beginning of physiology. The Galenic doctrine of the action
of the heart and blood was that the blood in the left ventricle of
6 THE BEGINNING OF MODERN MEDICINE
the heart ebbed and flowed along the arteries, the blood in the right
ventricle along the veins, and that part of the blood of the right side
of the heart found a mysterious passageway to the left side through
invisible pores of the wall of the heart (septum).
Servetus (1511 — 1553) guessed that there was some sort of cir-
culation through the lungs, but when he was burned at the stake by
Calvin, almost all copies of his book, the "Restitutio," were burned
with him.
Caesalpinus (1519—1603) also had some glimmering of the
truth, but it remained for Harvey to extend and prove the theory
and to show its important bearings.
HARVEY
WILLIAM HARVEY was born on the southern coast of England
in 1578. He took his degree at Cambridge in 1597, and spent most
of the following four years under Fabricus at Pisa. In 1602 he re-
turned to England, and began the practice of his profession. He
became physician to St. Bartholomew's hospital in 1609, and in
1615 developed in his lectures on anatomy his view of the circulation
of the blood. His ideas were based upon patient observation, the
process of thought by which he arrived at them he describes as
follows :
"I frequently and seriously bethought me, and long revolved
in my mind, what might be the quantity of blood which was trans-
mitted, in how short a time its passage might be effected and the
like; and not finding it possible that this could be supplied by the
juices of the ingested aliment without the veins on the one hand
being drained, and the arteries on the other hand becoming ruptured
through the excessive charge of blood, unless the blood should some-
how find its way from the arteries into the veins, and so return to
the right side of the heart ; I began to think whether there might not
be a motion, as it were, in a circle. Now this I afterwards found
to be true ; and I finally saw that the blood, forced by the action of
the left ventricle into the arteries, was distributed to the body at
large, and its several parts, in the same manner as it is sent through
THE BEGINNING OF MODERN MEDICINE 7
the lungs, impelled by the right ventricle into the pulmonary artery,
and that it then passed through the veins and along the vena cava,
and so round to the left ventricle in the manner already indicated, —
which motion we may be allowed to call circular."
The new theory accounted for so many facts, such as the pres-
ence of the valves in the heart discovered by Fabricus, the effects of
binding a vein or artery, etc., that it soon won acceptance. It
opened the way for a study of the uses of the blood in nutrition, for
its chemical properties, for the study of functions, and in fact for
modern physiology.
Harvey first published his Excercitatio in 1628. He became
physician to Charles I.; in 1646 retired into private life; and died
June 3, 1667.
AN ANATOMICAL DISQUISITION ON THE MOTION OF
THE HEARTBLOOD IN ANIMALS
OF THE MOTION, ACTION, AND OFFICE OF THE HEART
From all these and other observations of the like kind, I am
persuaded it will be found that the motion of the heart is as follows :
First of all, the auricle contracts, and in the course of its con-
traction throws the blood, (which it contains in ample quantity as
the head of the veins, the storehouse and cistern of the blood,) into
the ventricle, which being filled, the heart raises itself straightway,
makes all its fibres tense, contracts the ventricles, and performs a
beat, by which beat it immediately sends the blood supplied to it by
the auricle into the arteries; the right ventricle sending its charge
into the lungs by the vessel which is called vena arteriosa, but
which, in structure and function, and all things else, is an artery;
the left ventricle sending its charge into the aorta, and through this
by the arteries to the body at large.
These two motions, one of the ventricles, another of the
auricles, take place consecutively, but in such a manner that there is
a kind of harmony or rhythm preserved between them, the two con-
curring in suchwise that but one motion is apparent, especially in
the warmer blooded animals, in which the movements in question
are rapid. Nor is this for any other reason than it is a piece of
machinery, in which, though one wheel gives motion to another, yet
8 THE BEGINNING OF MODERN MEDICINE
all the wheels seem to move simultaneously; or as in that mechanical
contrivance which is adapted to firearms, where the trigger being
touched, down comes the flint, strikes against the steel, elicits a
spark, which, falling among the powder, it is ignited, upon which
the flame extends, enters the barrel, causes the explosion, propels
the ball, and the mark is attained — all of which incidents, by reason
of the celerity with which they happen, seem to take place in the
twinkling of an eye. So also in deglutition: by the elevation of
the root of the tongue, the compression of the mouth, the food or
drink is pushed into the fauces, the larynx is closed by its own
muscles, and the epiglottis, whilst the pharynx, raised and opened
by its muscles no otherwise than is a sac that is to be filled, is lifted
up, and its mouth dilated ; upon which, the mouthful being received,
it is forced downwards by the transverse muscles, and then carried
by the longitudinal ones. Yet all these motions, though executed
by different and distinct organs, are performed harmoniously, and in
such order that they seem to constitute but a single motion and act,
which we call deglutition.
Even so does it come to pass with the motions and action of the
heart, which constitute a kind of deglutition, a transfusion of the
blood from the veins to the arteries. And if any one, bearing these
things in mind, will carefully watch the motions of the heart in the
body of a living animal, he will perceive not only all the particulars
I have mentioned, viz., the heart becoming erect, and making one
continuous motion with its auricles; but farther, a certain obscure
undulation and lateral inclination in the direction of the axis of the
right ventricle, [the organ] twisting itself slightly in performing its
work. And indeed every one may see, when a horse drinks, that the
water is drawn in and transmitted to the stomach at each movement
of the throat, the motion being accompanied with a sound, and yield-
ing a pulse both to the ear and touch ; in the same way it is with the
motion of the heart, when there is the delivery of a quantity of
blood from the veins to the arteries, that a pulse takes place, and
can be heard within the chest.
The motion of the heart, then, is entirely of this description, and
the one action of the heart is the transmission of the blood and its
distribution, by means of arteries, to the very extremities of the
body ; so that the pulse which we feel in the arteries is nothing more
than the impulse of the blood derived from the heart.
THE BEGINNING OF MODERN MEDICINE 9
Whether or not the heart, besides propelling the blood, giving it
motion locally, and distributing it to the body, adds anything else
to it, — heat, spirit, perfection, — must be inquired into by and by, and
decided upon other grounds. So much may suffice at this time,
when it is shown that by the action of the heart the blood is trans-
fused through the ventricles from the veins to the arteries, and dis-
tributed by them to all parts of the body.
So much, indeed, is admitted by all [physiologists] both from
the structure of the heart and the arrangement and action of its
valves. But still they are like persons purblind or groping about
in the dark ; and then they give utterance to diverse, contradictory,
and incoherent sentiments, delivering many things upon conjecture,
as we have already had occasion to remark.
The grand cause of hesitation and error in this subject appears
to me to have been the intimate connection between the heart and
the lungs. When men saw both the vena arteriosa [or pulmonary
artery] and the arteriae [or pulmonary veins] losing themselves in
the lungs, of course it became a puzzle to them to know how or by
what means the right ventricle should distribute the blood to the
body, or the left draw it from the venae cavae. This fact is borne
witness to by Galen, whose words, when writing against Erasis-
tratus in regard to the origin and use of the veins and the coction
of the blood, are the following : "You will reply," he says, "that the
effect is so; that the blood is prepared in the liver, and is thence
transferred to the heart to receive its proper form and last perfec-
tion ; a statement which does not appear devoid of reason ; for no
great and perfect work is ever accomplished at a single effort, or
receives its final polish from one instrument. But if this be actually
so, then show us another vessel which draws the absolutely perfect
blood from the heart, and distributes it as the arteries do the spirits
over the whole body." Here then is a reasonable opinion not al-
lowed, because, forsooth, besides not seeing the true means of tran-
sit, he could not discover the vessel which should transmit the blood
from the heart to the body at large !
But had any one been there in behalf of Erasistratus, and of that
opinion which we now espouse, and which Galen himself acknowl-
edges in other respects consonant with reason, to have pointed to
the aorta as the vessel which distributes the blood from the heart to
the rest of the body, I wonder what would have been the answer of
V 6-1
10 THE BEGINNING OF MODERN MEDICINE
that most ingenious and learned man? Had he said that the artery
transmits spirits and not blood, he would indeed sufficiently have
answered Erasistratus, who imagined that the arteries contained
nothing but spirits; but then he would have contradicted himself,
and given a foul denial to that for which he had keenly contended in
his writings against this very Erasistratus, to-wit, that the blood in
substance is contained in the arteries, and not spirits ; a fact which
he demonstrated not only by many powerful arguments, but by
experiments.
But if the divine Galen will here allow, as in other places he
does, "that all the arteries of the body arise from the great artery,
and that this takes its origin from the heart; that all these vessels
naturally contain and carry blood ; that the three semi-lunar valves
situated at the orifice of the aorta prevent the return of the blood
into the heart, and that nature never connected them with this, the
most noble viscus of the body, unless for some most important end ;"
if, I say, this father of physic admits all these things, — and I quote
his own words, — I do not see how he can deny that the great artery
is the very vessel to carry the blood, when it has attained its highest
term of perfection, from the heart for distribution to all parts of the
body. Or would he perchance still hesitate, like all who have come
after him, even to the present hour, because he did not perceive the
route by which the blood was transferred from the veins to the
arteries, in consequence, as I have already said, of the intimate
connexion between the heart and lungs ? And this difficulty puzzled
anatomists not a little, when in their dissections they found the
pulmonary artery and left ventricle full of thick, black, and clotted
blood, plainly appears, when they felt themselves compelled to
affirm that the blood made its way from the right to the left ven-
tricle by sweating through the septum of the heart. But this fancy
I have already refuted. A new pathway for the blood must there-
fore be prepared and thrown open, and being once exposed, no fur-
ther difficulty will, I believe, be experienced by any one in admitting
what I have already proposed in regard to the pulse of the heart and
arteries, viz., the passage of the blood from the veins to the arteries,
and its distribution to the whole of the body by means of these
vessels.
THE BEGINNING OF MODERN MEDICINE 11
OF THE COURSE BY WHICH THE BLOOD IS CARRIED FROM THE VENA
CAVA INTO THE ARTERIES, OR FROM THE RIGHT INTO
THE LEFT VENTRICLE OF THE HEART
Since the intimate connexion of the heart with the lungs, which
is apparent in the human subject, has been the probable cause of the
errors that have been committed on this point, they plainly do amiss
who, pretending to speak of the parts of the animals generally, as
anatomists for the most part do, confine their researches to the
human body alone, and that when it is dead. They obviously act no
otherwise than he who, having studied the forms of a single com-
monwealth, should set about the composition of a general system of
polity ; or, who, having taken cognizance of the nature of a single
field, should imagine that he had mastered the science of agriculture ;
or who, upon the ground of one particular proposition, should pro-
ceed to draw general conclusions.
Had anatomists only been as conversant with the dissection of
the lower animals as they are with that of the human body, the mat-
ters that have hitherto kept them in perplexity of doubt would, in
my opinion, have met them freed from every kind of difficulty.
And, first, in fishes, in which the heart consists of but a single
ventricle, they having no lungs, the thing is sufficiently manifest.
Here the sac, which is situated at the base of the heart, and is the
part analogous to the auricle in man, plainly throws the blood into
the heart, and the heart, in its turn, conspicuously transmits it by
a pipe or artery, or vessel analogous to an artery ; these are the facts
which are confirmed by simple ocular inspection, as well as by a
division of the vessel, when the blood is seen to be projected by each
pulsation of the heart.
The same thing is also not difficult of demonstration in those
animals that have either no septum, or, as it were, no more than a
single ventricle to the heart, such as toads, frogs, serpents, and liz-
ards, which, although they have lungs in a certain sense, as they
have a voice, (and I have many observations by me on the admir-
able structure of the lungs of these animals, and matters appertain-
ing, which, however, I cannot introduce in this place,) still their
anatomy plainly shows that the blood is transferred in them from
the veins to the arteries in the same manner as in the higher animals,
viz., by the action of the heart ; the way, in fact, is patent, open, man-
ifest; there is no difficulty, no room for hesitating about it; for in
12 THE BEGINNING OF MODERN MEDICINE
them the matter stands precisely as it would in man, were the sep-
tum of his heart perforated or removed, or one ventricle made out
of two; and this being the case, I imagine that no one will doubt
as to the way by which the blood may pass from the veins into the
arteries.
But as there are actually more animals which have no lungs
than there are which be furnished with them, and in like manner a
greater number which have only one ventricle than there are which
have two, it is open to us to conclude, judging from the mass or mul-
titude of living creatures, that for the major part, and generally,
there is an open way by which the blood is transmitted from the
veins through the sinuses or cavities of the heart into the arteries.
I have, however, cogitating with myself, seen further, that the
same thing obtained more obviously in the embryos of those ani-
mals that have lungs; for in the foetus the four vessels belonging
to the heart, viz., the vena cava, the vena arteriosa or pulmonary
artery, the arteria venalis, or pulmonary vein, and the arteria magna
or aorta, are all connected otherwise than in the adult; a fact suffi-
ciently known to every anatomist. The first contact and union of
the vena cava with the arteria venosa or pulmonary veins, which
occurs before the cava opens properly into the right ventricle of the
heart, or gives off the coronary vein, a little above its escape from
the liver, is by a lateral anastomosis ; this is an ample foramen, of
an oval form, communicating between the cava and the arteria
venosa, or pulmonary vein, so that the blood is free to flow in the
greatest abundance by that foramen from the vena cava into the
arteria venosa, or pulmonary vein, and left auricle, and from thence
into the left ventricle ; and farther, in this foramen ovale, from that
part which regards the arteria venosa, or pulmonary vein, there is a
thin tough membrane, larger than the opening, extended like an
operculum or cover ; this membrane in the adult blocking up the for-
amen, and adhering on all sides, finally closes it up, and almost oblit-
erates every trace of it. This membrane, however, is so contrived
in the foetus, that falling loosely upon itself, it permits a ready
access to the lungs and heart, yielding a passage to the blood which
is streaming from the cava, and hindering the tide at the same time
from flowing back into that vein. All things, in short, permit us to
believe that in the embryo the blood must constantly pass by this
foramen from the vena cava into the arteria venosa, or pulmonary
THE BEGINNING OF MODERN MEDICINE 13
vein, and from thence into the left auricle of the heart; and having
once entered there, it can never regurgitate.
Another union is that by the vena arteriosa, or pulmonary
artery, and is effected when the vessel divides into two branches
after its escape from the right ventricle of the heart. It is as if to
the two trunks already mentioned a third were superadded, a kind
of arterial canal, carried obliquely from the vena arteriosa, or pul-
monary artery, to perforate and terminate in the arteria magna or
aorta. In the embryo, consequently, there are, as it were, two aor-
tas, or two roots of the arteria magna, springing from the heart.
This canalis arteriosus shrinks gradually after birth, and is at length
and finally almost entirely withered, and removed like the umbilical
vessels.
The canalis arteriosus contains no membrane or valve to direct
or impede the flow of the blood in this or that direction ; for at the
root of the vena arteriosa, or pulmonary artery, of which the canalis
arteriosus is the continuation in the foetus, there are three sigmoid
or semilunar valves, which open from within outwards, and oppose
no obstacle to the blood flowing in this direction or from the right
ventricle into the pulmonary artery or aorta; but they prevent all
regurgitation from the aorta or pulmonic vessels back upon the
right ventricle ; closing with perfect accuracy, they oppose an effec-
tual obstacle to everything of the kind in the embryo. So that there
is also reason to believe that when the heart contracts, the blood is
regularly propelled by the canal or passage indicated from the right
ventricle into the aorta.
What is commonly said in regard to these two great communi-
cations, to wit, that they exist for the nutrition of the lungs, is both
improbable and inconsistent ; seeing that in the adult they are closed
up, abolished, and consolidated, although the lungs, by reason of
their heat and motion, must then be presumed to require a larger
supply of nourishment. The same may be said in regard to the
assertion that the heart in the embryo does not pulsate, that it nei-
ther acts nor moves, so that nature was forced to make these com-
munications for the nutrition of the lungs. This is plainly false;
for simple inspection of the incubated egg, and of the embryo just
taken out of the uterus, shows that the heart moves precisely in
them as in adults, and that nature feels no such necessity. I have
myself repeatedly seen these motions, and Aristotle is likewise wit-
14 THE BEGINNING OF MODERN MEDICINE
ness of their reality. "The pulse," he observes, "inheres in the very
constitution of the heart, and appears in the beginning, as is learned
both from the dissection of living animals, and the formation of the
chick in the egg." But we further observe, that the passages in
question are not only pervious up to the period of birth in man as
well as in other animals, as anatomists in general have described
them, but for several months subsequently, in some indeed for sev-
eral years, not to say for the whole course of life ; as, for example,
in the goose, snipe, and various birds, and many of the smaller ani-
mals. And this circumstance it was, perhaps, that imposed upon
Botallus, who thought he had discovered a new passage for the
blood from the vena cava into the left ventricle of the heart ; and I
own that when I met with the same arrangement in one of the larger
members of the mouse family, in the adult state, I was myself led to
something of a like conclusion.
From this it will be understood that in the human embryo, and
in the embryo of animals in which the communications are not
closed, the same thing happens, namely, that the heart by its motion
propels the blood by obvious and open passages from the vena cava
into the aorta through the cavities of both the ventricles ; the right
one receiving the blood from the auricle, and propelling it by the
yena arteriosa, or pulmonary artery, and its continuation, named the
ductus arteriosus, into the aorta; the left, in like manner, charged
by the contraction of its auricle, which has received its supply
through the foramen ovale from the vena cava, contracting, and pro-
jecting the blood through the root of the aorta into the trunk of that
yessel.
In embryos, consequently, whilst the lungs are yet in a state
of inaction, performing no function, subject to no motion any more
than if they had not been present, nature uses the two ventricles of
the heart as if they formed but one, for the transmission of the
blood. The condition of the embryos of those animals which have
lungs, whilst these organs are yet in abeyance and not employed, is
the same as that of those animals which have no lungs.
So clearly, therefore, does it appear in the case of the foetus,
viz., that the heart by its action transfers the blood from the vena
cava into the aorta, and that by a route as obvious and open, as if
in the adult the two ventricles were made to communicate by the
removal of their septum. Since, then we find that in the greater
THE BEGINNING OP MODERN MEDICINE 15
number of animals, in all, indeed, at a certain period of their exist-
ence, the channels for the transmission of the blood through the
heart are so conspicuous, we have still to inquire wherefore in some
creatures — those, namely, that have warm blood, and that have at-
tained to the adult age, man among the number — we should not
conclude that the same thing is accomplished through the substance
of the lungs, which in the embryo, and at a time when the function
of these organs is in abeyance, nature effects by the direct passages
described, and which, indeed, she seems compelled to adopt through
want of a passage by the lungs ; or wherefore it should be better (for
nature always does that which is best) that she should close up the
various open routes, which she formerly made use of in the embryo
and foetus, and still uses in all other animals ; not only opening up
no new apparent channels for the passage of the blood, therefore,
but even entirely shutting up those which formerly existed.
And now the discussion is brought to this point, that they who
inquire into the ways by which the blood reaches the left ventricle
of the heart and pulmonary veins from the vena cava, will pursue
the wisest course if they seek by dissection to discover the causes
why in the larger and more perfect animals of mature age, nature
has rather chosen to make the blood percolate the parenchyma of
the lungs, than as in other instances chosen a direct and obvious
course — for I assume that no other path or mode of transit can be
entertained. It must be either because the larger and more perfect
animals are warmer, and when their adult heat greater — ignited, as
I might say, and requiring to be damped or mitigated ; therefore it
may be that the blood is sent through the lungs, that it may be tem-
pered by the air that is inspired, and prevented from boiling up, and
so becoming extinguished, or something of the sort. But to deter-
mine these matters and explain them satisfactorily, were to enter
on a speculation in regard to the office of the lungs and the ends for
which they exist; and upon such a subject, as well as what pertains
to eventilation, to the necessity and use of the air, etc., as also to
the variety and diversity of organs that exist in the bodies of ani-
mals in connexion with these matters, although I have made a vast
number of observations, still, lest I should be held as wandering too
wide of my present purpose, which is the use and motion of the
heart, and be charged of speaking of things beside the question, and
rather complicating and quitting than illustrating it, I shall leave
16 THE BEGINNING OF MODERN MEDICINE
such topics till I can more conveniently set them forth in a treatise
apart. And, now, returning to my immediate subject, I go on with
what yet remains for demonstration, viz., that in the more perfect
and warmer adult animals, and man, the blood passes from the right
ventricle of the heart by the vena arteriosa, or pulmonary artery,
into the lungs, and thence by the arteriae venosae, or pulmonary
veins, into the left auricle, and thence into the left ventricle of the
heart. And, first, I shall show that this may be so, and then I shall
show that it is so in fact.
THE BLOOD PERCOLATES THE SUBSTANCE OF THE LUNGS FROM THE RIGHT
VENTRICLE OF THE HEART INTO THE PULMONARY
VEINS AND LEFT VENTRICLE
That this is possible, and that there is nothing to prevent it
from being so, appears when we reflect on the way in which water
percolating the earth produces springs or rivulets, or when we spec-
ulate on the means by which the sweat passes through the skin, or
the urine through the parenchyma of the kidneys. It is well known
that persons who use the Spa waters, or those of La Madonna, in
the territories of Padua, or others of an acidulous or vitriolated nat-
ure, or who simply swallow drinks by the gallon, pass all off again
within an hour or two by urine. Such a quantity of liquid must
take some short time in the concoction; it must pass through the
liver; (it is allowed by all that the juices of the food we consume
pass twice through this organ in the course of the day;) it must
flow through the veins, through the parenchyma of the kidneys, and
through the ureters into the bladder.
To those, therefore, whom I hear denying that the blood, aye,
the whole mass of the blood may pass through the substance of the
lungs, even as the nutritive juices percolate the liver, asserting that
such a proposition to be impossible, and by no means to be enter-
tained as credible, I reply, with the poet, that they are of that race
of men who, when they will, assent full readily, and when they will
not, by no manner of means; who, when their assent is wanted,
fear, and when it is not, fear not to give it.
The parenchyma of the liver is extremely dense, so is that of
the kidney; the lungs, again, are of a much looser texture, and if
compared with the kidneys are absolutely spongy. In the liver there
is no forcing, no impelling power; in the lungs the blood is forced
THE BEGINNING OF MODERN MEDICINE 17
on by the pulse of the right ventricle, the necessary effect of whose
impulse is the distension of the vessels and pores of the lungs. And
then the lungs, in respiration, are perpetually rising and falling ; mo-
tions, the effect of which must needs be to open and shut the pores
and vessels, precisely as in the case of a sponge, and of parts having
a spongy structure, when they are alternately compressed and again
suffered to expand. The liver, on the contrary, remains at rest, and
is never seen to be dilated and constricted. Lastly, if no one denies
the possibility of the whole of the ingested juices passing through
the liver, in man, oxen, and the larger animals generally, in order
to reach the vena cava, and for this reason, that if nourishment is
to go on, these juices must needs get into the veins, and there is no
other way but the one indicated, why should not the same argu-
ments be held of avail for the passage of the blood in adults through
the lungs? Why not, with Columbus, that skillful and learned
anatomist, maintain and believe the like, from the capacity and struc-
ture of the pulmonary vessels ; from the fact of the pulmonary veins
and ventricle corresponding with them, being always found to con-
tain blood, which must needs have come from the veins, and by no
other passage save through the lungs ? Columbus, and we also, from
what precedes, from dissections, and other arguments, conceive the
thing to be clear. But as there are some who admit nothing unless
upon authority, let them learn that the truth I am contending for
can be confirmed from Galen's own words, namely, that not only
may the blood be transmitted from the pulmonary artery into the
pulmonary veins, then into the left ventricle of the heart, and from
thence into the arteries of the body, but that this is effected by the
ceaseless pulsation of the heart and the motion of the lungs in
breathing.
There are, as every one knows, three sigmoid or semilunar
valves situated at the orifice of the pulmonary artery, which effec-
tually prevent the blood sent into the vessel from returning into the
cavity of the heart. Now Galen, explaining the uses of these valves,
and the necessity for them, employs the following language : "There
is everywhere a mutual anastomosis and inosculation of the arteries
with the veins, and they severally transmit both blood and spirit, by
certain invisible and undoubtedly very narrow passages. Now if
the mouth of the vena arteriosa, or pulmonary artery, had stood in
like manner continually open, and nature had found no contrivance
18 THE BEGINNING OF MODERN MEDICINE
for closing it when requisite, and opening it again, it would have
been impossible that the blood could ever have passed by the invisi-
ble and delicate mouths, during the contractions of the thorax, into
the arteries ; for all things are not alike readily attracted or repelled ;
but that which is light is more readily drawn in, the instrument be-
ing dilated, and forced out again when it is contracted, than that
which is heavy ; and in like manner is anything drawn more rapidly
along an ample conduit, and again driven forth, than it is through a
narrow tube. But when the thorax is contracted, the pulmonary
veins, which are in the lungs, being driven inwardly, and powerfully
compressed on every side, immediately force out some of the spirit
they contain, and at the same time assume a certain portion of blood
by these subtile mouths ; a thing that could never come to pass were
the blood at liberty to flow back into the heart through the great
orifice of the pulmonary artery. But its return through the great
opening being prevented, when it is compressed on every side, a
certain portion of it distils into the pulmonary veins by the minute
orifices mentioned." And shortly afterwards, in the very next chap-
ter, he says : "The more the thorax contracts, the more it strives to
force out the blood, the more exactly do these membranes (viz., the
sigmoid valves) close up the mouth of the vessel, and suffer nothing
to regurgitate." The same fact he has also alluded to in a preced-
ing part of the tenth chapter : "Were there no valves, a three-fold
inconvenience would result, so that the blood would then perform
this lengthened course in vain; it would flow inwards during the
diastoles of the lungs, and fill all their arteries ; but in the systoles,
in the manner of the tide, it would ever and anon, like the Euripus,
flow backwards and forwards by the same way, with a reciprocating
motion, which would nowise suit the blood. This, however, may
seem a matter of little moment ; but if it meantime appear that the
function of respiration suffer, then I think it would be looked upon
as no trifle," etc. And again, and shortly afterwards : "And then a
third inconvenience, by no means to be thought lightly of, would
follow, were the blood moved backwards durings the expiration, had
not our Maker instituted those supplementary membranes [the sig-
moid valves]." Whence, in the eleventh chapter he concludes:
"That they have all a common use, (to wit, the valves), and that it
is to prevent regurgitation or backward motion ; each, however, hav-
ing a proper function, the one set drawing matters from the heart,
THE BEGINNING OF MODERN MEDICINE 19
and preventing their return, the other drawing matters into the
heart, and preventing their escape from it. For nature never in-
tended to distress the heart with needless labour, neither to bring
aught into the organ which it had been better to have kept away,
nor to take from it again aught which it was requisite should be
brought. Since, then, there are four great orifices in all, two in
either ventricle, one of these induces, the other educes." And again
he says : "Farther, since there is one vessel, consisting of a simple
tunic, implanted in the heart, and another having a double tunic,
extending from it, (Galen is here speaking of the right side of the
heart, but I extend his observations to the left side also,) a kind of
reservoir had to be provided, to which both belonging, the blood
should be drawn in by one, and sent out by the other."
This argument Galen adduces for the transit of the blood by the
right ventricle from the vena cava into the lungs ; but we can use it
with still greater propriety, merely changing the terms, for the pas-
sage of the blood from the veins through the heart into the arteries.
From Galen, however, that great man, that father of physicians, it
clearly appears that the blood passes through the lungs from the
pulmonary artery into the minute branches of the pulmonary veins,
urged to this both by the pulses of the heart and by the motions of
the lungs and thorax ; that the heart, moreover, is incessantly receiv-
ing and expelling the blood by and from its ventricles, as from a
magazine, or cistern, and for this end is furnished with four sets of
valves, two serving for the induction and two for the eduction of the
blood, lest, like the Euripus, it should be incommodiously sent hither
and thither, or flow back into the cavity which it should have
quitted, or quit the part where its presence was required, and so the
heart be oppressed with labour in vain, and the office of the lungs
be interfered with. Finally, our position that the blood is contin-
ually passing from the right to the left ventricle, from the vena cava
into the aorta, through the porous structure of the lungs, plainly ap-
pears from this, that since the blood is incessantly sent from the
right ventricle into the lungs by the pulmonary artery, and in like
manner is incessantly drawn from the lungs into the left ventricle,
as appears from what precedes and the position of the valves, it can-
not do otherwise than pass through continuously. And then, as the
blood is incessantly flowing into the right ventricle of the heart, and
is continually passed out from the left, as appears in like manner,
20 THE BEGINNING OF MODERN MEDICINE
and as is obvious both to sense and reason, it is impossible that the
blood can do otherwise than pass continually from the vena cava
into the aorta.
Dissection consequently shows distinctly what takes place [in
regard to the transit of the blood] in the greater number of animals,
and indeed in all, up to the period of their [foetal] maturity; and
that the same thing occurs in adults is equally certain, both from
Galen's words, and what has already been said on the subject, only
that in the former the transit is effected by open and obvious pas-
sages, in the latter by obscure porosities of the lungs and the minute
inosculations of vessels. Whence it appears that, although one ven-
tricle of the heart, the left to wit, would suffice for the distribution
of the blood over the body, and its eduction from the vena cava, as
indeed is done in those creatures that have no lungs, nature, never-
theless, when she ordained that the same blood should also perco-
late the lungs, saw herself obliged to add another ventricle, the
right, the pulse of which should force the blood from the vena cava
through the lungs into the cavity of the left ventricle. In this way,
therefore, it may be said that the right ventricle is made for the
sake of the lungs, and for the transmission of the blood through
them, not for their nutrition; seeing it were unreasonable to sup-
pose that the lungs required any so much more copious supply of
nutriment, and that of so much purer and more spiritous a kind, as
coming immediately from the ventricle of the heart, than either the
brain with its peculiarly pure substance, or the eyes with their lus-
trous and truly admirable structure, or the flesh of the heart itself,
which is more commodiously nourished by the coronary artery.
OF THE QUANTITY OF BLOOD PASSING THROUGH THE HEART FROM THE
VEINS TO THE ARTERIES : AND OF THE CIRCULAR
MOTION OF THE BLOOD
Thus far I have spoken of the passages of the blood from the
veins into the arteries, and of the manner in which it is transmitted
and distributed by the action of the heart; points to which some,
moved either by the authority of Galen or Columbus, or the reason-
ings of others, will give in their adhesion. But what remains to be
said upon the quantity and source of the blood which thus passes,
is of so novel and unheard-of character, that I not only fear injury to
myself from the envy of the few, but I tremble lest I have mankind
THE BEGINNING OF MODERN MEDICINE 21
at large for my enemies, so much doth wont and custom, that be-
come as another nature, and doctrine once sown and that hath
struck deep root, and respect for antiquity influence all men: Still
the die is cast, and my trust is in my love of truth, and the candour
that inheres in cultivated minds. And sooth to say, when I surveyed
my mass of evidence, whether derived from vivisections, and my va-
rious reflections on them, or from the ventricles of the heart and the
vessels that enter into and issue from them, the symmetry and size
of these conduits, — for nature doing nothing in vain, would never
have given them so large a relative size without a purpose, — or from
the arrangement and intimate structure of the valves in particular,
and of the other parts of the heart in general, with many other
things besides, I frequently and seriously bethought me, and long
revolved in my mind, what might be the quantity of blood that was
transmitted, in how short a time its passage might be effected, and
the like; and not finding it possible that this could be supplied by
the juices of the ingested aliment without the veins on the one hand
becoming drained, and the arteries on the other getting ruptured,
through the excessive charge of blood, unless the blood should
somehow find its way from the arteries into the veins, and so return
to the right side of the heart ; I began to think whether there might
not be A MOTION, AS IT WERE, IN A CIRCLE. Now this I
afterward found to be true ; and I finally saw that the blood, forced
by the action of the left ventricle into the arteries, was distributed
to the body at large, and its several parts, in the same manner as it
is sent through the lungs, impelled by the right ventricle into the
pulmonary artery, and that it then passes through the veins and
along the vena cava, and so round to the left ventricle in the manner
already indicated. Which motion may be allowed to call circular,
in the same way as Aristotle says that the air and rain emulate the
circular motion of the superior bodies ; for the moist earth, warmed
by the sun, evaporates ; the vapours drawn upwards are condensed,
and descending in the form of rain, moisten the earth again ; and by
this arrangement are generations of living things produced; and
in like manner too are tempests and meteors engendered by the cir-
cular motion, and by the approach and recession of the sun.
And so, in all likelihood, does it come to pass in the body,
through the motion of the blood ; the various parts are nourished,
cherished, quickened by the warmer, more perfect, vaporous, spirit-
22 THE BEGINNING OF MODERN MEDICINE
ous, and, as I may say, alimentive blood ; which, on the contrary, in
contact with these parts becomes cooled, coagulated, and, so to
speak, effete ; whence it returns to its sovereign the heart, as if to its
source, or to the inmost home of the body, there to recover its state
of excellence, or perfection.
Here it resumes its due fluidity and receives an infusion of nat-
ural heat — powerful, fervid, a kind of treasury of life, and is impreg-
nated with spirits, and it might be said with balsam ; and thence it
is again dispersed; and all this depends on the motion and action
of the heart.
The heart, consequently, is the beginning of life ; the sun of the
microcosm, even as the sun in his turn might well be designated the
heart of the world ; for it is the heart by whose virtue and pulse the
blood is moved, perfected, made apt to nourish, and is preserved
from corruption and coagulation ; it is the household divinity which,
discharging its function, nourishes, cherishes, quickens the whole
body, and is indeed the foundation of life, the source of all action.
But of these things we shall speak more opportunely when we come
to speculate upon the final cause of the motion of the heart.
Hence, since the veins are the conduits and vessels that trans-
port the blood, they are of two kinds, the cava and the aorta ; and
this is not by reason of there being two sides of the body, as Aris-
totle has it, but because of the differences of office; nor yet, as is
commonly said, in consequence of any diversity of structure, for in
many animals, as I have said, the vein does not differ from the artery
in the thickness of its tunics, but solely in virtue of their several des-
tinies and uses. A vein and an artery, both styled vein by the an-
cients, and that not undeservedly, as Galen has remarked, because
the one, the artery to-wit, is the vessel which carries the blood from
the heart to the body at large, the other or vein of the present day
bringing it back from the general system to the heart; the former
is the conduit from, the latter the channel to, the heart; the latter
contains the cruder, effete blood, rendered unfit for nutrition; the
former transmits the digested, perfect, peculiarly nutritive fluid.
EDUCATION
vouth :t
jurisconsults, or go!
eloquence alone v. IT
The education ••
cism in the monaste
two forms wer.^ in >t
up to * 9 nr>
ten.j - .
shoot -A's!
sic. • - tr;iinmt: -Aa-s .•.-•t'.
intellectual, :. -TTOV, Mtrotcfi. •
With the Kcfia anre < amc &
thors studied in the u'.'.^Hal. T'ni'
rope, and the higher cla.^- -.*•?, u-hn ha--.1
ignorant during the Middi< Agej«. be*.
The Reformation did much to bring this
of the middle orders.
FLORA
By Titian, 1477-1570. At Florence*
EDUCATION
IN THE SECOND VOLUME of this series we illustrated the educa-
tion of the Spartans, and the contributions to the science by Plato
and Aristotle. In all of this the child was subordinated to the state.
The Spartans made him a Stoic: Plato and Aristotle would have
made him a philosopher. Rome, on the other hand, as we saw in
the essays of Quintilian and Plutarch (volume III.), trained her
youth to be orators. They were either born statesmen, generals,
jurisconsults, or got their skill in these fields by actual practice; in
eloquence alone were they given any formal training.
The education of the Middle Ages was either that of scholasti-
cism in the monasteries or of knighthood in the tournament. The
two forms were in strong contrast. The young knight was brought
up to serve his mistress, the monk was taught to think woman a
temptation from the devil. The knight learned to ride, joust, swim,
shoot with the bow, hawk, play chess, and make verses in Italian or
Provengal. The monk learned grammar, logic, rhetoric, Latin,
mathematics, philosophy, astrology, and perhaps alchemy and mu-
sic. The knight's training was mostly physical. The monk's was
intellectual, but narrow, bigoted, harsh, and formal.
With the Renaissance came a new interest in the classical au-
thors studied in the original. Universities sprung up all over Eu-
rope, and the higher classes, who had been intellectually the most
ignorant during the Middle Ages, became the most enlightened.
The Reformation did much to bring this education within the reach
of the middle orders.
24 EDUCATION
John Sturm (1507-1589) of Strasburg introduced the study of
pure Ciceronian Latin into the schools in place of the spoken Latin
of the scholastics. The influence of this act has been enormous both
for good and bad. He was an embodiment of true scholarship, but
his work led to euphemism and artificial refinements.
Montaigne (1533-1592) gives a good picture of the education of
his time. He makes a strong plea for the fostering and development
of the originality of the child. His essay on education is given in
volume V.
Wolfgang Ratke (1571-?) did a great deal to systematize teach-
ing. His principal rules are these: I. Begin everything with
prayer. 2. Do all things in order, following nature. 3. Do one thing
at a time. 4. Emphasize by frequent repetition. 5. Teach first in
the mother tongue. 6. Proceed from the mother tongue to the other
languages. 7. Do not beat children (as did the monastic schools) to
make them learn. Give time for play. Do not teach more than two
hours at a time. Teach pupils to love their masters. Let them learn
the substance, not the words. 8. Let there be uniformity in teach-
ing and text books. 9. Teach things first, then the reasons for them.
Give examples before rules. Teach languages from the authors
themselves. 10. Teach inductively and by experiment.
As a couaterpoise to the new development of Protestant
schools, the Jesuits established schools all over Catholic Europe.
Lower education they made include grammar and syntax. Then
followed rhetoric and the languages. The pupils were taught not
only to read and write but to speak classical Latin. The higher
studies began with Aristotle's science and followed with his philos-
ophy. The climax of the course was a four years' training in
theology.
The educator most influential on the future developments of
the science was probably, however, Comenius. His great principle
was to follow nature closely, for example, in learning a dead lan-
guage to learn words and things together as we do the mother
tongue. His outline of the principles of education is given below.
25
COMENIUS
JOHN AMOS COMENIUS (KOMENSKI) was born in Moravia, 1592.
His parents, who belonged to the Moravian Brethren, died when he
was a child. He went to an elementary school at Stassnick, and en-
tered the Latin school at the rather late age of sixteen. After at-
tending the universities of Amsterdam and Heidelberg, he was ap-
pointed to the Moravian Brethren's school at Prerau. In 1618 he
was placed over the church and school at Fulneck. In 1621 the
Spanish troops swept away his property. Three years later the per-
secution of the Protestants in that locality began and in 1627 Come-
nius felt compelled to seek peace in Poland. He was summoned to
England in 1641 to superintend the improvement of the public
schools, but the civil war was on and he had to leave with his work
unaccomplished. For a while he found a home with Louis de Geer,
a rich Dutch merchant, but in 1648 returned to Poland to be head
bishop of his church. The next few years were spent in his church
work and in the founding of a model school.
Trouble broke out between the Moravians and Poles and Come-
nius again lost all his possessions, finding a home at last with Law-
rence de Geer, the son of his former patron. He died in 1670. He
helped to open education to the lower classes and continually sought
to find a method of instruction that would follow the example of
nature.
EDUCATIONAL IDEAS
THE PRINCIPLES OF FACILITY IN TEACHING AND IN LEARNING
I. We have already considered the means by which the edu-
cationist may attain his goal with certainty, we will now proceed
to see how these means can be suited to the minds of the pupils, so
that their use may be easy and pleasant.
V 6-2 •
26 EDUCATION
2. Following in the footsteps of nature we find that the pro-
cess of education will be easy
(i.) If it begin early, before the mind is corrupted.
(ii.) If the mind be duly prepared to receive it.
(iii.) If it proceed from the general to the particular.
(iv.) And from what is easy to what is more difficult.
(v.) If the pupil be not overburdened by too many subjects.
(vi.) And if progress be slow in every case.
(vii.) If the intellect be forced to nothing to which the natural
bent does not incline it, in accordance with its age and with the
right method.
(viii.) If everything be taught through the medium of the
senses.
(ix.) And if the use of everything taught be continually kept
in view.
(x.) If everything be taught according to one and the same
method.
These, I say, are the principles to be adopted if education is to
be easy and pleasant.
FIRST PRINCIPLE
3. Nature begins by a careful selection of materials.
For instance, for hatching a bird she selects fresh eggs and
those that contain pure matter. If the formation of the chicken have
already begun, it is in vain to expect any result.
4. Imitation. — The architect who wishes to erect a building,
needs a clear plot of ground, and, if there be a house already stand-
ing there, he must pull it down before he can build the new one.
5. The artist, too, does his best work on a clean canvas. If it
have already been painted on, or be dirty or rough, it must be
cleaned or smoothed before he can use it.
6. For the preservation of precious ointments, empty jars must
be procured, or those that are in use must be carefully cleansed of
their contents.
7. The gardener, too, prefers to plant young trees, or, if he
takes them too old, cuts off the branches in order that the sap may
not be dissipated. For this reason Aristotle placed "privation"
among the principles of nature, for he held that it was impossible
EDUCATION 27
to impress a new form on any material until the old one had been
removed.
8. Deviation. — It follows from this: (i) That it is best to
devote the mind to the pursuit of wisdom while it is still fresh, and
before it has acquired the habit of dissipating its strength over a
variety of occupations ; and that the later the education begins, the
harder it will be for it to obtain a hold, because the mind is already
occupied by other things. (2) That the result must be bad if a boy
be instructed by several teachers at once, since it is scarcely possible
for them all to use the same method, and, if they do not, the boy's
mind is drawn first in one direction and then in another, and its de-
velopment is thus hindered. (3) That it shows great lack of judg-
ment if moral instruction be not made the first point when the edu-
cation of children or of older boys is commenced ; since, when they
have been taught to control their feelings, they will be the more
fit to receive other instruction. Horse-tamers keep a horse under
absolute control with an iron bit, and ensure its obedience before
they teach it its paces. Rightly does Seneca say : "First learn vir-
tue, and then wisdom, since without virtue it is difficult to learn
wisdom." And Cicero says: "Moral philosophy makes the mind
fit to receive the seeds of further knowledge."
9. Rectification. — Therefore
(i.) Education should be commenced early.
(ii.) The pupil should not have more than one teacher in each
subject.
(iii.) Before anything else is done, the morals should be ren-
dered harmonious by the master's influence.
SECOND PRINCIPLE
10. Nature prepares its material so that it actually strives to
attain the form.
Thus the chicken in the egg, when sufficiently formed, seeks
to develop itself still further, moves, and bursts the shell or breaks
through it with its beak. After escaping from its prison, it takes
pleasure in the warmth and nutriment provided by its mother, opens
its beak expectantly and swallows its food greedily. It rejoices to
find itself under the open sky, exercises its wings, and, later on, uses
them with enjoyment ; in a word, it displays a keen desire to fulfill
28 EDUCATION
all its natural functions, though throughout the whole process of
development it advances step by step.
11. Imitation. — The gardener also must bring it about that the
plant, properly provided with moisture and with warmth, take pleas-
ure in its vigorous growth.
12. Deviation. — Therefore, those who drive boys to their stud-
ies, do them great harm. For what result can they expect? If a
man have no appetite, but yet takes food when urged to do so,
the result can only be sickness and vomiting, or at least indigestion
and indisposition. On the other hand, if a man be hungry, he is
eager to take food, digests it readily, and easily converts it into flesh
and blood. Thus Isocrates says : "He who is anxious to learn will
also be learned." And Quintilian says : "The acquisition of knowl-
edge depends on the will to learn, and this cannot be forced."
13. Rectification. — Therefore
(i.) The desire to know and to learn should be excited in boys
in every possible manner.
(ii.) The method of instruction should lighten the drudgery of
learning, that there may be nothing to hinder the scholars or deter
them from making progress with their studies.
14. The desire to learn is kindled in boys by parents, by mas-
ters, by the school, by the subjects of instruction, by the method of
teaching, and by the authority of the state.
15. By parents, if they praise learning and the learned in the
presence of their children, or if they encourage them to be indus-
trious by promising them nice books and clothes, or some other
pretty thing ; if they commend the teachers (especially him to whom
they entrust their sons) as much for their friendly feeling towards
the pupils as for their skill in teaching (for love and admiration are
the feelings most calculated to stimulate a desire for imitation) ;
finally, if, from time to time, they send the child to him with a small
present. In this way they will easily bring it about that the children
like their lessons and their teachers, and have confidence in them.
16. By the teachers, if they are gentle and persuasive, and do
not alienate their pupils from them by roughness, but attract them
by fatherly sentiments and words ; if they commend the studies that
they take in hand on account of their excellence, pleasantness, and
ease ; if they praise the industrious ones from time to time (to the
little ones they may give apples, nuts, sugar, etc.) ; if they call the
EDUCATION »
children to them, privately or in the class, and show them pictures
of the things that they must learn, or explain to them optical or geo-
metrical instruments, astronomical globes, and such-like things that
are calculated to excite their admiration ; or again, if they occasion-
ally give the children some message to carry to their parents. In a
word, if they treat their pupils kindly they will easily win their af-
fections, and will bring it about that they prefer going to school to
remaining at home.
17. The school itself should be a pleasant place, and attractive
to the eye both within and without. Within, the room should be
bright and clean, and its walls should be ornamented by pictures.
These should be either portraits of celebrated men, geograph-
ical maps, historical plans, or other ornaments. Without, there
should be an open place to walk and to play in (for this is absolutely
necessary for children, as we shall show later), and there should
also be a garden attached, into which the scholars may be allowed to
go from time to time and where they may feast their eyes on trees,
flowers and plants. If this be done, boys will, in all probability, go
to school with as much pleasure as to fairs, where they always hope
to see and hear something new.
18. The subjects of instruction themselves prove attractive to-
the young, if they are suited to the age of the pupil and are clearly
explained ; especially if the explanation be relieved by a humorous or
at any rate by a less serious tone. For thus the pleasant is com-
bined with the useful.
19. If the method is to excite a taste for knowledge, it must, in.
the first place, be natural. For what is natural takes place without
compulsion. Water need not be forced to run down a mountain-
side. If the dam, or whatever else holds in back, be removed, it
flows down at once. It is not necessary to persuade a bird to fly;
it does so as soon as the cage is opened. The eye and the ear need
no urging to enjoy a fine painting or a beautiful melody that is pre-
sented to them. In all these cases it is more often necessary to re-
strain than to urge on. The requisites of a natural method are
evident from the preceding chapter and from the rules that follow.
In the second place, if the scholars are to be interested, care
must be taken to make the method palatable, so that everything, no
matter how serious, may be placed before them in a familiar and at-
tractive manner; in the form of a dialogue, for instance, by pitting
30 EDUCATION
the boys against one another to answer and explain riddling ques-
tions, comparisons, and fables. But of this more in the proper place.
20. The civil authorities and the managers of schools can kin-
dle the zeal of the scholars by being present at public performances
(such as declarations, disputations, examinations, and promotions),
and by praising the industrious ones and giving them small presents
(without respect to person).
THIRD PRINCIPLE
21. Nature develops everything from beginnings, which, though
insignificant in appearance, possess great potential strength.
For instance, the matter out of which a bird is to be formed con-
sists of a few drops, which are contained in a shell, that they may be
easily warmed and hatched. But these few drops contain the whole
bird potentially, since, later on, the body of the chicken is formed
from the vital principle which is concentrated in them.
22. Imitation. — In the same way a tree, no matter how large it
may be, is potentially contained in the kernel of its fruit or in the
shoot at the end of one of its branches. If one or the other of these
be placed in the earth, a whole tree will be produced by the inner
force that it contains.
23. Terrible Deviation. — In direct opposition to this principle
a terrible mistake is generally made in school. Most teachers are
at pains to place in the earth plants instead of seeds, and trees in-
stead of shoots, since, instead of starting with the fundamental prin-
ciples, they place before their pupils a chaos of diverse conclusions
or the complete texts of authors. And yet it is certain that instruc-
tion rests on a very small number of principles, just as the earth is
composed of four elements (though in diverse forms) ; and that from
theses principles (in accordance with the evident limits of their pow-
ers of differentiation) an unlimited number of results can be deduced,
just as, in the case of a tree, hundreds of branches, and thou-
sands of leaves, blossoms, and fruits are produced from the original
shoot. Oh! may God take pity on our age, and open some man's
eyes, that he may see aright the true relations in which things stand
to one another, and may impart his knowledge to the rest of man-
kind. With God's assistance I hope, in my Synopsis of Christian
Wisdom, to give an earnest of my efforts to do so, in the modest
EDUCATION 31
hope that it may be of use to others whom God, in due season, may
call to carry on the work.
24. Rectification. — In the meantime we may draw three con-
clusions :
(i.) Every art must be contained in the shortest and most
practical rules.
(ii.) Each rule must be expressed in the shortest and clearest
words.
(iii.) Each rule must be accompanied by many examples, in
order that the use of the rule may be quite clear when fresh cases
arise.
FOURTH PRINCIPLE
25. Nature advances from what is easy to what is more difficult.
For example, the formation of an egg does not begin with the
hardest part, the shell, but with the contents. These are at first cov-
ered by a membrane ; it is not till later that the hard shell appears.
The bird that learns to fly accustoms itself first to stand on its legs,
then to move its wings gently, then to do so with more force until
it can raise itself from the ground, and last of all gains sufficient con-
fidence to fly through the air.
26. Imitation. — In the same way a carpenter's apprentice
learns, first to fell trees, then to saw them into planks and fasten
them together, and finally to build complete houses of them.
27. Various Deviations. — It is therefore wrong to teach the
unknown through the medium of that which is equally unknown,
as is the case:
(i.) If boys who are beginning Latin are taught the rules in
Latin. This is just as if the attempt were made to explain Hebrew
by Hebrew rules, or Arabic by Arabic rules.
(ii.) If these same beginners are given as assistance a Latin-
German instead of a German-Latin dictionary. For they do not
want to learn their mother-tongue by the aid of Latin, but to learn
Latin through the medium of the language that they already know.
(On this error we will say more in chap. xxii.).
(iii.) If boys are given a foreign teacher who does not under-
stand their language. For if they have no common medium through
which they can hold communications with him, and can only guess
32 EDUCATION
at what he is saying, can anything but a Tower of Babel be
the result?
(iv.) A deviation is made from the right method of teaching, if
boys of all nations (i. e., French, German, Bohemian, Polish, or Hun-
garian boys) are taught in accordance with the same rules of gram-
mar (those of Melanchthon or of Ramus 26, for example,) since each
of these languages stands in its own particular relation to Latin, and
this relation must be well understood if Latin is to be thoroughly
taught to boys of these several nationalities.
28. Rectification. — These errors may be avoided
(i.) If the teachers and their pupils talk the same language.
(ii.) If all explanations are given in the language that the pu-
pils understand.
(iii.) If grammars and dictionaries are adapted to the language
through the medium of which the new one is to be learned (that is
to say, the Latin Grammar to the mother-tongue, and Greek Gram-
mar to the Latin language).
(iv.) If the study of a new language be allowed to proceed
gradually and in such a way that the scholar learn first to under-
stand (for this is the easiest), then to write (for here there is time
for consideration), and lastly to speak (which is the hardest, because
the process is so rapid).
(v.) If, when Latin is combined with German, the German be
placed first as the best known, and the Latin follow.
(vi.) If the subject-matter be so arranged that the pupils get
to know, first, that which lies nearest to their mental vision, then
that which is moderately near, then that which is more remote, and
lastly, that which is farthest off. Therefore, if boys are being taught
something for the first time (such as logic or rhetoric), the illus-
trations should not be taken from subjects that cannot be grasped
by the scholars, such as theology, politics, or poetry, but should be
derived from the events of every-day life. Otherwise the boys will
understand neither the rules nor their application.
(vii.) If boys be made to exercise, first their senses (for this is
the easiest), then the memory, then the comprehension, and finally
the judgment. In this way a graded sequence will take place; for
all knowledge begins by sensuous perception ; then through the me-
dium of the imagination it enters the province of the memory ; then,
by dwelling on the particulars, comprehension of the universal
EDUCATION 33
arises; while finally comes judgment on the facts that have been
grasped, and in this way our knowledge is firmly established.
FIFTH PRINCIPLE
29. Nature does not overburden herself, but is content with a
little.
For instance, she does not demand two chickens from one egg,
but is satisfied if one be produced. The gardener does not insert a
number of grafts on one stock, but two at most, if he consider it very
strong.
30. Deviation. — The mental energies of the scholar are there-
fore dissipated if he have to learn many things at once, such as gram-
mar, rhetoric, poetic, Greek, etc., in one year (cf. the previous
chapter, Principle 4).
SIXTH PRINCIPLE
31. Nature does not hurry, but advances slowly.
For example, a bird does not place its eggs in the fire, in order
to hatch them quickly, but lets them develop slowly under the in-
fluence of natural warmth. Neither, later on, does it cram its chick-
ens with food that they may mature quickly (for this would only
choke them), but it selects their food with care and gives it to them
gradually in the quantities that their weak digestion can support.
32. Imitation. — The builder, too, does not erect the walls on
the foundations with undue haste and then straightway put on the
roof; since, unless the foundations were given time to dry and be-
come firm, they would sink under the superincumbent weight, and
the whole building would tumble down. Large stone buildings,
therefore, cannot be finished within one year, but must have a suit-
able length of time allotted for their construction.
33. Nor does the gardener expect a plant to grow large in the
first month, or to bear fruit at the end of the first year. He does
not, therefore, tend and water it every day, nor does he warm it with
fire or with quicklime, but is content with the moisture that comes
from heaven and with the warmth that the sun provides.
34. Deviation. — For the young, therefore, it is torture
(i.) If they are compelled to receive six, seven, or eight hours'
class instruction daily, and private lessons in addition.
(ii.) If they are overburdened with dictations, with exercises,
34 EDUCATION
and with the lessons that they have to commit to memory, until
nausea and, in some cases, insanity is produced.
If we take a jar with a narrow mouth (for to this we may com-
pare a boy's intellect) and attempt to pour a quantity of water into
it violently, instead of allowing it to trickle in drop by drop, what
will be the result? Without doubt the greater part of the liquid will
flow over the side, and ultimately the jar will contain less than if the
operation had taken place gradually. Quite as foolish is the action
of those who try to teach their pupils, not as much as they can as-
similate, but as much as they themselves wish ; for the faculties need
to be supported and not to be overburdened, and the teacher, like
the physician, is the servant and not the master of nature.
35. Rectification. — The ease and the pleasantness of study will
therefore be increased:
(i.) If the class instruction be curtailed as much as possible,
namely to four hours, and if the same length of time be left for pri-
vate study.
(ii.) If the pupils be forced to memorize as little as possible,
that is to say, only the most important things ; of the rest they need
only grasp the general meaning.
(iii.) If everything be arranged to suit the capacity of the pu-
pil, which increases naturally with study and age.
SEVENTH PRINCIPLE
36. Nature compels nothing to advance that is not driven for-
ward by its own mature strength.
For instance, a chicken is not compelled to quit the egg before
its limbs are properly formed and set ; is not forced to fly before its
feathers have grown; is not thrust from the nest before it is able
to fly well, etc.
A tree, too, does not put forth shoots before it is forced to do
so by the sap that rises from the roots, nor does it permit fruit to ap-
pear before the leaves and blossoms formed by the sap seek further
development, nor does it permit the blossoms to fall before the fruit
that they contain is protected by a skin, nor the fruit to drop before
it is ripe.
37. Deviation. — Now the faculties of the young are forced :
(i.) If the boys are compelled to learn things for which their
age and capacity are not yet suited.
EDUCATION 35
(ii.) If they are made to learn by heart or do things that have
not first been thoroughly explained and demonstrated to them.
38. Rectification. — From what has been said, it follows
(i.) That nothing should be taught to the young, unless it is
not only permitted but actually demanded by their age and mental
strength.
(ii.) That nothing should be learned by heart that has not
been thoroughly grasped by the understanding. Nor should any
feat of memory be demanded unless it is absolutely certain that the
boy's strength is equal to it.
(iii.) That nothing should be set boys to do until its nature has
been thoroughly explained to them, and rules for procedure have
been given.
EIGHTH PRINCIPLE
39. Nature assists its operations in every possible manner.
For example, an egg possesses its own natural warmth, but this
is assisted by the warmth of the sun and by the feathers of the bird
that hatches it. God, the father of nature, takes forethought for
this. The newly-hatched chicken, also, is warmed by the mother as
long as is necessary, and is trained by her in the various functions
of life. This we can see in the case of storks, who assist their young
by taking them on their backs and bearing them round the nest
while they exercise their wings. In the same way nurses help little
children. They teach them first to raise their heads and then to sit
up ; later on, to stand on their legs, and to move their legs prepara-
tory to walking ; then by degrees to walk and step out firmly. When
they teach them to speak they repeat words to them and point out
the objects that the words denote.
40. Deviation. — It is therefore cruelty on the part of a teacher
if he set his pupils work to do without first explaining it to
them thoroughly, or showing them how it should be done, and if he
do not assist them in their first attempts ; or if he allow them to toil
hard, and then loses his temper if they do not succeed in their en-
deavors.
What is this but to torture the young? it is just as if a nurse
were to force a child to walk, while it is still afraid to stand on its
legs, and beat it when it failed to do so. Nature's teaching is very
different, and shows that we ought to have patience with the weak
as long as their strength is insufficient.
36 EDUCATION
41. Rectification. — From this it follows:
(i.) That no blows should be given for lack of readiness to
learn (for, if the pupil do not learn readily, this is the fault of no one
but the teacher, who either does not know how to make the pupil
receptive of knowledge or does not take the trouble to do so).
(ii.) That the subjects that have to be learned by the pupils
should be so thoroughly explained to them, that they can under-
stand them as well as they understand their five fingers.
(iii.) That, as far as is possible, instruction should be given
through the senses, that it may be retained in the memory with less
effort.
42. (For example, the sense of hearing should always be con-
joined with that of sight, and the tongue should be trained in com-
bination with the hand. The subjects that are taught should not
merely be taught orally, and thus appeal to the ear alone, but should
be pictorially illustrated, and thus develop the imagination by the
help of the eye. Again, the pupils should learn to speak with their
mouths and at the same time to express what they say with their
hands, that no study may be proceeded with before what has already
been learned is thoroughly impressed on the eyes, the ears, the un-
derstanding, and the memory. With this object, it is desirable to
represent pictorially, on the walls of the class-room, everything that
is treated of in the class, by putting up either precepts and rules or
pictures and diagrams illustrative of the subjects taught. If this is
done, it is incredible how much it assists a teacher to impress his
instructions on the pupils' minds. It is also useful if the scholars
learn to write down in their note-books or among their collections of
idioms everything that they hear or read, since in this way the imag-
ination is assisted and it is easier to remember them later on.
NINTH PRINCIPLE
43. Nothing is produced by nature of which the practical ap-
plication is not soon evident.
For example, when a bird is formed it is soon evident that the
wings are intended for flying and the legs for running. In the same
way every part of a tree has its use, down to the skin and the bloom
that surround the fruit.
Therefore
44. Imitation. — The task of the pupil will be made easier, if
the master, when he teaches him anything, show him at the same
EDUCATION 37
time its practical application in everyday life. This rule must be
carefully observed in teaching languages, dialectic, arithmetic, ge-
ometry, physics, etc. If it be neglected, the things that you are ex-
plaining will seem to be monsters from the new world, and the
attitude of the pupil, who is indifferent whether they exist or no, will
be one of belief rather than of knowledge. When things are brought
under his notice and their use explained to him, they should be put
into his hands that he may assure himself of his knowledge and may
derive enjoyment from its application.
Therefore
45. Those things only should be taught whose application can
be easily demonstrated.
TENTH PRINCIPLE
46. Nature is uniform in all its operations.
For instance, the production of all birds, and, indeed, of all liv-
ing creatures, resembles that of any single bird which you may
choose. It is only in the minor details that there are differences.
So too in the case of plants, the development of one plant from its
seed, the planting and the growth of a single tree, serve as illustra-
tions of the way in which all the others, without exception, develop.
One leaf on a tree resembles all the others, and in this respect does
not change from year to year.
47. Deviation. — Differences of method, therefore, confuse the
young, and make their studies distasteful to them, since not only do
different teachers use different systems, but even individual teachers
vary their method. For example, languages are taught in one way,
dialectic in another, though both might be brought under the same
method, in accordance with the harmony of the universe, and the
universal and intimate relations that exist between objects and
words.
48. Rectification. — Henceforth, therefore
(i.) The same method of instruction must be used for all the
sciences, the same for all the arts, and the same for all languages.
(ii.) In each school the same arrangement and treatment
should be adopted for all studies.
(iii.) The class-books for each subject should, as far as is pos-
sible, be of the same edition.
In this way difficulties will be avoided and progress will be
made easy. — The Great Didactic.
TRANSLATION OF KEATING.
THE BEGINNING OF MODERN PHILOSOPHY
WE SAW in the second volume of this series that Greek philos-
ophy had a consecutive development starting with Thales and reach-
ing its climax in Aristotle. Modern philosophy, beginning with
Descartes, forms another connected story of the evolution of thought.
The Greek philosophers attacked mainly the problem of what is the
permanent reality in the universe : modern philosophy has begun to
see that the problem of the true nature of the universe is bound up
with the question of the real nature of the self.
Descartes (1596-1650) tried to sweep away all uncertainties and
start from one absolutely certain fact, "Cogito, ergo sum," as he ex-
pressed it, — "I think, and in so thinking I exist." Only what ap-
pealed to his mind as clearly as this prime truth was to be accepted
as a fact. He believed in the existence of God because he thought
there must exist some perfect, infinite Being which is the source of
imperfect, finite man. He felt that he could trust his senses as to
the material world because such a Being would not deceive. There-
fore he accepted the existence of matter as a substance co-ordinate
with mind, the essence of mind being thought, the essence of matter
being extension, the source of both being God.
Out of this conception of the duality of the universe, rose the
question of how mind and matter can act on each other. Geulincx
(1625-1669) denied the possibility of any interaction. He thought
mind and matter to be like two clocks that run in harmony, not
because they interact, but because both are controlled by their
maker. Thus Malebranche (1638-1715) declared that "we see all
THE ADORATION OF THE SHEPHERDS
By Correggio, 1494-1534.
ANTONIO ALLEGRI (CORREGGIO) was born at Correggio, near Parma, in
1494. He takes the name by which he is known from his native town.
But little is preserved about his life, and most of this is disputed. He early
attained local success, and painted the pictures in the cathedral and the church of
St. John at Parma. Among his other famous pictures are the "Marriage of St.
Catharine" in the Louvre, and "The Nativity" at Dresden.
He was a facile painter, and a great technician, but could not express thought
as could Michael Angelo, nor feeling as did Raphael.
3HT HO HOITAflOUA 3HT
ri * ''Hlcrn philosophy, beginning with
'^
' «c art,
co
to rfpiwdD 9ffJ bus ^ibadJfi^ sdJ nr asiufotq »m i
.J« TO l^fnsM*1''atrfiryi^ i*^*)}^ feuB^fel T^drf AVMlwriktei4^|t
with the question of tfc*WdB$».^X#^'**^ >d-T'',4>|tB ,9ivuoJ ail) n
Jrigi/cul.f gp.9iqx3 jou itii'ft ••> lud .iiEJ-jJnrfosJ Jfienj « bnB ,T3JoJ»:q alioR? K ?-.£•// oH
.(ssrfqBJI Ti'tl) <-.a gur/5 )1 ion
v ' ^- -'.»'..!-. "/'* .1* ^
to f/r ar*
^'?^«jk would not deceive. There-
; natter as a substance co-ordinate
>! niiod being thought, the essence of matter
being extension, the source of both being God.
Out of this conception of the duality of the univ e the
question ul how mind and matter can act on each other. Geulincx
(1625-1669) (icai^i the possibility of any inte* action. He thought
mind and matter to tie like two clocks that run in harmony, not
because they interact, but because both a: : l,v their
makrr. Thus Malebranche \IL Ve see ail
THE BEGINNING OF MODERN PHILOSOPHY 39
things in God," that "our minds exist in God as matter exists in
space," that things are known to us only through ideas, and these
ideas come from God.
Spinoza (1632-1677) transformed the dualism of Descartes into
a monism by making God the sole true substance, and mind and mat-
ter only His manifestations. Leibnitz (1646-1716) sought to over-
come Descartes' dualism by supposing the universe to be, not one
great unity, but made up of an infinite number of individualities, or,
as he called them, monads. He makes the essence of substance to be
life, mind, and activity. Each monad is an individuality, but some
only move, others live, others think though unconsciously, the high-
est are self-conscious. God is the supreme monad whence all others
radiate as light from the sun. The harmony of the world was estab-
lished at its creation. Thus Leibnitz practically added the concep-
tion of life and mind to the atomic theory of the Greek Demokritos.
Locke (1632-1674) took up the examination of the contents of
the mind anew. He opposed Descartes' doctrine of innate ideas
and Leibnitz's belief in the possibility of unconscious thought. He
thought the soul to be at the beginning a tabula rosa, an "unmarked
tablet," and that all ideas come from experience. His analysis of
the ideas of the mind marks the beginning of psychology. He agreed
with Descartes in our certainty of our own existence, argued for the
existence of God as the cause of our existence, and believed in the
existence of things or matter as the cause or occasion of our ideas.
Where he got his principle of causality he does not explain.
This idea of Locke's that substance is an abstract idea presup-
posed as the cause of our sensations is the starting ground of
Berkeley's idealism. Let us take an illustration. What can we actu-
ally mean by a thing — for instance, a bell ? We have a sensation of
sound, another of sight, a feeling of hardness or resistance, a tem-
perature sensation of coldness, perhaps a bitter taste of the brass.
All these sensations are states of our own consciousness, but they
are continually recurring together, and we take for granted some-
thing that we call a bell as their cause. Yet all we really experience
is a cluster of sensations. Now Berkeley admits that we do have
such clusters of ideas, and that consequently our experience is ex-
actly the same under his system as under the most out and out
materialism. Where Berkeley differs from materialism is in his
answer to the question, "What is the real nature of that something
40 THE BEGINNING OF MODERN PHILOSOPHY
which we presuppose as the cause of these groups of sensations?"
Berkeley's argument, in brief, is this: All we can actually experi-
ence is our self and the states of our own consciousness — all mental;
the only self-acting cause we know is our own will — also mental ;
since, then, the only reality and the only cause we can actually
know are mental, what right have we to suppose this unknown
something to be anything but mental? Thus Berkeley argues dead
matter out of existence and in its stead puts God, the cause of all
our sensations. Nature is a symbolism through which God speaks
to us.
Hume (1711-1776) hurled philosophy from idealism into scepti-
cism. Starting from Locke's theory that all knowledge comes from
experience, he argued against the possibility of any sure knowledge
or science whatever. He declared that he could not find the self at
all, that he saw no necessary connection between ideas, that cause
and effect are simply habits of thought formed by custom, and that
therefore any certain knowledge is impossible.
This scepticism of Hume woke Kant (1724-1804) "out of his
dogmatic slumber," and incited him to examine the elements of the
mind. His problem was, "How is mathematics possible? How is
natural science possible? Is metaphysics possible?" He found
elements in the mind besides those that come from experience. He
showed that although the contents of our minds are given by experi-
ence, the form is furnished by the active mind itself. Space and
time, cause and effect, design, reciprocity are all forms of thought
given by the active mind to phenomena, and the possibility of any
consciousness whatever depends upon the unifying activity of the
self. Things in themselves we cannot experience, phenomena must
come under the laws of thought in order to be correlated with the
rest of our consciousness. This is Kant's answer to the problem of
the possibility of knowledge. The laws of thought hold good for all
experience, but cannot go beyond it. Nature in itself we cannot
experience, but only its manifestations as the phenomena of our
consciousnesss. The soul is a thing in itself; we can never grasp
it. But for the very reason that it is not a part of our experience,
the soul in itself may not be bound by the laws of experience and the
will may be free. This is the necessary basis of morality. So, too,
God may exist outside the field of experience, and faith is always
possible.
THE BEGINNING OF MODERN PHILOSOPHY 41
The above outline is best amplified in the words of the thinkers
themselves. The development of philosophy since Kant belongs to
a later volume.
DESCARTES
RENE DESCARTES was born March 30, 1596, in the province of
Touraine. His mother died of consumption a few days after his
birth, and he was not expected to live. From 1604 to 1612 he was
under the Jesuits at La Fleche. The next year he was sent to Paris
to see life. After two years spent to this purpose, he busied himself
in his studies for two more, and then in 1617 enlisted as a volunteer
in the war against the Netherlands.
His military life lasted four years. While in camp during the
winter of 1619-20, he saw the possibility of solving geometrical theo-
rems by algebra. Thus was born analytical geometry. He also
thought • that he could apply his method to all changes, considering
them as matter in motion.
In 1641 he published his Meditations. These tried to sweep
away all preconceived notions and start from the one certain fact
"Cogito, ergo sum," "I think and in thinking I exist." Only what he
could apperceive with absolute clearness would he accept as true.
We have pointed out the development of his system in the intro-
duction above. It certainly has furnished much of the basis of all
succeeding philosophy. He accepted God in order to account for
himself, and the facts given by the senses because so clearly given
and because God would not deceive. As regards the changes in the
material world, his mathematical training led him to reduce them all
under the laws of mechanics, but his fear of religious persecution
prevented him giving these views full publicity.
In 1649 ne went to Stockholm on an invitation from Queen
Christina, but caught cold a few months later and died February II,
1650.
V 6-3
43 THE BEGINNING OF MODERN PHILOSOPHY
MEDITATIONS
ON THE FIRST PHILOSOPHY, IN WHICH THE EXISTENCE OF GOD, AND
THE REAL DISTINCTION OF MIND AND BODY ARE DEMONSTRATED
MEDITATION I.
OF THE THINGS OF WHICH WE MAY DOUBT
Several years have now elapsed since I first became aware that
I had accepted, even from my youth, many false opinions for true,
and that consequently what I afterwards based on such principles
was highly doubtful; and from that time I was convinced of the
necessity of undertaking once in my life to rid myself of all the
opinions I had adopted, and of commencing anew the work of build-
ing from the foundation, if I desired to establish a firm and abiding
superstructure in the sciences. But as this enterprise appeared to
me to be one of great magnitude, I waited until I had attained an
age so mature as to leave me no hope that at any stage of life more
advanced I should be better able to execute my design. On this
account, I have delayed so long that I should henceforth consider I
was doing wrong were I still to consume in deliberation any of the
time that now remains for action. To-day, then, since I have oppor-
tunely freed my mind from all cares, [and am happily disturbed by
no passions], and since I am in the secure possession of leisure in a
peaceable retirement, I will at length apply myself earnestly and
freely to the general overthrow of all my former opinions. But, to
this end, it will not be necessary for me to show that the whole of
these are false — a point, perhaps, which I shall never reach ; but as
even now my reason convinces me that I ought not the less carefully
to withhold belief from what is not entirely certain and indubitable,
than from what is manifestly false, it will be sufficient to justify the
rejection of the whole if I shall find in each some ground for doubt:
nor for this purpose will it be necessary even to deal with each be-
lief individually, which would be truly an endless labour; but, as
the removal from below the foundation necessarily involves the
downfall of the whole edifice, I will at once approach the criticism
of the principles on which all my former beliefs rested.
All that I have, up to this moment, accepted as possessed of the
THE BEGINNING OF MODERN PHILOSOPHY 43
highest truth and certainty, I received either from or through the
senses. I observed, however, that these sometimes misled us ; and it
is the part of prudence not to place absolute confidence in that by
which we have even once been deceived.
But it may be said, perhaps, that, although the senses occasion-
ally mislead us respecting minute objects, and such as are so far
removed from us as to be beyond the reach of close observation,
there are yet many other of their informations (presentations), of
the truth of which it is manifestly impossible to doubt ; as for exam-
ple, that I am in this place, seated by the fire, clothed in a winter
dressing-gown, that I hold in my hands this piece of paper, with
other intimations of the same nature. But how could I deny that I
possess these hands and this body, and withal escape being classed
with persons in a state of insanity, whose brains are so disordered
and clouded by dark bilious vapors as to cause them pertinaciously
to assert that they are monarchs when they are in the greatest pov-
erty; or clothed [in gold] and purple when destitute of any cover-
ing; or that their head is made of clay, their body of glass, or that
they are gourds? I should certainly be not less insane than they,
were I to regulate my procedure according to examples so extrava-
gant.
Though this be true, I must nevertheless here consider that I
am a man, and that, consequently, I am in the habit of sleeping, and
representing to myself in dreams those same things, or even some-
times others less probable, which the insane think are presented to
them in their waking moments. How often have I dreamt that I
was in these familiar circumstances, — that I was dressed, and occu-
pied this place by the fire, when I was lying undressed in bed ? At
the present moment, however, I certainly look upon this paper with
eyes wide awake ; the head which I now move is not asleep ; I extend
this hand consciously and with express purpose, and I perceive it;
the occurrences in sleep are not so distinct as all this. But I cannot
forget that, at other times, I have been deceived in sleep by similar
illusions; and, attentively considering those cases, I perceive so
clearly that there exist no certain marks by which the state of wak-
ing can ever be distinguished from sleep, that I feel greatly aston-
ished ; and in amazement I almost persuade myself that I am now
dreaming.
Let us suppose, then, that we are dreaming, and that all these
44 THB BEGINNING OF MODERN PHILOSOPHY
particulars — namely, the opening of the eyes, the motion of the head,
the forth-putting of the hands — are merely illusions ; and even that
we really possess neither an entire body nor hands such as we see.
Nevertheless, it must be admitted at least that the objects which
appear to us in sleep are, as it were, painted representations which
could not have been formed unless in the likeness of realities ; and,
therefore, that those general objects, at all events, — namely, eyes, a
head, hands, and an entire body — are not simply imaginary, but
really existent. For, in truth, painters themselves, even when they
study to represent sirens and satyrs by forms the most fantastic and
extraordinary, cannot bestow upon them natures absolutely new,
but can only make a certain medley of the members of different ani-
mals ; or if they chance to imagine something so novel that nothing
at all similar has ever been seen before, and such as is, therefore,
purely fictitious and absolutely false, it is at least certain that the
colours of which this is composed are real.
And on the same principle, although these general objects, viz.,
[a body], eyes, a head, hands, and the like, be imaginary, we are
nevertheless absolutely necessitated to admit the reality at least of
some other objects still more simple and universal than these, of
which, just as of certain real colours, all those images of things,
whether true or real, or false and fantastic, that are found in our
consciousness (cogitatio), are formed.
To this class of objects seem to belong corporeal nature in gen-
eral and its extension ; the figure of extended things, their quantity
and magnitude, and their number, as also the place in, and the time
during, which they exist, and other things of the same sort. We will
not, therefore, perhaps reason illegitimately if we conclude this that
Physics, Astronomy, Medicine, and all the other sciences that have
for their end the consideration of composite objects, are indeed of a
doubtful character; but that Arithmetic, Geometry, and the other
sciences of the same class, which regard merely the simplest and
most general objects, and scarcely inquire whether or not these are
really existent, contain somewhat that is certain and indubitable:
for whether I am awake or dreaming, it remains true that two and
three make five, and that a square has but four sides; nor does it
seem possible that truths so apparent can ever fall under a suspicion
of falsity [or incertitude].
Nevertheless, the belief that there is a God who is all-powerful,
THE BEGINNING OF MODERN PHILOSOPHY 45
and who created me, such as I am, has for a long time, obtained
steady possession of my mind. How, then, do I know that He has
not arranged that there should be neither earth, nor sky, nor any
extended thing, nor figure, nor magnitude, nor place, providing at
the same time, however, for [the rise in me of the perceptions of all
these objects, and] the persuasion that these do not exist otherwise
than as I perceive them? And further, as I sometimes think that
others are in error respecting matters of which they believe them-
selves to possess a perfect knowledge, how do I know that I am not
also deceived each time that I add together two and three, or num-
ber the sides of a square, or form some judgment still more simple,
if more simple indeed can be imagined? But perhaps Deity has not
been willing that I should be thus deceived, for He is said to be
supremely good. If, however, it were repugnant to the goodness of
Deity to have created me subject to constant deception, it would
seem likewise to be contrary to His goodness to allow me to be
occasionally deceived ; and yet it is clear that this is permitted.
Some, indeed, might perhaps be found who would be disposed rather
to deny the existence of a Being so powerful than to believe that
there is nothing certain. But let us for the present refrain from
opposing this opinion, and grant that all which is here said of Deity
is fabulous: nevertheless, in whatever way it be supposed that I
reached the state in which I exist, whether by fate, or chance, or by
an endless series of antecedents and consequents, or by any other
means, it is clear (since to be deceived and to err is a certain defect)
that the probability of my being so imperfect as to be the constant
victim of deception, will be increased exactly in proportion as the
power possessed by the cause, to which they assign my origin, is
lessened. To these reasonings I have assuredly nothing to reply,
but am constrained at last to avow that there is nothing of all that I
formerly believed to be true of which it is impossible to doubt, and
that not through thoughtlessness or levity, but from cogent and
maturely considered reasons; so that henceforward, if I desire to
discover anything certain, I ought not the less carefully to refrain
from assenting to those same opinions than to what might be shown
to be manifestly false.
But it is not sufficient to have made these observations; care
must be taken likewise to keep them in remembrance. For those
old and customary opinions perpetually recur — long and familiar
46 THE BEGINNING OP MODERN PHILOSOPHY
usage giving them the right of occupying my mind, even almost
against my will, and subduing my belief ; nor will I lose the habit of
deferring to them and confiding in them so long as I shall consider
them to be what in truth they are, viz., opinions to some extent
doubtful, as I have already shown, but still highly probable, and
such as it is much more reasonable to believe than to deny. It is for
this reason I am persuaded that I shall not be doing wrong, if, tak-
ing an opposite judgment of deliberate design, I become my own
deceiver, by supposing, for a time, that all those opinions are entirely
false and imaginary, until at length, having thus balanced my old by
my new prejudices, my judgment shall no longer be turned aside by
perverted usage from the path that may conduct to the perception of
truth.
For I am assured that, meanwhile, there will arise neither peril
nor error from this course, and that I cannot for the present yield too
much to distrust, since the end I now seek is not action but knowl-
edge.
I will suppose, then, not that Deity, who is sovereignly good
and the fountain of truth, but that some malignant demon, who is
at once exceedingly potent and deceitful, has employed all his arti-
fice to deceive me; I will suppose that the sky, the air, the earth,
colours, figures, sounds, and all external things, are nothing better
than illusions of dreams, by means of which this being has laid
snares for my credulity; I will consider myself as without hands,
eyes, flesh, blood, or any of the senses, and as falsely believing that
I am possessed of these ; I will continue resolutely fixed in this be-
lief, and if indeed by this means it be not in my power to arrive at the
knowledge of truth, I shall at least do what is in my power, viz.,
[suspend my judgment], and guard with settled purpose against
giving my assent to what is false, and being imposed upon by this
deceiver, whatever be his power and artifice.
But this undertaking is arduous, and a certain indolence insen-
sibly leads me back to my ordinary course of life; and just as the
captive, who, perchance, was enjoying in his dreams an imaginary
liberty, when he begins to suspect that it is but a vision, dreads
awakening, and conspires with the agreeable illusions that the de-
ception may be prolonged, so I, of my own accord, fall back into the
train of my former beliefs, and fear to arouse myself from my
slumber, lest the time of laborious wakefulness that would succeed
THE BEGINNING OF MODERN PHILOSOPHY 47
this quiet, rest, in place of bringing any light of day, should prove
inadequate to dispel the darkness that will arise from the difficulties
that have now been raised.
MEDITATION II.
OF THE NATURE OF THE HUMAN MIND ; AND THAT IT IS MORE EASILY
KNOWN THAN THE BODY
The Meditation of yesterday has filled my mind with so many
doubts, that it is no longer in my power to forget them. Nor do I see,
meanwhile, any principle on which they can be resolved ; and just as
if I had fallen all of a sudden into very deep water, I am so greatly
disconcerted as to be unable either to plant my feet firmly on the
bottom or sustain myself by swimming on the surface. I will, never-
theless, make an effort, and try anew the same path on which I had
entered yesterday, that is, proceed by casting aside all that admits
of the slightest doubt, not less than if I had discovered it to be
absolutely false ; and I will continue always in this track until I shall
find something that is certain, or at least, if I can do nothing more,
until I shall know with certainty that there is nothing certain.
Archimedes, that he might transport the entire globe from the place
it occupied to another, demanded only a point that was firm and im-
moveable; so also, I shall be entitled to entertain the highest ex-
pectations, if I am fortunate enough to discover only one thing that
is certain and indubitable.
I suppose accordingly, that all the things which I see are false
(fictitious) ; I believe that none of those objects which my fallacious
memory represents ever existed ; I suppose that I possess no senses ;
I believe that body, figure, extension, motion, and place are merely
fictions of my mind. What is there, then, that can be esteemed
true ? Perhaps this only, that there is absolutely nothing certain.
But how do I know that there is not something different alto-
gether from the objects I have now enumerated, of which it is im-
possible to entertain the slightest doubt? Is there not a God, or
some being, by whatever name I may designate him, who causes
these thoughts to arise in my mind ? But why suppose such a being,
for it may be I myself am capable of producing them? Am I then,
at least not something? But I before denied that I possessed senses
or a body ; I hesitate, however, for what follows from that? Am I so
dependent on the body and the senses that without these I cannot
48 THE BEGINNING OF MODERN PHILOSOPHY
exist ? But I had the persuasion that there was absolutely nothing
in the world, that there was no sky, no earth, neither minds nor bod-
ies ; was I not therefore, at the same time, persuaded that I did not
exist? Far from it; I assuredly existed, since I was persuaded. But
there is I know not what being, who is possessed at once of the high-
est power and the deepest cunning, who is constantly employing all
his ingenuity in deceiving me. Doubtless, then, I exist, since I am
deceived ; and, let him deceive me as he may, he can never bring it
about that I am nothing, so long as I shall be conscious that I am
something. So that it must, in fine, be maintained, all things being
maturely and carefully considered, that this proposition (pronunci-
atuwi) I am, I exist, is necessarily true each time it is expressed by
me, or conceived in my mind.
But I do not yet know with sufficient clearness what I am,
though assured that I am ; and hence, in the next place, I must take
care, lest perchance I inconsiderately substitute some other object" in
room of what is properly myself, and thus wander from truth, even
in that knowledge (cognition) which I hold to be one of all others
the most certain and evident. For this reason, I will now consider
anew what I formerly believ-ed myself to be, before I entered on the
present train of thought ; and of my previous opinion I will retrench
all that can in the least be invalidated by the grounds of doubt I
have adduced, in order that there may at length remain nothing but
what is certain and indubitable. What then did I formerly think I
was? Undoubtedly I judged that I was a man. But what is a man ?
Shall I say a rational animal ? Assuredly not ; for it would be neces-
sary forthwith to inquire into what is meant by an animal, and what
by rational, and thus from a single question, I should insensibly
glide into others, and these more 'difficult than the first ; nor do I now
possess enough of leisure to warrant me in wasting my time amid
subtleties of this sort. I prefer here to attend to the thoughts that
sprung up of themselves in my mind, and were inspired by my own
nature alone, when I applied myself to the consideration of what I
was. In the first place, then, I thought that I possessed a counte-
nance, hands, arms, and all the fabric of members that appears in a
corpse, and which I called by the name of a body. It further oc-
curred to me that I was nourished, that I walked, perceived, and
thought, and all those actions I referred to the soul ; but what the
soul itself was I either did not stay to consider, or, if I did, I imag-
THE BEGINNING OF MODERN PHILOSOPHY 49
ined that it was something extremely rare and subtle, like wind, or
flame, or ether, spread through my grosser parts. As regarded the
body, I did not even doubt of its nature, but thought I distinctly
knew it, and if I had wished to describe it according to the notions
I then entertained, I should have explained myself in this manner:
By body I understand all that can be terminated by a certain figure ;
that can be comprised in a certain space and so fill a certain space as
therefrom to exclude every other body; that can be perceived either
by the touch, sight, hearing, taste, or smell ; but by something for-
eign to it by which it is touched [and from which it receives the
impression] : for the power of self-motion, as likewise that of per-
ceiving and thinking, I hold as by no means pertaining to the nature
of body ; on the contrary, I was somewhat astonished to find such
faculties existing in some bodies.
But [as to myself, what can I now say that I am], since I sup-
pose there exists an extremely powerful, and, if I may so speak,
malignant being, whose whole endeavors are directed towards de-
ceiving me? Can I affirm that I possess any one of all these at-
tributes of which I have lately spoken as belonging to the nature of
a body? After attentively considering them in my own mind, I find
none of them that can properly be said to belong to myself. To
recount them were idle and tedious. Let us pass then to the attri-
butes of the soul. The first mentioned were the powers of nutrition
and walking; but, if it be true that I have no body, it is true like-
wise that I am capable neither of walking nor of being nourished.
Perception is another attribute of the soul; but perception too is
impossible without the body; besides, I have frequently, during
sleep, believed that I perceived objects which I afterwards observed
that I did not in reality perceive. Thinking is another attribute of
the soul ; and here I discover what properly belongs to myself. This
alone is inseparable from me. I am — I exist : this is certain ; but
how often ? As often as I think ; for perhaps it would even happen,
if I should wholly cease to think, that I should at the same time alto-
gether cease to be. I now admit nothing that is not necessarily true :
I am therefore, precisely speaking, only a thinking thing, that is, a
mind (mcns sive animus), understanding or reason, — terms whose sig-
nification was before unknown to me. I am, however a real thing,
and really existent; but what thing? The answer was, a thinking
thing. The question now arises, am I aught besides ? I will stimu-
50 THE BEGINNING OP MODERN PHILOSOPHY
late my imagination with a view to discover whether I am not still
something more than a thinking being. Now it is plain I am not
the assemblage of members called the human body ; I am not a thin
and penetrating air diffused through all these members, or flame, or
vapour, or breath, or any of all the things I can imagine ; for I sup-
posed that all these were not, and, without changing the supposi-
tion, I find that I still feel assured of my existence.
But it is true, perhaps, that those very things which I suppose to
be non-existent, because they are unknown to me, are not in truth
different from myself whom I know. This is a point I cannot deter-
mine, and do not now enter into any dispute regarding it. I can only
judge of things that are known to me; I am conscious that I exist,
and I who know that I exist inquire into who I am. It is, however,
perfectly certain that the knowledge of my existence, thus precisely
taken, is not dependent on things, the existence of which is as yet
unknown to me : and consequently it is not dependent on any of the
things I can feign in imagination. Moreover, the phrase itself, I
frame an image (efUngo), reminds me of my error; for I should in
truth frame one if I were to imagine myself to be anything, since to
imagine is nothing more than to contemplate the figure or image of a
corporeal thing; but I already know that I exist, and that it is pos-
sible at the same time that all those images, and in general all that
relates to the nature of body, are merely dreams [or chimeras].
From this I discover that it is not more reasonable to say, I will
excite my imagination that I may know more distinctly what I am,
than to express myself as follows : I am now awake, and perceive
something real ; but because my perception is not sufficiently clear, I
will of express purpose go to sleep that my dreams may represent
to me the object of my perception with more truth and clearness.
And, therefore, I know that nothing of all that I can embrace in im-
agination belongs to the knowledge which I have of myself, and that
there is need to recall with the utmost care the mind from this mode
of thinking, that it may be able to know its own nature with perfect
distinctness.
But what then am I ? A thinking thing, it has been said. But
what is a thinking thing? It is a thing that doubts, understands,
[conceives], affirms, denies, wills, refuses, that imagines also, and
perceives. Assuredly it is not little, if all these properties belong to
my nature. But why should they not belong to it? Am I not that
THE BEGINNING OP MODERN PHILOSOPHY 51
very being who now doubts of almost everything ; who, for all that,
understands and conceives certain things ; who affirms one alone as
true, and denies the others ; who desires to know more of them, and
does not wish to be deceived; who imagines many things, some-
times even despite his will ; and is likewise percipient of many, as if
through the medium of the senses. Is there nothing of all this as
true as that I am, even though I should be always dreaming, and
although he who gave me being employed all his ingenuity to de-
ceive me? Is there also any one of these attributes that can be
properly distinguished from my thought, or that can be said to be
separate from myself? For it is of itself so evident that it is I who
doubt, I who understand, and I who desire, that it is here unneces-
sary to add anything by way of rendering it more clear. And I am
as certainly the same being who imagines ; for, although it may be
(as I before supposed) that nothing I imagine is true, still the power
of imagination does not cease really to exist in me and to form part
of my thought. In fine, I am the same being who perceives, that is,
who apprehends certain objects as by the organs of sense, since, in
truth, I see light, hear a noise, and feel heat. But it will be said
that these presentations are false, and that I am dreaming. Let it
be so. At all events it is certain that I seem to see light, hear a noise,
and feel heat ; this cannot be false, and this is what in me is properly
called perceiving (sentire), which is nothing else than thinking.
From this I begin to know what I am with somewhat greater clear-
ness and distinctness than heretofore.
But, nevertheless, it still seems to me, that I cannot help believ-
ing, that corporeal things, whose images are formed by thought,
[which fall under the senses], and are examined by the same, are
known with much greater distinctness than that I know not what
part of myself which is not imaginable ; although in truth, it
may seem strange to say that I know and comprehend with
greater distinctness things whose existence appears to me doubtful,
that are unknown, and do not belong to me, than others of whose
reality I am persuaded, that are known to me, and appertain to my
proper nature ; in a word, than myself. But I see clearly what is the
state of the case. My mind is apt to wander, and will not yet submit
to be restrained within the limits of truth. Let us therefore leave the
mind to itself once more, and, according to it every kind of liberty,
[permit it to consider the objects that appear to it from without],
52 THE BEGINNING OF MODERN PHILOSOPHY
in order that, having afterwards withdrawn it from these gently and
opportunely, [and fixed it on the consideration of its being and the
properties it finds in itself], it may then be the more easily con-
trolled.
Let us now accordingly consider the objects that are commonly
thought to be [the most easily, and likewise], the most distinctly
known, viz., the bodies we touch and see ; not, indeed, bodies in gen-
eral, for these general notions are usually somewhat more confused,
but one body in particular. Take, for example, this piece of wax ; it
is quite fresh, having been but recently taken from the bee-hive ; it
has not yet lost the sweetness of the honey it contained ; it still re-
tains somewhat of the odour of the flowers from which it was gath-
ered ; its colour, figure, size, are apparent (to the sight) ; it is hard,
cold, easily handled ; and sounds when struck upon with the finger.
In fine, all that contributes to make a body as distinctly known as
possible, is found in the one before us. But, while I am speaking,
let it be placed near the fire — what remained of the taste exhales, the
smell evaporates, the colour changes, its figure is destroyed, its size
increases it becomes a liquid, it grows hot, it can hardly be handled,
and, although struck upon, it emits no sound. Does the same wax
still remain after this change? It must be admitted that it does
remain ; no one doubts it or judges otherwise. What, then, was it I
knew with so much distinctness in the piece of wax? Assuredly, it
could be nothing at all that I observed by means of the senses, since
all the things that fell under taste, smell, sight, touch, and hearing
are changed, and yet the same wax remains. It was perhaps what I
now think, viz., that this wax was neither the sweetness of honey,
the pleasant odour of flowers, the whiteness, the figure, nor the
sound, but only a body that a little before appeared to me conspicu-
ous under these forms, and which is now perceived under others.
But, to speak precisely, what is it that I imagine when I think of it in
this way ? Let it be attentively considered, and, retrenching all that
does not belong to the wax, let us see what remains. There cer-
tainly remains nothing, except something extended, flexible and
moveable. But what is meant by flexible and moveable? Is it not
that I imagine that the piece of wax, being round, is capable of be-
coming square, or of passing from a square into a triangular figure ?
Assuredly such is not the case, because I conceive that it admits of
an infinite variety of similar changes ; and I am, moreover, unable
THE BEGINNING OF MODERN PHILOSOPHY 53
to compass this infinity by imagination, and consequently this con-
ception which I have of the wax is not the product of the faculty of
imagination. But what now of this extension? Is it not also un-
known ? for it becomes greater when the wax is melted, greater when
it is boiled, and greater still when the heat increases; and I should
not conceive [clearly and] according to the truth, the wax as it is, if
I did not suppose that the piece we are considering admitted even of
a wider variety of extension than I ever imagined. I must, there-
fore, admit that I cannot even comprehend by imagination what the
piece of wax is, and that it is the mind alone (mens Lat., entendement,
F.) which perceives it. I speak of one piece in particular ; for, as to
wax in general, this is still more evident. But what is the piece o£
wax that can be perceived only by the [understanding or] mind ? It
is certainly the same which I see, touch, imagine ; and, in fine, it is
the same which, from the beginning I believed it to be. But (and
this it is of moment to observe) the perception of it is neither an act
of sight, of touch, nor of imagination, and never was either of these,
though it might formerly seem so, but is simply an intuition
(inspectio) of the mind, which may be imperfect and confused, as it
formerly was, or very clear and distinct, as it is at present, according
as the attention is more or less directed to the elements which it con-
tains, and of which it is composed.
But, meanwhile, I feel greatly astonished when I observe [the
weakness of my mind, and] its proneness to error. For although,
without at all giving expression to what I think, I consider all this in
my own mind, words yet occasionally impede my progress, and I am
almost led into error by the terms of ordinary language. We say,
for example, that we see the same wax when it is before us,
and not that we judge it to be the same from its retaining
the same colour and figure; whence I should forthwith be dis-
posed to conclude that the wax is known by the act of sight,
and not by the intuition of the mind alone, were it not for
the analogous instance of human beings passing on in the street
below, as observed from a window. In this case I do not fail to say
that I see the men themselves, just as I say that I see the wax; and
yet what do I see from the window beyond hats and cloaks that
might cover artificial machines, whose motions might be determined
by springs? But I judge that there are human beings from these
appearances, and thus I comprehend, by the faculty of judgment
54 THE BEGINNING OF MODERN PHILOSOPHY
alone which is in the mind, what I believed I saw with my eyes.
The man who makes it his aim to rise to knowledge superior to
the common, ought to be ashamed to seek occasions of doubting
from the vulgar forms of speech : instead, therefore, of doing this,
I shall proceed with the matter in hand, and inquire whether I had
a clearer and more perfect perception of the piece of wax when I first
saw it, and when I thought I knew it by means of the external sense
itself, or, at all events, by the common sense (sensus communis), as it
is called, that is by the imaginative faculty ; or whether I rather ap-
prehend it more clearly at present, after having examined with
greater care, both what it is, and in what way it can be known. It
would certainly be ridiculous to entertain any doubt on this point.
For what, in that first perception, was there distinct? What did I
perceive which any animal might not have perceived? But when I
distinguish from the exterior forms, and when, as if I had stripped
it of its vestments, I consider it quite naked, it is certain, although
some error may still be found in my judgment, that I cannot, never-
theless, thus apprehend it without possessing a human mind.
But, finally, what shall I say of the mind itself, that is, of my-
self? for as yet I do not admit that I am anything but mind. What
then ! I who seem to possess so distinct an apprehension of the piece
of wax, — do I not know myself, both with greater truth and certi-
tude, and also much more distinctly and clearly? For if I judge that
the wax exists because I see it, it assuredly follows, much more evi-
dently, that I myself am or exist, for the same reason ; for it is possi-
ble that what I see may not in truth be wax, and that I do not even
possess eyes with which to see anything ; but it cannot be that when
I see, or, which comes to the same thing, when I think I see, I myself
who think am nothing. So likewise, if I judge that the wax exists be-
cause I touch it, it will still also follow that I am ; and if I determine
that my imagination, or any other cause, whether it be, persuades
me of the existence of wax, I will still draw the same conclusion.
And what is here remarked of the piece of wax, is applicable
to all the other things that are external to me. And further, if the
[notion or] perception of wax appeared to me more precise and dis-
tinct, after that not only sight and touch, but many other causes be-
sides, rendered it manifest to my apprehension, with how much
greater distinctness must I now know myself, since all the reasons
that contribute to the nature of wax, or of any other body whatever,
THE BEGINNING OF MODERN PHILOSOPHY 55
manifest still better the nature of my mind ? And there are besides
so many other things in the mind itself that contribute to the illus-
tration of its nature, that those dependent on the body, to which I
have here referred, scarcely merit to be taken into account.
But, in conclusion, I find I have insensibly reverted to the point
I desired ; for, since it is now manifest to me that bodies themselves
are not properly perceived by the senses nor by the faculty of imag-
ination, but by the intellect alone ; and since they are not perceived
because they are seen and touched, but only because they are under-
stood [or rightly comprehended by thought], I readily discover that
there is nothing more easily or clearly apprehended than my own
mind. But because it is difficult to rid one's self so promptly of an
opinion to which one has been long accustomed, it will be desirable
to tarry for some time at this stage, that, by long continued medita-
tion, I may more deeply impress upon my memory this new
knowledge.
MEDITATION III.
OF GOD
With reference to these ideas of corporeal things that are clear
and distinct, there are some which, as appears to me, might have
been taken from the idea I have of myself, as those of substance,
duration, number, and the like. For when I think that a stone is a
substance, although I conceive that I am a thinking and non-
extended thing, and that the stone, on the contrary, is extended and
unconscious, there being thus the greatest diversity between the two
concepts, — yet these two ideas seem to have this in common that
they both represent substances. In the same way, when I think of
myself as now existing, and recollect besides that I existed some-
time ago, and when I am conscious of various thoughts whose num-
ber I know, I then acquire the ideas of duration and number, which
I can afterwards transfer to as many objects as I please. With re-
spect to the other qualities that go to make up the ideas of corporeal
objects, viz., extension, figure, situation, motion, it is true that they
are not formally in me, since I am merely a thinking being ; but be-
cause they are only certain modes of substance, and because I myself
am a substance, it seems possible that they may be contained in me
eminently.
There only remains, therefore, the idea of God, in which I must
56 THE BEGINNING OF MODERN PHILOSOPHY
consider whether there is anything that cannot be supposed to orig-
inate with myself. By the name God, I understand a substance in-
finite, [eternal, immutable], independent, all-knowing, all-powerful,
and by which I myself, and every other thing that exists, if any such
there be, were created. But these properties are so great and excel-
lent, that the more attentively I consider them the less I feel per-
suaded that the idea I have of them owes its origin to myself alone.
And thus it is absolutely necessary to conclude, from all that I have
before said, that God exists : for though the idea of substance be in
my mind owing to this, that I myself am a substance, I should not,
however, have the idea of an infinite substance, seeing I am a finite
being, unless it were given me by a substance in reality infinite.
And I must not imagine that I do not apprehend the infinite by
a true idea, but only by a negation of the infinite, in the same way
that I comprehend repose and darkness by the negation of motion
and light: since, on the contrary, I clearly perceive that there is
more reality in the infinite substance than in the finite, and therefore
that in some way I possess the perception (notion) of the infinite
before that of the finite, that is, the perception of God before that
of myself, for how could I know that I doubt, desire, or that some-
thing is wanting to me, and that I am not wholly perfect, if I pos-
sessed no idea of a being more perfect than myself, by comparison
of which I knew the deficiencies of my nature ?
And it cannot be said that this idea of God is perhaps materially
false, and consequently that it may have arisen from nothing, [in
other words, that it may exist in me from my imperfection], as I
before said of the ideas of heat and cold, and the like : for, on the
contrary, as this idea is very clear and distinct, and contains in itself
more objective reality than any other, there can be no one of itself
more true, or less open to the suspicion of falsity.
The idea, I say, of a being supremely perfect, and infinite, is in
the highest degree true; for, although, perhaps, we may imagine
that such a being does not exist, we cannot, nevertheless, suppose
that his idea represents nothing real, as I have already said of the
idea of cold. It is likewise clear and distinct in the highest degree,
since whatever the mind clearly and distinctly conceives as real or
true, and as implying any perfection, is contained entire in this idea.
And this is true, nevertheless, although I do not comprehend the
infinite, although there may be in God an infinity of things that I
THE BEGINNING OP MODERN PHILOSOPHY 57
cannot comprehend, nor perhaps even compass by thought in any-
way ; for it is of the nature of the infinite that it should not be com-
prehended by the finite; and it is enough that I rightly understand
this, and judge that all which I clearly perceive, and in which I know
there is some perfection, and perhaps also an infinity of properties
of which I am ignorant, are formally or eminently in God, in order
that the idea I have of him may become the most true, clear, and
distinct of all the ideas in my mind.
But perhaps I am something more than I suppose myself to be,
and it may be that all those perfections which I attribute to God,
in some way exist potentially in me, although they do not yet show
themselves, and are not reduced to act. Indeed, I am already con-
scious that my knowledge is being increased [and perfected] by de-
grees ; and I see nothing to prevent it from thus gradually increasing
to infinity, nor any reason why, after such increase and perfection,
I should not be able thereby to acquire all the other perfections of
the Divine nature ; nor, in fine, why the power I possess of acquiring
those perfections, if it really now exist in me, should not be sufficient
to produce the ideas of them. Yet, on looking more closely into the
matter, I discover that this cannot be ; for in the first place, although
it were true that my knowledge daily acquired new degrees of per-
fection, and although there were potentially in my nature much that
was not as yet actually in it, still all these excellencies make not the
slightest approach to the idea I have of the Deity, in whom there is
no perfection merely potentially [but all actually] existent; for it
is even an unmistakable token of imperfection in my knowledge, that
it is augmented by degrees. Further, although my knowledge in-
crease more and more, nevertheless I am not, therefore, induced to
think that it will ever be actually infinite, since it can never reach
that point beyond which it shall be incapable of further increase.
But I conceive God as actually infinite, so that nothing can add to
his perfection. And, in fine, I readily perceive that the objective
being of an idea cannot be produced by a being that is merely poten-
tially existent, which, properly speaking, is nothing, but only by a
being existent formally or actually.
And, truly, I see nothing in all that I have now said which it is
not easy for any one, who shall carefully consider it, to discern the
natural light ; but when I allow my attention in some degree to relax,
the vision of my mind being obscured, and, as it were, blinded by
V 6-4
58 THE BEGINNING OP MODERN PHILOSOPHY
the images of sensible objects, I do not readily remember the reason
why the idea of a being more perfect than myself, must of necessity
have proceeded from a being in reality more perfect. On this ac-
count I am here desirous to inquire further, whether I, who possess
this idea of God, could exist supposing there were no God. And I
ask, from whom could I, in that case, derive my existence? Perhaps
from myself, or from my parents, or from some other causes less
perfect than God ; for anything more perfect, or even equal to God,
cannot be thought or imagined. But if I [were independent of every
other existence, and] were myself the author of my being, I should
doubt of nothing, and, in fine, no perfection would be wanting to
me; for I should have bestowed upon myself every perfection of
which I possess the idea, and I should thus be God. And it must not
be imagined that what is now wanting to me is perhaps of more dif-
ficult acquisition than that of which I am already possessed; for,
on the contrary, it is quite manifest that it was a matter of much
higher difficulty that I, a thinking being, should arise from nothing,
than it would be for me to acquire the knowledge of many things
of which I am ignorant, and which are merely the accidents of a
thinking substance; and certainly, if I possessed of myself the
greater perfection of which I have now spoken, [in other words, if
I were the author of my own existence], I would not at least have
denied to myself things that may be more easily obtained, [as that
infinite variety of knowledge of which I am at present destitute].
I could not, indeed, have denied myself any property which I per-
ceive is contained in the idea of God, because there is none of these
that seems to me to be more difficult to make or acquire; and if
there were any that should happen to be more difficult to acquire,
they would certainly appear so to me (supposing that I myself were
the source of the other things I possess), because I should discover
in them a limit to my power. And though I were to suppose that I
always was as I now am, I should not, on this ground, escape the
force of these reasonings, since it would not follow, even on this
supposition, that no author of my existence needed to be sought
after. For the whole of my life may be divided into an infinity of
parts, each of which is in no way dependent on any other ; and, ac-
cordingly, because I was in existence a short time ago, it does not
follow that I must now exist, unless in this moment some cause
create me anew, as it were, — that is, conserve me. In truth, it is
THE BEGINNING OF MODERN PHILOSOPHY 59
perfectly clear and evident to all who will attentively consider the
nature of duration, that the conservation of a substance, in each
moment of its duration, requires the same power and act that would
be necessary to create it, supposing it were not yet in existence ; so
that it is manifestly a dictate of the natural light that conservation
and creation differ merely in respect of our mode of thinking [and
not in reality]. All that is here required, therefore, is that I interro-
gate myself to discover whether I possess any power by means of
which I can bring it about that I, who now am, shall exist a moment
afterwards ; for, since I am merely a thinking thing (or since, at
least, the precise question, in the meantime, is only of that part of
myself), if such a power resided in me, I should, without doubt, be
conscious of it; but I am conscious of no such power, and thereby
I manifestly know that I am dependent upon some being different
from myself.
But perhaps the being upon whom I am dependent, is not God,
and I have been produced either by my parents, or by some causes
less perfect than Deity. This cannot be : for, as I before said, it is
perfectly evident that there must at least be as much reality in the
cause as in its effect; and accordingly, since I am a thinking thing,
and possess in myself an idea of God, whatever in the end be the
cause of my existence, it must of necessity be admitted that it is like-
wise a thinking being, and that it possesses in itself the idea and all
the perfections I attribute to Deity. Then it may again be inquired
whether this cause owes its origin and existence to itself, or to some
other cause. For if it be self-existent, it follows, from what I have
before laid down, that this cause is God; for since it possesses the
perfection of self-existence, it must likewise, without doubt, have the
power of actually possessing every perfection of which it has the
idea, — in other words, all the perfections I conceive to belong to
God. But if it owes its existence to another cause than itself, we
demand again, for a similar reason, whether this second cause exists
of itself or through some other, until, from stage to stage, we at
length arrive at an ultimate cause, which will be God. And it is
quite manifest that in this matter there can be no infinite regress
of causes, seeing that the question raised respects not so much the
cause which once produced me, as that by which I am this moment
conserved.
Nor can it be supposed that several causes concurred in my pro-
60 THE BEGINNING OF MODERN PHILOSOPHY
duction, and that from one I received the idea of one of the perfec-
tions I attribute to Deity, and from another the idea of some other,
and thus that all those perfections are indeed found somewhere in
the universe, but do not all exist together in a single being who is
God ; for, on the contrary, the unity, the simplicity or inseparability
of all the properties of Deity, is one of the chief perfections I con-
ceive him to possess ; and the idea of this unity of all the perfections
of Deity could certainly not be put into my mind by any cause from
which I did not likewise receive the ideas of all the other perfections ;
for no power could enable me to embrace them in an inseparable
unity, without at the same time giving me the knowledge of what
they were [and of their existence in a particular mode].
Finally, with regard to my parents [from whom it appears I
sprung] , although all that I believed respecting them be true, it does
not, nevertheless, follow that I am conserved by them, or even that
I was produced by them, in so far as I am a thinking being. All
that, at the most, they contributed to my origin was the giving of
certain dispositions (modifications) to the matter in which I have
hitherto judged that I or my mind, which is what alone I now con-
sider to be myself, is enclosed ; and thus there can here be no diffi-
culty with respect to them, and it is absolutely necessary to conclude
from this alone that I am, and possess the idea of a being absolutely
perfect, that is, of God, that his existence is most clearly demon-
strated.
There remains only the inquiry as to the way in which I re-
ceived this idea from God ; for I have not drawn it from the senses,
nor is it even presented to me unexpectedly, as is usual with the
ideas of sensible objects, when these are presented, or appear to be
presented to the external organs of the senses; it is not even a pure
production or fiction of my mind, for it is not in my power to take
from or add to it ; and consequently there remains the same alterna-
tive that is innate, in the same way as is the idea of myself. And,
in truth, it is not to be wondered that God, at my creation, implanted
this idea in me, that it might serve, as it were, for the mark of the
workman impressed on his work; and it is not also necessary that
the mark should be something different from the work itself; but
considering only that God is my creator, it is highly probable that he
in some way fashioned me after his own likeness, in which is con-
tained the idea of God, by the same faculty by which I apprehend
THE BEGINNING OF MODERN PHILOSOPHY 61
myself, — in other words, when I make myself the object of reflec-
tion, I not only find that I am an incomplete, [imperfect] and de-t
pendent being, and one who unceasingly aspires after something
better and greater than he is ; but, at the same time, I am assured
likewise that he upon whom I am dependent possesses in himself
all the goods after which I aspire, [and the ideas of him which I find
in my mind], and that not merely indefinitely and potentially, but in-
finitely and actually, and that he is thus God. And the whole force
of the argument of which I have here availed myself to establish the
existence of God, consists in this, that I perceive I could not possibly
be of such a nature as I am, and yet have in my mind the idea of a
God, if God did not in reality exist, — this same God, I say, whose
idea is in my mind — that is, a being who possesses all those lofty
perfections, of which the mind may have some slight conception,
without, however, being able fully to comprehend them, — and who
is wholly superior to all defect, [and has nothing that marks imper-
fection] : whence it is sufficiently manifest that he cannot be a de-
ceiver, since it is a dictate of the natural light that all fraud and
deception spring from defect.
But before I examine this with more attention, and pass on to
the consideration of other truths that may be evolved out of it, I
think it proper to remain here for some time in the contemplation
of God himself — that I may ponder at leisure his marvellous attri-
butes— and behold, admire and adore the beauty of this light so
unspeakably great, as far, at least, as the strength of my mind,
which is to some degree dazzled by the sight, will permit. For just
as we learn by faith that the supreme felicity of another life consists
in the contemplation of the Divine majesty alone, so even now we
learn from experience that a like meditation, though incomparably
less perfect, is the source of the highest satisfaction of which we are
susceptible in this life.
MEDITATION IV.
OF TRUTH AND ERROR
TRUTH DEPENDENT ON GOD
I have been habituated these bygone days to detach my mind
from the senses, and I have accurately observed that there is ex-
ceedingly little which is known with certainty respecting corporeal
objects, — that we know much more of the human mind, and still
32 THE BEGINNING OF MODERN PHILOSOPHY
more of God Himself. I am thus able now without difficulty to ab-
stract my mind from the contemplation of [sensible or] imaginable
objects, and apply it to those which, as disengaged from all other
matter, are purely intelligible. And certainly the idea I have of the
human mind, in so far as it is a thinking thing, and not extended in
length, breadth, and depth, and participating in none of the prop-
erties of body, is incomparably more distinct than the idea of any
corporeal object; and when I consider that I doubt, in other words,
that I am an incomplete and dependent being, the idea of a com-
plete and independent being, that is to say of God, occurs to my
mind with so much distinctness and clearness, — and from the fact
alone that this idea is found in me, or that I who possess it exist,
the conclusions that God exists, and that my own existence, each
moment of its continuance, is absolutely dependent upon Him, are
so manifest, — as to lead me to believe it impossible that the human
mind can know anything with more clearness and certitude. And
now I seem to discover a path that will conduct us from the con-
templation of the true God, in whom are contained all the treasures
of science and wisdom, to the knowledge of the other things in the
universe.
For, in the first place, I discover that it is impossible for Him
ever to deceive me, for in all fraud and deceit there is a certain im-
perfection; and although it may seem that the ability to deceive is
a mark of subtlety or power, yet the will testifies without doubt of
malice and weakness ; and such, accordingly cannot be found in God.
In the next place, I am conscious that I possess a certain faculty
of judging [or discerning truth from error], which I doubtless re-
ceived from God, along with whatever else is mine ; and since it is
impossible that He should will to deceive me, it is likewise certain
that He has not given me a faculty that will ever lead me into error,
provided I use it aright.
And there would remain no doubt on this head, did it not seem
to follow from this, that I can never therefore be deceived ; for if all
I possess be from God, and if He planted in me no faculty that is
deceitful, it seems to follow that I can never fall into error. Accord-
ingly, it is true that when I think only of God (when I look upon my-
self as coming from God,) and turn wholly to Him, I discover
[in myself] no cause of error or falsity; but immediately thereafter,
recurring to myself, experience assures me that I am nevertheless
THE BEGINNING OF MODERN PHILOSOPHY 63
subject to innumerable errors. When I come to inquire into the
cause of these, I observe that there is not only present to my con-
sciousness a real and positive idea of God, or of a being supremely
perfect, but also, so to speak, a certain negative idea of nothing, —
in other words, of that which is at an infinite distance from every
sort of perfection, and that I am, as it were, a mean between God
and nothing, or placed in such a way between the absolute existence
and non-existence, that there is in truth nothing in me to lead me
into error, in so far as an absolute being is my creator ; but that, on
the other hand, as I thus likewise participate in some degree of noth-
ing or of non-being, in other words, as I am not myself the supreme
Being, and as I am wanting in many perfections, it is not surprising
I should fall into error. And I hence discern that error is not some-
thing real, which depends for its existence on God, but is simply
defect; and therefore that, in order to fall into it, it is not necessary
that God should have given me a faculty expressly for this end, but
that my being deceived arises from the circumstances that the power
which God has given me of discerning truth from error is not
infinite.
SPINOZA
BENEDICT SPINOZA was born of a Jewish family in Amsterdam
in the year 1632. He got his first schooling under Rabbi Morteira.
He also learned to polish lenses. Later he struck up a friendship
with Jorigh Jelles, an Anabaptist, and made something of a study
of Christianity. He became interested in the treasures of knowledge
enclosed in Latin and some of the modern languages, and grew to
be something of a linguist. The new physical sciences also inter-
ested him, and at last he was attracted by philosophy. His opinions
brought him into conflict with the Jewish community in which he
lived, and he was expelled from the synagogue.
The philosophy of the time was that of Descartes. This looked
at the material world as purely mechanical, and placed an absolute
gulf, bridged only by God, between matter and mind. Spinoza
64 THE BEGINNING OF MODERN PHILOSOPHY
gradually came to look back of this dualism, and to consider God
or Nature the only true reality and all else but manifestations of
this. Matter and mind are two attributes of God. They are always
found together, not interacting, but parallel, two expressions of the
same truth.
All his life was passed in Holland, and was mostly a solitary
existence, occupied in his lens-polishing, his meditations and his
correspondence. He became a man of prominence, and was offered
(1673) a professorship but declined it. He died February 21, 1677.
THE ETHICS
PART I. CONCERNING GOD
DEFINITIONS
I. By that which is self-caused, I mean that of which the es-
sence involves existence, or that of which the nature is only conceiv-
able as existent.
II. A thing is called finite after its kind, when it can be limited
by another thing of the same nature ; for instance, a body is called
finite because we always conceive another greater body. So, also,
a thought is limited by another thought, but a body is not limited
by thought, nor a thought by body.
III. By substance, I mean that which is in itself, and is con-
ceived through itself; in other words, that of which a conception
can be formed independently of any other conception.
IV. By attribute, I mean that which the intellect perceives as
constituting the essence of substance.
V. By mode, I mean the modifications of substance, or that
which exists in, and is perceived through, something other than
itself.
VI. By God, I mean a being absolutely infinite — that is, a sub-
stance consisting in infinite attributes, of which each expresses eter-
nal and infinite essentiality.
Explanation. — I say absolutely infinite, not infinite after its kind;
for, of a thing infinite only after its kind, infinite attributes may be
denied ; but that which is absolutely infinite, contains in its essence
whatever expresses reality, and involves no negation.
VII. That thing is called free, which exists solely by the
THE BEGINNING OF MODERN PHILOSOPHY 65
necessity of its own nature, and of which the action is determined
by itself alone. On the other hand, that thing is necessary, or rather
constrained, which is determined by something external to itself to
a fixed and definite method of existence or action.
VIII. By eternity, I mean existence itself, in so far as it is
conceived necessarily to follow solely from the definition of that
which is eternal.
Explanation. — Existence of this kind is conceived as an eternal
truth, like the essence of a thing, and, therefore, cannot be explained
by means of continuance or time, though continuance may be con-
ceived without a beginning or end.
AXIOMS
I. Everything which exists, exists either in itself or in some-
thing else.
II. That which cannot be conceived through anything else
must be conceived through itself.
III. From a given definite cause an effect necessarily follows ;
and, on the other hand, if no definite cause be granted, it is impos-
sible that an effect can follow.
IV. The knowledge of an effect depends on and involves the
knowledge of a cause.
V. Things which have nothing in common cannot be under-
stood, the one by means of the other; the conception of one does
not involve the conception of the other.
VI. A true idea must correspond with its ideate or object.
VII. If a thing can be conceived as non-existing, its essence
does not involve existence.
PROPOSITIONS
Prop. I. Substance is by nature prior to its modifications.
Proof. — This is clear from Def. iii. and v.
Prop. II. Two substances, whose attributes are different, have
nothing in common.
Proof. — Also evident from Def. iii. For each must exist in
itself, and be conceived through itself; in other words, the con-
ception of one does not imply the conception of the other.
Prop. III. Things which have nothing in common cannot be
one the cause of the other.
66 THE BEGINNING OF MODERN PHILOSOPHY
Proof. — If they have nothing in common, it follows that one
cannot be apprehended by means of the other (Ax. v.), and, there-
fore, one cannot be the cause of the other (Ax. iv.) Q. E. D.
Prop. IV. Two or more distinct things are distinguished one
from the other, either by the difference of the attributes of the sub-
stances, or by the difference of their modifications.
Proof. — Everything which exists, exists either in itself or in
something else (Ax. i.), — that is (by Def. iii. and v.), nothing is
granted in addition to the understanding, except substance and its
modifications. Nothing is, therefore, given besides the understand-
ing, by which several things may be distinguished one from the
other, except the substances, or, in other words (see Ax. iv.), their
attributes and modifications. Q. E. D.
Prop. V. There cannot exist in the universe two or more sub-
stances having the same nature or attribute.
Proof. — If several distinct substances be granted, they must be
distinguished one from the other, either by the difference of their
attributes, or by the difference of their modifications (Prop. iv.). If
only by the difference of their attributes it will be granted that
there cannot be more than one, with an identical attribute. If
by the difference of their modifications — as substance is nat-
urally prior to its modifications (Prop, i.), — it follows that setting
the modifications aside, and considering substance in itself, that is,
truly (Def. iii. and vi.), there cannot be conceived one substance
different from another, — that is (by Prop, iv.), there cannot be
granted several substances, but one substance only. Q. E. D.
Prop. VI. One substance cannot be produced by another sub-
stance.
Proof. — It is impossible that there should be in the universe two
substances with an identical attribute, i. e., which have anything
common to them both (Prop, ii.), and, therefore (Prop, iii.), one
cannot be the cause of another, neither can one be produced by the
other. Q. E. D.
Corollary. — Hence it follows that a substance cannot be pro-
duced by anything external to itself. For in the universe nothing is
granted, save substances and their modifications (as appears from
Ax. i. and Def. iii. and v.). Now (by the last Prop.) substance can-
not be produced by another substance, therefore it cannot be pro-
duced by anything external to itself. Q. E. D. This is shown still
THE BEGINNING OF MODERN PHILOSOPHY 67
more readily by the absurdity of the contradictory. For, if sub-
stance be produced by an external cause, the knowledge of it would
depend on the knowledge of its cause (Ax. iv.), and (by Def. iii.)
it would itself not be substance.
Prop. VII. Existence belongs to the nature of substance.
Proof. — Substance cannot be produced by anything external
(Corollary, Prop, vi.), it must, therefore, be its own cause — that is,
its essence necessarily involves existence, or existence belongs to
its nature.
Prop. VIII. Every substance is necessarily infinite.
Proof. — There can only be one substance with an identical at-
tribute, and existence follows from its nature (Prop, vii.) ; its na-
ture, therefore, involves existence, either as finite or infinite. It does
not exist as finite, for (by Def. ii.) it would then be limited by some-
thing else of the same kind, which would also necessarily exist
(Prop, vii.) ; and there would be two substances with an identical
attribute, which is absurd (Prop. vi.). It therefore exists as infinite.
Q. E. D.
Note I. — As finite existence involves a partial negation, and in-
finite existence is the absolute affirmation of the given nature, it fol-
lows (solely from Prop, vii.) that every substance is necessarily
infinite.
Note II. — No doubt it will be difficult for those who think about
things loosely, and have not been accustomed to know them by their
primary causes, to comprehend the demonstration of Prop. vii. : for
such persons make no distinction between the modifications of sub-
stances and the substances themselves, and are ignorant of the man-
ner in which things are produced ; hence they attribute to substances
the beginning which they observe in natural objects. Those who
are ignorant of true causes, make complete confusion — think that
trees might talk just as well as men — that men might be formed
from stones as well as from seed ; and imagine that any form might
be changed into any other. So, also, those who confuse the two
natures, divine and human, readily attribute human passions to the
Deity, especially so long as they do not know how passions originate
in the mind. But, if people would consider the nature of substance,
they would have no doubt about the truth of Prop. vii. In fact,
this proposition would be a universal axiom, and accounted a truism.
For, by substance, would be understood that which is in itself, and
68 THE BEGINNING OF MODERN PHILOSOPHY
is conceived through itself — that is, something of which the con-
ception requires not the conception of anything else ; whereas modi-
fications exist in something external to themselves, and a conception
of them is formed by means of a conception of the thing in
which they exist. Therefore, we may have true ideas of non-
existent modifications; for, although they may have no ac-
tual existence apart from the conceiving intellect, yet their
essence is so involved in something external to themselves that they
may through it be conceived. Whereas the only truth substances
can have, external to the intellect, must consist in their existence,
because they are conceived through themselves. Therefore, for a
person to say that he has a clear and distinct — that is, a true — idea
of a substance, but that he is not sure whether such substance exists,
would be the same as if he said that he had a true idea, but was
not sure whether or no it was false (a little consideration will make
this plain) ; or if anyone affirmed that substance is created, it would
be the same as saying that a false idea was true — in short, the height
of absurdity. It must, then, necessarily be admitted that the exist-
ence of substance as its essence is an eternal truth. And we can
hence conclude by another process of reasoning — that there is but
one such substance. I think that this may profitably be done at
once ; and, in order to proceed regularly with the demonstration, we
must premise: —
1. The true definition of a thing neither involves nor expresses
anything beyond the nature of the thing defined. From this it fol-
lows that —
2. No definition implies or expresses a certain number of in-
dividuals, inasmuch as it expresses nothing beyond the nature of the
thing defined. For instance, the definition of a triangle expresses
nothing beyond the actual nature of a triangle: it does not imply
any fixed number of triangles.
3. There is necessarily for each individual existent thing a
cause why it should exist.
4. This cause of existence must either be contained in the
nature and definition of the thing defined, or must be postulated
apart from such definition.
It therefore follows that, if a given number of individual things
exist in nature, there must be some cause for the existence of exactly
that number, neither more nor less. For example, if twenty men
THE BEGINNING OF MODERN PHILOSOPHY 69
exist in the universe (for simplicity's sake, I will suppose them ex-
isting simultaneously, and to have had no predecessors), and we
want to account for the existence of these twenty men, it will not
be enough to show the cause of human existence in general; we
must also show why there are exactly twenty men, neither more
nor less : for a cause must be assigned for the existence of each in-
dividual. Now this cause cannot be contained in the actual nature
of man, for the true definition of man does not involve any consid-
eration of the number twenty. Consequently, the cause for the ex-
istence of these twenty men, and, consequently, of each of them,
must necessarily be sought externally to each individual. Hence
we may lay down the absolute rule, that everything which may con-
sist of several individuals must have an external cause. And, as it
has been shown already that existence appertains to the nature of
substance, existence must necessarily be included in its definition ;
and from its definition alone existence must be deductible. But
from its definition (as we have shown, Notes ii., Hi.), we cannot
infer the existence of several substances; therefore it follows that
there is only one substance of the same nature. Q. E. D.
Prop. IX. The more reality or being a thing has the greater
the number of its attributes (Def. iv.).
Prop. X. Each particular attribute of the one substance must
be conceived through itself.
Proof. — An attribute is that which the intellect perceives of sub-
stance, as though constituting its essence (Def. iv.), and, therefore,
must be conceived through itself (Def. iii.). Q. E. D.
Note. — It is thus evident that, though two attributes are, in
fact, conceived as distinct — that is, one without the help of the
other — yet we cannot, therefore, conclude that they constitute two
entities, or two different substances. For it is the nature of sub-
stance that each of its attributes is conceived through itself, inas-
much as all the attributes it has have always existed simultaneously
in it, and none could be produced by any other ; but each expresses
the reality or being of substance. It is, then, far from an absurdity
to ascribe several attributes to one substance : for nothing in nature
is more clear than that each and every entity must be conceived
under some attribute, and that its reality or being is in proportion
tc the number of its attributes expressing necessity or eternity and
infinity. Consequently it is abundantly clear, than an absolutely in-
70 THE BEGINNING OF MODERN PHILOSOPHY
finite being must necessarily be defined as consisting in infinite
attributes, each of which expresses a certain eternal and infinite
essence.
If anyone now ask, by what sign shall he be able to distinguish
different substances, let him read the following propositions, which
show that there is but one substance in the universe, and that it is
absolutely infinite, wherefore such a sign would be sought for in
vain.
Prop. XI. God, or substance, consisting of infinite attributes,
of which each expresses eternal and infinite essentiality, necessarily
exists.
Proof. — If this be denied, conceive, if possible, that God does
not exist: then his essence does not involve existence. But this
(by Prop, vii.) is absurd. Therefore God necessarily exists.
Another Proof. — Of everything whatsoever a cause or reason
must be assigned, either for its existence, or for its non-existence —
e. g., if a triangle exist, a reason or cause must be granted for its
existence; if, on the contrary, it does not exist, a cause must also
be granted, which prevents it from existing, or annuls its existence.
This reason or cause must either be contained in the nature of the
thing in question, or be external to it. For instance, the reason for
the non-existence of a square circle is indicated in its nature, namely,
because it would involve a contradiction. On the other hand, the
existence of substance follows also solely from its nature, inasmuch
as its nature involves existence. (See Prop, vii.)
But the reason for the existence of a triangle or a circle does
not follow from the nature of those figures, but from the order of
universal nature in extension. From the latter it must follow, either
that a triangle necessarily exists, or that it is impossible that it
should exist. So much is self-evident. It follows therefrom that a
thing necessarily exists, if no cause or reason be granted which pre-
vents its existence.
If, then, no cause or reason can be given, which prevents the
existence of God, or which destroys his existence, we must certainly
conclude that he necessarily does exist. If such a reason or cause
should be given, it must either be drawn from the very nature of
God, or be external to him — that is, drawn from another substance
of another nature. For if it were of the same nature, God, by that
very fact, would be admitted to exist. But substance of another na-
THE BEGINNING OF MODERN PHILOSOPHY 71
ture could have nothing in common with God (by Prop, ii.), and
therefore would be unable either to cause or to destroy his existence.
As, then, a reason or cause which would annul the divine exist-
ence cannot be drawn from anything external to the divine nature,
such cause must perforce, if God does not exist, be drawn from God's
own nature, which would involve a contradiction. To make such
an affirmation about a being absolutely infinite and supremely per-
fect, is absurd ; therefore, neither in the nature of God, nor externally
to his nature, can a cause or reason be assigned which would annul
his existence. Therefore, God necessarily exists. Q. E. D.
Another Proof. — The potentiality of non-existence is a negation
of power, and contrariwise the potentiality of existence is a power,
as is obvious. If, then, that which necessarily exists is nothing but
finite beings, such finite beings are more powerful than a being abso-
lutely infinite, which is obviously absurd ; therefore, either nothing
exists, or else a being absolutely infinite necessarily exists also. Now
we exist either in ourselves, or in something else which necessarily
exists (see Axiom i. and Prop. vii.). Therefore a being absolutely
infinite — in other words, God (Def. vi.) — necessarily exists. Q. E. D.
Note. — In this last proof, I have purposely shown God's exist-
ence a posteriori, so that the proof might be more easily followed, not
because, from the same premises, God's existence does not follow
a priori. For, as the potentiality of existence is a power, it follows
that, in proportion as reality increases in the nature of a thing, so
also will it increase its strength for existence. Therefore a being
absolutely infinite, such as God, has from himself an absolutely in-
finite power of existence, and hence he does absolutely exist. Per-
haps there will be many who will be unable to see the force of this
proof, inasmuch as they are accustomed only to consider those
things which flow from external causes. Of such things, they see
that those which quickly come to pass — that is, quickly come into
existence — quickly also disappear ; whereas they regard as more dif-
ficult of accomplishment — that is, not so easily brought into exist-
ence— those things which they conceive as more complicated.
However, to do away with this misconception, I need not here
show the measure of truth in the proverb, "What comes quickly,
goes quickly," nor discuss whether, from the point of view of uni-
versal nature, all things are equally easy, or otherwise: I need only
72 TEE BEGINNING OF MODERN PHILOSOPHY
remark, that I am not here speaking of things, which come to pass
through causes external to themselves, but only of substances which
(by Prop, vi.) cannot be produced by any external cause. Things
which are produced by external causes whether they consist of many
parts or few, owe whatsoever perfection or reality they possess
solely to the efficacy of their external cause, and therefore their
existence arises solely from the perfection of their external cause,
not from their own. Contrariwise, whatsoever perfection is pos-
sessed by substance is due to no external cause; wherefore the
existence of substance must arise solely from its own nature, which
is nothing else but its essentiality. Thus, the perfection of a thing
does not annul its existence, but, on the contrary, asserts it. Imper-
fection, on the other hand, does annul it; therefore we cannot be
more certain of the existence of anything, than of the existence of a
being absolutely infinite or perfect — that is, of God. For inasmuch
as his essence excludes all imperfection, and involves absolute per-
fection, all cause for doubt concerning his existence is done away,
and the utmost certainty on the question is given. This, I think,
will be evident to every moderately attentive reader.
AGAINST MISCONCEPTIONS OF GOD'S NATURE
APPENDIX. — In the foregoing I have explained the nature and
properties of God. I have shown that he necessarily exists, that he
is one : that he is, and acts solely by the necessity of his own nature ;
that he is the free cause of all things, and how he is so; that all
things are in God, and so depend on him, that without him they
could neither exist nor be conceived ; lastly, that all things are pre-
determined by God, not through his free will or absolute fiat, but
from the very nature of God or infinite power. I have further,
where occasion offered, taken care to remove the prejudices, which
might impede the comprehension of my demonstrations. Yet there
still remain misconceptions not a few, which might and may prove
very grave hindrances to the understanding of the concatenation of
things, as I have explained it above. I have therefore thought it
worth while to bring these misconceptions before the bar of reason.
All such opinions spring from the notion commonly entertained,
that all things in nature act as men themselves act, namely, with an
end in view. It is accepted as certain, that God himself directs all
things to a definite goal (for it is said that God made all things for
THE BEGINNING OF MODERN PHILOSOPHY 73
man, and man that he might worship Him). I will, therefore, con-
sider this opinion, asking first, why it obtains general credence, and
why all men are naturally so prone to adopt it ? secondly, I will point
out its falsity ; and, lastly, I will show how it has given rise to preju-
dices about good and bad, right and wrong, praise and blame, order
and confusion, beauty and ugliness, and the like. However, this is
not the place to deduce these misconceptions from the nature of the
human mind : it will be sufficient here, if I assume as a starting point,
what ought to be universally admitted, namely, that all men are
born ignorant of the causes of things, that all have the desire to seek
for what is useful to them, and that they are conscious of such de-
sire. Herefrom it follows, first, that men think themselves free inas-
much as they are conscious of their volitions and desires, and never
even dream, in their ignorance, of the causes which have disposed
them so to wish and desire; secondly, that men do all things for an
end, namely, for that which is useful to them, and which they seek.
Thus it comes to pass that they only look for a knowledge of the
final causes of events, and when these are learned, they are content,
as having no cause for further doubt. If they cannot learn such
causes from external sources, they are compelled to turn to consid-
ering themselves, and reflecting what end would have induced them
personally to bring about the given event, and thus they necessarily
judge other natures by their own. Further, as they find in them-
selves and outside themselves many means which assist them not
a little in their search for what is useful, for instance, eyes for see-
ing, teeth for chewing, herbs and animals for yielding food, the sun
for giving light, the sea for breeding fish, &c., they come to look on
the whole of nature as a means for obtaining such conveniences.
Now as they are aware, that they found these conveniences and did
not make them, they think they have cause for believing, that some
other being has made them for their use. As they look upon things
as means, they cannot believe them to be self-created ; but, judging
from the means which they are accustomed to prepare for them-
selves, they are bound to believe in some ruler or rulers of the
universe endowed with human freedom, who have arranged and
adapted everything for human use. They are bound to estimate the
nature of such rulers (having no information on the subject) in ac-
cordance with their own nature, and therefore they assert that the
gods ordained everything for the use of man, in order to bind man
V 6-5
74 THE BEGINNING OF MODERN PHILOSOPHY
to themselves and obtain from him the highest honour. Hence also
it follows, that everyone thought out for himself, according to his
abilities, a different way of worshipping God, so that God might
love him more than his fellows, and direct the whole course of na-
ture for the satisfaction of his blind cupidity and insatiable avarice.
Thus the prejudice developed into superstition, and took deep root
in the human mind ; and for this reason everyone strove most zeal-
ously to understand and explain the final causes of things ; but in
their endeavour to show that nature does nothing in vain, i. e.,
nothing which is useless to man, they only seem to have demon-
strated that nature, the gods, and men are all mad together. Con-
sider, I pray you, the result : among the many helps of nature they
were bound to find some hindrances, such as storms, earthquakes,
diseases, &c. : so they declared that such things happen, because
the gods are angry at some wrong done them by men, or at some
fault committed in their worship. Experience day by day pro-
tested and showed by infinite examples, that good and evil fortunes
fall to the lot of pious and impious alike; still they would not
abandon their inveterate prejudice, for it was more easy for them to
class such contradictions among other unknown things of whose
use they were ignorant, and thus to retain their actual and innate
condition of ignorance, than to destroy the whole fabric of their
reasoning and start afresh. They therefore laid down as an axiom,
that God's judgments far transcend human understanding. Such a
doctrine might well have sufficed to conceal the truth from the
human race for all eternity, if mathematics had not furnished an-
other standard of verity in considering solely the essence and prop-
erties of figures without regard to their final causes. There are
other reasons (which I need not mention here) besides mathematics,
which might have caused men's minds to be directed to these gen-
eral prejudices, and have led them to the knowledge of the truth.
I have now sufficiently explained my first point. There is no
need to show at length, that nature has no particular goal in view,
and that final causes are mere human figments. This, I think, is
already evident enough, both from the causes and foundations on
which I have shown such prejudice to be based, and also from Prop,
xvi., and the Corollary of Prop, xxxii., and, in fact, all those proposi-
tions in which I have shown, that everything in nature proceeds
from a sort of necessity, and with the utmost perfection. However,
THE BEGINNING OF MODERN PHILOSOPHY 75
I will add a few remarks, in order to overthrow this doctrine of a
final cause utterly. That which is really a cause it considers as an
effect, and vice versa: it makes that which is by nature first to be
last, and that which is highest and most perfect to be most imper-
fect. Passing over the questions of cause and priority as self-evi-
dent, it is plain from Props, xxi., xxii., xxiii. that that effect is most
perfect which is produced immediately by God; the effect which
requires for its production several intermediate causes is, in that
respect, more imperfect. But if those things which were made im-
mediately by God were made to enable him to attain his end, then
the things which come after, for the sake of which the first were
made, are necessarily the most excellent of all.
Further, this doctrine does away with the perfection of God:
for, if God acts for an object, he necessarily desires something which
he lacks. Certainly, theologians and metaphysicians draw a distinc-
tion between the object of want and the object of assimilation ; still
they confess that God made all things for the sake of himself, not
for the sake of creation. They are unable to point to anything
prior to creation, except God himself, as an object for which God
should act, and are therefore driven to admit (as they clearly must),
that God lacked those things for whose attainment he created
means, and further that he desired them.
We must not omit to notice that the followers of this doctrine,
anxious to display their talent in assigning final causes, have im-
ported a new method of argument in proof of their theory — namely,
a reduction, not to the impossible, but to ignorance ; thus showing
that they have no other method of exhibiting their doctrine. For
example, if a stone falls from a roof on to someone's head, and kills
him, they will demonstrate by their new method, that the stone fell
in order to kill the man ; for, if it had not by God's will fallen with
that object, how could so many circumstances (and there are often
many concurrent circumstances) have all happened together by
chance ? Perhaps you will answer that the event is due to the facts
that the wind was blowing, and the man was walking that way.
"But why," they will insist, "was the wind blowing, and why was the
man at that very time walking that way?" If you again answer,
that the wind had then sprung up because the sea had begun to be
agitated the day before, the weather being previously calm, and
that the man had been invited by a friend, they will again insist:
76 THE BEGINNING OF MODERN PHILOSOPHY
"But why was the sea agitated, and why was the man invited at that
time ?" So they will pursue their questions from cause to cause, till
at last you take refuge in the will of God — in other words, the sanc-
tuary of ignorance. So, again, when they survey the frame of the
human body, they are amazed ; and being ignorant of the causes of
so great a work of art, conclude that it has been fashioned, not me-
chanically, but by divine and supernatural skill, and has been so
put together that one part shall not hurt another.
Hence anyone who seeks for the true causes of miracles, and
strives to understand natural phenomena as an intelligent being, and
not to gaze at them like a fool, is set down and denounced as an
impious heretic by those, whom the masses adore as the interpreters
of nature and the gods. Such persons know that, with the removal
of ignorance, the wonder which forms their only available means for
proving and preserving their authority would vanish also. But I
now quit this subject, and pass on to my third point.
After men persuaded themselves, that everything which is cre-
ated is created for their sake, they were bound to consider as the
chief quality in everything that which is most useful to themselves,
and to account those things the best of all which have the most bene-
ficial effect on mankind. Further, they were bound to form abstract
notions for the explanation of the nature of things, such as goodness,
badness, order, confusion, warmth, cold, beauty, deformity, and so
on; and from the belief that they are free agents arose the further
notions praise and blame, sin and merit.
I w>ll speak of these latter hereafter, when I treat of human
nature ; the former I will briefly explain here.
Everything which conduces to health and the worship of God
they have called good, everything which hinders these objects they
have styled bad; and inasmuch as those who do not understand the
nature of things do not verify phenomena in any way, but merely
imagine them after a fashion, and mistake their imagination for
understanding, such persons firmly believe that there is an order in
things, being really ignorant both of things and their own nature.
When phenomena are of such a kind, that the impression they make
on our senses requires little effort of imagination, and can conse-
quently be easily remembered, we say that they are well-ordered;
if the contrary, that they are ill-ordered or confused. Further, as
things which are easily imagined are more pleasing to us, men pre-
THE BEGINNING OF MODERN PHILOSOPHY 77
fer order to confusion — as though there were any order in nature,
except in relation to our imagination — and say that God has created
all things in order; thus, without knowing it, attributing imagina-
tion to God, unless, indeed, they would have it that God foresaw
human imagination, and arranged everything, so that it should be
most easily imagined. If this be their theory, they would not, per-
haps, be daunted by the fact that we find an infinite number of phe-
nomena, far surpassing our imagination, and very many others
which confound its weakness. But enough has been said on this
subject. The other abstract notions are nothing but modes of im-
agining in which the imagination is differently affected, though they
are considered by the ignorant as the chief attributes of things, inas-
much as they believe that everything was created for the sake of
themselves ; and, according as they are affected by it, style it good
or bad, healthy or rotten and corrupt. For instance, if the motion
which objects we see communicate to our nerves be conducive to
health, the objects causing it are styled beautiful ; if a contrary mo-
tion be excited, they are styled ugly.
Things which are perceived through our sense of smell are
styled fragrant or fetid ; if through our taste, sweet or bitter, full-
flavoured or insipid ; if through our touch, hard or soft, rough or
smooth, &c.
Whatsoever affects our ears is said to give rise to noise, sound,
or harmony. In this last case, there are men lunatic enough to
believe, that even God himself takes pleasure in harmony ; and phil-
osophers are not lacking who have persuaded themselves, that the
motion of the heavenly bodies gives rise to harmony — all of which
instances sufficiently show that everyone judges of things according
to the state of his brain, or rather mistakes for things the forms of
his imagination. We need no longer wonder that there have arisen
all the controversies we have witnessed, and finally scepticism : for,
although human bodies in many respects agree, yet in very many
other they differ; so that what seems good to one seems bad
to another; what seems ordered to one seems confused to an-
other; what is pleasing to one displeases another, and so on. I
need not further enumerate, because this is not the place to treat
the subject at length, and also because the fact is sufficiently well
known. It is commonly said : "So many men, so many minds ;
everyone is wise in his own way; brains differ as completely as pal-
78 THE BEGINNING OF MODERN PHILOSOPHY
ates." All of which proverbs show, that men judge of things accord-
ing to their mental disposition, and rather imagine than understand :
for, if they understood phenomena, they would, as mathematics
attest, be convinced, if not attracted, by what I have urged.
We have now perceived, that all the explanations commonly
given of nature are mere modes of imagining, and do not indicate
the true nature of anything, but only the constitution of the imagina-
tion ; and, although they have names, as though they were entities,
existing externally to the imagination, I call them entities imagin-
ary rather than real ; and, therefore, all arguments against us drawn
from such abstractions are easily rebutted.
Many argue in this way. If all things follow from a necessity
of the absolutely perfect nature of God, why are there so many im-
perfections in nature? such, for instance, as things corrupt to the
point of putridity, loathsome deformity, confusion, evil, sin, &c.
But these reasoners are, as I have said, easily confuted, for the per-
fection of things is to be reckoned only from their own nature and
power; things are not more or less perfect, according as they delight
or offend human senses, or according as they are serviceable or re-
pugnant to mankind. To those who ask why God did not so create
all men, that they should be governed only by reason, I give no
answer but this: because matter was not lacking to him for the
creation of every degree of perfection from highest to lowest; or,
more strictly, because the laws of his nature are so vast, as to suf-
fice for the production of everything conceivable by an infinite intel-
ligence, as I have shown in Prop. xvi.
Such are the misconceptions I have undertaken to note ; if there
are any more of the same sort, everyone may easily dissipate them
for himself with the aid of a little reflection.
LEIBNITZ
GOTTFRIED WILHELM LEIBNITZ was born June 21 [old style],
1646. His father was the actuary of the University of Leipzig. He
was a very precocious child, for example, learning Latin at eight
THE BEGINNING OF MODERN PHILOSOPHY 79
years of age without the use of a grammar by reading and rereading
Livy. He entered the university of his home town at fifteen and
paid particular attention to law. He was refused a doctor's degree
in law at Leipzig on account of his age, but obtained it at Altorf,
and was offered a professorship there, but refused it.
In 1668 he published his "New Method of Learning and Teach-
ing Jurisprudence," which aroused considerable interest. He became
active in politics and tried to find a ground for the reconcilation of
Catholicism and Protestantism. Huyghens initiated him into higher
mathematics, and soon afterwards, Leibnitz invented the Differen-
tial Calculus.
He was for some time councillor and a member of the supreme
court of Brunswick-Liineburg, and became a friend of a number of
the princes of the continent.
In 1714 he wrote his "Monadology." This sought to get back
of the Cartesian dualism of mind and matter by spiritualizing the
conception of the atom and making each monad, so-called, an indi-
viduality. To the lowest order he assigned merely action as in the
crystal ; to a higher, life and unconscious thought as in the plant ;
to the next higher, conscious thought as in the animal ; to the high-
est, self-consciousness. The supreme monad in such a scheme would
be God. The harmony between them he thought to be pre-estab-
lished by God. Many of his ideas are embodied in the present day
conception of the cell, and such a conception of the universe is cer-
tainly as possible logically as is the conception of the physical world
being built up of atoms.
He died November 14, 1716.
THE MONADOLOGY
1. The monad, of which we shall here speak, is merely a simple
substance, that enters into compounds; simple, that is to say, with-
out parts.
2. And there must be simple substances, since there are com-
pound substances, for the compound is only a collection or aggrega-
tion of the simple.
3. Now where there are no parts, neither extension, nor figure,
nor divisibility is possible. And these monads are the true atoms of
nature, and, in a word, the elements of things.
60 THE BEGINNING OF MODERN PHILOSOPHY
4. Destruction also is not to be feared, and there is no conceiv-
able way in which a simple substance can perish naturally.
5. For the same reason there is no way in which a simple sub-
stance can begin naturally, since it cannot be formed by composition.
6. Hence it may be said that the monads can begin or end
only all at once, that is to say, they can begin only by creation and
end by annihilation ; whereas what is compound begins or ends by
parts.
7. There is also no evident way how a monad can be altered
or changed internally by any other creature, for nothing can be
transposed within it, nor can there be conceived in it any internal
movement that can be excited, directed, augmented or diminished
within it, as can be done in compounds, where there is change among
the parts. The monads have no windows through which anything
can enter or depart. Accidents cannot detach themselves or go forth
from the substances, as formerly the sensible species of the School-
men. And neither substance nor accident can enter a monad from
without.
8. Nevertheless, the monads must have some qualities, other-
wise they would not even be entities. And if simple substances did
not differ at all in their qualities there would be no way whereby we
could perceive any changes in things, since what is in the compound
can only come from the simple ingredients, and if the monads were
without qualities they could not be distinguished from one another,
since also they do not differ in quantity. Consequently, a plenum
being supposed, each place in any change of parts could receive only
the same as what it had had before, and one state of things would
not be distinguishable from another.
9. Moreover each monad must differ from every other. For in
nature two beings are never exactly alike and such that it is not
possible to find an internal difference or one founded upon an in-
trinsic analysis.
10. I take it for granted also that every created being, and con-
sequently the created monad also, is subject to change, and also that
this change is continual in each.
11. It follows from what has just been said, that the natural
changes of the monads proceed from an internal principle, since an
external cause cannot influence their interior.
12. But besides the principle of change, there must be particu-
THE BEGINNING OF MODERN PHILOSOPHY 81
lar changes in what changes, which forms, so to speak, the speci-
fication and variety of the simple substances.
13. This detail must involve multitude in unity or in the sim-
ple. For since every natural change is made by degrees, something
changes and something remains ; consequently, there must be in
the simple substance a plurality of affections and of relations, al-
though not of parts.
14. This transient state, which involves and represents multi-
tude in unity or in the simple substance, is only what we call per-
ception, which must be distinguished from apperception or from
consciousness, as will appear in what follows. Here it is that the
Cartesians especially failed, who made no account of the perceptions
of which we are not conscious. It is this also which made them sup-
pose that only spirits are monads and that there are no souls in
brutes or of other entities. They, with the vulgar, have also con-
founded a protracted state of unconsciousness with death, strictly
speaking, and have therefore admitted the old scholastic prejudice
of entirely separate souls, and have even confirmed weaker minds
in their belief of the mortality of the soul.
15. The action of the internal principle which causes the change
of the passage from one perception to another, may be called appeti-
tion ; it is true that this desire cannot always completely reach the
whole perception toward which it tends, but it always attains to
something of it and comes to new perceptions.
16. We experience in ourselves a case of multitude in a simple
substance, when we find that the most trifling thought of which we
are conscious involves variety in the object. Thus all who admit
that the soul is a simple substance must also admit this multitude
in the monad, and M. Bayle ought not to find in it the difficulties he
mentions in his Dictionary, article Rorarius.
17. We must confess, moreover, that perception and what de-
pends on it are inexplicable from mechanical causes, that is, by
figures and motions. Supposing that there were a machine so con-
structed as to cause thought, feeling and perception, we could con-
ceive of it enlarged and yet preserving the same proportions, so that
we might enter it like a mill. And this granted, we should only
find on visiting it, parts which push against one another, but never
anything by which to explain a perception. It must be sought for,
therefore, in the simple substance and not in the compound or ma-
82 THE BEGINNING OF MODERN PHILOSOPHY
chine. Nothing but this, also, can be found in the simple substance ;
and it is in this alone that all the internal actions of simple substances
consist.
18. The name of entelechies (entities) might be given to all sim-
ple substances or created monads, for they have within themselves
a certain perfection ; there is a certain sufficiency which renders them
the sources of their internal actions, and so to speak, incorporeal
automata.
19. If we care to give the name soul to everything that has
perceptions and desires in the general sense which I have just. ex-
plained, all simple substances or created monads may be called souls,
but as feeling is something more than a simple perception, I am will-
ing that the general name of monads or entelechies shall suffice for
those simple substances which have only perception, and that only
those substances shall be called souls whose perception is more dis-
tinct and is accompanied by memory.
20. For we experience in ourselves a state in which we remem-
ber nothing and have no distinguishable perceptions, as, for in-
stance, when we fall in a swoon or when we are overpowered by a
profound and dreamless sleep. In this state the soul does not differ
sensibly from a simple monad ; but as this state is not continuous
and as the soul frees itself from it, it is something more than a simple
monad.
21. Yet it does not all follow that therefore the simple sub-
stance is without any perception. This is indeed impossible, for the
reasons mentioned above ; for it cannot perish, nor can it exist with-
out some affection, which is nothing else than perception ; but when
there is a great number of minute perceptions, where nothing is
distinct, we are stunned, as when we turn round and round in the
same direction many times, whence arises a dizziness which may
make us lose consciousness, and which does not allow us to see any-
thing distinctly. So death may for a time produce this condition in
animals.
22. And as the present state of every simple substance is the nat-
ural consequence of its preceding state, so its present is big with its
future.
23. Therefore, since on being awakened from a stupor, we are
aware of our perceptions, we must have had them immediately before
although we were entirely unconscious of them ; for one perception can
THE BEGINNING OF MODERN PHILOSOPHY 83
come naturally only from another perception as one motion can come
naturally only from another motion.
24. From this we see that if there were nothing distinct, nothing,
as may be said, in relief or of a higher flavor, in our perceptions, we
should always be in a dazed state. This is a condition of the naked
monad.
25. Thus we see that nature has given to animals higher percep-
tions, by the care she has taken to furnish them with organs which col-
lect many rays of light or many undulations of air, in order to render
them more powerful by their union. There is something of the same
kind in odor, in taste, in touch and perhaps in a multitude of other senses
which are unknown to us. I shall presently explain how what takes
place in the soul represents what occurs in the organs.
26. Memory gives the souls a sort of consecutiveness which is like
reason, but which ought to be distinguished from it. We observe that
animals, seeing something which may strike them and of which they
have had a similar perception before, expect, through their memory,
what was associated with it in the preceding perception, and experience
feelings similar to those which they had at that time. For instance,
if we show dogs the cane, they remember the pain it has caused them
and whine and run.
27. And the powerful imagination which strikes and moves them,
arises either from the magnitude or the multitude of preceding percep-
tions. For often a strong impression produces all at once the same effect
as a long continued habit, or as many repeated moderate perceptions.
28. Men are like the brutes in so far as the consecutiveness of their
perceptions only results from the principle of memory, resembling the
empirical physicians who practice without theory, and we are mere em-
pirics in three-fourths of our actions. For example, when we expect
that there will be daylight to-morrow, we are acting as empirics, because
this has always taken place. It is only the astronomer who expects it
from grounds of reason.
29. The knowledge of necessary and eternal truths is what distin-
guishes us from mere animals and gives us reason and the sciences, by
raising us to a knowledge of ourselves and of God. This is what we
call the reasonable soul or spirit within us.
30. It is also by this knowledge of necessary truths, and their ab-
stractions, that we rise to acts of reflection, which make us think of that
which calls itself " I," and consider that this or that is within us ; and it
84 THE BEGINNING OF MODERN PHILOSOPHY
is thus that, in thinking of ourselves, we think of being, of substance,
simple or compound, of the immaterial and of God Himself, conceiving
that what with us is limited is with Him unlimited. These reflective acts
constitute the principal objects of our reasonings.
31. Our reasonings are founded on two great principles, that of
contradiction, by virtue of which we judge that to be false which in-
volves self-contradiction and that true, which is opposed or contradic-
tory to the false.
32. And that of the sufficient reason, by virtue of which we con-
sider that no fact can be real or existent, no statement true, unless there
is a sufficient reason why it is so and not otherwise, although for the
most part these reasons cannot be known to us.
33. There are also two sorts of truths, those of reasoning and those
of fact. Truths of reasoning are necessary and their opposite is impos-
sible, and those of fact are contingent and their opposite is possible.
When a truth is necessary its reason can be found by analysis, resolving
it into more simple ideas and truths until we reach those that are ele-
mental.
34. It is thus that mathematicians by analysis reduce speculative
theorems and practical canons to definitions, axioms and postulates.
35. Finally there are simple ideas, definitions of which cannot be
given ; there are also axioms and postulates, in a word, elementary prin-
ciples, which cannot be proved and indeed need no proof, and these are
identical propositions, the opposite of which contains a self-con-
tradiction.
36. But there must also be a sufficient reason for contingent truths,
or those of fact, — that is, for the series of things throughout the universe
of created objects — where the analysis into particular reasons might run
into a detail without limits, on account of the immense variety of objects
and the division of bodies ad infinitum. There is an infinity of figures
and of movements, present and past, which enter into the efficient cause
of my present writing, and there is an infinity of trifling motives and
dispositions, past and present, of my soul, which enter into the final
cause.
37. And as all such detail only depends on other contingents, ante-
rior or more detailed, each one of which needs a like analysis for its ex-
planation, we make no advance, and the sufficient or final reason must be
outside of the sequence or series of this detail of contingencies, however
infinite it may be.
THE BEGINNING OP MODERN PHILOSOPHY 85
38. And thus it is that the final cause of things must be found in
a necessary substance, in which the detail of changes exists only trans-
cendently, as in their source, and this is what we call God.
39. Now this substance being the sufficient reason of all this de-
tail, which also is linked together throughout, there is but one God, and
this God suffices.
40. We may judge also that this supreme essence, which is unique,
universal and necessary, having nothing outside of itself which is inde-
pendent of it, and being the simple series of possible being, must be in-
capable of limitations and must contain as much of reality as is possible.
41. Hence God is absolutely perfect, perfection being only the ex-
tension of positive reality taken in its strictest sense, setting aside the
limits or bounds to what is limited. And there where there are no lim-
its, that is, in God, perfection is absolutely infinite.
42. It follows also that creatures take their perfections from the
influence of God, but that their imperfections arise from their own na-
ture, which is incapable of existing without limits. For it is by this that
they are distinguished from God.
43. It is also true that in God is the ground not only of existence
but also of essences, so far as they are real, or of what is real in the pos-
sible. This is because the understanding of God is the source of eternal
truths, or of the ideas on which they depend, and because, without him,
nothing possible would be real and there would be not only nothing ex-
isting but also nothing possible.
44. Nevertheless, if there is any reality in essences or possibilities
or in eternal truths, this reality must be founded in something existing
and actual ; consequently in the existence of the necessary being in whom
essence involves existence or with whom to be possible is sufficient to be
actual.
45. Hence God (or the necessary being) alone has the character-
istic that he must exist if it is possible. And since nothing can hinder
the possibility of that which has no limitations, no negation, and, conse-
quently, no contradiction, this alone is enough to establish the existence
of God a priori. We have also proved it by the reality of eternal truths.
But we have just proved it also a posteriori, since contingent beings do
exist which can have their final cause or sufficient reason only in a neces-
sary being who has the reason of his existence in himself.
46. But it must not be thought, as is sometimes done, that eternal
truths, being dependent upon God, are arbitrary and depend upon his
86 THE BEGINNING OF MODERN PHILOSOPHY
will, as Descartes seems to have conceived, and afterwards M. Poiret.
This is true only of contingent truths, the principle of which is fitness
or the choice of the best, whereas necessary truths depend solely on his
understanding and are its internal nature.
47. Thus God alone is the elemental unity or the original simple
substance; of which all monads, created or derived, are the products,
and are born, so to speak, from moment to moment by continual emana-
tion of the Divinity, limited by the capacity of the creature, to which
limitation is essential.
48. In God is Power, which is the source of all things; then
Knowledge, which contains the detail of ideas ; and finally Will, which
effects changes or products according to the principles of what is best.
It is this which corresponds to what in created monads forms the sub-
ject or basis, the faculty of perception and desire. But in God these
attributes are absolutely infinite or perfect, and in the created monads
or in the entelechies (or perfectihabies, as Harmolaus Barbarus trans-
lated the word), they are only imitations proportioned to their per-
fection.
49. The creature is said to act in its environment in so far as it is
perfect, and to suffer from another in so far as it is imperfect. Thus
action is attributed to the monad in so far as it has clear perceptions,
and passiveness in so far as it has confused perceptions.
50. And one creature is more perfect than another in that there
is found in it what can account a priori for what takes place in another,
and it is in this way that one is said to act upon another.
51. But in simple substances the influence of one monad upon an-
other is purely ideal, since it can take effect only through the mediation
of God, inasmuch as in the ideas of God a monad may demand with rea-
son that God in regulating the others from the commencement of things,
have regard to it. For since a created monad can have no physical influ-
ence upon the interior of another, it is only in this way that one can be
dependent upon another.
52. And hence it is that the action and passiveness of creatures are
mutual. For God, in comparing two simple substances, finds in each
one reasons which compel him to adjust the other to it, and consequently
that which in certain respects is active, is from another point of view,
passive ; active in so far as what is known distinctly in it, serves to ac-
count for what takes place in another ; and passive in so far as the cause
of what takes place in it, is found in what is clearly known in another.
THE BEGINNING OF MODERN PHILOSOPHY 87
53. Now, as there is an infinity of possible universes in the mind
of God, and as only one of them can exist, there must be a sufficient
reason for the choice of God, by which He decides for one rather than
for another.
54. And this reason can only be found in the fitness, in the degree
of perfection, which these worlds contain, each possible world having
the right to claim existence according to the measure of perfection which
it would possess.
55. And this is the cause of the existence of the Best, which
wisdom makes known to God, which His goodness chooses and which
His power produces.
56. Now this connection, or this adaptation of all created things
to each and of each to all, brings it about that each simple substance in
its relations expresses all the others, and that consequently it is a living,
perpetual mirror of the universe.
57. And as the same city viewed from different sides appears en-
tirely different and in appearance is as if multiplied, so also it happens
that, because of the infinite multiplicity of simple substances, there are
as it were so many different universes, which are nevertheless only the
appearances of a single one, from the different points of view of each
monad.
58. And this is the way to obtain as great a variety as possible,
but with the greatest possible order ; that is, it is the way to obtain as
much perfection as possible.
59. Thus this hypothesis (which I dare to assert is proved) is
the only one which brings out the grandeur of God. M. Bayle recog-
nized this, when in his Dictionary (Art. Rorarius) he objected to it;
where indeed he was tempted to believe that I accorded to God more
than was possible. But he can state no reason why this universal har-
mony which brings it about that each substance expresses exactly all
others in the relations it sustains to them, is impossible.
60. Besides, we can see in what I have just said a priori reasons
why things could not be otherwise, because God, in regulating all, has
regard to each part, and especially to each monad, since, its nature being
representative, nothing can limit it to representing only a part of things ;
although it may be true that this representation is confused as regards
the detail of the whole universe, and distinct only in the case of a few
things, that is to say, in the case only of those which are nearest or larg-
est in relation to each of the monads — otherwise each monad would be
88 THE BEGINNING OP MODERN PHILOSOPHY
a divinity. It is not in the object but only in the modification of the
knowledge of the object, that monads are limited. They all tend con-
fusedly toward the infinite, toward the whole, but they are limited, and
are to be distinguished by their degree:, of clear perception.
61. And in this respect compound substances are like simple sub-
stances. For since the world is a plenum, making all matter interrelated,
and since in a plenum every movement has some effect on distant bodies
in proportion to their distance, so that each body is affected not only by
those that touch it and feels in some way all that happens to them, but
also by their means is affected by those which touch the first with which
it is in immediate contact, it follows that this communication extends
to every distance whatever. Therefore each body feels all that passes
in the universe, so that he who sees all, could read in each that which
passes everywhere else, and even that which has been or shall be, per-
ceiving in the present that which is distant in time as well as in space ;
sumpnoia panta, said Hippocrates. But a soul can read in itself only
what is expressly represented in it. It cannot develop its laws all at
once, for they reach into the infinite.
62. Thus, although each created monad represents all the universe,
it represents most distinctly the body which is particularly appropriated
to it and of which it forms the entelechy; and as this body represents
the entire universe by the interconnection of all matter in a plenum, the
soul also represents the whole universe by representing that body which
especially belongs to it.
63. The body belonging to a monad, which is the entelechy or
soul, constitutes, with the entelechy, what may be called a living being,
and with the soul, what may be called an animal. Now this body of a
living being or of an animal is always organic, for as every monad is
in a way a mirror of the universe, and as the universe is in perfect order,
there must also be an order in the representative, that is, in the percep-
tions of the soul, and hence in the body, in like manner as the universe
is represented in it.
64. Hence every organic body of a living being is a sort of divine
machine or natural automaton, which infinitely surpasses all artificial
automata, because a machine which is made by human art is not a ma-
chine in every one of its parts ; for example, the tooth of a brass wheel
has parts or fragments which to us are no longer artificial and have
nothing in themselves to show the use to which the wheel was destined
in the machine. But nature's machines, that is, living bodies, are ma-
THE BEGINNING OF MODERN PHILOSOPHY 89
chines even to their most infinitesimal parts. In this lies the difference
between nature and art, that is, between the divine art and ours.
65. And the author of nature has been able to contrive these di-
vine and infinitely marvellous works of art, because each particle of
matter is not only divisible ad infinitum, as the ancients perceived, but
also each part is actually infinitely subdivided into parts of which each
has its own motion ; otherwise it would be impossible for each portion
of matter to represent the universe.
66. Hence we see that there is a world of creatures, of living be-
ings, of animals, of entelechies, of souls, in the smallest particle of
matter.
67. Each particle of matter may be thought of as a garden full
of plants, or as a pond full of fishes. But each branch of the plant, each
member of the animal, each drop of its humors is also such a garden
or such a pond.
68. And although the earth or air between the plants of the gar-
den, or the water between the fish of the pond, is neither plant nor fish,
it yet contains more of them, but for the most part so tiny as to be
to us imperceptible.
69. Hence there is nothing uncultivated, sterile or dead in the uni-
verse, no chaos or confusion save in appearance, such as a pond would
present from a distance in which we might see the confused movement
and swarming, so to speak, of the fishes in the pond, without perceiving
the fish themselves.
70. Thus we see that every living body has a ruling entelechy that
is the soul of the animal, but the particles of this living body are full
of other living beings — plants, animals — each of which has also its
entelechy or governing soul.
71. But it must not be thought, as has been done by some people
who have misunderstood my idea, that every soul has a mass or portion
of matter allotted to it or united to it forever, and that hence it possesses
other inferior living beings doomed to its service forever. For all bodies
are, like rivers, in a perpetual flux, and parts are always joining and
leaving them.
72. Hence the soul changes its body only gradually and by de-
grees, so that it is never deprived of all its organs at once. There is
often a metamorphosis in animals, but never a metempsychosis or
transmigration of souls. There are also no absolutely separate souls,
nor genii without bodies. Only God is wholly without body.
V 6-6
90 THE BEGINNING OF MODERN PHILOSOPHY
73. For which reason also, it follows that there is, strictly speak-
ing, neither absolute generation nor absolute death, where the soul is
separated from the body. What we call generation is development or
increase, as also what we call death is involution and diminution.
74. Philosophers have been greatly puzzled over the origin of
forms, entelechies, or souls; but now, when we know by close investi-
gation of plants, insects and animals, that organic bodies in nature are
never generated hit and miss or from putrefaction, but always from
seeds, in which there was undoubtedly some pre-formation, it has been
thought that not only the organic body was already there before con-
ception, but also a soul in this body, and, in a word, the animal itself;
and that by means of conception this animal has merely been destined
to a greater transformation, in order to become an animal of another
kind. Something like this is seen outside of generation, as when worms
become flies, and caterpillars, butterflies.
75. Of such animals, those that are raised by conception to the
grade of larger animals, may be called spermatics; but those which re-
main in their class, that is, the most part, are born, multiply, and die
like the larger animals, and there is only a small number of chosen ones,
which pass to a larger theater.
76. But this tells only half the truth; I have therefore thought
that if the animal never naturally has a beginning, it cannot end nat-
urally ; and that not only will there be no generation, but also no abso-
lute destruction or death strictly speaking. And these reasonings, made
a posteriori and drawn from experience, harmonizes perfectly with prin-
ciples deduced a priori, as above.
77. Thus it may be said that not only is the soul (the mirror of
an indestructible universe) indestructible, but also the animal itself, al-
though its machine often perishes in part and takes on or puts off organic
spoils.
78. These principles have given me the means of explaining nat-
urally the union or rather the conformity of the soul and the organic
body. The soul follows its own peculiar laws and the body also fol-
lows its own laws, and they meet by virtue of the pre-established har-
mony between all substances, since they all represent one and the same
universe.
79. Souls act according to the laws of final causes, by desires, ends
and means. Bodies act in accordance with the laws of efficient causes
or of motion. And the two realms, that of efficient causes and that of
final causes, are in harmony with each other.
THE BEGINNING OF MODERN PHILOSOPHY 91
80. Descartes saw that souls cannot add any motion to bodies,
because there is always the same quantity of force in matter ; neverthe-
less he believed that the soul could change the direction of the motion.
But it was because, in his day, the law of nature which declares the con-
servation of the total direction in matter, was not known. If he had
known this, he would have lighted upon my system of the pre-estab-
lished harmony.
81. Under this system bodies can act as if (what is impossible)
there were no souls, and souls act as if there were no bodies, and both
act as if each influenced the other.
82. Although I find that the same thing I have stated — namely,
that animals and souls begin only with the world and end only with the
world — holds good in the end with regard to all animals and living
things, yet there is this peculiarity in rational animals, that their sper-
matic animalcules, as such, have only ordinary or sensitive souls, but as
soon as those which are, so to speak, elected, attain by actual conception
to human nature, their sensitive souls are elevated to the rank of rea-
son and to the prerogative of spirits.
83. Among other differences that exist between ordinary souls
and spirits, a part of which I have already mentioned, there is also this,
that souls in general are the living mirrors or images of the universe of
creatures, but spirits are in addition images of the Divinity itself, or of
the author of nature, able to know the system of the universe and to
imitate something of it constructively, since every spirit is like a little
divinity in its own department.
84. For this reason the spirits can enter into a sort of society with
God, and He is, in relation to them, not only what an inventor is to his
machines (as God is in relation to the other creatures), but also what
a prince is to his subjects or even a father to his children.
85. Whence it is easy to conclude that the community of all spir-
its must compose the City of God, that is, the most perfect state which
is possible, under the most perfect of monarchs.
86. This City of God, this truly universal dominion, is a moral
world vrithin the natural world, and the highest and most divine of the
works of God ; it is in this that the glory of God truly consists, for He
would have none if His greatness and goodness were not known and
admired by spirits. It is, too, only in relation to the divine city that He
possesses, properly, goodness ; while His wisdom and power are every-
where manifest.
92 THE BEGINNING OF MODERN PHILOSOPHY
87. As we have thus established perfect harmony between two
natural kingdoms, the one of efficient, the other of final causes, we
should also notice here another harmony between the physical kingdom
of nature and the moral kingdom of grace ; that is, between God consid-
ered as an architect of the mechanism of the universe, and God, consid-
ered as monarch of the divine city of souls.
88. This harmony makes all things evolve toward grace by nat-
ural methods. This globe, for example, must be destroyed and repaired
by natural means, at such times as the government of spirits may de-
mand it, for the punishment of some and the reward of others.
89. It may be said, besides, that God the architect satisfies in every
respect God the legislator, and that therefore sins, by the laws of nature
and even the mechanical structure of things, must carry their punish-
ment with them; and that good actions will obtain their rewards by
mechanical ways through their relation to bodies, although this may
not and ought not always take place at once.
90. Finally, under this perfect government, there will be no good
action without its reward, no bad action without its atonement, and
everything must result for the well-being of the good, that is, of those
who are not out of harmony with this great State, who, after having
done their duty, trust in providence, and who love and imitate as they
ought the author of all good, pleasing themselves with the contemplation
of His perfections, — according to the nature of truly pure love, which
is happy in the happiness of the loved one. This is why the wise and
virtuous work at all things which seem in harmony with the divine will,
presumptive or antecedent, and yet content themselves with what God
actually sends by His secret, consequent and decisive will, recognizing
that if we could sufficiently comprehend the order of th'e universe we
would find that it surpassed all the wishes of the wisest, and that it is
impossible to make it better than it is, not only for all in general, but
even for ourselves in particular, if we are attached, as we should be,
to the Author of all, not only as the architect and efficient cause of our
being, but also as our master and final cause, who should be the only
aim of our efforts, and who can alone secure our happiness.
THE BEGINNING OF MODERN PHILOSOPHY 83
HOBBES
THOMAS HOBBES was born at Westport (now part of Malmesbury)
April 5, 1588. His father, vicar of the place, got into trouble by quar-
relling with a rival, and left his children to the care of his brother, a
glover of Malmesbury. He early studied Greek and Latin and at fif-
teen entered Oxford, where he was graduated in 1608, although he
seems to have taken little interest in the scholastic learning of the time.
For some years afterwards he was tutor, then secretary and friend
to young Cavendish. Cavendish died in 1628, but in 1631 Hobbes be-
came the tutor of the son.
In 1637 he became interested in the idea that everything, mind
included, can be explained by being referred to motion in nature. Then
came the Puritan revolution, and Hobbes took the side of the Stuart
kings, — in fact, in 1647 he was made instructor in mathematics of the
exiled Prince of Wales. His Leviathan was published in 1651. In it
he tried to apply mechanical principles to society as he had previously
tried to assign them to nature. Society he thought to be an organism, its
basis a contract by which the people had alienated their rights to the
king in return for protection. He considered the best government to
be a monarchy, but raised the question of the right of the subject to
change allegiance when the power of the king to protect is gone.
This brought him enemies on both sides, and he took the least dangerous
course and returned to England. His doctrines of a mechanical nature
and society offended the clergy, but after the Restoration he was re-
ceived with some honor by the king, and the only punishment he re-
ceived was the condemnation of his works by parliament as atheistic
(1666). He died in 1679.
The question of what was the supreme power in the state was
handed down along with the idea of the Social Contract to Locke and
Rousseau.
The Leviathan besides containing the idea that society is an organ-
ism, and the theory of the Social Contract, given in the following vol-
ume, psychologically traces all sensation to motion in the body and its
94 THE BEGINNING OP MODERN PHILOSOPHY
environment. The carrying out of this theory of sense to its logical
limit would make mental facts as entirely subject to natural laws as
physical. Hence Hobbes' influence, which still persists, is on the side
of materialism. Something of his idea that motion is the cause of all
sensation follows.
OF MAN
CHAPTER I.
OF SENSE
CONCERNING the thoughts of man, I will consider them first singly,
and afterwards in train, or dependence upon one another. Singly, they
are every one a representation or appearance, of some quality, or other
accident of a body without us, which is commonly called an object.
Which object worketh on the eyes, ears, and other parts of a man's
body ; and by diversity of working, produceth diversity of appearances.
The original of them all, is that which we call SENSE, for there is
no conception in a man's mind, which hath not at first, totally, or by
parts, been begotten upon the organs of sense. The rest are derived
from that original.
To know the natural cause of sense, is not very necessary to the
"business now in hand; and I have elsewhere written of the same at
large. Nevertheless, to fill each part of my present method, I will
briefly deliver the same in this place.
The cause of sense, is the external body, or object which presseth
the organ proper to each sense, either immediately, as in the taste and
touch; or mediately, as in seeing, hearing, and smelling; which pres-
sure, by the mediation of the nerves, and other strings and membranes
of the body, continued inwards to the brain and heart, causeth there a
resistance, or counter-pressure, or endeavour of the heart to deliver
itself, which endeavour, because outward, seemeth to be some matter
without. And this seeming, or fancy, is that which men call sense; and
consisteth, as to the eye, in a light, or colour figured; to the ear, in a
sound; to the nostril, in an odour; to the tongue and palate, in a savour;
and to the rest of the body, in heat, cold, hardness, softness, and such
other qualities as we discern by feeling. All which qualities, called sen-
sible, are, in the object that causeth them, but so many several motions
THE BEGINNING OF MODERN PHILOSOPHY 95
of the matter, by which it presseth our organs diversely. Neither in us
that are pressed, are they any thing else but divers motions ; for motion
produceth nothing but motion. But their appearance to us is fancy, the
same waking, that dreaming. And as pressing, rubbing, or striking the
eye, makes us fancy a light ; and pressing the ear, produceth a din ; so do
the bodies also we see, or hear, produce the same by their strong, though
unobserved action. For if those colours and sounds were in the bodies,
or objects that cause them, they could not be severed from them, as by
glasses, and in echoes by reflection, we see they are ; where we know the
thing we see is in one place, the appearance in another. And though at
some certain distance, the real and very object seem invested with the
fancy it begets in us; yet still the object is one thing, the image or
fancy is another. So that sense, in all cases, is nothing else but orig-
inal fancy, caused, as I have said, by the pressure, that is, by the motion,
of external things upon our eyes, ears, and other organs thereunto or-
dained.
But the philosophy-schools, through all the universities of Chris-
tendom, grounded upon certain texts of Aristotle, teach another doc-
trine, and say, for the cause of vision, that the thing seen sendeth forth
on every side a visible species, in English, a visible show, apparition, or
aspect, or a being seen; the receiving whereof into the eye, is seeing.
And for the cause of hearing, that the thing heard sendeth forth an
audible species, that is, an audible aspect, or audible being seen; which
audible species, that is an audible aspect, or audible being seen; which
entering at the ear, maketh hearing. Nay, for the cause of understand-
ing also, they say the thing understood, sendeth forth an intelligible
species, that is, an intelligible being seen; which, coming into the under-
standing, makes us understand. I say not this, as disproving the use of
universities; but because I am to speak hereafter of their office in a
commonwealth, I must let you see on all occasions by the way, what
things would be amended in them ; amongst which the frequency of in-
significant speech is one.
CHAPTER II.
OF IMAGINATION
THAT when a thing lies still, unless somewhat else stir it, it will
lie still for ever, is a truth that no man doubts of. But that when a
thing is in motion, it will eternally be in motion, unless somewhat else
stay it, though the reason be the same, namely, that nothing can change
96 THE BEGINNING OF MODERN PHILOSOPHY
itself, is not so easily assented to. For men measure, not only other
men, but all other things, by themselves ; and because they find them-
selves subject after motion to pain, and lassitude, think every thing
else grows weary of motion, and seeks repose of its own accord ; little
considering, whether it be not some other motion, wherein that desire
of rest they find in themselves, consisteth. From hence it is, that the
schools say, heavy bodies fall downwards, out of an appetite to rest, and
to conserve their nature in that place which is most proper for them;
ascribing appetite, and knowledge of what is good for their conserva-
tion, which is more than man has, to things inanimate, absurdly.
When a body is once in motion, it moveth, unless something else
hinder it, eternally; and whatsoever hindreth it, cannot in an instant,
but in time, and by degrees, quite extinguish it; and as we see in the
water, though the wind cease, the waves give not over rolling for a long
time after : so also it happeneth in that motion, which Is made in the
internal parts of a man, then, when he sees, dreams, &c. For after the
object is removed, or the eye shut, we still retain an image of the thing
seen, though more obscure than when we see it. And this is it, the
Latins call imagination, from the image made in seeing ; and apply the
same, though improperly, to all the other senses. But the Greeks call it
fancy; which signifies appearance, and is as proper to one sense, as to
another. IMAGINATION therefore is nothing but decaying sense; and is
found in men, and many other living creatures, as well sleeping, as
waking.
The decay of sense in men waking, is not the decay of the motion
made in sense ; but an obscuring of it, in such manner as the light of the
sun obscureth the light of the stars; which stars do no less exercise
their virtue, by which they are visible, in the day than in the night.
But because amongst many strokes, which our eyes, ears, and other
organs receive from external bodies, the predominant only is sensible;
therefore, the light of the sun being predominant, we are not affected
with the action of the stars. And any object being removed from our
eyes, though the impression it made in us remain, yet other objects
more present succeeding, and working on us, the imagination of the
past is obscured, and made weak, as the voice of a man is in the noise
of the day. From whence it followeth, that the longer the time is, after
the sight or sense of any object, the weaker is the imagination. For
the continual change of man's body destroys in time the parts which in
sense were moved : so that distance of time, and of place, hath one and
THE BEGINNING OF MODERN PHILOSOPHY 97
the same effect in us. For as at a great distance of place, that which
we look at appears dim, and without distinction of the smaller parts;
and as voices grow weak, and inarticulate ; so also, after great distance
of time, our imagination of the past is weak ; and we lose, for example,
of cities we have seen, many particular streets, and of actions, many par-
ticular circumstances. This decaying sense, when we would express the
thing itself, I mean fancy itself, we call imagination, as I said before :
but when we would express the decay, and signify that the sense is fad-
ing, old, and past, it is called memory. So that imagination and memory
are but one thing, which for divers considerations hath divers names.
Much memory, or memory of many things, is called experience.
Again, imagination being only of those things which have been for-
merly perceived by sense, either all at once, or by parts at several times ;
the former, which is the imagining the whole object as it was presented
to the sense, is simple imagination, as when one imagineth a man, or
horse, which he hath seen before. The other is compounded; as when,
from the sight of a man at one time, and of a horse at another, we con-
ceive in our mind a Centaur. So when a man compoundeth the image of
his own person with the image of the actions of another man, as when
a man imagines himself a Hercules or an Alexander, which happeneth
often to them that are much taken with reading of romances, it is a com-
pound imagination, and properly but a fiction of the mind. There be
also other imaginations that rise in men, though waking, from the great
impression made in sense : as from gazing upon the sun, the impression
leaves an image of the sun before our eyes a long time after ; and from
being long and vehemently attent upon geometrical figures, a man shall
in the dark, though awake, have the images of lines and angles before
his eyes ; which kind of fancy hath no particular name, as being a thing
that doth not commonly fall into men's discourse.
The imaginations of them that sleep are those we call dreams.
And these also, as all other imaginations, have been before, either to-
tally or by parcels, in the sense. And because in sense, the brain and
nerves, which are the necessary organs of sense, are so benumbed in
sleep, as not easily to be moved by the action of external objects, there
can happen in sleep no imagination, and therefore no dream, but what
proceeds from the agitation of the inward parts of man's body ; which
inward parts, for the connexion they have with the brain, and other
organs, when they be distempered, do keep the same in motion ; whereby
the imaginations there formerly made, appear as if a man were waking ;
98 THE BEGINNING OF MODERN PHILOSOPHY
saving that the organs of sense being now benumbed, so as there is no
new object, which can master and obscure them with a more vigorous
impression, a dream must needs be more clear, in this silence of sense,
than our waking thoughts. And hence it cometh to pass, that it is a hard
matter, and by many thought impossible, to distinguish exactly between
sense and dreaming. For my part, when I consider that in dreams I
do not often nor constantly think of the same persons, places, objects,
and actions, that I do waking; nor remember so long a train of coher-
ent thoughts, dreaming, as at other times ; and because waking I often
observe the absurdity of dreams, but never dream of the absurdities
of my waking thoughts ; I am well satisfied, that being awake, I know I
dream not, though when I dream I think myself awake.
CHAPTER VI.
OF THE INTERIOR BEGINNINGS OF VOLUNTARY MOTIONS; COMMONLY
CALLED THE PASSIONS ' AND THE SPEECHES BY WHICH
THEY ARE EXPRESSED
THERE be in animals, two sorts of motions peculiar to them : one
called vital; begun in generation, and continued without interruption
through their whole life ; such as are the course of the blood, the pulse,
the breathing, the concoction, nutrition, excretion, &c., to which motions
there needs no help of imagination : the other is animal motion, other-
wise called voluntary motion; as to go, to speak, to move any of our
limbs, in such manner as is first fancied in our minds. (That sense is
motion in the organs and interior parts of man's body, caused by the
action of the things we see, hear, &c. ; and that fancy is but the relics of
the same motion, remaining after sense, has been already said in the
first and second chapters.) And because going, speaking, and the like
voluntary motions, depend always upon a precedent thought of whither,
which -way, and what; it is evident, that the imagination is the first in-
ternal beginning of all voluntary motion. And although unstudied men
do not conceive any motion at all to be there, where the thing moved is
invisible ; or the space it is moved in is, for the shortness of it, insensible ;
yet that doth not hinder, but that such motions are. For let a space be
never so little, that which is moved over a greater space, whereof that
little one is part, must first be moved over that. These small beginnings
of motion, within the body of man, before they appear in walking, speak-
ing, striking, and other visible actions, are commonly called ENDEAVOUR.
This endeavour, when it is toward something which causes it, is
THE BEGINNING OP MODERN PHILOSOPHY 99
called APPETITE, or DESIRE ; the latter, being the general name ; and the
other oftentimes restrained to signify the desire of food, namely hunger
and thirst. And when the endeavour is fromward something, it is gen-
erally called AVERSION. These words, appetite and aversion, we have
from the Latins ; and they both of them signify the motions one of ap-
proaching, the other of retiring. So also do the Greek words for the
same, which are horma and aphorma. For nature itself does often
press upon men those truths, which afterwards, when they look for
somewhat beyond nature, they stumble at. For the Schools find in mere
appetite to go, or move, no actual motion at all : but because some mo-
tion they must acknowledge, they call it metaphorical motion ; which is
but an absurd speech: for though words may be called metaphorical;
bodies and motions can not.
That which men desire, they are also said to LOVE : and to HATE
those things for which they have aversion. So that desire and love are
the same thing; save that by desire, we always signify the absence of
the object; by love, most commonly the presence of the same. So also
by aversion, we signify the absence; and by hate, the presence of the
object.
Of appetites and aversions, some are born with men ; as appetite of
food, appetite of excretion, and exoneration, which may also and more
properly be called aversions, from somewhat they feel in their bodies ;
and some other appetites, not many. The rest, which are appetites of
particular things, proceed from experience, and trial of their effects
upon themselves or other men. For of things we know not at all, or
believe not to be, we can have no further desire, than to taste and try.
But aversion we have for things, not only which we know have hurt us,
but also that we do not know whether they will hurt us, or not.
Those things which we neither desire, nor hate, we are said to
contemn; CONTEMPT being nothing else but an immobility, or contu-
macy of the heart, in resisting the action of certain things ; and proceed-
ing from that the heart is already moved otherwise, by other more
potent objects ; or from want of experience of them.
And because the constitution of a man's body is in continual muta-
tion, it is impossible that all the same things should always cause in him
the same appetites, and aversions ; much less can all men consent, in the
desire of almost any one and the same object.
But whatsoever is the object of any man's appetite or desire, that is
it which he for his part calleth good: and the object of his hate and aver-
100 THB BEGINNING OF MODERN PHILOSOPHY
sion, evil; and of his contempt, vile and inconsiderable. For these words
of good, evil, and contemptible, are ever used with relation to the person
that useth them : there being nothing simply and absolutely so ; nor any
common rule of good and evil, to be taken from the nature of the ob-
jects themselves ; but from the person of the man, where there is no com-
monwealth ; or, in a commonwealth, from the person that represented! it ;
or from an arbitrator or judge, whom men disagreeing shall by consent
set up, and make his sentence the rule thereof.
The Latin tongue has two words, whose significations approach to
those of good and evil; but are not precisely the same; and those are
pulchrum and turpe. Whereof the former signifies that which by some
apparent signs promiseth good; and the latter, that which promiseth
evil. But in our tongue we have not so general names to express them
by. But for pulchrum we say in some things, fair; in others, beautiful,
or handsome, or gallant, or honourable, or comely, or amiable; and for
turpe, foul, deformed, ugly, base, nauseous, and the like, as the subject
shall require; all which words, in their proper places, signify nothing
else but the mien, or countenance, that promiseth good and evil. So
that of good there be three kinds ; good in the promise, that is pulchrum;
good in effect, as the end desired, which is called jucundum, delightful;
and good as the means, which is called utile, profitable; and as many of
evil : for evil in promise, is that they call turpe; evil in effect, and end, is
molestum, unpleasant, troublesome; and evil in the means, inutile, un-
profitable, hurtful.
As, in sense, that which is really within us, is, as I have said before,
only motion, caused by the action of external objects, but in apparence;
to the sight, light and colour ; to the ear, sound ; to the nostril, odour,
&c. : so, when the action of the same object is continued from the eyes,
ears, and other organs to the heart, the real effect there is nothing but
motion, or endeavour; which consisteth in appetite, or aversion, to or
from the object moving. But the apparence, or sense of that motion,
is that we either call delight, or trouble of mind.
This motion, which is called appetite, and for the apparence of it
delight, and pleasure, seemeth to be a corroboration of vital motion, and
a help thereunto ; and therefore such things as caused delight, were not
improperly called jucunda, a juvando, from helping or fortifying ; and
the contrary, molest a, offensive, from hindering, and troubling the mo-
tion vital.
Pleasure therefore, or delight, is the apparence, or sense of good;
THE BEGINNING OP MODERN PHILOSOPHY 101
and molestation, or displeasure, the apparence, or sense of evil. And
consequently all appetite, desire, and love, is accompanied with some
delight more or less ; and all hatred and aversion, with more or less dis-
pleasure and offence.
Of pleasures or delights, some arise from the sense of an object
present ; and those may be called pleasure of sense; the word sensual,
as it is used by those only that condemn them, having no place till there
be laws. Of this kind are all onerations and exonerations of the body ;
as also all that is pleasant, in the sight, hearing, smell, taste, or touch.
Others arise from the expectation, that proceeds from foresight of the
end, or consequence of things ; whether those things in the sense please
or displease. And these are pleasures of the mind of him that draweth
those consequences, and are generally called JOY. In the like manner,
displeasures are some in the sense, and called PAIN; others in the ex-
pectation of consequences, and are called GRIEF.
These simple passions called appetite, desire, love, aversion, hate,
joy, and grief, have their names for divers considerations diversified.
As first, when they one succeed another, they are diversely called from
the opinion men have of the likelihood of attaining what they desire.
Secondly, from the object loved or hated. Thirdly, from the considera-
tion of many of them together. Fourthly, from the alteration or succes-
sion itself.
LOCKE
JOHN LOCKE was born at Wrington, Somersetshire, England, in
1632. His first education was at Westminster School, London. From
1651 to 1664 he was at Oxford. Three years later he became a member
of the family of Lord Ashley, afterwards Earl of Shaftesbury, and was
led into politics. He received several offices and became something of
a leader of political thought. His Civil Government was too liberal to
suit King James, and Locke was forced to live on the continent for five
years. In 1690 he published his Essay on the Human Understanding.
The book marks the beginning of descriptive psychology, for, while its
avowed purpose is "to inquire into the original, certainty, and extent
102 THE BEGINNING OF MODERN PHILOSOPHY
of human knowledge," yet it is actually a descriptive analysis of knowl-
edge more than an examination of the ground of all knowledge. Be-
sides this analysis, however, there are two features of Locke's system
that have had great influence. The first is that he declares all knowledge
to come from experience, i. e., from sensation and subsequent reflec-
tion. The second is that he points out that our sensations are not the
things themselves, nor necessarily copies of the things, but that they
represent powers or qualities, and that we presuppose the things as a
support for a number of such qualities, the sensations from which are
continually recurring together in our mind. Hence Locke is the spirit
of sensualistic materialism on the one side, and on the other from his
doctrine that substance is merely something presupposed as the ground
of sensations grew Berkeley's idealism.
He died October 28, 1704.
IDEAS
OF IDEAS IN GENERAL AND THEIR ORIGINAL
1. Idea is the Object of Thinking. — Every man being conscious
to himself that he thinks, and that which his mind is applied about
whilst thinking, being the ideas that are there, it is past doubt that men
have in their minds several ideas, such as are those expressed by the
words whiteness, hardness, sweetness, thinking, motion, man, elephant,
army, drunkenness, and others. It is in the first place then to be in-
quired how he comes by them. I know it is a received doctrine that
men have native ideas and original characters stamped upon their minds
in their very first being. This opinon I have at large examined already ;
and I suppose what I have said in the foregoing book will be much more
easily admitted when I have shown whence the understanding may get
all the ideas it has, and by what ways and degrees they may come into
the mind ; for which I shall appeal to every one's own observation and
experience.
2. All Ideas Come from Sensation or Reflection. — Let us then sup-
pose the mind to be, as we say, white paper, void of all characters, with-
out any ideas ; how comes it to be furnished ? Whence comes it by that
vast store which the busy and boundless fancy of man has painted on it
with an almost endless variety? Whence has it all the materials of
reason and knowledge ? To this I answer in one word, from experience ;
THE BEGINNING OF MODERN PHILOSOPHY 103
in that all our knowledge is founded, and from that it ultimately derives
itself. Our observation employed either about external sensible objects,
or about the internal operations of our minds, perceived and reflected
on by ourselves, is that which supplies our understandings with all the
materials of thinking. These two are the fountains of knowledge from
whence all the ideas we have or can naturally have do spring.
3. The Objects of Sensation one Source of Ideas. — Firs^, our
senses, conversant about particular sensible objects, do convey into the
mind several distinct perceptions of things, according to those various
ways wherein those objects do affect them; and thus we come by those
ideas we have of yellow, white, heat, cold, soft, hard, bitter, sweet, and
all those which we call sensible qualities ; which when I say the senses
convey into the mind, I mean, they from external objects convey into the
mind what produces there those perceptions. This great source of most
of the ideas we have, depending wholly upon our senses, and derived
by them to the understanding, I call SENSATION.
4. The Operations of Our Minds, the other Source of them. —
Secondly, the other fountain, from which experience furnisheth the un-
derstanding with ideas, is the perception of the operations of our own
mind within us, as it is employed about the ideas it has got ; which oper-
ations, when the soul comes to reflect on and consider, do furnish the
understanding with another set of ideas, which could not be had from
things without ; and such are perception, thinking, doubting, believing,
reasoning, knowing, willing, and all the different actings of our own
minds; which we being conscious of, and observing in ourselves, do
from these receive into our understandings as distinct ideas, as we do
from bodies affecting our senses. This source of ideas every man has
wholly in himself ; and though it be not sense, as having nothing to do
with external objects, yet it is very like it, and might properly enough
be called internal sense. But as I call the other Sensation, so I call this
REFLECTION, the ideas it affords being such only as the mind gets by
reflecting on its own operations within itself. By reflection then, in the
following part of this discourse, I would be understood to mean that
notice which the mind takes of its own operations, and the manner of
them ; by reason whereof there come to be ideas of these operations in
the understanding. These two, I say, viz., external material things, as
the objects of sensation ; and the operations of our own minds within,
as the objects of reflection; are to me the only originals from whence
all our ideas take their beginnings. The term operations here I use in
104 THE BEGINNING OF MODERN PHILOSOPHY
a large sense, as comprehending not barely the actions of the mind
about its ideas, but some sort of passions arising sometimes from them,
such as is the satisfaction or uneasiness arising from any thought.
5. All our Ideas are of the one or the other of these. — The under-
standing seems to me not to have the least glimmering of any ideas
which it doth not receive from one of these two. External objects fur-
nish the mind with the ideas of sensible qualities, which are all those
different perceptions they produce in us; and the mind furnishes the
understanding with ideas of its own operations.
These, when we have taken a full survey of them, and their several
modes, combinations, and relations, we shall find to contain all our whole
stock of ideas; and that we have nothing in our minds, which did not
come in one of these two ways. Let any one examine his own thoughts,
and thoroughly search into his understanding ; and then let him tell me,
whether all the original ideas he has there, are any other than of the
objects of his senses, or of the operations of his mind, considered as
objects of his reflection : and how great a mass of knowledge soever he
imagines to be lodged there, he will, upon taking a strict view, see that
he has not any idea in his mind, but what one of these two have im-
printed, though, perhaps, with infinite variety compounded and enlarged
by the understanding, as we shall see hereafter.
6. Observable in Children. — He that attentively considers the state
of a child, at his first coming into the world, will have little reason to
think him stored with plenty of ideas, that are to be the matter of his
future knowledge : it is by degrees he comes to be furnished with them.
And though the ideas of obvious and familiar qualities imprint them-
selves before the memory begins to keep a register of time or order, yet
it is often so late before some unusual qualities come in the way, that
there are few men that cannot recollect the beginning of their acquain-
tance with them ; and if it were worth while, no doubt a child might be
so ordered as to have but a very few, even of the ordinary ideas, till he
were grown up to a man. But all that are born into the world being
surrounded with bodies that perpetually and diversely affect them, va-
riety of ideas, whether care be taken of it or not, are imprinted on the
minds of children. Light and colours are busy at hand everywhere,
when the eye is but open ; sounds of some tangible qualities fail not to
solicit their proper senses, and force an entrance to the mind ; but yet,
I think, it will be granted easily, that if a child were kept in a place
where he never saw any other but black and white till he were a man,
THE BEGINNING OF MODERN PHILOSOPHY 105
he would have no more ideas of scarlet or green, than he that from his
childhood never tasted an oyster or a pine-apple has of those particular
relishes.
7. Men are differently furnished with these, according to the dif-
ferent Objects they converse with. — Men then come to be furnished
with fewer or more simple ideas from without, according' as the objects
they converse with afford greater or less variety ; and from the opera-
tions of their minds within, according as they more or less reflect on
them. For though he that contemplates the operations of his mind, can-
not but have plain and clear ideas of them ; yet, unless he turns his
thoughts that way, and considers them attentively, he will no more
have clear and distinct ideas of all the operations of his mind, and all
that may be observed therein, than he will have all the particular ideas
of any landscape, or of the parts and motions of a clock, who will not
turn his eyes to it, and with attention heed all the parts of it. The pic-
ture or clock may be so placed, that they may come in his way every
day ; but yet he will have but a confused idea of all the parts they are
made up of, till he applies himself with attention to consider them each
in particular.
8. Ideas of Reflection later, because they need Attention. — And
hence we see the reason why it is pretty late before most children get
ideas of the operations of their own minds ; and some have not any very
clear or perfect ideas of the greatest part of them all their lives; be-
cause, though they pass there continually, yet, like floating visions, they
make not deep impressions enough to leave in their mind clear, distinct,
lasting ideas, till the understanding turns inward upon itself, reflects on
its own operations, and makes them the objects of its own contempla-
tion. Children when they come first into it, are surrounded with a world
of new things, which, by a constant solicitation of their senses, draw the
mind constantly to them, forward to take notice of new, and apt to be
delighted with the variety of changing objects. Thus the first years
are usually employed and diverted in looking abroad. Men's business
in them is to acquaint themselves with what is to be found without ; and
so growing up in a constant attention to outward sensation, seldom make
any considerable reflection on what passes within them till they come
to be of riper years, and some scarce ever at all.
9. The Soul begins to have Ideas when it begins to perceive. — To
ask at what time a man has first any ideas, is to ask when he begins to
perceive ; having ideas, and perception, being the same thing. I know
V 6-7
106 THE BEGINNING OP MODERN PHILOSOPHY
it is an opinion, that the soul always thinks, and that it has the actual
perception of ideas in itself constantly, as long as it exists, and that ac-
tual thinking is as inseparable from the soul as actual extension is from
the body ; which, if true, to inquire after the beginning of a man's ideas,
is the same as to inquire after the beginning of his soul; for by this
account, soul and its ideas, as body and its extension, will begin to exist
both at the same time.
IDEAS AND THINGS
7. Ideas in the Mind, Qualities in Bodies. — To discover the nature
of our ideas the better, and to discourse of them intelligently, it will be
convenient to distinguish them as they are ideas or perceptions in our
minds, and as they are modifications of matter in the bodies that cause
such perceptions in us, that so we may not think (as perhaps usually is
done) that they are exactly the images and resemblances of something
inherent in the subject ; most of those of sensation being in the mind no
more the likeness of something existing without us, than the names that
stand for them are the likeness of our ideas, which yet upon hearing
they are apt to excite in us.
8. Whatsoever the mind perceives in itself, or is the immediate
object of perception, thought, or understanding, that I call idea; and the
power to produce any idea in our mind, I call quality of the subject
wherein that power is. Thus a snowball having the power to produce
in us the ideas of white, cold, and round, the power to produce these
ideas in us, as they are in the snowball, I call qualities ; and as they are
sensations or perceptions in our understandings, I call them ideas;
which ideas, if I speak of sometimes as in the things themselves, I would
be understood to mean those qualities in the objects which produce them
in us.
9. Primary Qualities. — Qualities thus considered in bodies are,
first, such as are utterly inseparable from the body, in what state soever
it be ; such as in all the alterations and changes it suffers, all the force
can be used upon it, it constantly keeps ; and such as sense constantly
finds in every particle of matter which has bulk enough to be perceived
and the mind finds inseparable from every particle of matter, though
less than to make itself singly be perceived by our senses, e. g., take a
grain of wheat, divide it into two parts, each part has still solidity, ex-
tension, figure, and mobility; divide it again, and it retains still the
THE BEGINNING OF MODERN PHILOSOPHY 107
same qualities ; and so divide it on till the parts become insensible, they
must retain still each of them all those qualities. For division (which
is all that a mill, or pestle, or any other body, does upon another, in re-
ducing it to insensible parts) can never take away either solidity, exten-
sion, figure, or mobility from any body, but only makes two or more
distinct separate masses of matter, of that which was but one before;
all which distinct masses, reckoned as so many distinct bodies, after di-
vision, makes a certain number. These I call original or primary quali-
ties of body, which I think we may observe to produce simple ideas in
us, viz., solidity, extension, figure, motion or rest, and number.
10. Secondary Qualities. — Secondly, such qualities which in truth
are nothing in the objects themselves, but powers to produce various sen-
sations in us by their primary qualities, i. e., by the bulk, figure, texture,
and motion of their insensible parts, as colours, sounds, tastes, etc., these
I call secondary qualities. To these might be added a third sort, which
are allowed to be barely powers, though they are as much real qualities
in the subject, as those which I, to comply with the common way of
speaking, call qualities, but for distinction, secondary qualities. For the
power in fire to produce a new colour or consistency in wax or clay,
by its primary qualities, is as much a quality in fire as the power it has
to produce in me a new idea or sensation of warmth or burning, which
I felt not before, by the same primary qualities, viz., the bulk, texture,
and motion of its insensible parts.
11. How primary Qualities produce their Ideas. — The next thing
to be considered is, how bodies produce ideas in us ; and that is mani-
festly by impulse, the only way which we can conceive bodies to op-
erate in.
12. If then external objects be not united to our minds when they
produce ideas therein, and yet we perceive these original qualities in
such of them as singly fall under our senses, it is evident that some
motion must be thence continued by our nerves or animal spirits, by
some parts of our bodies to the brain, or the seat of sensation, there
to produce in our minds the particular ideas we have of them. And
since the extension, figure, number, and motion of bodies of an observ-
able bigness, may be perceived at a distance by the sight, it is evident
some singly imperceptible bodies must come from them to the eyes,
and thereby convey to the brain some motion, which produces these ideas
which we have of them in us.
13. How secondary. — After the same manner that the ideas of
108 THE BEGINNING OP MODERN PHILOSOPHY
these original qualities are produced in us, we may conceive that the
ideas of secondary qualities are also produced, viz., by the operations
of insensible particles on our senses. For it being manifest that there
are bodies and good store of bodies, each whereof are so small, that we
cannot by any of our senses discover either their bulk, figure, or motion,
as is evident in the particles of the air and water, and others extremely
smaller than those, perhaps as much smaller than the particles of air
and water, as the particles of air and water are smaller than peas or
hail-stones; let us suppose at present, that the different motions and
figures, bulk and number, of such particles, affecting the several organs
of our senses, produce in us those different sensations which we have
from the colours and smells of bodies ; v. g., that a violet, by the im-
pulse of insensible particles of matter of peculiar figure and bulks,
and in different degrees and modifications of their motions, causes the
idea of the blue colour and sweet scent of that flower to be produced
in our minds ; it being no more impossible to conceive that God should
annex such ideas to such motions, with which they have no similitude,
than that he should annex the idea of pain to the motion of a piece of
steel dividing our flesh, with which that idea hath no resemblance.
14. What I have said concerning colours and smells may be un-
derstood also of taste and sounds, and other the like sensible qualities ;
which, whatever reality we by mistake attribute to them, are in truth
nothing in the objects themselves, but powers to produce various sensa-
tions in us, and depend on those primary qualities, viz., bulk, figure,
texture, and motion of parts, as I have said.
15. Ideas of primary Qualities are Resemblances; of secondary,
not. — From whence I think it easy to draw this observation, that the
ideas of primary qualities of bodies are resemblances of them, and their
patterns do really exist in the bodies themselves ; but the ideas produced
in us by these secondary qualities have no resemblance of them at all.
There is nothing like our ideas existing in the bodies themselves. They
are in the bodies we denominate from them, only a power to produce
those sensations in us ; and what is sweet, blue, or warm in idea, is but
the certain bulk, figure, and motion of the insensible parts in the bodies
themselves, which we call so.
1 6. Flame is denominated hot and light ; snow, white and cold ;
and manna, white and sweet, from the ideas they produce in us ; which
qualities are commonly thought to be the same in those bodies that
those ideas are in us, the one the perfect resemblance of the other, as
THE BEGINNING OF MODERN PHILOSOPHY 109
they are in a mirror; and it would by most men be judged very extrava-
gant, if one should say otherwise. And yet he that will consider that
the same fire that at one distance produces in us the sensation of warmth,
does at a nearer approach produce in us the far different sensation of
pain, ought to bethink himself what reason he has to say that this idea
of warmth, which was produced in him by the fire, is actually in the fire ;
and his idea of pain, which the same fire produced in him the same way,
is not in the fire. Why are whiteness and coldness in snow, and pain
not, when it produces the one and the other idea in us ; and can do nei-
ther but by the bulk, figure, number, and motion of its solid parts ?
17. The particular bulk, number, figure, and motion of the parts
of fire or enow are really in them, whether any one's senses perceive
them or not, and therefore they may be called real qualities, because
they really exist in those bodies ; but light, heat, whiteness, or coldness,
are no more really in them than sickness or pain is in manna. Take
away the sensation of them ; let not the eye see light or colours, nor the
ears hear sounds ; let the palate not taste, nor the nose smell ; and all
colours, tastes, odours, and sounds, as they are such particular ideas,
vanish and cease, and are reduced to their causes, i. e., bulk, figure, and
motion of parts.
1 8. A piece of manna of a sensible bulk is able to produce in us
the idea of a round or square figure; and by being removed from one
place to another, the idea of motion. This idea of motion represents it
as it really is in the manna moving; a circle or square are the same,
whether in idea or existence, in the mind or in the manna; and this
both motion and figure are really in the manna, whether we take notice
of them or no ; this everybody is ready to agree to. Besides, manna by
the bulk, figure, texture, and motion of its parts, has a power to produce
the sensations of sickness, and sometimes of acute pains or gripings in
us. That these ideas of sickness and pain are not in the manna, but effects
of its operations on us, and are nowhere when we feel them not, this
also every one readily agrees to. And yet men are hardly to be brought
to think that sweetness and whiteness are not really in manna, which are
but the effects of the operations of manna, by the motion, size, and figure
of its particles on the eyes and palate ; as the pain and sickness caused
by manna are confessedly nothing but the effects of its operations on
the stomach and guts by the size, motion, and figure of its insensible
parts, (for by nothing else can a body operate, as has been proved) ;
as if it could not operate on the eyes and palate, and thereby produce in
110 THE BEGINNING OF MODERN PHILOSOPHY
the mind particular distinct ideas, which in itself it has not, as well as
we allow it can operate on the guts and stomach, and thereby produce
distinct ideas, which in itself it has not. These ideas being all effects
of the operations of manna on several parts of our bodies, by the size,
figure, number, and motion of its parts ; why those produced by the eyes
and palate should rather be thought to be really in the manna, than those
produced by the stomach and guts ; or why the pain and sickness ideas
that are the effect of manna, should be thought to be nowhere when they
are not felt; and yet the sweetness and whiteness, effects of the same
manna on other parts of the body, by ways equally as unknown, should
be thought to exist in the manna, when they are not seen or tasted,
would need some reason to explain.
19. Ideas of primary Qualities are Resemblances; of secondary,
not. — Let us consider the red and white colours in porphyry: hinder
light from striking on it, and its colours vanish, it no longer produces
any such ideas in us ; upon the return of light it produces these appear-
ances on us again. Can any one think any real alterations are made
in the porphyry by the presence or absence of light, and that those ideas
of whiteness or redness are really in porphyry in the light, when it is
plain it has no colour in the dark ? It has, indeed, such a configuration
of particles, both night and day, as are apt, by the rays of light rebound-
ing from some parts of that hard stone, to produce in us the idea of
redness, and from others the idea of whiteness ; but whiteness or redness
are not in it at any time, but such a texture that hath the power to pro-
duce such a sensation in us.
20. Pound an almond, and the clear white colour will be al-
tered into a dirty one, and the sweet taste into an oily one. What real
alteration can the beating of the pestle make in any body, but an altera-
tion of the texture of it?
21. Ideas being thus distinguished and understood, we may be
able to give an account how the same water, at the same time, may pro-
duce the idea of cold by one hand and of heat by the other; whereas
it is impossible that the same water, if those ideas were really in it,
should at the same time be both hot and cold ; for if we imagine warmth,
as it is in our hands, to be nothing but a certain sort and degree of mo-
tion in the minute particles of our nerves or animal spirits, we may un-
derstand how it is possible that the same water may, at the same time,
produce the sensations of heat in one hand and cold in the other ; which
yet figure never does, that never producing the idea of a square by one
THE BEGINNING OF MODERN PHILOSOPHY 111
hand which has produced the idea of a globe by another. But if the
sensation of heat and cold be nothing but the increase or diminution
of the motion of the minute parts of our bodies, caused by the corpus-
cles of any other body, it is easy to be understood, that if that motion
be greater in one hand than in the other, if a body be applied to the two
hands, which has in its minute particles a greater motion than in those
of one of the hands, and a less than in those of the other, it will increase
the motion of the one hand and lessen it in the other, and so cause the
different sensations of heat and cold that depend thereon.
22. I have in what just goes before been engaged in physical in-
quiries a little further than perhaps I intended; but it being necessary
to make the nature of sensation a little understood, and to make the
difference between the qualities in bodies, and the ideas produced by
them in the mind, to be distinctly conceived, without which it were im-
possible to discourse intelligently of them, I hope I shall be pardoned
this little excursion into natural philosophy, it being necessary in our
present inquiry to distinguish the primary and real qualities of bodies
which are always in them, (viz., solidity, extension, figure, number, and
motion, or rest, and are sometimes perceived by us, viz., when the bodies
they are in are big enough singly to be discerned,) from those secondary
and imputed qualities which are but the powers of several combinations
of those primary ones, when they operate without being distinctly dis-
cerned ; whereby we may also come to know what ideas are, and what
are not, resemblances of something really existing in the bodies we de-
nominate from them.
23. Three Sorts of Qualities in Bodies. — The qualities, then, that
are in bodies, rightly considered, are of three sorts.
First, the bulk, figure, number, situation, and motion or rest of
their solid parts ; those are in them, whether we perceive them or not ;
and when they are of that size that we can discover them, we have by
these an idea of the thing as it is in itself, as is plain in artificial things.
These I call the primary qualities.
Secondly, the power that is in any body, by reason of its insensible
primary qualities, to operate after a peculiar manner on any of our
senses, and thereby produce in us the different ideas of several colours,
sounds, smells, tastes, etc. These are usually called sensible qualities.
Thirdly, the power that is in any body, by reason of the particular
constitution of its primary qualities, to make such a change in the bulk,
figure, texture, and motion of another body, as to make it operate on
112 THE BEGINNING OP MODERN PHILOSOPHY
our senses differently from what it did before. Thus the sun has a
power to make wax white, and fire to make lead fluid. These are usu-
ally called powers.
The first of these, as has been said, I think may be properly called
real, original, or primary qualities, because they are in the things them-
selves, whether they are perceived or not ; and upon their different mod-
ifications it is that the secondary qualities depend.
The other two are only powers to act differently upon other things,
which powers result from the different modifications of those primary
qualities.
24. The first are Resemblances; the second thought Resemblances,
but are not; the third neither are, nor are thought so. — But though the
two latter sorts of qualities are powers barely, and nothing but powers,
relating to several other bodies, and resulting from the different modifi-
cations of the original qualities, yet they are generally otherwise thought
of; for the second sort, viz., the powers to produce several ideas in us
by our senses, are looked upon as real qualities in the things thus affect-
ing us ; but the third sort are called and esteemed barely powers ; e. g.,
the idea of heat or light, which we receive by our eyes or touch from
the sun, are commonly thought real qualities existing in the sun, and
something more than mere powers in it. But when we consider the sun
in reference to wax, which it melts or blanches, we look on the white-
ness and softness produced in the wax, not as qualities in the sun, but
effects produced by powers in it; whereas, if rightly considered, these
qualities of light and warmth, which are perceptions in me when I am
warmed or enlightened by the sun, are no otherwise in the sun, than
the changes made in the wax, when it is blanched or melted, are in the
sun. They are all of them equally powers in the sun, depending on its
primary qualities ; whereby it is able, in the one case, so to alter the bulk,
figure, texture, or motion of some of the insensible parts of my eyes
or hands, as thereby to produce in me the idea of light or heat ; and in
the other, it is able to so alter the bulk, figure, texture, or motion of
the insensible parts of the wax, as to make them fit to produce in me the
distinct ideas of white and fluid.
25. The reason why the one are ordinarily taken for real qualities,
and the other only for bare powers, seems to be, because the ideas
we have of distinct colours, sounds, etc., containing nothing at all in
them of bulk, figure, or motion, we are not apt to think them the effects
of these primary qualities, which appear not, to our senses, to operate
THE BEGINNING OF MODERN PHILOSOPHY 113
in their production, and with which they have not any apparent con-
gruity or conceivable connexion. Hence it is that we are so forward to
imagine that those ideas are the resemblances of something really ex-
isting in the objects themselves; since sensation discovers nothing of
bulk, figure, or motion of parts in their production ; nor can reason show
how bodies, by their bulk, figure, and motion, should produce in the
mind the ideas of blue or yellow, etc. But in the other case, in the oper-
ations of bodies, changing the qualities one of another, we plainly dis-
cover that the quality produced hath commonly no resemblance with
anything in the thing producing it; wherefore we look on it as a bare
effect of power. For though receiving the idea of heat or light from
the sun, we are apt to think it is a perception and resemblance of such
a quality in the sun ; yet when we see wax, or a fair face, receive changes
of colour from the sun, we cannot imagine that to be the reception or
resemblance of anything in the sun, because we find not those different
colours in the sun itself. For our senses being able to observe a likeness
or unlikeness of sensible qualities in two different external objects, we
forwardly enough conclude the production of any sensible quality in any
subject to be an effect of bare power, and not the communication of any
quality, which was really in the efficient, when we find no such sensible
quality in the thing that produced it; but our senses not being able to
discover any unlikeness between the idea produced in us, and the qual-
ity of the object producing it, we are apt to imagine that our ideas
are resemblances of something in the objects, and not the effects of
certain powers placed in the modification of their primary qualities, with
which primary qualities the ideas produced in us have no resemblance.
26. Secondary Qualities twofold; first, immediately perceivable;
secondly, mediately perceivable. — To conclude, beside those before-men-
tioned primary qualities in bodies, viz., bulk, figure, texture, number,
and motion of their solid parts, all the rest whereby we take notice of
bodies, and distinguish them one from another, are nothing else but sev-
eral powers in them depending on those primary qualities, whereby they
are fitted, either by immediately operating on our bodies, to produce
several different ideas in us, or else, by operating on other bodies, so to
change their primary qualities as to render them capable of producing
ideas in us different from what they did before. The former of these,
I think, may be called secondary qualities, immediately perceivable ; the
latter, secondary qualities, mediately perceivable.
114 THE BEGINNING OF MODERN PHILOSOPHY
SUBSTANCE
OF OUR COMPLEX IDEAS OF SUBSTANCES
1. Ideas of Substances, how made. — The mind being, as I have
declared, furnished with a great number of the simple ideas conveyed
in by the senses, as they are found in exterior things, or by reflection on
its own operations, takes notice also -that a certain number of these
simple ideas go constantly together ; which being, presumed to belong to
one thing, and words being suited to common apprehensions and made
use of for quick dispatch, are called, so united in one subject, by one
name ; which, by inadvertency, we are apt afterward to talk of and con-
sider as one simple idea, which indeed is a complication of many ideas
together ; because, as I have said, not imagining how these simple ideas
can subsist by themselves, we accustom ourselves to suppose some sub-
stratum wherein they do subsist, and from which they do result ; which
therefore we call substance.
2. Our Idea of Substance in general. — So that if any one will
examine himself concerning his notion of pure substance in general,
he will find he has no other idea of it at all, but only a supposition of he
knows not what support of such qualities which are capable of produc-
ing simple ideas in us ; which qualities are commonly called accidents.
If any one should be asked, what is the subject wherein colour or weight
inheres, he would have nothing to say, but the solid extended parts ; and
if he were demanded what is it that solidity and extension adhere in,
he would not be in a much better case than the Indian before mentioned,
who, saying that the world was supported by a great elephant, was asked
what the elephant rested on ; to which his answer was — a great tortoise.
But being again pressed to know what gave support to the broad-backed
tortoise, replied — something, he knew not what. And thus here, as in
all other cases where we use words without having clear and distinct
ideas, we talk like children ; who being questioned what such a thing is,
which they know not, readily give this satisfactory answer, that it is
something: which in truth signifies no more, when so used either by
children or men, but that they know not what ; and that the thing they
pretend to know and talk of, is what they have no distinct idea of at
all, and so are perfectly ignorant of it, and in the dark. The idea then
we have, to which we give the general name substance, being nothing
THE BEGINNING OF MODERN PHILOSOPHY 115
but the supposed but unknown support of those qualities we find exist-
ing, which we imagine cannot subsist, "sine re substante," without
something to support them, we call that support substantia; which, ac-
cording to the true import of the word, is in plain English, standing un-
der or upholding.
3. Of the Sorts of Substances. — An obscure and relative idea of
substance in general being thus made, we come to have the ideas of par-
ticular sorts of substances, by collecting such combinations of simple
ideas as are, by experience and observation of men's senses, taken notice
of to exist together, and .are therefore supposed to flow from the par-
ticular internal constitution, or unknown essence of that substance.
Thus we come to have the ideas of a man, horse, gold, water, etc., of
which substances, whether any one has any other clear idea, further
than of simple ideas coexistent together, I appeal to every one's own
experience. It is the ordinary qualities observable in iron, or a diamond,
put together, that make the true complex idea of those substances, which
a smith or jeweller commonly knows better than a philosopher; who,
whatever substantial form he may talk of, has no other idea of those sub-
stances, than what is framed by a collection of those simple ideas which
are to be found in them ; only we must take notice, that our complex
ideas of substances, besides all those simple ideas they are made up of,
have always the confused idea of something to which they belong and
in which they subsist. And therefore when we speak of any sort of sub-
stance, we say it is a thing having such or such qualities ; as body is a
thing that is extended, figured, and capable of motion ; spirit, a thing
capable of thinking ; and so hardness, friability, and power to draw iron,
we say, are qualities to be found in a loadstone. These, and the like
fashions of speaking, intimate that the substance is supposed always
something besides the extension, figure, solidity, motion, thinking, or
other observable ideas, though we know not what it is.
4. No clear idea of Substance in general. — Hence, when we talk
or think of any particular sort of corporeal substances, as horse, stone,
etc., though the idea we have of either of them be but the complication
or collection of those several simple ideas of sensible qualities, which we
used to find united in the thing called horse or stone; yet, because we
cannot conceive how they should subsist alone, nor one in another, we
suppose them existing in and supported by some common subject ; which
support we denote by the name substance, though it be certain we have
no clear or distinct idea of that thing we suppose a support.
116 THE BEGINNING OF MODERN PHILOSOPHY
5. As clear an Idea of Spirit as Body. — The same thing happens
concerning the operations of the mind, viz., thinking, reasoning, fearing,
etc., which we concluding not to subsist of themselves, nor apprehend-
ing how they can belong to body, or be produced by it, we are apt to
think these the actions of some other substance, which we call spirit;
whereby yet it is evident that, having no other idea or notion of matter,
but something wherein those many sensible qualities which affect our
senses do subsist ; by supposing a substance wherein thinking, knowing,
doubting, and a power of moving, etc., do subsist, we have as clear a
notion of its substance of spirit, as we have of body : the one being sup-
posed to be (without knowing what it is) the substratum to those simple
ideas we have from without; and the other supposed (with a like igno-
rance of what it is) to be the substratum to those operations we experi-
ment in ourselves within. It is plain then, that the idea of corporeal
substance in matter is as remote from our conceptions and apprehen-
sions, as that of spiritual substance or spirit; and therefore, from our
not having any notion of the substance of spirit, we can no more con-
clude its non-existence, than we can, for the same reason, deny the ex-
istence of body ; it being as rational to affirm there is no body, because
we have no clear and distinct idea of the substance of matter, as to say
there is no spirit, because we have no clear and distinct idea of the sub-
stance of a spirit.
117
SEVENTEENTH CENTURY NATURAL SCIENCE
FROM THE CHRISTIANIZATION of Europe in the early Middle Ages
to the end of the Thirty Years' War in 1648, the most important sub-
jects for thought were religious. The great minds of Europe mostly
spent their efforts on this field. With the discovery of America in 1492
came the first great break in the old order of things. The beginning of
modern natural science was made by Copernicus, Galileo, Kepler, and
Bacon, and from the middle of the seventeenth century, the growth of
the natural sciences has been so rapid that they now constitute by far the
greater part of that legacy from generation to generation which we call
the world's knowledge.
Before looking at the work itself of the scientists of the seventeenth
century, it will give us a better bird's-eye view of the development of
tne subject to run over the chief advances of the period.
The ideas of Galileo, Kepler and Bacon, whose work made mem-
orable the first of the seventeenth century, have already been noted in
a previous volume.
Harvey in 1619 founded physiology by demonstrating the circula-
tion of the blood. Soon afterwards (in 1622) Asellius discovered the
lacteal circulation, and in 1649 Olaiis Riidbeck of Sweden found that
these lacteals or lymphatics furnished the thoracic duct, and thus the
heart, with the material for new blood. In 1690 Van Leeuwenhoeck
strengthened Harvey's theory by discovering the capillary circulation
of the blood from the arteries to the veins.
In physics, the advances were many and great. Torricelli in-
vented the barometer (1644) and Pascal (1656) by showing that the
118 SEVENTEENTH CENTURY NATURAL SCIENCE
mercury rises to different heights at different altitudes above the earth,
proved that it is the weight of the air which causes the rise of the mer-
cury. Guericke in 1650 invented the air pump and in 1672 the first
electrical machine. Newton proved the compound nature of light in
1666-71. Roemer in 1676 estimated its velocity by noting the difference
in the apparent time of the eclipses of Jupiter's moons, depending upon
whether the earth is upon the side of its orbit nearest or farthest from
Jupiter. The greatest variation observed was 16 minutes and 36 sec-
onds, or 996 seconds, and the diameter of the earth's orbit was thought
to be about 190,000,000 miles. Light would then travel about 190,000
miles in a second. Huyghens took up the question of the nature of light
and in 1678 developed his wave theory and his conception of ether as
the medium through which light moves. In 1682 Newton worked out
his law of gravitation and showed that weight is the result of an attrac-
tive force between masses of matter, that acts throughout all the im-
mensity of the solar system.
A first foundation was laid in biology. Malphigi making use of the
microscope discovered the capillaries between the ends of the arteries
and the veins, the air-cells in the lungs, the color cells beneath the outer
layer of the skin, and along with Grew in 1670 began modern botany by
pointing out the cell-system in plants and that flowers differ in sex anal-
ogously with animals. In 1677 Leeuwenhoeck discovered the animalcu-
lae in water, thus opening up a vast world of microscopic life hitherto
undreamed of, in 1690 the actual capillary circulation, and made many
important investigations on insect-anatomy.
In chemistry, which began to break away from alchemy, Boyle dis-
covered that gases are compressed practically in proportion to the pres~
sure upon them (about 1665). Mayow in 1674 demonstrated that there
is some component in the air necessary for breathing and combustion,
but his discovery had to be remade a hundred years later.
Thus the seventeenth century saw the work of the world's greatest
astronomers, the foundation of physiology, the great law of gravitation,
the first interpretation of sensation — light and sound — in terms of mo-
tion, the first law in chemistry, and the first insight into the world re-
vealed by the microscope.
119
ANTHONY VON LEEUWENHOECK
ANTHONY VON LEEUWENHOECK was born at Delft, Holland, 1632.
His trade was that of lens-maker for microscopes, and his scientific spirit
led him from this into researches with the instruments he made.
He made several great discoveries and many others of less impor-
tance. In 1673 he noticed the red globules in the blood. In 1675 he dis-
covered the animalculae in water, thus making a first beginning in bac-
teriology. He first described the spermatazoa in 1677. In 1690 he
traced the passage of the blood from the arteries into the veins by the
capillaries, thus filling in the gap in Harvey's theory. He also noted the
tubules of teeth, the solidity of hair, the structure of the epidermis. His
descriptions of the anatomy of insects are classical. In theoretical biol-
ogy he stood for the idea that everything generated its kind, and against
spontaneous generation. Outside of his scientific studies his life was
uneventful. Most of his discoveries were announced to the Royal So-
ciety of London. He died in 1723.
OBSERVATIONS ON ANIMALCULA SEEN IN RAIN, WELL,
SEA AND SNOW-WATER; AS ALSO IN PEPPER- WATER
In the year 1675, I discovered very small living creatures in rain
water, which had stood but few days in a new earthen pot glazed blue
within. This invited me to view this water with great attention, espe-
cially those little animals appearing to me ten thousand times less than
those represented by M. Swammerdam, and by him called water-fleas,
or water-lice, which may be perceived in the water with the naked eye.
The first sort I several times observed to consist of 5, 6, 7, or 8
clear globules without being able to discern any film that held them to-
gether, or contained them. When these animalcula or living atoms
moved, they put forth two little horns, continually moving. The space
between these two horns was flat, though the rest of the body was
roundish, sharpening a little towards the end, where they had a tail,
120 SEVENTEENTH CENTURY NATURAL SCIENCE
near four times the length of the whole body, of the thickness, by my
microscope, of a spider's web ; at the end of which appeared a globule
of the size of one of those which made up the body. These little crea-
tures, if they chanced to light on the least filament or string, or other
particle, were entangled therein, extending their body in a long round,
and endeavoring to disentangle their tail. Their motion of extension
and contraction continued a while; and I have seen several thousands
of these poor little creatures, within the space of a grain of gross sand,
lie fast clustered together in a few filaments.
I also discovered a second sort, of an oval figure ; and I imagined
their head to stand on a sharp end. These were a little longer than the
former. The inferior part of their body is flat, furnished with several
extremely thin feet, which moved very nimbly. The upper part of the
body was round, and had within 8, 10, or 12 globules, where they were
very clear. These little animals sometimes changed their figure into a
perfect round, especially when they came to lie on a dry place. Their
body was also very flexible ; for as soon as they struck against any the
smallest fibre or string, their body was bent in, which bending presently
jerked out again. When I put any of them on a dry place, I observed
that, changing themselves into a round, their body was raised pyramidal-
wise, with an extant point in the middle ; and having laid thus a little
while, with a motion of their feet, they burst asunder, and the globules
were presently diffused and dissipated, so that I could not discern the
least thing of any film, in which the globules had doubtless been en-
closed ; and at this time of their bursting asunder, I was able to discover
more globules than when they were alive.
I observed a third sort of little animals, that were twice as long as
broad, and to my eye eight times smaller than the first. Yet I thought
I discerned little feet, whereby they moved very briskly, both in round
and straight line.
There was a fourth sort, which were so small that I was not able
to give them any figure at all. These were a thousand times smaller than
the eye of a large louse. These exceeded all the former in celerity. I
have often observed them to stand still as it were on a point, and then
turn themselves about with that swiftness, as we see a top turn round,
the circumference they made being no larger than that of a grain of
small sand, and then extending themselves straight forward, and by and
by lying in a bending posture. I discovered also several other sorts of
SEVENTEENTH CENTURY NATURAL SCIENCE 121
animals ; these were generally made up of such soft parts, as the former,
that they burst asunder as soon as they came to want water.
May 26, it rained hard; the rain growing less, I caused some of
that rain-water running down from the house top, to be gathered in a
clean glass, after it had been washed two or three times with water.
And in this I observed some few very small living creatures, and seeing
them, I thought they might have been produced in the leaded gutters in
some water that had remained there before.
I perceived in pure water, after some days, more of those animals,
as also some that were somewhat larger. And I imagine, that many
thousands of these little creatures do not equal an ordinary grain of
sand in bulk; and comparing them with a cheese-mite, which may be
seen to move with the naked eye, I make the proportion of one of these
small water-creatures to a cheese-mite to be like that of a bee to a horse ;
for, the circumference of one of these little animals in water is not so
large as the thickness of a hair in a cheese-mite.
In another quantity of rain-water, exposed for some days to the
air, I observed some thousands of them in a drop of water, which were
of the smallest sort that I had seen hitherto. And in some time after I
observed, besides the animals already noted, a sort of creatures that
were eight times as large, of almost a round figure ; and as those very
small animalcula swam gently among each other, moving as gnats do in
the air, so did these larger ones move far more swiftly, tumbling round
as it were, and then making a sudden downfall.
In the waters of the river Maese I saw very small creatures of
different kinds and colours, and so small, that I could very hardly dis-
cern their figures ; but the number of them was far less than those found
in rain-water. In the water of a very cold well in the autumn, I dis-
covered a very great number of living animals very small, that were ex-
ceedingly clear, and a little larger than the smallest I ever saw. In sea
water I observed at first, a little blackish animal, looking as if it had
been made up of two globules. This creature had a peculiar motion,
resembling the skipping of a flea on white paper, so that it might very
well be called a water-flea ; but it was far less than the eye of that little
animal, which Dr. Swammerdam calls the water-flea. I also discovered
little creatures therein that were clear, of the same size with the former
animal, but of an oval figure, having a serpentine motion. I further
noticed a third sort, which were very slow in their motion; their body
was of a mouse colour, clear towards the oval point; and before the
V 6-8
123 SEVENTEENTH CENTURY NATURAL SCIENCE
head and behind the body there stood out a sharp little point angle-wise.
This sort was a little larger. But there was yet a fourth somewhat
longer than oval. Yet of all these sorts there were but a few of each.
Some days after viewing this water, I saw 100 where before I had seen
but one; but these were of another figure, and not only less, but they
were also very clear, and of an oblong oval figure, only with this dif-
ference, that their heads ended sharper ; and although they were a thou-
sand times smaller than a small grain of sand, yet when they lay out
of the water in a dry place, they burst in pieces and spread into three
or four very little globules, and into some aqueous matter, without any
other parts appearing in them.
Having put about one-third of an ounce of whole pepper in water,
and it having lain about three weeks in the water, to which I had twice
added some snow-water, the other water being in great part exhaled;
I discerned in it with great surprise an incredible number of little ani-
mals, of divers kinds, and among the rest, some that were three or four
times as long as broad ; but their whole thickness did not much exceed
the hair of a louse. They had a very pretty motion, often tumbling
about and sideways ; and when the water was let to run off from them,
they turned round like a top ; at first their body changed into an oval,
and afterwards, when the circular motion ceased, they returned to their
former length. The second sort of creatures discovered in this water,
were of a perfect oval figure, and they had no less pleasing or nimble a
motion than the former ; and these were in far greater numbers. There
was a third sort, which exceeded the two former in number, and these
had tails like those I had formerly observed in rain-water. The fourth
sort, which moved through the three former sorts, were incredibly small,
so that I judged, that if 100 of them lay one by another, they would not
equal the length of a grain of coarse sand ; and according to this esti-
mate, 1,000,000 of them could not equal the dimensions of a grain of
such coarse sand. There was discovered a fifth sort, which had near
the thickness of the former, but almost twice the length.
In snow-water, which had been about three years in a glass bottle
well stopped, I could discover no living creatures ; and having poured
some of it into a porcelain tea-cup, and put therein half an ounce of
whole pepper, after some days I observed some animalcula, and those
exceedingly small ones, whose body seemed to me twice as long as
broad, but they moved very slowly, and often circularly. I observed also
SEVENTEENTH CENTURY NATURAL SCIENCE 123
a vast multitude of oval-figured animalcula, to the number of 6,000 or
8,000 in a single drop. — Transactions of the Royal Society.
NEWTON
SIR ISAAC NEWTON was born at Woolstrop, Lincolnshire, England,
Dec. 25, 1642 (O. S.). His father, a farmer of good descent, had died
before he was born. He attended the free grammar school at Grantham,
but left early. His ability in making mechanical toys, however, brought
his mother to return him to school, and later send him to Cambridge.
He took his degree in 1665, in 1667 was made a fellow of the university,
and in 1669 professor of mathematics. He had already discovered his
method of fluxions, which closely resembles Leibnitz's Differential Cal-
culus, invented about the same time.
In 1672 he was elected a member of the Royal Society and soon
afterwards sent to them his communication concerning how he had
broken up light by means of a prism, thus showing the compound nature
of the sun's rays.
In 1682 a new measurement of the meridian was brought to his
notice. Sixteen years before he had conceived the idea of universal
gravity and had calculated the pull the earth would exert on the moon
in accordance with its supposed mass. The result had not agreed with
the speed of revolution of the moon and Newton had laid the hypothesis
aside. He saw that the new calculation of the size of the earth was
in the right direction and set to work at a re-calculation of the problem.
The solution is given below.
When he saw that the hypothesis of a universal attraction between
masses was coming close to agreeing with the known facts, he was so
agitated that he had to ask a friend to complete it for him.
Some years later he began to investigate chemistry, but the story
is that his papers were destroyed by his dog and he never quite recov-
ered from the shock. From 1695 to 1699 he was warden of the mint,
and from 1699 to his death master of the mint, a place paying from
$6,000 to $9,000 a year.
He died March 20, 1727. His discoveries in light, in gravitation,
124 SEVENTEENTH CENTURY NATURAL SCIENCE
including the universal theory and its application to the planets and
the tides, or in mathematics would any one of them make his name de-
serving of immortality.
THE DIFFUSION OF LIGHT
A letter of Mr. Isaac Newton, Professor of Mathematics in the
University of Cambridge ; containing his new theory of Light and Col-
ours ; sent by the Author to the Editor from Cambridge, Feb. 6, 1671-3 ;
to be communicated to the Royal Society. No. 80, p. 3,075.
SIR — To perform my late promise to you, I shall without further
ceremony acquaint you that in the beginning of the year 1666 (at which
time I applied myself to the grinding of optic glasses of other figures
than spherical,) I procured a triangular glass prism, to try therewith the
celebrated phenomena of colours. And for that purpose, having dark-
ened my chamber, and made a small hole in my window shuts, to let in
a convenient quantity of the sun's light, I placed my prism at this
entrance, that it might be thereby refracted to the opposite wall. It was
at first a very pleasing diversion to view the vivid and intense colours
produced thereby ; but after a while applying myself more circumspectly,
I was surprised to see them in an oblong form ; which according to the
received laws of refraction, I expected would have been circular. They
were terminated at the sides with straight lines, but at the ends the
decay of light was so gradual, that it was difficult to determine justly
what was their figure ; yet they seemed semicircular.
Comparing the length of this coloured spectrum with its breadth, I
found it about five times greater; a disproportion so extravagant, that
it excited me to a more than ordinary curiosity of examining from
whence it might proceed. I could scarce think that the various thick-
ness of the glass, or the termination with shadow or darkness, could
have any influence on light to produce such an effect ; yet I thought it
not amiss, first to examine those circumstances, and so tried what would
happen by transmitting light through parts of the glass of divers thick-
nesses, or through holes in the window of divers sizes, or by setting the
prism without, so that the light might pass through it, and be refracted
before it was terminated by the hole; but I found none of these cir-
cumstances material. The fashion of the colours was in all these cases
the same.
SIR ISAAC NEWTON
Engrawng /rom an original picture by Vanderbank.
j*ll%' *N1 KENTH CENTCRY NATUfc> :E
\mg the universal theory and its app^cntl^ '•* $fc|Mte and
des, or in mathematics would any one of them v.^s *>*•> ntmc de-
jg of immortality.
THE DIFFUSION OF
A letter of Mr. Isaac Newtnui. ! >hwr>atics ir.
University of Cambridge: rortai* •• v-
At wh*ch
«fHic glasses of other figures
v ..<»,-««- -iiass prism, to try therewith the
c-.'icbratetj p!-< 'na of coi And for that purpose, having dark-
ened my chamber, and made a small hole in my window shuts, to let in
a convenient quantity of the sun's light, I placed my prism at this
r.ce. that it nii.^hy^-j^^^v-ij^igjTr^j^o the opposite wall. It was
at li'-st a v*rv (-'.ra^n diversion to view the vivid and intense colours
jsrv turtosity of examining from
\ c*?ul'J scarce think that the various thick-
ur^i .-..i tbv ^'iavs. or th^ termination with shadow or darkness, could
have any intltience on light to produce such an effect; yet I thought it
not amiss, first to examine those circumstances, and &> tried what w^jtild
happen by transmitting light through parts of it- "r* thick-
or thruuerh holes in the window of diver* *»*/**. -:»r S>
M"X€ H was frrniuated by the hole; but «:ir-
i'ashioit
SEVENTEENTH CENTURY NATURAL SCIENCE 125
Then I suspected, whether by any imevenness in the glass, or other
contingent irregularity, these colours might be thus dilated. And to try
this, I took another prism like the former, and so placed it, that the
light passing through them both, might be refracted contrary ways, and
so by the latter returned into that course from which the former had
diverted it. For, by this means, I thought the regular effects of the first
prism would be destroyed by the second, but the irregular ones more
augmented, by the multiplicity of refractions. The event was, that the
light, which by the first prism was diffused into an oblong form, was
by the second reduced into an orbicular one, with as much regularity as
when it did not at all pass through them. So that, whatever was the
cause of that length, it was not any contingent irregularity.
I then proceeded to examine more critically, what might be effected
by the difference of the incidence of rays coming from divers parts of
the sun ; and to that end measured the several lines and angles, belong-
ing to the image. Its distance from the hole or prism was 2.2 feet ; its
utmost length 13^ inches; its breadth 2f ; the diameter of the hole J of
an inch ; the angle, which the rays, tending towards the middle of the
image, made with those lines in which they would have proceeded with-
out refraction, was 44° 56'. And the vertical angle of the prism,
63° 12'. Also the refraction on both sides the prism, that is of the in-
cident and emergent rays, was as near as I could make them equal, and
consequently about 54° 4'. And the rays fell perpendicularly upon the
wall. Now subducting the diameter of the hole from the length and
breadth of the image, there remains 13 inches the length, and 2§ the
breadth, comprehended, by those rays, which passed through the center
of the said hole, and consequently the angle of the hole, which that
breadth subtended, was about 31', answerable to the sun's diameter; but
the angle which its length subtended, was more than five such diameters,
namely 2° 49'.
Having made these observations, I first computed from them the
refractive power of that glass, and found it measured by the ratio of the
sizes, 20 to 31. And then, by that ratio, I computed the refraction of
two rays flowing from opposite parts of the sun's discus, so as to differ
31' in their obliquity of incidence, and found that the emergent rays
should have comprehended an angle of about 31', as they did, before
they were incident. But because this computation was founded on the
hypothesis of the proportionality of the sines of incidence and refrac-
tion, which though, by own experience, I could not imagine to be so
123 SEVENTEENTH CENTURY NATURAL SCIENCE
erroneous as to make that angle but 31', which in reality was 2° 49'; yet
my curiosity caused me again to take my prism. And having placed it at
ray window, as before, I observed, that by turning it a little about its
axis to and fro, so as to vary its obliquity to the light, more than an
angle of 4 or 5 degrees, the colours were not thereby sensibly translated
from their place on the wall, and consequently by that variation of
incidence, the quantity of refraction was not sensibly varied. By this
experiment, therefore, as well as by former computation, it was evident,
that the difference of the incidence of rays, flowing from divers parts
of the sun, could not make them after a decussion, diverge at a sensibly
greater angle, than that at which they before converged, which being at
most but about 21 or 32 minutes, there still remained some other cause
to be found out, from whence it could be 2° 49'.
Then I began to suspect whether the rays, after their trajection
through the prism, did not move in curve lines, and according to their
more or less curvity tend to divers parts of the wall. And it increased
my suspicion, when I remembered that I had often seen a tennis ball,
struck with an oblique racket, describe such a curve line. For, a cir-
cular as well as a progressive motion being communicated to it by that
.stroke, its parts on that side, where the motions conspire, must press
and beat the contiguous air more violently than on the other, and there
excite a reluctancy and reaction of the air proportionately greater. And
for the same reason, if the rays of light should possibly be globular bod-
ies, and by their oblique passage out of one medium into another acquire
a circulating motion, they ought to feel the greater resistance from the
ambient aether, on that side where the motions conspire, and thence be
continually bowed to the other. But notwithstanding this plausible
ground of suspicion, when I came to examine it, I could observe no such
curvity in them. And besides (which was enough for my purpose) I
observed, that the difference between the length of the image and the
diameter of the hole, through which the light was transmitted, was pro-
portionable to their distance.
The gradual removal of these suspicions at length led me to the
experimentum crucis, which was this; I took two boards, and placed
one of them close behind the prism at the window, so that the light
might pass through a small hole, made in it for that purpose, and fall on
the other board, which I placed at about 12 feet distance, having first
made a small hole in it also, for some of that incident light to pass
through. Then I placed another prism behind this second board, so that
SEVENTEENTH CENTURY NATURAL SCIENCE 127
the light trajected through both of the boards, might pass through that
also, and be again refracted before it arrived at the wall. This done, I
took the first prism in my hand, and turned it to and fro slowly about
its axis, so much as to make the several parts of the image, cast on the
second board, successively pass through the hole in it, that I might ob-
serve to what places on the wall the second prism would refract them.
And I saw, by the variation of those places, that the light tending to
that end of the image, towards which the refraction of the first prism
was made, did in the second prism suffer a contraction considerably
greater than the light tending to the other end. And so the true cause
of the length of that image was detected to be no other, than that light
consists of rays differently refrangible, which, without any respect to a
difference in their incidence, were according to their degrees of refran-
gibility, transmitted towards divers parts of the wall.
When I understood this, I left off my aforesaid glass works ; for I
saw, that the perfection of telescopes was hitherto limited, not so much
for want of glasses truly figured according to the prescriptions of optic
authors, (which all men have hitherto imagined) as because that light
itself is a heterogeneous mixture of differently refrangible rays. So
that, were a glass so exactly figured, as to collect any one sort of rays
into one point, it could not collect those also into the same point, which
having the same incidence upon the same medium are apt to suffer
a different refraction. Nay, I wondered, that seeing the difference of
refrangibility was so great, as I found it, telescopes should arrive to
that perfection they are now at. For measuring the refractions in any
one of my prisms, I found, that supposing the common sine of incidence
upon one of its planes was 44 parts, the sine of refraction of the utmost
rays at the red end of the colours, made out of the glass into the air,
would be 68 parts, and the sine of refraction of the utmost rays on the
other end 69 parts ; so that the difference is about a 24th or 25th part of
the whole refraction ; and consequently the object glass of any telescope
cannot collect all the rays which come from one point of an object, so
as to make them convene at its focus in less room than in a circular
space, whose diameter is the 5oth part of the diameter of its aperture ;
which is an irregularity, some hundreds of times greater than a circu-
larly fixed lens, of so small a section as the object glasses of long tele-
scopes are, would cause by the unfitness of its figure, were light uniform.
This made me take reflections into consideration, and finding them
regular, so that the angle of reflection of all sorts of rays was equal to
128 SEVENTEENTH CENTURY NATURAL SCIENCE
their angle of incidence ; I understood that by their mediation optic in-
struments might be brought to any degree of perfection imaginable, pro-
vided a reflecting substance could be found, which would polish as finely
as glass, and reflect as much light as glass transmits, and the art of com-
municating to it a parabolic figure be also attained. But there seemed
very great difficulties, and I have thought them insuperable, when I fur-
ther considered, that every irregularity in a reflecting superficies makes
the rays stray 5 or 6 times more out of their due course, than the like
irregularities in a refracting one ; so that a much greater curiosity would
be here requisite, than in figuring glasses for refraction.
Amid these thoughts I was forced from Cambridge by the inter-
vening plague, and it was more than two years before I proceeded fur-
ther. But then having thought on a tender way of polishing, proper for
metal, whereby as I imagined, the figure also would be corrected to the
last ; I began to try what might be effected in this kind, and by degrees
so far perfected an instrument (in the essential parts of it like that I
sent to London,) by which I could discern Jupiter's 4 concomitants, and
showed them divers times to two others of my acquaintance. I could
also discern the moon-like phase of Venus, but not very distinctly, nor
without some niceness in disposing the instrument.
From that time I was interrupted till this last autumn, when I made
the other. And that was sensibly better than the first (especially for
day objects,) so I doubt not, but they will be still brought to a much
greater perfection by their endeavors, who, as you inform me, are taking
care about it at London.
I have sometimes thought to make a microscope, which in like man-
ner should have, instead of an object glass, a reflecting piece of metal.
And this I hope they will also take into consideration. For those instru-
ments seem as capable of improvement as telescopes, and perhaps more,
because but one reflective piece of metal is requisite in them, as you may
perceive by the diagram, (fig. 13, pi. 14,) where AB represents the
object metal, CD the eye glass, F their common focus, and O the other
focus of the metal, in which the object is placed.
But to return from this digression, I told you, that a light is not
similar, or homogeneal, but consists of difform rays, some of which are
more refrangible than others : so that of those, which are alike incident
on the same medium, some shall be more refracted than others, and that
not by any virtue of the glass, or other external cause, but from a pre-
SEVENTEENTH CENTURY NATURAL SCIENCE 129
disposition, which every particular ray has to suffer a particular degree
of refraction.
I shall now proceed to acquaint you with another more notable
difformity in its rays, wherein the origin of colours is unfolded ; concern-
ing which I shall lay down the doctrine first, and then, for its examina-
tion, give you an instance or two of experiments, as a specimen of the
rest. The doctrine you will find comprehended and illustrated in the
following propositions :
1. As the rays of light differ in degrees of refrangibility, so they
also differ in their disposition of light, derived from refractions, or
reflections of natural bodies (as it is generally believed,) but original
and connate properties, which in divers rays are diverse. Some rays
are disposed to exhibit a red colour, and no other : some a yellow, and
no other : some a green, and no other, and so of the rest. Nor are there
only rays proper and particular to the more eminent colours, but even to
all their intermediate gradations.
2. To the same degree of refrangibility ever belongs the same
colour, and to the same colour ever belongs the same degree of refran-
gibility. The least refrangible rays are all disposed to exhibit a red
colour, and contrarily, those rays which are disposed to exhibit a red
colour, are all the least refrangible : so the most refrangible rays are all
disposed to exhibit a deep violet-colour, and contrarily, those which are
apt to exhibit such a violet colour, are all the most refrangible. And so
to all the intermediate colours, in a continued series, belong intermedi-
ate degrees of refrangibility. And this analogy betwixt colours, and
refrangibility, is very precise and strict ; the rays always either exactly
agreeing in both, or proportionally disagreeing in both.
3. The species of colour and degree of refrangibility proper to any
particular sort of rays, is not mutable by refraction, nor by reflection
from natural bodies, nor by any other cause, that I could yet observe.
When any one sort of rays has been well parted from those of other
kinds, it has afterwards obstinately retained its colour, notwithstanding
my utmost endeavours to change it. I have refracted it with prisms,
and reflected it with bodies, which in daylight were of other colours ;
I have intercepted it with the coloured film of air interceding two com-
pressed plates of glass ; transmitted it through coloured mediums, and
through mediums irradiated with other sorts of rays, and diversely ter-
minated it ; and yet could never produce any new colour out of it. It
would by contracting or dilating, become more brisk, or faint, and by
130 SEVENTEENTH CENTURY NATURAL SCIENCE
the loss of many rays, in some cases very obscure and dark ; but I could
never see it change in specie.
4. Yet seeming transmutations of colours may be made, where
there is any mixture of divers sorts of rays. For in such mixtures, the
component colours appear not, but, by their mutual alloying each other,
constitute a middling colour. And therefore, if by refraction, or any
other of the aforesaid causes, the difform rays, latent in such a mixture,
be separated, there shall emerge colours different from the colour of the
composition. Which colours are not new generated, but only made ap-
parent by being parted ; for if they be again entirely mixed and blended
together, they will again compose that colour, which they did before
separation. And for the same reason, transmutations made by the con-
vening of divers colours are not real; for when the difform rays are
again severed, they will exhibit the very same colours, which they did
before they entered into composition ; as you see, blue and yellow pow-
ders, when finely mixed, appear to the naked eye green, and yet the
colours of the component corpuscles are not thereby really transmuted,
but only blended. For, when viewed with a good microscope, they still
appear blue and yellow interspersedly.
5. There are therefore two sorts of colours. The one original
and simple, the other compounded of these. The original or primary
colours are, red, yellow, green, blue, and a violet-purple, together with
orange, indigo, and an indefinite variety of intermediate gradations.
6. The same colours in specie with these primary ones may be also
produced by composition: for a mixture of yellow and blue makes
green ; of red and yellow makes orange ; of orange and yellowish green
makes yellow. And in general, if any two colours be mixed, which in
the series of those, generated by the prism, are not too far distant one
from another, they by their mutual alloy compound that colour, which
in the said series appears in the midway between them. But those which
are situated at too great a distance, do not so. Orange and indigo
produce not the intermediate green, nor scarlet and green the interme-
diate yellow.
7. But the most surprising and wonderful composition was that of
whiteness. There is no one sort of rays which alone can exhibit this.
It is ever compounded, and to its composition are requisite all the afore-
said primary colours, mixed in a due proportion. I have often with
admiration beheld, that all the colours of the prism being made to con-
verge, and thereby to be again mixed as they were in the light before it
SEVENTEENTH CENTURY NATURAL SCIENCE 131
was incident upon the prism, reproduced light, entirely and perfectly
white and not at all sensibly differing from a direct light of the sun,
unless when the glasses I used, were not sufficiently clear ; for then they
would a little incline it to their colour.
8. Hence it therefore comes to pass, that whiteness is the usual
colour of light : for, light is a confused aggregate of rays imbued with
all sorts of colours, as they are promiscuously darted from the various
parts of luminous bodies. And of such a confused aggregate, as I said,
is generated whiteness, if there be a due proportion of the ingredients,
but if any one predominate, the light must incline to that colour ; as it
happens in the blue flame of brimstone; the yellow flame of a candle;
and the various colours of the fixed stars.
9. These things considered, the manner how colours are produced
by the prism is evident. For, of the rays constituting the incident light,
since those which differ in colour, proportionally differ in refrangibility,
they by their unequal refractions must be severed and dispersed into an
oblong form in an orderly succession, from the least refracted scarlet, to
the most refracted violet. And for the same reason it is that objects,
when looked upon through a prism, appear coloured. For the difform
rays, by their unequal refractions, are made to diverge towards several
parts of the retina, and there express the images of things coloured, as in
the former case they did the sun's image upon the wall. And by this
inequality of refractions they became not only coloured, but also very
confused and indistinct.
10. Why the colours of the rainbow appear in falling drops of
rain, is also from hence evident. For, those drops which refract the
rays disposed to appear purple, in greatest quantity to the spectator's
eye, refract those of other sorts so much more, as to make them pass
beside it ; and such are the drops on the exterior part of the primary,
and interior part of the secondary bow.
11. The old phenomena of an infusion of lignum nephriticum,
leaf gold, fragments of coloured glass, and some other transparently
coloured bodies, appearing in one position of one colour, and of another
in another, are on these grounds no longer riddles. For, those are sub-
stances apt to reflect one sort of light, and transmit another; as may
be seen in a dark room, by illuminating them with similar or uncom-
pounded light. For, then they appear that colour only, with which
they are illuminated, but yet in one position more vivid and luminous
132 SEVENTEENTH CENTURY NATURAL SCIENCE
than in another, accordingly as they are disposed more or less to reflect
or transmit the incident colour.
12. From hence also is manifest the reason of an unexpected ex-
periment, which Mr. Hook, somewhere in his micography, relates to
have made with two wedge-like transparent vessels, filled the one with
red, the other with a blue liquor : namely, that though they were sever-
ally transparent enough, yet both together became opaque; for, if one
transmitted only red, and the other only blue, no rays could pass through
them both.
13. I might add more instances of this nature ; but I shall conclude
with this general one, that the colours of all natural bodies have no other
origin than this, that they are variously qualified to reflect one sort of
light in greater plenty than another. And this I have experimneted in
a dark room, by illuminating those bodies with uncompounded light of
divers colours. For, by that means, any body may be made to appear of
any colour. They have then no appropriate colour, but ever appear of
the colour of the light cast upon them, but yet with this difference, that
they are most brisk and vivid in the light of their own day-light colour.
Minium appears there of any colour indifferently, with which it is illus-
trated, but yet most luminous in red ; and so bise appears indifferently
of any colour with which it is illustrated, but yet most luminous in blue.
And therefore minium reflects rays of any colour, but most copiously
those indued with red ; and consequently when illustrated with daylight,
that is, with all sorts of rays promiscuously blended, those qualified with
red shall abound most in the reflected light, and by their prevalence
cause it to appear of that colour. And for the same reason bise, reflect-
ing blue most copiously, shall appear blue by the excess of those rays in
its reflected light; and the like of other bodies. And that this is the
entire and adequate cause of their colours, is manifest, because they have
no power to change or alter the colours of any sort of rays, incident
apart, but put on all colours indifferently, with which they are en-
lightened.
These things being so, it can be no longer disputed, whether there
be colours in the dark, nor whether they be the qualities of the objects
we see, no nor perhaps whether light be a body. For since colours are
the qualities of light, having its rays for their entire and immediate sub-
ject, how can we think those rays qualities also, unless one quality may
be the subject of and sustain another; which in effect is to call it a sub-
stance. We should not know bodies for substances, were it not for their
SEVENTEENTH CENTURY NATURAL SCIENCE 133
sensible qualities, and the principal of those being now found due to
something else, we have as good reason to believe that to be substance
also.
Besides, whoever thought any quality to be a heterogenous aggre-
gate, such as light is discovered to be. But to determine more abso-
lutely what light is, after what manner refracted, and by what modes
or actions it produces in our minds the phantasms of colours, is not so
easy. And I shall not mingle conjectures with certainties.
Reviewing what I have written, I see the discourse itself will lead
to divers experiments sufficient for its examination, and therefore I shall
not trouble you further, than to describe one of those which I have
already insinuated.
In a darkened room make a hole in the shut of a window, whose
diameter may conveniently be about a third part of an inch, to admit a
convenient quantity of the sun's light; and there place a clear and
colourless prism, to refract the entering light towards the further part
of the room, which, as I said, will thereby be diffused into an oblong
coloured image. Then place a lens of about three feet radius (suppose
a broad object glass of a three- foot telescope,) at the distance of about
four or five feet from thence, through which all those colours may at
once be transmitted, and made by its reflection to convene at a further
distance of about ten or twelve feet. If at that distance you intercept
this light with a sheet of white paper, you will see the colours converted
into whiteness again by being mingled. But it is requisite that the prism
and lens be placed steady, and that the paper on which the colours are
cast be moved to and fro ; for by such motion, you will not only find at
what distance the whiteness is most perfect, but also see how the colours
gradually convene, and vanish into whiteness, are again dissipated and
severed, and in an inverted order retain the same colours which they
had before they entered into the composition. You may also see, that if
any of the colours at the lens be intercepted, the whiteness will be
changed into the other colours. And therefore that the composition of
whiteness be perfect, care must be taken that none of the colours fall
beside the lens.
In the annexed design of this experiment, ABC expresses the prism
set endwise to sight, fig. 14, pi. 14, close by the hole F of the window
E.G. Its verticle angle ACB may conveniently be about 60 degrees:
MN designs the lens. Its breadth 2\ or 3 inches. SF one of the straight
lines, in which dirform rays may be conceived to flow successively from
134 SEVENTEENTH CENTURY NATURAL SCIENCE
the sun. FP and FR two of those rays unequally refracted, which the
lens makes to converge towards Q, and after decussation to diverge
again. And HI the paper, at divers distances, on which the colours are
projected; which in Q constitutes whiteness, but are red and yellow in
R, r, and 8, and blue and purple in P, p, and w.
If you proceed further to try the impossibility of changing any
uncompounded colour, (which I have asserted in the 3d and I3th prop-
ositions) it is requisite that the room be made very dark, least any
scattering light mixing with the colour disturb and alloy it, and render
it compound, contrary to the design of the experiment. It is also
requisite, that there be a perfecter separation of the colours than, after
the manner above described, can be made by the refraction of one single
prism, and how to make such further separations, will scarcely be dif-
ficult to them that consider the discovered laws of refractions. But if
trial shall be made with the colours not thoroughly separated, there
must be allowed changes proportionable to the mixture. Thus, if com-
pound light fall upon blue bise, the bise will not appear perfectly yellow,
but rather green, because there are in the yellow mixture many rays
indued with green, and green being less remote from the usual colour of
bise than yellow, is the more copiously reflected by it.
In like manner, if any one of the prismatic colours, suppose red,
be intercepted, on design to try the asserted impossibility of reproducing
that colour out of the others which are pretermitted ; it is necessary,
either that the colours be very well parted before the red be intercepted,
or that together with the red the neighbouring colours, into which the
red is secretly dispersed, (that is, the yellow, and perhaps green too)
be intercepted, or else, that allowance be made for the emerging of so
much red out of the yellow green, as may possibly have been diffused,
and scatteringly blended in those colours. And if these things be ob-
served, the new production of red or any intercepted colour will be
found impossible.
This I conceive is enough for an introduction to experiments of this
kind ; which if any of the Royal Society shall be so curious as to prose-
cute, I should be very glad to be informed with what success ; that, if
anything seem to be defective or to thwart this relation, I may have an
opportunity of giving further direction about it, or of acknowledging my
errors, if I have committed any.
SEVENTEENTH CENTURY NATURAL SCIENCE 135
THE THEORY OF GRAVITATION
PROPOSITION I. THEOREM I.
That the areas, ivhich bodies, when moving in curves, cut off by
radii drawn to a fixed center of force, are in one fixed plane and are
proportional to the times.
a
Let the time be divided into equal parts, and in the first period of
time let the body driven by one force describe the line AB. In the
second period, it would, if nothing hindered it, go on to c, describing the
line Be equal to AB. Then by the radii AS, BS, cS to the center S
would be cut off the equal areas ASB, BSc [the bases being equal and
the altitude the same]. Now when the body comes to B, a centripetal
force [in the direction BS] acts upon it with uniform impulse, and
makes it leave the line of direction Be and pass along the line BC. Let
cC be drawn parallel to the direction of the force BS, meeting BC in C.
Then at the end of the second (equal) period the body will be found at
C, in the same plane with the triangle ASB. Draw SC. Then the tri-
angle SBC, on account of the parallels SB and cC, will be equal to the
triangle SBc and therefore to the triangle SAB, etc. — Therefore in equal
times equal areas will be described in the same plane. — Let the number
of the triangles be increased and their altitude diminished to infinity:
their ultimate perimeter will be a curve (Cor. iv. Lem. iii.). And there-
fore a centripetal force, by which a body is continually drawn from a
course tangent to this curve, will act along this radius and whatever
areas have been described proportional to the times, will remain pro-
portional to the same times when curvilinear.
136 SEVENTEENTH CENTURY NATURAL SCIENCE
PROPOSITION II. THEOREM II.
Every body, which is moved in any curve described in a plane, and
cuts off, by radii drawn to a center that is stationary or moving in a
straight line with uniform motion, areas about the center proportional to
the times, is drawn by a centripetal force urging it toward the center.
For every body that is moved in a curved line, is turned from its
course by some force acting upon it. And that force by which a body is
turned from a straight line, and is made to describe the supposed equal
triangles SAB, SBC, etc., about the fixed center S in equal times must
act at the point B in a line parallel to Cc.
[For extend AB to c making AB=Bc. Then c is where the body
would have been had it not been drawn by the new force at B. Hence
at B the force acts in the direction Cc.]
But cC is parallel to BS. [For since the triangle SCB = triangle
SAB by hypothesis, and triangle SAB = SBc (equal altitude and bases)
then triangles SBC and SBc must be equal and Cc and SB must be
parallel, in order to have the altitude equal.] Therefore at B the force
acts along the line BS toward the center S. Therefore the force always
acts toward the immovable center S.
[It will be remembered that Kepler had already shown that the
planets move in ellipses, and do cut off areas proportioned to the times.
Hence they act as if drawn by a centripetal force. Then what is this
force? The next great step was to prove it identical with weight.]
PROPOSITION IV. THEOREM IV.
That the moon is drawn by gravity [weight} toward the earth, and
is deflected by the force of gravity from a straight line [tangent], and
thus held in her orbit.
The mean distance of the moon from the earth in terms of semi-
SEVENTEENTH CENTURY NATURAL SCIENCE 137
diameters of the earth is, according to Ptolemy and many astronomers,
59 ; according to Vendelius and Huyghens, 60 ; according to Copernicus,
60 1-5 ; according to Streetus, 60 2-5, and according to Tycho, 56 1-2.
( But Tycho has erred ) Let us assume that the mean distance is
60 semi-diameters of the earth. The moon completes her full periodic
times (goes round the earth) in 27 days, 7 hours, 43 minutes, as is deter-
mined by astronomers. The circumference of the earth is 123,249,600
Paris feet, as has been calculated by the French measurements. If the
moon should be deprived of every other motion, and drawn by that
one alone by which she is held in her orbit, she would fall to the earth.
The distance she would fall in the first minute would be 15 1-12 Paris
feet. This follows from calculation or from Proposition xxvi., Bk. I.,
or (what amounts to the same thing) from Cor. ix., Prop, iv., the same
Book. For the versed sine (distance along the radius from the chord
to the circumference) of that arc which the moon describes in one min-
ute at her mean motion and at a distance of 60 semi-diameters of the
earth from the earth is about 151-2 Paris feet, or, more accurately, 15
feet, I inch, and I 4-9 lines. [This is found as follows : The distance of
the moon from the earth is 60 radii of the earth. Hence the orbit of the
moon equals 60 times the circumference of the earth. Divide this result
by the number of minutes (39,343) in the moon's periodic time, and
the quotient is the arc passed over by the moon in one minute (about
187,964 Paris feet). In the diagram Mm is the arc passed over by
the moon in one minute, MX is the distance the moon has been deflected
from a tangent in one minute and the distance she would fall toward the
earth in this time if acted on by gravity alone. Arc Mm squared equals
MX times MA (diameter moon's orbit), or Mx = Mm2 divided by
MA, or 35,330,465,296 feet divided by 2,353,893,976 or 15 1-12 feet.]
Now since this force in approaching the earth increases in inverse
ratio with the square of the distance, therefore at the surface of the
earth it will be greater by 60x60 than at the moon [the distance being
60 radii of the earth] . Then a body driven by this force in falling in
our locality ought to pass over in the first minute 60x60x15 I~12 Paris
feet, and in the space of one second 15 1-12 Paris feet or, more accu-
rately 1 5 feet, i inch, and I 4-9 lines. But heavy bodies do actually fall
at this rate on the earth. For the length of a pendulum, oscillating each
second in the latitude of Lutetia, Paris, is three Paris feet and 81-2
lines, as Huyghens has observed, and the distance which a body falls in
a second when pulled by gravity is to the length of such a pendulum as
V 6—9
138 SEVENTEENTH CENTURY NATURAL SCIENCE
the square of the circumference of a circle to its diameter, as Huyghens
has also observed; and this is 15 Paris feet, I inch, I 7-9 lines. Hence
the force by which the moon is held in its orbit, if it were brought down
upon earth, would be equal to the force of gravity among us, and hence
is that very force which we are wont to call (weight or) gravity.
BOOK III. PROPOSITION V. THEOREM V. SCHOLIUM
The force which retains the celestial bodies in their orbits has
been hitherto called centripetal force; but it being now made plain
that it can be no other than a gravitating force, we shall hereafter call
it gravity. For the cause of that centripetal force which retains the
moon in its orbit will extend itself to all the planets.
BOOK III. PROPOSITION VI. THEOREM VI.
That all bodies gravitate towards every planet; and that the weights
of bodies towards any the same planet, at equal distances from the cen-
tre of the planet, are proportional to the quantities of matter which they
severally contain.
It has been, now of a long time, observed by others, that all sorts
of heavy bodies (allowance being made for the inequality of retardation
which they suffer from a small power of resistance in the air) descend to
the earth from equal heights in equal times ; and that equality of times
we may distinguish to a great accuracy, by the help of pendulums. I
tried the thing in gold, silver, lead, glass, sand, common salt, wood,
water, and wheat. I provided two wooden boxes, round and equal; I
filled the one with wood, and suspended an equal weight of gold (as
exactly as I could) in the centre of oscillation of the other. The boxes
hanging by equal threads of 1 1 feet made a couple of pendulums per-
fectly equal in weight and figure, and equally receiving the resistance of
the air. And, placing the one by the other, I observed them to play
together forwards and backwards, for a long time, with equal vibra-
tions. . . . and the like happened in the other bodies. By these ex-
periments, in bodies of the same weight, I could manifestly have dis-
covered a difference of matter less than the thousandth part of the
whole, had any such been. But, without all doubt, the nature of gravity
towards the planets is the same as towards the earth. . . . Moreover,
since the satellites of Jupiter perform their revolutions in times which
observe the sesquiplicate proportion of their distances from Jupiter's
centre — that is, equal at equal distances. And, therefore, these satel-
SEVENTEENTH CENTURY NATURAL SCIENCE 139
lites, if supposed to fall towards Jupiter from equal heights, would de-
scribe equal spaces in equal times, in like manner as heavy bodies do on
our earth. ... If, at equal distances from the sun, any satellite, in
proportion to the quantity of its matter, did gravitate towards the sun
with a force greater than Jupiter in proportion to his, according to any
given proportion, suppose of d to e; then the distance between the cen-
tres of the sun and of the satellite's orbit would be always greater than
the distance between the centres of the sun and of Jupiter nearly in the
sub-duplicate of that proportion ; as by some computations I have found.
And if the satellite did gravitate towards the sun with a force, lesser in
the proportion of e to d, the distance of the centre of the satellite's orbit
from the sun would be less than the distance of the centre of Jupiter
from the sun in the sub-duplicate of the same proportion. Therefore if,
at equal distances from the sun, the accelerative gravity of any satellite
towards the sun were greater or less than the accelerative gravity of
Jupiter towards the sun but one i-iooo part of the whole gravity, the
distance of the centre of the satellite's orbit from the sun would be
greater or less than the distance of Jupiter from the sun by one 1-2000
part of the whole distance — that is, by a fifth part of the distance of the
utmost satellite from the centre of Jupiter ; an eccentricity of the orbit
which would be very sensible. But the orbits of the satellite are con-
centric to Jupiter, and therefore the accelerative gravities of Jupiter,
and of all its satellites towards the sun, are equal among themselves . . .
But further; the weights of all the parts of every planet towards
any other planet are one to another as the matter in the several parts ;
for if some parts did gravitate more, others less, than for the quantity of
their matter, then the whole planet, according to the sort of parts with
which it most abounds, would gravitate more or less than in proportion
to the quantity of matter in the whole. Nor is it of any moment whether
these parts are external or internal; for if, for example, we should
imagine the terrestrial bodies with us to be raised up to the orb of the
moon, to be there compared with its body ; if the weights of such bodies-
were to the weights of the external parts of the moon as the quantities
of matter in the one and in the other respectively ; but to the weights of
the internal parts in a greater or less proportion, then likewise the
weights of those bodies would be to the weight of the whole moon in a
greater or less proportion ; against what we have showed above.
Cor. i. Hence the weights of bodies do not depend upon their
forms and textures ; for if the weights could be altered with the forms,
140 SEVENTEENTH CENTURY NATURAL SCIENCE
they would be greater or less, according to the variety of forms, in equal
matter ; altogether against experience.
Cor. 2. Universally, all bodies about the earth gravitate towards
the earth; and the weights of all, at equal distances from the earth's
centre, are as the quantities of matter which they severally contain.
This is the quality of all bodies within the reach of our experiments;
and therefore (by rule 3) to be affirmed of all bodies whatsoever. . . .
Cor. 5. The power of gravity is of a different nature from the
power of magnetism; for the magnetic attraction is not as the matter
attracted. Some bodies are attracted more by the magnet ; others less ;
most bodies not at all. The power of magnetism in one and the same
body may be increased and diminished ; and is sometimes far stronger,
for the quantity of matter, than the power of gravity ; and in receding
from the magnet decreases not in the duplicate but almost in the tripli-
cate proportion of the distance, as nearly as I could judge from some
rude observations.
BOOK III. PROPOSITION VII. THEOREM VII.
That there is a power of gravity tending to all bodies, proportional
to the several quantities of matter which they contain.
That all the planets mutually gravitate one towards another, we
have proved before ; as well as that the force of gravity towards every
one of them, considered apart, is reciprocally as the square of the dis-
tance of places from the centre of the planet. And thence (by prop. 69,
book I, and its corollaries) it follows, that the gravity tending towards
all the planets is proportional to the matter which they contain.
Moreover, since all the parts of any planet A gravitate towards any
other planet B ; and the gravity of every part is to the gravity of the
whole as the matter of the part to the matter of the whole ; and (by law
3) to every action corresponds an equal reaction ; therefore the planet B
will, on the other hand, gravitate towards all the parts of the planet A ;
and its gravity towards any one part will be to the gravity towards the
whole as the matter of the part to the matter of the whole. Q. E. D.
Cor. i. Therefore the force of gravity towards any whole planet
arises from, and is compounded of, the forces of gravity towards all its
parts. Magnetic and electric attractions afford us examples of this ; for
all attraction towards the whole arises from the attractions towards the
several parts. The thing may be easily understood in gravity, if we
consider a greater planet as formed of a number of lesser planets meet-
SEVENTEENTH CENTURY NATURAL SCIENCE 141
ing together in one globe ; for hence it would appear that the force of
the whole must arise from the forces of the component parts. If it is
objected that, according to this law, all bodies with us must mutually
gravitate one towards another, I answer, that since the gravitation
towards these bodies is to the gravitation towards the whole earth as
these bodies are to the whole earth, the gravitation towards them must
be far less than to fall under the observation of our senses.
Cor. 2. The force of gravity towards the several equal particles of
any body is reciprocally as the square of the distance of places from the
particles ; as appears from cor. 3, prop. 74, book I.
[Under Proposition X. is the following important passage:]
However the planets have been formed while they were yet in fluid
masses, all the heavier matter subsided to the centre. Since, therefore,
the common matter of our earth on the surface thereof is about twice
as heavy as water, and a little lower, in mines, is found about three, or
four, or even five times more heavy, it is probable that the quantity of
the whole matter of the earth may be five or six times greater than if it
consisted all of water. — Translated from the "Principia."
HUYGHENS
CHRISTIAN HUYGHENS was born at The Hague, April 14, 1629.
He studied law in Breda, but became interested in mathematics and neg-
lected his law for it. In 1655 he improved on the method of grinding
telescopic lenses, and with his brother Constantine discovered the sixth
satellite of Saturn and the fact that it was surrounded by rings.
In 1657 he presented the first pendulum-clock to the states-general.
The years 1665 to 1681 he spent in France at the "Library of the King."
During this time he determined the relation between the length and
time of oscillation of the pendulum, and solved the problem of the
center of oscillation. In 1678 he had thought out his wave theory of
light and in 1690 published it at Leyden.
He died at The Hague, June 8, 1695.
142 SEVENTEENTH CENTURY NATURAL SCIENCE
THE WAVE THEORY OF LIGHT
Proofs in optics, as in every science in which mathematics is applied
to matter, are founded upon facts from experience — as for example,
that light moves in straight lines, that the angles of incidence and re-
flection are equal, and that light rays are refracted in accordance with
the law of sines [i. e., that the ratio between the sines of the incident and
refracted ray is constant for the same substance.] For this last law is
now as generally and surely known as either of the others.
Most writers in optics have been content to assume these facts, but
others more curious have attempted to discover the source and reason
of these phenomena, looking upon them as being in themselves interest-
ing data. Yet although they have propounded some ingenious theories,
intelligent readers still require a fuller explanation before being entirely
satisfied. Therefore I herein offer some considerations on the matter
with the hope of making clearer this branch of physics which has not
improperly gained the reputation of being very obscure.
I feel myself particularly indebted to those that first began to study
these profound subjects, and to lead us to hope them capable of orderly
explanation. Yet I have been surprised to find these very investigators
accepting arguments far from clear as if proof conclusive. No one has
yet offered even a probable explanation of the first two remarkable
phenomena of light, — why it moves in straight lines, and why rays
from any and all directions can cross one another without interference.
I shall attempt in this treatise to submit clearer and more probable
reasons, along the lines of modern philosophy, first for the transmission
of light, and, second, for its reflection when it meets certain bodies.
Further, I shall explain the fact of rays said to undergo refraction
in passing through various transparent bodies. Here I shall consider
also, the refractions due to the differing densities of the atmosphere.
Later I shall investigate the remarkable refraction occurring in Icelandic
crystals. Finally, I shall study the different shapes necessary in trans-
parent and reflecting bodies in order to bring together rays upon a single
point or to deflect them in different ways. Here we shall see how easy
it is by our new theory to determine not alone the ellipses, hyperbolas,
and other curves which M. Descartes has so shrewdly constructed for
SEVENTEENTH CENTURY NATURAL SCIENCE 143
this end, but as well the curve that one surface of a lens must have when
the other surface is known, as spherical, plane, or any other figure.
We cannot but believe that light is the motion of a certain material.
Thus when we reflect on its production, we discover that here on the
earth it is usually emitted from fire and flame, and that these unques-
tionably contain bodies in rapid motion, since they can soften and melt
many other more solid substances. If we note its effects, we see that
when light is brought to a point, as, for example, by concave mirrors, it
can cause combustion the same as fire : that is, it can force bodies apart,
a power that certainly argues motion, at least in that true science where
one believes all natural phenomena to result from mechanical causes.
Moreover, in my mind we must either admit this or give up all hope of
ever understanding anything in natural science.
Since, according to this philosophy, it is believed certain that the
sensation of sight is produced only by the impulse of some form of mat-
ter against the nerves at the base of the eye, we have yet another reason
for believing light to be a motion in the substance lying between us and
the body producing the light.
As soon as we consider, moreover, the enormous speed with which
light travels in every direction, and the fact that when rays come from
different directions, even from those exactly opposite, they cross without
interference, it must be plain that we do not see luminous objects by
means of particles transmitted from the objects to us, as a shot or an
arrow moves through the air. For surely this would not allow for the
two qualities of light just mentioned, particularly the latter (that of
speed). Light, then, is transmitted in some other way, a comprehen-
sion of which we may get from our knowledge of how sound moves
through the air.
We know that sound is sent out in all directions through the medi-
um of the air, a substance invisible and impalpable, by means of a motion
that is communicated successively from one part of the air to the next ;
and as this movement has the same speed in all directions, it must form
spherical surfaces that keep enlarging until at last they strike the ear.
Now there can be no doubt that light likewise reaches us from a lumin-
ous substance through some motion caused in the matter lying in the
intervening space, — for we have seen above that this cannot take place
through the transmission of matter from one place to another.
If, moreover, light requires time for its passage — a matter we shall
discuss in a moment — it will then follow that this movement is caused
144
SEVENTEENTH CENTURY NATURAL SCIENCE
in the substance gradually, and therefore is transmitted, like sound, by
surfaces and spherical waves. I call these waves because of their like-
ness to those formed when one throws a pebble into water, which are
examples of gradual propagation in circles, although from a different
cause and on a plane surface.
In regard to the question of light requiring time for its transmis-
sion, let us consider whether there is any experimental evidence
against it.
What experiments we can make here on the earth with sources of
light placed at great distances (although indicating that it does not
take a sensible time for light to pass over these distances) are subject
to the objection that these distances are yet too small, and that we can
only argue that the movement of light is enormously fast. M. Descartes
)hought it to be instantaneous and based his opinion upon much better
reasons taken from the eclipse of the moon. Yet as I shall make clear,
even this evidence is not decisive. I shall state the matter in a some-
what different way from his in order to more easily exhibit all the con-
sequences.
Suppose S to be the position of the sun, E A part of the orbit of the
earth, S E M a straight line intersecting in M, the orbit of the moon,
represented by the circle A M.
Now if light requires time — say an hour — to move the distance be-
tween the earth and the moon, then [at the time of an eclipse] it follows
that when the earth has come to E its shadow, or the stoppage of the
light of the sun, will not yet have reached M [the moon] , and will not
for an hour. Counting from the instant the earth reaches E, it will be an
hour before will reach M if it is to be obscured there. This eclipse will
not be seen from the earth for yet another hour. Suppose that during
these two hours the earth has moved to X, the moon appearing eclipsed
at M, the sun still being seen at S. For I assume as does Copernicus
SEVENTEENTH CENTURY NATURAL SCIENCE 145
that the sun is fixed and since light moves in straight lines, is always
seen in its true position.
But as a matter of fact, we are assured that the eclipsed moon
always appears directly opposite the sun ; while on the above supposition
[that light takes an hour in passing between the moon and the earth],
its position ought to be back of the straight line by the angle Y X M,
the supplement of the angle S X M. But this is not the case, for this
angle Y X M would be very easily noticed, it being about 33 degrees.
For by our analysis (found in the essay on the causes of the phenom-
ena of Saturn), the distance from the sun to the earth, S E, is about
12,000 times the diameter of the earth, and hence 400 times the dis-
tance of the moon, which is 30 diameters. The angle X M E then will be
nearly 400 times as great as E S X, which is 5 minutes, i. e., the angular
distance travelled by the earth in two hours [the earth traversing almost
a degree in a day]. Thus the angle E M X is almost 33 degrees, and
likewise the angle M X Y, being 5 minutes greater [than E M X].
Now it must be remembered that in this computation it is assumed
that the speed of light is such as to consume an hour in passing from
here to the moon. But if we assume it to take only a minute of time,
then the angle Y X M would amount to only 33 minutes, and if it only
takes ten seconds, this angle will be less than six minutes. Now so small
an angle is not observable in a lunar eclipse and hence it is not permis-
sible to argue that light is absolutely instantaneous.
It is rather unusual, we admit, to take for granted a speed 100,000
times as great as that of sound, which (following my experiments)
travels about 180 toises [about 1150 feet] in a second, or during a pulse-
beat. Yet this supposition is not at all impossible, for it is not neces-
sary to carry a body at such speed but only for motion to traverse
successively from one point to another.
Hence I do not hesitate in this matter to assume that the passage of
light takes time, for on this assumption all phenomena can be explained,
while on the contrary supposition none of them can be explained.
In fact, it seems to me and to many others as well, that M. Descartes,
whose purpose has been to discuss all physical matters clearly, and who
has certainly succeeded in this better than any one before him, has writ-
ten nothing on light and its qualities that is not either hard to understand
or even incomprehensible.
Moreover, this idea that I have propounded as an hypothesis has
lately been made a well nigh established fact by that keen calculation of
146 SEVENTEENTH CENTURY NATURAL SCIENCE
Roemer, whose method I will here take occasion to describe, on the ex-
pectation that he will himself in the future fully confirm this theory.
His method, the same as the one we have just discussed, is astro-
nomical. He shows not only that light takes time for its passage, but
calculates also its speed and that this must be at least six times as much
as the rate I have just given as an estimate.
In his demonstration he uses the eclipses of the small satellites that
revolve around Jupiter, and very frequently pass into his shadow. Roe-
mer's reasoning is this :
Let S be the sun, B C D E the yearly orbit of the earth, J Jupiter
and G H the orbit of his nearest satellite, for this one because of its
short period is better suited to this investigation than any one of the
other three. Suppose G to be the point where the satellite enters, and
H where it leaves, Jupiter's shadow.
Suppose that when the earth is at B, the satellite is seen to emerge
[at G], at some time before the last quarter. Were the earth to remain
stationary there, 42^ hours would elapse before the next emergence
would take place, for this much time is taken by the satellite in making
one revolution in its orbit and returning to opposition to the sun. For
example, if the earth remained at B during 30 revolutions, then after
30 times 42^ hours, the satellite would again be seen to emerge. If in
the meantime the earth has moved to C, farther from Jupiter, it is clear
that if light requires time for its passage, the emergence of the satellite
will be seen later when the earth is at C than when at B. For we must
add to the 30 times 42^ hours, the time occupied by light in passing
over the difference between the distances [of the earth from Jupiter]
G B and G C, i. e., M C. So in the other quarter, when the earth
travels from D to E, approaching Jupiter, the eclipses will occur earlier
when the earth is at E than when at D.
SEVENTEENTH CENTURY NATURAL SCIENCE 147
Now by many observations of these eclipses throughout ten years,
it is shown that these inequalities are actually of some moment, amount-
ing to as much as ten minutes or more: whence it is argued that in
traversing the whole diameter of the earth's orbit, K L, double the dis-
tance from the earth to the sun, light takes about 22 minutes.
The motion of Jupiter in its orbit while the earth passes from B to
'C or from D to E has been taken into consideration in Roemer's cal-
culation, where it is also proved that these inequalities cannot be caused
by any irregularity or eccentricity in the movement of the satellite.
Now if we consider the enormous size of this diameter K L [the
•earth's orbit] which I have estimated to be about 24,000 times that of
the earth, we get some comprehension of the extraordinary speed of
light.
Even if K L were only 22,000 diameters of the earth, a speed tra-
versing this distance in 22 minutes would be equal to the rate of a
thousand diameters a minute, i. e., 16 2-3 diameters a second (or a
pulse-beat) which makes more than 1,100 times 100,000 toises, since one
diameter of the earth equals 2,865 leagues, of which there are 25 to the
degree, and since in accordance with the very precise calculation made
by Mr. Picard in 1669 under orders from the king, each league contains
2,282 toises.
As I stated before sound moves only 180 toises per second. Hence
the speed of light is over 600,000 times as great as that of sound, which,
however, is very different from being instantaneous, — it is the difference
between any finite number and infinity. The theory that light move-
ments are propagated from point to point in time being thus demon-
strated, it follows that light moves in spherical waves, as does sound.
But if they are alike in this regard, they are unlike in others, as in
the original cause of the motion that transmits them, the medium
through which they move, and the manner in which they are transmitted
in it.
We know that sound is caused by the rapid vibration of some body
(either as a whole or in part), this vibration setting in motion the ad-
joining air. But light movements must arise at every point of the
luminous body, otherwise all the various parts of the body would not
be visible. This fact will be clearer from what follows.
In my judgment, this movement of light-giving bodies cannot be
more satisfactorily explained than by supposing that those that are fluid,
e. g., a flame, and probably the sun and stars, consist of particles that
148 SEVENTEENTH CENTURY NATURAL SCIENCE
float about in a much rarer medium, that sets them in violent motion,
causing them to strike against the still more minute particles of the
surrounding ether. In the case of light-giving solids such as red-hot
metal or carbon we may suppose this movement to be caused by the
rapid motions of the metal or wood, the particles on the surface excit-
ing the ether. Hence the vibration producing light must be much
shorter and faster than that causing sound, since we do not find that
sound disturbances give rise to light any more than the wave of the
hand through the air causes sound.
The next question is in regard to the nature of the medium through
which the vibration produced by light-giving bodies moves. I have
named it ether, but it plainly differs from the medium through which
sound moves. The latter is simply the air we feel and breathe, and when
it is removed from any space, the medium which carries light
still remains. This is shown by surrounding the sounding body in a
glass vessel, and exhausting the air by means of the air-pump that Mr.
Boyle has devised, and with which he has performed so many striking
experiments. In trying this experiment, however, it is best to set the
sounder on cotton or feathers so that it cannot communicate vibrations
to the glass receiver or the air-pump, a point hitherto neglected. Then,
when all the air has been exhausted, one catches no sound from the
metal when it is struck.
Hence we conclude not only that our atmosphere which cannot pen-
etrate glass is the medium through which sound acts, but that the me-
dium carrying light- vibrations is something different : for after the ves-
sel is exhausted of air, light passes through it as easily as before.
The last point is proven even more conclusively by the famous ex-
periment of Torricelli. [Fill a long closed glass tube with mercury,
then invert it.] The top of the glass tube not filled by the mercury con-
tains a high vacuum, but transmits light as well as when filled with air.
This demonstrates that there is within the tube some form of matter dif-
ferent from air, and which penetrates either glass or mercury, or both,
though both are impenetrable to air. And if a like experiment is tried
with a little water on top of the mercury, it becomes equally clear that
the substance in question traverses either glass or water or both.
In regard to the different methods of transmission of sound and
light, in the case of sound it is easy to see what happens when one re-
members that air can be compressed and reduced to a much smaller vol-
ume than usual, and that it tends with the same force to expand to its
SEVENTEENTH CENTURY NATURAL SCIENCE H9
original volume. This quality, considered along with its penetrability
retained in spite of such condensation seems to show that it consists of
small particles that float about in rapid vibration in an ether consisting
of still more minute particles. Sound, then, is caused by the struggle
of these particles to escape when at any point in the course of a wave
they are more crowded together than at some other point.
Now the wonderful speed of light considered with its other quali-
ties, does not permit us to believe it to be transmitted in the same man-
ner. Therefore I shall try to explain the way in which I think it must
take place. I must first, however, describe that quality of hard sub-
stances through which they transmit motion one to another. If one
take a number of balls of the same size of any hard substance, and place
them touching one another in one line, he will find that on letting a
ball of the same size strike against one end of the line, the motion is
transmitted in an instant to the other end of the line. The last ball is
driven from the line while the others are apparently undisturbed, the
ball that struck the line coming to a dead stop. This is an illustration
of a transmission of motion at great speed, varying directly as the hard-
ness of the balls. Yet it is certain that this transmission is not instan-
taneous, but requires time. For if the movement, or if you wish, the
tendency to move, did not pass from one ball to another in succession,
they would all be set in motion at the same instant and would all move
forward at the same time. Now this is so far from the case that only
the last one leaves the row, and it has the speed of the ball that first
struck the line.
There are other experiments, also demonstrating that all bodies,
even those thought hardest, such as steel, glass and agate, are really elas-
tic, and bend a little, no matter whether they are in rods, balls, or bodies
of any other shape, — that is, they give slightly at the point where struck,
and at once regain their former shape. Thus I have discovered that in
letting a glass or agate ball strike on a large, thick, flat piece of the same
substance the surface of which has been roughened by the breath, the
place where it strikes is shown by a circular indentation that varies in
size directly as the force of the blow. This indicates that the materials
give when struck and then fly back, — an event that necessarily takes
time.
Now to apply such a motion to the explanation of light, there is
nothing in the way of our imagining the particles of ether to have an
almost complete hardness, and an elasticity as perfect as we need wish.
150 SEVENTEENTH CENTURY NATURAL SCIENCE
We need not here discuss the cause of either this hardness of elasticity,
as this would lead us too far from the question at issue. I will remark^
however, by the way, that these particles of ether, in spite of their mi-
nuteness, are also composed of parts and that their elasticity depends on
a very rapid motion of a subtle substance traversing them in all direc-
tions and making them take a structure that offers a ready passage to
this fluid. This agrees with the idea of M. Descartes, except that I
would not, like him, give the pores the shape of round, hollow canals.
This is so far from being at all absurd or incomprehensible that it is,
easily credible that nature uses an infinite series of different-sized mole-,
cules in order to produce her marvelous effects.
Moreover, although we do not know the cause of elasticity, we.
cannot have failed to notice that most bodies possess this characteristic;
hence it is not unreasonable to suppose that it is a quality of the minute,
invisible particles of the ether. And it is a fact that if one looks for
some other method of accounting for the gradual transmission of light,
he will have a hard time finding any supposition better suited than elas-
ticity to explain the fact of uniform speed. This [uniform speed] seems,
to be a necessary assumption, for if the motion slowed down when dis-
tributed over a great mass of matter at a far distance from its source,
then this great speed would at last be lost. On the other hand, we sup-
pose ether to have the property of elasticity so that its particles regain
their shape with equal activity whether struck a hard or gentle blow..
Thus the rate at which light would move would remain constant.
TRANSLATED FROM TRAITE' DE LA LUMIERE.
THE BEGINNING OF CHEMISTRY
As ASTROLOGY was the forerunner of astronomy, so the herald of
chemistry was alchemy. In ancient times alchemy went hand in hand
with astrology in studying the hidden influences had by the spirits of
the heavens and earth over mortals.
Alchemists believed all things to live, and the gases they had learned
to drive out of such compounds as red oxide of mercury to be the
spirits — the living souls — of these substances. They had not learned to
SEVENTEENTH CENTURY NATURAL SCIENCE 151
put the wide gulf which we do between life and matter, the spiritual
and the material, the supernatural and the natural, but thought all
things living, spiritual, and natural. "Everything, even heaven and hell,
are of this earth," says the pseudo-Plato. Hence alchemy puzzled itself
over the transmutation of metals, the philosopher's stone, the influence
of the spirits of things over health, the elixir of life and the like. Yet
most of the best known doctors of the Middle Ages, such as Geber, Avi-
cenna, Aviceborn and Roger Bacon, were alchemists, and the first great
represenative of medicine in modern times, Paracelsus, was another.
It was Paracelsus (1493-1541) who gave alchemy its most useful
bent, — "the true use of chemie," says he, "is not to make gold, but med-
icines."
The Arabians had discovered some of the acids. Paracelsus found
the medicinal use of antimony. Glauber ( 1604-1668) first made arti-
ficially sulphate of sodium, called Glauber's salt, and describes other
sulphates and chlorides. He thought mercury and salt to be the princi-
ples of all things.
Robert Boyle (1627-1691) examined the influence of pressure on
air and developed his law that (the temperature remaining the same)
the volume of air (or gas) varies inversely as the pressure. By this
time the idea that the gases in things are living souls was pretty well
overthrown.
Stahl (1660-1734) advanced the idea that all combustion is the
driving off of a fire-element, phlogiston. This theory accounted for
many facts and was not refuted for a century. He admitted water, acid,
earth and phlogiston as elements.
Robert Hooke in 1665 had set forward the opinion that air con-
tains a substance such as in saltpetre. Mayow (1645-1679), as stated
elsewhere, experimented on common air, and separated the "breathing
or fire-air" from the rest.
Joseph Black in the latter part of the eighteenth century showed
that magnesia and lime weigh less after being heated than before, and
that this is because of the expulsion from them of a "fixed air" (carbon
dioxide). He found, too, that they would absorb a large amount of
heat which became insensible to the touch. This heat he called "latent."
His experiments bring us directly to the work of Priestley, Caven-
dish and Lavoisier, and the beginning of scientific chemistry.
152 SEVENTEENTH CENTURY NATURAL SCIENCE
BOYLE
ROBERT BOYLE was the fourteenth child of the Earl of Cork and
was born in Munster, Ireland, January 25, 1627. His education was re-
ceived at Eton, at Stallbridge under the rector, and under private
tutors while travelling. His father died in 1644 and left him the Irish
estates. In 1645 ne became one of a group of scientists which after-
wards (1663) developed into the Royal Society. The rest of his life
was spent mostly in scientific research. He made many experiments
with the air-pump invented by Guericke on the relation of air to life.
Most of his work was in breaking ground in the newer fields of physics
and chemistry. Probably the most definite result reached by him was
his Law of Compressibility of Gases that the expansion of a gas is
practically in inverse ratio to the pressure upon it.
He died December 30, 1691.
THE DISCOVERY OF His LAW
"We took a long glass tube, which, by a dexterous hand and the help
of a lamp, was in such a manner crooked at the bottom, that the part
turned up was almost parallel to the rest of the tube, and the orifice
of this shorter leg of the syphon (if I may so call the whole instrument)
being hermetically sealed, the length of it was divided into inches (each
of which was subdivided into eight parts) by a straight list of paper,
which, containing those divisions, was carefully pasted all along it.
Then putting in as much quicksilver as served to fill the arch or bended
part of the syphon, that the mercury standing in a level might reach in
one leg to the bottom of the divided paper, and just to the same height
or horizontal line in the other, we took care, by frequently inclining the
tube, so that the air might freely pass from one leg into the other by
the sides of the mercury (we took, I say, care), that the air at last
included in the shorter cylinder should be of the same laxity with the
rest of the air about it. This done, we began to pour quicksilver into
the longer leg of the syphon, which, by its weight pressing up that in
the shorter leg, did by degrees straighten the included air ; and continu-
ing this pouring in of quicksilver till the air in the shorter leg was by
SEVENTEENTH CENTURY NATURAL SCIENCE 153
condensation reduced to take up but half the space it possessed (I say
possessed, not filled) before, we cast our eyes upon the longer leg of
the glass, upon which we likewise pasted a slip of paper carefully di-
vided into inches and parts, and we observed, not without delight and
satisfaction, that the quicksilver in that longer part of the tube was 29
inches higher than the other. Now that this observation does both very
well agree with and confirm our hypothesis, will be easily discerned by
him that takes notice what we teach: and Monsieur Pascal and our
English friend's [Mr. Townley's] experiments prove, that the greater
the weight is that leans upon the air, the more forcible is its endeavor
of dilation, and consequently its power of resistance (as other springs
are stronger when bent by greater weights) . For this being considered,
it will appear to agree rarely well with the hypothesis, that as according
to it the air in that degree of density, and correspondent measure of re-
sistance, to which the weight of the incumbent atmosphere had brought
it, was unable to counterbalance and resist the pressure of a mercurial
cylinder of about 29 inches, as we are taught by the Torricellian experi-
ment ; so here the same air being brought to a degree of density about
twice as great as that it had before, obtains a spring twice as strong
as formerly. As may appear by its being able to sustain or resist a
cylinder of 29 inches in the longer tube, together with the weight of the
atmospherical cylinder that leaned upon those 29 inches of mercury;
and, as we just now inferred from the Torricellian experiment, was
equivalent to them."
At this stage of the experiments the tube broke, and it was only
after several mischances that Boyle was able to complete his observa-
tions.
He then proceeded to the converse experiment — that is, to deter-
mine the spring of rarefied air. A tube, about 6 feet in length, and sealed
at one end, was nearly filled with mercury, and into it was placed "a
slender glass pipe of about the bigness of a swan's quill, and open at
both ends ; all along of which was pasted a narrow list of paper, divided
into inches and half-quarters. This slender pipe being thrust down into
the greater tube almost filled with quicksilver, the glass helped to make
it swell to the top of the tube; and the quicksilver getting in at the
lower orifice of the pipe filled it up till the mercury included in that
was near about a level with the surface of the surrounding mercury in
the tube. There being, as near as we could guess, little more than an inch
of the slender pipe left above the surface of the restagnant mercury,
V 6—10
154 SEVENTEENTH CENTURY NATURAL SCIENCE
and consequently unfilled therewith, the prominent orifice was carefully
closed with sealing-wax melted ; after which the pipe was let alone for
a while that the air, dilated a little by the heat of the wax, might, upon
refrigeration, be reduced to its wonted density. And then we observed,
by the help of the above-mentioned list of paper, whether we had not
included somewhat more or somewhat less than an inch of air ; and in
either case we were fain to rectify the error by a small hole made (with
a heated pin) in the wax, and afterward closed up again. Having thus
included a just inch of air, we lifted up the slender pipe by degrees, till
the air was dilated to an inch, an inch and a half, two inches, etc., and
observed in inches and eighths the length of the mercurial cylinder,
which, at each degree of the air's expansion, was impelled above the
surface of the restagnant mercury in the tube. The observations being
ended, we presently made the Torricellian experiment with the above
mentioned great tube of 6 feet long, that we might know the height of
the mercurial cylinder for that particular day and hour, which height
we found to be 29! inches."
Such were the experiments, simple and easily made, which led
Boyle to the recognition of the great law which bears his name — a law
which is so far from being "unuseful" that it is recognized by the phy-
sicist as of the first importance. And yet in spite of the thoroughness
with which Boyle did the work, and in spite, too, of the precision with
which he stated his results, the attempt has not been wanting to deprive
him of the whole merit of this discovery, and there is scarcely a text-
book of physics or chemistry on the Continent, or at least in France, in
which his name is mentioned in connection with the matter: abroad
they prefer to ascribe the glory to the Abbe Mariotte, although Mari-
otte's treatise, De la Nature de I' Air, in which he enunciates the law,
was not printed until seventeen years after Boyle had published his reply
to Linus. — Thorpe, Essays on Historical Chemistry.
SEVENTEENTH CENTURY POLi I
ECONOMY
TK3MOCHJI l^AJ 3HT
increase m un
be reco^nizeci to li;»
?n !!:>•• dark <-'sj.es. '.
larul. An;..-.-:
favor of the -
protection. Ivf<>n '
French of the restrkn-»- • Jr:
all industries in the hnrrc sraic \iun (1571-
1641 ) was the greatest F.ngli.«*i •• He maintained
that the great object of govervr.*-'" >•
THE LAST JUDGMENT
By Michael Angeto, 1475-1564.. in the listing Chapel, Rome
165
SEVENTEENTH CENTURY POLITICAL
ECONOMY
UNTIL the last century political economy — the science of wealth —
was discussed hand in hand with political science — the science of gov-
ernment— but for convenience we note elsewhere the growth of govern-
mental ideas. Political economy proper had little consideration in
ancient times. The economic decay of the Roman state gave rise to argu-
ments against slave labor and interest on loans, and to measures for the
increase of the free population, but economics as a science can hardly
be recognized to have existed. All large economic activity ceased dur-
ing the dark ages, but the subsequent growth of the cities and their trade
gave rise to what Adam Smith calls the mercantile theory of economics.
Jean Bodin in the latter half of the sixteenth century made a great
step in economic science by explaining the ten-fold rise in prices to the
importation of gold from the New World. He distinguished money
from wealth, but otherwise was a mercantilist in approving the inter-
ference of government in trade, high taxes on manufactured imports,
and low taxes on imported raw materials and food. In 1581 W. S.
(William Stafford) defended the exclusion of all foreign wares in Eng-
land. Antonio Serra, an Italian, writing in 1613 in prison, argued in
favor of the superior profit to the nation of manufactures and for their
protection. Monchretien de Watteville in 1615 gave an exposition in
French of the restrictive ideas. He believed in government control of
all industries in the home state and in colonies. Thomas Mun (1571-
1641 ) was the greatest English advocate of this system. He maintained
that the great object of governmental economics should be to main-
156 SEVENTEENTH CENTURY POLITICAL ECONOMY
tain the balance of trade, that is, the excess of exports over imports, and
that trade restrictions and tariffs should be formulated with this end in
view. Josiah Child in 1668 and 1690 favored a low rate of interest
maintained by government authority and exclusive control of the colo-
nial trade. He believed, like the rest of the mercantilists, in a large
and growing population. This, it will be remembered, was in direct
opposition to the old Greek idea.
The mercantile theory had been put into practical use by most
nations, and everywhere there were fast-bound restrictions on industry.
This at length caused a reaction that later led, in what are called the
physiocrats, to the opposite extreme.
Sir William Petty (1623-1687) was a precursor of the new school.
He founded the value of an article on the labor required to produce it,
argued for a single money standard, against a fixed rate of interest, and
in general did not believe in government control. Sir Dudley North
(1691) was also an opponent of the restrictive theory. He believed in
home as well as foreign trade, and in non-interference by the govern-
ment. John Locke based all property on labor — a theory that implied
great political consequences.
These reactionary ideas took root in France and developed rapidly.
Pierre Boisguillebert in the first of the eighteenth century, vainly strug-
gled against government restrictions for the sake of manufactures,
and lauded agriculture. Restrictions between nations he thought as
harmful as between individuals. He brought forward the idea of a tax
on incomes. But his words fell on deaf ears and had little influence.
Vaubon in 1707 took up the same line of thought and urged more con-
sideration for the laboring and agricultural class.
The great names, however, of the physiocrat school proper belong
to the eighteenth century, and were Quesnay (1684-1774) and Gournay
(1712-1759). They took for granted the doctrine of the natural rights
and equality of man, of the social contract as the basis of the state.
They thought that labor is the basis of property, but the soil the source
of all wealth. They argued that agriculture, mining, fishing, etc., are
the only truly productive occupations ; that manuf acturies and commerce
increase values only by the amount of labor put in them, and that this
labor is not really productive because the sum of raw materials is not
increased. "Laissez faire," non-intervention, should be the policy of
governments. Turgot tried to carry out their ideas in France, but he
SEVENTEENTH CENTURY POLITICAL, ECONOMY 157
was unsustained by Louis XVI., and the government plunged on blindly
to the Revolution.
In England David Hume brought his keen insight to bear against
the balance of trade theory, and the identification of money and wealth.
He was a friend of and unquestionably influenced, Adam Smith, but
Smith's Wealth of Nations is beyond doubt the beginning of modern
political economy.
THOMAS MUN
THOMAS MUN was born in London 1571. His father and uncle
were both connected with the mint. Mun was early a successful mer-
chant engaged mostly in Turkish trade. In July, 1615, he was elected
a director of the East India Company. His first book was a defence
of the transactions of that company. His second book, "England's
Treasure by Forraign Trade, or the Ballance of our Forraign Trade
is the Rule of our Treasure," was probably written about 1630, but not
published until 1664, twenty-three years after his death. The book
gives the best early expression to the views of the prevailing political
economy of the time. It is important, as the influence of the protective
theory which it represents has been enormous.
MUN'S "MERCANTILE THEORY"
THE MEANS TO ENRICH THE KINGDOM, AND TO ENCREASE OUR TREASURE
Although a Kingdom may be enriched by gifts received, or by
purchase taken from some other nations, yet these are things un-
certain and of small consideration when they happen. The ordinary
means therefore to encrease our wealth and treasure is by For-
raign Trade, wherein wee must ever observe this rule : to sell more to
strangers yearly than wee consume of theirs in value. For suppose that
when this Kingdom is plentifully served with the Cloth, Lead, Tinn,
Iron, Fish, and other native commodities, we doe yearly export the over-
plus to forraign Countries to the value of twenty two hundred thousand
158 SEVENTEENTH CENTURY POLITICAL, ECONOMY
pounds; by which means we are enabled beyond the Seas to buy and
bring in forraign wares for our use and consumptions, to the value of
twenty hundred thousand pounds. By this order duly kept in our trad-
ing, we may rest assured that the Kingdom shall be enriched yearly
two hundred thousand pounds, which must be brought to us in so much
Treasure; because that part of our stock which is not returned to us
in wares must necessarily be brought home in treasure.
For in this case it cometh to pass in the stock of a Kingdom, as
in the estate of a private man ; who is supposed to have one thousand
pounds yearly revenue and two thousand pounds of ready money in his
Chest: If such a man through excess shall spend one thousand five
hundred pounds per annum, all his ready money will be doubled if he
takes a Frugal course to spend but five hundred pounds per annum;
which rule never faileth likewise in the Commonwealth, but in some
cases (of no great moment) which I will hereafter declare, when I shall
shew by whom and in what manner this ballance of the Kingdom's ac-
count ought to be drawn up yearly, or so often as it shall please the
State to discover how much we gain or lose by trade with forraign
Nations. But first I will say something concerning those ways and
means which will encrease our exportations and diminish our importa-
tions of wares ; which being done, I will then set down some other argu-
ments both affirmative and negative to strengthen that which is here
declared, and thereby to shew that all the other means which are com-
monly supposed to enrich the Kingdom with Treasure are altogether
insufficient and meer fallacies.
The particular ways and means to encrease the exportation of our
Commodities, and to decrease our Consumption of forraign wares.
The revenue or stock of a Kingdom by which it is provided of for-
raign wares is either Natural or Artificial. The Natural wealth is so
much only as can be spared from our own use and necessities to be
exported unto strangers. The Artificial consists in our manufactures
and industries trading with forraign commodities, concerning which
I will set down such particulars as may serve for the cause we have in
hand.
I. First, although this Realm be already exceeding rich by nature,
yet might it be much encreased by laying the waste grounds (which are
infinite) into such employments as should no way hinder the present
revenues of other manured lands, but hereby to supply our selves and
SEVENTEENTH CENTURY POLITICAL ECONOMY 159
prevent the importations of Hemp, Flax, Cordage, Tobacco, and divers
other things which now we fetch from strangers to our great impover-
ishing.
2. We may likewise diminish our importations if we would soberly
refrain from excessive consumption of forraign wares in our diet and
rayment, with such often change of fashions as is used, so much the
more to encrease the waste and charge ; which vices at this present are
more notorious amongst us than in former ages. Yet might they easily
be amended by enforcing the observation of such good laws as are
strictly practised in other Countries against the said excesses; where
likewise by commanding their own manufactures to be used, they pre-
vent the coming in of others, without prohibition, or offence to strangers
in their mutual commerce.
3. In our exportations we must not only regard our own super-
fluities, but also we must consider our neighbours' necessities, that so
upon the wares which they cannot want, nor yet be furnished thereof
elsewhere, we may (besides the vent of the Materials) gain so much of
manufacture as we can, and also endeavor to sell them dear, so far forth
as the high price cause not a less vent in the quantity. But the super-
fluity of our commodities which strangers use, and may also have the
same from other Nations, or may abate their vent by the use of some
like wares from other places, and with little inconvenience ; we must in
this case strive to sell as cheap as possible we can, rather than to lose
the utterance of such wares. For we have found of late years by good
experience, that being able to sell our Cloth cheaply in Turkey, we have
greatly encreased the vent thereof, and the Venetians have lost as much
in the utterance of theirs in those Countreys, because it is dearer. And
on the other side a few years past, when by the excessive price of Wools
our Cloth was exceeding dear, we lost at the least half our clothing for
forraign parts, which since is no otherwise (well neer) recovered again
than by the great fall of price for Wools and Cloth. We find that twenty
five in the Hundred less in the price of these and some other Wares,
to the loss of private mens revenues, may raise about fifty upon the
hundred in the quantity vented to the benefit of the publique.
For when Cloth is dear, other Nations doe presently practise cloth-
ing, and we know they want neither art nor materials to this perform-
ance. But when by cheapness we drive them from this employment,
and so in time obtain our dear price again, then do they also use their
former remedy. So that by these alterations we learn, that it is in
160 SEVENTEENTH CENTURY POLITICAL ECONOMY
vain to expect a greater revenue of our wares than their condition will
afford, but rather it concerns us to apply our endeavours to the times
with care and diligence to help our selves the best we may, by making
our cloth and other manufactures without deceit, which will encrease
their estimation and use.
4. The value of our exportations likewise may be much advanced
when we perform it ourselves in our own ships, for then we get only not
the price of our wares as they are worth here, but also the Merchants
gains, the charges of ensurance, and fraight to carry them beyond the
Seas. As for example, if the Italian Merchants should come hither in
their own shipping to fetch our Corn, our red Herrings or the like,
in this case the Kingdom should have ordinarily but 25.3 for a quarter
of Wheat, and 2O.s. for a barrel of red herrings, whereas if we carry
these wares ourselves into Italy upon the same rates, it is likely that we
shall obtain fifty shillings for the first, and forty for the last, which is
a great difference in the utterance or vent of the Kingdom's stock. And
although it is true that the commerce ought to be free to strangers to
bring in and carry out at their pleasure, yet nevertheless in many places
the exportation of victuals and munition are either prohibited, or at least
limited to be done onely by the people and Shipping of those places
where they abound,
5. The frugal expending likewise of our own natural wealth might
advance much yearly to be exported unto strangers ; and if in our ray-
ment we will be prodigal, yet let this be done with our own materials
and manufactures, as Cloth, Lace, Imbroderies, Cutworks and the like,
where the excess of the rich may be the employment of the poor, whose
labours notwithstanding of this kind,would be more profitable for the
Commonwealth, if they were done to the use of strangers.
6. The Fishing in his Majesties seas of England, Scotland and
Ireland is our natural wealth, and would cost nothing but labour, which
the Dutch bestow willingly, and thereby draw yearly a very great profit
to themselves by serving many places of Christendom with our Fish, for
which they return and supply their wants both of forraign Wares and
Mony, besides the multitudes of Mariners and Shipping, which hereby
are maintain'd, whereof a long discourse might be made to shew the
particular manage of this important business. Our Fishing plantation
likewise in New-England, Virginia, Greenland, the Summer Islands,
and the New-Found-land, are of the like nature, affording much wealth
SEVENTEENTH CENTURY POLITICAL ECONOMY 161
and employments to maintain a great number of poor, and to encrease
our decaying trade.
7. A staple or Magazin for forraign Corn, Indico, Spices, Raw-
silks, Cotton, wool or any other commodity whatsoever, to be imported
will encrease Shipping, Trade, Treasure, and the Kings customes, by
exporting them again where need shall require, which course of trading,
hath been the chief means to raise Venice, Genoa, the low-Countreys,
with some others; and for such a purpose England stands most com-
modiously, wanting nothing to this performance but our own diligence
and endeavour.
8. Also wee ought to esteem and cherish those trades which we
have in remote or far Countreys, for besides the encrease of Shipping
and Mariners thereby, the wares also sent thither and received from
thence are far more profitable unto the kingdom than by our trades neer
at hand : As for example : suppose Pepper to be worth here two Shil-
lings the pound constantly, if then it be brought from the Dutch at Am-
sterdam, the Merchant may give there twenty pence the pound, and gain
well by the bargain, but if he fetch this Pepper from the East-Indies,
he must not give above three pence the pound at the most, which is a
mighty advantage, not only in that part which serveth for our own use,
but also for that great quantity which (from hence) we transport yearly
unto divers other Nations to be sold at a higher price: whereby it is
plain, that we make a far greater stock by gain upon these Indian Com-
modities, than those Nations doe where they grow, and to whom they
properly appertain, being the natural wealth of their Countries. But
for the better understanding of this particular, we must ever distinguish
between the gain of the Kingdom, and the profit of the Merchant ; for
although the Kingdom payeth no more for this Pepper than is before
supposed, nor for any other commodity bought in forraign parts more
than the stranger receiveth from us for the same, yet the merchant
payeth not only that price, but also the fraight, ensurance, customes and
other charges which are exceeding great in these long voyages, but yet
all these in the Kingdoms accompt are but commutations among our
selves, and no privation of the Kingdom stock, which being duly con-
sidered, together with the support also of our other trades in our best
Shipping to Italy, France, Turkey, the East Countreys and other places,
by transporting and venting the wares which we bring yearly from the
East Indies; It may well stir up our utmost endeavours to maintain and
enlarge this great and noble business, so much importing the Publique
162 SEVENTEENTH CENTURY POLITICAL ECONOMY
wealth, Strength, and Happiness. Neither is there less honour and judg-
ment by growing rich (in this manner) upon the stock of other Nations,
than by an industrious encrease of our own means, especially when this
later is advanced by the benefit of the former, as we have found in the
East Indies by sale of much of our Tin, Cloth, Lead and other Commod-
ities, the vent thereof doth daily encrease in those Countreys which for-
merly had no use of our wares.
9. It would be very beneficial to export money as well as wares,
being done in trade only, it would encrease our Treasure; but of this
I write more largely in the next Chapter to prove it plainly.
10. It were policie and profit for the State to suffer manufactures
made of forraign Materials to be exposed custome-free, as Velvets and
all other wrought Silks, Fustians, thrown Silks and the like, it would
employ very many poor people, and much encrease the value of our
stock yearly issued into other Countreys, and it would (for this purpose)
cause the more forraign Materials to be brought in, to the improvement
of His Majesties Customes. I will here remember a notable increase
in our manufacture of winding and twisting only of forraign raw Silk,
which within 35 years to my knowledge did not employ more than 300.
people in the City and suburbs of London, where at this present time it
doth set on work above fourteen thousand souls, as upon diligent enquiry
hath been credibly reported unto His Majesties Commissioners for
Trade. And it is certain, that if the said forraign Commodities might
be exported from hence, free of customes, this manufacture would yet
encrease very much, and decrease as fast in Italy and the Netherlands.
But if any man allege the Dutch proverb, Live and let others live, I
answer, that the Dutchmen notwithstanding their own proverb, doe not
onely in these Kingdoms, encroach upon our livings, but also in other
forraign parts of our trade (where they have power) they do hinder
and destroy us in our lawful course of living, hereby taking the bread
out of our mouth, which we shall never prevent by plucking the pot
from their nose, as of late years too many of us do practise to the great
hurt and dishonour of this famous Nation. We ought rather to imitate
former times in taking sober and worthy courses more pleasing to God
and suitable to our ancient reputation.
11. It is needful also not to charge the native commodities with
too great customes, lest by indearing them to the strangers use, it hinder
their vent. And especially forraign wares brought in to be transported
again should be favoured, for otherwise that manner of trading (so
SEVENTEENTH CENTURY POLITICAL ECONOMY 163
much importing the good of the Common wealth) cannot prosper nor
subsist. But the Consumption of such forraign wares in the Realm may
be the more charged, which will turn to the profit of the Kingdom in
the Ballance of the Trade, and thereby also enable the King to lay up
the more Treasure out of his yearly incomes, as of this particular I in-
tend to write more fully in its proper place, where I shall shew how
much money a Prince may conveniently lay up without the hurt of his
subjects.
12. Lastly, in all things we must endeavour to make the most we
can of our own, whether it be Natural or Artificial ; And forasmuch as
the people which live by the arts are far more in number than those
who are masters of the fruits, we ought the more carefully to main-
tain those endeavours of the multitude, in whom doth consist the great-
est strength and riches of King and Kingdom : for where the people are
many, and the arts good, there the traffique must be great, and the Coun-
trey rich. The Italians employ a greater number of people, and get
more money by their industry and manufactures of the raw Silks of the
Kingdom of Cicilia, than the King of Spain and his subjects have by
the revenue of this rich commodity. But what need we fetch the ex-
ample so far, when we know that our own natural wares do not yield
so much profit as our industry? For Iron ore in the Mines is of no
great worth, when it is compared with the employment and advantage
it yields being digged, tried, transported, bought, sold, cast into Ord-
nance, Muskets, and many other instruments of war for offence and de-
fence, wrought into Anchors, bolts, spikes, nayles and the like, for the
use of Ships, Houses, Carts, Coaches, Ploughs, and other instruments
for Tillage. Compare our Fleece-wools with our Cloth, which requires
shearing, washing, carding, spinning, Weaving, fulling, dying, dressing
and other trimmings, and we shall find these Arts more profitable than
the natural wealth, whereof I might instance other examples, but I will
not be more tedious, for if I would amplify upon this and the other par-
ticulars before written, I might find matter sufficient to make a large
volume, but my desire in all is only to prove what I propound with
brevity and plainness. — Reprint from first edition.
164
JOHN LOCKE
WHETHER we consider natural reason, which tells us that men, be-
ing once born, have a right to their preservation, and consequently to
meat and drink, and such other things as nature affords for their subsist-
ence; or revelation, which gives us an account of those grants God made
of the world to Adam, and to Noah, and to his sons, it is very clear that
God, as King David says, Psl. cxv. 16, "has given the earth to the
children of men ;" given to mankind in common. But this being sup-
posed, it seems to some a very great difficulty, how any one should ever
come to have a property in any thing. I will not content myself to an-
swer, that if it be difficult to make out property upon a supposition, that
God gave the world to Adam, and his posterity in common, it is impos-
sible that any man, but one universal monarch, should have any property
upon a supposition that God gave the world to Adam, and his heirs in
succession, exclusive of all the rest of his posterity. But I shall en-
deavor to shew, how men might come to have a property in several parts
of that which God gave to mankind in common, and that without any
express compact of all the commoners.
God, who hath given the world to men in common, hath also given
them reason to make use of it to the best advantage of life, and con-
venience. The earth, and all that is therein, is given to men for the sup-
port and comfort of their being. And though all the fruits it naturally
produces, and beasts it feeds, belonged to mankind in common, as they
are produced by the spontaneous hand of nature ; and nobody has orig-
inally a private dominion, exclusive of the rest of mankind, in any of
them, as they are thus in their natural state : yet being given for the use
of men, there must of necessity be a means to appropriate them some
way or other, before they can be of any use, or at all beneficial to any
particular man. The fruit, or venison, which nourishes the wild Indian,
who knows no inclosure, and is still a tenant in common, must be
SEVENTEENTH CENTURY POLITICAL ECONOMY 165
his, and so his, i. e., a part of him, that another can no longer have any
right to it, before it can do him any good for the support of life.
Though the earth, and all inferior creatures, be common to all
men, yet every man has a property in his own person: this no body
has any right to but himself. The labour of his body, and the work of
his hands, we may say, are properly his. Whatsoever then he removes
of the state nature has provided, and left It in, he hath mixed his labours
with, and joined to it something that is his own, and thereby makes it
his property. It being by him removed from the common state nature
hath placed it in, it hath by this labour something annexed to it, that
excludes the common right of other men. For this labour being the
unquestionable property of the labourer, no man but he can have a
right to what is once joined to, at least where there is enough, and as
good, left in common for others.
He that is nourished by the acorns he picks upon an oak, or the
apples he gathers from the trees in the wood, has certainly appropriated
them to himself. No body can deny but the nourishment is his. I ask
then, when did they begin to be his? when he digested? or when he
eats? or when he boiled? or when he brought them home? or when
he picked them up ? and it is plain, if the first gathering made them not
his, nothing else could. That labour put a distinction between them and
the common : that added something to them more than nature, the com-
mon mother of all, had done ; and so they became his private right. And
will anyone say, he had no right to those acorns or apples he thus appro-
priated, because he had not the consent of all mankind to make them
his ? Was it a robbery thus to assume to himself what belonged to all in
common? If such a consent as that was necessary, man had starved,
notwithstanding the plenty God had given him. We see in commons,
which remain so by compact, that it is the taking any part of what is
common, and removing it out of the state nature leaves it in, which be-
gins the property : without which the common is of no use. And the
taking of this or that part, does not depend on the express consent of all
the commoners. Thus the grass my horse has bit : the turfs my servant
has cut ; and the ore I have digged in my place, where I have a right to
them in common with others, become my property, without the assigna-
tion or consent of any body. The labour that was mine, removing them
out of that common state they were in, hath fixed my property in them.
By making an explicit consent of every commoner necessary in
any one's appropriation to himself any part of what is given in common ;
166 SEVENTEENTH CENTURY POLITICAL ECONOMY
children or servants could not cut the meat, which their father or master
had provided for them in common, without assigning to every one his
peculiar part. Though the water running in the fountain be every
one's, yet who can doubt, but that in the pitcher is his only who drew
it out? His labour hath taken it out of the hands of nature, where it
was common, and belonged equally to all her children, and hath thereby
appropriated it to himself.
Thus this law of reason makes the deer that Indian's who hath
killed it ; it is allowed to be his goods, who has bestowed his labour upon
it, though before it was the common right of everyone. And amongst
those who are counted the civilized part of mankind, who have made
and multiplied positive laws to determine property, this original law of
nature, for the beginning of property, in what was before common, still
takes place ; and by virtue thereof, what fish any one catches in the ocean,
and great and still remaining common of mankind ; or what ambergrise
any one takes up here, is by the labour that removes it out of that com-
mon state nature left it in, made his property, who takes that pains about
it. And even amongst us, the hare that any one is hunting, is thought
his who pursues her during the chase: for being a beast that is still
looked upon as common, and no man's private possession; whosoever
has employed so much labour about any of that kind, as to find and
pursue her, has thereby removed her from the state of nature, wherein
she was common, and hath begun a property.
It will perhaps be objected to this, that " if gathering the acorns,
or other fruits of the earth, &c. makes a right to them, then can anyone
ingross as much as he will." To which I answer, Not so. The same
law of nature, that does by this means give us property, does also bound
that property too. "God has given us all things richly," i Tim. vi. 12,
is the voice of reason confirmed by inspiration. But how far has he
given it to us? To enjoy. As much as anyone can make use of to any
advantage of lite before it spoils, so much be may by his labour fix a
property in: whatever is beyond this, is more than his share, and be-
longs to others. Nothing was made by God for man to spoil or destroy.
And thus, considering the plenty of natural provisions there was a long
time in the world, and a few spenders ; and to how small a part of that
provision the industry of any man could extend itself, and ingross it to
the prejudice of others ; especially keeping within the bounds, set by rea-
son, of what might serve for his use ; there could then be little room for
quarrels or contentions about property so established.
SEVENTEENTH CENTURY POLITICAL ECONOMY 167
But the chief matter of property being now not the fruits of the
earth, and the beasts that subsist on it, but the earth itself ; as that which
takes in and carries with it all the rest ; I think it is plain, that property
in that too is acquired as the former. As much land as a man tills, plants,
improves, cultivates, and can use the product of, so much is his property.
He by his labour does, as it were, inclose it from the common. Nor will
it invalidate his right, to say everybody else has an equal title to it ; and
therefore he cannot appropriate, he cannot inclose, without the consent
of all his fellow commoners, all mankind. God, when he gave the world
in common to all mankind, commanded man also to labour, and the pen-
ury of his condition required it of him. God and his reason commanded
him to subdue the earth, i. e. improve it for the benefit of life, and therein
lay out something upon it that was his own, his labour. He that in
obedience to this command of God subdued, tilled and sowed any part
of it, thereby annexed to it something that was his property, which an-
other had no title to, nor could without injury take it from him.
Nor was this appropriation of any parcel of land, by improving it,
any prejudice to any other man, since there was still enough, and as
good left; and more than the yet unprovided could use. So that, in
effect, there was never the less left for others because of his inclosure
for himself : for he that leaves as much as another can make use of, does
as good as take nothing at all. No body could think himself injured by
the drinking of another man, though he took a good draught, who had
a whole river of the same water left him to quench his thirst ; and the
case of land and water, where there is enough of both, is perfectly the
same.
God gave the world to men in common : but since he gave it to them
for their benefit, and the greatest conveniencies of life they were capa-
ble to draw from it, it cannot be supposed he meant it should always
remain common and uncultivated. He gave to the use of the industrious
and rational (and labour was to be his title to it) ; not to the fancy or
covetousness of the quarrelsome and contentious. He that had as good
left for his improvement as was already taken up, needed not to com-
plain, ought not to meddle with what was already improved by another's
labour: if he did, it is plain he desired the benefit of another's pains,
which he had no right to, and not the ground which God had given him
in common with others to labour on, and whereof there was as good left,
as that already possessed, and more than he knew what to do with, or
his industry could reach to.
168 SEVENTEENTH CENTURY POLITICAL, ECONOMY
It is true, in land that is common in England, or any other country,
where there is plenty of people under government, who have money and
commerce, no one can inclose or appropriate any part, without the con-
sent of all his fellow-commoners ; because this is left common by com-
pact, i. e. by the law of the land, which is not to be violated. And though
it be common, in respect to some men, it is not so to all mankind ; but is
the joint property of this country, or this parish. Besides, the remain-
der, after such inclosure, would not be as good to the rest of the com-
moners, as the whole was when they could all make use of the whole ;
whereas in the beginning and first peopling of the great common of the
world, it was quite otherwise. The law man was under, was rather for
appropriating. God commanded, and his wants forced him to labour.
That was his property which could not be taken from him wherever he
had fixed it. And hence subduing or cultivating the earth, and having
dominion, we see are joined together. The one gave title to the other.
So that God, by commanding to subdue, gave authority so far to appro-
priate ; and the condition of human life, which requires labour and ma-
terials to work on, necessarily introduces private possessions.
The measure of property nature has well set by the extent of men's
labour, and the conveniences of life : no man's labour could subdue, or
appropriate all; nor could his enjoyment consume more than a small
part ; so that it was impossible for any man, this way, to intrench upon
the right of another, or acquire to himself a property, to the prejudice
of his neighbour, who would still have room for as good and as large a
possession (after the other had taken out his) as before it was appro-
priated. This measure did confine every man's possession to a very
moderate proportion, and such as he might appropriate to himself, with-
out injury to any body, in the first ages of the world, when men were
in more danger to be lost, by wandering from their company, in the then
vast wilderness of the earth, than to be straitened for want of room to
plant in. And the same measure may be allowed still without prejudice
to any body, as full as the world seems : for supposing a man, or fam-
ily, in the state they were "at first peopling of the world by the children
of Adam, or Noah ; let him plant in some inland, vacant places of Amer-
ica, we shall find that the possessions he could make himself, upon the
measures we have given, would not be very large, nor, even to this day,
prejudice the rest of mankind, or give them reason to complain or think
themselves injured by this man's incroachment ; though the race of men
have now spread themselves to all the corners of the world, and do infin-
SEVENTEENTH CENTURY POLITICAL ECONOMY 169
itely exceed the small number at the beginning. Nay, the extent
of ground is of so little value, without labour, that I have heard it
affirmed, that in Spain itself a man may be permitted to plough, sow
and reap, without being disturbed, upon land he has no other title to,
but only his making use of it. But, on the contrary, the inhabitants
think themselves beholden to him, who, by his industry on neglected,
and consequently waste land, has increased the stock of corn, which they
wanted. But be this as it will, which I lay no stress on; this I dare
boldly affirm, that the same rule of propriety, (viz.) that every man
should have as much as he could make use of, would hold still in the
world, without straitening any body ; since there is land enough in the
world to suffice double the inhabitants, had not the invention of money,
and the tacit of men to put a value on it, introduced (by consent) larger
possessions, and a right to them ; which, how it has done, I shall by and
by shew more at large.
This is certain, that in the beginning, before the desire of having
more than man needed, had altered the intrinsic value of things, which
depends only on their usefulness to the life of man ; or had agreed, that a
little piece of yellow metal, which would keep without wasting or decay,
should be worth a great piece of flesh, or a whole heap of corn ; though
men had a right to appropriate, by their labour, each one to himself, as
much of the things of nature, as he could use : yet this could not be
much, nor to the prejudice of others, where the same plenty was still
left to those who would use the same industry. To which let me add,
that he who appropriates land to himself by his labour, does not lessen,
but increase the common stock of mankind : for the provisions serving
to the support of human life, produced by one acre of inclosed and culti-
vated land, are (to speak much within compass) ten times more than
those which are yielded by one acre of land of an equal richness lying
waste in common. And therefore he that incloses land, and has a
greater plenty of the conveniences of life from ten acres, than he could
have from an hundred left to nature, may truly be said to give ninety
acres to mankind : for his labour now supplies him with provisions out
of ten acres, which were but the product of an hundred lying in com-
mon. I have here rated the improved land very low, in making its prod-
uct but as ten to one, when it is much nearer an hundred to one : for I
ask, whether in the wild woods and uncultivated waste of America, left
to nature, without any improvement, tillage or husbandry, a thousand
acres yield the needy and wretched inhabitants as many conveniences
V 6-11
170 SEVENTEENTH CENTURY POLITICAL ECONOMY
of life, as ten acres of equally fertile land do in Devonshire, where they
are well cultivated.
Before the appropriation of land, he who gathered as much of the
wild fruit, killed, caught, or tamed, as many of the beasts, as he could ;
he that so employed his pains about any of the spontaneous products of
nature, as any way to alter them from the state which nature put them
in, by placing any of his labour on them, did thereby acquire a property
in them ; but if they perished, in his possession, without their due use ;
if the fruits rotted, or the venison putrified, before he could spend it,
he offended against the common law of nature, and was liable to be pun-
ished; he invaded his neighbour's share, for he had no right, farther
than his use called for any of them, and they might serve to afford his
conveniences of life.
The same measures governed the possession of land too : whatso-
ever he tilled and reaped, laid up and made use of, before it spoiled, that
was his peculiar right; whatsoever he enclosed, and could feed, and
make use of, the cattle and product was also his. But if either the grass
of his inclosure rotted on the ground, or the fruit of his planting per-
ished without gathering, and laying up ; this part of the earth, notwith-
standing his inclosure, was still to be looked .on as waste, and might
be the possession of any other. Thus, at the beginning, Cain might take
as much ground as he could till, and make it his own land, and yet leave
enough to Abel's sheep to feed on: a few acres would serve for their
possessions. But as families increased, and industry enlarged their
stocks, their possessions enlarged with the need of them ; but yet it was
commonly without any fixed property in the ground they made use of,
till they incorporated, settled themselves together, and built cities ; and
then, by consent, they came in time, to set out the bounds of their dis-
tinct territories, and agree on limits between them and their neighbors ;
and by laws within themselves, settled the properties of those of the
same society : for we see, that in that part of the world which was first
inhabited, and therefore like to be best peopled, even as low down as
Abraham's time, they wandered with their flocks and their herds, which
was their substance, freely up and down; and this Abraham did in a
country where he was a stranger. Whence it is plain, that at least a
great part of the land lay in common ; that the inhabitants valued it not,
nor claimed property in any more than they made use of. But when
there was not room enough in the same place, for their herds to feed to-
gether, they by consent, as Abraham and Lot did, Gen. xiii. 5, separated
SEVENTEENTH CENTURY POLITICAL ECONOMY 171
and enlarged their pasture, where it best liked them. And for the same
reason Esau went from his father, and his brother, and planted in Mount
Seir, Gen. xxxvi. 6.
And thus, without supposing any private dominion, and property in
Adam, over all the world, exclusive of all other men, which can no way
be proved, nor any one's property be made out from it ; but supposing
the world given, as it were, to the children of men in common, we see
how labour could make men distinct titles to several parcels of it, for
their private uses ; wherein there could be no doubt of right, no room
for quarrel.
172
EIGHTEENTH CENTURY PHILOSOPHY
BERKELEY
OUR INTRODUCTION to modern philosophy in this volume is a suffi-
cient preface to the philosophy of the eighteenth century.
Berkeley was born at Kilkenny, Ireland, in March, 1685. He en-
tered Trinity College, Dublin, in 1700, and remained there for the next
thirteen years.
Locke and Descartes were the best known philosophers at that time
and Berkeley was much interested in both. In 1709 he published his
Essay towards a New Theory of Vision. In this he argued that all that
is actually given us by sight is a color sensation — not distance, nor even
space dimensions. In 1710 he published his Principles of Human
Knowledge. Locke had declared that we get all our knowledge from
sensations and our reflections upon them — that we can have no definite
idea of substances, but must suppose them in order to have something
to support the qualities given us in sensation. Berkeley went farther
than this. He argues that the only things we know are mental and the
only cause of things we know is our own will, which, too, is mental,
and concludes that we have no right to suppose this unknown substance
to be anything but mental, that is, God. Later he further explained his
thought in his dialogues, considering the world of our sensations as in a
way the symbolic language of God. In 1713 he visited London, and
some years later Italy. In 1724 he was made Dean of Derry. He
planned a college in the Bermudas, and spent three years in Rhode
EIGHTEENTH CENTURY PHILOSOPHY 173
Island. Most of the rest of his life was spent in southern Ireland as
Bishop of Cloyne. He died at Oxford in January, 1753.
PRINCIPLES OF HUMAN KNOWLEDGE
1. IT is evident to any one who takes a survey of the objects of
human knowledge that they are either ideas actually imprinted on the
senses; or else such as are perceived by attending to the passions and
operations of the mind ; or lastly ideas formed by help of memory and
imagination— either compounding, dividing, or barely representing those
originally perceived in the aforesaid ways. — By sight I have the ideas
of light and colours, with their several degrees and variations. By
touch I perceive hard and soft, heat and cold, motion and resistance, and
of all these more and less either as to quantity or degree. Smelling fur-
nishes me with odours; the palate with tastes; and hearing conveys
sounds to the mind in all their variety of tone and composition. — And as
several of these are observed to accompany each other, they come to be
marked by one name, and so to be reputed as one THING. Thus, for ex-
ample, a certain colour, taste, smell, figure and consistence having been
observed to go together, are accounted one distinct thing, signified by
the name apple; other collections of ideas constitute a stone, a tree, a
book, and the like sensible things — which as they are pleasing or dis-
agreeable excite the passions of love, hatred, joy, grief, and so forth.
2. But, besides all that endless variety of ideas or objects of knowl-
edge, there is likewise something which knows or perceives them ; and
exercises divers operations, as willing, imagining, remembering, about
them. This perceiving, active being is what I call MIND, SPIRIT, SOUL,
or MYSELF. By which words I do not denote any one of my ideas, but
a thing entirely distinct from them, wherein they exist, or, which is the
same thing, whereby they are perceived — for the existence of an idea
consists in being perceived.
3. That neither our thoughts, nor passions, nor ideas formed by
the imagination, exist without the mind, is what everybody will allow. —
And to me it is no less evident that the various SENSATIONS, or ideas im-
printed on the sense, however blended or combined together (that is,
whatever objects they compose), cannot exist otherwise than in a mind
perceiving them — I think an intuitive knowledge may be obtained of this
by any one that shall attend to what is meant by the term exist when
174 EIGHTEENTH CENTURY PHILOSOPHY
applied to sensible things. The .table I write on I say exists, that is, I see
and feel it ; and if I were out of my study I should say it existed — mean-
ing thereby that if I was in my study I might perceive it, or that some
other spirit actually does perceive it. There was an odour, that is, it was
smelt ; there was a sound, that is, it was heard ; a colour or figure, and it
was perceived by sight or touch. This is all that I can understand by
these and the like expressions. — For as to what is said of the absolute
existence of unthinking things without any relation to their being per-
ceived, that is to me perfectly unintelligible. Their esse is percipi, nor
is it possible they should have any existence out of the minds or thinking
things which perceive them.
4. It is indeed an opinion strangely prevailing amongst men, that
houses, mountains, rivers, and in a word all sensible objects, have an
existence, natural or real, distinct from their being perceived by the un-
derstanding. But, with how great an assurance and acquiescence soever
this principle may be entertained in the world, yet whoever shall find in
his heart to call it in question may, if I mistake not, perceive it to in-
volve a manifest contradiction. For, what are the forementioned objects
but the things we perceive by sense? and what do we perceive besides
our own ideas or sensations? and is it not plainly repugnant that any
one of these, or any combination of them, should exist unperceived ?
5. If we thoroughly examine this tenet it will, perhaps, be found
at bottom to depend on the doctrine of abstract ideas. For can there be
a nicer strain of abstraction than to distinguish the existence of sensible
objects from their being perceived, so as to conceive them existing un-
perceived? Light and colours, heat and cold, extension and figures —
in a word the things we see and feel — what are they but so many sensa-
tions, notions, ideas, or impressions on the sense, and is it possible to
separate, even in thought, any of these from perception ? For my part,
I might as easily divide a thing from itself. I may, indeed, divide in
my thoughts, or conceive apart from each other, those things which,
perhaps, I never perceived by sense so divided. Thus, I imagine the
trunk of a human body without the limbs, or conceive the smell of a
rose without thinking on the rose itself. So far, I will not deny, I can
abstract — if that may properly be called abstraction which extends only
to the conceiving separately such objects as it is possible may really exist
or be actually perceived asunder. But my conceiving or imagining
power does not extend beyond the possibility of real existence or per-
ception. Hence, as it is impossible for me to see or feel anything without
EIGHTEENTH CENTURY PHILOSOPHY 175
an actual sensation of that thing, so it is impossible for me to conceive
in my thoughts any sensible thing or object distinct from the sensation
or perception of it. [In truth, the object and the sensation are the same
thing and cannot therefore be abstracted from each other.]
6. Some truths there are so near and obvious to the mind that a
man need only open his eyes to see them. Such I take this important
one to be, viz., that all the choir of heaven and furniture of the earth,
in a word all those bodies which compose the mighty frame of the world,
have not any subsistence without a mind — that their being is to be per-
ceived or known; that consequently so long as they are not actually per-
ceived by me, or do not exist in my mind or that of any other created
spirit, they must either have no existence at all, or else subsist in the
mind of some Eternal Spirit — it being perfectly unintelligible, and in-
volving all the absurdity of abstraction, to attribute to any single part of
them an existence independent of a spirit. To be convinced of which,
the reader need only reflect, and try to separate in his own thoughts the
being of a sensible thing from its being perceived.
7. From what has been said it is evident there is not any other
Substance than SPIRIT, or that 'which perceives. But, for the fuller dem-
onstration of this point, let it be considered the sensible qualities are
colour, figure, motion, smell, taste, &c., i. e., the ideas perceived by
sense. Now, for an idea to exist in an unperceiving thing is a manifest
contradiction ; for to have an idea is all one as to perceive ; that there-
fore wherein colour, figure, &c. exist must perceive them; hence it is
clear there can be no unthinking substance or substratum of those ideas.
8. But, say you, though the ideas themselves do not exist with-
out the mind, yet there may be things like them, whereof they are copies
or resemblances, which things exist without the mind in an unthinking
substance. I answer, an idea can be like nothing but an idea ; a colour
or figure can be like nothing but another colour or figure. If we look
but never so little into our thoughts, we shall find it impossible for us
to perceive a likeness except only between our ideas. Again, I ask
whether those supposed originals or external things, of which our ideas
are the pictures or representations, be themselves perceivable or no? If
they are, then they are ideas and we have gained our point; but if
you say they are not, I appeal to any one whether it be sense to assert a
colour is like something which is invisible ; hard or soft, like something
which is intangible ; and so of the rest.
9. Some there are who make a distinction betwixt primary and
176 EIGHTEENTH CENTURY PHILOSOPHY
secondary qualities. By the former they mean extension, figure, motion,
rest, solidity, impenetrability, and number ; by the latter they denote all
other sensible qualities, as colours, sounds, tastes, and so forth. The
ideas we have of these last they acknowledge not to be the resemblances
of anything existing without the mind, or unperceived, but they will
have our ideas of the primary qualities to be patterns or images of things
which exist without the mind, in an unthinking substance which they
call Matter. — By Matter, therefore, we are to understand an inert, sense-
less substance, in which extension, figure and motion do actually
subsist. But it is evident, from what we have already shewn, that ex-
tension, figure, and motion are only ideas existing in the mind, and that
an idea can be like nothing but another idea, and that consequently nei-
ther they nor their archetypes can exist in an unperceiving substance.
Hence, it is plain that the very notion of what is called Matter or cor-
poreal substance involves a contradiction in it.
10. They who assert that figure, motion, and the rest of the pri-
mary or original qualities do exist without the mind, in unthinking
substances, do at the same time acknowledge that colours, sounds, heat,
cold, and suchlike secondary qualities, do not — which they tell us are
sensations existing in the mind alone, that depend on and are occa-
sioned by the different size, texture, and motion of the minute particles
of matter. This they take for an undoubted truth, which they can dem-
onstrate beyond all exception. Now, if it be certain that those original
qualities are inseparably united with the other sensible qualities, and
not, even in thought, capable of being abstracted from them, it plainly
follows that they exist only in the mind. But I desire any one to reflect
and try whether he can, by any abstraction of thought, conceive the
extension and motion of a body without all other sensible qualities. For
my own part, I see evidently that it is not in my power to frame an
idea of a body extended and moving, but I must withal give it some
colour or other sensible quality which is acknowledged to exist only
in the mind. In short, extension, figure, and motion, abstracted from all
other qualities, are inconceivable. Where therefore the other sensible
qualities are, there must these be also, to wit, in the mind and no-
where else.
11. Again, great and small, swift and slow, are allowed to exist
nowhere without the mind, being entirely relative, and changing as
the frame of position of the organs of sense varies. The extension
therefore which exists without the mind is neither great nor small, the
EIGHTEENTH CENTURY PHILOSOPHY in
motion neither swift nor slow, that is, they are nothing at all. But, say
you, they are extension in general, and motion in general: thus we
see how much the tenet of extended moveable substances existing with-
out the mind depends on that strange doctrine of abstract ideas. And
here I cannot but remark how nearly the vague and indeterminate de-
scription of Matter or corporeal substance, which the modern philos-
ophers are run into by their own principles, resembles that antiquated
and so much ridiculed notion of materia prima, to be met with in Aris-
totle and his followers. Without extension solidity cannot be con-
ceived; since therefore it has been shewn that extension exists not in
an unthinking substance, the same must also be true of solidity.
12. That number is entirely the creature of the mind, even though
the other qualities be allowed to exist without, will be evident to who-
ever considers that the same thing bears a different denomination of
number as the mind views it with different respects. Thus, the same
extension is one, or three, or thirty-six, according as the mind considers
it with reference to a yard, a foot, or an inch. Number is so visibly
relative and dependent on men's understanding, that it is strange to
think how any one should give it an absolute existence without the
mind. We say one book, one page, one line, etc. ; all these are equally
units, though some contain several of the others. And in each instance,
it is plain, the unit relates to some particular combination of ideas arbi-
trarily put together by the mind.
13. Unity I know some will have to be a simple or uncompounded
idea, accompanying all other ideas into the mind. That I have any
such idea answering the word unity I do not find ; and if I had, methinks
I could not miss finding it : on the contrary, it should be the most fa-
miliar to my understanding, since it is said to accompany all other ideas,
and to be perceived by all the ways of sensation and reflexion. To say
no more, it is an abstract idea.
14. I shall further add, that, after the same manner as modern
philosophers prove certain sensible qualities to have no existence in
Matter, or without the mind, the same thing may be likewise proved
of all other sensible qualities whatsoever. Thus, for instance, it is said
that heat and cold are affections only of the mind, and not at all pat-
terns of real beings existing in the corporeal substances which excite
them, for that the same body which appears cold to one hand seems
warm to another. Now, why may we not as well argue that figure and
extension are not patterns or resemblances of qualities existing in Mat-
178 EIGHTEENTH CENTURY PHIIX)SOPHY
ter, because to the same eye at different stations, or eyes of a different
texture at the same station, they appear various, and cannot therefore
be the images of anything settled and determinate without the mind?
Again, it is proved that sweetness is not really in the sapid thing, be-
cause the thing remaining unaltered the sweetness is changed into
bitter, as in case of a fever or otherwise vitiated palate. Is it not as
reasonable to say that motion is not without the mind, since if the suc-
cession of ideas in the mind become swifter the motion, it is acknowl-
edged, shall appear slower without any alteration in any external object.
15. In short, let any one consider those arguments which are
thought manifestly to prove that colours and tastes exist only in the
mind, and he shall find they may with equal force be brought to prove
the same thing of extension, figure, and motion. — Though it must be
confessed this method of arguing does not so much prove that there
is no extension or colour in an outward object, as that we do not know
by sense which is the true extension or colour of the object. But the
arguments foregoing plainly shew it to be impossible that any colour or
extension at all, or other sensible quality whatsoever, should exist in an
unthinking subject without the mind, or in truth, that there should be
any such thing as an outward object.
16. But let us examine a little the received opinion. — It is said
extension is a mode or accident of Matter, and that Matter is the sub-
stratum that supports it. Now I desire that you would explain to me
what is meant by Matter's supporting extension. Say you, I have no
idea of Matter and therefore cannot explain it. I answer, though you
have no posititve, yet, if you have any meaning at all, you must at least
have a relative idea of Matter ; though you know not what it is, yet you
must be supposed to know what relation it bears to accidents, and what
is meant by its supporting them. It is evident "support" cannot here
be taken in its usual or literal sense — as when we say that pillars sup-
port a building ; in what sense therefore must it be taken ?
17. If we inquire into what the most accurate philosophers de-
clare themselves to mean by material substance, we shall find them
acknowledge they have no other meaning annexed to those sounds but
the idea of being in general, together with the relative notion of its sup-
porting accidents. The general idea of Being appeareth to me the most
abstract and incomprehensible of all other; and as for its supporting
accidents, this, as we have just now observed, cannot be understood in
the common sense of those words ; it must therefore be taken in some
EIGHTEENTH CENTURY PHILOSOPHY 179
other sense, but what that is they do not explain. So that when I con-
sider the two parts or branches which make the signification of the
words material substance, I am convinced there is no distinct meaning
annexed to them. But why should we trouble ourselves any farther,
in discussing this material substratum or "support" of figure, and mo-
tion, and other sensible qualities? Does it not suppose they have an
existence without the mind ? And is not this a direct repugnancy, and
altogether inconceivable ?
1 8. But, though it were possible that solid, figured, moveable sub-
stances may exist without the mind, corresponding to the ideas we have
of bodies, yet how is it possible for us to know this ? Either we must
know it by Sense or by Reason. — As for our senses, by them we have
the knowledge only of our sensations, ideas, or those things that are
immediately perceived by sense, call them what you will : but they do
not inform us that things exist without the mind, or unperceived, like
to those which are perceived. This the Materialists themselves acknowl-
edge.— It remains therefore that if we have any knowledge at all of
external things, it must be by Reason inferring their existence from
what is immediately perceived by sense. But what reason can induce
us to believe the existence of bodies without the mind, from what we
perceive, since the very patrons of Matter themselves do not pretend
there is any necessary connexion betwixt them and our ideas? I say
it is granted on all hands — and what happens in dreams, frenzies, and
the like, puts it beyond dispute — that it is possible we might be affected
with all the ideas we have now, though there were no bodies existing
without resembling them. Hence, it is evident the supposition of exter-
nal bodies is not necessary for the producing our ideas; since it is
granted they are produced sometimes, and might possibly be produced
always in the same order we see them in at present, without their con-
currence.
19. But, though we might possibly have all our sensations with-
out them, yet perhaps it may be thought easier to conceive and explain
the manner of their production, by supposing eternal bodies in their
likeness rather than otherwise ; and so it might be at least probable there
are such things as bodies that excite their ideas in our minds. But
neither can this be said ; for, though we give the Materialists their ex-
ternal bodies, they by their own confession are never the nearer know-
ing how our ideas are produced; since they own themselves unable to
comprehend in what manner body can act upon spirit, or how it is possi-
180 EIGHTEENTH CENTURY PHILOSOPHY
ble it should imprint any idea in the mind. Hence it is evident the pro-
duction of ideas or sensations in our minds can be no reason why we
should suppose Matter or corporeal substances, since that is acknowl-
edged to remain equally inexplicible with or without this supposition.
If therefore it were possible for bodies to exist without the mind, yet
to hold they do so must needs be a very precarious opinion ; since it is
to suppose, without any reason at all, that God has created innumerable
beings that are entirely useless, and serve to no manner of purpose.
20. In short, if there were external bodies, it is impossible we
should ever come to know it ; and if there were not, we might have the
very same reasons to think there were that we have now. Suppose —
what no one can deny possible — an intelligence without the help of ex-
ternal bodies, to be affected with the same train of sensations or ideas
that you are, imprinted in the same order and with like vividness in
his mind. I ask whether that intelligence hath not all the reason to
believe the existence of corporeal substances, represented by his ideas,
and exciting them in his mind, that you can possibly have for believing
the same thing? Of this there can be no question — which one consider-
ation were enough to make any reasonable person suspect the strength
of whatever arguments he may think himself to have, for the existence
of bodies without the mind.
21. Were it necessary to add any farther proof against the Exist-
ence of Matter, after what has been said, I could instance several of
those errors and difficulties (not to mention impieties) which have
sprung from that tenet. It has occasioned numberless controversies and
disputes in philosophy, and not a few of far greater moment in religion.
But I shall not enter into the detail of them in this place, as well be-
cause I think arguments a posteriori are unnecessary for confirming
what has been, if I mistake not, sufficiently demonstrated a priori, as
because I shall hereafter find occasion to speak somewhat of them.
22. I am afraid I have given cause to think I am needlessly prolix
in handling this subject. For, to what purpose is it to dilate on that
which may be demonstrated with the utmost evidence in a line or two,
to any one that is capable of the least reflection ? It is but looking into
your own thoughts, and so trying whether you can conceive it possible
for a sound, or figure, or motion, or colour to exist without the mind or
unperceived. This easy trial may perhaps make you see that what you
contend for is a downright contradiction. Insomuch that I am content
to put the whole upon this issue : — If you can but conceive it possible
EIGHTEENTH CENTURY PHILOSOPHY 181
for one extended moveable substance, or, in general, for any one idea,
or anything like an idea, to exist otherwise than in a mind perceiving it,
I shall readily give up the cause. And, as for all that compages of ex-
ternal bodies you contend for, I shall grant you its existence, though
you cannot either give me any reason why you believe it exists, or
assign any use to it when it is supposed to exist. I say, the bare possi-
bility of your opinions being true shall pass for an argument that it is so.
23. But, say you, surely there is nothing easier than for me to
imagine trees, for instance, in a park, or books existing in a closet, and
nobody by to perceive them. I answer, you may do so ; there is no diffi-
culty in it ; but what is all this, I beseech you, more than framing in your
mind certain ideas which you call books and trees, and at the same time
omitting to frame the idea of any one that may perceive them ? But do
not you yourself perceive or think of them all the while ? This there-
fore is nothing to the purpose: it only shews you have the power of
imagining or forming ideas in your mind ; but it does not shew that you
can conceive it possible the objects of your thought may exist without
the mind. To make out this, it is necessary that you conceive them ex-
isting unconceived or unthought of, which is a manifest repugnancy.
When we do our utmost to conceive the existence of external bodies,
we are all the while only contemplating our own ideas. But the mind,
taking no notice of itself, is deluded to think it can and does conceive
bodies existing unthought of or without the mind, though at the same
time they are apprehended by or exist in itself. A little attention will
discover to any one the truth and evidence of what is here said, and
make it unnecessary to insist on any other proofs against the existence
of material substance.
24. It is very obvious, upon the least inquiry into our own
thoughts, to know whether it be possible for us to understand what is
meant by the absolute existence of sensible objects in themselves, or
without the mind. To me it is evident those words mark out either a
direct contradiction, or else nothing at all. And to convince others of
this, I know no readier or fairer way than to entreat they would calmly
attend to their own thoughts ; and if by this attention the emptiness or
repugnancy of those expressions does appear, surely nothing more is
requisite for their conviction. It is on this therefore that I insist, to wit,
that the absolute existence of unthinking things are words without a
meaning, or which include a contradiction. This is what I repeat and
182 EIGHTEENTH CENTURY PHILOSOPHY
inculcate, and earnestly recommend to the attentive thoughts of the
reader.
25. All our ideas, sensations, motions, or the things which we
perceive, by whatsoever names they may be distinguished, are visibly
inactive — there is nothing of Power or Agency included in them. So
that one idea or object of thought cannot produce or make any altera-
tion in another. To be satisfied of the truth of this, there is nothing
else requisite but a bare observation of our ideas. For, since they and
every part of them exist only in the mind, it follows that there is noth-
ing in them but what is perceived : but whoever shall attend to his ideas,
whether of sense or reflection, will not perceive in them any power or
activity; there is, therefore, no such thing contained in them. A little
attention will discover to us that the very being of an idea implies pas-
siveness and inertness in it, insomuch that it is impossible for an idea
to do anything, or, strictly speaking, to be the cause of anything : neither
can it be the resemblance or pattern of any active being, as is evident
from sect. 8. Whence it plainly follows that extension, figure, and mo-
tion cannot be the cause of our sensations. To say, therefore, that these
are the effects of powers resulting from the configuration, number, mo-
tion, and size of corpuscles, must certainly be false.
26. We perceive a continual succession of ideas; some are anew
excited, others are changed or totally disappear. There is therefore
some Cause of these ideas, whereon they depend, and which produces
and changes them. That this cause cannot be any quality, or idea, or
combination of ideas is clear from the preceding section. It must there-
fore be a substance ; but it has been shown that there is no corporeal or
material substance: it remains therefore that the cause of ideas is an
incorporeal active substance or Spirit.
27. A Spirit is one simple, undivided, active being — as it perceives
ideas it is called the Understanding, and as it produces or otherwise
operates about them it is called the Will. Hence there can be no idea
formed of a soul or spirit; for, all ideas whatever, being passive and
inert, (vid. sect. 25,) cannot represent unto us, by way of image or like-
ness, that which acts. A little attention will make it plain to any one
that to have an idea which shall be like that active principle of motion
and change of ideas is absolutely impossible. Such is the nature of
Spirit, or that which acts, that it cannot be of itself perceived, but only
by the effects which it produceth. — If any man shall doubt of the truth
of what is here delivered, let him but reflect and try if we can frame the
EIGHTEENTH CENTURY PHILOSOPHY 183
idea of any Power or Active Being ; and whether he has ideas of two
principal powers, marked by the names Will and Understanding, dis-
tinct from each other, as well as from a third idea of Substance or Being
in general, with a relative motion of its supporting or being the subject
of the aforesaid powers — which is signified by the name Soul or Spirit.
This is what some hold ; but, so far as I can see, the words will, soul,
spirit, do not stand for different ideas, or, in truth, for any idea at all,
but for something which is very different from ideas, and which, being
an Agent, cannot be like unto, or represented by, any idea whatsoever.
[Though it must be owned at the same time that we have some notion
of soul, spirit, and the operation of the mind ; such as willing, loving,
hating — inasmuch as we know or understand the meaning of these
words.]
28. I find I can excite ideas in my mind at pleasure, and vary and
shift the scene as oft as I think fit. It is no more than willing, and
straightway this or that idea arises in my fancy ; and by the same power
it is obliterated and makes way for another. This making and unmak-
ing of ideas doth very properly denominate the mind active. Thus
much is certain and grounded on experience : but when we talk of un-
thinking agents, or of exciting ideas exclusive of Volition, we only
amuse ourselves with words.
29. But, whatever power I may have over my own thoughts, I
find the ideas actually perceived by Sense have not a like dependence
on my will. When in broad daylight I open my eyes, it is not in my
power to choose whether I shall see or no, or to determine what par-
ticular objects shall present themselves to my view ; and so likewise as
to the hearing and other senses, the ideas imprinted on them are not
creatures of my will. There is therefore some other Will or Spirit that
produces them.
30. The ideas of Sense are more strong, lively, and distinct than
those of the Imagination; they have likewise a steadiness, order, and
coherence, and are not excited at random, as those which are the effects
of human wills often are, but in a regular train or series — the admirable
connexion whereof sufficiently testifies the wisdom and benevolence of
its Author. Now the set rules or established methods wherein the Mind
we depend on excites in us the ideas of sense, are called the laws of na-
ture; and these we learn by experience, which teaches us that such and
such ideas are attended with such and such other ideas, in the ordinary
course of things.
134 EIGHTEENTH CENTURY PHILOSOPHY
31. This gives us a sort of foresight which enables us to regulate
our actions for the benefit of life. And without this we should be eter-
nally at a loss ; we could not know how to act anything that might pro-
cure us the least pleasure, or remove the least pain of sense. That food
nourishes, sleep refreshes, and fire warms us ; that to sow in the seed-
time is the way to reap in the harvest ; and in general that to obtain such
or such ends, such or such means are conducive — all this we know, not
by discovering any necessary connexion between our ideas, but only by
the observation of the settled laws of nature, without which we should
be all in uncertainty and confusion, and a grown man no more know
how to manage himself in the affairs of life than an infant just born.
32. And yet this consistent uniform working, which so evidently
displays the goodness and wisdom of that Governing Spirit whose Will
constitutes the laws of nature, is so far from leading our thoughts to
Him, that it rather sends them wandering after second causes. For,
when we perceive certain ideas of Sense constantly followed by other
ideas, and we know this is not of our own doing, we forthwith attribute
power and agency to the ideas themselves, and make one the cause of
another, than which nothing can be more absurd and unintelligible.
Thus, for example, having observed that when we perceive by sight a
certain round luminous figure we at the same time perceive by touch
the idea or sensation called heat, we do from thence conclude the sun
to be the cause of heat. And in like manner perceiving the motion and
collision of bodies to be attended with sound, we are inclined to think
the latter the effect of the former.
33. The ideas imprinted on the Senses by the Author of nature
are called real things: and those excited in the imagination being less
regular, vivid, and constant, are more properly termed ideas, or images
of things, which they copy and represent. But then our sensations, be
they never so vivid and distinct, are nevertheless ideas, that is, they exist
in the mind, or are perceived by it, as truly as the ideas of its own fram-
ing. The ideas of Sense are allowed to have more reality in them, that
is, to be more strong, orderly, and coherent than the creatures of the
mind ; but this is no argument that they exist without the mind. They
are also less dependent on the spirit, or thinking substance which per-
ceives them, in that they are excited by the will of another and more
powerful Spirit ; yet still they are ideas, and certainly no idea, whether
faint or strong, can exist otherwise than in a mind perceiving it.
HUME
DAVID HUME was born at Edinburgh in April, 1711. He studied
for a time at the university in the city and later began the reading of
law, but forsook it for philosophical pursuits. He published his "Treat-
ise on the Understanding" in 1739-40.
Berkeley had argued that the unknown something presupposed as
the cause of sensations must be similar in nature to the self we already
know and hence an intellectuality. Hume attacked all this and in fact
the possibility of all philosophy and all science by maintaining that there
is no self but the disconnected sensations and ideas of consciousness,
that the idea of cause and effect is simply the result of habit, that all
experience is personal, made up of the mental phenomena of the mo-
ment not necessarily related, and hence that all certain knowledge is
impossible.
About 1741 he became interested in political subjects and his essays
in that field were widely read. He argued against the idea that money,
instead of men and commodities, constitutes wealth, and as a conse-
quence against the principle that exports should exceed imports and
against restricted trade. Adam Smith later adopted many of these
ideas.
In 1751 he was appointed librarian of the Faculty of Advocates,
and turned his attention to history. His history of England was pub-
lished in the next ten years.
He became secretary to Lord Hertford, ambassador to France in
1763, and from 1767 to 1769 he was Under-Secretary of State. He
died in Edinburgh August 25, 1776.
AGAINST THE PRINCIPLE OF CAUSE AND EFFECT
I am sensible how abstruse all this reasoning must appear to the
generality of readers, who not being accustom'd to such profound re-
flections on the intellectual faculties of the mind, will be apt to reject
V 6-12
186 EIGHTEENTH CENTURY PHILOSOPHY
as chimerical whatever strikes not in with the common receiv'd notions,
and with the easiest and most obvious principles of philosophy. And no
doubt there are some pains requir'd to enter into these arguments ; tho'
perhaps very little are necessary to perceive the imperfection of every
vulgar hypothesis on this subject, and the little light, which philosophy
can yet afford us in such sublime and such curious speculations. Let
men be once fully perswaded of these two principles, That there is noth-
ing in any object, considered in itself, which can afford us a reason for
drawing a conclusion beyond it; and, That even after the observation of
the frequent or constant conjunction of objects, we have no reason to
draw any inference concerning any object beyond those of which we
have had experience; I say, let men be once fully convinc'd of these
two principles, and this will throw them so loose from all common sys-
tems, that they will make no difficulty of receiving any, which may
appear the most extraordinary. These principles we have found to be
sufficiently convincing, even with regard to our most certain reasonings
from causation : But I shall venture to affirm, that with regard to these
conjectural or probable reasonings they still acquire a new degree of
evidence.
First, Tis obvious, that in reasonings of this kind, 'tis not the
object presented to us, which, consider'd in itself, affords us any reason
to draw a conclusion concerning any other object or event. For as this
latter object is supposed uncertain, and as the uncertainty is deriv'd from
a conceal'd contrariety of causes in the former, were any of the causes
plac'd in the known qualities of that object, they wou'd no longer be
conceal'd, nor wou'd our conclusion be uncertain.
But, secondly, 'tis equally obvious in this species of reasoning, that
if the transference of the past to the future were founded merely on a
conclusion of the understanding, it cou'd never occasion any belief or
assurance. When we transfer contrary experiments to the future,
we can only repeat these contrary experiments with their particular
proportions; which cou'd not produce assurance in any single event,
upon which we reason, unless the fancy melted together all those images
that concur, and extracted from them one single idea or image, which is
intense and lively in proportion to the number of experiments from
which it is deriv'd, and their superiority above their antagonists. Our
past experience presents no determinate object; and as our belief, how-
ever faint, fixes itself on a determinate object, 'tis evident that the belief
arises not merely from the transference of past to future, but from some
EIGHTEENTH CENTURY PHILOSOPHY 187
operation of the fancy conjoin'd with it. This may lead us to conceive
the manner in which that faculty enters into all our reasonings.
I shall conclude this subject with two reflections, which may de-
serve our attention. The first may be explain'd after this manner. When
the mind forms a reasoning concerning any matter of fact, which is only
probable, it casts its eye backward upon past experience, and transfer-
ring it to the future, is presented with so many contrary views of its
object, of which those that are of the same kind uniting together, and
running into one act of the mind, serve to fortify and inliven it. But
suppose that this multitude of views or glimpses of an object proceeds
not from experience, but from a voluntary act of the imagination ; this
effect does not follow, or at least, follows not in the same degree. For
tho' custom and education produce belief by such a repetition, as is not
deriv'd from experience, yet this requires a long tract of time, along
with a very frequent and undesign'd repetition. In general we may
pronounce, that a person, who wou'd voluntarily repeat any idea in his
mind, tho' supported by one past experience, wou'd be no more inclin'd
to believe the existence of its object, than if he had contented himself
with one survey of it. Beside the effect of design ; each act of the mind,
being separate and independent, has a separate influence, and joins not
its force with that of its fellows. Not being united by any common ob-
ject, producing them, they have no relation to each other; and conse-
quently make no transition or union of forces. This phenomenon we
shall understand better afterwards.
My second reflection is founded on those large probabilities, which
the mind can judge of, and the minute differences it can observe betwixt
them. When the chances or experiments on one side amount to ten
thousand, and on the other to ten thousand and one, the judgment gives
the preference to the latter, upon account of that superiority; tho' 'tis
plainly impossible for the mind to run over every particular view, and
distinguish the superior vivacity of the image arising from the superior
number, where the difference is so inconsiderable. We have a parallel
instance in the affections. 'Tis evident, according to the principles above-
mention'd, that when an object produces any passion in us, which varies
according to the different quantity of the object ; I say, 'tis evident, that
the passion, properly speaking, is not a simple emotion, but a com-
pounded one, of a great number of weaker passions, deriv'd from a view
of each part of the object. For otherwise 'twere impossible the passion
shou'd encrease by the encrease of these parts. Thus a man, who desires
188 EIGHTEENTH CENTURY PHILOSOPHY
a thousand pound, has in reality a thousand or more desires, which unit-
ing together, seem to make only one passion ; tho' the composition evi-
dently betrays itself upon every alteration of the object, by the preference
he gives to the larger number, if superior only by an unit. Yet nothing
can be more certain, than that so small a difference wou'd not be dis-
cernible in the passions, nor wou'd render them distinguishable
from each other. The difference, therefore, of our conduct in pre-
ferring the greater number depends not upon our passions, but
upon custom, and general rules. We have found in a multitude of in-
stances, that the augmenting the numbers of any sum augments the pas-
sion, where the numbers are precise and the difference sensible. The
mind can perceive from its immediate feeling, that three guineas pro-
duce a greater passion than two ; and this it transfers to larger numbers,
because of the resemblance ; and by a general rule assigns to a thousand
guineas, a stronger passion than to nine hundred and ninety-nine. These
general rules we shall explain presently.
But beside these two species of probability, which are deriv'd from
an imperfect experience and from contrary causes, there is a third aris-
ing from ANALOGY, which differs from them in some material circum-
stances. According to the hypothesis above explain'd all kinds of rea-
soning from causes or effects are founded on two particulars, viz., the
constant conjunction of any two objects in all past experience, and the
resemblance of a present object to any one of them. The effect of these
two particulars is, that the present object invigorates and enlivens the
imagination; and the resemblance, along with the constant union, con-
veys this force and vivacity to the related idea ; which we are therefore
said to believe, or assent to. If you weaken either the union or resem-
blance, you weaken the principle of transition, and of consequence that
belief, which arises from it. The vivacity of the first impression cannot
be fully convey'd to the related idea, either where the conjunction of
their objects is not constant, or where the present impression does not
perfectly resemble any of those, whose union we are accustom'd to ob-
serve. In those probabilities of chance and causes above-explain'd, 'tis
the constancy of the union, which is diminish'd ; and in the probability
deriv'd from analogy, 'tis the resemblance only, which is affected. With-
out some degree of resemblance, as well as union, 'tis impossible there
can be any reasoning : but as this resemblance admits of many different
degrees, the reasoning becomes proportionately more or less firm and
certain. An experiment loses of its force, when tranferr'd to instances,
EIGHTEENTH CENTURY PHILOSOPHY 189
which are not exactly resembling; tho' 'tis evident it may still retain
as much as may be the foundation of probability, as long as there is any
resemblance remaining.
AGAINST PERSONAL IDENTITY
There are some philosophers who imagine we are every moment
intimately conscious of what we call our SELF; that we feel its existence
and its continuance in existence; and are certain, beyond the evidence
of a demonstration, both of its perfect identity and simplicity. The
strongest sensation, the most violent passion, say they, instead of dis-
tracting us from this view, only fix it the more intensely, and make us
consider their influence on self either by their pain or pleasure. To at-
tempt a farther proof of this were to weaken its evidence; since no
proof can be deriv'd from any fact, of which we are so intimately con-
scious ; nor is there any thing, of which we can be certain, if we doubt
of this.
Unluckily all these positive assertions are contrary to that very
experience, which is pleaded for them, nor have we any idea of self,
after the manner it is here explain'd. For from what impression cou'd
this idea be deriv'd? This question 'tis impossible to answer without
a manifest contradiction and absurdity; and yet 'tis a question, which
must necessarily be answer'd, if we wou'd have the idea of self pass for
clear and intelligible. It must be some one impression, that gives rise
to every real idea. But self or person is not any one impression, but
that to which our several impressions and ideas are 'suppos'd to have a
reference. If any impression gives rise to the idea of self, that impres-
sion must continue invariably the same, thro' the whole course of our
lives ; since self is suppos'd to exist after that manner. But there is no
impression constant and invariable. Pain and pleasure, grief and joy,
passions and sensations succeed each other, and never all exist at the
same time. It cannot, therefore, be from any of these impressions, or
from any other, that the idea of self is deriv'd ; and consequently there
is no such idea.
But farther, what must become of all our particular perceptions
upon this hypothesis ? All these are different, and distinguishable, and
separable from each other, and may be separately consider'd, and may
exist separately, and have no need of any thing to support their exist-
190 EIGHTEENTH CENTURY PHILOSOPHY
ence. After what manner, therefore, do they belong to self; and how
are they connected with it ? For my part, when I enter most intimately
into what I call myself, I always stumble on some particular perception
or other, of heat or cold, light or shade, love or hatred, pain or pleasure.
I never can catch myself at any time without a perception, and never
can observe any thing but the perception. When my perceptions are
remov'd for any time, as by sound sleep; so long am I insensible of
myself, and may truly be said not to exist. And were all my perceptions
remov'd by death, and cou'd I neither think, nor feel, nor see, nor love,
nor hate after the dissolution of my body. I shou'd be entirely annihi-
lated, nor do I conceive what is farther requisite to make me a perfect
non-entity. If any one upon serious and unprejudic'd reflection, thinks
he has a different notion of himself, I must confess I can reason no
longer with him. All I can allow him is, that he may be in the right as
well as I, and that we are essentially different in this particular. He
may, perhaps, perceive something simple and continu'd, which he calls
himself, tho' I am certain there is no such principle in me.
But setting aside some metaphysicians of this kind, I may venture to
affirm of the rest of mankind, that they are nothing but a bundle or col-
lection of different perceptions, which succeed each other with an
inconceivable rapidity, and are in a perpetual flux and movement. Our
eyes cannot turn in their sockets without varying our perceptions. Our
thought is still more variable than our sight; and all our other senses
and faculties contribute to this change ; nor is there any single power of
the soul, which remains unalterably the same, perhaps for one moment.
The mind is a kind of theater, where several perceptions successively
make their appearance; pass, re-pass, glide away, and mingle in an
infinite variety of postures and situations. There is properly no sim-
plicity in it at one time, nor identity in different ; whatever natural pro-
pension we may have to imagine that simplicity and identity. The
comparison of the theater must not lead us. They are the successive per-
ceptions only, that constitute the mind; nor have we the most distant
notion of the place, where these scenes are represented, or of the
materials, of which it is compos'd.
What then gives us so great a propension to ascribe an identity to
these successive perceptions, and to suppose ourselves possest of an
invariable and uninterrupted existence thro' the whole course of our
lives? In order to answer this question, we must distinguish betwixt
personal identity, as it regards our thought or imagination, and as it
EIGHTEENTH CENTURY PHILOSOPHY 191
regards our passions or the concern we take in ourselves. The first is
our present subject; and to explain it perfectly we must take the
matter pretty deep, and account for that identity, which we attribute
to plants and animals ; there being a great analogy betwixt it, and the
identity of a self or person.
We have a distinct idea of an object, that remains invariable and
uninterrupted thro' a suppos'd variation of time ; and this idea we call
that of identity or sameness. We have also a distinct idea of several
different objects existing in succession, and connected together by a
close relation ; and this to an accurate view affords as perfect a notion
of diversity, as if there was no manner of relation among the objects.
But tho' these two ideas of identity, and a succession of related objects
be in themselves perfectly distinct, and even contrary, yet 'tis certain,
that in our common way of thinking they are generally confounded
with each other. That action of the imagination, by which we consider
the uninterrupted and invariable object, and that by which we reflect on
the succession of related objects, are almost the same to the feeling, nor
is there much more effort of thought requir'd in the latter case than
in the former. The relation facilitates the transition of the mind from
one object to another, and renders its passage as smooth as if it con-
templated one continu'd object. This resemblance is the cause of the
confusion and mistake, and makes us substitute the notion of identity,
instead of that of related objects. However at one instant we may
consider the related succession as variable or interrupted, we are sure
the next to ascribe to it a perfect identity, and regard it as invariable
and uninterrupted. Our propensity to this mistake is so great from the
resemblance above-mention'd, that we fall into it before we are aware;
and tho' we incessantly correct ourselves by reflection, and return to a
more accurate method of thinking, yet we cannot long sustain our
philosophy, or take off this biass from the imagination. Our last
resource is to yield to it, and boldly assert that these different related
objects are in effect the same, however interrupted and variable. In
order to justify to ourselves this absurdity, we often feign some new
and unintelligible principle, that connects the objects together, and
prevents their interruption or variation. Thus we feign the continu'd
existence of the perceptions of our senses, to remove the interruption ;
and run into the notion of a soul, and self, and substance, to disguise
the variation. But we may farther observe, that where we do not give
rise to such a fiction, our propension to confound identity with relation
192 EIGHTEENTH CENTURY PHILOSOPHY
is so great, that we are apt to imagine something unknown and myster-
ious, connecting the parts, beside their relation ; and this I take to be
the case with regard to the identity we ascribe to plants and vegetables.
And even when this does not take place, we still feel a propensity to
confound these ideas, tho' we are not able fully to satisfy ourselves in
that particular, nor find any thing invariable and uninterrupted to jus-
tify our notion of identity.
Thus the controversy concerning identity is not merely a dispute
of words. For when we attribute identity, in an improper sense, to
variable or interrupted objects, our mistake is not confin'd to the ex-
pression, but is commonly attended with a fiction, either of something
invariable and uninterrupted, or of something mysterious and inex-
plicable, or at least with a propensity to such fictions. What will
suffice to prove this hypothesis to the satisfaction of every fair en-
quirer, is to shew from daily experience and observation, that the
objects, which are variable or interrupted, and yet are suppos'd to
continue the same, are such only as consist of a succession of parts,
connected together by resemblance, contiguity, or causation. For
as such a succession answers evidently to our notion of diversity,
it can only be by mistake we ascribe to it an identity; and as the
relation of parts, which leads us. into this mistake, is really nothing but
a quality, which produces an association of ideas, and an easy transition
of the imagination from one to another, it can only be from the resem-
blance, which this act of the mind bears to that, by which we contem-
plate one continu'd object, that the error arises. Our chief business,
then, must be to prove, that all objects, to which we ascribe identity,
without observing their invariableness and uninterruptedness, are such
as consist of a succession of related objects.
In order to this, suppose any mass of matter, of which the part\
are contiguous and connected, to be plac'd before us ; 'tis plain we must
attribute a perfect identity to this mass, provided all the parts continue
uninterruptedly and invariably the same, whatever motion or change
of place we may observe either in the whole or in any of the parts.
But supposing some very small or inconsiderable part to be added to
the mass, or substracted from it ; tho' this absolutely destroys the iden-
tity of the whole, strictly speaking ; yet as we seldom think so accurately v
we scruple not to pronounce a mass of matter the same, where we find
so trivial an alteration. The passage of the thought from the object
before the change to the object after it, is so smooth and easy, that we
EIGHTEENTH CENTURY PHILOSOPHY 193
scarce perceive the transition, and are apt to imagine that 'tis nothing
but a continu'd survey of the same object.
There is a very remarkable circumstance, that attends this experi-
ment ; which is, that tho' the change of any considerable part in a mass
of matter destroys the identity of the whole, yet we must measure the
greatness of the part, not absolutely, but by its proportion to the whole.
The addition or diminution of a mountain wou'd not be sufficient to
produce a diversity in a planet; tho' the change of a very few inches
wou'd be able to destroy the identity of some bodies. 'Twill be impos-
sible to account for this, but by reflecting that objects operate upon the
mind, and break or interrupt the continuity of its actions not according
to their real greatness, but according to their proportion to each other :
And therefore, since this interruption makes an object cease to appear
the same, it must be the uninterrupted progress of the thought, which
constitutes the [im] perfect identity.
This may be confirm'd by another phenomenon. A change in any
considerable part of a body destroys its identity; but 'tis remarkable,
that where the change is produc'd gradually and insensibly we are less
apt to ascribe to it the same effect. The reason can plainly be no other,
than that the mind, in following the successive changes of the body,
feels an easy passage from the surveying its condition in one moment
to the viewing of it in another, and at no particular time perceives any
interruption in its actions. From which continu'd perception, it ascribes
a continu'd existence and identity to the object.
But whatever precaution we may use in introducing the changes
gradually, and making them proportionable to the whole, 'tis certain,
that where the changes are at last observ'd to become considerable, we
make a scruple of ascribing identity to such different objects. There
is, however, another artifice, by which we may induce the imagination
to advance a step farther ; and that is, by producing a reference of the
parts to each other, and a combination to some common end or purpose.
A ship, of which a considerable part has been chang'd by frequent rep-
arations, is still consider'd as the same; nor does the difference of the
materials hinder us from ascribing an identity to it. The common end,
in which the parts conspire, is the same under all their variations, and
affords an easy transition of the imagination from one situation of the
body to another.
But this is still more remarkable, when we add a sympathy of parts
to their common end, and suppose that they bear to each other, the
194 EIGHTEENTH CENTURY PHILOSOPHY
reciprocal relation of cause and effect in all their actions and operations.
This is the case with all animals and vegetables ; where not only the sev-
eral parts have a reference to some general purpose, but also a mutual
dependence on, and connection with each other. The effect of so strong
a relation is, that tho' every one must allow, that in a very few years
both vegetables and animals endure a total change, yet we still attri-
bute identity to them, while their form, size, and substance are entirely
alter'd. An oak, that grows from a small plant to a large tree, is still
the same oak ; tho' there be not one particle of matter, or figure of its
parts the same. An infant becomes a man, and is sometimes fat, some-
times lean, without any change in his identity.
We may also consider the two following phenomena, which are
remarkable in their kind. The first is, that tho' we commonly be able
to distinguish pretty exactly betwixt numerical and specific identity,
yet it sometimes happens, that we confound them, and in our thinking
and reasoning employ the one for the other. Thus a man, who hears a
noise, that is frequently interrupted and renew'd, says, it is still the same
noise ; tho' 'tis evident the sounds have only a specific identity or resem-
blance, and there is nothing numerically the same, but the cause, which
produc'd them. In like manner it may be said without breach of the
propriety of language, that such a church, which was formerly of brick,
fell to ruin, and that the parish rebuilt the same church of free-stone,
and according to modern architecture. Here neither the form nor
materials are the same, nor is there any thing common to the two
objects, but their relation to the inhabitants of the parish; and yet this
alone is sufficient to make us denominate them the same. But we must
observe, that in these cases the first object is in a manner annihilated
before the second comes into existence ; by which means, we are never
presented in any one point of time with the idea of difference and multi-
plicity ; and for that reason are less scrupulous in calling them the same.
Secondly, We may remark, that tho' in a succession of related ob-
jects, it be in a manner requisite, that the change of parts be not sudden
nor entire, in order to preserve the identity, yet where the objects are
in their nature changeable and inconstant, we admit of a more sudden
transition, than wou'd otherwise be consistent with that relation. Thus
as the nature of a river consists in the motion and change of parts;
tho' in less than four and twenty hours these be totally alter'd; this
hinders not the river from continuing the same during several ages.
What is natural and essential to any thing is, in a manner, expected;
EIGHTEENTH CENTURY PHILOSOPHY 195
and what is expected makes less impression, and appears of less mo-
ment, than what is unusual and extraordinary. A considerable change
of the former kind seems really less to the imagination, than the most
trivial alteration of the latter ; and by breaking less the continuity of the
thought, has less influence in destroying the identity.
We now proceed to explain the nature of personal identity, which
has become so great a question in philosophy, especially of late years
in England, where all the abstruser sciences are study'd with a peculiar
ardour and application. And here 'tis evident, the same method of
reasoning must be continu'd, which has so successfully explain'd the
identity of plants, and animals, and ships, and houses, and of all the
compounded and changeable productions either of art or nature. The
identity, which we ascribe to the mind of man, is only a fictitious one,
and of a like kind with that which we ascribe to vegetables and animal
bodies. It cannot, therefore, have a different origin, but must proceed
from a like operation of the imagination upon like objects.
But lest this argument should not convince the reader ; tho' in my
opinion perfectly decisive ; let him weigh the following reasoning, which
is still closer and more immediate. Tis evident that the identity, which
we attribute to the human mind, however perfect we may imagine it to
be, is not able to run the several different perceptions into one, and make
them lose their characters of distinction and difference, which are essen-
tial to them. 'Tis still true, that every distinct perception, which enters
into the composition of the mind, is a distinct existence, and is different
and distinguishable, and separable from every other perception, either
contemporary or succesive. But, as, notwithstanding this distinction
and separably, we suppose the whole train of perceptions to be united
by identity, a question naturally arises concerning this relation of iden-
tity ; whether it be something that really binds our several perceptions
together, or only associates their ideas in the imagination. That is, in
other words, whether in pronouncing concerning the identity of a per-
son, we observe some real bond among his perceptions, or only feel
one among the ideas we form of them. This question we might easily
decide if we wou'd recollect what has been already prov'd at large, that
the understanding never observes any real connexion among objects,
and that even the union of cause and effect, when strictly examin'd,
resolves itself into a customary association of ideas. For from thence
it evidently follows, that identity is nothing really belonging to these
different perceptions and uniting them together ; but is merely a quality,
196 EIGHTEENTH CENTURY PHILOSOPHY
which we attribute to them, because of the union of their ideas in the
imagination, when we reflect upon them. Now the only qualities which
can give ideas an union in the imagination, are these three relations
above mentioned. These are the uniting principles in the ideal world,
and without them every distinct object is separable by the mind, and
may be separately considered, and appears not to have any more con-
nection with any other object than if disjoined by the greatest differ-
ence and remoteness. 'Tis, therefore, on some of these three relations
of resemblance, contiguity and causation that identity depends ; and as
the very essence of these relations consists in their producing an easy
transition of ideas; it follows, that our notions of personal identity
proceed entirely from the smooth and uninterrupted progress of the
thought along a train of connected ideas, according to the princples
above explained.
The only question, therefore, which remains, is, by what relations
this uninterrupted progress of our thought is produc'd when we con-
sider the successive existence of a mind or thinking person. And here
'tis evident we must confine ourselves to resemblance and causation, and
must drop contiguity, which has little or no influence in the present
case.
i
To begin with resemblance ; suppose we could see clearly into the
breast of another, and observe that succession of perceptions, which con-
stitutes his mind or thinking principle, and suppose that he always pre-
serves the memory of a considerable part of past perceptions ; 'tis evident
that nothing cou'd more contribute to the bestowing a relation on this
succession amidst all its variations. For what is the memory but a
faculty, by which we raise up the image? of past perceptions? And
as an image necessarily resembles its object, must not the frequent
placing of these resembling perceptions in the chain of thought, convey
the imagination more easily from one link to another and make the
whole seem like the continuance of one object? In this particular, then,
the memory not only discovers the identity, but also contributes to its
production, by producing the relation of resemblance among the per-
ceptions. The case is the same whether we consider ourselves or others.
As to causation ; we may observe that the true idea of the human
mind is to consider it as a system of different perceptions or different
existences, which are linked together by the relation of cause and effect,
and mutually produce, destroy, influence and modify each other. Our
impressions give rise to their correspondent ideas; and these ideas in
EIGHTEENTH CENTURY PHILOSOPHY 197
their turn produce other impressions. One thought chases another
and draws after it a third, by which it is expelled in its turn.
In this respect, I cannot compare the soul more properly to any thing
than to a republic or commonwealth in which the several members are
united by the reciprocal ties of government and subordination, and give
rise to other persons, who propagate the same republic in the incessant
changes of its parts. And as the same individual republic may not only
change its members, but also its laws and constitutions ; in like manner
the same person may vary his character and disposition, as well as his
impressions and ideas, without losing his identity. Whatever changes
he endures, his several parts are still connected by the relation of causa-
tion. And in this view our identity with regard to the passions serves
to corroborate that with regard to the imagination, by the making our
distant perceptions influence each other, and by giving us a present
concern for our past or future pains or pleasures.
As memory alone acquaints us with the continuance and extent of
this succession of perceptions, 'tis to be consider'd, upon that account
chiefly, as the source of personal identity. Had we no memory, we
never should have any notion of causation, nor consequently of that
chain of causes and effects, which constitute our self or person. But hav-
ing once acquir'd this notion of causation from the memory, we can ex-
tend the same chain of causes, and consequently the identity of our per-
sons beyond our memory, and can comprehend times, and circumstances,
and actions, which we have entirely forgot, but suppose in general to
have existed. For how few of our past actions are there of which we
have any memory? Who can tell me, for instance, what v/ere his
thoughts and actions on the first of January, 1715, the nth of March,
1719, and the 3d of August, 1733? Or will he affirm, because he has
entirely forgot the incidents of these days that the present self is not
the same person with the self of that time ; and by that means overturn
all the most establish'd notions of personal identity? In this view,
therefore, memory does not so much produce as discover personal iden-
tity, by shewing us the relation of cause and effect among our different
perceptions. 'Twill be incumbent on those, who affirm that memory
produces entirely our personal identity, to give a reason why we can
thus extend our identity beyond our memory.
The whole of this doctrine leads us to a conclusion, which is of
great importance in the present affair, vis. that all the nice and subtile
questions concerning personal identity can never possibly be decided,
198 EIGHTEENTH CENTURY PHILOSOPHY
and are to be regarded rather as grammatical than as philosophical
difficulties. Identity depends on the relations of ideas ; and these rela-
tions produce identity by means ojf that easy transition they occasion.
But as the relations and the easiness of the transition may diminish by
insensible degrees, we have no just standard by which we can decide
any dispute concerning the time when they acquire or lose a title to the
name of identity. All the disputes concerning the identity of connected
objects are merely verbal, except so far as the relation of parts gives
rise to some fiction or imaginary principle of union, as we have already
observed.
What I have said concerning the first origin and uncertainty of our
notion of identity, as applied to the human mind, may be extended with
little or no variation to that of simplicity. An object, whose different
co-existent parts are bound together by a close relation, operates upon
the imagination after much the same manner as one perfectly simple
and undivisible, and requires not a much greater stretch of thought in
order to its conception. From this similarity of operation we attribute
a simplicity to it, and feign a principle of union as the support of this
simplicity and the center of all the different parts and qualities of the
object.
Thus we have finished our examination of the several systems of
philosophy, both of the intellectual and moral world ; and in our mis-
cellaneous way of reasoning have been led into several topics; which
will either illustrate and confirm some preceding part of this discourse,
or prepare the way for our following opinions. Tis now time to re-
turn to a more close examination of our subject and to proceed in the
accurate anatomy of human nature, having fully explained the nature
of our judgment and understanding.
NOTE ON THE ABOVE
I had entertained some hopes, that however deficient our theory
of the intellectual world might be, it would be free from those contra-
dictions and absurdities which seem to attend every explication that
human reason can give of the material world. But upon a more strict
review of the section concerning personal identity I find myself in-
volved in such a labyrinth, that, I must confess, I neither know how to
correct my former opinions, nor how to render them consistent. If
this be not a good general reason for scepticism, 'tis at least a sufficient
one (if I were not already abundantly supplied) for me to entertain a
EIGHTEENTH CENTURY PHILOSOPHY 199
diffidence and modesty in all my decisions. I shall propose the argu-
ments on both sides, beginning with those that induced me to deny the
strict and proper identity and simplicity of a self or thinking being.
When we talk of self for substance, we must have an idea annexed
to these terms, otherwise they are altogether unintelligible. Every idea
is derived from preceding impressions ; and we have no impression of
self or substance, as something simple and individual. We have, there-
fore, no idea of them in that sense.
Whatever is distinct, is distinguishable; and whatever is distin-
guishable is separable by the thought or imagination. All perceptions
are distinct. They are, therefore, distinguishable and separable, and
may be conceived as separately existent, and may exist separately, with-
out any contradiction or absurdity.
When I view this table and that chimney, nothing is present to me
but particular perceptions, which are of a like nature with all the other
perceptions. This is the doctrine of philosophers. But this table, which
is present to me, and that chimney, may and do exist separately. This
is the doctrine of the vulgar, and implies no contradiction. There is no
contradiction, therefore, in extending the same doctrine to all the per-
ceptions.
In general the following reasoning seems satisfactory. All ideas are
borrow'd from preceding perceptions. Our ideas of objects, therefore,
are deriv'd from that source. Consequently no proposition can be intel-
ligible or consistent with regard to objects, which is not so with regard
to perceptions. But 'tis intelligible and consistent to say, that objects ex-
ist distinct and independent, without any common simple substance or
subject of inhesion. This proposition, therefore, can never be absurd
with regard to perceptions.
When I turn my reflection on myself, I never can perceive this self
without some one or more perceptions; nor can I ever perceive any
thing but the perceptions. 'Tis the composition of these, therefore,
which forms the self.
We can conceive a thinking being to have either many or few per-
ceptions. Suppose the mind to be reduc'd even below the life of an
oyster. Suppose it to have only one perception, as of thirst or hunger.
Consider it in that situation. Do you conceive any thing but merely that
perception? Have you any notion of self or substance? If not, the ad-
dition of other perceptions can never give you that notion.
The annihilation, which some people suppose to follow upon death,
200 EIGHTEENTH CENTURY PHILOSOPHY
and which entirely destroys this self, is nothing but an extinction of all
particular perceptions ; love and hatred, pain and pleasure, thought and
sensation. These therefore must be the same with self ; since the one
cannot survive the other.
Is self the same with substance? If it be, how can that question
have place, concerning the subsistence of self, under a change of sub-
stance ? If they be distinct, what is the difference betwixt them ? For
my part, I have a notion of neither, when conceiv'd distinct from par-
ticular perceptions.
Philosophers begin to be reconciled to the principle, that we have no
idea of external substance, distinct from the ideas of particular qualities.
This must pave the way for a like principle with regard to the mind,
that we have no notion of it, distinct from the particular perceptions.
So far I seem to be attended with sufficient evidence. But having
thus loosen'd all our particular perceptions, when I proceed to explain
the principle of connexion, which binds them together, and makes us at-
tribute to them a real simplicity and identity; I am sensible, that my
account is very defective, and that nothing but the seeming evidence of
the precedent reasonings cou'd have induc'd me to receive it. If percep-
tions are distinct existences, they form a whole only by being connected
together. But no connexions among distinct existences are ever discov-
erable by human understanding. We only feel a connexion or determi-
nation of the thought, to pass from one object to another. It follows,
therefore, that the thought alone finds personal identity. When
reflecting on the train of past perceptions that compose a mind the ideas
of them are felt to be connected together, and naturally introduce each
other. However extraordinary this conclusion may seem, it need not
surprize us. Most philosophers seem inclin'd to think, that personal
identity arises from consciousness ; and consciousness is nothing but a
reflected thought or perception. The present philosophy, therefore, has
so far a promising aspect. But all my hopes vanish, when I come to ex-
plain the principles, that unite our successive perceptions in our thought
or consciousness. I cannot discover any theory, which gives me satis-
faction on this head.
In short there are two principles, which I cannot render consistent ;
nor is it in my power to renounce either of them, viz. that all our
distinct perceptions are distinct existences, and that the mind never per-
ceives any real connexion among distinct existences. Did our percep-
tions either inhere in something simple and individual, or did the mind
EIGHTEENTH CENTURY PHILOSOPHY 201
perceive some real connexion among them, there woti'd be no difficulty in
the case. For my part, I must plead the privilege of a sceptic, and con-
fess that this difficulty is too hard for my understanding. I pretend not,
however, to pronounce it absolutely insuperable. Others, perhaps, or
myself, upon more mature reflections, may discover some hypothesis,
that will reconcile those contradictions.
KANT
IM MANUEL KANT was born at Koenigsberg, Prussia, April 2.2,
1724. His father was of Scottish descent. From 1740 to 1746 Kant
studied theology, and for the next nine years made his living as a tutor.
In 1755 he returned to the university at Koenigsberg, and after receiv-
ing his doctor's degree, acted as a privat docent until 1770, when he was
appointed Prof, of Logic and Metaphysics. He never married, al-
though of a social disposition, and never left his native city, unless in a
brief walk into the country. He died February 12, 1804.
In 1754 he noted the slight retardation of the earth's motion on
account of the tides. In the next year he suggested a nebular hypothesis
of the origin of the universe, thus really antedating Laplace. His most
important work is, however, the Critique of Pure Reason, published in
1781. The Critique of Practical Reason followed in 1788 and the
Critique of Judgment in 1790. The three form the starting point of our
philosophy to-day.
Kant saw that on the one hand the continental philosophy had devel-
oped into dogmatic speculation, and that on the other English philos-
ophy, starting from Locke's assumption that all knowledge comes from
experience, that is, from sensation and subsequent reflection, had devel-
oped into a scepticism that denied the possibility of anything more than
probable knowledge. Kant set himself to re-examine that basis of
knowledge and the elements of the mind. He wanted to account for the
possibility of mathematics and natural science, and to discover whether
metaphysics is possible at all. His solution of the problem is briefly
this : The matter of knowledge comes from experience, the form is fur-
nished by the active mind itself. Space, time, and the various relations,
V 6-13
202 EIGHTEENTH CENTURY PHILOSOPHY
such as substance and accident or cause and effect, are forms given to
our knowledge by the mind. They must apply to anything we can ex-
perience, but we cannot know whether they apply to things in them-
selves. Mathematics is possible because we analyze space and time,
which are mental ; physics is possible because all experience must be sub-
ject to cause and effect, the quantitative relations, and the like, all of
which are laws of the understanding. Reason's laws hold good for all
experience but they cannot be applied to things we cannot experience.
Things in themselves we do not know; we cannot indubitably demon-
strate the existence or nature of God or the angels. Though all experi-
ence rests on the unifying activity of the self or apperception, yet the
soul is outside of experience and these laws do not apply to it. Hence
the soul, and God, and things in their higher reality are left free and un-
confined by human law.
Kant died in 1804, but his thought is still the most important factor
in philosophy. Most of the steps taken since have had to be retraced,
and any future philosophy will be indebted to his analysis of the elements
of knowledge. This is no place to attempt a criticism of his system, but
we will take the liberty to suggest a few points for thought. If cause
and effect together with space, time, etc., is merely a mental form, not to
be applied at all outside of experience, has Kant the right to presuppose
things in themselves at all as a cause of our sensations, seeing that we
cannot directly experience them, but can argue their existence only thro'
the idea of cause and effect? If not, he would be forced into idealism.
On the other hand, the reasons are growing stronger for supposing that
there is a close correspondence, or rather concomitant variation, be-
tween our perceptions and nature. The more science discovers, the less
room there is left for freedom from the laws of experience in so-called
physical nature. As philosophy must account for the possibility of sci-
ence, and hence may use its results as data, we may ask whether on the
principle of evolution any race would have survived whose fundamental
mental life, .upon which it had to act in regard to its environment, was
entirely at variance with reality ? Would not the law of the survival of
the fittest eventually make such fundamental conceptions of the race as
time and space an index of reality? To sum up our question on this
point, isn't it possible for the various relations to be mental and at the
same time closely represent reality? But further discussion and the
philosophy since Kant's time must be reserved for another volume.
EIGHTEENTH CENTURY PHILOSOPHY 203
THE PROLEGOMENA
These Prolegomena are for the use, not of pupils, but of mature
teachers, and are intended to serve even the latter, not in arranging their
exposition of an existing science, but in discovering the science itself.
There are learned men, to whom the history of philosophy (both an-
cient and modern) is philosophy itself; for such the present Prolego-
mena are not written. They must wait till those who endeavour to draw
from the fountain of reason itself have made out their case ; it will then
be the historian's turn to inform the world of what has been done.
Moreover, nothing can be said, which in their opinion has not been said
already, and indeed this may be applied as an infallible prediction to all
futurity ; for as the human reason has for many centuries pursued with
ardour infinitely various (2) objects in various ways, it is hardly to be
expected that we should not be able to match every new thing with some
old thing not unlike it.
My object is to persuade all who think Metaphysic worth studying
that it is absolutely necessary to adjourn for the present this (historical)
labour, to consider all that has been done as undone, and to start first of
all with the question, 'Whether such a thing as metaphysic be at all pos-
sible?'
If it be a science, how comes it that it cannot, like other sciences, ob-
tain for itself an universal and permanent recognition ? If not, how is it
ever making constant pretensions, under this supposition, and keeping
the human mind in suspense with hopes that never fade, and yet are
nevur fulfilled ? Whether then, as a result, we demonstrate our knowl-
edge or our ignorance, we must come once for all to a definite conclu-
sion about the nature of this pretended science, which cannot possibly re-
main on its present footing. It seems almost ridiculous, while every
other science is continually advancing, that in this, which would be very
Wisdom, at whose oracle all men inquire, we should perpetually revolve
round the same point, without gaining a single step. And so its follow-
ers having melted away, we do not find men who feel able to shine in
other sciences venturing their reputation here, where everybody, how-
ever ignorant in other matters, pretends to deliver a final verdict, as in
this domain (3) there is as yet no certain weight and measure to dis-
tinguish sound knowledge from shallow talk.
204 EIGHTEENTH CENTURY PHILOSOPHY
But after long elaboration of a science, when men begin to wonder
how far it has advanced, it is not without precedent that the question
should at last occur, whether and how such a science be even possible?
For the human reason is so constructive, that it has already several times
built up a tower, and then razed it to examine the nature of the founda-
tion. It is never too late to mend ; but if the change comes late, there is
always more difficulty in setting it going.
The question whether a science be possible presupposes a doubt as
to its actuality. But such a doubt offends the men. whose whole posses-
sions consist of this supposed jewel ; hence he who raises the doubt must
expect opposition from all sides. Some, in the proud consciousness of
their possessions, which are ancient, and therefore considered legitimate,
will take their metaphysical compendia in their hands, and look down on
him with contempt ; others, who never sec anything except it be identical
with what they have seen before, will not understand him, and every-
thing will remain for a time, as if nothing had happened to excite the
concern, or the hope, for an impending change.
Nevertheless, I venture to predict that the independent reader of
these Prolegomena will not only doubt his previous science, but ulti-
mately be (4) fully persuaded, that it cannot exist without satisfying tne
demands here stated, on which its possibility depends ; and, as- this has
never been done,, that there is, as yet, no such thing as Metaphysic. But
as it can never cease to be in demand —
'Rusticus expectat, dum defluat amnis, at ille
Labitur et labetur in omne volubilis aevum ;' —
since the interests of mankind are interwoven with it so intimately, he
must confess that a radical reform, or rather a new birth of the science
after an original plan, must be unavoidably at hand, however men may
struggle against it for a while.
Since the Essays of Locke and Leibnitz, or rather since the origin of
metaphysic so far as we know its history, nothing has ever happened
which might have been more decisive to the fortunes of the science than
the attack made upon it by David Hume. He threw no light on this spe-
cies of knowledge, but he certainly struck a spark from which light
might have been obtained, had it caught a proper substance to nurture
and develop the flame.
Hume started chiefly from a single but important concept in Meta-
physic— that of Cause and Effect (including the deduced notions of
action and power). He calls on reason, which pretends to have gener-
EIGHTEENTH CENTURY PHILOSOPHY 205
ated this notion from itself, to answer him with what right it thinks
anything to be so constituted, that if granted, something else must neces-
sarily be [5] granted thereby; for this is the meaning of the concept of
cause. He demonstrated irresistibly that it was perfectly impossible for
reason to think such a combination by means of concepts and a priori —
a combination that contains necessity. We cannot at all see why, in con-
sequence of the existence of one thing, another must necessarily exist, or
how the concept of such a combination can arise a priori. Hence he in-
ferred, that reason was altogether deluded by this concept, which it con-
sidered erroneously as one of its children, whereas in reality the concept
was nothing but the bastard offspring of the imagination, impregnated
by experience, and so bringing certain representations under the Law of
Association. The subjective necessity, that is, the custom which so
arises, is then substituted for an objective necessity from real knowl-
edge. Hence he inferred that the reason had no power to think such
combinations, even generally, because its concepts would then be mere
inventions, and all its pretended a priori cognitions nothing but com-
mon experiences marked with a false stamp. In plain language there is
not, and cannot be, any such thing as metaphysic at all. This conclu-
sion, however [6] hasty and mistaken, was at least founded upon inves-
tigation, and the investigation deserved to have suggested to the brighter
spirits of his day a combined attempt at a happy solution of the prob-
lem proposed by him, if such solution were possible. Thus a complete
reform of the science must have resulted.
But the perpetual hard fate of metaphysic would not allow him to be
understood. We cannot without a certain sense of pain consider how
utterly his opponents, Reid, Oswald, Beattie, and even Priestley, missed
the point of the problem. For while they were ever assuming as con-
ceded what he doubted, and demonstrating with eagerness and often
with arrogance wrhat he never thought of disputing, they so overlooked
his indication toward a better state of things, that everything remained
undisturbed in its old condition.
The question was not whether the concept of cause was right, use-
ful, and even indispensable with regard to our knowledge of nature, for
this Hume [7] had never doubted. But the question to which Hume ex-
pected an answer was this, whether that concept could be thought by the
reason a priori, and whether it consequently possessed an inner truth, in-
dependent of all experience, and therefore applied more widely than to
the mere objects of experience. It was surely a question concerning the
203 EIGHTEENTH CENTURY PHILOSOPHY
origin, not concerning the indispensable use of the concept. Had the
former question been determined, the conditions of the use and valid ap-
plication of the concept would have been given ipso facto.
But the opponents of the great thinker should have probed very
deeply into the nature of the reason, so far as it concerns pure think-
ing, if they would satisfy the conditions of the problem—a task which did
not suit them. They therefore discovered a more convenient means of
putting on a bold face without any proper insight into the question, by
appealing to the common sense of mankind. It is indeed a great gift of
God, to possess right, or (as they now call it) plain common sense. But
this common sense must be shown practically, by well-considered and
reasonable thoughts and words, not by appealing to it as an oracle,
when you can advance nothing rational in justification of yourself. To
appeal to common sense, when insight and science fail, and no sooner —
this is one of the subtle discoveries of modern times, by means of which
the most vapid babbler can safely enter the lists with the most thor-
ough-[8] going thinker, and hold his own. But as long as a particle of
insight remains, no one would think of having recourse to this subter-
fuge. For what is it, but an appeal to the opinion of the multitude, of
whose applause the philosopher is ashamed, while the popular and super-
ficial man glories and confides in it ? I should think Hume might fairly
have laid as much claim to sound sense as Beattie, and besides to a criti-
cal understanding (such as the latter did not possess), which keeps com-
mon sense within such limits as to prevent it from speculating, or if it
does speculate, keeps it from wishing to decide when it cannot satisfy
itself concerning its own principles. By this means alone can common
sense remain sound sense. Chisels and hammers may suffice to work a
piece of wood, but for steel-engraving we require a special instrument.
Thus common sense and speculative understanding are each serviceable
in their own way, the former in judgments which apply immediately to
experience, the latter when we judge universally from mere concepts, as
in metaphysic, where that which calls itself (often per antiphrasin)
sound common sense has no right to judge at all.
I honestly confess, the suggestion of David Hume was the very
thing which many years ago first interrupted my dogmatic slumber, and
gave my investigations in the field of speculative philosophy quite a new
direction. I was far from following him [9] in all his conclusions, which
only resulted from his regarding not the whole of his problem, but a
part, which by itself can give us no information. If we start from a
EIGHTEENTH CENTURY PHILOSOPHY 207
well-founded, but undeveloped, thought, which another has bequeathed
to us, we may well hope by continued reflection to advance farther than
the acute man, to whom we owe the first spark of light.
I therefore first tried whether Hume's objection could not be put
into a general form, and soon found that the concept of the connexion of
cause and effect was by no means the only one by which the understand-
ing thinks the connexion of things a priori, but rather that metaphysic
consists altogether of such connexions. I sought to make certain of their
number, and when I had succeeded in this to my expectation, by start-
ing from a single principle, I proceeded to the deduction of these con-
cepts, which I was now certain were not deduced from experience, as
Hume had apprehended, but sprang from the pure understanding. This
deduction, which seemed impossible to my acute predecessor, which had
never even occurred to any one else, though they were all using the con-
cepts unsuspiciously without questioning the basis of their objective va-
lidity— this deduction was the most difficult task ever undertaken in aid
of metaphysic. More especially, no existing metaphysics could assist
me in the least, because this deduction must prove the [10] very possi-
bility of metaphysic. But as soon as I had succeeded in solving Hume's
problem not merely in a particular case, but with respect to the whole
faculty of pure reason, I could proceed safely, though slowly, to deter-
mine the whole sphere of pure reason completely and from general prin-
ciples, in its bounds, as well as in its contents. This was what metaphysic
required, in order to construct its system safely.
THE CRITIQUE OF PURE REASON
THE PROBLEM OF THE CRITIQUE
It is of very great advantage, to others, as well as to oneself, to be
able to bring together various topics of investigation in a single prob-
lem. Now, the true problem of pure reason may be put in this way —
How are a priori synthetic judgments possible?
Should this question be answered in a satisfactory way, we shall at
the same time learn what part reason plays in the foundation and com-
pletion of those sciences which contain a theoretical a priori knowledge
of objects. Thus we shall be able to answer the questions — How is pure
mathematics possible? How is pure physics possible? As these sci-
ences actually exist, we may fairly ask how they are possible; for that
203 EIGHTEENTH CENTURY PHILOSOPHY
they must be possible is proved by the fact that they exist. Bat as no
real progress has as yet been made in the construction of a system that
realizes the essential aim of metaphysic, it cannot be said that metaphysic
exists, and there is, therefore, reason to doubt whether it is possible
at all.
Yet in one sense metaphysic may certainly be said to exist, namely,
in the sense that there is in man a natural disposition to seek for this kind
of knowledge. But as all attempts to answer the questions which human
reason is naturally impelled to ask, as, for instance, whether the world
had a beginning, or has existed from all eternity, have always and un-
avoidably ended in self-contradiction; we cannot be satisfied with as-
serting the mere natural disposition to metaphysical speculation, or, in
other words, with the bare ability of pure reason to construct some sort
of metaphysic. It must be possible for reason to attain to certainty one
way or the other : we must be able to ascertain whether reason can know
the objects it seeks, or whether it cannot know them; we must find a
conclusive answer to the question whether pure reason is capable or in-
capable of determining the nature of those objects, and whether, there-
fore, its domain may with confidence be enlarged beyond the limits of
experience, or must be restricted within them. Accordingly, the third
and last question, which flows from the general problem of pure reason,
may be correctly put in this way : How is a science of metaphysic pos-
sible? Thus a criticism of reason in the end necessarily leads to sci-
ence, whereas the dogmatic employment of reason without previous
criticism can lead only to groundless assertions, to which other assertions
equally specious may always be opposed, the inevitable result being
scepticism.
From all that has been said we get the idea of a unique science, which
may be called the Critique of Pure Reason. It is not a doctrine, but a
criticism of pure reason, and its speculative value is entirely negative,
because it does not enlarge our knowledge, but only casts light upon the
nature of our reason and enables us to keep it free from error. By
transcendental knowledge I mean all knowledge that is occupied, not
with objects, but with the way in which a knowledge of objects may be
gained, so far as that is possible a priori. What we propose is not a
doctrine of pure reason, but a transcendental criticism, the purpose of
which is not to extend knowledge, but to rectify it, and to supply a
touchstone of the value of all a priori knowledge.
This transcendental criticism will afford a complete architectonic
209
plan of transcendental philosophy, as exhibited in its principles, and will
therefore give a perfect guarantee of the completeness and stability of
die edifice in all its parts.
The Critique of Pure Reason therefore contains all that is essential
to the idea of transcendental philosophy, and if we distinguish it from
that philosophy, the reason is that it does not carry its analysis beyond
what is required in a complete estimate of a priori synthetic knowledge.
The main thing to be kept in view m the division of such a science is
that no ideas be allowed to enter that are in any way of empirical origin,
or, in other words, that it consist only of perfectly pure a priori know-
ledge. Hence, although the principles and fundamental conceptions of
morality are a priori, they form no part of a transcendental philosophy,
because they are necessarily relative to the conceptions of pleasure and
pain, desire and inclination, etc., which in their origin are empirical.
In a systematic division of this science we must have, firstly, a doc-
trine of the elements ; secondly, a doctrine of the method of pure reason.
As to the subdivisions, it seems enough to say at present that there are
two stems of human knowledge — Sensibility and Understanding, which
may perhaps spring from a common root, unknown to us, and that by
the one objects are given, by the other they are thought. Now, if Sen-
sibility is found to contain an a priori element, without which objects
could not be given to us, an investigation into the nature of that element
will be one of the tasks of transcendental philosophy. The doctrine of
this transcendental element of sensible perception will form the first part
of the science of elements, because we must consider the conditions un-
der which objects of human knowledge are given, before we go on
to inquire into the conditions under which they are thought.
TRANSLATION OF MAHAFFY AND BERNARD.
TRANSCENDENTAL AESTHETIC
Sensation is the actual affection of our sensibility, or capacity of re-
ceiving impressions, by an object. The perception which refers to an
object through sensation, is empirical perception. The undetermined
object of such a perception is a phenomenon ( Erscheinung) .
That element in the phenomenon which corresponds to sensation I
call the matter, while that element which makes it possible that the vari-
ous determinations of the phenomenon should be arranged in certain
ways relatively to one another, is its form. Now, sensations cannot pos-
sibly give order or form to themselves. The matter of a phenomenon is
given to us entirely a posteriori, but its form must lie a priori in the
210 EIGHTEENTH CENTURY PHILOSOPHY
mind, ready to be applied to all sensations as they arise, and hence it
must be capable of being considered by itself apart from sensation.
This pure form of sensibility is also called pure perception. Thus,
if from the consciousness of a body, I separate all that the understanding
has thought into it, as substance, force, divisibility, etc., and all that
is due to sensation, as impenetrability, hardness, colour, etc. ; what is left
over are extension and figure. These, therefore, belong to pure percep-
tion, which exists in the mind a priori, as a mere form of sensibility,
even when no sensation or object of sense is actually present.
The science of all the a priori principles of sensibility I call Trans-
cendental ^Esthetic, in contradistinction from the science of the princi-
ples of pure thought, which I call Transcendental Logic.
In Transcendental ^Esthetic we shall first of all isolate sensibility,
abstracting from all that the understanding contributes through its con-
ceptions, so that we may have nothing before us but empirical percep-
tion. In the next place, we shall separate from empirical perception all
that belongs to sensation ; when there will remain only pure perception,
or the mere form of phenomena, the sole element that sensibility can
yield a priori. If this is done, it will be found that there are two pure
forms of sensible perception, which constitute principles of a priori
knowledge, namely, Space and Time. With these it will now be our
business to deal.
SECTION I. SPACE
B. Metaphysical Exposition of Space.
In external sense we are conscious of objects as outside of ourselves,
and as all without exception in space. In space their shape, size, and
relative position are marked out, or are capable of being marked out.
Inner sense, in which we are conscious of ourselves, or rather of our own
state, gives us, it is true, no direct perception of the soul itself as an ob-
ject; but it nevertheless is the one single form in which our own state
comes before us as a definite object of perception; and hence all inner
determinations appear to us as related to one another in time. We can-
not be conscious of time as external, any more than we can be conscious
of space as something within us. What then, are space and time ? Are
they in themselves real things? Are they only determinations, or per-
haps merely relations of things which yet would belong to things in
themselves even if those things were not perceived by us ? Or, finally,
have space and time no meaning except as forms of perception, belong-
EIGHTEENTH CENTURY PHILOSOPHY 211
ing to the subjective constitution of our own mind, apart from which
they cannot be predicated of anything whatever ? To answer these ques-
tions I shall begin with a metaphysical exposition of space. An exposi-
tion I call it, because it gives a distinct although not a detailed, statement
of what is implied in the idea of space ; and the exposition is metaphysi-
cal, because it brings forward the reasons we have for regarding space
as given a priori.
(1) Space is not an empirical conception, which has been derived
from external experiences. For I could not be conscious that certain of
my sensations are relative to something outside of me, that is, to some-
thing in a different part of space from that in which I myself am ; nor
could I be conscious of them as outside of and beside one another, were I
not at the same time conscious that they not only are different in con-
tent, but are in different places. The consciousness of space is, there-
fore, necessarily presupposed in external perception. No experience of
the external relations of sensible things could yield the idea of space, be-
cause without the consciousness of space there would be no external
experience whatever.
(2) Space is a necessary a priori idea, which is presupposed in all
external perceptions. By no effort can we think space to be away, al-
though we can quite readily think of space as empty of objects. Space
we therefore regard as a condition of the possibility of phenomena and
not as a determination dependent on phenomena. It is thus a priori, and
is necessarily presupposed in external phenomena.
(3) Space is not a discursive or general conception of the relations
of things, but a pure perception. For we can be conscious only of a sin-
gle space. It is true that we speak as if there were many spaces, but we
really mean only parts of one and the same identical space. Nor can we
say that these parts exist before the one all-embracing space, and are put
together to form a whole ; but we can think of them only as in it. Space
is essentially single ; by the plurality of spaces we merely mean that be-
cause space can be limited in many ways, the general conception of
spaces presupposes such limitations as its foundation. From this it
follows, that an a priori perception, and not an empirical perception, un-
derlies all conceptions of pure space. Accordingly, no geometrical prop-
osition, as, for instance, that any two sides of a triangle are greater than
the third side, can ever be derived from the general conceptions of line
and triangle, but only from perception. From the perception, however,
it can be derived a priori, and with demonstrative certainty.
912
(4) Space is presented before our consciousness as an infinite mag-
nitude. Now, in every conception we certainly think of a certain attri-
bute as .common to an infinite number of possible objects, which are
subsumed under the conception ; but, from its very nature, no conception
can possibly be supposed to contain an infinite number of determina-
tions within it. But it is just in this way that space is thought of, all its
parts being conceived to exist ad infinitum. Hence the original con-
sciousness of space is an a priori perception, not a conception,
c. Transcendental Exposition of Space
A transcendental exposition seeks to show how, from a certain prin-
ciple, the possibility of other a priori synthetic knowledge may be
explained. To be successful, it must prove ( i ) that there really are syn-
thetic propositions which can be derived from the principle in question,
(2) that they can be so derived only if a certain explanation of that prin-
ciple is adopted.
Now, geometry is a science that determines the properties of space
synthetically and yet a priori. What, then, must be the nature of space,
in order that such knowledge of it may be possible ? Our original con-
sciousness of it must be perception, for no new truth, such as we have in
the propositions of geometry, can be obtained from the mere analysis of
a given conception (Introduction, 5). And this perception must be
a priori, or, in other words, must be found in us before we actually ob-
serve an object, and hence it must be pure, not empirical perception.
For all geometrical propositions, as, for instance, that space has but
three dimensions, are of demonstrative certainty, or present themselves
in consciousness as necessary ; and such propositions cannot be empiri-
cal, nor can they be derived from judgments of experience (Introduc-
tion, 2).
How, then, can there be in the mind an external perception, which is
antecedent to objects themselves, and in which the conception of those
objects may be determined a priori? Manifestly, only if that percep-
tion has its seat in the subject, that is, if it belongs to the formal consti-
tution of the subject, in virtue of which it is so affected by objects as to
have a direct consciousness or perception of them ; therefore, only if
perception is the universal form of outer sense.
Our explanation is, therefore, the only one that makes the possibility
of geometry intelligible, as a mode of a priori synthetic knowledge. All
other explanations fail to do so, and, although they may have an ex-
EIGHTEENTH CENTURY PHILOSOPHY 213
ternal resemblance to oursr may readily be distinguished from it by this
criterion.
Inferences
(a) Space is in no sense a property of things in themselves, nor is it
a relation of things in themselves to one another. It is not a determina-
tion that still belongs to objects even when abstraction has been made
from all the subjective conditions of perception. For we never could
perceive a priori any determination of things, whether belonging to them
individually or in relation to one another, antecedently to our perception
of those things themselves.
(6) Space is nothing but the form of all the phenomena of outer
sense. It is the subjective condition without which no external percep-
tion is possible for us. The receptivity of the subject, or its capability
of being affected by objects, necessarily exists before there is any percep-
tion of objects. Hence it is easy to understand, how the form of all
phenomena may exist in the mind a priori, antecedently to actual ob-
servation, and how, as a pure perception in which all objects must be de-
termined, it may contain the principles that determine beforehand the
relations of objects when they are met with in experience.
It is, therefore, purely from our human point of view that we
speak of space, of extended things, etc. Suppose the objective conditions
to be taken away, without which we cannot have any external percep-
tion, or be affected by objects, and the idea of space ceases to have any
meaning. We cannot predicate spatial dimensions of things, except in so
far as they appear in our consciousness. The unalterable form of this re-
ceptivity, which we call sensibility, is a necessary condition of all the re-
lations in which objects are perceived as outside of us, and this form,
when it is viewed in abstraction from objects, is the pure perception that
is known by the name of space. We are not entitled to regard the con-
ditions that are proper to our sensibility as conditions of the possibility
of things, but only of things as they appear to us. Hence, while it is
correct to say, that space embraces all things that are capable of appear-
ing to us as external, we cannot say, that it embraces all things as they
are in themselves, no matter what subject may perceive them, and, in-
deed, whether they are perceived or not. For we have no means of
judging whether other thinking beings are in their perceptions bound
down by the same conditions as ourselves, and which for us hold uni-
versally. If we state the limitations under which a judgment holds
of a given subject, the judgment is then unconditionally true. The
214 EIGHTEENTH CENTURY PHILOSOPHY
proposition that all things are side by side in space, is true only under
the limitation that we are speaking of our own sensible perception.
But if we more exactly define the subject of the proposition by saying,
that all things as external phenomena are side by side in space, it
will be true universally and without any exception. Our exposition,
therefore, establishes the reality, or objective truth of space as a deter-
mination of every object that can possibly come before us as ex-
ternal; but at the same time it proves the ideality of space, when
space is considered by reason relatively to things in themselves, that
is, without regard to the constitution of our sensibility. We, there-
fore, affirm the empirical reality of space, as regards all possible ex-
ternal experience ; but we also maintain its transcendental ideality,' or,
in other words, we hold that space is nothing at all, if its limitation to
possible experience is ignored, and it is treated as a necessary condition
of things in themselves.
SECTION II. TIME
D. Metaphysical Exposition of Time
(1) Time is not an empirical conception, which has been derived
from any experience. For we should not observe things to co-exist or
to follow one another, did we not possess the idea of time a priori. It
is, therefore, only under the presupposition of time, that we can be con-
scious of certain things as existing at the same time (simultaneously),
or at different times (successively).
(2) Time is a necessary idea, which is presupposed in all percep-
tions. We cannot be conscious of phenomena if time is taken away, al-
though we can quite readily suppose phenomena to be absent from time.
Time is, therefore, given a priori. No phenomenon can exist at all that
is not in time. While, therefore, phenomena may be supposed to vanish
completely out of time, time itself, as the universal condition of their
possibility, cannot be supposed away.
(3) Time is not a discursive, or general conception, but a pure form
of sensible perception. Different times are but parts of the very same
time. Now, the consciousness of that which is presented as one single
object, is perception. Moreover, the proposition, that no two moments
of time can co-exist, cannot be derived from a general conception. The
proposition is synthetic, and cannot originate in mere conceptions. It
therefore rests upon the direct perception and idea of time.
(4) The infinity of time simply means, that every definite quantity
EIGHTEENTH CENTURY PHILOSOPHY 215
of time is possible only as a limitation of one single time. There must,
therefore, be originally a consciousness of time as unlimited. Now, if
an object presents itself as a whole, so that its parts and every quantity
of it can be represented only by limiting that whole, such an object can-
not be given in conception, for conceptions contain only partial deter-
minations of a thing. A direct perception must therefore be the
foundation of the idea of time.
E. Transcendental Exposition of Time
Apodictic principles which determine relations in time, or axioms of
time in general, are possible only because time is the necessary a priori
condition of all phenomena. Time has but one dimension; different
times do not co-exist but follow one another, just as different spaces do
not follow one another but co-exist. Such propositions cannot be de-
rived from experience, which never yields strict universality or demon-
trative certainty. If they were based upon experience, we could say
only, that it has ordinarily been observed to be so, not that it must be so.
Principles like these have the force of rules, that lay down the condi-
tions without which no experience whatever is possible; they are not
learned from experience, but anticipate what experience must be.
Let me add here that change, including motion or change of place, is
conceivable only in and through the idea of time. Were time not an in-
ner a priori perception, we could not form the least idea how there
should be any such thing as change. Take away time, and change com-
bines in itself absolutely contradictory predicates. Motion, or change
of place, for instance, must then be thought of as at once the existence
and the non-existence of one and the same thing in the same place. The
contradiction disappears, only when it is seen that the thing has those
opposite determinations one after the other. One conception of time as
an a priori form of perception, therefore explains the possibility of the
whole body of a priori synthetic propositions in regard to motion that
are contained in the pure part of physics, and hence it is not a little
fruitful in results.
F. Inferences
(a) Time is not an independent substance nor an objective deter-
mination of things, and hence it does not survive when abstraction has
been made from all the subjective conditions of perception. Were it an
independent thing, it would be real without being a real object of con-
sciousness. Were it a determination or order of things as they are in
themselves, it could not precede our perception of those things as its
216 EIGHTEENTH CENTURY PHILOSOPHY
necessary condition, nor could it be known by means of synthetc judg-
ments. But the possibility of such judgments becomes at once intelli-
gible if time is nothing but the subjective condition, without which we
can have no perception whatever. For in that case we may be conscious
of this form of inner perception before we are conscious of objects, and
therefore a priori.
(&) Time is nothing but the form of inner sense, that is, of the per-
ception of ourselves and our own inner state. As it has no influence on
the shape or position of an object, time cannot be a determination of
outer phenomena as such ; what it does determine is the relation of ideas
in our own inner state. And just because this inner perception has no
shape of its own, we seek to make up for this want by analogies drawn
from space. Thus, we figure the series of time as a line that proceeds
to infinity, the parts of which form a series ; and we reason from the
properties of this line to all the properties of time, taking care to allow
for the one point of difference, that the parts of the spatial line all exist
at once, while the parts of the temporal line all follow one after the
other. Even from this fact alone, that all the relations of time may thus
be presented in an external perception, it would be evident that time is
itself a perception.
(c) Time is the formal a priori condition of all phenomena without
exception. Space, as the pure form of all external phenomena, is the
a priori condition only of external phenomena. But all objects of per-
ception, external as well as internal, are determinations of the mind,
and, from that point of view, belong to our inner state. And as this
inner state comes under time, which is the formal condition of inner per-
ception, time is an a priori condition of all phenomena : it is the imme-
diate condition of inner phenomena, and so the mediate condition of
outer phenomena. Just as I can say, a priori, that all external phenom-
ena are in space, and are determined a priori in conformity with the re-
lations of space, so, from the principle of the inner sense, I can say quite
generally that all phenomena are in time, and stand necessarily in rela-
tions of time.
If we abstract from the manner in which we immediately perceive
our own inner state, and mediately all external phenomena, and think of
objects in themselves, we find that in relation to them time is nothing at
all. It is objectively true in relation to phenomena, because we are con-
scious of phenomena as objects of our senses ; but it is no longer ob-
jective, if we abstract from our sensibility, and therefore from the
EIGHTEENTH CENTURY PHILOSOPHY 217
form proper to our perceptive consciousness, and speak of things as
such. Time is therefore a purely subjective condition of human per-
ception, and in itself, or apart from the subject, it is nothing at all.
Nevertheless, it is necessarily objective in relation to all phenomena,
and therefore also to everything that can possibly enter into our experi-
ence. We cannot say that all things are in time, because when we
speak of things in this unqualified way, we are thinking of things in ab-
straction from the manner in which we perceive them, and therefore in
abstraction from the condition under which alone we can say that they
are in time. But, if we qualify our assertion by adding that condition,
and say that all things as phenomena, or objects of sensible perception,
are in time, the proposition is, in the strictest sense of the word, ob-
jective, and is universally true a priori.
We see, then, that time is empirically real, or is objectively true in
relation to all objects that are capable of being presented to our senses.
And as our perception always is sensuous, no object can ever be pre-
sented to us in experience which does net conform to time as its condi-
tion. On the other hand, we deny to time all claim to absolute reality,
because such a claim, in paying no heed to the form of sensible percep-
tion, assumes time to be an absolute condition or property of things.
Such properties, as supposed to belong to things in themselves, can
never be presented to us in sense. From this we infer the transcend-
ental ideality of time ; by which we mean that, in abstraction from the
subjective conditions of sensible perception, time is simply nothing, and
cannot be said either to subsist by itself, or to inhere in things that do
subsist.
G. Explanatory Remarks
To this doctrine, which admits the empirical reality of time, but
denies its absolute or transcendental reality, there is one objection so
commonly made, that I must suppose it to occur spontaneously to every-
body who is new to the present line of thought. It runs thus : No one
can doubt that there are real changes, for, even if it is denied that we
perceive the external world, together with the changes in it, we are at
least conscious of a change in our own ideas. Now, changes can take
place only in time. Therefore time is real.
There is no difficulty in meeting this objection. I admit all that is
said. Certainly time is real ; it is the real form of inner perception. It
has reality for me relatively to my inner experience ; in other words, I
actually am conscious of time and of my own determinations as in it
V 6-U
218 EIGHTEENTH CENTURY PHILOSOPHY
Time is therefore real, not as an object beyond consciousness, but as the
manner in which I exist for myself as an object of consciousness. But,
if I could be perceived by myself or by any other being without the con-
dition of sensibility, the very same determinations, which now appear as
changes, would not be known as in time, and therefore would not be
known as changes. The empirical reality of time thus remains, on our
theory, the condition of all our experience. It is only its absolute real-
ity that we refuse to admit. Time is therefore nothing but the form of
our inner perception. If we take away from it the peculiar condition of
our sensibility, the idea of time also vanishes ; for time does not belong
to objects as they are in themselves, but only to the subject that per-
ceives them.
Time and space are two sources of knowledge from which a variety
of a priori synthetic judgments may be derived. Mathematics, especi-
ally, supplies a splendid instance of such judgments, in the science of
space and the relations of space. Time and space are the two pure
forms of all sensible perception, and as such they make a priori syn-
thetic propositions possible. And just because they are mere conditions
of sensibility, they mark out their own limits as sources of a priori
knowledge. Applying only to objects regarded as phenomena, they do
not present things as they are in themselves. Beyond the phenomenal
world, which is their legitimate domain, they cannot be employed in de-
termination of objects. But this limitation in no way lessens the sta-
bility of our empirical knowledge; for, such knowledge, as depending
upon necessary forms of the perceptions of things, is just as certain as if
it rested upon necessary forms of things in themselves.
Transcendental Esthetic cannot contain more than these two ele-
ments. This is plain, if we reflect that all other conceptions belonging
to sensibility presuppose something empirical. Even the idea of mo-
tion, in which both elements are united, presupposes the observation of
something that moves. Now, there is nothing movable in space consid-
ered purely by itself ; hence that which is movable can be found in space
only by experience, and is therefore an empirical datum. Similarly the
idea of change cannot be put among the a priori data of transcendental
aesthetic. Time itself does not change, but only something that is in
time ; hence the idea of change must be derived from the observation of
some actual object with its successive determinations — that is, from
experience.
EIGHTEENTH CENTURY PHILOSOPHY 219
H. General Remarks on the Transcendental ^Esthetic
1 I ) A distinction is commonly drawn between what belongs essen-
tially to an object, and is perceived by every one to belong to it, and what
is accidental, being perceived only from a certain position, or when a
special organ is affected in a particular way. In the one case, we are
said to know the object as it is in itself; in the other case, to know it
only as it appears to us. This, however, is merely an empirical distinc-
tion. For, it must be remembered, that the empirical object which is
here called the thing, is itself but an appearance. If this were all, our
transcendental distinction would be altogether lost sight of, and we
might imagine ourselves to know things in themselves when we knew
only phenomena. For the truth is, that, however far we may carry our
investigations into the world of sense, we never can come into contact
with aught but appearances. For instance, we call the rainbow in a
sun-shower a mere appearance, and the rain the thing itself. Nor is
there any objection to this, if we mean to state merely the physical truth,
that from whatever position it is viewed the rain will appear to our
senses as a real object of experience. But, if we go beyond the fact,
that the sensible object is here the same for every one, and ask whether
the object is known as it is in itself, we pass to the transcendental point
of view, and the question now is in regard to the relation of our con-
sciousness of the object to the object as it exists apart from our con-
sciousness. In this point of view, not merely the rain-drops, but their
round shape, and even the space in which they fall, must be regarded as
mere appearances, not as things in themselves. Every aspect of the
phenomenon, in short, is but a modification or a permanent form of our
sensible perception, while the transcendental object remains to us un-
known.
(2) It is recognized in natural theology, not only that God cannot
be an object of perception to us, but that He can never be an object of
sensuous perception to Himself. At the same time, His knowledge
must be perception, and not thought, for thought always involves lim-
itations. Now, the natural theologian is very careful to say, that God,
in His perception, is free from the limits of space and time. But, how
can this possibly be maintained, if it has previously been assumed, that
space and time are forms of things in themselves ? It must then be held
that, even if those things were annihilated, space and time would con-
tinue to be a priori conditions of their existence. And if they are con-
ditions of all existence, they must be conditions of the existence even of
220 EIGHTEENTH CENTURY PHILOSOPHY
God. We can avoid this conclusion only by saying that space and time
are not objective forms of all things, but subjective forms of our outer
as well as of our inner perceptions. In fact our perception is sensuous,
just because it is not original. Were it original, the very existence of
the object would be given in the perception, and such a perception, so
far as we can see, can belong only to the Original Being. Our percep-
tion is dependent upon the existence of the object, and therefore it is
possible only if our perceptive consciousness is affected by the presence
of the object.
Nor is it necessary to say, that man is the only being who perceives
objects under the forms of space and time ; it may be that all finite think-
ing beings agree with man in that respect, although of this we cannot
be certain. But, however universal this mode of perception may be, it
cannot be other than sensuous, simply because it is derivative (intuitus
derivativus} and not original (intuitus originarius), and therefore is
not an intellectual perception. An intellectual perception, as we have
already seen reason to believe, is the prerogative of the Original Being,
and never can belong to a being which is dependent in its existence as
well as in its perception, and in fact is conscious of its own existence
only in relation to given objects.
Conclusion of the Transcendental JEsthetic
We have then, in the Transcendental Esthetic, one of the elements
required in the solution of the general problem of transcendental philos-
ophy : How are a priori synthetic propositions possible ? Such proposi-
tions rest upon space and time, which are pure a priori perceptions. To
enable us to go beyond a given conception, in an a priori judgment, we
have found that something is needed, which is not contained in the con-
ception, but in the perception corresponding to it, something therefore
that may be connected with that conception synthetically. But such
judgments, as based upon perception, can never extend beyond objects
of sense, and therefore hold true only for objects of possible experience.
TRANSCENDENTAL LOGIC
i. General Logic
There are two ultimate sources from which knowledge comes to .us :
either we receive ideas in the form of impressions, or, by our spontane-
ous faculty of conception, we know an object by means of those ideas.
In the former case, the object is given to us; in the latter case, it is
thought in relation to the impressions that arise in our consciousness.
EIGHTEENTH CENTURY PHILOSOPHY 221
Perception and conception, therefore, are the two elements that enter
into all our knowledge. To every conception some form of perception
corresponds, and no perception yields knowledge without conception.
Both may be either pure or empirical ; empirical, if sensation, which
occurs only in the actual presence of an object, is implied; pure, if there
is no intermixture of sensation. We may call sensation the matter of
sensuous knowledge. Hence pure perception contains only the form
under which a definite object is perceived, and pure conception the form
in which an object in general is thought. Pure perceptions or pure con-
ceptions alone are possible a priori, while empirical perceptions or
empirical conceptions are possible only a posteriori.
If sensibility is the receptivity of the mind in the actual apprehen-
sion of some impression, understanding is the spontaneity of knowl-
edge, or the faculty that of itself produces ideas. We are so consti-
tuted that our perception always is sensuous; or it shows merely the
manner in which we are affected by objects. But, we have also under-
standing, or the faculty of thinking the object of sensuous perception.
Neither of these is to be regarded as superior to the other. Without
sensibility no object would be given to us, without understanding none
would be thought. Thoughts without content are empty, perceptions
without conceptions are blind. It is therefore just as necessary to make
our conceptions sensuous, that is, to add the object to them in percep-
tion, as it is to make our perceptions intelligible, that is, to bring them
under conceptions. Neither of these faculties or capacities can do the
work of the other. Understanding can perceive nothing, the senses can
think nothing. Knowledge arises only from their united action. But
this is no reason for confusing the function of either with that of the
other; it is rather a strong reason for carefully separating and distin-
guishing the one from the other. Hence it is, that we distinguish
Esthetic, as the science of the universal rules of sensibility, from Logic,
which is the science of the universal rules of understanding.
General logic, as distinguished from the special logic or organon of
a particular science, is either pure or applied ; but only the former is in
the strict sense a science. There are two rules that must ever be kept in
mind in pure general logic. ( i ) As general logic, it abstracts from all
content of thought, and from all distinction of objects, and deals only
with the pure form of thought. (2) As pure logic, it has no empirical
principles. Psychology has no influence on the canon of the under-
standing, and therefore it does not, as has sometimes been supposed,
'222 EIGHTEENTH CENTURY PHILOSOPHY
contribute anything to pure logic. Logic is a demonstrative science,
and whatever it contains must be certain entirely a priori
2. Transcendental Logic.
Pure general logic, then, abstracts from all the content of know-
ledge, or what is the same thing, from all relation of knowledge to its
objects, and considers merely the logical form implied in the relation of
one element of knowledge to another, or the universal form of thought.
Now, we have learned from the Transcendental Esthetic that there are
pure as well as empirical perceptions, and it may well be, that a similar
distinction obtains between the pure and the empirical thought of objects.
In that case, there will be a logic that does not abstract from all the con-
tent of knowledge. Containing merely the rules of the pure thought of
an object, it will exclude all knowledge, the content of which is empiri-
cal. It will also refer our knowledge of objects to its origin, in so far as
that origin cannot be ascribed to objects themselves.
Let us suppose, then, that there are conceptions which relate to
objects a priori, but which, as mere functions of pure thought, stand to
objects in quite a different relation from that in which perceptions stand
to them, whether these are pure or sensuous. As these conceptions will
IDC of neither empirical nor aesthetic origin, we get the idea of a science
•of pure understanding and pure reason, the aim of which is to examine
into the knowledge which we obtain by thinking objects completely a
priori. Such a science, as setting forth the origin, the limits, and the
objective validity of pure conceptions, we must call Transcendental
Logic.
3. Division of General Logic into Analytic and Dialectic
General logic analyzes the whole formal procedure of understand-
ing and reason into its elements, and presents these as principles by
which the logical validity of knowledge may be estimated. This part of
logic, which is well called Analytic, supplies a negative touchstone of
truth . . . but it does not enable us to determine positively any-
thing in regard to objects. At the same time, there is something so
seductive in an art that enables us to reduce all our knowledge to the
form of understanding, however empty and poor in content it may be,
that general logic, although it is merely a canon of judgment, is apt to
be used as an organon by means of which new truth, or rather the
specious appearance of new truth, may be obtained. When it is thus
misused as a supposed organon, logic is called Dialectic.
EIGHTEENTH CENTURY PHILOSOPHY 223
4. Division of Transcendental Logic into Analytic and Dialectic
Just as in Transcendental ^Esthetic we isolated the sensibility, so in
Transcendental Logic we shall isolate the understanding, and throw into
relief that element in our knowledge which has its origin in the under-
standing alone. This pure element can be employed in actual know-
ledge, only on condition that objects are presented in perception to which
it may be applied. For, without perception, the pure element of know-
ledge has no object, and therefore remains perfectly empty. That part
of Transcendental Logic which sets iorth the pure element in knowledge
that belongs to understanding, and the principles without which no
object whatever can be thought, is Transcendental Analytic. It is a
logic of truth, because no knowledge can contradict it without losing all
content, that is, all relation to an object, and therefore all truth. But
there is a very seductive and deceptive tendency to employ that pure
knowledge of understanding and those principles by themselves, and to
apply them even beyond the limits of experience. Only in experience,
however, can any matter or object be found to which the pure concep-
tions of understanding may be applied. There is thus a danger that
understanding, with a mere show of rationality, may make a material
use of its purely formal principles, and pass judgments upon all objects
without distinction, whether they are given to us or not, and perhaps
even although they cannot be given to us at all. That which is merely
a canon for the criticism of understanding in its empirical use, is mis-
used, when it is supposed to be an organon that may be employed uni-
versally and without restriction, and when it permits understanding to
venture upon synthetic judgments about objects in general, and to pro-
nounce and decide upon them. Pure understanding is then employed
dialectically. The second part of Transcendental Logic must therefore
consist of a criticism of dialectical illusion. It is called Dialectic, not
because it is an art of producing illusion dogmatically — a favourite art
of too many metaphysical jugglers — but because it is a criticism of
understanding and reason in their hyperphysical use; a criticism, the
aim of which is to expose their specious and groundless pretensions to
the discovery and extension of knowledge through purely transcendental
principles, and to preserve understanding from all sophistical illusion.
224 EIGHTEENTH CENTURY PHILOSOPHY
TRANSCENDENTAL ANALYTIC
CHAPTER I. GUIDING THREAD FOR THE DISCOVERY OF THE CATEGORIES
The first part of Transcendental Analytic deals with the concep-
tions, the second part with the judgments of pure understanding.
It is the privilege as well as the duty of transcendental philosophy,
to proceed in the search for its conceptions upon a definite principle ; for
these conceptions spring from the understanding pure and unmixed, and
must therefore be connected together in the unity of a single conception
or idea. This one fundamental conception is a systematic principle, by
the application of which we may be certain a priori that we have found
out all the pure conceptions of understanding, and have assigned to each
its proper place in the whole system.
Section I. — The Logical Use of Understanding
Understanding has already been defined, negatively, as a non-sensu-
ous faculty of knowledge. Now, as without sensibility we can have no
perception, understanding cannot be a faculty of perception. But, apart
from perception, the only other mode of obtaining knowledge is by
means of conceptions. Therefore the knowledge that is due to under-
standing, or at least to human understanding, is a knowledge by means
of conceptions ; it is not perceptive, but discursive. All perceptions, as
sensuous, rest upon affections, whereas conceptions rest upon functions.
By function I mean the unity of act, in which various ideas are brought
under a common idea. Conceptions are based upon the spontaneity of
thought, sensuous perceptions on the receptivity of impressions. Now,
the only use that understanding can make of these perceptions is to
judge by means of them. And, as without perception there is no direct
consciousness of an object, a conception is never related directly to an
object, but always indirectly, through a perception or through another
conception. Judgment is therefore the indirect knowledge of an object,
or the knowledge of knowledge. In every judgment there is a concep-
tion which holds true of various ideas, and, among others, of one which
is directly referred to an object. Thus, in the judgment that all bodies
are divisible, the conception of divisibility applies to various other con-
ceptions, but it is in an especial way related to the conception of body,
as this again is related to certain objects that we directly perceive. Of
these objects we are therefore conscious only indirectly in the concep-
tion of divisibility. Accordingly, all judgments are functions of unity,
because they do not consist in the direct knowledge of an object, but
EIGHTEENTH CENTURY PHILOSOPHY 225
bring that and other knowledge under the unity of a higher and more
comprehensive conception. And as we can reduce all acts of under-
standing to judgments, understanding itself may be said to be a faculty
of judgment. For, as we have seen above, understanding is the faculty
of thought. To think is to know by means of conceptions. But con-
ceptions, as predicates of possible judgments, are relative to the idea of
an object not yet determined. By the conception of body is meant
something — metal, for instance — which may be known by means of that
conception. Body is a conception, just because it contains under it other
determinations by means of which it may be referred to actual objects.
It is thus the predicate of a possible judgment, such as, that every metal
is a body. We may, therefore, find out all the possible functions of
judgment if we can but tell what are all the possible functions of unity
in judgment. And this, as we shall see in the next section, can quite
readily be done.
Section II. — 9. The Logical Function of Understanding in Judgment.
If we abstract from all the content of a judgment, and only pay
heed to the mere form of understanding, we find that the functions of
thought in judgment may be brought under four heads, each of which
contains three subdivisions. Thus we get the following table : —
I. Quantity of Judgments.
Universal.
Particular.
Singular.
2. Quality. 3. Relation.
Affirmative. Categorical.
Negative. Hypothetical.
Infinite. Disjunctive.
4. Modality.
Problematic.
Assertoric.
Apodictic.
Section HI. — 10. The Pure Conceptions of Understanding or
Categories.
General Logic, as has been said, abstracts from all the content of
knowledge, and looks to some other source, whatever that may be, for
the content that it is to transform by analysis into conceptions. Trans-
cendental Logic, on the other hand, has lying before it a complex of
a priori sensibility, which it receives from Transcendental Esthetic;
without this complex, as a material upon which to operate, the concep-
226 EIGHTEENTH CENTURY PHILOSOPHY
tions of pure understanding would be without content or perfectly
empty. Now, space and time have not only themselves, as pure a priori
perceptions, a complexity of content; but, as they are the conditions
without which the mind could not be receptive of impressions, and
therefore could not be conscious of objects, they must always affect our
conception of objects. Conception, however, is due to the spontaneous
activity of thought, and hence the complex content of pure perception
must first be surveyed, taken up into thought and combined, before there
can be any knowledge. This act I call synthesis.
By synthesis, in its most general sense, is meant the act of putting
various ideas together and grasping their multiplicity in one conscious-
ness. Such synthesis is pure, if the multiplicity is given, not empirically
but a priori, as in the case of space and time. Now, before we can
analyze any idea, we must first have the idea, and hence the content of a
conception cannot originally come into consciousness by analysis. It is
by synthesis of various elements, whether those elements are given
empirically or a priori, that we first get knowledge. No doubt the syn-
thesis may at first be crude and confused, and it may stand in need of
analysis, but yet it is by synthesis that the various elements are gathered
together and united in the knowledge of a certain concrete object. It is
to synthesis, therefore, that we must first direct our attention, if we
would learn the true origin of our knowledge.
Synthesis in general, as we shall afterwards see, is due solely to the
operation of imagination, a blind but indispensable function of the soul,
without which we should have no knowledge whatever, but of which we
are seldom ever conscious. To bring this synthesis to conceptions is the
function of understanding, and it is only by this operation of under-
standing that we obtain what can properly be called knowledge.
Pure synthesis, viewed in its most general aspect, is the pure con-
ception of understanding. By this pure synthesis I understand that
which rests upon a basis of a priori synthetic unity. Thus in arith-
metical addition, as is readily seen in the case of larger numbers, the syn-
thesis conforms to a conception, because it proceeds on a common basis
of unity, as, for instance, the decade. By this conception the unity in the
synthesis of a complex is made necessary.
By analysis various ideas are brought under a single conception, as
is shown in general logic. But it belongs to transcendental logic to
tell us how the pure synthesis of ideas is brought to conceptions. The
first element that enters into the knowledge of all objects a priori is the
complex content of pure perception. The second element is the syn-
EIGHTEENTH CENTURY PHILOSOPHY 227
thesis of this content by imagination. But as even this is not enough to
constitute knowledge, a third element is supplied by understanding, in
the conceptions which give unity to this pure synthesis, and which con-
sist solely in the consciousness of this necessary synthetic unity.
The same function which gives unity to various ideas in a judg-
ment also gives unity to the mere synthesis of various ideas in a per-
ception; and this synthesis, in its most general expression, is the pure
conception of understanding. Understanding at once gives analytic
unity to conceptions, and synthetic unity to the complex content of per-
ception; and indeed the logical form of judgment presupposes and rests
upon the very same acts of thought as those by which a transcendental
content is given to the various determinations of our consciousness.
Hence it is that the pure conceptions of understanding, as they are fitly
called, apply to objects a priori, and therefore do not fall within the
view of general logic.
In this way there arises exactly the same number of pure concep-
tions of understanding, applying a priori to all objects of perception, as
there are logical functions of judgments in the preceding table ; for those
functions completely specify understanding, and give a perfect measure
of its powers. We shall call the pure conceptions categories, after
Aristotle, because our object is the same as his, although our method
and results are widely different.
TABLE OF CATEGORIES
i. Quantity.
Unity.
Plurality.
Totality.
2. Quality. 3. Relation.
Reality. Inherence and Subsistence
(substantia et accidens)
Negation Causality and Dependence
(cause and effect).
Limitation. Community (reciprocity between
the active and the passive).
4. Modality.
Possibility - Impossibility.
Existence - Non-existence.
Necessity - Contingency.
This, then, is a list of all the primary pure conceptions of synthesis
223 EIGHTEENTH CENTURY PHILOSOPHY
that understanding contains within itself a priori. Because it contains
these pure conceptions, it is called pure understanding, and only by them
can it understand anything in the complex content of perception, that is,
think an object. The table has not been left to the uncertain suggestions
of empirical induction, but has been drawn up systematically, on the
basis of a single principle, namely, the faculty of judgment, or, what is
the same thing, the faculty of thought.
The table of categories suggests some nice points, which, perhaps,
might be found to have an important bearing on the scientific form of
all knowledge of reason. ( I ) The four classes of categories naturally
fall into two groups; those in the first group being concerned with
objects of perception, pure as well as empirical, while those in the sec-
ond group are concerned with the existence of those objects, as related
either to one another or to understanding. The first may be called the
mathematical, the second the dynamical categories. The former, as is
obvious, have no correlates, the latter have correlates. This distinction
must have some ground in the nature of understanding. (2) It is also
suggestive that the number of categories in each class is three, because
usually all a priori division must be by dichotomy. To this it must be
added that the third category in each class arises from the union of the
second category with the first. Thus totality or allness is just plurality
regarded as unity, limitation is reality combined with negations, com-
munity is causality in which two substances mutually determine one
another, and lastly, necessity is just existence given by mere possibility.
CHAPTER II. DEDUCTION OF THE CATEGORIES
13. Principles of a Transcendental Deduction.
There is a distinction in law between the question of right (quid
juris) and the question of fact (quid facti). Both must be proved, but
proof of a right or claim is called its deduction. Now, among the vari-
ety of conceptions that make up the very mixed web of human knowl-
edge, there are certain conceptions that put in a claim for use entirely
a priori, and this claim of course stands in need of deduction. It is use-
less to refer to the fact of experience in justification of such a claim,
but at the same time we must know how conceptions can possibly refer
to objects of experience, although those objects have not been derived
from experience. An explanation of the manner in which conceptions
can relate a priori to objects, I call a transcendental deduction ; and from
it I distinguish an empirical deduction, which simply tells us how a con-
EIGHTEENTH CENTURY PHILOSOPHY 223
ception has been acquired by experience and reflection on experience.
The former proves our right to the use of a certain conception ; the latter
merely points out that as a matter of fact it has come into our posses-
sion in a certain way.
We had no difficulty in explaining1 how space and time, although
they are themselves known a priori, are yet necessarily related to objects,
and make possible a synthetic knowledge of objects which is independent
of all experience. For, as it is only by means of these pure forms of
sense that we can be conscious of an object in empirical perception, space
and time are pure perceptions, which contain a priori the condition of
the possibility of objects as phenomena, and therefore synthesis in them
has objective validity.
The categories of understanding, on the other hand, are not condi-
tions under which objects are given in perception; hence objects might
certainly be presented to us, even if they were not necessarily related to
functions of understanding, as their a priori condition. Here, there-
fore, a difficulty arises that we did not meet with in the field of sensi-
bility. The difficulty is, how subjective conditions of thought should
have objective validity, or, in other words, how they should be condi-
tions without which no knowledge of objects would be possible. Take,
for instance, the conception of cause. Here we have a peculiar sort of
synthesis, in which something B is conceived as following upon some-
thing else quite different A, in conformity with a rule. It is hard to see
why phenomena should be subject to such an a priori conception. Why
should not the conception be perfectly empty, and without any phenom-
enal object corresponding to it?
We cannot avoid the toil of such investigations by saying that expe-
rience is perpetually giving us examples of such conformity to law on
the part of phenomena, and that we are thus enabled to form an abstract
conception of cause, and to be certain of its objective validity. The con-
ception of cause cannot possibly originate in that way; and hence we
must either show that it rests completely a priori upon understanding,
or we must discard it altogether as a mere fiction of the brain. For the
conception demands that something A should be of such a nature that
something else B follows from it necessarily, and in conformity with an
absolutely universal rule. No pure conception of understanding can be
the product of empirical induction without a complete reversal of its
nature and use.
The transcendental deduction of all a priori conceptions must there-
230 EIGHTEENTH CENTURY PHILOSOPHY
fore be guided by the principle, that these conceptions must be the a
priori conditions of all possible experience. Conceptions which make
experience possible are for that very reason necessary. An analysis of
the experience in which they occur would not furnish a deduction of
them, but merely an illustration of their use. Were they not the pri-
mary conditions of all the experience in which objects are known as
phenomena, their relation to even a single object would be utterly
incomprehensible.
Section II. — A Priori Conditions of Experience.
It would be quite a sufficient deduction of the categories, and justi-
fication of their objective application, to show that, apart from them, no
object whatever is capable of being thought. But there are two reasons
why a fuller deduction is advisable: firstly, because, in thinking an
object, other faculties besides understanding, or the faculty of thought
proper, come into play; and, secondly, because it has to be explained
how understanding can possibly be a condition of the knowledge of real
objects. We must, therefore, begin with a consideration of the pri-
mary activities of the subject that are essential in the constitution of
experience ; and these we must view, not in their empirical, but in their
transcendental character.
If consciousness were broken up into a number of mutually repel-
lant states, each isolated and separated from the rest, knowledge would
never arise in us at all, for knowledge is a whole of related and con-
nected elements. When, therefore, I call sensible perception a synopsis,
in order to mark the complexity of its content, it must be remembered
that in this synopsis a certain synthesis is implied, and that knowledge is
possible only if spontaneity is combined with receptivity. This is the
reason why we must say that in all knowledge there is a three-fold syn-
thesis : firstly, the apprehension in perception of various ideas, or modi-
fications of the mind ; secondly, their reproduction in imagination ; and,
thirdly, their recognition in conception. These three forms of synthesis
point to three sources of knowledge, which make understanding itself
possible, and through it all experience as an empirical product of under-
standing.
I. Synthesis of Apprehension in Perception.
Whatever may be the origin of our ideas, whether they are due to
the influence of external things or are produced by internal causes,
whether as objects they have their source a priori or in experience, as
modifications of the mind they must all belong to the inner' sense. All
EIGHTEENTH CENTURY PHILOSOPHY 231
knowledge is, therefore, at bottom subject to time as the formal condi-
tion of inner sense, and in time every part of it without exception
must be ordered, connected, and brought into relation with every other
part. This is a general remark, which must be kept in mind in the
whole of our subsequent inquiry.
We should not be conscious of the various determinations that
every perception contains within itself were we not, in the succession of
our impressions, conscious of time. If each feeling were limited to a
single moment, it would be an absolutely individual unit. In order that
the various determinations of a perception, as, for instance, the parts of
a line, should form a unity, it is necessary that they should be run over
and held together by the mind. This act I call the synthesis of appre-
hension. It is apprehension, because it goes straight to perception; it
is synthesis, because only by synthesis can the various elements of per-
ception be united in one object of consciousness.
Now, this synthesis of apprehension must be employed a priori also,
or in relation to determinations not given in sensible experience. Other-
wise we should have no consciousness of space and time a priori, for
these can be produced only by a synthesis of the various determina-
tions that are presented by sensibility in its original receptivity. There
is therefore a pure synthesis of apprehension.
2. Synthesis of Reproduction in Imagination.
There is an empirical law of the association of ideas. When any two
ideas have followed, or accompanied each other, an association between
them is at last formed, and they are so connected that, even when an
object is not present, the mind passes from the one to the other in con-
formity with a fixed rule. But this law of reproduction presupposes that
phenomena are themselves actually subject to such a rule, and that
the various elements in these phenomena of which \ve are conscious
should accompany or follow one another in accordance with certain
rules. Or any other supposition our empirical imagination would have
nothing to reproduce in any way conforming to its own nature, and
would therefore lie hidden in the depths of the mind as a dead, and to us
unknown faculty. Were cinnabar, for instance, sometimes red and
sometimes black, sometimes light and sometimes heavy; or were the
same name given at one time to this object, and at another time to that,
without the least regard to any rule implied in the nature of the phe-
nomena themselves, there could be no empirical synthesis of reproduc-
tion.
232 EIGHTEENTH CENTURY PHILOSOPHY
There must, therefore, be something which makes the reproduction
of phenomena possible at all, something which is the a priori ground of
a necessary synthetic unity. That this is so, we may at once see, if we
reflect that phenomena are not things in themselves, but are merely the
play of our own ideas, and therefore at bottom determinations of the
inner sense. Now, if we can show that even our purest a priori percep-
tions can yield knowledge, only in so far as they involve such a com-
bination as makes a thoroughgoing synthesis of reproduction possible,
we may conclude that this synthesis of imagination, being prior to all
experience, rests upon a priori principles. We must then assume a
pure transcendental synthesis as the necessary condition of all experi-
ence, for experience is impossible unless phenomena are capable of being
reproduced. Now, if I draw a line in thought, or think of the time
from one day to another, or even think of a certain number, it is plain
that I must be conscious of the various determinations one after the
other. But if the earlier determinations — the prior parts of the line,
the antecedent moments of time, the units as they arise one after the
other — were to drop out of my consciousness, and could not be repro-
duced when I passed on to the later determinations, I should never be
conscious of a whole; and hence not even the simplest and most ele-
mentary idea of space or time could arise in my consciousness.
The synthesis of reproduction is therefore inseparably bound up
with the synthesis of apprehension. And as the synthesis of apprehen-
sion is the transcendental ground of the possibility of all knowledge —
of pure a priori as well as empirical knowledge — the reproductive syn-
thesis of imagination belongs to the transcendental functions of the
mind, and may therefore be called the transcendental faculty of imag-
ination.
3. Synthesis of Recognition in Conceptions.
Were I not conscious that what I think now is identical with what
I thought a moment ago, all reproduction in the series of ideas would
be useless. The idea reproduced at a given moment would be for me a
perfectly new idea. There would be no identical consciousness bound
up with the act of producing one idea after another ; and as without such
consciousness there could be for me no unity, I should never be con-
scious of the various members of the series as forming one whole. If,
in counting, I should forget that the units lying before my mind had
been added by me one after the other, I should not be aware that a sum
was being produced or generated in the successive addition of unit to
EIGHTEENTH CENTURY PHILOSOPHY 233
unit; and as the conception of the sum is simply the consciousness of
this unity of synthesis, I should have no knowledge of the number.
At this point it is necessary to have a clear idea of what we mean
by an object of consciousness. We have seen that a phenomenon is just
a sensation of which we are conscious, and that no sensation can be said
to exist by itself as an object outside of consciousness. What, then, do
we mean when we speak of an object as corresponding to our know-
ledge, and therefore as distinct from it ? It is easy to see that this object
can be thought of only as something=jtr, for there is nothing beyond
knowledge that we can set up as contrasted with knowledge, and yet
as corresponding to it.
It is plain that in knowledge we have to do with nothing but the
various determinations of our own consciousness ; hence the object— ;r,
which corresponds to these determinations, if it is supposed to be dis-
tinct from every object of consciousness, is for us nothing at all. The
unity which the object demands can be only the formal unity of con-
sciousness in the synthesis of its various determinations. In saying that
we know the object, we mean that we have introduced synthetic unity
into the various determinations of perception. But this is impossible, if
the perception could not be produced by a function of synthesis, which,
in conforming to a rule, makes the reproduction of those determinations
a priori necessary, and renders possible a conception that unites them.
There can be no knowledge without a conception, however indefin-
ite or obscure it may be, and a conception is in form always a universal
that serves as a rule. The conception of body, for instance, as a unity
of the various determinations thought in it, serves as a rule in our knowl-
edge of external phenomena. Now, it is always a transcendental condi-
tion that lies at the foundation of that which is necessary. There must,
therefore, be a transcendental ground of the unity of consciousness in
the synthesis of the various determinations implied in every perception ;
and this ground must be necessary to the conception of any object what-
ever, and therefore to the conception of every object of experience. In
no other way can there be any object for our perceptions ; for the object
is nothing but that something=.r, the conception of which involves
necessity of synthesis.
This original and transcendental condition is just transcendental
apperception. The consciousness, in internal perception, of oneself as
determined to certain states, is merely empirical, and is always chang-
ing. In the flux of inner phenomena there can be no unchanging or
V 6-15
234 EIGHTEENTH CENTURY PHILOSOPHY
permanent self. This form of self-consciousness is usually called
inner sense or empirical apperception. Now, from empirical data it is
impossible to derive the conception of that which must necessarily be
numerically identical. What we require, in explanation of such a trans-
cendental presupposition, is a condition that precedes all experience, and
makes it possible.
No knowledge whatever, no unity and connection of objects, is pos-
sible for us, apart from that unity of consciousness which is prior to all
data of perception, and without relation to which no consciousness of
objects is possible. This pure, original, unchangeable consciousness I
call transcendental apperception. That this is the proper name for it is
evident, were it only that even the purest objective unity, that of the
a priori conceptions of space and time, is possible only in so far as per-
ceptions are related to it. The numerical unity of this apperception is,
therefore, just as much the a priori foundation of all conceptions as the
various determinations of space and time are the a priori foundation of
the perceptions of sense.
It is this transcendental unity of apperception which connects all
the possible phenomena that can be gathered together in one experience,
and subjects them to laws. There could be no such unity of conscious-
ness were the mind not able to be conscious of the identity of function,
by which it unites various phenomena in one knowledge. The original
and necessary consciousness of the identity of oneself is at the same
time the consciousness of a necessary unity in the synthesis of all phe-
nomena according to conceptions. These conceptions are necessary
rules, which not only make phenomena capable of reproduction, but
determine perception as perception of an object, that is, bring it under a
conception of something in which various determinations are necessarily
connected together. It would be impossible for the mind to think of
itself as identical in its various determinations, and indeed to think that
identity a priori, if it did not hold the identity of its own act before its
eyes, and if it did not, by subjecting to a transcendental unity all the
synthesis of empirical apprehension, make the connection of the various
determinations implied in that synthesis possible in accordance with
a priori rules.
17. The synthetic Unity of 'Apperception is the Supreme Principle of
Understanding.
In the Transcendental ^Esthetic, we have seen that the supreme
principle, without which perception in its relation to sensibility is impos-
EIGHTEENTH CENTURY PHILOSOPHY 235
sible, is that all the determinations of perception should stand under the
formal conditions of space and time. Now, the supreme principle, with-
out which perception, in its relation to understanding is impossible, is,
that all determinations of perception should stand under conditions of
the original synthetic unity of apperception. Under the former stand all
determinations of perception, in so far as they are given to us ; under
the latter, in so far as they must be capable of being combined in
one consciousness. Apart from the synthetic unity of appercep-
tion, nothing can be thought or known, because the determinations
given in perception, not having the act of apperception, "I think," in
common, would not be comprehended in one self-consciousness.
Speaking quite generally, understanding is the faculty of knowl-
edge. Knowledge consists in the consciousness of certain given deter-
minations as related to an object. An object, again, is that, in the
conception of which the various determinations of a given perception are
united. Now, all unification of determinations requires unity of con-
sciousness in the synthesis of the determinations. Hence, the unity of
consciousness is absolutely necessary, to constitute the relation of deter-
minations to an object, give them objective validity, and make them
objects of knowledge; and on that unity therefore rests the very possi-
bility of understanding.
The principle of the original synthetic unity of apperception, as
being completely independent of all conditions of sensuous perception, is
the supreme condition of the pure use of understanding, and upon this
pure use rests the whole of its empirical use. Space, as the mere form
of external sensuous perception, does not of itself yield any knowl-
edge; it but supplies the various elements of a priori perception that
are capable of becoming knowledge. To know anything spatial, as, for
instance a line, I must draw it, and so produce by synthesis a definite
combination of the given elements. Thus, the unity of the act of com-
bination is at the same time the unity of the consciousness in which the
line is thought, and only in this unity of consciousness is a determinate
space known as an object. The synthetic unity of consciousness is,
therefore, an objective condition of all knowledge. It is not merely a
condition which I must observe in knowing an object, but it is a condi-
tion under which every perception must stand, before it can become an
object for me at all. Without this synthesis, the various determinations
would not be united in one consciousness.
Although it is thus proved, that the synthetic unity of conscious-
236 EIGHTEENTH CENTURY PHILOSOPHY
ness is the condition of all thought, the unity of consciousness, as has
been already said, is in itself an analytic proposition. For, it says only,
that all the determinations of which I am conscious in a given percep-
tion must stand under the condition, which enables me to regard them
as mine, or as related to my identical self, and so to comprehend them
as synthetically combined in one apperception, through the "I think"
expressed in all alike.
But this is not the principle of every possible understanding,
but only of an understanding, through the pure apperception of which,
in the consciousness "I am," no determinations are given. If we had an
understanding, which, by its mere self-consciousness, presented to itself
the manifold determinations of perception ; an understanding, which, by
its very consciousness of objects, should give rise to the existence of
these objects ; such an understanding would not require, for the unity
of consciousness, a special act of synthesis of manifold determinations.
But this act of synthesis is essential to human understanding, which
thinks, but does not perceive. It is, indeed, the supreme principle of
human understanding. Nor can we form the least conception of any
other possible understanding, whether of one that itself perceives, or of
one that is dependent upon sensibility for its perception, but not upon a
sensibility that stands under the same conditions of space and time.
18. Objective Unity of Self-consciousness.
The transcendental unity of apperception is that unity through
which all the determinations given in a perception are united in a con-
ception of the object. It is, accordingly, called objective, and must be
distinguished from the subjective unity of consciousness, which is a
determination of the inner sense, through which the complex of percep-
tion is given empirically to be combined into an object. Whether I shall
be empirically conscious of certain determinations as simultaneous,
or as successive, depends upon circumstances, or empirical conditions.
Hence, the empirical unity of consciousness, through the associa-
tion of the elements of perception, is itself a phenomenon, and is per-
fectly contingent. But the pure form of perception in time, as merely
perception in general, stands under the original unity of consciousness
just because the various determinations given in it are necessarily related
to an "I think." It therefore stands under that original unity by means
of the pure synthesis of understanding, which is the a priori ground of
the empirical synthesis. Only the original unity of apperception is
objective; the empirical unity, with which we are not here concerned,
EIGHTEENTH CENTURY PHILOSOPHY 237
and which besides is only derived from the other, under given condi-
tions in concrete, is merely subjective. To one man, for instance, a
certain word suggests one thing, to another a different thing. In what
is empirical, the unity of consciousness does not hold necessarily and
universally of that which is given.
19. The Logical Form of all Judgments consists in the objective unity of
the conceptions they contain.
A judgment is simply the way in which given ideas are brought to
the objective unity of apperception. This is the force of the copula
"is," which just marks the distinction between the objective unity and
the subjective unity of given ideas. It indicates their relation to the
original apperception, and their necessary unity. This holds good even
if the judgment is itself empirical and therefore contingent. I do not
mean, that, in the proposition, "Bodies are heavy," the idea of heavy is
necessarily connected with the idea of body in empirical perception, but
that they are connected with each other in the synthesis of perceptions
through the necessary unity of apperception. That is to say, the two
ideas are connected with each other in conformity with the principles by
which ideas are objectively determined and become knowledge. Now,
those principles are all derived from the supreme principle of the trans-
cendental unity of apperception. Through this principle alone, ideas are
related in the way of judgment, and become objectively valid. Thus we
get a sufficient test of the distinction between the relation of ideas in a
judgment, and a relation of the same ideas that is only of subjective
validity, as, for instance, a relation depending upon the laws of associa-
tion. In the latter case, all that I could say would be, that if I lift a body;
I have a sensation of weight, but not, that the body is heavy. To say
that the body is heavy, means, that the two ideas of heavy and body are
connected together in the object, whatever the state of the subject may
be, and not merely that they are contiguous in my observation, repeat it
as often as I please.
20. AH sensuous Perceptions stand under the Categories as conditions
under -which alone their various determinations can come
together in one consciousness.
The various determinations given in a sensuous perception stand
under the original synthetic unity of apperception, because in no other
way could there possibly be any unity of perception (17). But that act
of understanding, by which the determinations given in consciousness,
whether these are perceptions or conceptions, are brought under a single
238 EIGHTEENTH CENTURY PHILOSOPHY
apperception, is the logical function of the judgment (19). Hence, all
the elements given in an empirical perception are determined by one of
the logical functions of judgment, and thus brought into one conscious-
ness. But the categories are just the functions of judgment, in so far
as these are applied in determination of the various elements of a given
perception (13). Therefore, the various determinations in a given per-
ception necessarily stand under the categories.
2,2. The Category has no other application in Knowledge than to objects
of Experience.
To think an object is not the same thing as to know it. Knowledge
involves two elements : firstly, the conception or category, by which an
object in general is thought; secondly, the perception by which it is
given. If no perception could be given, corresponding to the concep-
tion, I should no doubt be able to think an object so far as its form was
concerned, but as there would be no object in which that form was real-
ized, I could not possibly have knowledge of any actual thing. So far
as I could know, there would be nothing, and could be nothing, to which
my thought might be applied. Now, the Esthetic has shown to us that
all the perception that we can have is sensuous ; hence the thought of an
object in general, by means of a pure conception of understanding, can
become knowledge, only by being brought into relation with objects of
sense. Sensuous perception is either the pure perception of space and
time, or the empirical perception of that which is directly presented
through sensation as actually in space and time. By the determination
of space and time themselves, we can obtain that a priori knowledge of
objects which mathematics supplies. But this knowledge is only of the
form of phenomena, and it is still doubtful if actual things must be per-
ceived in this form. Mathematical conceptions, therefore, can be called
knowledge, only if it is presupposed that there are actual things which
cannot be presented to us except under the form of that pure sensuous
perception. Now, things in space and time are given to us only through
empirical observation, that is, in perceptions that are accompanied by
sensation. Hence, the pure conceptions of understanding, even if they
are applied to a priori perceptions, as in mathematics, do not yield a
knowledge of things. Before there can be any knowledge, the pure
perceptions, and the conceptions of understanding through the medium
of pure perceptions, must be applied to empirical perceptions. The cate-
gories, therefore, give us no knowledge of actual things, even with the
aid of perception, except in so far as they are capable of being applied
EIGHTEENTH CENTURY PHILOSOPHY 239
to empirical perception. In other words, they are merely conditions of
the possibility of empirical knowledge. Now, such knowledge is called
experience. Hence the categories have a share in the knowledge of
those things only, that are objects of possible experience.
The above proposition is of the greatest importance, for it marks
out the limits of the pure conceptions of understanding in their appli-
cation to objects, just as Transcendental Esthetic marked out the limits
of the pure forms of sensuous perception. Space and time are but the
conditions under which objects that are relative to our senses are capable
of being presented to us, and therefore they apply only within the limits
of experience. Beyond those limits they have no meaning whatever, for
they are only in the senses, and have no reality apart from them. The
pure conceptions of understanding are free from this limitation, and
extend to objects of perception of any kind, whether that perception is
like or unlike ours, if only it is sensuous and not intellectual. But this
extension of conception beyond our sensuous perception does not help us
in the least. For, the conceptions are in that case quite empty, and we
are therefore unable even to say that there are any objects corresponding
to them. They are mere forms of thought without objective reality, for
we have no perception at hand, and therefore no object, to which the syn-
thetic unity of apperception, which is the sole content of those forms of
thought, could be applied. Only our sensuous and empirical perception
can give to them meaning and reality.
If I suppose an object of a non-sensuous perception to be given, I
can, no doubt, think of it as having all the predicates implied in my pre-
supposition. I can say that the object has none of the determinations
proper to sensuous perception ; that it is not extended or in space, that its
duration is not time, that there is in it no change or succession of states
in time, etc. But no real knowledge of an object is gained by merely
indicating how it is not perceived, so long as I cannot tell what is the
content of its perception. I cannot in that way understand even the pos-
sibility of an object to which my pure perception could apply, for I am
unable to bring forward a perception corresponding to such an object,
and can say only that my perception can never bring me into contact with
it. But what most concerns us here, is that to a thing of that nature, not
even a single category could be applied. I could not say, for instance,
that such a thing is a substance, that is, a thing that can exist as subject,
but never as mere predicate. For, how could I apply the conception of
substance, when, in the absence of all empirical perception, I should not
«ven know that anything corresponding to my idea could exist at all. —
From Watson's Selections ;
240
EIGHTEENTH CENTURY SCIENCE
THE SEVENTEENTH CENTURY had been made memorable in the sci-
ences by the discoveries of Galileo and Kepler in astronomy, of Harvey r
Leeuwenhoeck, Malpighi and Grew in biology, of Boyle in chemistry,
and of Guericke, Newton, Huyghens and Roemer in physics. Thus as-
tronomy was put upon a firm foundation and much was done for physics.
The eighteenth century was to see in physics the opening up of the field
of electricity, and the first beginning of the conception of heat in terms
of motion; the foundation of modern chemistry and geology, and the
development in astronomy of the nebular hypothesis of the growth of
the universe.
The century opened (1701) with the first attempts in organic chem-
istry made by Boerhaave. He decomposed organic substances such as
plants by sublimation and showed that the substances in the plants are
taken up from the earth in which they grow after first being dissolved in
the water that soaks down from the rains. He followed up these facts
by showing that animals are made up of reorganized vegetable matter.
His analyses were, of course, imperfect, because chemistry knew nothing
as yet of even such elements as oxygen, hydrogen, nitrogen or carbon,
the chief components of organisms. In fact, during the first half of the
century, chemistry was retarded by the acceptance of Stahl's phlogiston
theory, which was that burning is the release of an imaginary substance
called phlogiston, supposed to exist in all things capable of combustion.
In botany the work of the century was mostly descriptive and sys-
tematizing by Linnaeus.
Haller and Hunter made a beginning in comparative anatomy by
EIGHTEENTH CENTURY SCIENCE 241
trying to compare similar organs in different animals, and Buffon at-
tempted to describe all the known animals of the globe.
In physics the latter half of the century opened with the demonstra-
tion of the identity of electricity with lightning by Franklin (1752).
Hitherto electricity had been a plaything. Franklin showed that it is in
reality a giant. In 1760 Black discovered latent heat and in 1765 Watt
applied the principle to the construction of the first practical steam-
engine. Galvani (in 1789) found electricity to be present in animals
and noted its effects in contracting the muscles. Volta in 1792 discov-
ered chemical electricity and invented his battery, or "voltaic pile," to
produce it. Rumford by studying the effect of motion in producing
heat gave the old caloric theory that heat is a substance a severe shock,
and opened the way for the nineteenth century conception of the con-
servation of energy.
In the latter half of the century Hutton and Smith laid the first
foundation in geology by studying the formation of the earth.
In astronomy the century ended with a theory of the development
of the universe. Lagrange (1736-1813) and Laplace (1749-1827)
worked out mathematically the oscillations in the solar system caused by
the interaction of its parts and showed its stability. Herschel (1738-
1822) discovered the planet Uranus in 1781 ; found pairs of stars revolv-
ing round each other, thus demonstrating that the law of gravitation
holds not only in our solar system but in the universe ; showed that our
solar system seems to be moving in a mass toward the far-off constella-
tion of Hercules, and pointed out that some star clusters seem to con-
sist of dispersed "star-matter" or gases. On these foundations Laplace
built his hypothesis of the development of the universe from original
gases.
Meantime, toward the close of the century, chemistry had supplied
the conception of such gases. In 1756 Black by pouring acidulated
water on limestone discovered carbonic acid gas; in 1766 Cavendish
obtained hydrogen by pouring sulphuric acid and water on zinc. In
1774 Priestley procured oxygen by heating mercuric oxide, and later
(1784) Cavendish combined this new gas with hydrogen by means of
an electric spark passed through the mixture and found that they made
water. Lavoisier revolutionized chemistry (1778) by showing that all
combustion is the effect of combination with oxygen, thus overthrowing
the old phlogiston theory. Chemistry had begun to grasp the elements
of matter, and was on the high road toward being an exact science.
242
BOERHAAVE
HERMAN BOERHAAVE was born near Leyden, December 31, 1668,
and died Professor of Medicine and Botany at Leyden, September 23,
1738. In medicine he was the most representative man of his time, but
he was something of an eclectic in his beliefs and stands for no great ad-
vance in the subject. In chemistry, as noted previously, he did a great
deal toward starting the study of physiological chemistry by his inves-
tigations into the growth of plants as related to the substances ab-
sorbed from the soil.
PHYSIOLOGICAL CONCEPTIONS
In order to discover Truth in this manner by observation and rea-
son, it is requisite we should fix on some principles whose certainty and
effects are demonstrable to our senses, which may serve to explain the
phenomena of natural bodies, and account for the accidents that arise
in them; such only are those which are purely material in the human
body, with mechanical and physical experiments; for we are not sen-
sible of any other way of attaining to a true knowledge of the universal
and particular affections of bodies.
Demonstration is an evident proof of some dubious proposition,
so that nobody who admits the general principles, can deny their assent ;
these are purest in the mathematics, though there are many demon-
strations no less evident in physic, especially those which are taken
from anatomy. But there is no necessity for the principles of any art to
be proved in that art, it is sufficient if their certainty is by any means
demonstrated in other arts.
These ought to be first adjusted with distinction, clearness, and
certainty ; with distinction, which points out one being from any other ;
as if one was to define a circle to be a right line continued upon a point
till one end meets again with the other ; with clearness, which consists of
simple notions or ideas, easily conceived by any man in his senses, as
EIGHTEENTH CENTURY SCIENCE 243
that two and two joined make four; with certainty, which cannot be
denied by any reasonable person, or which must always appear true
upon examination.
The universal laws of nature, or affections of all bodies, depend
on mechanical and physical principles, upon which alone their actions
are explicable ; the same laws are also true in the human body, for its
matter appears to be universally the same with that of all other bodies ;
so that what may be said to be true of all bodies, may be also affirmed
true in our own. Thus, if one should affirm, that by the friction of two
bodies would arise heat, the same will also be true upon the friction of
solid parts in the human body. But then there are other principles not
to be explained by these universal laws, but by some particular disposi-
tion in the certain body ; these properties are called physical. But a
physician ought to consider both the affections of bodies in general,
as well as those only proper to the human body, that from a judicious
comparison and just reasoning, he may never subject the human body
to those laws only, to which the generality of, but not all, bodies are
liable.
26. But as there are in the human body many other appearances
not intelligible upon those principles, they therefore are not to be dem-
onstrated and explained by such principles ; if we would avoid error
we must take a very different course for that purpose ; this will readily
appear to any one who considers and admits for true the following
propositions, which are elsewhere demonstrated :
Such as memory, understanding, reason and the knowledge of
past and future appearances; which are peculiar to the mind, a being
without figure or extension, and conscious of pleasure and pain.
27. We are to consider ( I ) that Man is composed of a body and
•mind, united to each other; (2) that the nature of these are very dif-
ferent, and that therefore, (3) each has a life, actions and affections
differing from the other; yet (4) that there is such a reciprocal con-
nection and consent between the particular thoughts and affections of
the mind and the body, that a change in one always produces a change
in the other, and the reverse; also (5) that the mind performs some
actions by mere thought, without any effect upon the body; and that
it has other thoughts, which arise barely from some change in the con-
dition of the body; on the other hand, also, (6) that there are some
actions performed by the body without the attention, knowledge, or
desire of the mind, which is neither concerned therein as the cause or
effect of those actions; that there are also some ideas formed in the
244 EIGHTEENTH CENTURY SCIENCE
of a person in health by its past actions; and, lastly, that there
are other ideas compounded both of the past and present. That (7)
whatever we observe to arise from thought in the human body, is to
be only ascribed to the mind as the cause. But (8) that every appear-
ance which has solidity, figure, or motion, is to be ascribed to the body
and its motion for a principle, and ought to be demonstrated and
explained by their properties. That (9) we cannot understand or
explain the manner in which the body and mind reciprocally act upon
each other from any consideration of their nature separate; we can
only (10) remark by observation their effects upon each other, with-
out explaining them, and when any difficulty or appearance has been
traced so far, that it only remains to explain the manner of their recip-
rocal action, we are to suppose such account satisfactory, both because
it may be sufficient for all the purposes of the physician, and as it is
impossible for him to search any further.
By the body we understand that part of us which is extended in
three dimensions, has a form, and is fitted for motion, or rest, etc.
By the mind we understand that being which thinks, and perceives
itself thinking, and the thing thought of.
The union of the body and mind is such, that the mind cannot
resist forming to itself the ideas of pleasure and pain, when the body is
in a particular manner affected ; nor can the healthy body refuse to obey
the action of the mind under particular circumstances.
By the nature of the body or mind, we understand everything
which we are satisfied belong to each. The essential nature of the mind
is to be conscious, or to think ; but to think of this and that particular
thing, is accidental to it. The essential nature of the body is exten-
sion and resistance. These attributes have nothing in common to each
other, nor ought one to conclude from similitude, that two beings are
reducible to one general class. When I think of extension, it does not
infer anything of thought; and when I reflect upon thought, I can
perceive no connexion of it with extension; therefore the idea of the
body has nothing in common with that of the mind, and the reverse.
In the same manner, there is no connexion between the common ideas
of time, sound, gravity, light, etc. Socrates made a proper answer
to Crito, when he was asked in what place he should choose to be buried ?
viz. "You will not find Socrates when you prepare my tomb, nor shall I
be sensible of what you then do for me." Nor are the reasons wanting
EIGHTEENTH CENTURY SCIENCE 245
to prove from the present condition of the mind, that it may live here-
after without any commerce with its body.
The incomparable mathematician Vietus, who first restored algebra
to us, received the enemies' letters from the king, to expound their
mystical signs ; while he was studying to explain their meaning, he was
taken up with the most profound meditation for three whole days and
nights, insomuch that he was not sensible of what had been trans-
acted without his knowledge, taking no more concern of his body, than
if it had been long deserted as an enemy by his mind. In like manner,
we find Archimedes in a consternation when he first was ordered to
answer King Hiero concerning the mixed gold in the crown till at
last lighting upon the experiment, i. e., going into the bath, he cried
out victory. And in the same manner a Roman, who was in a deep
consternation of ecstasy, being not at all terrified at the advances of the
Syracutians in battle, made a great conquest without once breaking
his lines.
The life of the body is, i. To generate motion under particular
circumstances, as the loadstone approaches to iron. 2. For its con-
stituent parts to attract each other, from whence proceeds the resist-
ance to the force of external bodies, or vis inertia. 3. To gravitate, or
tend towards the center of its planet. And then, 4, comes the affections
proper to particular bodies. The life of the mind is, I. To perceive
the appearances of all external objects, by the changes they make in
the organs of sensation. 2. To judge or compare the nature of two
ideas with each other, and then to deduce some consequences, as that
they are of the same kind, or different ; as we conclude from the notions
of a circle and triangle, that a triangle is not a circle. 3. To will any-
thing. In a word, the life of the mind is to be conscious. These are all
the functions of the mind ; for past actions are uncertain, and they may
be all referred to the single act of its consciousness.
The action of the body is to communicate motion to other bodies ;
the passions of it is to receive some change in itself from another body
or a mind. The action of the mind is volition, which everybody is
acquainted with, but no one can explain. The passions of the mind are
the changes it receives from external objects by the senses. Suppose
the mind to be thinking of a circle, and in the interim a cannon to go
off, it will lose the idea of a circle, and acquire that of sound ; this is
the sufferance of the mind, because it can neither retain the idea of a
circle, nor resist that of sound. There are also some affections in the
246 EIGHTEENTH CENTURY SCIENCE
mind different from the preceding, such as violent passions, or invol-
untary commotions, which the mind cannot resist, and the faculty by
which it moves and determines the several parts of the human body,
agreeable to its inclination.
We cannot understand why two principles, which have no agree-
ment in power, should thus concur in the same functions, though there
have been three hypotheses framed to explain the intercourse of the
body and mind ; the first is, by the physical influx, which supposes the
thing thought of, and the thought itself, to be one and the same ; which
we shall hereafter demonstrate to be absurd, inasmuch as our mind is
ignorant of its own nature. The second is the system of occasional
causes; and the third supposes a harmony established by God, taking
it for an infallible rule, that determinate actions of the mind must be
necessarily attended with corresponding motions in the body, and the
contrary ; and this last seems to be the truest opinion, but it leaves us
equally in the dark with the other.
If any action is to be explained which is compounded both of the
faculties of the mind as well as of the body, such as walking, pain,
voluntary respiration, etc., a just account ought to be first given how
far, and in what manner, the body is concerned in the action, and then
also of the mind ; if this can be done, it is enough, without diving into
the manner of connexion between the different actions; the explica-
tion of the corporeal actions appertains to the physician, and those of
the mind to the philosopher; but their connexion can be explained by
no man. Heat may be conceived to arise in bodies without any rela-
tion to a' thinking mind, as millstones grow hot in their grinding ; but
motion is not explicable from the affections of the body, nor even from
the properties of the mind ; therefore heat and motion are not account-
able from the mind ; and if you should say that the voluntary motions
of the muscles proceed from the act of volition in the mind, you
explain the thing not in the least, because there is nothing in the idea of
motion which is also to be found in any affection of the mind. We call
an explanation of a thing the demonstration of agreement or relation
between its own properties and the same in another ; but this is here not
only impossible, but also quite useless to a physician; for the great
business of a physician is to be acquainted with the means of restoring
lost health, and no cure can be affected by him, but through some
change made in the human body by the application of others; there-
fore this search after the connexion between the body and mind not
EIGHTEENTH CENTURY SCIENCE 247
appertaining to a physician, is to be rejected, among those which are
useless to the art. The physician, who cures diseases of the body, is
not solicitous about those of the mind ; for when the first is set to rights,
the latter will quickly return to its office. Thus when the eye is blinded
with a cataract, the mind cannot perceive sensible objects by it, the
aid of physic is therefore called in to couch the cataract, or depress the
opaque crystalline lens; after which the rays of light finding free
admission to the retina, the mind will be sensible of visible objects by
it ; and thus the business of physic will be done without the assistance
of optics. When a person is in a delirium, or swoon, the physician
cannot recall the mind, which has no relation to his business; but by
applying vinegar, or other volatiles to the nose, he can restore the sick
machine to its former motions, and then the mind will also exhibit its
former actions, and this full as well as if he understood the manner of
connexion between the actions of the body and tnose of the conscious
mind.
LINN/EUS
CARL VON LINNE (CAROLUS LINNAEUS) was born May 13 (o. s.),
1707, at Rashult in Smaland, Sweden. He showed interest in plants
when only about four years old, and continued in this passion to the
neglect of the then more valued scholastic studies. His clergyman
father was about to take him from school, but Dr. Rothman averted the
crisis by urging Carl's father to fit him for medicine. In 1727 Carl
went to the university (at Lund) as the private pupil of his former
preceptor Hoek. At Lund he found a friend in Stobseus.
In 1728 he changed over to Upsala, and was there brought to the
verge of starvation before he found another patron in Celsius. In 1732
he explored Lapland at the expense of the Academy of Sciences. In
1735 Linnaeus fell in love with the daughter of Dr. Moraeus, and left
Sweden to seek his fortune.
He showed his manuscripts of the "Systema Natura" to Gronovius,
who was so taken with it as to publish it at his own expense. The new
system of classification was based on the sex system in plants, and
248 EIGHTEENTH CENTURY SCIENCE
Linnaeus is one of the chief developers of the sex theory. After visit-
ing many of the noted professors of Europe, Linnaeus returned to
Stockholm in 1738. In 1739 he married Sarah Moraeus, and as he was
the next year elected professor in Upsala, his life was henceforth une-
ventful and happy, devoted to his family and the extension of his sys-
tem of botany. He died in 1778. He had found botany a chaos and left
it a unity.
A DISSERTATION ON THE SEXES OF PLANTS
Although the earliest observers of nature could not possibly be
ignorant of the sexes of plants, it has been left for the philosophers of
the present age to demonstrate them. And so abundant are the proofs
of this phenomenon that not a single vegetable can be found which does
not offer them to our consideration.
The Atabaians, from time immemorial, have derived their princi-
pal sustenance from the Phoenix, or Date-bearing Palm, the Persians
from the Turpentine Tree, and the inhabitants of the Archipelago from
the Fig, the people of Chios have likewise cultivated Mastich from the
most remote ages. As it has all along been the practice of these nations
to promote the action of the male trees on the female by the same
means which they use at this day, they must certainly have been ac-
quainted with the sexual difference in plants, upon which the suc-
cess of this practice depends. It is altogether impossible that they
should have been ignorant of a circumstance, which, in these trees at
least is so apparent. If, however, we duly consider the fate of botanical
science, we shall soon see why the doctrine in question has not been
long ago universally understood and received.
The writings of the ancients show that botany had by no means
made great progress among them, at the time when mathematics and
astronomy had risen to a very high degree of perfection. The works of
Theophrastus, Dioscorides, and Pliny, those repositories of ancient
learning, have no pretensions to philosophy in this kind of study, not-
withstanding the assiduity of Dioscorides in seeking out the uses of
plants, and the industry of the writers on husbandry, especially among
the Romans, in the advancement of agriculture. After the revival of
literature, the first employment of botanists was to rescue from total
destruction and oblivion the ruins of ancient erudition ; but after some
time, not finding their acquisitions pay for the labour spent in the search,
EIGHTEENTH CENTURY SCIENCE 2i9
they began to turn their attention to nature herself, and to describe
plants from their observations, till they became so overwhelmed with the
multitude of species, as almost to despair of finding the way in or out of
their gardens ; both the Indies daily furnishing them with so many nov-
elties, that no memory was strong enough to retain them. At length
systematic writers undertook to describe every plant according to its
fructification, by this means to distinguish them from each other, and
arrange them in a methodical manner ; which undertaking has employed
them to the present day. But as these very authors bestowed their chief
attention upon the corolla and the fruit, the former because its beauty
attracts the eye, and the latter because most remarkable for its use, it so
happened that they did not take time to duly consider the minuter parts
of the flower, till they found the larger quite insufficient to discriminate
the immense numbers of vegetables, which were daily augmenting the
catalogue of Flora. The later botanists have therefore been obliged to
examine attentively everything that they were able to discover in the
fructification, in order to find there certain and convenient marks of
distinction. Among these parts, the stamina and pistilla, although gen-
erally very minute bodies, and on that account contemptuously neglected
by former observers, were found so essential, that no flower could be
discovered destitute of them. Hence these organs have ever since been
reckoned of great moment, have obtained particular names, and their
different parts have also been enumerated.
To say precisely who first discovered the sexes of plants, would be
a work of the greatest difficulty, and of no kind of use. Many discov-
eries have proceeded gradually towards perfection, as rivers, although
small and insignificant at their origin, by the addition of fresh streams
in their course, become able at length to bear ships of the greatest bur-
den. It cannot be denied, that the ancient cultivators of Palms, Figs,
and Pistacia, were acquainted with this fact, at least in those trees, for
they knew the necessity of suspending the male flowers over the female,
in order to obtain fruit. Nor is it less certain, that the oldest writers
have expressly mentioned the sexes of plants. But how little real
knowledge of the matter they possessed, and on what slight grounds
they held it, appears from their having frequently described plants as
being severally male and female, which were not so. Nay, after the
revival of literature, even in the last century, botanists retained so much
of the ignorance of former times, that the most eminent teachers of the
science, attempting to discriminate the sexes, very often called the
V 6-16
250 EIGHTEENTH CENTURY SCIENCE
female plant the male; which affords the most decisive proof of their
ignorance that could possibly have been given.
Sir Thomas Millington, an Englishman, is handed down to us, by
his countrymen, as the first discoverer of this doctrine, if he be entitled
to the honor of a discovery, who left no information in writing of what
he had observed. It is pretended that he was perfectly acquainted with
the fact about the year 1676 ; and indeed, a very little while after him,
Grew and Ray, both Englishmen, appear to have gone a good way in the
discovery. Rud. Jac. Camerarius, and other authors, have explained a
great number of particulars, but no one has done more than Vaillant,
the great French botanist, who in an academical oration, published by
Boerhaave, discovers an accurate knowledge of the fact, although he
has not demonstrated it by arguments.
From that time, that is, from the year 1718, many have laboured to
promote this opinion, especially the author of the Sexual System, who
believes he has, in a number of different publications, clearly and decis-
ively established the truth of it ; although Pontedera has endeavored to
refute him, and Alston has even, very lately, treated him with derision.
That the subject may be properly understood, it is in the first place
necessary that we should accurately understand the nature of vegetable
bodies.
The organs common in general to all plants are: ist, The root,
with its capillary vessels, extracting nourishment from the ground. 2nd.
The leaves, which may be called the limbs, and which, like the feet and
wings of animals, are organs of motion; for being themselves shaken
by the external air, they shake and exercise the plant. 3rd. The trunk,
containing the medullary substance, which is nourished by the bark, and
for the most part multiplied into several compound plants. 4th. The
fructification, which is the true body of the plant, set at liberty by a
metamorphosis, and consists only of the organs of generation ; it is often
defended by a calyx, and furnished with petals, by means of which it in
a manner flutters in the air.
Many flowers have no calyx, as several of the lily tribe, the Hip-
puris, etc., many want the corolla, as grasses, and the plants called apet-
alous; but there are none more destitute of stamina and pistilla, those
important organs destined to the formation of fruit. We therefore
infer from experience that the stamina are the male organs of genera-
tion, and the pistilla of the female ; and as many flowers are furnished
EIGHTEENTH CENTURY SCIENCE 251
with both at once, it follows that such flowers are hermaphrodites. Nor
is this so wonderful, as that there should be any plants in which the
different sexes are distinct individuals ; for plants being immovably fixed
to one spot, cannot like animals, travel in search of a mate. There
exists, however, in some plants a real difference of sex. From seeds of
the same mother, some individuals shall be produced, whose flowers
exhibit stamina without pistilla, and may therefore properly be called
male; while the rest being furnished with pistilla without stamina are
therefore denominated females ; and so uniformly does this take place,
that no vegetable was ever found to produce female flowers without
flowers furnished with stamina being produced, either on the same indi-
vidual or on another plant of the same species, and vice versa.
As all seed vessels are destined to produce seeds, so are the stamina
to bear the pollen, or fecundating powder. All seeds contain within
their membranes a certain medullary substance, which swells when
dipped into warm water. All pollen, likewise, contains in its mem-
brane an elastic substance, which, although very subtle, and almost
invisible, by means of warm water often explodes with great vehemence.
While plants are in flower, the pollen falls from their antherae, and is
dispersed abroad, as seeds are dislodged from their situation when the
fruit is ripe. At the same time that the pollen is scattered, the pistillum
presents its stigma, which is then in its highest vigour, and, for a por-
tion of the day at least, it moistened with a fine dew. The stamina either
surround this stigma, or if the flowers are of the drooping kind, they
are bent towards one side, so that the pollen can easily find access to the
stigma, where it not only adheres by means of the dew of that part, but
the moisture occasions its bursting, by which means its contents are dis-
charged. That issued from it being mixed with the fluid of the stigma,
is conveyed to the rudiments of the seed. Many evident instances of this
present themselves to our notice ; but I have nowhere seen it more mani-
fest than in the Jacobean Lily (Amarylis formosissima), the pistillum
of which, when sufficient heat is given the plant to make it flower in per-
fection, is bent downwards and from its stigma issues a drop of limpid
fluid, so large that one would think it in danger of falling to the ground.
It is, however, gradually reabsorbed into the style about three or four
o'clock and becomes invisible until about ten the next morning, when it
appears again ; by noon it attains its largest dimensions ; and in the after-
noon, by a gentle and scarcely perceptible decrease it returns to its
source. If we shake the antherse over the stigma, so that the pollen may
252 EIGHTEENTH CENTURY SCIENCE
fall on this limpid drop, we see the fluid soon after become turbid and
assume a yellow color ; and we perceive little rivulets, or opaque streaks
running from the stigma towards the rudiments of the seed. Some time
afterwards, when the drop has totally disappeared, the pollen may be
observed adhering to the stigma, but of an irregular figure, having lost
its original form. No one, therefore, can assent to what Morland and
others have asserted, that the pollen passes into the stigma, pervades
the style and enters the tender rudiments of the seed, as Leeuwenhoeck
supposed his worms to enter the ova. A most evident proof of the false-
hood of this opinion may be obtained from any species of Mirabilis
(Marvel of Peru), whose pollen is so very large that it almost exceeds
the style itself in thickness, and, falling on the stigma, adheres firmly to
it ; that organ sucking and exhausting the pollen, as a cuttle fish devours
everything that comes within its grasp. One evening in the month of
August, I removed all the stamina from three flowers of the Mirabilis
longiflora, at the same time destroying all the rest of the flowers which
were expanded ; I sprinkled these, three flowers with the pollen of Mira-
bilis Jalappa ; the seed-buds swelled, but did not ripen. Another even-
ing I performed a similar experiment, only sprinkling the flowers with
the pollen of the same species ; all these flowers produced ripe seeds.
Some writers have believed that the stamina are parts of the fructifi-
cation, which serve only to discharge an impure or excrementitious mat-
ter, and by no means formed for so important a work as generation.
But it is very evident that these authors have not sufficiently examined
the subject; for, as in many vegetables, some flowers are furnished with
stamina only, and others only with pistilla; it is altogether impossible
that stamina situated at so very great a distance from the fruit, as on a
different branch, or perhaps on a separate plant, should serve to convey
any impurities from the embryo.
No physiologist could demonstrate, a priori, the necessity of the
masculine fluid to the rendering the eggs of animals prolific, but experi-
ence has established it beyond a doubt. We therefore judge a posteriori
principally, of the same effect in plants.
In the month of January, 1760, the Antholyza Cunonia flowered in
a pot in my parlour, but produced no fruit, the air of the room not being
sufficiently agitated to waft the pollen to the stigma. One day, about
noon, feeling the stigma very moist, I plucked off one of the antherae, by
means of a fine pair of forceps, and gently rubbed it on one part of the
expanded stigmata. The spike of flowers remained eight or ten days
EIGHTEENTH CENTURY SCIENCE 253
longer ; when I observed, in gathering the branch for my herbarium,
that the fruit of that flower only on which the experiment had been
made, had swelled to the size of a bean. I then dissected this fruit and
discovered that one of the three cells contained seeds in considerable
number, the other two being entirely withered.
In the month of April I sowed the seeds of hemp (Canndbis) in two
different pots. The young plants came up so plentifully, that each pot
contained thirty or forty. I placed each by the light of a window, but in
different and remote apartments. The hemp grew extremely well in
both pots. In one of them I permitted the male and female plants to
remain together, to flower and bear fruit, which ripened in July, being
macerated in water, and committed to the earth, sprung up in twelve
days. From the other, however, I removed all the male plants, as soon
as they were old enough for me to distinguish them from the females.
The remaining females grew very well, and presented their long pis-
tilla in great abundance, these flowers continuing a very long time, as if
in expectation of their mates ; whiltf the plants in the other pot had
already ripened their fruit, their pistilla having, quite in a different
manner, faded as soon as the males had discharged all their pollen. It
was truly a beautiful and truly admirable spectacle to see the unimpreg-
nated females preserve their pistilla so long green and flourishing, not
permitting them to begin to fade till they had been for a very consider-
able time exposed in vain, to the access of the male pollen.
Afterwards, when these virgin plants began to decay through age,
I examined all their calyces in the presence of several botanists and
found them large and flourishing, although every one of the seed-buds
was brown, compressed, membranaceous, and dry, not exhibiting any
appearance of cotyledons or pulp. Hence I am perfectly convinced that
the circumstance which authors have recorded, of the female hemp hav-
ing produced seeds, although deprived of the male, could only have hap-
pened by means of pollen brought by the wind from some distant place.
No experiment can be more easily performed than the above ; none more
satisfactory in demonstrating the generation of plants.
The Clutia tenella was in like manner kept growing in my window
during the months of June and July. The male plant was in one pot,
the female in another. The latter abounded with fruit, not one of its
flowers proving abortive. I removed the two pots into different win-
dows of the same apartment ; still all the female flowers continued to be-
come fruitful. At length I took away the male entirely, leaving the
254 EIGHTEENTH CENTURY SCIENCE
female alone, and tutting off all the flowers which it had already borne.
Every day new ones appeared from the axila of every leaf; each
remained eight or ten days, after which their foot stalks turning yellow,
they fell barren to the ground. A botanical friend, who had amused
himself with observing this phenomenon with me, persuaded me to
bring, from the stove in the garden, a single male flower, which he
placed over one of the female ones, then in perfection, tying a piece of
red silk around its pistillum. The next day the male flower was taken
away, and this single seed-bud remained, and bore fruit. Afterwards I
took another male flower out of the same stove, and with a pair of slen-
der forceps pinched off one of its antherae, which I afterwards gently
scratched with a feather, so that a very small portion of its pollen was
discharged upon one of the three stigmata of a female flower, the
other two stigmata being covered with paper. This fruit likewise at-
tained its due size, and on being cut transversely, exhibited one cell
filled with a large seed, and the other two empty. The rest of the flow-
ers, being unimpregnated, faded and fell off. This experiment may be
performed with as little trouble as the former.
The Datifca canndbina came up in my garden from seed ten years
ago, and has every year been plentifully increased by means of its
perennial root. Flowers in great number have been produced by it ; but,
being all female, they proved abortive. Being desirous of producing
male plants, I obtained more seeds from Paris. Some more plants were
raised ; but these likewise to my great mortification, all proved females,
and bore flowers, but no fruit. In the year 1757 I received another par-
cel of seeds. From these I obtained a few male plants, which flowered
in 1758. These were planted at a great distance from the females ; and
when their flowers were just ready to emit their pollen, holding a paper
under them, I gently shook the spike of panicle with my finger, till the
paper was almost covered with the yellow powder. I carried this to the
females, which were flowering in another part of the garden, and placed
it over them. The cold nights of the year in which this experiment was
made, destroyed these Datifcas, with many other plants, much earlier
than usual. Nevertheless, when I examined the flowers of those plants,
which I had sprinkled with the fertilizing powder, I found the seeds of
their due magnitude ; while in the more remote Datifcas, which had not
been impregnated with pollen, no traces of seeds were visible.
Several species of Momordica, cultivated by us, like other Indian
vegetables, in close stoves, have frequently borne female flowers ; which,
EIGHTEENTH CENTURY SCIENCE 255
although at first very vigorous, after a short time have constantly faded
and turned yellow, without perfecting any seed, till I instructed the gar-
dener, as soon as he observed a female flower, to gather a male one, and
place it above the female. By this contrivance we are so certain of
obtaining fruit that we dare pledge ourselves to make any female flow-
ers fertile that shall be fixed on.
The Jatropha urens has flowered every year in my hot-house ; but
the female flowers coming before the males, in a week's time dropped
their petals and faded before the latter were opened ; from which cause
no fruit has been produced, but the germina themselves have fallen off.
We have therefore never had any fruit of the Jatropha till the year 1752,
when the male flowers were in vigour on a tall tree, at the same time
that the females began to appear on a small Jatropha which was growing
in a garden-pot. I placed this pot under the other tree, by which means
the female flowers bore seeds, which grew in being sown. I have fre-
quently amused myself with taking the male flowers from one plant, and
scattering them over the female flowers of another, and have always
found the seeds of the latter impregnated by it.
Two years ago I placed a piece of paper under some of these male
flowers and afterwards folded up the pollen which had fallen upon it,
preserving it so folded up, if I remember right, four or six weeks, at the
end of which time another branch of the same Jatropha was in flower. I
then took the pollen, which I had so long preserved in paper, and
strewed it over three female flowers, the only ones at that time expanded.
These three females proved fruitful, while all the rest, which grew in
the same bunch, fell off abortive.
The interior petals of the Ornithogalum, commonly, but improp-
erly called Canadense, cohere so closely together that they only just
admit the air to the germen and will scarcely permit the pollen of another
flower to pass ; this plant produced every day new flowers and fruit, the
fructification never failing in any instance ; I therefore, with the utmost
care, extracted the antherse from one of the flowers with a hooked
needle, and as I hoped, this single flower proved barren. This experi-
ment was repeated about a week after with the same success.
I removed all of the antherse out of a flower of Chelidonium cornic-
ulatum (scarlet-horned poppy), which was growing in a remote part of
the garden, upon the first opening of its petals, and stripped off all the
rest of the flowers ; another day I treated another flower of the same
plant in a similar manner, but sprinkled the pistillum of this with the
256 EIGHTEENTH CENTURY SCIENCF
pollen borrowed from another plant of the same species ; the result was,
that the first flower produced no fruit, but the second afforded very per-
fect seed. My design in this experiment was to prove that the mere
removal of the antherae from a flower is not in itself sufficient to render
the germen abortive.
Having the Nlcotiana fruticosa growing in a garden-pot, and pro-
ducing plenty of flowers and seed, I extracted the antherae from the
newly expanded flowers before they had burst, at the same time cutting
away all the other flowers; this germen produced no fruit, nor did it
even swell.
I removed an urn, in which the Asphodelus fistulosus was grow-
ing, to one corner of the garden, and from one of the flowers which had
lately opened, I extracted its antherse; this caused the impregnation to
fail. Another day I treated another flower in the same manner; but,
bringing a flower from a plant in a different part of the garden, with
which I sprinkled the pistillum of the mutilated one, its germen became
by that means fruitful.
Ixla chinensis, flowering in my stove, the windows of which were
shut, all its flowers proved abortive. I therefore took one of its anthers
in a pair of pincers, and with them sprinkled the stigmata of two flow-
ers, and the next day one stigma only of a third flower ; the seed-buds of
these flowers remained, grew to a large size and bore seed, the fruit of
the third, however, contained ripe seed only in one of its cells.
To relate more experiments would only be to fatigue the reader
unnecessarily. All nature proclaims the truth I have endeavored to
inculcate, and every flower bears witness to it. Any person may make
the experiment for himself with any plant he pleases, only taking care to
place the pot in which it is growing, in the window of a room suffi-
ciently out of reach of other flowers ; and I will venture to promise him
that he will obtain no perfect fruit unless pollen has access to the pis-
tillum.
Logan's experiments on the Mays are perfectly satisfactory, and
manifestly show that the pollen does not enter the style, or arrive at the
germen, but that it is exhausted by the genital fluid of the pistillum. And
as in animals no conception can take place, unless the genital fluid of the
female be discharged at the same moment as the impregnating liquor of
the male ; so in plants, generation fails, unless the stigma be moist with
prolific dew.
Husbandmen know, by long experience, that if rain falls while rye
EIGHTEENTH CENTURY SCIENCE 257
is in flower, by coagulating the pollen of its antherae, it occasions the
emptiness of many husks in the ear.
Gardeners remark the same thing every year in fruit trees. Their
blossoms produce no fruit if they have unfortunately been exposed to
long-continued rains.
Aquatic plants rise above the water at the time of flowering, and
afterwards again subside, for no other reason, than that the pollen may
safely reach the stigma.
The white water-lily (Nymphaea alba) raises itself every morning
out of the water and opens its flowers, so that by noon at least three
inches of its flower-stalk may be seen above the surface. In the evening
it is closely shut up, and withdrawn again ; for about four o'clock in the
afternoon the flower closes, and remains all night under water; which
was observed full two thousand years since, even as long ago as the
time of Theophrastus, who has described this circumstance in the
Nymphaea Lotus, a plant so much resembling our white water-lily that
they are only distinguished from each other by the leaves of the Lotus
being indented. Theophrastus gives the following account of this vege-
table, in his History of Plants, book IV.; chap. 10 : "It is said to with-
draw its flowers into the Euphrates, which continue to descend till
midnight, to so great a depth that at daybreak they are out of reach of
the hand ; after which it rises again, and in the course of the morning
appears above the water, and expands its flowers, rising higher and
higher, till it is a considerable height above the surface." The very
same thing may be observed in the Nymphaea alba.
Many flowers close themselves in the evening and before rain, lest
the pollen should be coagulated; but after the discharge of the pollen
they always remain open. Such of them as do not shut up, incline their
flowers downward in those circumstances, and several flowers, which
come forth in the moisture of spring, droop perpetually. The manner
in which the Parnassia and Saxigrage move their antherae to the stigma
is well known. The common Rue, a plant everywhere to be met with,
moves one of its antherse every day to the stigma, till all of them in their
turns have deposited their pollen there.
The Neapolitan star flower (ornithogalum nutans) has six broad
stamina, which stand close together in the form of a bell, the three
external ones being but half the length of the others ; so that it seems
impossible for their antherse ever to convey their pollen to the stigma ;
but nature, by an admirable contrivance, bends the summits of these
258 EIGHTEENTH CENTURY SCIENCE
external stamina inwards between the other filaments, so that they are
enabled to accomplish their purpose.
The Plaintain tree (Musa) bears two kinds of hermaphrodite flow-
ers; some have imperfect antherae, others only the rudiments of stig-
mata; as the last mentioned kind appear after the others, they cannot
impregnate them, consequently no seeds are produced in our gardens,
and scarcely ever on the plants cultivated in India. An event happened
this year, which I have long wished for; two plaintain-trees flowering
with me so fortunately that one of them brought forth its first female
blossoms at the time that male ones began to appear on the other. I
eagerly ran to collect antherae from the first plant, in order to scatter
them over the newly-expanded females, in hopes of obtaining seed from
them, which no botanist has yet been able to do. But when I came to
examine the antherae I found even the largest of them absolutely empty
and void of pollen, consequently unfit for impregnating the females ; the
seeds of this plant, therefore, can never be perfected in our gardens. I
do not doubt, however, that real male plants of this species may be found
in its native country, bearing flowers without fruit, which the gardeners
have neglected; while the females in this country produce imperfect
fruit, without seeds, like the female fig ; and, like that tree, are increased
easily by suckers. The fruit, therefore, of the plaintain-tree scarcely
attains anything like its due size, the larger seed-buds only ripening,
without containing anything in them.
The day would sooner fail me than examples. A female date-bear-
ing palm flowered many years at Berlin, without producing any seeds.
But the Berlin people taking care to have some of the blossoms of the
male tree, which was then flowering at Leipsic, sent them by the post,
they obtained fruit by that means ; and some dates, the offspring of this
impregnation, being planted in my garden, sprung up, and to this day
continue to grow vigorously. Kcempfer formerly told us how neces-
sary it was found by the oriental people, who live upon the produce of
palm-trees, and are the true Lotophagi, to plant some male trees among
the females, if they hoped for any fruit ; hence, it is the practice of those
who make war in that part of the world to cut down all the male palms,
that a famine may afflict their proprietors ; sometimes even the inhab-
itants themselves destroy the male trees, when they dread an invasion,
that their enemies may find no sustenance in the country.
Leaving these instances, and innumerable others, which are so well
known to botanists that they would by no means bear the appearance of
EIGHTEENTH CENTURY SCIENCE 253
novelty, and can only be doubted by those persons who neither have
observed nature, nor will they take the trouble to study her, I pass to a
fresh subject, concerning which much new light is wanted; I mean
hybrid, or mule vegetables, the existence and origin of which we shall
now consider.
I shall enumerate three or four real mule plants, to whose origin I
have been an eye-witness.
1. Veronica spuria, described in Amoenitates Acad. vol. III. p. 35,
came from the impregnation of Veronic maratima by Verbena officin-
alis; it is easily propagated by cuttings, and agrees perfectly with its
mother in fructification, and with its father in leaves.
2. Delphinium hybridum, sprung up in a part of the garden where
Delphinium datum and Aconitum Napellus grew together ; it resembles
its mother as much in its internal parts, that is, in fructification as it does
its father (the Aconitum) in outward structure, or leaves; and, owing
its origin to plants so nearly allied to each other, it propagates itself by
seed ; some of which I now send with this Dissertation.
3. Hieracium Taraxici, gathered in 1753 upon our mountains by
Dr. Solander, in its thick, brown, woolly calyx ; in its stem being hairy
towards the top, and in its bractese, as well as in every parts of its fructi-
fication, resembles so perfectly its mother, Hieracium alpinum, that an
inexperienced person might mistake one for the other; but in the
smoothness of its leaves, in their indentations and whole structure, it so
manifestly agrees with its father, Leontodon Taraxacum (Dandelion),
that there can be no doubt of its origin.
4. Tragopogon hybridum attracted my notice the autumn before
last, in a part of the garden where I had planted Tragopogon pratense,
and Tragopogon porrifolium ; but winter coming on, destroyed its seeds.
Last year, while the Tragopogon pratense was in flower I rubbed off its
pollen early in the morning, and about eight o'clock sprinkled its stig-
mata with some pollen of the Tragopogon porrifolium, marking the
calyces by tying a thread round them. I afterwards gathered the seeds
when ripe, and sowed them that autumn in another place; they grew,
and produced this year, 1759, purple flowers yellow at the base, seeds of
which I now send. I doubt whether any experiment demonstrates the
generation of plants more certainly than this.
There can be no doubt that these are all new species produced by
hybrid generation. And hence we learn, that a mule offspring is the
exact image of its mother in its medullary substance, internal nature, or
260 EIGHTEENTH CENTURY SCIENCE
fructification, but resembles its father in leaves. This is a foundation
upon which naturalists may build much. For it seems probable that
many plants, which now appear different species of the same genus, may
in the beginning have been but one plant, having arisen merely from
hybrid generation. Many of those Geraniums which grow at the Cape of
Good Hope, and have never been found wild anywhere but in the south
parts of Africa, and which, as they are distinguished from all other
Geraniums by their single-leaved calyx, many-flowered foot-stalk, irreg-
ular corolla, seven fertile stamina, and three mutilated ones, and by
their naked seeds furnished with downy awns ; so they agree together in
all these characters, although very various in their roots, stems and
leaves ; these Geraniums, I say, would almost induce a botanist to believe
that the species of one genus in vegetables are only so many different
plants as there have been different associations with the flowers of one
species, and consequently a genus is nothing else than a number of
plants sprung from the same mother by different fathers. But whether
all these species be the offspring of time ; whether, in the beginning of all
things, the Creator limited the number of future species, I dare not pre-
sume to determine. I am, however, convinced this mode of multiplying
plants does not interfere with the system or general scheme of nature ;
as I daily observe that insects, which live upon one species of a particu-
lar genus, are contented with another of the same genus.
A person who has once seen the Achyranthes aspera, and remarked
its spike, the parts of its flower, its small and peculiarly formed nec-
taria, as well as its calyces bent backwards as the fruit ripens, would
think it very easy at any time to distinguish these flowers from all others
in the universe; but when he finds the flowers of Achyranthes indica
agreeing with them even in their minutest parts, and at the same time
observes the large, thick, obtuse, undulated leaves of the last-mentioned
plant, he will think he sees Achyranthes aspera masked in the foliage of
Xanthium strumarium. But I forbear to mention any more instances.
Here is a new employment for botanists, to attempt the production
of new species of vegetables by scattering the pollen of various plants
over various widowed females. And if these remarks should meet with
a favourable reception, I shall be the more induced to dedicate what
remains of my life to such experiments, which recommend themselves by
being at the same time agreeable and useful. I am persuaded by many
considerations that those numerous and most valuable varieties of plants
which are used for culinary purposes, have been produced in this man-
EIGHTEENTH CENTURY SCIENCE 261
ner, as the several kinds of cabbages, lettuces, etc. ; and I apprehend this
is the reason of their not being changed by a difference of soil. Hence I
cannot give my assent to the opinion of those who imagine all varieties
to have been occasioned by change of soil ; for, if this were the case, the
plants would return to their original form, if removed again to their
original situation.
FRANKLIN
BENJAMIN FRANKLIN was born in Boston, January 6, 1706. How he
ran away from his brother to whom he was apprenticed, how he strug-
gled at his printer's trade in Philadelphia, London and again in Phil-
adelphia, until he finally reached success, ought to be familiar to all from
his autobiography. His paper, the Gazette, became probably the best of
the colonial sheets, and his Poor Richard's Almanac, first published in
1732, made him famous on two continents. A police force, city care of
the streets, fire companies, a public library, a city academy, all of these
movements in Philadelphia owed their origin to him. Later he brought
about the establishment of postorEces and post roads. In 1746 he began
making his experiments in electricity which reached their climax in his
identification of electricity with lightning. The immense significance of
this experiment was to show the infinite power of electricity.
From 1757 to 1762 he was in London as spokesman of the assem-
bly ©n the question of the Penn estates in the colony being taxed.
In 1764 he returned to London as representative of the colonists
against the stamp duty and taxation without representation. When in
1775 he again arrived in Philadelphia he was at once sent as a delegate
to the Continental congress, and after the Declaration of Independence
was signed, was dispatched to France as a commissioner of the colonies.
To him more than any one man was due the aid given by France.
He was in France until 1783. In 1787 he was made a member of
the convention to frame a new constitution, and did much to further its
construction.
He died in 1790, great as a journalist and writer, as a scientist, a
statesman, a diplomat, and a man of affairs.
5462 EIGHTEENTH CENTURY SCIENCE
TO PETER COLLINSON
Wonderful 'Effect of Points — Positive and Negative Electricity — Elec-
trical Kiss — Counterfeit Spider — Simple and Commodious Elec-
trical Machine.
Philadelphia, II July, 1747.
SIR,
In my last I informed you that, in pursuing our electrical inquiries,
we had observed some particular phenomena, which we looked upon to
be new, and of which I promised to give you some account, although I
apprehended they might not possibly be new to you, as so many hands
are daily employed in electrical experiments on your side of the water,
some or other of which would probably hit on the same observations.
The first is the wonderful effect of pointed bodies, both in drawing
off and throwing off electrical fire. For example :
Place an iron shot, of three or four inches diameter, on the mouth
of a clean, dry glass bottle. By a fine silken thread from the ceiling,
right over the mouth of the bottle, suspend a small cork ball, about the
bigness of a marble; the thread of such a length as that the cork ball
may rest against the side of the shot. Electrify the shot, and the ball
will be repelled to the distance of four or five inches, more or less,
according to the quantity of electricity. When in this state, if you pre-
sent to the shot, the point of a long, slender, sharp bodkin, at six or eight
inches distance, the repellency is instantly destroyed, and the cork flies
to the shot. A blunt body must be brought within an inch, and draw a
spark, to produce the same effect. To prove that the electrical fire is
drawn off by the point, if you take the blade of the bodkin out of the
wooden handle, and fix it in a stick of sealing-wax, and then present it
at the distance aforesaid, or if you bring it very near, no such effect
follows ; but sliding one finger along the wax till you touch the blade,
and the ball flies to the shot immediately. If you present the point in
the dark, you will see, sometimes at a foot distance and more, a light
gather upon it, like that of a fire-fly, or glow-worm ; the less sharp the
point, the nearer you must bring it to observe the light ; and, at what-
ever distance you see the light, you may draw off the electrical fire and
destroy the repellency. If a cork ball so suspended be repelled by the
tube, and a point be presented quick to it, though at a considerable dis-
EIGHTEENTH CENTURY SCIENCE 263
tance, it is surprising to see how suddenly it flies back to the tube. Points
of wood will do near as well as those of iron, provided the wood is not
dry ; for perfectly dry wood will no more conduct electricity than seal-
ing-wax.
To show that points will throw off as well as draw off the electri-
cal fire ; lay a long, sharp needle upon the shot, and you cannot electrize
the shot so as to make it repel the cork ball. Or fix a needle to the end of
a suspended gun-barrel, or iron rod, so as to point beyond it, like a little
bayonet ; and, while it remains there, the gun-barrel, or rod, cannot by
applying the tube to the other end be electrized so as to give a spark,
the fire continually running out silently at the point. In the dark you
may see it make the same appearance as it does in the case before men-
tioned.
The repellency between the cork ball and the shot is likewise de-
stroyed; 1st, by sifting fine sand on it; this does it gradually; 2dly, by
breathing on it ; 3dly, by making a smoke about it from burning wood ;
4thly, by candle-light, even though the candle is at a foot distance;
these do it suddenly. The light of a bright coal from a wood fire, and
the light of a red-hot iron, do it likewise ; but not at so great a distance.
Smoke, from dry rosin dropped on hot iron, does not destroy the repel-
lency ; but is attracted by both shot and cork ball, forming proportionate
atmospheres round them, making them look beautifully, somewhat like
some of the figures in Burnet's or Whiston's Theory of the Earth.
N. B. This experiment should be made in a closet, where the air
is very still, or it will be apt to fail.
The light of the sun thrown strongly on both cork and shot by a
looking-glass, for a long time together, does not impair the repellency
in the least. This difference between fire-light and sun-light is another
thing that seems new and extraordinary to us.
We had for some time been of the opinion, that the electrical fire
was not created by friction, but collected, being really an element dif-
fused among, and attracted by, other matter, particularly by water and
metals. We had even discovered and demonstrated its afflux to the
electrical sphere, as well as its efflux, by means of little, light windmill
wheels, made of stiff paper vanes, fixed obliquely, and turning freely on
fine wire axes ; also by little wheels, of the same matter, but formed like
water-wheels. Of the disposition and application of which wheels, and
the various phenomena resulting, I could, if I had time, fill you a sheet.
The impossibility of electrizing one's self (though standing on wax) by
264 EIGHTEENTH CENTURY SCIENCE
rubbing the tube, and drawing the fire from it ; and the manner of doing-
it, by passing the tube near a person or thing standing on the floor, &c.,
had also occurred to us some months before Mr. Watson's ingenious
Sequel came to hand ; and these were some of the new things I intended
to have communicated to you. But now I need only mention some par-
ticulars not hinted in that piece, with our reasonings thereupon ; though
perhaps the latter might v/ell enough be spared.
1. A person standing on wax, and rubbing the tube, and another
person on wax drawing the fire, they will both of them (provided they
do not stand so as to touch one another) appear to be electrized, to a
person standing on the floor; that is, he will perceive a spark on ap-
proaching each of them with his knuckle.
2. But if the persons on wax touch one another during the exciting
of the tube, neither of them will appear to be electrized.
3. If they touch one another after exciting the tube and drawing the
fire as aforesaid, there will be a stronger spark between them, than was
between either of them and the person on the floor.
4. After such strong spark neither of them discover any electricity.
These appearances we attempt to account for thus. We suppose,
as aforesaid, that electrical fire is a common element, of which every
one of the three persons above mentioned has his equal share, before any
operation is begun with the tube. A, who stands on wax and rubs the
tube, collects the electrical fire from himself into the glass; and, his
communication with the common stock being cut off by the wax, his
body is not again immediately supplied. B, (who stands on wax like-
wise) passing his knuckle along near the tube, receives the fire which
was collected by the glass from A ; and his communication with the com-
mon stock being likewise cut off, he retains the additional quantity
received. To C, standing on the floor, both appear to be electrized ; for
he, having only the middle quantity of electrical fire, receives a spark
upon approaching B, who has an over-quantity ; but gives one to A, who
has an under-quantity. If A and B approach to touch each other, the
spark is stronger, because the difference between them is greater. After
such touch there is no spark between either of them and C, because the
electrical fire in all is reduced to the original equality. If they touch while
electrizing, the equality is never destroyed, the fire only circulating.
Hence have arisen some new terms among us; we say B (and bodies
like circumstanced) is electrized positively; A, negatively. Or rather
B is electrized plus ; A, minus. And we daily in our experiments elec-
EIGHTEENTH CENTURY SCIENCE 265
trize bodies plus or minus, as we think proper. To electrize plus or
minus, no more needs to be known than this, that the parts of the tube
or sphere that are rubbed, do, in the instant of the friction, attract the
electrical fire, and therefore take it from the thing rubbing; the same
parts immediately, as the friction upon them ceases, are disposed to give
the fire they have received to any body that has less. Thus you may
circulate it, as Mr. Watson has shown ; you may also accumulate or sub-
tract it, upon or from any body, as you connect that body with the rub-
ber, or with the receiver, the communication with the common stock
being cut off. We think that ingenious gentleman was deceived when
he imagined (in his Sequel), that electrical fire came down the wire
from the ceiling to the gun-barrel, thence to the sphere, and so electrized
the machine and the man turning the wheel, &c. We suppose it was
driven off, and not brought on through that wire ; and that the machine
and man, &c., were electrized minus, that is, had less electrical fire in
them than things in common.
As the vessel is just upon sailing, I cannot give you so large an
account of American electricity as I intended ; I shall only mention a
few particulars more. We find granulated lead better to fill the phial
with, than water, being easily warmed, and keeping warm and dry in
damp air. We fire spirits with the wire of the phial. We light candles,
just blown out, by drawing a spark among the smoke, between the wire
and snuffers. We represent lightning, by passing the wire in the dark,
over a China plate, that has gilt flowers, or applying it to gilt frames of
looking-glasses, &c. We electrize a person twenty or more times run-
ning, with a touch of the finger on the wire, thus ; He stands on wax.
Give him the electrized bottle in his hand. Touch the wire with your
finger, and then touch his hand or face; there are sparks every time.
We increase the force of the electrical kiss vastly, thus ; Let A and B
stand on wax ; or A on wax and B on the floor ; give one of them the
electrized phial in his hand ; let the other take hold of the wire ; there
will be a small spark ; but when their lips approach, they will be struck
and shocked. The same, if another gentleman and lady, C and D, stand-
ing also on wax, and joining hands with A and B, salute or shake hands.
We suspend by fine silk thread a counterfeit spider, made of a small
piece of burnt cork, with legs of linen thread, and a grain or two of lead
stuck in him, to give him more weight. Upon the table, over which he
hangs, we stick a wire upright, as high as the phial and wire, four or five
inches from the spider ; then we animate him, by setting the electrified
V 6-17
266 EIGHTEENTH CENTURY SCIENCE
phial at the same distance on the other side of him ; he will immediately
fly to the wire of the phial, bend his legs in touching it, then spring off,
and fly to the wire in the table ; thence again to the wire of the phial,
playing with his legs against both, in a very entertaining manner, ap-
pearing perfectly alive to persons unacquainted. He will continue this
motion an hour or more in dry weather. We electrify, upon wax in the
dark, a book that has a double line of gold round upon the covers, and
then apply a knuckle to the gilding ; the fire appears everywhere upon the
gold like a flash of lightning; not upon the leather, nor if you touch the
leather instead of the gold. We rub our tubes with buckskin, and observe
always to keep the same side to the tube, and never to sully the tube by
handling; thus they work readily and easily, without the least fatigue,
especially if kept in tight pasteboard cases, lined with flannel, and sit-
ting close to the tube. This I mention, because the European papers on
electricity frequently speak of rubbing the tube as a fatiguing exercise.
Our spheres are fixed upon iron axes, which pass through them. At one
end of the axis there is a small handle, with which you turn the sphere
like a common grindstone. This we find very commodious, as the
machine takes up but little room, is portable, and may be enclosed in a
tight box, when not in use. It is true, the sphere does not turn so swift
as when the great wheel is used ; but swiftness we think of little import-
ance, since a few turns will charge the phial, &c., sufficiently.
I am, &c.
B. FRANKLIN.
THE IDENTITY OF LIGHTNING AND ELECTRICITY. THE
LIGHTNING ROD
But points have a property, by which they draw on as well as throw
off the electrical fluid, at greater distances than blunt bodies can. That
is, as the pointed part of an electrified body will discharge the atmo-
sphere of that body, or communicate it farthest to another body, so the
point of an unelectrified body will draw off the electrical atmosphere
from an electrified body, farther than a blunter part of the same unelec-
trified body will do. Thus, a pin held by the head, and the point
presented to an electrified body, will draw off its atmosphere at a foot
distance ; where, if the head were presented instead of the point, no such
effect would follow. To understand this, we may consider, that, if a
EIGHTEENTH CENTURY SCIENCE 267
person standing on the floor would draw off the electrical atmosphere
from an electrified body, an iron crow and a blunt knitting-needle, held
alternately in his hand, and presented for that purpose, do not draw with
different forces in proportion to their different masses. For the man,
and what he holds in his hand, be it large or small, are connected with
the common mass of unelectrified matter ; and the force with which he
draws is the same in both cases, it consisting in the different proportion
of electricity in the electrified body, and that common mass. But the
force, with which the electrified body retains its atmosphere by attracting
it, is proportioned to the surface over which the particles are placed ;
that is, four square inches of that surface retain their atmosphere with
four times the force that one square inch retains its atmosphere. And, as
in plucking the hairs from the horse's tail, a degree of strength not suf-
ficient to pull away a handful at once, could yet easily strip it hair by
hair, so a blunt body presented cannot draw off a number of particles at
once, but a pointed one, with no greater force, takes them away easily,,
particle by particle.
These explanations of the power and operation of points, when they
first occurred to me, and while they first floated in my mind, appeared
perfectly satisfactory; but now I have written them, and considered
them more closely, I must own I have some doubts about them ; yet, as I
have at present nothing better to offer in their stead, I do not cross
them out; for, even a bad solution read, and its faults discovered, has
often given rise to a good one, in the mind of an ingenious reader.
Nor is it of much importance to us to know the manner in which
nature executes her laws ; it is enough if we know the laws themselves.
It is of real use to know that China left in the air unsupported, will fall
and break ; but how it comes to fall, and why it breaks, are matters of
speculation. It is a pleasure indeed to know them, but we can preserve
our China without it.
Thus, in the present case, to know this power of points may pos-
sibly be of some use to mankind, though we should never be able to
explain it. The following experiments, as well as those in my first pa-
per, show this power. I have a large prime conductor, made of several
thin sheets of clothier's pasteboard, formed into a tube, near ten feet
long and a foot diameter. It is covered with Dutch embossed paper,
almost totally gilt. This large metallic surface supports a much greater
electrical atmosphere than a rod of iron of fifty times the weight would
do. It is suspended by silk lines, and when charged will strike, at near
268 EIGHTEENTH CENTURY SCIENCE
two inches distance, a pretty hard stroke, so as to make one's knuckle
ache. Let a person standing on the floor present the point of a needle,
at twelve or more inches distance from it, and while the needle is so
presented, the conductor cannot be charged, the point drawing off the
fire as fast as it is thrown on by the electrical globe. Let it be charged,
and then present the point at the same distance, and it will suddenly be
discharged. In the dark you may see the light on the point, when the
experiment is made. And if the person holding the point stands upon
wax, he will be electrified by receiving the fire at that distance. Attempt
to draw off the electricity with a blunt body, as a bolt of iron round at
the end, and smooth, (a silversmith's iron punch, inch thick, is what I
use,) and you must bring it within the distance of three inches before
you can do it, and then it is done with a stroke and crack. As the
pasteboard tube hangs loose on silk lines, when you approach it with
the punch-iron, it likewise will move towards the punch, being attracted
while it is charged ; but if, at the same instant, a point be presented as
before, it retires again, for the point discharges it. Take a pair of large
brass scales, of two or more feet beam, the cords of the scales being
silk. Suspend the beam by a pack-thread from the ceiling, so that the
bottom of the scales may be about a foot from the floor ; the scales will
move round in a circle by the untwisting of the pack-thread. Set the
iron punch on the end upon the floor, in such a place as that the scales
may pass over it in making their circle ; then electrify one scale by apply-
ing the wire of a charged phial to it. As they move round, you see that
scale draw nigher to the floor, and dip more when it comes over the
punch ; and, if that be placed at a proper distance, the scale will snap and
discharge its fire into it. But, if a needle be stuck on the end of true
punch, its point upward, the scale, instead of drawing nigh to the punch,
and snapping, discharges its fire silently through the point, and rises
higher from the punch. Nay, even if the needle be placed upon the
floor near the punch, its point upwards, the end of the punch, though
so much higher than the needle, will not attract the scale and receive
its fire, for the needle will get it and convey it away, before it comes
nigh enough for the punch to act. And this is constantly observable
in these experiments, that the greater quantity of electricity on the
pasteboard tube, the farther it strikes or discharges its fire, and the
point likewise will draw it off at a still greater distance.
Now if the fire of electricity and that of lightning be the same, as I
have endeavoured to show at large in a former paper, this pasteboard
EIGHTEENTH CENTURY SCIENCE 269
tube and these scales may represent electrified clouds. If a tube of only
ten feet long will strike and discharge its fire on the punch at two or
three inches distance, an electrified cloud of perhaps ten thousand acres
may strike and discharge on the earth at a proportionately greater
distance. The horizontal motion of the scales over the floor, may rep-
resent the motion of the clouds over the earth ; and the erect iron punch,
a hill or high building ; and then we see how electrified clouds passing
over hills or high buildings at too great a height to strike, may be
attracted lower till within their striking distance. And, lastly, if a
needle fixed on the punch with its point upright, or even on the floor
below the punch, will draw the fire from the scale silently at a much
greater than the striking distance, and so prevent its descending towards
the punch ; or if in its course it would have come nigh enough to strike,
yet being first deprived of its fire it cannot, and the punch is thereby
secured from the stroke; I say, if these things are so, may not the
knowledge of this power of points be of use to mankind, in preserving
houses, churches, ships, &c., from the stroke of lightning, by directing us
to fix, on the highest parts of those edifices, upright rods of iron
made sharp as a needle, and gilt to prevent rusting, and from the foot of
those rods a wire down the outside of the building into the ground, or
down round one of the shrouds of a ship, and down her side till it
reaches the water? Would not these pointed rods probably draw the
electrical fire silently out of a cloud before it came nigh enough to
strike, and thereby secure us from that most sudden and terrible mis-
chief ?
To determine the question, whether the clouds that contain light-
ning are electrified or not, I would propose an experiment to be tried
where it may be done conveniently. On the top of some high tower or
steeple, place a kind of sentry-box, (as in Fig. 9,) big enough to contain
a man and an electrical stand. From the middle of the stand let an iron
rod rise and pass bending out of the door, and then upright twenty or
thirty feet, pointed very sharp at the end. If the electrical stand be
kept clean and dry, a man standing on it, when such clouds are passing
low, might be electrified and afford sparks, the rod drawing fire to
him from a cloud. If any danger to the man should be apprehended
(though I think there would be none), let him stand on the floor of his
box, and now and then bring near to the rod the loop of a wire that has
one end fastened to the leads, he holding it by a wax handle; so the
sparks, if the rod is electrified, will strike from the rod to the wire, and
not affect him.
270 EIGHTEENTH CENTURY SCIENCE
THE KITE EXPERIMENT
A history of Franklin's results in electricity was drawn up by Dr.
Stuber, who resided in Philadelphia, and who seems to have written
from minute and accurate information.
"His observations," says Dr. Stuber, "he communicated, in a series
of letters, to his friend Collinson, the first of which is dated March 28th,
1747. In these he shows the power of points in drawing and throwing
off the electrical matter, which had hitherto escaped the notice of elec-
tricians. He also made the grand discovery of a plus and minus, or of a
positive and negative state of electricity. We give him the honor of
this, without hesitation ; although the English have claimed it for their
countryman, Dr. Watson. Watson's paper is dated January 2ist, 1748;
Franklin's July nth, 1747, several months prior. Shortly after, Frank-
lin, from his principles of the plus and minus state, explained, in a sat-
isfactory manner, the phenomena of the Leyden phial, first observed
by Mr. Cuneus, or by Professor Muschenbroeck, of Leyden, which had
much perplexed philosophers. He showed clearly, that, when charged,
the bottle contained no more electricity than before, but that as much
was taken from one side as was thrown on the other ; and that, to dis-
charge it, nothing was necessary but to produce a communication be-
tween the two sides, by which the equilibrium might be restored, and
that then no signs of electricity would remain. He afterwards demon-
strated, by experiments, that the electricity did not reside in the coating,
as had been supposed, but in the pores of the glass itself. After a phial
was charged, he removed the coating, and found that upon applying a
new coating the shock might still be received. In the year 1749, he first
suggested his idea of explaining the phenomena of thunder-gusts, and
of the aurora borealis, upon electrical principles. He points out many
particulars in which lightning and electricity agree; and he adduces
many facts, and reasonings from facts, in support of his positions.
"In the same year, he conceived the astonishingly bold and grand
idea of ascertaining the truth of his doctrine, by actually drawing down
the lightning, by means of sharp-pointed iron rods, raised into the
region of the clouds. Even in this uncertain state, his passion to be
useful to mankind displayed itself in a powerful manner. Admitting the
identity of electricity and lightning, and knowing the power of points in
EIGHTEENTH CENTURY SCIENCE 271
repelling bodies charged with electricity, and in conducting their fire
silently and imperceptibly, he suggested the idea of securing houses,
ships, &c., from being damaged by lightning, by erecting pointed rods,
that should rise some feet above the most elevated part, and descend
some feet into the ground or the water. The effect of these, he con-
cluded, would be either to prevent a stroke by repelling the cloud beyond
the striking distance, or by drawing off the electrical fire which it con-
tained; or, if they could not effect this, they would at least conduct
the electric matter to the earth, without any injury to the building.
"It was not until the summer of 1752, that he was enabled to com-
plete his grand and unparalleled discovery by experiment. The plan
which he had originally proposed was, to erect, on some high tower or
other elevated place, a sentry-box, from which should rise a pointed
iron rod, insulated by being fixed in a cake of resin. Electrified clouds
passing over this would, he conceived, impart to it a portion of their
electricity, which would be rendered evident to the senses by sparks
being emitted, when a key, the knuckle, or other conductor was pre-
sented to it. Philadelphia at this time afforded no opportunity of trying
an experiment of this kind. While Franklin was waiting for the erec-
tion of a spire, it occurred to him that he might have more ready access
to the region of clouds by means of a common kite. He prepared one
by fastening two cross sticks to a silk handkerchief, which would not
suffer so much from the rain as paper. To the upright stick was affixed
an iron point. The string was, as usual, of hemp, except the lower
end, which was silk. Where the hempen string terminated, a key was
fastened. With this apparatus, on the appearance of a thunder-gust
approaching, he went out into the commons, accompanied by his son,
to whom alone he communicated his intentions, well knowing the ridi-
cule, which, too generally for the interest of science, awaits unsuccess-
ful experiments in philosophy. He placed himself under a shed, to avoid
the rain ; his kite was raised, a thunder-cloud passed over it, no sign of
electricity appeared. He almost despaired of success, when suddenly
he observed the loose fibres of his string to move towards an erect posi-
tion. He now presented his knuckle to the key, and received a strong
spark. How exquisite must his sensations have been at this moment!
On this experiment depended the fate of his theory. If he succeeded,
his name would rank high among those who had improved science ; if
he failed, he must inevitably be subjected to the derision of mankind,
or, what is worse, their pity, as a well-meaning man, but a weak, silly
projector. The anxiety, with which he looked for the result of his ex-
272 EIGHTEENTH CENTURY SCIENCE
periment, may be easily conceived. Doubts and despair had begun
to prevail, when the fact was ascertained, in so clear a manner, that even
the most incredulous could no longer withhold their assent. Repeated
sparks were drawn from the key, a phial was charged, a shock given,
and all the experiments made which are usually performed with elec-
tricity/'
BLACK
JOSEPH BLACK was born in 1728 at Bordeaux, France. He was
educated at Belfast and at the University of Glasgow. In 1754 he took
his M. D. degree at Edinburgh.
He had already showed that the alkalies were formed not by their
absorbing the mythical phlogiston, but by having as a component "fixed
air," i. e., carbonic acid gas. This was found out in 1752. In his work
he constantly weighed his materials, thus antedating Lavoisier in the
idea of the permanency of matter. His discovery that there was an air-
like substance that was not air had a wonderful influence.
In 1753 he was made a lecturer on chemistry at Glasgow, and in
1766 succeeded Cullen at Edinburgh.
In 1763 he discovered the principle of latent heat — that heat com-
bines with a substance to change it from a solid to a fluid or from a
liquid to a gas, and that this heat remains inactive — latent — in the new
condition. This principle is the basis of the steam engine, artificial
ice and freezing, and the like, and has been of immense practical im-
portance.
Black died in 1799.
THE DISCOVERY OF CARBONIC ACID GAS, "FIXED AIR"
Hoffman, in one of his observations, gives the history of a powder
called Magnesia Alba, which had been long used, and esteemed as a mild
and tasteless purgative ; but the method of preparing it was not gener-
ally known before he made it public.
EIGHTEENTH CENTURY SCIENCE 273
It was originally obtained from a liquor called the Mother of nitre,
which is produced in the following manner :
Salt-petre is separated from the brine which first affords it, or from
the water with which it is washed out of nitrous earths, by the process
commonly used in crystallizing salts. In this process, the brine is grad-
ually diminished, and at length reduced to a small quantity of an unctu-
ous bitter saline liquor, affording no more salt-petre by evaporation, but,
if urged with a brisk fire, drying up into a confused mass, which attracts
water strongly, and becomes fluid again when exposed to the open air.
To this liquor the workmen have given the name of the Mother of
nitre ; and Hoffman, finding it composed of the magnesia united to an
acid, obtained a separation of these, either by exposing the compound to
a strong fire, in which the acid was dissipated, and the magnesia re-
mained behind, or by the addition of an alkali, which attracted the acid
to itself : and this last method he recommends as the best. He likewise
makes an inquiry into the nature and virtues of the powder thus pre-
pared; and observes, that it is an absorbent earth, which joins readily
with all acids, and must necessarily destroy any acidity it meets in the
stomach ; but that its purgative power is uncertain, for sometimes it has
not the least effect of that kind. As it is a mere insipid earth, he ration-
ally concludes it to be a purgative only when converted into a sort of
neutral salt by an acid in the stomach, and that its effect is therefore
proportional to the quantity of this acid.
Although magnesia appears from this history of it, to be a very in-
nocent medicine ; yet, having observed that some hypochondriacs, who
used it frequently, were subject to flatulencies and spasms, he seems to
have suspected it of some noxious quality. The circumstances, how-
ever, which gave rise to his suspicion, may very possibly have proceeded
from the imprudence of his patients ; who, trusting too much to mag-
nesia (which is properly a palliative in that disease) and neglecting the
assistance of other remedies, allowed their disorder to increase upon
them. It may, indeed, be alleged that magnesia, as a purgative, is
not the most eligible medicine for such constitutions, as they agree best
with those that strengthen, stimulate, and warm; which the saline
purges, commonly used, are not observed to do. But there seems at
least to be no objection to its use, when children are troubled with an
acid in their stomach : for, gentle purging, in this case, is very proper ;
and it is often more conveniently procured by means of magnesia, than
of any other medicine, on account of its being entirely insipid.
The above-mentioned Author, observing, some time after, that a
374 EIGHTEENTH CENTURY SCIENCE
bitter saline liquor, similar to that obtained from the brine of salt-petre,
was likewise produced by the evaporation of those waters which contain
common salt, had the curiosity to try if this would also yield a magnesia.
The experiment succeeded : And he thus found out another process for
obtaining this powder ; and at the same time assured himself, by experi-
ments, that the product from both was exactly the same.
My curiosity led me, some time ago, to inquire more particularly
into the nature of magnesia, and especially to compare its properties with
those of the other absorbent earths, of which there plainly appeared to
me to be very different kinds, although commonly confounded together
under one name. I was indeed led to this examination of the absorbent
earths, partly by the hope of discovering a new sort of lime and lime-
water, which might possibly be a more powerful solvent of the stone,
than that commonly used ; but was disappointed in my expectations.
I have had no opportunity of seeing Hoffman's first magnesia, or
the liquor from which it is prepared, and have therefore been obliged
to make my experiments upon the second.
In order to prepare it, I at first employed the bitter saline liquor
called bittern, which remains in the pans after the evaporation of sea-
water. But as that liquor is not always easily procured, I afterwards
made use of a salt called Epsom salt, which is separated from the bittern
by crystallization, and is evidently composed of magnesia and the vit-
riolic acid.
There is likewise a spurious kind of Glauber salt, which yields plenty
of magnesia, and seems to be no other than Epsom salt, of sea-water
reduced to crystals of a larger size. And common salt also affords a
small quantity of this powder ; because, being separated from the bittern
by one hasty crystallization only, it necessarily contains a portion of that
liquor.
Those who would prepare a magnesia from Epsom salt, may use
the following process :
Dissolve equal quantities of Epsom salt, and of pearl ashes, sep-
arately, in a sufficient quantity of water ; purify each solution from its
dregs, and mix them accurately together by violent agitation. Then
make them just to boil over a brisk fire.
Add now to the mixture, three or four times its quantity of hot
water ; after a little agitation, allow the magnesia to settle to the bottom,
and decant off as much of the water as possible. Pour on the same quan-
tity of cold water ; and, after settling, decant it off in the same manner.
Repeat this washing with the cold water ten or twelve times, or even
EIGHTEENTH CENTURY SCIENCE 275
oftener^ ff the magnesia be required perfectly pure for chemical experi-
ments.
Wljen it is sufficiently washed, the water may be strained and
squeezed from it in a linen cloth ; for very little of the magnesia passes
through.
The alkali in the mixture, uniting with the acid, separates it from
the magnesia; which, not being of itself soluble in water, must conse-
quently appear immediately under a solid form. But the powder which
thus appears is not entirely magnesia; part of it, is the neutral salt
formed from the union of the acid and alkali. This neutral salt is found,
upon examination, to agree in all respects with vitriolated tartar, and
requires a large quantity of hot water to dissolve it. As much of it is
therefore dissolved as the water can take up; the rest is dispersed
through the mixture, in the form of a powder. Hence the necessity of
washing the magnesia with so much trouble ; for the first effusion of hot
water is intended to dissolve the whole of the salt, and the subsequent
additions of cold water to wash away this solution.
The caution given, of boiling the mixture, is not unnecessary : if it
be neglected, the whole of the magnesia is not accurately separated at
once ; and, by allowing it to rest for some time, that powder concretes
into minute grains, which, when viewed with the microscope, appear to
be assemblages of needles diverging from a point. This happens more
especially when the solution of the Epsom salt, and of the alkali, are
diluted with too much water before they are mixed together. Thus, if
a dram of Epsom salt, and of salt of tartar, be dissolved each in four
ounces of water, and be mixed, and then allowed to rest three or four
days, the whole of the magnesia will be formed into these grains. Or,
if we filtrate the mixture soon after it is made, and heat the clear liquor
which passes through, it will become turbid, and deposit a magnesia.
An ounce of magnesia was exposed in a crucible, for about an hour,
to such a heat as is sufficient to melt copper. When taken out, it weighed
three drams and one scruple, or had lost 7-12 of its former weight.
I repeated, with the magnesia prepared in this manner, most of
those experiments I had already made upon it before calcination, and
the result was as follows : —
It dissolves in all the acids, and with these composes salts exactly
similar to those described in the first set of experiments : But, what is
particularly to be remarked, it is dissolved without any the least degree
of effervescence.
276 EIGHTEENTH CENTURY SCIENCE
It slowly precipitates the corrosive sublimate of mercury, in the
form of a black powder.
It separates the volatile alkali in salt-ammoniac from the acid, when
it is mixed with a warm solution of that salt. But it does not separate
an acid from a calcareous earth, nor does it introduce the least change
upon lime-water.
Lastly, when a dram of it is digested with an ounce of water in a
bottle for some hours, it does not make any the least change in the water.
The magnesia, when dried, is found to have gained ten grains; but it
neither effervesces with acids, nor does it sensibly affect lime-water.
Observing magnesia to lose such a remarkable proportion of its
weight in the fire, my next attempts were directed to the investigation of
this volatile part ; and, among other experiments, the following seemed
to throw some light upon it : —
Three ounces of magnesia were distilled in a glass retort and re-
ceiver, the fire being gradually increased until the magnesia was
obscurely red hot. When all was cool, I found only five drams of a
whitish water in the receiver, which had a faint smell of the spirit of
hartshorn, gave a green colour to the juice of violets, and rendered the
solutions of corrosive sublimate, and of silver, very slightly turbid. But
it did not sensibly effervesce with acids.
The magnesia, when taken out of the retort, weighed an ounce,
three drams, and thirty grains, or had lost more than half of its weight.
It still effervesced pretty briskly with acids, though not so strongly as
before this operation.
The fire should have been raised here to the degree requisite for the
perfect calcination of magnesia. But, even from this imperfect experi-
ment, it is evident, that, of the volatile parts contained in that powder, a
small proportion only is water; the rest cannot, it seems, be retained in
vessels, under a visible form. Chemists have often observed, in their
distillations, that part of a body has vanished from their senses, not-
withstanding the utmost care to retain it ; and they have always found,
upon further inquiry, that subtle part to be air, which having been
imprisoned in the body, under a solid form, was set free, and rendered
fluid and elastic by the fire. We may therefore safely conclude, that the
volatile matter lost in the calcination of magnesia, is mostly air; and
hence the calcined magnesia does not emit air, or make an effervescence
when mixed with acids.
The water, from its properties, seems to contain a small portion of
EIGHTEENTH CENTURY SCIENCE 277
volatile alkali, which was probably formed from the earth, air and water,
or from some of these combined together ; and perhaps also from a small
quantity of inflammable matter, which adhered accidentally to the mag-
nesia. Whenever chemists meet with this salt, they are inclined to
ascribe its origin to some animal or putrid vegetable substance ; and this
they have always done, when they obtained it from the calcareous earths,
all of which afford a small quantity of it. There is, however, no doubt,
that it can sometimes be produced independently of any such mixture,
since many fresh vegetables, and tartar, afford a considerable quantity
of it. And how can it, in the present instance, be supposed, that any ani-
mal or vegetable matter adhered to the magnesia, while it was dissolved
by an acid, separated from this by an alkali, and washed with so much
water ?
Two drams of magnesia were calcined in a cucible, in the manner
described above, and thus reduced to two scruples and twelve grains.
This calcined magnesia was dissolved in a sufficient quantity of spirit of
vitriol, and then again separated from the acid by the addition of an
alkali, of which a large quantity is necessary for this purpose. The
magnesia being very well washed and dried, weighed one dram and fifty
grains. It effervesced violently, or emitted a large quantity of air, when
thrown into acids ; formed a red powder, when mixed with a solution of
sublimate ; separated the calcareous earths from an acid, and sweetened
lime-water ; and had thus recovered all those properties which it had but
just now lost by calcination. Nor had it only recovered its original
properties, but acquired besides an addition of weight, nearly equal to
what had been lost in the fire ; and as it is found to effervesce with acids,
part of the addition must certainly be air.
This air seems to have been furnished by the alkali, from which it
was separated by the acid ; for Dr. Hales has clearly proved, that alka-
line salts contain a large quantity of fixed air, which they emit in great
abundance when joined to a pure acid. In the present case, the alkali is
really joined to an acid, but without any visible emission of air ; and yet
the air is not retained in it; for the neutral salt, into which it is con-
verted, is the same in quantity, and in every other respect, as if the acid
employed had not been previously saturated with magnesia, but offered
to the alkali in its pure state, and had driven the air out of it in their
conflict. It seems therefore evident, that the air was forced from the
alkali by the acid, and lodged itself in the magnesia.
These considerations led me to try a few experiments, whereby I
278 EIGHTEENTH CENTURY SCIENCE
might know what quantity of air is expelled from an alkali, or from
magnesia, by acids.
Two drams of a pure fixed alkaline salt, and an ounce of water,
were put into a Florentine flask, which, together with its contents,
weighed two ounces and two drams. Some oil of vitriol diluted with
water was dropped in, until the salt was exactly saturated ; which it was
found to be, when two drams, two scruples and three grains of this acid
had been added. The phial with its contents now weighed two ounces,
four drams and fifteen grains. One scruple, therefore, and eight grains,
were lost during the ebullition ; of which a trifling portion may be water,
or something of the same kind ; the rest is air.
PRIESTLEY
JOSEPH PRIESTLEY was born March 13, 1733, in Yorkshire, Eng-
land. Until twenty years old he studied under neighboring ministers,
and learned the classics and Hebrew, besides picking up French, Italian,
and German without assistance. Later he was sent to Daventry to a
non-conformist academy, and studied Chaldee, Syriac, and Arabic,
together with mathematics, physics, philosophy, and the like. At
twenty-two he took charge of a small church at Needham. In 1761 he
was appointed classical tutor at Warrington academy, and about this
time became interested in natural science. He joined the Royal Society
in 1/66, and the next year took the Mill Hill chapel at Leeds. In 1774
he discovered oxygen, called by him "dephlogisticated air." This is the
most definite of his results and the great importance of this gas made its
discovery have a tremendous influence. In addition, however, he was
either the first or among the first to prepare nitric oxide, hydrochloric
acid, etc.
As a theologian, Priestley was very liberal and came to believe in
the rule of law everywhere throughout the universe. In politics he was
a partisan of republicanism. On account of these views, his house was
burned in 1791 by a mob and all his papers and other valuable posses-
sions destroyed. From 1794 to his death in 1804 he found a pleasant
refuge in Northumberland, Pennsylvania.
EIGHTEENTH CENTURY SCIENCE 279
THE DISCOVERY OF OXYGEN
Presently, after my return from abroad, I went to work upon the
mercurius calcinatus, which I had procured from Mr. Cadet ; and, with
a very moderate degree of heat, I got from about one-fourth of an ounce
of it, an ounce-measure of air, which I observed to be not readily
imbibed, either by the substance itself from which it had been expelled
(for I suffered them to continue a long time together before I trans-
ferred the air to any other place) or by water, in which I suffered this air
to stand a considerable time before I made any experiment upon it.
In this air, as I had expected, a candle burned with a vivid flame ;
but what I observed new at this time (November 19), and which sur-
prised me no less than the fact I had discovered before, was, that,
whereas a few moments agitation in water will deprive the modified
nitrous air of its property of admitting a candle to burn in it ; yet, after
more than ten times as much agitation as would be sufficient to produce
this alteration in the nitrous air, no sensible change was produced in
this. A candle still burned in it with a strong flame ; and it did not, in
the least, diminish common air, which I have observed that nitrous air,
in this state, in some measure does.
But I was much more surprised, when, after two days, in which
this air had continued in contact with water (by which it was dimin-
ished about one-twentieth of its bulk) I agitated it violently in water
about five minutes, and found that a candle still burned in it as well as in
common air. The same degree of agitation would have made phlogisti-
cated nitrous air fit for respiration indeed, but it would certainly have
extinguished a candle.
These facts fully convinced me, that there must be a very material
difference between the constitution of the air from mercurius calcinatus,
and that of phlogisticated nitrous air, notwithstanding their resemblance
in some particulars. But though I did not doubt that the air from mer-
curius calcinatus was fit for respiration, after being agitated in water, as
every kind of air without exception, on which I had tried the experi-
ment, had been, I still did not suspect that it was respirable in the first
instance ; so far was I from having any idea of this air being, what it
really was, much superior, in this respect, to the air of the atmosphere.
In this ignorance of the real nature of this kind of air, I continued
280 EIGHTEENTH CENTURY SCIENCE
from this time (November) to the 1st of March following; having, in
the meantime, been intent upon my experiments on the vitriolic acid air
above recited, and the various modifications of air produced by spirit of
nitre, an account of which will follow. But in the course of this month,
I not only ascertained the nature of this kind of air, though very gradu-
ally, but was led to it by the complete discovery of the constitution of the
air we breathe.
Till this ist of March, 1775, I had so little suspicion of the air from
mercurius calcinatus, &c., being wholesome, that I had not even thought
of applying it to the test of nitrous air; but thinking (as my reader must
imagine I frequently must have done) on the candle burning in it after
long agitation in water, it occurred to me at last to make the experiment ;
and putting one measure of nitrous air to two measures of this air, I
found, not only that it was diminished, but that it was diminished quite
as much as common air, and that the redness of the mixture was like-
wise equal to that of a similar mixture of nitrous and common air.
After this I had no doubt but that the air from mercurius calcinatus
was fit for respiration, and that it had all the other properties of genuine
common air. But I did not take notice of what I might have observed,
if I had not been so fully possessed by the notion of there being no air
better than common air, that the redness was really deeper, and the
diminution something greater than common air would have admitted.
Moreover, this advance in the way of truth, in reality, threw me
back into error, making me give up the hypothesis I had first formed,
viz. that the mercurius calcinatus had extracted spirit of nitre from the
air; for I now concluded, that all the constituent parts of the air were
equally, and in their proper proportion, imbibed in the preparation of
this substance, and also in the process of making red lead. For at the
same time that I made the above mentioned experiment on the air from
mercurius calcinatus, I likewise observed that the air which I had ex-
tracted from red lead, after the fixed air was washed out of it, was of the
same nature, being diminished by nitrous air like common air : but, at the
same time, I was puzzled to find that air from the red precipitate was
diminished in the same manner, though the process for making this sub-
stance is quite different from that of making the two others. But to this
circumstance I happened not to give much attention.
I wish my reader be not quite tired with the frequent repetition of
the word surprise, and others of similar import ; but I must go on in that
style a little longer. For the next day I was more surprised than ever
EIGHTEENTH CENTURY SCIENCE 281
I had been before, with finding that, after the above-mentioned mixture
of nitrous air and the air from mercurius calcinatus, had stood all night,
(in which time the whole diminution must have taken place ; and, conse-
quently, had it been common air, it must have been made perfectly nox-
ious, and entirely unfit for respiration or inflammation) a candle burned
in it, and even better than in common air.
I cannot, at this distance of time, recollect what it was that I had in
view in making this experiment ; but I know I had no expectation of the
real issue of it. Having acquired a considerable degree of readiness in
making experiments of this kind, a very slight and evanescent motive
would be sufficient to induce me to do it. If, however, I had not hap-
pened, for some other purpose, to have had a lighted candle before me,
I should probably never have made the trial ; and the whole train of my
future experiments relating to this kind of air might have been pre-
vented.
Still, however, having no conception of the real cause of this phe-
nomenon, I considered it as something very extraordinary; but as a
property that was peculiar to air that was extracted from these
substances, and adventitious ; and I always spoke of the air to my
acquaintance as being substantially the same thing with common air. I
particularly remember my telling Dr. Price, that I was myself perfectly
satisfied of its being common air, as it appeared to be so by the test of
nitrous air ; though, for the satisfaction of others, I wanted a mouse to
make the proof quite complete.
On the 8th of this month I procured a mouse, and put it into a glass
vessel, containing two ounce-measures of the air from mercurius calcin-
atus. Had it been common air, a full-grown mouse, as this was, would
have lived in it about a quarter of an hour. In this air, however, my
mouse lived a full half hour; and though it was taken out seemingly
dead, it appeared to have been only exceedingly chilled ; for, upon being
held to fire, it presently revived, and appeared not to have received
any harm from the experiment.
By this I was confirmed in my conclusion, that the air extracted
from mercurius calcinatus, &c., was, at least, as good as common air;
but I did not certainly conclude that it was any better ; because, though
one mouse would live only a quarter of an hour in a given quantity of
air, I knew it was not impossible but that another mouse might have
lived in it half an hour ; so little accuracy is there in this method of ascer-
taining the goodness of air ; and indeed I have never had recourse to it
V 6-18
282 EIGHTEENTH CENTURY SCIENCE
for my own satisfaction, since the discovery of that most ready, accu-
rate, and elegant test that nitrous air furnishes. But in this case I had a
view to publishing the most generally satisfactory account of my experi-
ments that the nature of the thing would admit of.
This experiment with the mouse, when I had reflected upon it some
time, gave me so much suspicion that the air into which I had put it was
better than common air, that I was induced, the day after, to apply the
test of nitrous air to a small part of that very quantity of air which the
mouse had breathed so long ; so that, had it been common air, I was sat-
isfied it must have been very nearly, if not altogether, as noxious as pos-
sible, so as not to be affected by nitrous air ; when, to my surprise again,
I found that though it had been breathed so long, it was still better than
common air. For after mixing it with nitrous air, in the usual propor-
tion of two to one, it was diminished in the proportion of four and one-
half to three and one-half ; that is, the nitrous air had made it two-ninths
less than before, and this in a very short space of time ; whereas I had
never found that, in the longest time, any common air was reduced more
than one-fifth of its bulk by any proportion of nitrous air, nor more than
one-fourth by any phlogistic process whatever. Thinking of this
extraordinary fact upon my pillow, the next morning I put another
measure of nitrous air to the same mixture, and, to my utter astonish-
ment, found that it was farther diminished to almost one-half of its
original quantity. I then put a third measure to it; but this did not
diminish it any farther; but, however, left it one measure less than it
was even after the mouse had been taken out of it.
Being now fully satisfied that this air, even after the mouse had
breathed it half an hour, was much better than common air ; and having
a quantity of it still left, sufficient for the experiment, viz. an ounce-
measure and a half, I put the mouse into it; when I observed that it
seemed to feel no shock upon being put into it, evident signs of which
would have been visible, if the air had not been very wholesome; but
that it remained perfectly at its ease another full half hour, when I took
it out quite lively and vigorous. Measuring the air the next day, I found
it to be reduced from one and one-half to two-thirds of an ounce-meas-
ure. And after this, if I remember well (for in my register of the day I
only find it noted, that it was considerably diminished by nitrous air) ,
it was nearly as good as common air. It was evident, indeed, from the
mouse having been taken out quite vigorous, that the air could not have
been rendered very noxious.
EIGHTEENTH CENTURY SCIENCE 283
For my farther satisfaction I procured another mouse, and putting
it into less than two ounce-measures of air extracted from mercurius cal-
cinatus and air from red precipitate (which, having found them to be of
the same quality, I had mixed together) it lived three-quarters of an
hour. But not having had the precaution to set the vessel in a warm
place, I suspect that the mouse died of cold. However, as it had lived
three times as long as it could probably have lived in the same quantity
of common air, and I did not expect much accuracy from this kind of a
test, I did not think it necessary to make any more experiments with
mice.
Being now fully satisfied of the superior goodness of this kind of
air, I proceeded to measure that degree of purity, with as much accuracy
as I could, by the test of nitrous air ; and I began with putting one meas-
ure of nitrous air to two measures of this air, as if I had been examining
common air; and now I observed that the diminution was evidently
greater than common air would have suffered by the same treatment. A
second measure of nitrous air reduced it to two-thirds of its original
quantity, and a third measure to one-half. Suspecting that the diminu-
tion could not proceed much farther, I then added only half a measure
of nitrous air, by which it was diminished still more ; but not much, and
another half measure made it more than half of its original quantity ; so
that, in this case, two measures of this air took more than two measures
of nitrous air, and yet remained less than half of what it was. Five
measures brought it pretty exactly to its original dimensions.
At the same time, air from the red precipitate was diminished in the
same proportion as that from mercurius calcinatus, five measures of
nitrous air being received by two measures of this without any increase
of dimensions. Now as common air takes about one-half of its bulk of
nitrous air, before it begins to receive any addition to its dimensions
from more nitrous air, and this air took more than four half-measures
before it ceased to be diminished by more nitrous air, and even five half-
measures made no addition to its original dimensions, I conclude that it
was between four and five times as good as common air. It will be seen
that I have since procured air better than this, even between five and six
times as good as the best common air that I have ever met with.
284 EIGHTEENTH CENTURY SCIENCE
SCHEELE
KARL WILHELM SCHEELE was born at Stralsund, Pomerania, then a
part of Sweden, on December 19, 1742. His father was a merchant. In
school young Karl early showed a taste for pharmacy and was appren-
ticed to an apothecary in Gothenburg.
The rest of his life, though lived in various places, was occupied
with his chemical experiments. In fact, he was one of the most inde-
fatigable experimenters in the history of the science. In 1777 he
published his treatise on "Air and Fire," in which he discovered inde-
pendently of the English chemists the double composition of air. He
died in 1786.
CHEMICAL TREATISE ON AIR AND FIRE
1. It is the object and chief business of chemistry to skilfully sep-
arate substances into their constituents, to discover their properties, and
to compound them in different ways.
How difficult it is, however, to carry out such operations with the
greatest accuracy, can only be unknown to one who either has never
undertaken this occupation, or at least has not done so with sufficient
attention.
2. Hitherto chemical investigators are not agreed as to how many
elements or fundamental materials compose all substances. In fact this
is one of the most difficult problems ; some indeed hold that there re-
mains no further hope of searching out the elements of substances. Poor
comfort for those who feel their greatest pleasure in the investigation of
natural things ! Far is he mistaken, who endeavours to confine chem-
istry, this noble science, within such narrow bounds! Others believe
that earth and phlogiston are the things from which all material nature
has derived its origin. The majority seem completely attached to the
peripatetic elements.
3. I must admit that I have bestowed no little trouble upon this
EIGHTEENTH CENTURY SCIENCE 285
matter in order to obtain a clear conception of it. One may reasonably
be amazed at the numerous ideas and conjectures which authors have
recorded on the subject, especially when they give a decision respecting
the phenomenon of fire ; and this very matter was of the greatest import-
ance to me. I perceived the necessity of a knowledge of fire, because
without this it is not possible to make any experiment ; and without fire
and heat it is not possible to make use of the action of any solvent. I
began accordingly to put aside all explanations of fire; I undertook a
multitude of experiments in order to fathom this beautiful phenomenon
as fully as possible. I soon found, however, that one could not form any
true judgment regarding the phenomena which fire presents, without a
knowledge of the air. I saw, after carrying out a series of experiments,
that air really enters into the mixture of fire, and with it forms a constit-
uent of flame and of sparks. I learned accordingly that a treatise like
this, on fire, could not be drawn up with proper completeness without
taking the air also into consideration.
4. Air is that fluid invisible substance which we continually breathe,
which surrounds the whole surface of the earth, is very elastic, and pos-
sesses weight. It is always filled with an astonishing quantity of all
kinds of exhalations, which are so finely subdivided in it that they are
scarcely visible even in the sun's rays. Water vapours always have the
preponderance amongst these foreign particles. The air, however, is also
mixed with another elastic substance resembling air, which differs from
it in numerous properties, and is, with good reason, called aerial acid
by Professor Bergman. It owes its presence to organised bodies, de-
stroyed by putrefaction or combustion.
5. Nothing has given philosophers more trouble for some years
than just this delicate acid or so-called fixed air. Indeed it is not sur-
prising that the conclusions which one draws from the properties of this
elastic acid are not favourable to all who are prejudiced by previously
conceived opinions. These defenders of the Paracelsian doctrine believe
that the air is in itself unalterable ; and, with Hales, that it really unites
with substances thereby losing its elasticity ; but that it regains its orig-
inal nature as soon as it is driven out of these by fire or fermentation.
But since they see that the air so produced is endowed with properties
quite different from common air, they conclude, without experimental
proofs, that this air has united with foreign materials, and that it must
be purified from these admixed foreign particles by agitation and filtra-
tion with various liquids. I believe that there would be no hesitation in
286 EIGHTEENTH CENTURY SCIENCE
accepting this opinion, if one could only demonstrate clearly by experi-
ments that a given quantity of air is capable of being completely
converted into fixed or other kind of air by the admixture of foreign
materials; but since this has not been done, I hope I do not err if I
assume as many kinds of air as experiment reveals to me. For when I
have collected an elastic fluid, and observe concerning it that its expan-
sive power is increased by heat and diminished by cold, while it still uni-
formly retains its elastic fluidity, but also discover in it properties and
behavior different from those of common air, then I consider myself
justified in believing that this is a peculiar kind of air. I say that air
thus collected must retain its elasticity even in the greatest cold, because
otherwise an innumerable multitude of varieties of air would have to be
assumed, since it is very probable that all substances can be converted by
excessive heat into a vapour resembling air.
6. Substances which are subjected to putrefaction or to destruction
by means of fire diminish, and at the same time consume, a part of the
air ; sometimes it happens that they perceptibly increase the bulk of the
air, and sometimes finally that they neither increase nor diminish a given
quantity of air — phenomena which are certainly remarkable. Con-
jectures can here determine nothing with certainty, at least they can only
bring small satisfaction to a chemical philosopher, who must have his
proofs in his hands. Who does not see the necessity of making experi-
ments in this case, in order to obtain light concerning this secret of
nature ?
7. General properties of ordinary air.
(i.) Fire must burn for a certain time in a given quantity of air.
(2.) If, so far as can be seen, this fire does not produce during combus-
tion any fluid resembling air, then, after the fire has gone out of itself,
the quantity of air must be diminished between a third and a fourth
part. (3.) It must not unite with common water. (4.) All kinds of
animals must live for a certain time in a confined quantify of air. (5.)
Seeds, as for example peas, in a given quantity of similarly confined air,
must strike roots and attain a certain height with the aid of some water
and of a moderate heat.
Consequently, when I have a fluid resembling air in its external
appearance, and find that it has not the properties mentioned, even when
only one of them is wanting, I feel convinced that it is not ordinary air.
8. Air must be composed of elastic fluids of two kinds.
First Experiment. — I dissolved one ounce of alkaline liver of sul-
EIGHTEENTH CENTURY SCIENCE 287
phur in eight ounces of water ; I poured four ounces of this solution into
an empty bottle capable of holding 24 ounces of water, and closed it most
securely with a cork ; I then inverted the bottle and placed the neck in a
small vessel with water ; in this position I allowed it to stand for four-
teen days. During this time the solution had lost a part of its red colour
and had also deposited some sulphur: afterwards I took the bottle
and held it in the same position in a larger vessel with water, so that the
mouth was under and the bottom above the water-level, and withdrew
the cork under the water ; immediately water rose with violence into the
bottle. I closed the bottle again, removed it from the water, and
weighed the fluid which it contained. There were 10 ounces. After
subtracting from this the four ounces of solution of sulphur there re-
main six ounces, consequently it is apparent from this experiment that
of 20 parts of air six parts have been lost in 14 days.
9. Second Experiment. — (a) I repeated the preceding experiment
with the same quantity of liver of sulphur, but with this difference that I
only allowed the bottle to stand a week tightly closed. I then found that
of 20 parts of air only 4 had been lost, (b) On another occasion I
allowed the very same bottle to stand four months; the solution still
possessed a somewhat dark yellow colour. But no more air had been
lost than in the first experiment, that is to say six parts.
10. Third Experiment. — I mixed two ounces of caustic ley, which
was prepared from alkali of tartar and unslaked lime and did not pre-
cipitate lime-water, with half an ounce of the preceding solution of sul-
phur, which likewise did not precipitate lime-water. This mixture had
a yellow colour. I poured it into the same bottle, and after this had
stood fourteen days, well closed, I found the mixture entirely without
colour and also without precipitate. I was enabled to conclude that
the air in this bottle had likewise diminished, from the fact that air
rushed into the bottle with a hissing sound after I had made a small hole
in the cork.
11. Fourth Experiment. — (a.) I took four ounces of a solution of
sulphur in lime water ; I poured this solution into a bottle and closed it
tightly. After 14 days the yellow colour had disappeared, and of 20
parts of air 4 parts had been lost. The solution contained no sul-
phur, but had allowed a precipitate to fall which was chiefly gypsum.
(b.) Volatile liver of sulphur likewise diminishes the bulk of air. (c)
Sulphur, however, and volatile spirit of sulphur, undergo no alteration
in it.
288 EIGHTEENTH CENTURY SCIENCE
12. Fifth Experiment. — I hung up over burning sulphur, linen rags
which were dipped in a solution of alkali of tartar. After the alkali was
saturated with the volatile acid, I placed the rags in a flask, and closed
the mouth most carefully with a wet bladder. After three weeks had
elapsed I found the bladder strongly pressed down ; I inverted the flask,
held its mouth in water and made a hole in the bladder; thereupon
water rose with violence into the flask and filled the fourth part.
13. Sixth Experiment. — I collected in the bladder the nitrous acid
which arises on the dissolution of the metals in nitrous acid, and after I
had tied the bladder tightly I laid it in a flask and secured the mouth
very carefully with a wet bladder. The nitrous air gradually lost its
elasticity, the bladder collapsed, and became yellow as if corroded by
aqua fortis. After 14 days I made a hole in the bladder tied over the
flask, having previously held it, inverted, under water; the water rose
rapidly into the flask, and it remained only two-thirds empty.
14. Seventh Experiment. — (a.) I immersed the mouth of a flask in
a vessel with oil of turpentine. The oil rose in the flask a few lines
every day. After the lapse of 14 days the fourth part of the flask was
filled with it. I allowed it to stand for three weeks longer, but the oil did
not rise higher. All those oils which dry in the air, and become con-
verted into resinous substances, possess this property. Oil of turpen-
tine, however, and linseed oil rise up sooner if the flask is previously
rinsed out with a concentrated sharp ley. (b.) I poured two ounces of
colourless and transparent animal oil of Dippel into a bottle and closed
it very tightly ; after the expiration of two months the oil was thick and
black. I then held the bottle, inverted, under water and drew out the
cork ; the bottle immediately became one- fourth filled with water.
15. Eighth Experiment. — (a.) I dissolved two ounces of vitriol of
iron in thirty-two ounces of water, and precipitated this solution with a
caustic ley. After the precipitate had settled, I poured away the clear
fluid and put the dark green precipitate of iron so obtained, together
with the remaining water, into the before-mentioned bottle (§8), and
closed it tightly. After 14 days (during which time I shook the bottle
frequently, this green calx of iron had acquired the colour of crocus of
iron, and of 40 parts of air 12 had been lost, (b.) When iron filings
are moistened with some water and preserved for a few weeks in a well
closed bottle, a portion of the air is likewise lost, (c.) The solution of
iron in vinegar has the same effect upon air. In this case the vinegar
permits the dissolved iron to fall out in the form of a yellow crocus, and
EIGHTEENTH CENTURY SCIENCE 289
becomes completely deprived of this metal, (d.) The solution of cop-
per prepared in closed vessels with spirit of salt likewise diminishes air.
In none of the foregoing kinds of air can either a candle burn or the
smallest spark glow.
1 6. It is seen from these experiments that phlogiston, the simple
inflammable principle, is present in each of them. It is known that the
air strongly attracts to itself the inflammable part of substances and
deprives them of it: not only this may be seen from the experiments
cited, but it is at the same time evident that on the transference of the
inflammable substance to the air a considerable part of the air is lost.
But that inflammable substance alone is the cause of this action, is
plain from this, that, according to the tenth paragraph, not the least
trace of sulphur remains over, since, according to my experiments this
colourless ley contains only some vitriolated tartar. The eleventh para-
graph likewise shews this. But since sulphur alone, and also the vola-
tile spirit of sulphur, have no effect upon the air (§ II. c), it is clear
that the decomposition of liver of sulphur takes place according to the
laws of double affinity — that is to say, that the alkalies and lime attract
the vitriolic acid, and the air attracts the phlogiston.
It may also be seen from the above experiments, that a given quan-
tity of air can only unite with, and at the same time saturate, a certain
quantity of the inflammable substance : this is evident from the ninth
paragraph, letter b. But whether the phlogiston which was lost by the
substances was still present in the air left behind in the bottle, or whether
the air which was lost had united and fixed itself with the materials such
as liver of sulphur, oils, &c., are questions of importance.
From the first view, it would necessarily follow that the inflam-
mable substance possessed the property of depriving the air of part of its
elasticity, and that in consequence of this it becomes more closely com-
pressed by the external air. In order now to help myself out of these
uncertainties, I formed the opinion that any such air must be specifically
heavier than ordinary air, both on account of its containing phlogiston
and also of its greater condensation. But how perplexed was I when I
saw that a very thin flask which was filled with this air, and most accu-
rately weighed, not only did not counterpoise an equal quantity of
ordinary air, but was even somewhat lighter. I then thought that the
latter view might be admissible ; but in that case it would necessarily fol-
low also that the lost air could be separated again from the materials
employed. None of the experiments cited seemed to me capable of
290 EIGHTEENTH CENTURY SCIENCE
shewing this more clearly than that according to the tenth paragraph,
because this residuum, as already mentioned, consists of vitriolated tar-
tar and alkali. In order therefore to see whether the lost air had been
converted into fixed air, I tried whether the latter shewed itself when
some of the caustic ley was poured into lime water ; but in vain — no pre-
cipitation took place. Indeed, I tried in several ways to obtain the lost
air from this alkaline mixture, but as the results were similar to the
foregoing, in order to avoid prolixity I shall not cite these experiments.
Thus much I see from the experiments mentioned, that the air consists
of two fluids, differing from each other, the one of which does not man-
ifest in the least the property of attracting phlogiston, while the other,
which composes between the third and the fourth part of the whole mass
of the air, is peculiarly disposed to such attraction. But where this lat-
ter kind of air has gone to after it has united with the inflammable sub-
stance, is a question which must be decided by further experiments, and
not by conjectures.
CAVENDISH
HENRY CAVENDISH was born at Nice, Italy, October 10, 1731. He
studied at Cambridge, but took no degree there. In 1760 he joined the
Royal Society, and his Thursday dinners there were almost his only
communication with the world. His large fortune let him devote him-
self to science.
In 1766 he discovered hydrogen, and some years later, after
Priestley had discovered oxygen, Cavendish found that the combination
of the two gases produce water. A little later he showed that when
nitrogen from the air is present, the result is nitric acid.
These experiments opened up a vast field for research, and have
proved of immense importance.
In 1783 he made the guess that heat was a motion rather than a
substance. In 1798 he measured the density of the earth by suspending
a horizontal bar by a wire, and comparing its horizontal vibrations (or
part-swings) with the time of the same vibrations when two large
masses of lead were placed at the ends of the case. His result made the
EIGHTEENTH CENTURY SCIENCE 291
earth's density about five and one-half times that of water. Cavendish
was also interested in electricity, and believed it to be an elastic fluid.
He died in 1810.
THE COMBINATION OF HYDROGEN AND OXYGEN INTO
WATER
In Dr. Priestley's last volume of experiments is related an experi-
ment of Mr. Warltire's, in which it is said that, on firing a mixture of
common and inflammable air by electricity in a close copper vessel hold-
ing about three pints, a loss of weight was always perceived, on an aver-
age about two grains, though the vessel was stopped in such a manner
that no air could escape by the explosion. It is also related, that on
repeating the experiment in glass vessels, the inside of the glass, though
clean and dry before, immediately became dewy; which confirmed an
opinion he had long entertained, that common air deposits its moisture
by phlogistication. As the latter experiment seemed likely to throw
great light on the subject I had in view, I thought it well worth exam-
ining more closely. The first experiment also, if there was no mistake
in it, would be very extraordinary and curious ; but it did not succeed
with me ; for though the vessel I used held more than Mr. Warltire's,
namely, 24,000 grains of water, and though the experiment was repeated
several times with different proportions of common and inflammable
air, I could never perceive a loss of weight of more than one-fifth of a
grain, and commonly none at all. It must be observed, however, that
though there were some of the experiments in which it seemed to dimin-
ish a little in weight, there were none in which it increased.
In all the experiments, the inside of the glass globe became dewy, as
observed by Mr. Warltire ; but not the least sooty matter could be per-
ceived. Care was taken in all of them to find how much the air was
diminished by the explosion, and to observe its test. The result is as
follows, the bulk of the inflammable air being expressed in decimals of
the common air :
292
EIGHTEENTH CENTURY SCIENCE
Common
Air.
Inflammable
Air.
Diminution.
Air Remaining
after the
Explosion.
Test of this
Air in the
First Method.
Standard.
i
1.241
.686
1-555
•055
o
J-955
.642
1-423
063
o
.706
.647
i.°59
.066
o
.423
.612
.811
.097
<>3
• 331
.476
.855
•339
.206
.294
.912
.648
58
In these experiments the inflammable air was procured from zinc,
as it was in all my experiments, except where otherwise expressed : but
I made two more experiments, to try whether there was any difference
between the air from zinc and that from iron, the quantity of inflam-
mable air being the same in both, namely, 0,331 of the common; but I
could not find any difference to be depended on between the two kinds
of air, either in the diminution which they suffered by the explosion, or
the test of the burnt air.
From the fourth experiment it appears, that 423 measures of
inflammable air are nearly sufficient to completely phlogisticate 1000 of
common air ; and that the bulk of the remaining air after the explosion
is then very little more than four-fifths of the common air employed ; so
that as common air cannot be reduced to a much less bulk than that by
any method of phlogistication, we may safely conclude, that when they
are mixed in this proportion, and exploded, almost all the inflammable
air, and about one-fifth part of the common air, lose their elasticity, and
are condensed into the dew which lines the glass.
The better to examine the nature of this dew, 500,000 grain meas-
ures of inflammable air were burnt with about two and one-half times
that quantity of common air, and the burnt air made to pass through a
glass cylinder eight feet long and three-quarters of an inch in diam-
eter, in order to deposit the dew. The two airs were conveyed slowly
into this cylinder by separate copper pipes, passing through a brass
plate which stopped up the end of the cylinder ; and as neither inflam-
mable nor common air can burn by themselves, there was no danger of
the flame spreading into the magazines from which they were conveyed.
Each of these magazines consisted of a large tin vessel, inverted into
another vessel just big enough to receive it. The inner vessel communi-
cated with the copper pipe, and the air was forced out of it by pouring
water into the outer vessel ; and in order that the quantity of common
air expelled should be two and one-half times that of the inflammable,
EIGHTEENTH CENTURY SCIENCE 293
the water was let into the outer vessels by two holes in the bottom of the
same tin pan, the hole which conveyed the water into that vessel in which
the common air was confined being two and one-half times as big as the
other.
In trying the experiment, the magazines being first filled with their
respective airs, the glass cylinder was taken off, and water let, by the
two holes, into the outer vessels, till the airs began to issue from the ends
of the copper pipes ; they were then set on fire by a candle, and the cylin-
der put on again in its place. By this means upwards of 135 grains of
water were condensed in the cylinder, which had no taste nor smell, and
which left no sensible sediment when evaporated to dryness ; neither did
it yield any pungent smell during evaporation ; in short, it seemed pure
water.
In my first experiment, the cylinder near that part where the air
was fired was a little tinged with sooty matter, but very slightly so ; and
that little seemed to proceed from the putty with which the apparatus
was luted, and which was heated by the flame; for in another experi-
ment, in which it was contrived so that the luting should not be much
heated, scarce any sooty tinge could be perceived.
By the experiments with the globe it appeared, that when inflam-
mable and common air are exploded in a proper proportion, almost all
the inflammable air, and nearly one-fifth of the common air, lose their
elasticity, and are condensed into dew. And by this experiment it
appears, that this dew is plain water, and consequently that almost all
the inflammable air and about one-fifth of the common air, are turned
into pure water.
In order to examine the nature of the matter condensed on firing a
mixture of dephlogisticated and inflammable air, I took a glass globe
holding 8,800 grain measures, furnished with a brass cock and an appar-
atus for firing air by electricity. This globe was well exhausted by an
air-pump, and then filled with a mixture of inflammable and dephlo-
gisticated air, by shutting the cock, fastening a bent glass tube to its
mouth, and letting up the end of it into a glass jar inverted into water,
and containing a mixture of 19,500 grain measures of dephlogisticated
air, and 37,000 of inflammable ; so that, upon opening the cock, some of
this mixed air rushed through the bent tube, and filled the globe. The
cock was then shut, and the included air fired by electricity, by which
means almost all of it lost its elasticity. The cock was then again opened,
so as to let in more of the same air, to supply the place of that destroyed
294 EIGHTEENTH CENTURY SCIENCE
by the explosion, which was again fired, and the operation continued
till almost the whole of the mixture was let into the globe and exploded.
By this means, though the globe held not more than the the sixth part
of the mixture, almost the whole of it was exploded therein, without
any fresh exhaustion of the globe.
As I was desirous to try the quantity and test of this burnt air,
without letting any water into the globe, which would have prevented
my examining the nature of the condensed matter, I took a larger globe,
furnished also with a stop cock, exhausted it by an air-pump, and
screwed it on upon the cock of the former globe ; upon which, by open-
ing both cocks, the air rushed out of the smaller globe into the larger,
till it became of equal density in both ; then, by shutting the cock of the
larger globe, unscrewing it again from the former, and opening it under
water, I was enabled to find the quantity of the burnt air in it ; and con-
sequently, as the proportion which the contents of the two globes bore
to each other was known, could tell the quantity of burnt air in the small
globe before the communication was made between them. By this
means the whole quantity of the burnt air was found to be 2,950 grain
measures ; its standard was 1,85.
The liquor condensed in the globe, in weight about thirty grains,
was sensibly acid to the taste, and by saturation with fixed alkali, and
evaporation, yielded near two grains of nitre; so that it consisted of
water united to a small quantity of nitrous acid. No sooty matter was
deposited in the globe. The dephlogisticated air used in this experi-
ment was procured from red precipitate, that is, from a solution of
quicksilver in spirit of nitre distilled till it acquires a red colour.
As it was suspected, that the acid contained in the condensed liquor
was no essential part of the dephlogisticated air, but was owing to some
acid vapour which came over in making it and had not been absorbed by
the water, the experiment was repeated in the same manner, with some
more of the same air, which had been previously washed with water, by
keeping it a day or two in a bottle with some water, and shaking it fre-
quently; whereas that used in the preceding experiment had never
passed through water, except in preparing it. The condensed liquor was
still acid.
The experiment was also repeated with dephlogisticated air, pro-
cured from red lead by means of oil of vitriol ; the liquor condensed was
acid, but by an accident I was prevented from determining the nature
of the acid.
EIGHTEENTH CENTURY SCIENCE 295
I also procured some dephlogisticated air from the leaves of plants,
in the manner of Doctors Ingenhousz and Priestley, and exploded it
with inflammable air as before ; the condensed liquor still continued acid,
and of the nitrous kind.
In all these experiments the proportion of inflammable air was such,
that the burnt air was not much phlogisticated ; and it was observed,
that the less phlogisticated it was, the more acid was the condensed
liquor. I therefore made another experiment, with some more of the
same air from plants, in which the proportion of inflammable air was
greater, so that the burnt air was almost completely phlogisticated, its
standard being i-io. The condensed liquor was then not at all acid,
but seemed pure water ; so that it appears, that with this kind of dephlo-
gisticated air, the condensed liquor is not at all acid, when the two airs
are mixed in such a proportion that the burnt air is almost completely
phlogisticated, but is considerably so when it is not much phlogisticated.
In order to see whether the same thing would obtain with air pro-
cured from red precipitate, I made two more experiments with that kind
of air, the air in both being taken from the same bottle, and the experi-
ment tried in the same manner, except that the proportions of inflam-
mable air were different. In the first, in which the burnt air was almost
completely phlogisticated, the condensed liquor was not at all acid. In
the second, in which its standard was 1.86, that is, not much phlogis-
ticated, it was considerably acid ; so that with this air, as well as with
that from plants, the condensed liquor contains, or is entirely free from,
acid, according as the burnt air is less or more phlogisticated; and
there can be little doubt but that the same rule obtains with any other
kind of dephlogisticated air.
In order to see whether the acid, formed by the explosion of dephlo-
gisticated air obtained by means of the vitriolic acid, would also be of
the nitrous kind, I procured some air from turbith mineral, and exploded
it with inflammable air, the proportion being such that the burnt air was
not much phlogisticated. The condensed liquor manifested an acidity,
which appeared, by saturation with a solution of salt of tartar, to
be of the nitrous kind ; and it was found, by the addition of some terra
ponderosa salita, to contain little or no vitriolic acid.
When inflammable air was exploded with common air, in such a
proportion that the standard of the burnt air was about 4-10, the con-
densed liquor was not in the least acid. There is no difference, how-
ever, in this respect between common air, and dephlogisticated air mixed
296 EIGHTEENTH CENTURY SCIENCE
with phlogisticated in such a proportion as to reduce it to the standard
of common air ; for some dephlogisticated air from red precipitate, being
reduced to this standard by the addition of perfectly phlogisticated air,
and then exploded with the same proportion of inflammable air as the
common air was in the foregoing experiment, the condensed liquor was
not in the least acid.
From the foregoing experiments it appears, that when a mixture of
inflammable and dephlogisticated air is exploded in such proportion that
the burnt air is not much phlogisticated, the condensed liquor contains a
little acid, which is always of the nitrous kind, whatever substance the
dephlogisticated air is procured from ; but if the proportion be such that
the burnt air is almost entirely phlogisticated, the condensed liquor is not
at all acid, but seems pure water, without any addition whatever ; and as,
when they are mixed in that proportion, very little air remains after the
explosion, almost the whole being condensed, it follows that almost the
whole of the inflammable and dephlogisticated air is converted into pure
water. It is not easy, indeed, to determine from these experiments what
proportion the burnt air, remaining after the explosions, bore to the
dephlogisticated air employed, as neither the small nor the large globe
could be perfectly exhausted of air, and there was no saying with exact-
ness what quantity was left in them ; but in most of them, after allowing
for this uncertainty, the true quantity of burnt air seemed not more than
1-17 of the dephlogisticated air employed, or 1-50 of the mixture. It
seems, however, unnecessary to determine this point exactly, as the
quantity is so small, that there can be little doubt but that it proceeds
only from the impurities mixed with the dephlogisticated and inflam-
mable air, and consequently that, if those airs could be obtained per-
fectly pure, the whole would be condensed.
With respect to common air, and dephlogisticated air reduced by
the addition of phlogisticated air to the standard of common air, the case
is different ; as the liquor condensed in exploding them with inflammable
air, I believe I may say in any proportion, is not at all acid; perhaps
because if they are mixed in such a proportion as that the burnt air is not
much phlogisticated, the explosion is too weak, and not accompanied
with sufficient heat.
All the foregoing experiments, on the explosion of inflammable air
with common and dephlogisticated airs, except those which relate to the
cause of the acid found in the water, were made in the summer of the
year 1781, and were mentioned by me to Dr. Priestley, who in conse-
R1GHTBKNT ~ it
qtteAce of it made some experiments of th<» S&JTK kind, fts he relates in a
paper printed in the preceding vokurur .j( 1 rtsrt.Kacbon* During the
iMl summer also, a friend 01 . accour.t of thetn to M.
Lavoisier, as well as of the <x.TKM*k,-r
gi«ticated air is only water depri .
so far was M. Lavoisier from thinking am
till he was prevailed upon to repeat the expert
some difficulty in believing that nearly the wlioi
converted into water. It is remarkable, that neither •.-*' rie.1--- sr»'
found anv acid in the water produced by the combustion' which nigfr
v;r«x*t:«"1 f-T»m the latter having burnt the t\yo airs in a different mannr-
rr->r- -v'..-'t ! ••}'!:' aiid from the former having u-ed a different him! of
;kit irot-! gl&rcoal, and peiliap> having tt>od ,i
5i3I8IOVAJ
Ail I'.:'' early life was uevotni to the ir.o-t ;r-diiuU3 ^fu-jv . in \ ,-
•..••as voted the geld prize for his rssay on the i>est \va> of lighting i'an^.
: ->e had lived iii a dark r-x/m for six weeks in making his experiment? on
v '»".•.* ?7'r'') ^'^ stTcntiCT? wi»a cail-.'fi to the Kngllsh expertmeuts or
•*>•?&'• f .* -t rs H«.- ar>A!*ked tlie pre%aii'.ng phluu'.-"" .»
ttc>* principle* •»* iA^ •=!
prominent fani-cr *^i ;t»c **«*•* (publican) in
id to many improvm<*ot> »r pi^>liv administration.
.- of the Revolution a charge was made against all
LAVOISIER
Engraving from an original picture by
\
EIGHTEENTH CENTURY SCIENCE 297
quence of it made some experiments of the same kind, as he relates in a
paper printed in the preceding volume of the Transactions. During the
last summer also, a friend of mine gave some account of them to M.
Lavoisier, as well as of the conclusion drawn from them, that dephlo-
gisticated air is only water deprived of phlogiston; but at that time
so far was M. Lavoisier from thinking any such opinion warranted, that,
till he was prevailed upon to repeat the experiment himself, he found
some difficulty in believing that nearly the whole of the two airs could be
converted into water. It is remarkable, that neither of these gentlemen
found any acid in the water produced by the combustion ; which might
proceed from the latter having burnt the two airs in a different manner
from what I did ; and from the former having used a different kind of
inflammable air, namely, that from charcoal, and perhaps having used a
greater proportion of it.
LAVOISIER
ANTOINE LAURENT LAVOISIER was born in Paris, August 26, 1743.
All his early life was devoted to the most arduous study. In 1766 he
was voted the gold prize for his essay on the best way of lighting Paris.
He had lived in a dark room for six weeks in making his experiments on
the subject.
About 1770 his attention was called to the English experiments on
gases — the so-called "new airs." He attacked the prevailing phlogiston
theory of combustion and gave to Priestley's "dephlogisticated air" the
virtue of being the universal acidifying gas, calling it oxygen. He
declared combustion to be the act of some part of the substance combin-
ing with oxygen. He systematized chemistry and renamed the elements
and their compounds. Chemical reaction came to him to have the cer-
tainty of an algebraic equation, and from this was developed the great
idea of the persistence of matter, no difference what are the changes.
This is one of the greatest principles of modern science.
Lavoisier was a prominent farmer of the taxes (publican) in
France, and lent his aid to many improvements in public administration.
During the mad times of the Revolution a charge was made against all
V 6-19
298 EIGHTEENTH CENTURY SCIENCE
farmers-general, and in spite of his greatness Lavoisier was sent to the
guillotine May 6, 1794.
THE PERMANENCE OF MATTER
It results from the experiments described in chapters V and VI of
the work which I published at the beginning of this year, under the title
Opuscules Physiques et Chimiques, that when lead or tin is calcined in
a retort (verre ardent} under a bell-glass plunged in water or in mer-
cury, the volume of air is diminished about one-twentieth as a result of
the calcination, while the weight of the metal is found to be increased
by an amount approximately equal to that of the air destroyed or
absorbed.
I felt justified in concluding from these experiments that a portion
of the air itself, or of some substance contained in the air, and which
exists there in an elastic state, combined with the metals during their
calcination, and that the augmentation in weight of the metallic calxes
was due to this cause.
The effervescence which constantly takes place in every revivifica-
tion of metallic calxes, that is to say whenever a metallic substance
passes from the condition of the calx (oxide) to that of the metal, came
to the support of this theory. I think I have proved that this efferves-
cence is due to the freeing of an elastic fluid, a kind of air (gas) which
can be retained and measured, and the result of the many experiments
to which I have subjected it is that when it had been separated from the
metals by the addition of powdered charcoal, or any substance contain-
ing phlogiston, it did not differ in any respect from the substance to
which I have given the name of fixed air, mephitic gas, mephitic acid,
all synonymous terms, and that this gas was precisely the same whether
disengaged from metallic calxes by means of powdered charcoal, from
vegetable substances by fermentation, or from alkalies, saline or earthy,
by their solution in acids. — Lavoisier on the Calcination of Tin,
Oeuvres II., 105.
We began (our experiment) by testing what should be the opening
of the stop-cocks to provide the due proportion of the two gases. This
was easily ascertained by observing the color and brilliancy of the little
tongues of flame which formed at the end of the tube, the right propor-
EIGHTEENTH CENTURY SCIENCE 299
tion of the two gases giving the most luminous and beautiful flame.
This first point determined, we inserted the tube into the stem of the
receiver, which was plunged into mercury, and allowed the gases to
burn till we had used up all we had provided. From the first instant we
saw the walls of the receiver becoming obscured and covered with
vapor; soon this collected into drops and ran down upon the mercury
from all sides, and in fifteen or twenty minutes its surface was com-
pletely covered. The difficulty was to collect this water, but that was
easily accomplished by passing a plate under the receiver without tak-
ing that out of the mercury, and then pouring both the water and mer-
cury into a glass funnel ; finally letting the mercury run off, the water
remained collected in the tube of the funnel ; it weighed a little less than
five drams (gross).
This water, subjected to every imaginable test, seemed as pure as
distilled water ; it did not redden at all the tincture of turnsol ; nor turn
green the syrup of violets ; it did not precipitate lime-water ; finally, one
could not by any known reagents discover in it the slightest trace of
admixture.
As the two airs [gases] were conducted from pneumatic receptacles
(caisses) to the receiver through flexible leather pipes, and these were
not absolutely impermeable to the air (gas) it was not possible for us
to be certain as to the exact quantity of the two gases whose combus-
tion we had thus brought about ; but as it is not less true in physics than
in geometry that the whole is equal to its parts, and as we had obtained
by this experiment only pure water, without any other residue, we
thought ourselves justified in concluding that the weight of this water
was equal to that of the two gases which had served to produce it. But
one reasonable objection could be brought against this conclusion : ad-
mitting that the water produced was equal in weight to the two gases,
was to suppose that the matter of the heat and light so abundantly set
free in this operation, and which passes through the pores of the ves-
sels, had no weight ; which assumption might be regarded as gratuitous.
I found myself, therefore, confronted with this important question:
whether the matter of heat and light has any sensible and appreciable
weight in physical experiments, and I decided in the negative on the
strength of facts which seemed to me conclusive and which I have set
forth in a memoir deposited some months ago with the secretary of the
Academy. — Lavoisier on the Composition of Water, Oeuvres II., 338,
339-
300 EIGHTEENTH CENTURY SCIENCE
THE NATURE OF COMBUSTION
Emboldened by these reflections, I venture to submit to the Acad-
emy today a new theory of combustion, or rather, to speak with that
reserve to whose law I submit myself, an hypothesis, by the aid of
which all the phenomena of combustion, calcination, and even to some
extent those accompanying the respiration of animals are explained in a
very satisfactory manner. I had already laid the foundations of this
hypothesis p. 279-280 of vol. I. of my Opuscules physiques et chimiques;
but I admit that trusting little to my own knowledge, I did not then dare
to put forward an opinion which might seem singular, and which was
directly opposed to the theory of Stahl and of many celebrated men who
have followed him.
Though perhaps some of the reasons which then checked me still
remain today, nevertheless, the facts which have multiplied since that
time, and which seem to me favorable to my views, have confirmed me in
my opinion: though not, perhaps, any stronger, I have become more
confident, and I think I have sufficient proofs, or at least probabilities, so
that even those who may not be of my opinion cannot blame me for
having written.
In general in the combustion of bodies four constant phenomena
are observable, which seem to be laws from which nature never departs.
Though these phenomena may be found implicitly stated in other me-
moirs, yet I cannot dispense with recalling them here in a few words.
First Phenomenon.
All combustion sets free matter either of fire or light.
Second Phenomenon.
Bodies can burn only in a very small number of kinds of gases
(airs), or rather there can be combustion only in one kind of air, that
which Mr. Priestley has named dephlogisticated air, and which I should
call pure air. Not only will the bodies which we call combustibles not
burn in a vacuum or in any other kind of air, they are, on the contrary,
extinguished there as promptly as if they had been plunged into water
or any other liquid.
Third Phenomenon.
In all combustion there is destruction or decomposition of the pure
EIGHTEENTH CENTURY SCIENCE 301
air in which the combustion takes place, and the body burned increases
in weight exactly in proportion to the quantity of air destroyed or
decomposed.
Fourth Phenomenon.
In all combustion the body burned changes to an acid by the addi-
tion of the substance which has increased its weight : thus, for example,
if sulphur is burned under a receiver the product of the combustion is
vitriolic acid; if phosphorus be burned the product is phosphoric acid;
if a carboniferous substance, the product is fixed air, otherwise known
as acid of lime (carbonic acid, etc.).
(Note : I would remark in passing that the number of acids is infin-
itely greater than has been supposed.)
The calcination of metals is subject to exactly the same laws, and
it is with very great reason that Mr. Macquer has treated it as a slow
combustion; thus, 1°, in all metallic combustion there is a liberating of
fire matter (matiere du feu) ; 2°, veritable calcination can take place only
in pure air ; 3°, there is a combination of the air with the substance cal-
cined, but with this difference, that in place of forming an acid with it
there results from it a particular combination known as metallic calx.
This is not the place to point out the analogy which exists between
the respiration of animals, combustion and calcination ; I shall return to
that in the sequel to this memoir.
These different phenomena of the calcination of metals and of
combustion are explained in a very happy manner by Stahl's hypothesis ;
but it is necessary with him to suppose the existence of fire matter (ma-
tiere du feu) or of fixed phlogiston in the metals, in sulphur and in all
bodies which he regards as combustibles ; yet if the partisans of Stahl's
doctrine are asked to prove the existence of fire matter in combustible
bodies, they fall necessarily into a vicious circle and are obliged to reply
that combustible bodies contain fire matter because they burn, and that
they burn because they contain fire matter. It is easy to see that in the
last analysis this is explaining combustion by combustion.
The existence of fire matter, or phlogiston, in metals, in sulphur,
etc., is then really only an hypothesis, a supposition, which, once admit-
ted, explains, it is true, some of the phenomena of calcination and com-
bustion ; but if I show that these very phenomena may be explained in
quite as natural a way by the opposite hypothesis, that is to say, without
supposing the existence of either fire matter or phlogiston in the sub-
stances called combustible, Stahl's system will be shaken to its founda-
tions.
302 EIGHTEENTH CENTURY SCIENCE
No doubt you will not fail to ask me first what I understand by fire
matter. I reply with Franklin, Boerhaave and some of the philosophers
of old, that the matter of fire or of light is a very subtle, very elastic
fluid, which surrounds every part of the planet we live on, which pene-
trates with more or less ease the substances which compose that, and
which tends, when it is free, to come to a state of equilibrium in all.
I will add, borrowing the chemical phraseology, that this fluid is the
solvent of a large number of substances ; that it combines with them in
the same way that water does with salt, and the acids with metals, and
that the bodies thus combined and dissolved by the igneous fluid lose in
part the properties which they had before the combination and acquire
new ones which bring them nearer (make them more like) the fire
matter.
It is thus, as I have shown in a memoir deposited with the secre-
tary of this Academy, that every aeriform fluid, every kind of air,
is a resultant of the combination of some substance, solid or fluid, with
the matter of fire or of light ; and it is to this combination that aeriform
fluids owe their elasticity, their specific volatility, their rarity, and all the
other properties which ally (rapprochent) them to the igneous fluid.
Pure air, according to this, what Mr. Priestley calls dephlogisti-
cated air, is an igneous compound into which the matter of fire or of
light enters as solvent, and into which some other substance enters as a
base; but if, in any solution whatever, a substance is presented to the
base with which that has greater affinity, it unites with this instantly and
the solvent which it leaves is set free.
The same thing happens with the air in combustion ; the substance
which burns steals away the base ; then the fire matter which served as
its solvent becomes free, regains its rights and escapes with the charac-
teristics by which we know it ; that is to say, with flame, heat and light.
To elucidate whatever may seem obscure in this theory let us apply
it to some examples : when a metal is calcined in pure air, the base of the
air, which has less affinity for its own solvent than for the metal, unites
with the latter as it melts and converts it into metallic calx. This combi-
nation of the base of the air with the metal is proved ist, by the increase
in weight which the latter undergoes in calcination ; 2nd, by the almost
total using up of the air under the receiving bell. But, if the base of
the air was held in solution by the fire-matter, in proportion as this base
combined with the metal, the fire-matter should become free and pro-
duce, in freeing itself, flame and light. You understand that the more
EIGHTEENTH CENTURY SCIENCE 303
speedy the calcination of the metal, that is to say, the more fixation of
the air takes place in a given time, the more fire-matter will be liberated,
and, consequently, the more marked and obvious the combustion will be.
* * * *
I might apply this theory successively to all combustions, but as I
shall have frequent occasion to return to this subject, I will content
myself at this time with these general illustrations. So, to resume, the
air is composed, according to my idea, of fire-matter as a dissolvent com-
bined with a substance which serves it as a base, and which in some way
neutralizes it ; whenever a substance for which it has a greater affinity
it brought into contact with this base, it leaves its solvent ; then the fire-
substance regains its rights, its properties, and appears to our eyes with
heat, flame and light.
Pure air, the dephlogisticated air of Mr. Priestley, is then, accord-
ing to this opinion, the real combustible body, and perhaps the only
one of that nature, and it is seen that it is no longer necessary, in order
to explain the phenomena of combustion, to suppose that there exists a
large quantity of fire fixed in all the substances which we call com-
bustible, but that it is very probable, on the contrary, that very little of it
exists in metals, in sulphur, phosphorus, and in most of the very solid,
heavy and compact bodies, and, perhaps, even that there exists in these
substances only free fire-matter, in virtue of the property which this
matter has of putting itself in equilibrium with all surrounding bodies.
Another striking reflection which comes to the support of the pre-
ceding ones, is that almost all substances may exist in three different
states : under a solid form, under a liquid form, that is to say melted,
or in the state of air or vapor. These three states depend solely on the
quantity, more or less, of fire-matter with which these substances are
interpenetrated and with which they are combined. Fluidity, vaporiza-
tion, elasticity, are then properties characteristic of the presence of fire
and of a great abundance of fire ; solidity, compactness, on the contrary,
are evidences of its absence. By so much then as it is demonstrated
that aeriform substances and air itself contain a large quantity of fire
in combination, by so much it is probable that solid bodies contain
little of it.
* * * *
For the rest, I repeat, in attacking here the doctrine of Stahl ; it was
not my purpose to substitute for it a rigorously demonstrated theory, but
only an hypothesis which seemed to me more probable, more in con-
304 EIGHTEENTH CENTURY SCIENCE
formity with the laws of nature, and one which appeared to involve less
forced explanations and fewer contradictions. — On Combustion, II. 225.
RESPIRATION A COMBUSTION
Respiration is a combustion, very slow, indeed, but otherwise pre-
cisely similar to that of carbon ; it takes place in the lungs, without pro-
ducing sensible light, because the fire-matter set free is at once absorbed
by the humidity of these organs ; the heat developed in this combustion
is communicated to the blood which traverses the lungs, and from there
is diffused throughout the entire animal system. Hence the air we
breathe serves two purposes equally necessary for our conservation ; it
removes from the blood the base of fixed air whose overabundance
would be very injurious; and the heat which this combination produces
in the lungs repairs the constant loss of heat which we experience
through the atmosphere and surrounding objects.
Animal heat is about the same in different parts of the body ; this
effect seems to depend on the three following causes : first, the rapidity
of the circulation of the blood, which promptly transmits even to the
extremities of the body the heat which it receives in the lungs ; the sec-
ond cause is the evaporation which the heat produces in these organs,
and which diminishes the degree of their temperature ; finally, the third
is connected with the increase observed in the specific heat of the
blood, when, by contact with pure air, it rids itself of the base of fixed
air which it contains ; a part of the specific heat developed in the forma-
tion of fixed air [carbonic acid gas] is thus absorbed by the blood, its
temperature remaining always the same; but when, in the circulation,
the blood takes up again the base of fixed air, its specific heat diminishes,
and heat is developed ; and, as this combination takes place in all parts of
the body, the heat which it produces contributes to maintaining the tem-
perature of parts distant from the lungs at about the same degree as that
of these organs. Furthermore, whatever may be the manner in which the
animal heat is kept up, that which is produced by the formation of fixed
air is its first cause ; hence we may establish the following proposition :
When an animal is in a permanent and tranquil state; when it can live
for a considerable time, without suffering, in the environment which
surrounds it; in general, when the circumstances in which it finds itself
do not sensibly impair its blood or its humors, so that after several
hours the animal system experiences no sensible variation; the con-
EIGHTEENTH CENTURY SCIENCE 305
sensation of the animal heat is due, at least in large part, to the heat
which the combination of the pure air respired by the animal with the
base of fixed air which the blood supplies to it, produces.
JAMES WATT
JAMES WATT was born at Greenock, Scotland, January 19, 1736. In
childhood he showed signs of an inventive ability and when a young
man learned to make mathematical instruments as a trade. In 1757 he
became instrument maker to the University of Glasgow. Not long
afterwards he was given a model of a Newcomen steam engine to repair
and was led to note its defects and eventually to his great invention.
In Newcomen's engine, which was used for pumping water from
mines, the steam was let into the bottom of a vertical cylinder. This
allowed the piston to be pulled up by a counterpoise at the farther end of
a beam. Then the boiler was disconnected, the steam in the cylinder
condensed by cold water, and the air forced the piston down, which lat-
ter action did the work of the engine. Watt was a friend of Joseph
Black, and learned from him that the fact that heat becomes latent in
changing water into steam, would cause a great loss of energy in
alternately cooling the cylinder in condensing the steam and in having to
heat it before the steam would force the piston to rise. Watt's process
of thought in overcoming the difficulty is given below. In brief, the
result was the condensation of the steam in a separate vessel.
The new engine was patented in 1769. In the meantime Watt had
become a surveyor and continued to make his living in this way until
the manufacture of his engines was at length put on a paying basis
under the firm of Boulton and Watt. His death was in 1819.
INVENTION OF THE STEAM ENGINE
My attention was first directed, in the year 1759, to the subject of
steam-engines, by the late Dr. Robison, then a student in the University
of Glasgow, and nearly of my own age. He at that time threw out an
306 EIGHTEENTH CENTURY SCIENCE
idea of applying the power of the steam-engine to the moving of wheel-
carriages, and to other purposes, but the scheme was not matured, and
was soon abandoned on his going abroad.
About the year 1761 or 1762 I tried some experiments on the force
of steam in a Papin's digester, and formed a species of steam-engine
by fixing upon it a syringe, one-third of an inch diameter, with a solid
piston, and furnished also with a cock to admit the steam from the di-
gester, or shut it off at pleasure, as well as to open a communication
from the inside of the syringe to the open air, by which the steam con-
tained in the syringe might escape. When the communication between
the digester and syringe was opened, the steam entered the syringe, and
by its action upon the piston raised a considerable weight (15 Ibs.) with
which it was loaded. When this was raised as high as was thought
proper, the communication with the digester was shut, and that with the
atmosphere opened; the steam then made its escape, and the weight
descended. The operations were repeated, and, though in this experi-
ment the cock was turned by hand, it was easy to see how it could be
done by the machine itself, and to make it work with perfect regularity.
But I soon relinquished the idea of constructing an engine upon its
principle, from being sensible it would be liable to some of the objec-
tions against Savery's engine, viz., the danger of bursting the boiler,
and the difficulty of making the joints tight, and also that a great part of
the power of the steam would be lost, because no vacuum was formed
to assist the descent of the piston. I, however, described this engine in
the fourth article of the specification of my patent of 1769 ; and again in
the specification of another patent in the year 1784, together with a mode
of applying it to the moving of wheel-carriages.
The attention necessary to the avocations of business prevented me
from then prosecuting the subject further, but in the winter of 1763-4,
having occasion to repair a model of Newcomen's engine belonging to
the Natural Philosophy class of the University of Glasgow, my mind
was again directed to it. At that period my knowledge was derived
principally from Desaguliers, and partly from Belidor. I set about
repairing it as a mere mechanician ; and when that was done, and it was
set to work, I was surprised to find that its boiler could not supply it
with steam, though apparently quite large enough, (the cylinder of the
model being two inches in diameter, and six inches stroke, and the
boiler about nine inches diameter). By blowing the fire it was made to
take a few strokes, but required an enormous quantity of injection
EIGHTEENTH CENTURY SCIENCE 307
water, though it was very lightly loaded by the column of water in the
pump. It soon occurred that this was caused by the little cylinder
exposing a greater surface to condense the steam, than the cylinders of
larger engines did in proportion to their respective contents. It was
found that by shortening the column of water in the pump, the boiler
could supply the cylinder with steam, and that the engine would work
regularly with a moderate quantity of injection. It now appeared that
the cylinder of the model, being of brass, would conduct heat much
better than the cast-iron cylinders of larger engines, (generally covered
on the inside with a stony crust,) and that considerable advantage could
be gained by making the cylinders of some substance that would receive
and give out heat slowly. Of these wood seemed to be the most likely,
provided it should prove sufficiently durable. A small engine was,
therefore, constructed, with a cylinder six inches diameter, and twelve
inches stroke, made of wood, soaked in linseed oil, and baked to dryness.
With this engine many experiments were made, but it was soon found
that the wooden cylinder was not likely to prove durable, and that the
steam condensed in filling it still exceeded the proportion of that re-
quired for large engines, according to the statements of Desaguliers.
It was also found that all attempts to produce a better exhaustion by
throwing in more injection, caused a disproportionate waste of steam.
On reflection, the cause of this seemed to be the boiling of water in vacuo
at low heats, a discovery lately made by Dr. Cullen and some other phil-
osophers, (below 100°, as I was then informed,) and consequently, at
greater heats, the water in the cylinder would produce a steam which
would, in part, resist the pressure of the atmosphere.
By experiments which I then tried upon the heats at which water
boils under several pressures greater than that of the atmosphere, it
appeared that when the heats proceeded in an arithmetical, the elas-
ticities proceeded in some geometrical ratio; and, by laying down a
curve from my data, I ascertained the particular one near enough for my
purpose. It also appeared that any approach to a vacuum could only be
obtained by throwing in large quantities of injection, which would cool
the cylinder so much as to require quantities of steam to heat it again,
out of proportion to the power gained by the more perfect vacuum, and
that the old engineers had acted wisely in contenting themselves with
loading the engine with only six or seven pounds on each square inch
of the area of the piston. It being evident that there was a great error
in Dr. Desaguliers' calculations of Mr. Beighton's experiments on the
308 EIGHTEENTH CENTURY SCIENCE
bulk of steam, a Florence flask, capable of containing about a pound of
water, had about one ounce of distilled water put into it ; a glass tube
was fitted into its mouth, and the joining made tight by lapping that
part of the tube with pack-thread, covered with glazier's putty. Wheii
the flask was set upright, the tube reached down near to the surface of
the water, and in that position the whole was placed in a tin reflecting
oven before a fire, until the water was wholly evaporated, which hap-
pened in about an hour, and might have been done sooner had I not
wished the heat not much to exceed that of boiling water. As the air
in the flask was heavier than the steam, the latter ascended to the top,
and expelled the air through the tube. When the water was all evap-
orated, the oven and flask were removed from the fire, and a blast of cold
air was directed against one side of the flask, to collect the condensed
steam in one place. When all was cold, the tube was removed, the flask
and its contents were weighed with care, and the flask being made hot,
it was dried by blowing into it by bellows, and, when weighed again, was
found to have lost rather more than 4 grains, estimated at 4 1-3 grains.
When the flask was filled with water, it was found to contain about 17^
ounces avoirdupois of that fluid, which gave about 1800 for the expan-
sion of water converted into steam of the heat of boiling water.
This experiment was repeated with nearly the same result, and in
order to ascertain whether the flask had been wholly filled with steam,
a similar quantity of water was for the third time evaporated, and, while
the flask was still cold, it was placed inverted, with its mouth (contracted
by the tube) immersed in a vessel of water, which it sucked in as it
cooled, until in the temperature of the atmosphere it was filled to within
half an ounce measure of water. In the contrivance of this experiment I
was assisted by Dr. Black. In Dr. Robison's edition of Dr. Black's lec-
tures, vol. i., p. 147, the latter hints at some experiments upon this sub-
ject, as made by him, but I have no knowledge of any except those which
I made myself.
In repetitions of this experiment at a later date, I simplified the
apparatus by omitting the tube and laying the flask upon its side in the
oven, partly closing its mouth by a cork, having a notch on one side, and
otherwise proceeding as has been mentioned.
I do not consider these experiments as extremely accurate, the only
scale-beam of a proper size which I had then at my command not being
very sensible, and the bulk of the steam being liable to be influenced
by the heat to which it is exposed, which, in the way described, is not
EIGHTEENTH CENTURY SCIENCE 309
easily regulated or ascertained ; but, from my experience in actual prac-
tice, I esteem the expansion to be rather more than I have computed.
A boiler was constructed which showed, by inspection, the quan-
tity of water evaporated in any given time, and thereby ascertained the
quantity of steam used in every stroke by the engine, which I found to
be several times the full of the cylinder. Astonished at the quantity of
water required for the injection, and the great heat it had acquired from
the small quantity of water in the form of steam which had been used
in filling the cylinder, and thinking I had made some mistake, the fol-
lowing experiment was tried : — A glass tube was bent at right angles ;
one end was inserted horizontally into the spout of a tea-kettle, and the
other part was immersed perpendicularly in well-water contained in a
cylindric glass vessel, and steam was made to pass through it until it
ceased to be condensed, and the water in the glass vessel was become
nearly boiling hot. The water in the glass vessel was then found to have
gained an addition of about one-sixth part from the condensed steam.
Consequently, water converted into steam can heat about six times its
own weight of well-water to 212°, or till it can condense no more steam.
Being struck with this remarkable fact, and not understanding the
reason of it, I mentioned it to my friend Dr. Black, who then explained
to me his doctrine of latent heat, which he had taught for some time
before this period, (summer 1764,) but having myself been occupied
with the pursuits of business, if I had heard of it, I had not attended to
it, when I thus stumbled upon one of the material facts by which that
beautiful theory is supported.
On reflecting further I perceived that, in order to make the best use
of steam, it was necessary — first, that the cylinder should be maintained
always as hot as the steam which entered it ; and, secondly, that when the
steam was condensed, the water of which it was composed, and the in-
jection itself, should be cooled down to 100°, or lower, where that was
possible. The means of accomplishing these points did not immediately
present themselves, but early in 1765 it occurred to me, that if a com-
munication were opened between a cylinder containing steam and an-
other vessel which was exhausted of air and other fluids, the steam, as
an elastic fluid, would immediately rush into the empty vessel, and con-
tinue so to do until it had established an equilibrium, and if that vessel
were kept very cool by an injection, or otherwise, more steam would
continue to enter until the whole was condensed. But both the vessels
being exhausted, or nearly so, how were the injection-water, the air
310 EIGHTEENTH CENTURY SCIENCE
which would enter with it, and the condensed steam, to be got out?
This I proposed, in my own mind, to perform in two ways. One was,
by adapting to the second vessel a pipe, reaching downwards more than
34 feet, by which the water would descend, (a column of that length
overbalancing the atmosphere,) and by extracting the air by means of a
pump.
The second method was by employing a pump, or pumps, to extract
both the air and the water, which would be applicable in all places, and
essential in those cases where there was no well or pit.
This latter method was the one I then preferred, and is the only one
I afterwards continued to use.
In Newcomen's engine the piston is kept tight by water, which
could not be applicable in this new method ; as, if any of it entered into
a partially exhausted and hot cylinder, it would boil, and prevent the
production of a vacuum, and would also cool the cylinder by its evapora-
tion during the descent of the piston. I proposed to remedy this defect
by employing wax, tallow, or other grease, to lubricate and keep the
piston tight. It next occurred to me that, the mouth of the cylinder
being open, the air which opened to act on the piston would cool the
cylinder, and condense some steam on again filling it. I therefore pro-
posed to put an air-tight cover upon the cylinder, with a hole and
stuffing-box for the piston to slide through, and to admit steam above the
piston to act upon it, instead of the atmosphere. The piston-rod sliding
through a stuffing-box was new in steam-engines ; it was not necessary
in Newcomen's engine, as the mouth of the cylinder was open, and the
piston-rod was square and very clumsy. The fitting the piston-rod to
the piston by a cone was an after improvement of mine, (about 1774).
There still remained another source of the destruction of steam, the
cooling of the cylinder by the external air, which would produce an
internal condensation whenever steam entered it, and which would be
repeated every stroke ; this I proposed to remedy by an external cylinder,
containing steam, surrounded by another of wood, or of some other sub-
stance which would conduct heat slowly.
When once the idea of the separate condensation was started, all
these improvements followed as corollaries in quick succession, so that
in the course of one or two days the invention was thus far complete in
my mind, and I immediately set about an experiment to verify it prac-
tically. I took a large brass syringe, if inches diameter and 10 inches
long, made a cover and bottom to it of tin-plate, with a pipe to convey
EIGHTEENTH CENTURY SCIENCE 311
steam to both ends of the cylinder from the boiler; another pipe to
convey steam from the upper end to the condenser, (for, to save ap-
paratus, I inverted the cylinder ;) I drilled a hole longitudinally through
the axis of the stem of the piston, and fixed a valve at its lower end, to
permit the water, which was produced by the condensed steam on first
filling the cylinder, to issue. The condenser used upon this occasion
consisted of two pipes of thin tin-plate, ten or twelve inches long, and
about one-sixth inch diameter, standing perpendicular, and communicat-
ing at top with a short horizontal pipe of large diameter, having an
aperture on its upper side, which was shut by a valve opening upwards.
These pipes were joined at bottom to another perpendicular pipe of
about an inch diameter, which served for the air and water-pump, and
both the condensing pipes and the air-pump were placed in a small cis-
tern filled with cold water. This construction of the condenser was
employed from knowing that heat penetrated thin plates of metal very
quickly, and considering that if no injection was thrown into an ex-
hausted vessel, there would be only the water of which the steam had
been composed, and the air which entered with the steam, or through the
leaks, to extract.
The steam-pipe was adjusted to a small boiler. When steam was
produced, it was admitted into the cylinder, and soon issued through the
perforation of the rod, and at the valve of the condenser. When it was
judged that the air was expelled, the steam-cock was shut, and the air-
pump piston-rod was drawn up, which leaving the small pipes of the
condenser in a state of vacuum, the steam entered them and was con-
densed. The piston of the cylinder immediately rose, and lifted a weight
of about 18 Ibs., which was hung to the lower end of the piston-rod.
The exhaustion-cock was shut, the steam was readmitted into the cylin-
der, and the operation was repeated ; the quantity of steam consumed,
and the weights it could raise, were observed, and, excepting the non-
application of the steam-case and external covering, the invention
was complete, in so far as regarded the savings of steam and fuel. A
large model, with an outer cylinder and wooden case, was immediately
constructed, and the experiments made with it served to verify the
expectations I had formed, and to place the advantage of the invention
beyond the reach of doubt. It was found convenient afterwards to
change the pipe-condenser for an empty vessel, generally of a cylin-
drical form, into which an injection played, and, in consequence of there
being more water and air to extract, to enlarge the air-pump.
312 EIGHTEENTH CENTURY SCIENCE
The change was made because, in order to procure a surface suffi-
ciently extensive to condense the steam of a large engine, the pipe-con-
denser would require to be very voluminous, and because the bad water
with which engines are frequently supplied would crust over the thin
plates, and prevent their conveying the heat sufficiently quick. The
cylinders were also placed with their mouths upwards, and furnished
with a working-beam and other apparatus, as was usual in the ancient
engines ; the inversion of the cylinder, or rather of the piston-rod, in the
model, being only an expedient to try more easily the new invention,
and being subject to many objections in large engines.
In 1768 I applied for letters patent for my "Methods of Lessening
the Consumption of Steam, and, consequently, of Fuel, in Fire-
Engines," which passed the seals in January, 1769; and my Specification
was enrolled in Chancery in April following.
HUTTON
JAMES HUTTON was born in Edinburgh in 1726. He studied in
that city, then traveled in Europe and finally took his medical degree in
1749. In the same year he returned to England to practice, but gave it
up the next year for agriculture. At this time he became interested
in the structure of the earth.
Anyone that has read Ovid will remember the old Pythagorean
view of geology.
In 1519 Leonardo da Vinci and in 1580 Palissy in Paris wrote
against the prevalent idea that the earth had always remained as it was,
and that fossils were stones ready made by nature, but the old idea held
its own until the last century. Leibnitz in 1680 propounded the theory
that the earth was once a luminous burning mass. But geology was
held back by the fear of conflicting with the Mosaic doctrine of the
earth's creation. In the last quarter of the eighteenth century Werner,
Professor of Mineralogy at Freiburg, Germany, developed his doctrine
of the formation of the strata by precipitation from the ocean. He
believed that such rocks as granite (the chemical rocks) were first
made and are the bases of all others.
EIGHTEENTH CENTURY SCIENCE 313
Hutton found evidences of volcanic origin and the production of
rock from a fused state. He taught that materials laid down and com-
pressed by the sea were upheaved by central heat, and that they were
subsequently gradually worn away by the action of the weather. His
doctrine "In the economy of the world, I can find no traces of a begin-
ning, no prospect of an end," brought him into disrepute with theology.
A violent quarrel arose between the Neptunists (followers of Werner)
and the Vulcanists (followers of Hutton), that raged until the time of
Lyell.
Hutton died in 1797. With his rival, Werner, he opened up the
way in geology. His system owed its extension and popularity largely
to the brilliant account of it by his friend John Playfair, Professor of
Mathematics in Edinburgh.
BUTTON'S THEORY OF THE PHENOMENA COMMON TO
STRATIFIED AND UNSTRATIFIED BODIES
The series of changes which fossil bodies are destined to undergo,
does not cease with their elevation above the level of the sea ; it assumes,
however, a new direction, and from the moment that they are raised up
to the surface, is constantly exerted in reducing them again under the
dominion of the ocean. The solidity is now destroyed ' which was
acquired in the bowels of the earth ; and as the bottom of the sea is the
great laboratory, where loose materials are mineralized and formed into
stone, the atmosphere is the region where stones are decomposed, and
again resolved into earth.
This decomposition of all mineral substances, exposed to the air, is
continual, and is brought about by a multitude of agents, both chemical
and mechanical, of which some are known to us, and many, no doubt,
remain to be discovered. Among the various aeriform fluids which
compose our atmosphere, one is already distinguished as the grand prin-
ciple of mineral decomposition ; the others are not inactive, and to them
we must add moisture, heat, and perhaps light ; substances which, from
their affinities to the elements of mineral bodies, have a power of enter-
ing into combination with them, and of thus diminishing the forces by
which they are united to one another. By the action of air and mois-
ture, the metallic particles, particularly the iron, which enters in great
abundance into the composition of almost all fossils, becomes oxydated
V 6-20
314 EIGHTEENTH CENTURY SCIENCE
in such a degree as to lose its tenacity ; so that the texture of the sur-
face is destroyed, and a part of the body resolved into earth.
Some earths, again, such as the calcareous, are immediately dis-
solved by water; and though the quantity so dissolved be extremely
small, the operation, by being continually renewed, produces a slow but
perpetual corrosion, by which the greatest rocks must in time be sub-
dued. The action of water in destroying hard bodies into which it has
obtained entrance, is much assisted by the vicissitudes of heat and cold,
especially when the latter extends as far as the point of congelation;
for the water when frozen, occupies a greater space than before, and if
the body is compact enough to refuse room for this expansion, its parts
are torn asunder by a repulsive force acting in every direction.
Beside these causes of mineral decomposition, the action of which
we can in some measure trace, there are others known to us only by
their effects.
We see, for instance, the purest rock crystal affected by exposure
to the weather, its lustre tarnished, and the polish of its surface im-
paired, but we know nothing of the power by which these operations
are performed. Thus also, in the precautions which the mineralogist
takes to preserve the fresh fracture of his specimens, we have a proof
how indiscriminately all the productions of the animal kingdom are
exposed to the attacks of their unknown enemies, and we perceive how
difficult it is to delay the beginnings of a process which no power what-
ever can finally counteract.
The mechanical forces employed in the disintegration of mineral
substances, are more easily marked than the chemical. Here again
water appears as the most active enemy of hard and solid bodies ; and,
in every state, from transparent vapour to solid ice, from the smallest
rill to the greatest river, it attacks whatever has emerged above the level
of the sea, and labours incessantly to restore it to the deep. The parts
loosened and disengaged by the chemical agents, are carried down by
the rains, and, in their descent, rub and grind the superficies of other
bodies. Thus water, though incapable of acting on hard substances by
direct attrition, is the cause of their being so acted on; and, when it
descends in torrents, carrying with it sand, gravel, and fragments of
rock, it may be truly said to turn the forces of the mineral kingdom
against itself. Every separation which it makes is necessarily per-
manent, and the parts once detached can never be united, save at the
bottom of the ocean.
EIGHTEENTH CENTURY SCIENCE 315
But it would far exceed the limits of this sketch, to pursue the
causes of mineral decomposition through all their forms. It is suffi-
cient to remark, that the consequence of so many minute, but inde-
fatigable agents, all working together, and having gravity in their
favour, is a system of universal decay and degradation, which may be
traced over the whole surface of the land, from the mountain top to the
sea shore. That we may perceive the full evidence of this truth, one of
the most important in the natural history of the globe, we will begin
our survey from the latter of these stations, and retire gradually toward
the former.
If the coast is bold and rocky, it speaks a language easy to be inter-
preted. Its broken and abrupt contour, the deep gulfs and salient
promontories by which it is indented, and the proportion which these
irregularities bear to the force of the waves, combined with the in-
equality of hardness in the rocks, prove, that the present line of shore
has been determined by the action of the sea. The naked and precip-
itous cliffs which overhang the deep, the rocks hollowed, perforated, as
they are farther advanced in the sea, and at last insulated, lead to the
same conclusion, and mark very clearly so many different stages of
decay. It is true, we do not see the successive steps of this progress
exemplified in the states of the same individual rock, but we see them
clearly in different individuals ; and the conviction thus produced, when
the phenomena are sufficiently multiplied and varied, is as irresistible,
as if we saw the changes actually effected in the moment of observation.
On such shores, the fragments of rock once detached, become in-
struments of further destruction, and make a part of the powerful artil-
lery with which the ocean assails the bulwarks of the land : they are
impelled against the rocks, from which they break off other fragments,
and the whole are thus ground against one another ; whatever be their
hardness, they are reduced to gravel, the smooth surface and round
figure of which, are the most certain proofs of a detritus which nothing
can resist.
Again, where the sea coast is flat, we have abundant evidence of
the degradation of the land in the beaches of sand and small gravel ; the
sand banks and shoals that are constantly changing; the alluvial land
at the mouths of the rivers ; the bars that seem to oppose their discharge
into the sea, and the shallowness of the sea itself. On such coasts, the
land usually seems to gain upon the sea, whereas, on shores of a bolder
aspect, it is the sea that generally appears to gain upon the land. What
316 EIGHTEENTH CENTURY SCIENCE
the land acquires in extent, however, it loses in elevation ; and, whether
its surface increase or diminish, the depredations made on it are in both
cases evinced with equal certainty.
If we proceed in our survey from the shores, inland, we meet
at every step with the fullest evidence of the same truths, and particu-
larly in the nature and economy of rivers. Every river seems to con-
sist of a main trunk, fed from a variety of branches, each running in a
valley proportioned to its size, and all of them together forming a sys-
tem of valleys, communicating with one another, and having such a nice
adjustment of their declivities, that none of them join the principal
valley, either on too high or too low a level; a circumstance which
would be infinitely improbable, if each of these valleys were not the
work of the stream that flows in it.
If indeed a river consisted of a single stream, without branches,
running in a straight valley, it might be supposed that some great con-
cussion, or some powerful torrent, had opened at once the channel by
which its waters are conducted to the ocean ; but, when the usual form
of a river is considered, the trunk divided into many branches, which
rise at a great distance from one another, and these again subdivided
into an infinity of smaller ramifications, it becomes strongly impressed
upon the mind, that all these channels have been cut by the waters
themselves; that they have been slowly dug out by the washing and
erosion of the land ; and that it is by the repeated touches of the same
instrument, that this curious assemblage of lines has been engraved so
deeply on the surface of the globe.
The changes which have taken place in the courses of rivers, are
also to be traced, in many instances, by successive platforms, of flat
alluvial land, rising one above another, and marking the different levels
on which the river has run at different periods of time. Of these, the
number to be distinguished, in some instances, is not less than four, or
even five; and this necessarily carries us back, like all the operations
we are now treating of, to an antiquity extremely remote : for, if it be
considered, that each change which the river makes in its bed, obliterates
at least a part of the monuments of former changes, we shall be con-
vinced, that only a small part of the progression can leave any distinct
memorial behind it, and that there is no reason to think, that, in the
part which we see, the beginning is included.
In the same manner, when a river undermines its banks, it often
discovers deposits of sand and gravel, that have been made when it ran
EIGHTEENTH CENTURY SCIENCE 317
on a higher level than it does at present. In other instances, the same
strata are seen on both the banks, though the bed of the river is now
sunk deep between them, and perhaps holds as winding a course through
the solid rock, as if it flowed along the surface; a proof that it must
have begun to sink its bed, when it ran through such loose materials as
opposed but a very inconsiderable resistance to its stream. A river, of
which the course is both serpentine and deeply excavated in the rock, is
among the phenomena, by which the slow waste of the land, and also
the cause of that waste, are most directly pointed out.
It is, however, where rivers issue through narrow defiles among
mountains, that the identity of the strata on both sides is most easily
recognized, and remarked at the same time with the greatest wonder.
On observing the Potomack, where it penetrates the ridge of the Ale-
gany mountains, or the Irtish, as it issues from the defiles of Altai,
there is no man, however little addicted to geological speculations, who
does not immediately acknowledge that the mountain was once continued
quite across the space in which the river now flows ; and if he ventures
to reason concerning the cause of so wonderful a change, he ascribes
it to some great convulsion of nature, which has torn the mountain
asunder, and opened a passage for the waters. It is only the philos-
opher, who has deeply meditated on the effects which action long con-
tinued is able to produce, and on the simplicity of the means which
nature employs in all her operations, who sees in this nothing but the
gradual working of a stream, that once flowed over the top of the ridge
which it now intersects, and has cut its course through the rock, in the
same way, and almost with the same instrument, by which 'the lapidary
divides a block of marble or granite.
It is highly interesting to trace up, in this manner, the action of
causes with which we are familiar, to the production of effects, which
at first seem to require the introduction of unknown and extraordinary
powers; and it is no less interesting to observe, how skilfully nature
has balanced the action of all the minute causes of waste, and rendered
them conducive to the general good. Of this we have a most remark-
able instance, in the provision made for preserving the soil, or the coat
of vegetable mould spread out over the surface of the earth. This coat,
as it consists of loose materials, is easily washed away by the rains, and
is continually carried down by the rivers into the sea. This effect is
visible to every one ; the earth is removed not only in the form of sand
and gravel, but its finer particles suspended in the waters, tinge those
318 EIGHTEENTH CENTURY SCIENCE
of some rivers continually, and those of all occasionally, that is, when
they are flooded or swollen with rains. The quantity of earth thus
carried down, varies according to circumstances ; it has been computed,
in some instances, that the water of a river in a flood, contains earthy
matter suspended in it, amounting to more than the two hundred and fif-
tieth part of its own bulk. The soil, therefore, is continually diminished,
its parts being transported from higher to lower levels, and finally de-
livered into the sea. But it is a fact, that the soil, notwithstanding,
remains the same in quantity, or at least nearly the same, and must have
done so, ever since the earth was the receptacle of animal or vegetable
life. The soil, therefore, is augmented from other causes, just as much,
at an average, as it is diminished by that now mentioned ; and this aug-
mentation evidently can proceed from nothing but the constant and slow
disintegration of the rocks. In the permanence, therefore, of a coat of
vegetable mould on the surface of the earth, we have a demonstrative
proof of the continual destruction of the rocks ; and cannot but admire
the skill with which the powers of the many chemical and mechanical
agents employed in this complicated work, are so adjusted, as to make
the supply and the waste of the soil exactly equal to one another.
Before we take leave of the rivers and the plains, we must remark
another fact, often observed in the natural history of the latter, and
clearly evincing the former existence of immense bodies of strata, in
situations from which they have now entirely disappeared. The fact
here alluded to is, the great quantity of round and hard gravel, often to
be met with in the soil, under such circumstances, as prove, that it can
only have come from the decomposition of rocks, that once occupied the
very ground over which this gravel is now spread. In the chalk coun-
try, for instance, about London, the quantity of flints in the soil is every
where great; and, in particular situations, nothing but flinty gravel is
found to a considerable depth. Now, the source from which these flints
are derived is quite evident, for they are precisely the same with those
contained in the chalk beds, wherever these last are found undisturbed,
and from the destruction of such beds they no doubt originated. Hence
a great thickness of chalk must have been decomposed, to yield the
quantities of flints now in the soil of these countries ; for the flints are
but thinly scattered through the native chalk, compared with their
abundance in the loose earth. To afford, for example, such a body of
flinty gravel as is found about Kensington, what an enormous quantity
of chalk rock must have been destroyed ?
EIGHTEENTH CENTURY SCIENCE 319
This argument, which Dr. Hutton has applied particularly to the
chalk countries, may be extended to many others. The great plain of
Crau, near the mouth of the Rhone, is well known, and is regarded
with wonder, even in ages when the natural history of the globe was
not an object of much attention. The immense quantity of large round
gravel stones, with which this extensive plain is entirely covered, has
been supposed, by some mineralogists, to have been brought down by
the Durance, and other torrents, from the Alps ; but, on further exam-
ination, has been found to be of the same kind that is contained in cer-
tain horizontal layers of pudding-stone, which are the basis of the
whole plain. It cannot be doubted, therefore, that the vast body of
gravel spread over it, has originated from the destruction of layers of
the same rock, which may perhaps have risen to a great height above
what is now the surface. Indeed, from knowing the depth of the
gravel that covers the plain, and the average quantity of the like gravel
contained in a given thickness of rock, one might estimate how much of
the latter has been actually worn away. Whether data precise enough
could be found, to give any weight to such a computation, must be left
for future inquiry to determine.
In these instances, chalk and pudding-stone, by containing in them-
selves parts infinitely less destructible than their general mass, have,
after they are worn away, left behind them very unequivocal marks of
their existence. The same has happened in the case of mineral veins,
where the substances least subject to dissolution have remained, and are
scattered at a great distance from their native place. Thus gold, the
least liable to decomposition of all the metals, is very generally diffused
through the earth, and is found, in a greater or less abundance, in the
sand of almost all rivers. But the native place of this mineral is the solid
rock, and from thence it must have made its way into the soil. This,
therefore, is another proof of the vast extent to which the degradation of
the land, and of the rock, which is the basis of it, has been carried ; and
consequently, of the great difference between the elevation and shape of
the earth's surface in the present, and in former ages.
The veins of tin furnish an argument of the same kind. The ores
of this metal are very indestructible, and little subject to decomposition,
so that they remain very long in the ground without change. Where
there are tin veins, as in Cornwall, the tin-stone or tin ore is found in
great abundance in such vallies or streams as have the same direction
with the veins ; and hence the streaming, as it is called, or washing of
320 EIGHTEENTH CENTURY SCIENCE
the earth, to obtain the tin-stone from it. Now, if it be considered, that
none of this ore can have come into the soil but from parts of a vein
actually destroyed, it must appear evident that a great waste of these
veins has taken place, and consequently of the schistus or granite in
which they are contained.
These lessons, which the geologist is taught in flat and open coun-
tries, become more striking, by the study of those Alpine tracts, where
the surface of the earth attains its greatest elevation. If we suppose
him placed for the first time in the midst of such a scene, as soon as he
has recovered from the impression made by the novelty and magnifi-
cence of the spectacle before him, he begins to discover the footsteps of
time, and to perceive, that the works of nature, usually deemed the most
permanent, are those on which the characters of vicissitude are most
deeply imprinted. He sees himself in the midst of a vast ruin, where the
precipices which rise on all sides with such boldness and asperity, the
sharp peaks of the granite mountains, and the huge fragments that sur-
round their bases, do but mark so many epochs in the progress of decay,
and point out the energy of those destructive causes, which even the
magnitude and solidity of such great bodies have been unable to resist.
The result of a more minute investigation, is in perfect unison with
this general impression. Whence is it, that the elevation of mountains
is so obviously connected with the hardness and indestructibility of
the rocks which compose them? Why is it, that a lofty mountain of
soft and secondary rock is nowhere to be found ; and that such chains,
as the Pyrenees or the Alps, never consist of any but the hardest stone,
of granite, for instance, or of those primary strata, which, if we are to
credit the preceding theory, have been twice heated in the fires, and
twice tempered in the waters, of the mineral regions? Is it not plain
that this arises, not from any direct connection between the hardness
of stones, and their height in the atmosphere, but from this, that the
waste and detritus to which all things are subject, will not allow soft
and weak substances to remain long in an exposed and elevated situa-
tion? Were it not for this, the secondary rocks would be in position
superincumbent on the primary, (as they no doubt have at one time
been,) in the highest as well as the lowest situations, or among the
mountains as well as the plains.
Again, wherefore is it, that among all mountains, remarkable for
their ruggedness and asperity, the rock, on examination, is always
found of very unequal destructibility, some parts yielding to the
EIGHTEENTH CENTURY SCIENCE 321
weather, and to the other causes of disintegration, much more slowly
than the rest, and having strength sufficient to support themselves, when
left alone, in slender pyramids, bold projections, and overhanging cliffs?
Where, on the other hand, the rock wastes uniformly, the mountains are
similar to one another ; their swells and slopes are gentle, and they are
bounded by a waving and continuous surface. The intermediate de-
grees of resistance which the rocks oppose to the causes of destruction,
produce intermediate forms. It is this which gives to the mountains, of
every different species of rock, a different habit and expression, and
which, in particular, has imparted to those of granite that venerable
and majestic character, by which they rarely fail to be distinguished.
The structure of the vallies among the mountains, shows clearly
to what cause their existence is to be ascribed. Here we have first a
large valley, communicating directly with the plain, and winding be-
tween high ridges of mountains, while the river in the bottom of it de-
scends over a surface, remarkable, in such a scene, for its uniform
declivity. Into this, open a multitude of transverse or secondary val-
lies, intersecting the ridges on either side of the former, each bringing a
contribution to the main stream, proportioned to its magniture ; and, ex-
cept where a cataract now and then intervenes, all having that nice
adjustment in their levels, which is the more wonderful, the greater
the irregularity of the surface. These secondary vallies have others of
a smaller size opening into them; and, among mountains of the first
order, where all is laid out on the greatest scale, these ramifications are
continued to a fourth, and even a fifth, each diminishing in size as it
increases in elevation, and as its supply of water is less. Through them
all this law is in general observed, that where a higher valley joins a
lower one, of the two angles which it makes with the latter, that which
is obtuse is always on the descending side ; a law that is the same with
that which regulates the confluence of streams running on a surface
nearly of uniform inclination. This alone is a proof that the vallies are
the work of the streams; and indeed what else but the water itself,
working its way through obstacles of unequal resistance, could have
opened or kept up a communication between the inequalities of an ir-
regular and alpine surface?
Many more arguments, all leading to the same conclusion, may be
deduced from the general facts, known in the natural history of moun-
tains; and, if the Oreologist would trace back the progress of waste,
till he come in sight of that original structure, of which the remains are
322 EIGHTEENTH CENTURY SCIENCE
still so vast, he perceives an immense mass of solid rock, naked and
unshapely, as it first emerged from the deep, and incomparably greater
than all that is now before him. The operation of rains and torrents,
modified by the hardness and tenacity of the rock, has worked out the
whole into its present form ; has hollowed out the vallies, and gradually
detached the mountains from the general mass, cutting down their sides
into steep precipices at one place, and smoothing them into gentle decliv-
ities at another. From this has resulted a transportation of materials,
which, both for the quantity of the whole, and the magnitude of the
individual fragments, must seem incredible to every one, who has not
learned to calculate the effects of continued action, and to reflect, that
length of time can convert accidental into steady causes. Hence frag-
ments of rock, from the central chain, are found to have travelled into
distant vallies, even where many inferior ridges intervene: hence the
granite of Mont Blanc is seen in the plains of Lombardy, or on the
sides of Jura ; and the ruins of the Carpathian mountains lie scattered
over the shores of the Baltic.
Thus, with Dr. Hutton, we shall be disposed to consider those great
chains of mountains, which traverse the surface of the globe, as cut
out of masses vastly greater, and more lofty than any thing that now
remains. The present appearances afford no data for calculating the
original magnitude of these masses, or the height to which they may
have been elevated. The nearest estimate we can form is, where a
chain or group of mountains, like those of Bosa in the Alps, is horizon-
tally stratified, and where, of consequence, the undisturbed position of
the mineral beds enables us to refer the whole of the present inequal-
ities of the surface to the operation of waste or decay. These moun-
tains, as they now stand, may not inaptly be compared to the pillars of
earth which workmen leave behind them, to afford a measure of the
whole quantity of earth which they have removed. As the pillars,
(considering the mountains as such,) are in this case of less height
than they originally were, so the measure furnished by them is but a
limit, which the quantity sought must necessarily exceed.
Such, according to Dr. Hutton's theory, are the changes which the
daily operations of waste have produced on the surface of the globe.
These operations, inconsiderable if taken separately, become great, by
inspiring all to the same end, never counteracting one another, but pro-
ceeding, through a period of indefinite extent, continually in the same
direction. Thus every thing descends, nothing returns upward; the
EIGHTEENTH CENTURY SCIENCE 323
hard and soft bodies every where dissolve, and the loose and soft no
where consolidate. The powers which tend to preserve, and those
which tend to change the condition of the earth's surface, are never in
equilibrio ; the latter are, in all cases, the most powerful, and, in respect
of the former, are like living in comparison of dead forces. Hence the
law of decay is one which suffers no exception : The elements of all
bodies were once loose and unconnected, and to the same state nature
has appointed that they should all return.
It affords no presumption against the reality of this progress, that,
in respect of man, it is too slow to be immediately perceived. The ut-
most portion of it to which our experience can extend, is evanescent, in
comparison with the whole, and must be regarded as the momentary
increment of a vast progression, circumscribed by no other limits than
the duration of the world. Time performs the office of integrating the
infinitesimal parts of which this progression is made up; it collects
them into one sum, and produces from them an amount greater than
any that can be assigned.
While on the surface of the earth so much is every where going to
decay, no new production of mineral substances is found in any re-
gion accessible to man. The instances of what are called petrifactions,
or the formation of stony substances by means of water, which we some-
times observe, whether they be ferruginous concretions, or calcareous,
or, as happens in some rare cases, siliceous stalactites, are too few in
number and too inconsiderable in extent, to be deemed material excep-
tions to this general rule. The bodies thus generated, also, are no
sooner formed, than they become subject to waste and dissolution, like
all the other hard substances in nature; so that they but retard for a
while the progress by which they are all resolved into dust, and sooner
or later committed to the bosom of the deep.
We are not, however, to imagine, that there is nowhere any means
of repairing this waste; for, on comparing the conclusion at which
we are now arrived, viz. that the present continents are all going to
decay, and their materials descending into the ocean, with the proposi-
tion first laid down, that these same continents are composed of mate-
rials which must have been collected from the decay of former rocks,
it is impossible not to recognise two corresponding steps of the same
progress ; of a progress, by which mineral substances are subjected to
the same series of changes, and alternately wasted away and renovated.
In the same manner, as the present mineral substances derive their
324 EIGHTEENTH CENTURY SCIENCE
origin from substances similar to themselves; so, from the land now
going to decay, the sand and gravel forming on the sea shore, or in the
beds of rivers ; from the shells and corals, which in such enormous quan-
tities are every day accumulated in the bosom of the sea ; from the drift
wood, and the multitude of vegetable and animal remains continually
deposited in the ocean : from all these we cannot doubt, that strata are
now forming in those regions, to which nature seems to have confined
the powers of mineral reproduction; from which, after being consoli-
dated, they are again destined to emerge, and to exhibit a series of
changes similar to the past.
How often these vicissitudes of decay and renovation have been
repeated, is not for us to determine ; they constitute a series, of which,
as the author of this theory has remarked, we neither see the beginning
nor the end ; a circumstance that accords well with what is known con-
cerning other parts of the economy of the world. In the continuation of
the different species of animals and vegetables that inhabit the earth,
we discern neither a beginning nor an end ; and, in the planetary mo-
tions, where geometry has carried the eye so far both into the future
and the past, we discover no mark, either of the commencement or
the termination of the present order. It is unreasonable, indeed, to
suppose, that such marks should any where exist. The Author of na-
ture has not given laws to the universe, which like the institutions of
men, carry in themselves the elements of their own destruction. He
has not permitted, in his works, any symptom of infancy or of old age,
or any sign by which we may estimate either their future or their past
duration. He may put an end, as he no doubt gave a beginning, to the
present system, at some determinate period ; but we may safely conclude,
that this great catastrophe will not be brought about by any of the laws
now existing, and that it is not indicated by any thing which we perceive.
To assert, therefore, that, in the economy of the world, we see no
mark, either of a beginning or an end, is very different from affirming,
that the world had no beginning, and will have no end. The first is a
conclusion justified by common sense, as well as sound philosophy ; while
the second is a presumptuous and unwarrantable assertion, for which no
reason from experience or analogy can ever be assigned. Dr. Hutton
might, therefore, justly complain of the uncandid criticism, which, by
substituting the one of these assertions for the other, endeavoured to
load his theory with the reproach of atheism and impiety. Mr. Kir-
wan, in bringing forward this harsh and ill-founded censure, was neither
EIGHTEENTH CENTURY SCIENCE 325
animated by the spirit, nor guided by the maxims of true philosophy.
By the spirit of philosophy, he must have been induced to reflect that
such poisoned weapons as he was preparing to use, are hardly ever
allowable in scientific contest, as having a less direct tendency to over-
throw the system, than to hurt the person of an adversary, and to
wound, perhaps incurably, his mind, his reputation, or his peace. By
the maxims of philosophy, he must have been reminded, that, in no part
of the history of nature, has any mark been discovered, either of the
beginning or the end of the present order ; and that the geologist sadly
mistakes, both the object of his science and the limits of his understand-
ing, who thinks it his business to explain the means employed by Infin-
ite Wisdom for establishing the laws which now govern the world.
By attending to these obvious considerations, Mr. Kirwan would
have avoided a very illiberal and ungenerous proceeding ; and, however
he might have differed from Dr. Hutton as to the truth of his opinions,
he would not have censured their tendency with such rash and unjusti-
fiable severity.
But, if this author may be blamed for wanting the temper, or neg-
lecting the rules of philosophic investigation, he is hardly less culpable,
for having so slightingly considered the scope and spirit of a work which
he condemned so freely. In that work, instead of finding the world
represented as the result of necessity or chance, which might be looked
for, if the accusations of atheism or impiety were well founded, we see
everywhere the utmost attention to discover, and the utmost disposi-
tion to admire, the instances of wise and beneficent design manifested in
the structure, or economy of the world. The enlarged views of these,
which his geological system afforded, appeared to Dr. Hutton himself
as its most valuable result. They were the parts of it which he con-
templated with greatest delight ; and he would have been less flattered,
by being told of the ingenuity and originality of his theory, than of the
addition which it had made to our knowledge of final causes. It was
natural, therefore, that he should be hurt by an attempt to accuse him
of opinions, so different from those which he had always taught ; and if
he answered Mr. Kirwan's attack with warmth or asperity, we must
ascribe it to the indignation excited by unmerited reproach.
But to return to the natural history of the earth : Though there be
in it no data, from which the commencement of the present order can
be ascertained, there are many by which the existence of that order may
be traced back to an antiquity extremely remote. The beds of primi-
326 EIGHTEENTH CENTURY SCIENCE
tive schistus, for instance, contain sand, gravel, and other materials,
collected, as already shown, from the dissolution of mineral bodies;
which bodies, therefore, must have existed long before the oldest part
of the land was formed. Again, in this gravel we sometimes find pieces
of sandstone, and of other compound rocks, by which we are of course
carried back a step farther, so as to reach a system of things, from which
the present is the third in succession ; and this may be considered as the
most ancient epoch of which any memorial exists in the records of the
fossil kingdom.
Next in the order of time to the consolidation of the primary strata,
we must place their elevation, when, from being horizontal, and at the
bottom of the sea, they were broken, set on edge, and raised to the sur-
face. It is even probable, as formerly observed, that to this succeeded a
depression of the same strata, and a second elevation, so that they have
twice visited the superior, and twice the inferior regions. During the
second immersion, were formed, first, the great bodies of pudding-stone,
that in so many instances lie immediately above them, and next were
deposited the strata that are strictly denominated secondary.
The third great event was the raising up of this compound body of
old and new strata from the bottom of the sea, and forming it into the
dry land, or the continents, as they now exist. Contemporary with this,
we must suppose the injection of melted matter among the strata, and
the consequent formation of the crystallized and unstratified rocks,
namely, the granite, metallic veins, and veins of porphyry and whin-
stone. This, however, is to be considered as embracing a period of great
duration ; and it must always be recollected, that veins are found of a
very different formation ; so that when we speak generally, it is perhaps
impossible to state anything more precise concerning their antiquity,
than that they are posterior to the strata, and that the veins of whin-
stone seem to be the most recent of all, as they traverse every other.
In the fourth place, with respect to time, we must class the facts
that regard the detritus and waste of the land, and must carefully dis-
tinguish them from the more ancient phenomena of the mineral king-
dom. Here we are to reckon the shaping of all the present inequalities
of the surface ; the formation of hills of gravel, and of what have been
called tertiary strata, consisting of loose and unconsolidated materials ;
also collections of shells not mineralized, like those in Touraine; such
petrifactions as those contained in the rock of Gibraltar, on the coast of
Dalmatia, and in the caves of Bayreuth. The bones of land animals
EIGHTEENTH CENTURY SCIENCE 327
found in the soil, such as those of Siberia, or North America, are prob-
ably more recent than any of the former.
These phenomena, then, are all so many marks of the lapse of time,
among which the principles of geology enable us to distinguish a cer-
tain order, so that we know some of them to be more, and others to be
less distant, but without being able to ascertain, with any exactness, the
proportion of the immense intervals which separate them. These inter-
vals admit of no comparison with the astronomical measures of time,
they cannot be expressed by the revolutions of the sun or of the moon ;
nor is there any synchronism between the most recent epochs of the
mineral kingdom, and the most ancient of our ordinary chronology.
On what is now said is grounded another objection to Dr. Hut-
ton's theory, namely, that the high antiquity ascribed by it to the earth,
is inconsistent with that system of chronology which rests on the author-
tiy of the Sacred Writings. This objection would no doubt be of
weight, if the high antiquity in question were not restricted merely to
the globe of the earth, but were also extended to the human race. That
the origin of mankind does not go back beyond six or seven thousand
years, is a position so involved in the narrative of the Mosaic books, that
anything inconsistent with it would no doubt stand in opposition to the
testimony of those ancient records. On this subject, however, geology
is silent; and the history of arts and sciences, when traced as high as
any authentic monuments extend, refers the beginnings of civilization
to a date not very different from that which has just been mentioned,
and infinitely within the limits of the most recent of the epochs, marked
by the physical revolutions of the globe.
But on the other hand, the authority of the Sacred Books seems to
be but little interested in what regards the mere antiquity of the earth
itself; nor does it appear that their language is to be understood liter-
ally concerning the age of that body, any more than concerning its figure
or its motion. The theory of Dr. Hutton stands here precisely on the
same footing with the system of Copernicus ; for there is no reason to
suppose that it was the purpose of revelation to furnish a standard of
geological, any more than of astronomical science. It is admitted, on all
hands, that the Scriptures are not intended to resolve physical ques-
tions, or to explain matters in no way related to the morality of human
actions ; and if, in consequence of this principle, a considerable latitude
of interpretation were not allowed, we should continue at this moment
to believe that the earth is flat; that the sun moves around the earth;
328 EIGHTEENTH CENTURY SCIENCE
and that the circumference of the circle is no more than three times its
diameter.
It is but reasonable, therefore, that we should extend to the geol-
ogist the same liberty of speculation, which the astronomer and math-
ematician are already in possession of; and this may be done, by
supposing that the chronology of Moses relates only to the human race.
This liberty is not more necessary to Dr. Hutton than to other theorists.
No ingenuity has been able to reconcile the natural history of the globe
with the opinion of its recent origin ; and accordingly the cosmologies of
Kirwan and Deluc, though contrived with more mineralogical skill, are
not less forced and unsatisfactory than those of Burnet and Whiston.
It is impossible to look back on the system which we have thus
endeavoured to illustrate, without being struck with the novelty and
beauty of the views which it sets before us. The very plan and scope of
it distinguish it from all other theories of the earth, and point it out as a
work of great and original invention. The sole object of such theories
has hitherto been, to explain the manner in which the present laws of
the mineral kingdom were first established, or began to exist, without
treating of the manner in which they now proceed, and by which their
continuance is provided for. The authors of these theories have accord-
ingly gone back to a state of things altogether unlike the present, and
have confined their reasonings, or their fictions, to a crisis which has
never existed but once, and which can never return. Dr. Hutton, on the
other hand, has guided his investigation by the philosophical maxim,
Causam naturalem et assiduam quaerimus, non raram et fortuitam. His
theory, accordingly, presents us with a system of wise and provident
economy, where the same instruments are continually employed, and
where the decay and renovation of fossils being carried on at the same
time in the different regions allotted to them, preserve in the earth the
conditions essential for the support of animal and vegetable life. We
have been long accustomed to admire that beautiful contrivance in
nature, by which the water of the ocean, drawn up in vapour by the
atmosphere, imparts, in its descent, fertility to the earth, and becomes
the great cause of vegetation and of life; but now we find, that this
vapour not only fertilizes, but creates the soil; prepares it from the
solid rock, and, after employing it in the great operations of the sur-
face, carries it back into the regions where all its mineral characters are
renewed. Thus, the circulation of moisture through the air, is a prime
mover, not only in the annual succession of the seasons, but in the great
EIGHTEENTH CENTURY SCIENCE 329
geological cycle, by which the waste and reproduction of entire con-
tinents is circumscribed. Perhaps a more striking view than this, of the
wisdom that presides over nature, was never presented by any philo-
sophical system, nor a greater addition ever made to our knowledge of
final causes. It is an addition which gives consistency to the rest, by
proving that equal foresight is exerted in providing for the whole and
for the parts, and that no less care is taken to maintain the constitution
of the earth, than to preserve the tribes of animals and vegetables which
dwell on its surface. In a word, it is the peculiar excellence of this the-
ory, that it ascribes to the phenomena of geology an order similar to
that which exists in the provinces of nature with which we are best
acquainted; that it produces seas and continents, not by accident, but
by the operation of regular and uniform causes ; that it makes the decay
of one part subservient to the restoration of another, and gives stability
to the whole, not by perpetuating individuals, but by reproducing them
in succession.
Again, in the details of this theory, and the ample deduction on
which it is founded, we meet with many facts and observations, either
entirely new, or hitherto very imperfectly understood. Thus, the veins
which produce from masses of granite, and penetrate the incumbent
schistus, had either escaped the observation of former mineralogists, or
the importance of the phenomena had been entirely overlooked. Dr.
Hutton has described the appearances with great accuracy, and drawn
from them the most interesting conclusions. At the junction of the pri-
mary and secondary strata, the facts which he has noted had been
observed by others; but no one, I think, had so fully understood the
language which they speak, or had so clearly perceived the consequences
that necessarily follow from them. He is the first who distinctly pointed
out the characters which distinguish whinstone from lava, and who ex-
plained the true relation that subsists between these substances. He
also discovered the induration of the strata, in contact with veins of
whin, and the charring of the coal in their vicinity. His theory also
enabled him to determine the affinity of whinstone and granite to one
another, and their relation to the other great bodies of the mineral
kingdom.
To the observations of the same excellent geologist we are indebted
for the knowledge of the general and important fact, that all the hard
substances of the mineral kingdom, when elevated into the atmosphere,
have a tendency to decay, and are subject to a disintegration and waste,
- V 6-21
330 EIGHTEENTH CENTURY SCIENCE
to which no limit can be set but that of their entire destruction ; that no
provision is made on the surface for repairing this waste, and that there
no new fossil is produced ; that the formation of all the varied scenery
which the surface of the earth exhibits, depends on the operation of
causes, the momentary exertions of which are familiar to us, though we
knew not before the effects which their accumulated action was able to
produce. These are facts in the natural history of the earth, the discovery
of which is due to Dr. Hutton ; and, should we lay all further specula-
tion aside, and consider the theory of the earth as a work too great to
be attempted by man, we must still regard the phenomena and laws just
mentioned, as forming a solid and valuable addition to our knowledge.
If we would compare this theory with others, as to the invisible
agents which it employs, we must consider, that fire and water are the
two powers which all of them must make use of, so that they can differ
only by the way in which they combine these powers. In Dr. Hutton's
system, water is first employed to deposit and arrange, and then fire to
consolidate, mineralize, and lastly, to elevate the strata; but, with re-
spect to the unstratified or crystallized substances, the action of fire only
is recognised. The system having least affinity to this is the Neptunian,
which ascribes the formation of all minerals to the action of water alone,
and extends this hypothesis even to the unstratified rocks. Here, there-
fore, the action of fire is entirely excluded; and the Neptunists have
certainly made a great sacrifice to the love of truth, or of paradox, in
rejecting the assistance of so powerful an auxiliary.
In the systems which employ the agency of the latter element, we
are to look for a greater resemblance to that of Dr. Hutton, though
many and great marks of distinction are easily perceived. In the cos-
mologies, for example, of Leibnitz and Buffon, fire and water are both
employed, as well as in this ; but they are employed in a reverse order.
These philosophers introduce the action of fire first, and then the action
of water, which is to invert the order of nature altogether, as the con-
solidation of the rocks must be posterior to their stratification. Indeed,
the theory of Buffon is singularly defective : besides inverting the order
of the two great operations of consolidation and stratification, and, of
course, giving no real explanation of the latter, it gives no account of
the elevation, or highly inclined position of the strata ; it makes no dis-
tinction between stratified and unstratified bodies, nor does it offer any
but the most unsatisfactory explanation of the inequalities of the earth's
EIGHTEENTH CENTURY SCIENCE 331
surface. This system, therefore, has but a very distant resemblance to
the Huttonian theory.
The system of Lazzaro Moro has been remarked as approaching
nearer to this theory than any other; and it is certain that one very
important principle is common to them both. The theory of the Italian
geologist was chiefly directed to the explanation of the remains of
marine animals, which are found in mountains far from the sea ; and it
appears to have been suggested to him by the phenomena of the Campi
Phlegraei, and by the production of the new island of Santorini in the
Archipelago. He accordingly supposes that the islands and continents
have been all raised up, like the above mentioned island, from the bot-
tom of the sea, by the force of volcanic fire : that these fires began to
burn under the bottom of the ocean, soon after the creation of the world,
when as yet the ocean covered the whole earth ; that they at first ele-
vated a portion of the land; and in this primitive land no shells are
found, as the original ocean was destitute of fish. The volcanoes con-
tinuing to burn, under the sea, after the creation of animated nature,
the strata that were then raised up by their action were full of shells and
other marine objects ; and, from the violence with which they were ele-
vated, arose the contortions and inclined position which they frequently
possess.
This system is imperfect, as it makes no peculiar provision for the
consolidation of the strata, which, according to it, as well as the Nep-
tunian system, must be ascribed to the action, not of fire, but of water.
No account is given of the mineralization of the shells found in the
strata, or of the difference between them and the shells found loose at
the bottom of the sea ; and no distinction is made between stratified and
unstratified substances. But, with all this, Lazzaro Moro has certainly
the merit of having perceived, that some other power than that which
deposited the strata, must have been employed for their elevation, and
that they have endured the action of a disturbing force.
From this comparison it appears that Dr. Hutton's theory is suf-
ficiently distinct, even from the theories which approach to it most
nearly, to merit, in the strictest sense, the appellation of new and orig-
inal. There are indeed few inventions or discoveries, recorded in the
history of science, to which nearer approaches were not made before they
were fully unfolded. It therefore very well deserves to be distinguished
by a particular name ; and, if it behooves us to follow the analogy ob-
served in the names of the two great systems, which at present divide
332 EIGHTEENTH CENTURY SCIENCE
the opinions of geologists, we may join Mr. Kirwan in calling this the
Plutonic system. For my own part, I would rather have it character-
ized by a less splendid, but juster name, that of the Huttonian theory.
The circumstance, however, which gives to this theory its peculiar
character, and exalts it infinitely above all others, is the introduction of
the principle of pressure, to modify the effects of heat when applied at
the bottom of the sea. This is, in fact, the key to the great enigma of
the mineral kingdom, where, while one set of phenomena indicates the
action of fire, another set, equally remarkable, seem to exclude the pos-
sibility of that action, by presenting us with mineral substances, in such
a state as they could never have been brought into by the operation of
the fires we see at the surface of the earth. These two classes of phe-
nomena are reconciled together, by admitting the power of compression
to confine the volatile parts of bodies when heat is applied to them, in
many instances, to undergo fusion, instead of being calcined or dissi-
pated by burning or inflammation. In this hypothesis, which some affect
to consider as a principle gratuitously assumed, there appears to me
nothing but a very fair and legitimate generalization of the properties of
heat. Combustion and inflammation are chemical processes, to which
other conditions are required, beside the presence of a high tempera-
ture. The state of the mineral regions makes it reasonable to presume,
that these conditions are wanting in the bowels of the earth, where, of
consequence, we have a right to look for nothing but expansion and
fusion, the only operations which seem essential to heat, and insep-
arable from the application of it, in certain degrees to certain substances.
Though this principle, therefore, had no countenance from analogy, the
admirable simplicity, and the unity, which it introduces into the phe-
nomena of geology, would sufficiently justify the application of it to the
theory of the earth.
As another excellence of this theory, I may, perhaps, be allowed to
remark, that it extends its consequences beyond those to which the
author of it has himself adverted, and that it affords, which no geologi-
cal theory has yet done, a satisfactory explanation of the spheroidal
figure of the earth.
Yet, with all these circumstances of originality, grandeur, and sim-
plicity in its favour, with the addition of evidence as demonstrative as
the nature of the subject will admit, this theory has many obstacles to
overcome, before it meets the general approbation. The greatness of
the objects which it sets before us alarms the imagination; the powers
EIGHTEENTH CENTURY SCIENCE 333
which it supposes to be lodged in the subterraneous regions; a heat
which has subdued the most refractory rocks, and lias melted beds of
marble and quartz ; an expansive force which has folded up, or broken
the strata, and raised whole continents from the bottom of the sea ; these
are things with which, however certainly they may be proved, the mind
cannot soon be familiarized. The change and movement also, which
this theory ascribes to all that the senses declare to be most unalterable,
raise up against it the same prejudices which formerly opposed the
belief in the true system of the world ; and it affords a curious proof,
how little such prejudices are subject to vary, that as Aristarchus, an
ancient follower of that system, was charged with impiety for moving
the everlasting Vesta from her place, so Dr. Hutton, nearly on the same
ground, has been subjected to the very same accusation. Even the length
of time which this theory regards as necessary to the revolutions of the
globe, is looked on as belonging to the marvelous ; and man, who finds
himself constrained by the want of time, or of space, in almost all his
undertakings, forgets, that in these, if in anything, the riches of nature
reject all limitations.
The evidence which must be opposed to all these causes of incredul-
ity, cannot be fully understood without much study and attention. It
requires not only a careful examination of particular instances, but com-
prehensive views of the whole phenomena of geology ; the comparison of
things very remote with one another ; the interpretation of the obscure
by the luminous, and of the doubtful by the decisive appearances. The
geologist must not content himself with examining the insulated speci-
mens of his cabinet, or with pursuing the nice subtleties of mineralogical
arrangement; he must study the relation of fossils, as they actually
exist; he must follow nature into her wildest and most inaccessible
abodes ; he must select, for the places of his observations, those points
from which the variety and gradation of her works can be most exten-
sively and accurately explored. Without such an exact and compre-
hensive survey, his mind will hardly be prepared to relish the true the-
ory of the earth. "Naturae enlm vis atque majestas omnibus momcntis
fide caret, si quis modo partes atque non, totam complectatur animo."
If indeed this theory of the earth is, as we suppose it to be, the
lapse of time must necessarily remove all objections to it, and the prog-
ress of science will only develop its evidence more fully. As it stands
at present, though true, it must be still imperfect; and it cannot be
doubted, that the great principles of it, though established on an immov-
334 EIGHTEENTH CENTURY SCIENCE
able basis, must yet undergo many modifications, requiring to be lim-
ited, in one place, or to be extended, in another. A work of such variety
and extent cannot be carried to perfection by the efforts of an individual.
Ages may be required to fill up the bold outline which Dr. Hutton has
traced with so masterly a hand; to detach the parts more completely
from the general mass ; to adjust the size and position of the subordin-
ate members ; and to give to the whole piece the exact proportion and
true colouring of nature.
This, however, in length of time, may be expected from the ad-
vancement of science, and from the mutual assistance which parts of
Knowledge, seemingly most remote, often afford to one another. Not
only may the observations of the mineralogist, in tracts yet unexplored,
complete the enumeration of geological facts; and the experiments of
the chemist, on subjects not yet subjected to his analysis, afford a more
intimate acquaintance with the nature of fossils, and a measure of the
power of those chemical agents to which this theory ascribes such vast
effects; but also from other sciences, less directly connected with the
natural history of the earth, much information may be received. The
accurate geographical maps and surveys which are now making; the
soundings ; the observation of the currents ; the barometrical measure-
ments, may all combine to ascertain the reality, and to fix the quantity
of those changes which terrestrial bodies continually undergo. Every
new improvement in science affords the means of delineating more accu-
rately the face of nature as it now exists, and of transmitting, to future
ages, an account, which may be compared with the face of nature as it
shall then exist. If, therefore, the science of the present times is des-
tined to survive the physical revolutions of the globe, the Huttonian
Theory may be confirmed by historical record; and the author of it
will be remembered among the illustrious few, whose systems have been
verified by the observations of succeeding ages, supported by facts un-
known to themselves, and established by the decisions of a tribunal,
slow, but infallible, in distinguishing between truth and falsehood.
335
HERSCHEL
SIR WILLIAM HERSCHEL was born in Hanover, Germany, November
15, 1738. He was the son of a bandmaster and was specially educated
in music. At fourteen he was forced to earn his own living and joined
the band of the Hanoverian Guards. This took him to England in 1759.
He later became organist at Bath. All this time he studied the lan-
guages and mathematics by himself. He grew to be much interested in
the science of music and was led from this to take interest in the fabled
"music of the spheres."
Even an ordinary telescope was beyond his means, and he at length,
after some 200 failures, succeeded in constructing specula for a tele-
scope that he considered satisfactory. In 1781 with one of his own tele-
scopes he discovered the planet Uranus, thought at first to be a comet.
Honors now fell fast upon him. He discovered two of the satellites of
Uranus, two more of Saturn, and that the moon is without atmosphere ;
noted many of the binary stars ; made the great inference from the
movements of the stars that the whole solar system is rushing toward
the constellation of Hercules ; and pointed out many nebulous stars,
which led directly to the nebular theory of the universe.
He died in 1822. His one son, Sir John Herschel, became also a
famous astronomer.
THE DISCOVERY OF URANUS
ACCOUNT OF A COMET
On Tuesday, the i3th of March, 1781, between 10 and n in the
evening, while examining the small stars in the neighborhood of H
Geminorum, I perceived one that appeared visibly larger than the rest :
being struck with its uncommon magnitude, I compared it to H Gemin-
orum and the small star in the quartile between Auriga and Gemini,
and finding it so much larger than either of them, suspected it to be a
comet. I was then engaged in a series of observations on the parallax
336 EIGHTEENTH CENTURY SCIENCE
of the fixed stars, which I hope soon to have the honour of laying before
the R. S. ; and those observations requiring very high powers, I had
ready at hand several magnifiers of 227, 460, 932, 1536, 2010, &c., all of
which I have successfully used on that occasion. The power I had on
when I first saw the comet was 227. From experience I knew that the
diameters of the fixed stars are not proportionally magnified with
higher powers, as the planets are ; I therefore now put on the powers of
460 and 932, and found the diameter of the comet increased in propor-
tion to the power, as it ought to be, on a supposition of its not being a
fixed star, while the diameters of the stars to which I compared it,
were not increased in the same ratio. Also, that the comet being magni-
fied much beyond what its light would admit of, appeared hazy and ill-
defined with these great powers, while the stars preserved that lustre
and distinctness which from many thousand observations I knew they
would retain. The sequel has shown that my surmises were well
founded, this proving to be the comet we have lately observed.
Mr. H. reduced all his observations on this comet to three tables.
The first contains the measures of the gradual increase of the comet's
diameter. The micrometers he used, when every circumstance is favour-
able will measure extremely small angles, such as do not exceed a few
seconds, true to 6, 8, or 10 thirds at most ; and in the worst situations
true to 20 or 30 thirds ; he therefore gave the measures of the comet's
diameter in seconds and thirds. The first table, containing the meas-
ures of the comet's diameter, shows that, from March 17 to April 18,
the apparent diameter had increased from 2" 53"' to 5' 20"'.
The second table contains the comet's distances from several tele-
scopic fixed stars from March 13 till April 19, and those distances ex-
pressed in minutes, seconds and thirds. And the third table contains the
comet's angle of position with regard to the parallel of declination of the
same stars measured by a micrometer; by which means its places and
apparent path might be determined. — Trans. Roy. Phil. Soc.
ON THE NAME OF THE NEW PLANET
By the observations of the most eminent astronomers in Europe it
appears that the new star, which I had the honour of pointing out to
them in March, 1781, is a primary planet of our solar system.* A body
* The observations of this new planet, at first suspected to be a comet, are abridged at p. 154,
of this volume. Dr. Herschel, the discoverer, here calls it the Georgium Sidus, or Georgian
planet, in honour of his Majesty; by which name it is commonly distinguished in this country.
EIGHTEENTH CENTURY SCIENCE 337
so nearly related to us by its similar condition and situation, in the
unbounded expanse of the starry heavens, must often be the subject of
conversation, not only of astronomers, but of every lover of science in
general. This consideration, then, makes it necessary to give it a name,
by which it may be distinguished from the rest of the planets and fixed
stars. In the fabulous ages of ancient times the appellations of Mer-
cury, Venus, Mars, Jupiter, and Saturn, were given to the planets, as
being the names of their principal heroes and divinities. In the present
more philosophical era, it would hardly be allowable to have recourse to
the same method, and call on Juno, Apollo, Pallas or Minerva, for a
name to our new heavenly body. The first consideration in any partic-
ular event, or remarkable incident, seems to be its chronology ; if in any
future age it should be asked, when this last-found planet was discov-
ered it would be a very satisfactory answer to say, "In the reign of
King George the Third." As a philosopher, then, the name of Geor-
gium Sidus presents itself to me, as an appellation which will conven-
iently convey the information of the time and country where and when
it was brought to view.
ON NEBULOUS STARS, PROPERLY SO CALLED
In one of his late examinations of a space in the heavens, which he
had not reviewed before, Dr. H. discovered a star of about the eighth
magnitude, surrounded with a faintly luminous atmosphere, of a con-
siderable extent. The phenomenon was so striking that he could not
help reflecting on the circumstance that attended it, which appeared to
be of a very instructive nature, and such as might lead to inferences
which will throw a considerable light on some points relating to the con-
struction of the heavens.
Cloudy or nebulous stars have been mentioned by several astron-
omers; but this name ought not to be applied to the objects which they
have pointed out as such ; for, on examination, they proved to be either
mere clusters of stars, plainly to be distinguished with his large instru-
But, in other countries it is often called by other names; as Ouranus, Uranius, Herschel, &c.
Its Astronomical mark, or character is H . By later observations and calculations it has been
determined that the diameter of this planet is about 35,109 miles, or 4 4-10 times that of the earth;
its distance from the sun 1800 millions of miles, or above 19 times the earth's distance; that the
period of its revolution in its orbit round the sun, is 83 years. 140 days, 17 hours, Dr. Herschel
has also discovered 6 satellites or moons belonging to this planet, whose orbits are nearly per-
pendicular to the plane of the ecliptic; and they all perform their revolutions in their orbits
contrary to the order of the signs, that is, their real motion is retrograde.— Original note.
338 EIGHTEENTH CENTURY SCIENCE
ments, or such nebulous appearances as might be reasonably supposed
to be occasioned by a multitude of stars at a vast distance. The milky
way itself consists entirely of stars, and by imperceptible degrees he was
led on from most evident congeries of stars to other groups in which the
lucid points were smaller, but still very plainly to be seen; and from
them to such wherein they could but barely be suspected, till he arrived
at last to spots in which no trace of a star was to be discerned. But then
the gradations to these later were by such well-connected steps as left
no room for doubt but that all these phenomena were equally occasioned
by stars, variously dispersed in the immense expanse of the universe.
When Dr. H. pursued these researches, he was in the situation of a
natural philosopher who follows the various species of animals and in-
sects from the height of their perfection down to the lowest ebb of life ;
when, arriving at the vegetable kingdom, he can scarcely point out to us
the precise boundary where the animal ceases and the plant begins ; and
may even go so far as to suspect them not to be essentially different.
But recollecting himself, he compares, for instance, one of the human
species to a tree, and all doubt of the subject vanishes before him. In
the same manner we pass through gentle steps from a coarse cluster of
stars, such as the Pleiades, the Prseserpe, the milky way, the cluster in
the Crab, the nebula in Hercules, that near the preceding hip of Bootis,
the I7th, 38th, 41 st of the 7th class of his catalogues, the loth, 2Oth,
35th of the 6th class, the 33d, 48th, 21 3th of the ist, the I2th, I5oth,
756th of the 2d, and the i8th, i4Oth, 725th of the 3d, without any hesi-
tation, till we find ourselves brought to an object such as the nebula in
Orion, where we are still inclined to remain in the once adopted idea, of
stars exceedingly remote, and inconceivably crowded, as being the occa-
sion of that remarkable appearance. It seems, therefore, to require a
more dissimilar object to set us right again. A glance like that of the
naturalist, who casts his eye from the perfect animal to the perfect vege-
table, is wanting to remove the veil from the mind of the astronomer.
The object mentioned above is the phenomenon that was wanting for
this purpose. View, for instance, the igth cluster of the 6th class, and
afterwards cast your eye on this cloudy star, and the result will be no
less decisive than that of the naturalist alluded to. Our judgment will
be, that the nebulosity about the star is not of a starry nature.
But that we may not be too precipitate in these new decisions,
let us enter more at large into the various grounds which induced us
EIGHTEENTH CENTURY SCIENCE 339
formerly to surmise, that every visible object, in the extended and dis-
tant heavens, was of the starry kind, and collate them with those which
now offer themselves for the contrary opinion. It has been observed, on
a former occasion, that all the smaller parts of other great systems, such
as the planets, their rings and satellites, the comets, and such other
bodies of the like nature as may belong to them, can never be perceived
by us, on account of the faintness of light reflected from small opaque
objects : in the present remarks, therefore, all these are to be entirely set
aside.
A well connected series of objects, such as mentioned above, has
led us to infer that all nebulae consist of stars. This being admitted, we
were authorized to extend our analogical way of reasoning a little fur-
ther. Many of the nebulae had no other appearance than that whitish
cloudiness, on the blue ground on which they seemed to be projected;
and why the same cause should not be assigned to explain the most ex-
tensive nebulosities, as well as those that amounted only to a few min-
utes of a degree in size, did not appear. It could not be inconsistent to
call up a telescopic milky way, at an immense distance, to account for
such a phenomenon ; and if any part of the nebulosity seemed detached
from the rest, or contained a visible star or two, the probability of see-
ing a few near stars, apparently scattered over the far distant regions of
myriads of sidereal collections, rendered nebulous by their distance,
would also clear up these singularities.
In order to be more easily understood in his remarks on the com-
parative disposition of the heavenly bodies, Dr. H. mentions some of the
particulars which introduced the ideas of connection and disjunction:
for these, being properly founded on an examination of objects that
may be reviewed at any time, will be of considerable importance to the
validity of what we may advance with regard to the lately discovered
nebulous stars. On June 27, 1786, he saw a beautiful cluster of very
small stars of various sizes, about 15' in diameter, and very rich of stars.
On viewing this object, it is impossible to withhold our assent to the
idea which occurs, that these stars are connected so far with one another
as to be gathered together, within a certain space, of little extent when
compared to the vast expanse of the heavens. As this phenomenon has
been repeatedly seen in a thousand cases, Dr. H. thinks he may justly
lay great stress on the idea of such stars being connected. On Septem-
ber 9, 1779, he discovered a very small star near e Bootis. The question
here occurring, whether it had any connection with e or not, was deter-
340 EIGHTEENTH CENTURY SCIENCE
mined in the negative ; for, considering the number of stars scattered in
a variety of places, it is very far from being uncommon, that a star at a
great distance should happen to be nearly in a line drawn from the sun
through e, and thus constitute the observed double star. September 7,
1782, when Dr. H. first saw the planetary nebula near v Aquarii, he pro-
nounced it to be a system whose parts were connected together. With-
out entering into any kind of calculation, it is evident, that a certain
degree of light within a very small space, joined to the particular shape
this object presents to us, which is nearly round, and even in its devia-
tion consistent with regularity, being a little elliptical, ought naturally
to give us the idea of a conjunction in the things that produce it. And
a considerable addition to this argument may be derived from a repeti-
tion of the same phenomenon, in nine or ten more of a similar construc-
tion.
When Dr. H. examined the cluster of stars, following the head of
the Great Dog, he found on March 19, 1786, that there was within this
cluster a round, resolvable nebula, of about 2' in diameter, and nearly
an equal degree of light throughout. Here, considering that the cluster
was free from nebulosity in other parts, and that many such clusters, as
well as such nebulae, exist in divers parts of the heavens, it seemed very
probable that the nebula was unconnected with the cluster; and that a
similar reason would as easily account for this appearance as it had
resolved the phenomenon of the double star near e Bootis; that is, a
casual situation of our sun and the two othe$ objects nearly in a line.
And though it may be rather more remarkable, that this should happen
with two compound systems, which are not by far so numerous as sin-
gle stars, we have, to make up for this singularity, a much larger space
in which it may take place, the cluster being of a very considerable
extent.
On February 15, 1786, Dr. H. discovered that one of his planetary
nebulae had a spot in the centre, which was more luminous than the rest,
and with long attention, a very bright, round, well-defined centre became
visible. He remained not a single moment in doubt, but that the bright
centre was connected with the rest of the apparent disc. October 6,
1785, he found a very bright, round nebula, of about i£' in diameter. It
has a large, bright nucleus in the middle, which is undoubtedly con-
nected with the luminous parts about it. And though we must confess,
that if this phenomenon, and many more of the same nature, recorded in
the catalogues of nebulae, consist of clustering stars, we find ourselves
EIGHTEENTH CENTURY SCIENCE 341
involved in some difficulty to account for the extraordinary condensation
of them about the centre ; yet the idea of a connection between the out-
ward parts and these very condensed ones within, is by no means less-
ened on that account.
There is a telescopic milky way, which Dr. H. has traced out in the
heavens in many sweeps made from the year 1783 to 1789. It takes up
a space of more than 60 square degrees of the heavens, and there are
thousands of stars scattered over it : among others, four that form a tra-
pezium, and are situated in the well known nebula of Orion, which is
included in the above extent. All these stars, as well as the four men-
tioned, he takes to be entirely unconnected with the nebulosity which
involves them in appearance. Among them is also d Orionis, a cloudy
star, improperly so called by former astronomers ; but it does not seem
to be connected with the milkiness any more than the rest.
Dr. H. now comes to some other phenomena, that, from their sin-
gularity, merit undoubtedly a very full discussion. Among the reasons
which induced us to embrace the opinion, that all very faint milky nebu-
losity ought to be ascribed to an assemblage of stars is, that we could not
easily assign any other cause of sufficient importance for such luminous
appearances, to reach us at the immense distance we must suppose our-
selves to be from them. But if an argument of considerable force should
now be brought forward, to show the existence of luminous matter, in a
state of modification very different from the construction of a sun or
star, all objections, drawn from our incapacity of accounting for new
phenomena on old principles, he thinks, will lose their validity.
Hitherto Dr. H. has been showing, by various instances in objects
whose places are given, in what manner we may form ideas of connec-
tion, and its contrary, by an attentive inspection of them only ; he now
relates a series of observations, with remarks on them as they are deliv-
ered, from which he afterwards draws a few simple conclusions, that
seem to be of considerable importance.
October 16, 1784. A star of about the ninth magnitude, surrounded
by a milky nebulosity, or chevelure, of about 3' in diameter. The nebu-
losity is very faint, and a little extended or elliptical, the extent being
not far from the meridian, or a little from north preceding to south fol-
lowing. The chevelure involves a small star, which is about i^' north
of the cloudy star; other stars of equal magnitude are perfectly free
from this appearance. (R. A. 5h 57m 45. P. 0.96° 22'). His present
judgment concerning this remarkable object is, that the nebulosity
342 EIGHTEENTH CENTURY SCIENCE
belongs to the star which is situated in its centre. The small one, on
the contrary, which is mentioned as involved, being one of many that
are profusely scattered over this rich neighbourhood, he supposes to be
quite unconnected with this phenomenon. A circle of 3' in diameter is
sufficiently large to admit another small star, without any bias to the
judgment he formed concerning the one in question. It must appear
singular, that such an object should not have immediately suggested all
the remarks contained in this paper ; but about things that appear new
we ought not to form opinions too hastily, and his observations on the
construction of the heavens were then but entered on. In this case,
therefore, it was the safest way to lay down a rule not to reason on the
phenomena that might offer themselves, till he should be in possession of
a sufficient stock of materials to guide his researches.
October 16, 1784. A small star of about the nth or I2th magnitude,
very faintly affected with milky nebulosity ; other stars of the same mag-
nitude were perfectly free from this appearance. Another observation
mentions five or six small stars within the space of 3 or 4', all very
faintly affected in the same manner, and the nebulosity suspected to be a
little stronger about each star. But a third observation rather opposes
this increase of the faintly luminous appearance. (R. A. 6h om 335.
P. D. 96° 13'). Here the connection between the stars and the nebu-
losity is not so evident as to amount to conviction ; for which reason we
shall pass on to the next.
* * *
November 25, 1788. A star of about the pth magnitude, sur-
rounded with very faint milky nebulosity ; other stars of the same size
are perfectly free from that appearance. Less than i' in diameter. The
star is either not round or double (a).
March 23, 1789. A bright, considerably well-defined nucleus, with
a very faint, small, round chevelure (b). The connection admits of no
doubt ; but the object is not perhaps of the same nature with those called
cloudy stars.
April 14, 1789. A considerable, bright, round nebula; having a
large place in the middle of nearly an equal brightness ; but less bright
towards the margin (c). This seems rather to approach the planetary
sort.
March 5, 1790. A pretty considerable star of the gth or loth mag-
nitude, visibly affected with a very faint nebulosity of little extent, all
EIGHTEENTH CENTURY SCIENCE 343
around. A power of 300 showed the nebulosity of greater extent (d).
The connection is not to be doubted.
March 19, 1790. A very bright nucleus, with a small, very faint
chevelure, exactly round. In a low situation, where the chevelure could
hardly be seen, this object would put on the appearance of an ill-defined,
planetary nebula, of 6, 8 or 10" diameter (e).
November 13, 1790. A most singular phenomenon! A star of
about the 8th magnitude, with a faint luminous atmosphere, of a circu-
lar form, and of about 3' in diameter. The star is perfectly in the centre,
and the atmosphere is so diluted, faint, and equal throughout, that there
can be no surmise of its consisting of stars ; nor can there be a doubt of
the evident connection between the atmosphere and the star. Another
star not much less in brightness, and in the same field with the above,
was perfectly free from any such appearance. This last object is so
decisive in every particular, Dr. H. says, that we need not hesitate to
admit it as a pattern, from which we are authorised to draw the follow-
ing important consequences :
Supposing the connection between the star and its surrounding nebu-
losity to be allowed, we argue, that one of the two following cases must
necessarily be admitted : In the first place, if the nebulosity consist of
stars that are very remote, which appear nebulous on account of the
small angles their mutual distances subtend at the eye, by which they
will not only, as it were, run into each other, but also appear extremely
faint and diluted; then, what must be the enormous size of the central
point, which outshines all the rest in so superlative a degree as to admit
of no comparison ! In the next place, if the star be no larger than com-
mon, how very small and compressed must be those other luminous
points that are the occasion of the nebulosity which surrounds the cen-
tral one! As, by the former supposition, the luminous central point
must far exceed the standard of what we call a star, so, in the latter, the
shining matter about the centre will be much too small to come under
the same denomination ; we therefore either have a central body which
is not a star, or have a star which is involved in a shining fluid, of a
nature totally unknown to us. Dr. H. can adopt no other sentiment than
the latter, since the probability is certainly not for the existence of so
enormous a body as would be required to shine like a star of the eighth
magnitude, at a distance sufficiently great to cause a vast system of stars
to put on the appearance of a very diluted milky nebulosity.
But what a field of novelty is here opened to our conceptions ! A
344 EIGHTEENTH CENTURY SCIENCE
shining fluid, of a brightness sufficient to reach us from the remote
regions of a star of the 8th, 9th, loth, or I2th magnitude, and of an
extent so considerable as to take up 3, 4, 5, or 6 minutes in diameter !
Can we compare it to the coruscation of the electric fluid in the aurora
borealis ? Or to the more magnificent cone of the zodiacal light as we
see it in the spring or autumn ? The latter, notwithstanding Dr. H. has
observed it to reach at least 90° from the sun, is yet of so little extent
and brightness, as probably not to be perceived even by the inhabitants
of Saturn or the Georgian planet, and must be utterly invisible at the
remoteness of the nearest fixed star.
More extensive views may be derived from this proof of the exist-
ence of a shining matter. Perhaps it has been too hastily surmised that
all milky nebulosity, of which there is so much in the heavens, is owing
to starlight only. These nebulous stars may serve as a clue to unravel
other mysterious phenomena. If the shining fluid that surrounds them
is not so essentially connected with these nebulous stars, but that it can
also exist without them, which seems to be sufficiently probable, and will
be examined hereafter, we may with great facility explain that very
extensive, telescopic nebulosity, which, as before mentioned, is expanded
over more than 60° of the heavens, about the constellation of Orion ; a
luminous matter accounting much better for it than clustering stars at a
distance. In this case we may also pretty nearly guess at its situation,
which must commence somewhere about the range of the stars of the
7th magnitude, or a little farther from us, and extend unequally in some
places perhaps to the regions of those of the gth, loth, nth, and I2th.
The foundation for this surmise is, that not unlikely some of the stars
that happen to be situated in a more condensed part of it, or that per-
haps by their own attraction draw together some quantity of this fluid
greater than what they are entitled to by their situation in it, will, of
course, assume the appearance of cloudy stars; and many of those
named are either in this stratum of luminous matter, or very near it.
It has been said above, that in nebulous stars the existence of the
shining fluid does not seem to be so essentially connected with the cen-
tral points that it might not also exist without them. For this opinion
we may assign several reasons. One of them is the greater resemblance
of the chevelure of these stars and the diffused extensive nebulosity
mentioned before, which renders it highly probable that they are of the
same nature. Now, if this be admitted, the separate existence of the
luminous matter, or its independence of a central star, is fully proved.
EIGHTEENTH CENTURY SCIENCE 345
We may also judge, very confidently, that the light of this shining fluid
is no kind of reflection from the star in the centre; for, as we have
already observed, reflected light could never reach us at the great dis-
tance we are from such objects. Besides, how impenetrable would be
an atmosphere of a sufficient density to reflect so great a quantity of
light! And yet we observe, that the outward parts of the chevelure
are nearly as bright as those that are close to the star ; so that this sup-
posed atmosphere ought to give no obstruction to the passage of the
central rays. If therefore this matter is self-luminous, it seems more
fit to produce a star by its condensation than to depend on the star for
its existence.
Many other diffused nebulosities, besides that about the constella-
tion of Orion, have been observed or suspected ; but some of them are
probably very distant, and run far out into space. For instance, about
5m in time preceding x Cygni, Dr. H. suspects as much of it as covers
near 4 square degrees ; and much about the same quantity 44m preced-
ing the 125 Tauri. A space of almost 8 square degrees, 6m preceding
a Trianguli, seems to be tinged with milky nebulosity. Three minutes
preceding the 46 Eridani, strong, milky nebulosity is expanded over
more than 2 square degrees. Fifty-four minutes preceding the I3th
Canum venaticorum, and again 48111 preceding the same star, the field of
view affected with whitish nebulosity throughout the whole breadth of
the sweep, which was 2° 39'. Four minutes following the 57 Cygni a con-
siderable space is filled with faint, milky nebulosity, which is pretty
bright in some places, and contains the 37th nebula of the 5th class, in
the brightest part of it. In the neighbourhood of the 44th Piscium, very
faint nebulosity appears to be diffused over more than 9 square degrees
of the heavens. Now all these phenomena, as we have already seen,
will admit of a much easier explanation by a luminous fluid than by stars
at an immense distance.
The nature of planetary nebulas, which has hitherto been involved
in much darkness, may now be explained with some degree of satisfac-
tion, since the uniform and very considerable brightness of their appar-
ent disc accords remarkably well with a much condensed, luminous
fluid ; whereas, to suppose them to consist of clustering stars, will not so
completely account for the milkiness or soft tint of their light, to pro-
duce which it would be required that the condensation of the stars
should be carried to an almost inconceivable degree of accumulation.
The surmise of the regeneration of stars, by means of planetary nebulae,
V 6-22
346 EIGHTEENTH CENTURY SCIENCE
expressed in a former paper, will become more probable, as all the
luminous matter contained in one of them, when gathered together into
a body of the size of a star, would have nearly such a quantity of light as
we find the planetary nebulae to give. To prove this experimentally, we
may view them with a telescope that does not magnify sufficiently to
show their extent, by which means we shall gather all their light together
into a point, when they will be found to assume the appearance of small
stars ; that is, of stars at the distance of those which we call of the 8th,
9th, or loth magnitude. Indeed this idea is greatly supported by the dis-
covery of a well-defined, lucid point, resembling a star, in the centre of
one of them ; for the argument which has been used, in the case of nebu-
lous stars, to show the probability of the existence of luminous matter,
which rested on the disparity between a bright point and its surround-
ing shining fluid, may here be alleged with equal justice. If the point
be a generating star, the further accumulation of the already much con-
densed, luminous matter may complete it in time.
How far the light that is perpetually emitted from millions of suns
may be concerned in this shining fluid, it might be presumptious to
attempt to determine; but, notwithstanding the inconceivable subtilty
of the particles of light, when the number of the emitting bodies is
almost infinitely great, and the time of the continual emission indefin-
itely long, the quantity of emitted particles may well become adequate to
the constitution of a shining fluid, or luminous matter, provided a cause
can be found that may retain them from flying off, or reunite them. But
such a cause cannot be difficult to guess at, when we know that light is
so easily reflected, refracted, inflected and deflected; and that, in the
immense range of its course, it must pass through innumerable systems,
where it cannot but frequently meet with many obstacles to its rectilinear
progression. Not to mention the great counteraction of the united at-
tractive force of whole sidereal systems, which must be continually ex-
erting their power on the particles while they are endeavouring to fly off.
However, we shall lay no stress on a surmise of this kind, as the means
of verifying it are wanting ; nor is it of any immediate consequence to us
to know the origin of the luminous matter. Let it suffice, that its exist-
ence is rendered evident, by means of nebulous stars. — The Report by
Herschel in the Trans, of the Royal Phil. Soc. of London.
EIGHTEENTH CENTURY SCIENCE 347
ON THE PROPER MOTION OF THE SUN AND SOLAR
SYSTEM
That several of the fixed stars have a proper motion, is now already
so well confirmed that it will admit of no further doubt. From the time
this was first suspected by Dr. Halley we have had continued observa-
tions that show Arcturus, Sirius, Aldebaran, Procyon, Castor, Rigel,
Altair, and many more, to be actually in motion; and considering the
shortness of the time we have had observations accurate enough for the
purpose, it may rather be wondered that we have already been able to
find the motions of so many, than that we have not discovered like altera-
tions in all the rest. Besides, we are well prepared to find numbers of
them apparently at rest, as, on account of their immense distance, a
change of place cannot be expected to become visible to us till after many
ages of careful attention and close observation, though every one of them
should have a motion of the same importance with Arcturus. This con-
sideration alone would lead us strongly to suspect, that there is not,
strictly speaking, one fixed star in the heavens ; but many other reasons
will render this so obvious, that there can hardly remain a doubt of the
general motion of all the starry systems, and consequently of the solar
one among the rest.
We might begin with principles drawn from the theory of attrac-
tion, which evidently oppose every idea of absolute rest in any one of the
stars, when once it is known that some of them are in motion ; for the
change that must arise by such motion, in the value of a power which
acts inversely as the squares of the distances, must be felt in all the
neighbouring stars ; and if these be influenced by the motion of the for-
mer, they will again affect those that are next to them, and so on until
all are in motion. Now as we know that several stars, in divers parts
of the heavens, do actually change their places, it will follow, that the
motion of our solar systems is not a mere hypothesis ; and what will give
additional weight to this consideration is, that we have the greatest rea-
son to suppose most of those very stars, which have been observed to
move, to be such as are nearest to us ; and therefore their influence on
our situation would alone prove a powerful argument in favour of the
proper motion of the sun, had it been originally at rest.
Admitting this for granted, the greatest difficulty will be, how to
348 EIGHTEENTH CENTURY SCIENCE
discern the proper motion of the sun among so many other, and vari-
ously compounded, motions of the stars. This is an arduous task indeed,
which we must not hope to see accomplished in our time ; but we are not
to be discouraged from the attempt. Let us, at all events, says Mr. H.,
endeavour to lay a good foundation for those who are to come after us.
I shall therefore now point out the method of detecting the direction and
quantity of the supposed proper motion of the sun by a few geometrical
deductions, and at the same time show by an application of them to some
known facts, that we have already some reasons to guess which way the
solar system is probably tending in its course.
It remains now only to make an application of this theory to some
of the facts we are already acquainted with, relating to the proper mo-
tion of the stars. Astronomers have already observed what they call a
proper motion in several of the fixed stars, and the same may be sup-
posed of them all. We ought therefore to resolve that which is com-
mon to all the stars, which are found to have what has been called a
proper motion, into a single real motion of the solar system, as far as
that will answer the known facts; and only to attribute the proper
motion of each particular star, the deviations from the general law the
stars seem to follow in those movements. By Dr. Maskelyne's account
of the proper motion of some principal stars, we find that Sirius, Cas-
tor, Procyon, Pollux, Regulus, Arcturus, and a Aquilse, appear to have
respectively the following proper motions in right ascension: -o".6^;
-o".28 ; -o".8o ; -o".93 ; o"4i ; -i"4O+o".57 ; and two of them, Sirius and
Arcturus, in declination, viz. i".2O and 2".oi, both southward. Let figure
10 represent an equatorial zone, with the above mentioned stars referred
to it, according to their respective right ascensions, having the solar sys-
tem in its centre. Assume the direction ab from a point somewhere not
far from the 77th degree of right ascension to its opposite 257th degree,
and suppose the sun to move in that direction from s towards b ; then
will that one motion answer that of all the stars together : for if the sup-
position be true, Arcturus, Regulus, Pollux, Procyon, Castor and Sirius,
should appear to increase. Again, suppose the sun to ascend at the same
time in the same direction towards some point in the northern hemi-
sphere, for instance, towards the constellation of Hercules; then will
also the observed change of declination of Sirius and Arcturus be re-
solved into the single motion of the solar system. But lest Mr. H. should
be censured for admitting so new and capital a motion on too slight a
foundation, he observes, that the concurrence of those seven principal
BH SCIENCE
»ter ' .. • • - .= :«'. - u •- '1-r >YI!! >:mplify th*
is m gi'iv.';,,' \l r- V-H.-V: 'H»t vh*1 ?<-« At thr distance of
f<; Mar, would appear hkt oot of tht«* »v f -•« ..,;.' ^ v wo con-
ihe stars to be suns. Now, **K;
:«cven stars may be accounted for. rj
"in the manner they appear to do, or <ls
have a motion in a direction, somehow not t tr trot
to it, We are no more authorized to suppose ihe sun .^r i ,
deny the diurnal motion of the earth, except in this r-. ;
proof* of the latter are very numerous, whereas the former rt.-.H* ji.h
a i iCbtimonies.
33AJSAJ
• • •
raont, and s<
ter to him on the principles of math-:-:
he was busy with I^agrange in establishing the perr^.nenc- 'ht» sofar
system, accounting for its perturbations, and interactions, and st;<n\ing
that all these chan^--* are pt-nodic. Hi:- ''.Mechanics of the Hu'iver,--'
was a gigantic exposition ui tin f;<.'Vi-»f»«-ntr of tin- •x»ar ft v Mem. Iti iiis
' - -.s«*^> ;.f th* World ' IT,' advanced the r.<l»f?; ,- h»Tx'ihe55« <»f rh-- origin
••xv-^r1!'.'. Mc»Nt of Vus previot^ woi k 'i.i-; Vm dune in rrac-ir^:
ts-'- «•--.« \ :?*t ton thf<sujfhou< *,t8 n»:»n\' compiications, in tii* «.v%»^:i
•'.^ '-(:?-< ! ',!>• '\<r'" , <«.'frt:st-'*() U'> ,1 n'l"/ »t •?!« .ii>!
o< tvv- •? th< vVmrju ; ^^-M -.-.-. -j^.t't
tlwu- >»u*i!*fe
lie it.-.- •• a r-''iiJCfcM» His
ability ro «:i-<> • .-. .;!i t^c- «-*• >i count
from Napoi<x>i\ *tr.'.i of marfjui* • ,.:rL<m kuig.
He died March 5, 1827.
LAPLACE
ngraving from an original picture by Nedeon
EIGHTEENTH CENTURY SCIENCE 349
stars cannot but give some value to an hypothesis that will simplify the
celestial motions in general. We know that the sun, at the distance of
the fixed star, would appear like one of them ; and from analogy we con-
clude the stars to be suns. Now, since the apparent motions of these
seven stars may be accounted for, either by supposing them to move just
in the manner they appear to do, or else by supposing the sun alone to
have a motion in a direction, somehow not far from that above assigned
to it, we are no more authorized to suppose the sun at rest, than we are to
deny the diurnal motion of the earth, except in this respect, that the
proofs of the latter are very numerous, whereas the former rests only on
a few though capital testimonies.
LAPLACE
PIERRE SIMON LAPLACE was born in Normandy, March 28, 1749.
Before eighteen years old he was a teacher of mathematics at Beau-
mont, and soon afterwards gained the attention of D'Alembert by a let-
ter to him on the principles of mathematics. From 1770 for many years
he was busy with Lagrange in establishing the permanency of the solar
system, accounting for its perturbations, and interactions, and showing
that all these changes are periodic. His "Mechanics of the Heavens"
was a gigantic exposition of the movements of the solar system. In his
"System of the World" he advanced the nebular hypothesis of the origin
of the universe. Most of his previous work had been done in tracing
the law of gravitation throughout its many complications, in the system
of planets : this latter hypothesis, though relegated to a note at the end
of the "System of the World," was to give astronomy a dynamic rather
than a descriptive point of view.
He tried to be a politician, but was not a good man of affairs. His
ability to change with the wind, however, brought him a title of count
from Napoleon, and of marquis ( 1817) from the restored Bourbon king.
He died March 5, 1827.
350 EIGHTEENTH CENTURY SCIENCE
THE NEBULAR HYPOTHESIS
From the preceding chapter, it appears that we have the five fol-
lowing phenomena to assist us in investigating the cause of the primitive
motions of the planetary system. The motions of the planets in the
same direction, and very nearly in the same plane ; the motions of the
satellites in the same direction as those of the planets ; the motions of
rotation of these different bodies and also of the sun, in the same direc-
tion as their motions of projection, and in planes very little inclined to
each other ; the small eccentricity of the orbits of the planets and satel-
lites; finally, the great eccentricity of the orbits of the comets, their
inclinations being at the same time entirely indeterminate.
Buffon is the only individual that I know of, who, since the discov-
ery of the true system of the world, endeavoured to investigate the ori-
gin of the planets and satellites. He supposed that a comet, by
impinging on the Sun, carried away a torrent of matter, which was
reunited far off, into globes of different magnitudes and at different dis-
tances from this star. These globes, when they cool and become hard-
ened, are the planets and their satellites. This hypothesis satisfies the
first of the five preceding phenomena; for it is evident that all bodies
thus formed should move very nearly in the plane which passes through
the centre of the Sun, and through the direction of the torrent of matter
which has produced them: but the four remaining phenomena appear
to me inexplicable on this supposition. Inded, the absolute motion of the
molecules of a planet ought to be in the same direction as the motion of
the centre of gravity; but it by no means follows from this, that the
motion of rotation of a planet should be also in the same direction. Thus
the Earth may revolve from east to west, and yet the absolute motion of
each of its molecules may be directed from west to east. This observa-
tion applies also to the revolution of the satellites, of which the direction
in the same hypothesis, is not necessarily the same as that of the motion
of projection of the planets.
The small eccentricity of the planetary orbits is a phenomenon, not
only difficult to explain on this hypothesis, but altogether inconsistent
with it. We know from the theory of central forces, that if a body which
moves in a re-entrant orbit about the Sun, passes very near the body of
the Sun, it will return constantly to it, at the end of each revolution.
EIGHTEENTH CENTURY SCIENCE 351
Hence it follows that if the planets were originally detached from the
Sun, they would touch it, at each return to this star ; and their orbits,
instead of being nearly circular, would be very eccentric. Indeed it
must be admitted that a torrent of matter detached from the Sun, cannot
be compared to a globe which just skims by its surface ; from the impul-
sions which the parts of this torrent receive from each other, com-
bined with their mutual attraction, they may, by changing the direction
of their motions, increase the distances of their perihelions from the
Sun. But their orbits should be extremely eccentric, or at least all the
orbits would not be q. p. circular, except by the most extraordinary
chance. Finally, no reason can be assigned on the hypothesis of Buffon,
why the orbits of more than one hundred comets, which have been
already observed, should be all very eccentric. This hypothesis, there-
fore, is far from satisfying the preceding phenomena. Let us consider
whether we can assign the true cause.
Whatever may be its nature, since it has produced or influenced
the direction of the planetary motions, it must have embraced them all
within the sphere of its action; and considering the immense distance
which intervenes between them, nothing could have effected this but a
fluid of almost indefinite extent. In order to have impressed on them
all a motion q. p. circular and in the same direction about the Sun, this
fluid must environ this star, like an atmosphere. From a consideration
of the planetary motions, we are therefore brought to the conclusion,
that in consequence of an excessive heat, the solar atmosphere originally
extended beyond the orbits of all the planets, and that it has successively
contracted itself within its present limits.
In the primitive state in which we have supposed the Sun to be, it
resembles those substances which are termed nebulae, which, when seen
through telescopes, appear to be composed of a nucleus, more or less
brilliant, surrounded by a nebulosity, which, by condensing on its sur-
face, transforms it into a star. If all the stars are conceived to be simi-
larly formed, we can suppose their anterior state of nebulosity to be
preceded by other states, in which the nebulous matter was more or less
diffuse, the nucleus being at the same time more or less brilliant. By
going back in this manner, we shall arrive at a state of nebulosity so dif-
fuse, that its existence can with difficulty be conceived.
For a considerable time back, the particular arrangement of some
stars visible to the naked eye, has engaged the attention of philosophers.
Mitchel remarked long since how extremely improbable it was that the
352 EIGHTEENTH CENTURY SCIENCE
stars composing the constellation called the Pleiades, for example,
should be confined within the narrow space which contains them, by the
sole chance of hazard ; from which he inferred that this group of stars,
and the similar groups which the heavens present to us, are the effects
of a primitive law of nature. These groups are a general result of the
condensation of nebulae of several nuclei ; for it is evident that the nebu-
lous matter being perpetually attracted by these different nuclei, ought
at length to form a group of stars, like to that of the Pleiades. The con-
densation of nebulae consisting of two nuclei, will in like manner form
stars very near to each other, revolving the one about the other like to
the double stars, whose respective motions have been already recognized.
But in what manner has the solar atmosphere determined the mo-
tions of rotation and revolution of the planets and satellies? If these
bodies had penetrated deeply into this atmosphere, its resistance would
cause them to fall on the Sun. We may therefore suppose that the plan-
ets were formed at its successive limits, by the condensation of zones of
vapours, which it must, while it was cooling, have abandoned in the
plane of its equator.
Let us resume the results which we have given in the tenth chapter
of the preceding book. The Sun's atmosphere cannot extend indefin-
itely ; its limit is the point where the centrifugal force arising from the
motion of rotation balances the gravity; but according as the cooling
contracts the atmosphere, and condenses the molecules which are near
to it, on the surface of the star, the motion of rotation increases ; for, in
virtue of the principle of areas, the sum of the areas described by the
radius vector of each particle of the Sun and its atmosphere, and pro-
jected on the plane of its equator, is always the same. Consequently the
rotation ought to be quicker, when these particles approach to the centre
of the Sun. The centrifugal force arising from this motion becoming
thus greater ; the point where the gravity is equal to it, is nearer to the
centre of the Sun. Supposing, therefore, what is natural to admit, that
the atmosphere extended at any epoch as far as this limit, it ought,
according as it cooled, to abandon the molecules, which are situated at
this limit, and at the successive limits produced by the increased rota-
tion of the Sun. These particles, after being abandoned, have continued
to circulate about this star, because their centrifugal force was balanced
by their gravity. But as this equality does not obtain for these mole-
cules of the atmosphere which are situated on the parallels to the Sun's
equator, these have come nearer by their gravity to the atmosphere ac-
EIGHTEENTH CENTURY SCIENCE 353
cording as it condensed, and they have not ceased to belong to it inas-
much as by their motion, they have approached to the plane of this
equator.
Let us now consider the zones of vapours, which have been suc-
cessively abandoned. These zones ought, according to all probability,
to form by their condensation, and by the mutual attraction of their par-
ticles, several concentrical rings of vapours circulating about the Sun.
The mutual friction of the molecules of each ring ought to accelerate
some and retard others, until they all had acquired the same angular
motion. Consequently the real velocities of the molecules which are far-
ther from the Sun, ought to be greatest. The following cause ought
likewise to contribute to this difference of velocities : The most distant
particles of the Sun, and which, by the effects of cooling and condensa-
tion, have collected so as to constitute the superior part of the ring, have
always described areas proportional to the times, because the central
force by which they are actuated has been constantly directed to this
star ; but this constancy of areas requires an increase of velocity, accord-
ing as they approach more to each other. It appears that the same cause
ought to diminish the velocity of the particles, which, situated near the
ring, constitute its inferior part.
If all the particles of a ring of vapours continued to condense with-
out separating, they would at length constitute a solid or a liquid ring.
But the regularity which this formation requires in all the parts of the
ring, and in their cooling, ought to make this phenomenon very rare.
Thus the solar system presents but one example of it ; that of the rings
of Saturn. Almost always each ring of vapours ought to be divided into
several masses, which, being moved with velocities which differ little
from each other, should continue to revolve at the same distance about
the Sun. These masses should assume a spheroidical form, with a
rotatory motion in the direction of that of their revolution, because their
inferior particles have a less real velocity than the superior ; they have
therefore constituted so many planets in a state of vapour. But if one of
them was sufficiently powerful, to unite successively by its attraction, all
the others about its centre, the ring of vapours would be changed into
one sole spheroidical mass, circulating about the Sun, with a motion of
rotation in the same direction with that of revolution. This last case has
been the most common; however, the solar system presents to us the
first case, in the four small planets which revolve between Mars and
Jupiter, at least unless we suppose with Olbers, that they originally
354 EIGHTEENTH CENTURY SCIENCE
formed one planet only, which was divided by an explosion into several
parts, and actuated by different velocities. Now if we trace the changes
which a further cooling ought to produce in the planets formed of
vapours, and of which we have suggested the formation, we shall see to
arise in the centre of each of them, a nucleus increasing continually, by
the condensation of the atmosphere which environs it. In this state, the
planet resembles the Sun in the nebulous state, in which we have first
supposed it to be ; the cooling should therefore produce at the different
limits of its atmosphere, phenomena similar to those which have been
described, namely, rings and satellites circulating about its centre in the
direction of its motion of rotation, and revolving in the same direction
on their axes. The regular distribution of the mass of rings of Saturn
about its centre and in the plane of its equator, results naturally from
this hypothesis, and, without it, is inexplicable. Those rings appear to
me to be existing proofs of the primitive extension of the atmosphere of
Saturn, and of its successive condensations. Thus, the singular phe-
nomena of the small eccentricities of the orbits of the planets and satel-
lites, of the small inclination of these orbits to the solar equator, and of
the identity in the direction of the motions of rotation and revolution of
all those bodies with that of the rotation of the Sun, follow the hypoth-
esis which has been suggested, and render it extremely probable. If the
solar system was formed with perfect regularity, the orbits of the bodies
which compose it would be circles, of which the planes, as well as those
of the various equators and rings, would coincide with the plane of the
solar equator. But we may suppose that the innumerable varieties
which must necessarily exist in the temperature and density of different
parts of these great masses, ought to produce the eccentricities of their
orbits, and the deviations of their motions, from the plane of this
equator.
In the preceding hypothesis, the comets do not belong to the solar
system. If they be considered, as we have done, as small nebulae, wan-
dering from one solar system to another, and formed by the condensa-
tion of the nebulous matter, which is diffused so profusely throughout
the universe, we may conceive that when they arrive in that part of
space where the attraction of the Sun predominates, it should force them
to describe elliptic or hyperbolic orbits. But as their velocities are
equally possible in every direction, they must move indifferently in all
directions, and at every posisble inclination to the elliptic; which is
conformable to observation. Thus the condensation of the nebulous
EIGHTEENTH CENTURY SCIENCE 355
matter, which explains the motions of rotation and revolution of the
planets and satellites in the same direction, and in orbits very little in-
clined to each other, likewise explains why the motions of the comets
deviate from this general law.
The great eccentricity of the orbits of the comets, is also a result of
our hypothesis. If those orbits are elliptic, they are very elongated,
since their greater axes are at least equal to the radius of the sphere
of activity of the Sun. But these orbits may be hyperbolic ; and if the
axes of these hyperbolae are not very great with respect to the mean
distance of the Sun from the Earth, the motion of the comets which
describe them will appear to be sensibly hyperbolic. However, with
respect to the hundred comets, of which the elements are known, not
one appears to move in a hyperbola ; hence the chances which assign a
sensible hyperbola, are extremely rare relatively to the contrary chances.
The comets are so small, that they only become sensible when their peri-
helion distance is inconsiderable. Hitherto this distance has not sur-
passed twice the diameter of the Earth's orbit, and most frequently, it
has been less than the radius of this orbit. We may conceive, that in or-
der to approach so near to the Sun, their velocity at the moment of their
ingress within its sphere of activity, must have an intensity and direc-
tion confined within very narrow limits. If we determine by the anal-
ysis of probabilities, the ratio of the chances which in these limits, assign
a sensible hyperbola to the chances which assign an orbit, which may
without sensible error be confounded with a parabola, it will be found
that there is at least six thousand to unity that a nebula which penetrates
within the sphere of the Sun's activity so as to be observed, will either
describe a very elongated ellipse, or an hyperbola, which, in consequence
of the magnitude of its axis will be as to sense confounded with a par-
abola in the part of its orbit which is observed. It is not therefore sur-
prising that hitherto no hyperbolic motions have been recognized.
The attraction of the planets, and perhaps also the resistance of the
ethereal media, ought to change several cometary orbits into ellipses, of
which the greater axes are much less than the radius of the sphere of
the solar activity. It is probable that such a change was produced in the
orbit of the comet of 1759, the greater axis of which was not more
than thirty-five times the distance of the Sun from the Earth. A still
greater change was produced in the orbits of the comets of 1770 and of
1805.
If in the zones abandoned by the atmosphere of the Sun, there are
356 EIGHTEENTH CENTURY SCIENCE
any molecules too volatile to be united to each other, or to the planets,
they ought in their circulation about this star to exhibit all the appear-
ances of the zodiacal light, without opposing any sensible resistance
to the different bodies of the planetary system, both on account of their
great rarity and also because their motion is very nearly the same as that
of the planets which they meet.
An attentive examination of all the circumstances of this system
renders our hypothesis still more probable. The primitive fluidity of the
planets is clearly indicated by the compression of their figure, conform-
ably to the laws of the mutual attraction of their molecules ; it is more-
over demonstrated by the regular diminution of gravity, as we proceed
from the equator to the poles. This state of primitive fluidity to which
we are conducted by astronomical phenomena, is also apparent from
those which natural history points out. But in order fully to estimate
them, we should take into account the immense variety of combinations
formed by all the terrestrial substances which were mixed together in
a state of vapour, when the depression of their temperature enabled
their elements to unite ; it is necessary likewise to consider the wonder-
ful changes which this depression ought to cause in the interior and at
the surface of the earth, in all its productions, in the constitution and
pressure of the atmosphere, in the ocean, and in all substances which
it held in a state of solution. Finally, we should take into account the
sudden changes, such as great volcanic eruptions, which must at differ-
ent epochs have deranged the regularity of these changes. Geology,
thus studied under the point of view which connects it with astronomy,
may, with respect to several objects, acquire both precision and
certainty.
One of the most remarkable phenomena of the solar system is the
rigorous equality which is observed to subsist between the angular mo-
tions of rotation and revolution of each satellite. It is infinity to unity
that this is not the effect of hazard. The theory of universal gravitation
makes infinity to disappear from this improbability, by shewing that it
is sufficient for the existence of this phenomenon, that at the commence-
ment these motions did not differ much. Then, the attraction of the
planet would establish between them a perfect equality ; but at the same
time it has given rise to a periodic oscillation in the axis of the satellite
directed to the planet, of which oscillation the extent depends on the
primitive difference between these motions. As the observations of
Mayer on the libration of the Moon, and those which Bouvard and
EIGHTEENTH CENTURY SCIENCE 357
Nicollet made for the same purpose, at my request, did not enable us to
recognize this oscillation; the difference on which it depends must be
extremely small, which indicates with every appearance of probability
the existence of a particular cause, which, has confined this difference
within very narrow limits, in which the attraction of the planet might
establish between the mean motions of rotation and revolution a rigid
equality, which at length terminated by annihilating the oscillation
which arose from this equality. Both these effects result from our
hypothesis; for we may conceive that the Moon, in a state of vapour,
assumed in consequence of the powerful attraction of the earth the form
of an elongated spheroid, of which the greater axis would be con-
stantly directed towards this planet, from the facility with which the
vapours yield to the slightest force impressed upon them. The terres-
trial attraction continuing to act in the same manner, while the Moon
is in a state of fluidity, ought at length, by making the two motions of
this satellite to approach each other, to cause their difference to fall
within the limits, at which their rigorous equality commences to estab-
lish itself. Then this attraction should annihilate, by little and little, the
oscillation which this equality produced on the greater axis of the spher-
oid directed towards the earth. It is in this manner that the fluids
which cover this planet, have destroyed by their friction and resistance
the primitive oscillations of its axis of rotation, which is only now sub-
ject to the nutation resulting from the actions of the Sun and Moon.
It is easy to be assured that the equality of the motions of rotation and
revolution of the satellites ought to oppose the formation of rings and
secondary satellites, by the atmospheres of these bodies. Consequently
observation has not hitherto indicated the existence of any such. The
motions of the three first satellites of Jupiter present a phenomenon
still more extraordinary than the preceding ; which consists in this, that
the mean longitude of the first, minus three times that of the second,
plus twice that of the third, is constantly equal to two right angles.
There is the ratio of infinity to one, that this equality is not the effect
of chance. But we have seen, that in order to produce it, it is sufficient,
if at the commencement, the mean motions of these three bodies ap-
proached very near to the relation which renders the mean motion of the
first, minus three times that of the second, plus twice that of the third,
equal to nothing. Then their mutual attraction rendered this ratio rig-
orously exact, and it has moreover made the mean longitude of the first
minus three times that of the second, plus twice that of the third, equal
358 EIGHTEENTH CENTURY SCIENCE
to a semicircumference. At the same time, it gave rise to a periodic
inequality, which depends on the small quantity, by which the mean
motions originally deviated from the relation which we have just an-
nounced. Notwithstanding all the care Delambre took in his observa-
tions, he could not recognize this inequality, which, while it evinces its
extreme smallness, also indicates, with a high degree of probability, the
existence of a cause which makes it to disappear. In our hypothesis,
the satellites of Jupiter, immediately after their formation, did not move
in a perfect vacuo ; the less condensible molecules of the primitive atmo-
spheres of the Sun and planet would then constitute a rare medium, the
resistance of which being different for each of the stars, might make
the mean motions to approach by degrees to the ratio in question ; and
when these movements had thus attained the conditions requisite, in
order that the mutual attraction of the three satellites might render
this relation accurately true, it perpetually diminished the inequality
which this relation originated, and eventually rendered it insensible. We
cannot better illustrate these effects than by comparing them to the
motion of a pendulum, which, actuated by a great velocity, moves in a
medium, the resistance of which is inconsiderable. It will first describe
a great number of circumstances ; but at length its motion of circulation
perpetually decreasing, it will be converted into an oscillatory motion,
which itself diminishing more and more, by the resistance of the me-
dium, will eventually be totally destroyed, and then the pendulum, hav-
ing attained a state of repose, will remain at rest for ever.
VOLTA
ALESSANDRO VOLTA was born at Como, Italy, February 18, 1745. In
1774 he became teacher of physics at Como and in 1779 professor at
Pavia. He early took an interest in electricity. About 1790 Galvani
discovered that the muscles of a frog contracted under the influence of
electricity. Galvani thought the frog's muscles to act as a Leyden jar,
Volta considered them rather a delicate electrometer. His experiments
to confirm this theory led him to the discovery of the voltaic pile, which
EIGHTEENTH CENTURY SCIENCE 359
produced the first constant current of electricity and had an enormous
influence on the science. Volta died in 1827.
NEW GALVANIC INSTRUMENT
On the Electricity Excited by the Mere Contact of Conducting
Substances of Different Kinds. By Mr. Alex Volta, F. R. S., Prof,
of Nat Philos. in the University of Pavia.
The chief of these results, and which comprehends nearly all the
others, is the construction of an apparatus which resembles in its effects,
viz. (such as giving shocks to the arms, &c.,) the Leyden phial, and still
better, electric batteries weakly charged; acting continually, or whose
charge, after each explosion, recharges itself again ; which in short
becomes perpetual, from one infallible charge, from one action or
impulse on the electric fluid ; but which besides differs essentially from
the other, by this continual action which is proper to it, and because that
instead of consisting, like the ordinary phials and electric batteries, in
one or more isolated plates, or thin layers of those bodies deemed the
only electrics, and armed with conductors or bodies called non-electrics,
this new apparatus is formed only of a number of these last bodies,
chosen even among the best conductors, and so the farthest removed,
according to the usual opinion, from the electric principle. This aston-
ishing apparatus is nothing but an assemblage of a number of good con-
ductors of a different kind, arranged in a certain manner. Thus, 30, 40,
60, or more pieces of copper, or better of silver, each applied to a piece
of tin, or still better of zinc, and an equal number of layers of water, or
of some other liquid which may be a better conductor than simple water,
as salt water, lye, &c., or of bits of card or leather, &c., soaked in such
liquids. Of such layers interposed between each couple or combination
of two different metals, one such alternate series, and always in the same
order, of these three kinds of conductors, is all that constitutes M.
Volta's new instrument ; which imitates so well the effects of the Leyden
phial or electric' batteries ; not indeed with the force and explosions of
these, when highly charged ; but only equalling the effects of a battery
charged to a very weak degree, of a battery, however, having an im-
mense capacity, but which besides infinitely surpasses the virtue and the
power of these same batteries ; as it has no need, like them, of being
charged beforehand, by means of a foreign electricity ; and as it is
360 EIGHTEENTH CENTURY SCIENCE
capable of giving the usual commotion as often as ever it is properly
touched. This apparatus, as it resembles more the natural electric organ
of the torpedo, or of the electric eel than the Leyden phial and the ordi-
nary electric batteries, M. Volta calls the artificial electric organ. For
the construction of this instrument, M. Volta provides some dozens of
small, round metal plates of copper, or tin, or best of silver, about an
inch in diameter, like shillings or half-crowns, and an equal number of
plates of tin, or much better of zinc, of the same shape and size. These
pieces he places exactly one upon another, forming a column, pillar or
pile. He provides also as many round pieces of card, or leather, or such
like spongy matter, capable of imbibing and retaining much of the water,
or other liquid, when soaked in it. These soaked roullets or circles are
to be a little less in diameter than the small metal discs or plates, that
they may not jut out beyond them. All these discs are then placed hori-
zontally on a table, one over another continually alternating, in a pile as
high as will well support itself without tottering and falling down:
beginning with a plate of either of the metals, as for instance, the silver,
then upon that one of zinc, over which is to be put the soaked card ; then
other three discs, over these in the same order, viz. a silver, next a zinc,
and then another moistened card, &c.
After having raised the pile to about 20 of these stages or triads
of plates, it will be already capable, not only of affecting Cavallo's elec-
trometer, assisted by the condenser, so as to raise it 10 or 15°, charging
it by a simple touching, so as to cause it to give a spark, &c., as also to
strike the fingers with which we touch the top or bottom of the column,
with several small snaps, the fingers being wetted with water. But if to
the 20 sets of triplets of the plates be added 20 or 30 more, disposed in
the same order, the actions of the extended pile will be much stronger,
find be felt through the arms up to the shoulders ; and by continuing the
touchings, the pains in the hands become insupportable.
M. Volta constructs and combines his apparatus in various ways
and forms, more or less powerful, convenient or amusing. One is as
follows (Fig. i, pi. 13,), which he calls a couronne de tosses. He dis-
poses in a row a number of cups of wood, or earth, or glass, or any thing
but metal, half filled with pure water, or salt water or lye ; these are all
made to communicate in a kind of chain, by several metallic arcs of
which one arm or link, Aa, or only the extremity A, immersed in one of
the cups, is of copper, or of copper silvered, and the other Z, immersed
in the following cup, is of tin, or rather of zinc, the other two being
EIGHTEENTH CENTURY SCIENCE 361
soldered together near the crown of the arch. It is evident that a series
of these cups, thus connected together, either in a straight or curvd line,
by the two metals and the intermediate liquid, is similar to the pillar or
pile before described, and consequently will exhibit similar effects. Thus,
to produce commotion or sensation in the hands and arms, we need only
dip one hand into one of the cups and the finger of the other hand into
another cup, sufficiently far from the former ; and the action will be so
much the stronger as the two cups are farther asunder, or have the more
intermediate cups ; and consequently the greatest by touching the first
and the last in the chain.
As to the structure in the other method, by the column or pile, Mr.
Volta found out various ways to prolong and extend it, in multiplying
the metal plates without shaking it down ; to render this instrument con-
venient, portable and durable; and among others, the three methods
exhibited on figs. 2, 3, 4, pi. 13. In fig. 2, mmmm, are upright bars or
rods, to the number of three or four, or more, erected from the bottom of
the pile, and extended to a convenient height, inclosing the pile like a
cage, to prevent its falling. These rods may be either of glass, wood or
metal ; only, in this last case, they must be hindered from touching the
metal plates ; which may be done either by covering each metal rod with
a glass tube or by interposing between them and the pile some bands of
cere-cloth or oiled paper or simple paper, or any imperfect conducting
substance.
But the best expedient for forming the instrument of a great num-
ber of plates, as of 60, 80, or 1,000, is to divide the pile into two or more,
as in the figures 3 and 4, where the pieces have all their respective posi-
tions or communications, as if it was one pile only, plied and turned. In
all these figures the different metal plates are denoted by the letters A
and Z, the initials of argent and zinc, and of the wet discs of card, or
leather, &c., interposed at each pair of those metals, by a layer or band
shaded black. The dotted lines show the contact of each couple of metal
plates, A and Z, where they may be conveniently soldered together, cc,
cc, cc, are metal plates forming the communication between one column,
or section of a column, and another ; and b, b, b, b, b, are basins of water,
in communication with the bottoms or extremities of the piles.
M. Volta concludes with various remarks and cautions in using
this instrument ; showing that it is perpetual in its virtue, renewing its
charge spontaneously, and serving most of the purposes of the ordinary
electrical machines, and even affecting and manifesting its power by
most of the human senses, viz. feeling, tasting, hearing, and seeing.
V 6-23
362
RELIGIOUS MOVEMENTS
JOHN WESLEY
JOHN WESLEY was born June 17 (June 28 by old style), 1703, at
Ep worth. He entered Oxford in 1720, and in 1726 became a fellow of
Lincoln. In 1729, after an absence of two years, he returned to Oxford
and began to take in pupils. Just before his return his brother Charles
had induced a few students to meet him for weekly communion, and
with the coming of John, the characteristics of the society became quite
pronounced, for the members, besides taking weekly communion, began
studying the Greek Testament together, observing regular fasting and
private devotion, and visiting prisoners and the sick. It was during this
period that they were given such sobriquets as "the Godly" and "Meth-
odists," and the society at first fell off in numbers because of the crit-
icism it had aroused.
In 1736 Wesley went to Georgia as a missionary. About this time
he came somewhat under the influence of the Moravians, and had
already accepted the doctrine of salvation by faith. Soon after his return
to England in 1738, he felt that he had undergone his first real conver-
sion, had actually been born in the "new birth." This doctrine of an
actual conscious conversion through faith he commenced to preach as an
evangelist along with his brother and Whitefield.
The Episcopal clergy began to discourage the new movement, so
the evangelists began addressing the crowds in the open fields. In 1739
the societies first joined under the direct charge of Wesley, although
RELIGIOUS MOVEMENTS 363
all this time and until after Wesley's death Methodism considered itself
only a society within the Episcopal church.
In 1740 the churches mostly refused the sacrament to the members
of the society and the Wesleys administered it themselves. In 1741, lay
preachers were called out to help them, and the next year leaders of the
classes were appointed. The whole organization was under the entire
charge of Wesley and continued so until his death. The first conference
was held in 1744, and the powers of that body gradually increased until
after Wesley's death it was ready to assume the control of the church.
In 1784 the American societies were organized as a church, inde-
pendent of the Episcopalians and of English Methodism.
Wesley died in 1791. We give below his most important beliefs.
THE EARLY METHODISTS
The following queries concerning the Methodists were sent, I ap-
prehend, from Holland or Germany to some person in England.
The answer to each is in Mr. Wesley's handwriting; and the date
prefixed is 1741. But if this be the true date, I conjecture, from the
answer to the fourth and fifth query, that it must have been very early
in this year, before Mr. Wesley and Mr. Whitefield separated on the
doctrine of predestination. However, not being able to ascertain the
date exactly, I have referred them to this place.
Quest, i. Whether the number of Methodists is considerable,
among the students and learned men?
Ans. "The number of Methodists is not considerable, among the
students and learned men."
2. Whether at Oxford, where the Methodists first sprung up, there
be still many of them among the scholars ?
"There are very few of them now left, among the scholars at
Oxford."
3. Whether they are all of one mind, and whether they have the
same principles ? Especially, 4. Whether those Methodists that are still
at Oxford, approve of the sentiments and actions of Mr. Whitefield and
Messrs. Wesleys ?
"They are all of the same principles with the Church of England
as laid down in her Articles and Homilies; and, 4. Do accordingly
approve of the sentiments of Mr. Whitefield and Mr. Wesley, and of
364 RELIGIOUS MOVEMENTS
their publishing them elsewhere, since they have been shut out of the
churches."
5. How they came to revive those doctrines, hitherto neglected by
the clergy of the Church of England, of predestination, the new birth,
and justification by faith alone? And 6. Whether they have the same
from the Moravian brethren ?
"Predestination is not a doctrine taught by the Methodists. But
they do teach that men must be born again, and that we are saved
through faith: and 6. "The latter of these they learned from some of
the Moravian brethren ; the former by reading the New Testament."
7. Whether they be orthodox in other doctrinal points ; and whether
they lead an unblameable Christian life.
"They openly challenge all that hear them to answer those ques-
tions, 'Which of you convinceth me of sin ?' Or, of teaching any doc-
trine contrary to the Scripture? And the general accusation against
them is, that they are righteous overmuch."
8. Whether they strictly regulate themselves according to the rule
and discipline of the Moravian brethren ; except that they still keep and
observe the outward worship according to the Church of England ?
"They do not regulate themselves according to the discipline of the
Moravians, but of the English church."
9. Whether they do any real good among the common people?
"Very many of the common people, among whom they preach, were
profane swearers, and now fear an oath; were gluttons, or drunkards,
and are now temperate ; were whoremongers, and are now chaste ; were
servants of the devil, and are now servants of God."
10. Why the bishops do not effectually inhibit them, and hinder
their field and street preaching ?
"The bishops do not inhibit their field and street preaching; i.
Because there is no law in England against it ; 2. Because God does not
yet suffer them to do it without law."
11. Whether the Archbishop of Canterbury is satisfied with them;
as we are told ?
"The Archbishop of Canterbury is not satisfied with them ; especi-
ally since Mr. Molther, in the name of the Moravian church, told his
Grace their disapprobation of them; and in particular of their field
preaching."
12. Whether their private assemblies or societies are orderly and
edifying ?
REUGIOUS MOVEMENTS 365
"Their private assemblies and societies are orderly, and many say
they find them edifying."
13. What opinion the Presbyterians, and particularly Dr. Watts,
has of them ?
"Most of the Presbyterians, and most all other denominations, are
of the opinion, much religion hath made them mad."
14. Whether there are any Methodists among the Episcopal clergy
of the Church of England ?
"Mr. Whitefield, Hutchins, Robson, and the Messrs. Wesleys, and
several others, are priests of the Episcopal Church of England." —
Whitehead's "John and Charles Wesley."
GENERAL RULES OF THE SOCIETY
On the i Qtli Wesley reached Newcastle; and here and in the neigh-
boring towns and villages he spent near six weeks in preaching and ex-
horting in praying and conversing with the people, and in regulating the
societies. A great number of these societies were already formed exactly
on the same principles, in various parts of the kingdom, though at a
considerable distance one from another. But hitherto no general rules
had been made to govern the whole. The two brothers, therefore, now
drew up a set of rules which should be observed by the members of all
their societies, and, as it were, unite them all into one body; so that a
member at Newcastle knew the rules of the society in London, as well as
at the place where he resided. They were printed under the title of
"The Nature, Design, and General Rules of the United Societies, in
London, Bristol, Newcastle-upon-Tyne," &c., and here it will be proper
to insert them.
I. They state the nature and design of a Methodist society in the
following words : "Such a society is no other than a company of men,
having the form and seeking the power of godliness ; united in order to
pray together, to receive the word of exhortation, and to watch over one
another in love, that they may help each other to work out their salva-
tion.
"That it may the more easily be discerned whether they are indeed
working out their own salvation, each society is divided into smaller
companies, called classes, according to their respective places of abode.
There are about twelve persons in every class, one of whom is styled the
leader. It is his business: i. To see each person in his class once a
366 RELIGIOUS MOVEMENTS
week at least, in order to inquire how their souls prosper. To advise,
reprove, comfort or exhort, as occasions require ; to receive what they
are willing to give toward the relief of the poor. 2. To meet the min-
ister and the stewards of the society once a week, in order to inform the
minister of any that are sick ; or of any that walk disorderly, and will
not be reproved ; to pay to the stewards what they have received of their
several classes the week preceding; and to show their account of what
each person has contributed.
II. "There is only one condition previously required in those who
desire admission into these societies, a desire 'to flee from the wrath to
come,' to be saved from their sins. But wherever this is really fixed in
the soul, it will be shown by its fruits. It is therefore expected of all who
continue therein that they should continue to evidence their desire of
salvation.
1. "By doing no harm, by avoiding evil in every kind; especially
that which is most generally practiced, such as
"The taking the name of God in vain ; the profaning the day of the
Lord, either by doing ordinary work thereon, or by buying or selling ;
drunkenness; buying or selling spirituous liquors, or drinking them,
unless in cases of extreme necessity; fighting, quarreling, brawling;
brother going to law with brother ; returning evil for evil, or railing for
railing ; the using many words in buying or selling ; the buying or sell-
ing uncustomed goods; the giving or taking things on usury; i. e.,
unlawful interest; uncharitable or unprofitable conversation; particu-
larly speaking evil of magistrates or ministers ; doing to others as we
would not they should do unto us ; doing what we know is not for the
glory of God : as
"The putting on gold, or costly apparel ; the taking such diversions
as cannot be used in the name of the Lord Jesus; the singing those
songs, or reading those books, which do not tend to the knowledge or
love of God; softness, or needless self-indulgence; laying up treasures
upon earth; borrowing without a probability of paying; or taking up
goods without a probability of paying for them.
"It is expected of all who continue in these societies, that they
should continue to evidence their desire of salvation :
2. "By doing good, by being in every kind merciful after their
power ; as they have opportunity, doing good of every possible sort, as
far as is possible to all men ; to their bodies, of the ability which God
giveth ; by giving food to the hungry, by clothing the naked, by visiting
REUGIOUS MOVEMENTS 367
or helping them that are sick or in prison. To their souls, by instructing,
reproving, or exhorting all they have intercourse with ; trampling under
foot that enthusiastic doctrine of devils, that 'we are not to do good
unless our hearts be free to it.'
"By doing good especially to them that are of the household of
faith, or groaning so to be ; employing them preferably to others ; buying
one of another ; helping each other in business ; and so much the more,
because the world will love its own, and them only.
"By all possible diligence and frugality, that the gospel be not
blamed; by running with patience the race that is set before them,
'denying themselves and taking up their cross daily' ; submitting to bear
the reproach of Christ, to be as the filth and off-scouring of the world ;
and looking that men should 'say all manner of evil of them falsely for
the Lord's sake.'
"It is expected of all who desire to continue in these societies, that
they should continue to evidence their desire of salvation.
3. "By attending upon all the ordinances of God. Such are the
public worship of God; the ministry of the word, either read or ex-
pounded ; the supper of the Lord ; family and private prayer ; searching
the Scriptures ; and fasting and abstinence.
"These are the general rules of our societies ; all of which we are
taught of God to observe, even in His written word, the only rule, and
the sufficient rule, both of our faith and practice. And all these we
know His Spirit writes on every truly awakened heart. If there be any
amongst us who observe them not, who habitually break any of them, let
it be made known unto them who watch over that soul, as they that must
give an account. We will admonish him of the error of his ways : we
will bear with him for a season. But if he repent not, he hath no more
place with us. We have delivered our own soul.
"JOHN WESLEY.
"CHARLES WESLEY."
May i, 1743 .
THE DOCTRINE OF JUSTIFICATION
I. Q. I. "What is it to be justified?
A. "To be pardoned and received into God's favor; into such a
state, that if we continue therein, we shall be finally saved.
368 RELIGIOUS MOVEMENTS
Q. 2. "Is faith the condition of justification?
A. "Yes ; for every one who believeth not is condemned ; and every
one who believes is justified.
Q. 3. "But must not repentance and works meet for repentance go
before this faith?
A. "Without doubt : if by repentance you mean conviction of sin ;
and by works meet for repentance, obeying God as far as we can, for-
giving our brother, leaving off from evil, doing good and using His
ordinances according to the power we have received.
Q. 4. "What is faith?
A. "Faith in general is a divine, supernatural elenchos of things not
seen ; *. e. of past, future, or spiritual things : it is a spiritual sight of God
and the things of God.
"First, a sinner is convinced by the Holy Ghost, 'Christ loved me
and gave Himself up for me.' This is that faith by which he is justified
or pardoned, the moment he receives it. Immediately the same spirit
bears witness, 'Thou art pardoned : thou hast redemption in His blood.'
And this is saving faith, whereby the love of God is shed abroad in his
heart.
Q. 5. "Have all Christians this faith ? May not a man be justified
and not know it ?
A. "That all true Christians have such a faith as implies an assur-
ance of God's love, appears from Rom. viii. 15.; Eph. iv. 32.; II. Cor.
xiii. 5. ; Heb. viii. 10 ; I. John iv. 10, v. 19. And that no man can be jus-
tified and not know it, appears further from the nature of the thing. For
faith after repentance is ease after pain, rest after toil, light after dark-
ness. It appears also from the immediate, as well as distant fruits
thereof.
Q. 6. "But may not a man go to heaven without it?
A. "It does not appear from holy writ that a man who hears the
gospel can (Mark xvi. 16) : whatever a heathen may do. Rom. ii. 14.
Q. 7. "What are the immediate fruits of justifying faith?
A. "Peace, joy, love, power over all outward sin, and power to keep
down inward sin.
Q. 8. "Does any one believe, who has not the witness in himself, or
any longer than he sees, loves and obeys God ?
A. "We apprehend not ; seeing God being the very essence of faith ;
love and obedience the inseparable properties of it.
Q. 9. "What sins are consistent with justifying faith?
RELIGIOUS MOVEMENTS 369
A. "No wilful sin. If a believer wilfully sins, he casts away his
faith. Neither is it possible he should have justifying faith again, with-
out previously repenting.
Q. 10. "Must every believer come into a state of doubt or fear, or
darkness ? Will he do so, unless by ignorance or unfaithfulness ? Does
God otherwise withdraw Himself ?
A. "It is certain a believer need never again come into condemna-
tion. It seems he need not come into a state of doubt or fear, or dark-
ness : and that (ordinarily at least) he will not, unless by ignorance or
unfaithfulness. Yet it is true that the first joy does seldom last long :
that it is commonly followed by doubts and fears; and that God fre-
quently permits great heaviness before any large manifestation of Him-
self.
Q. 1 1. "Are works necessary to the continuance of faith?
A. "Without doubt; for a man may forfeit the free gift of God,
either by sins of omission or commission.
Q. 12. "Can faith be lost, but for want of works?
A. "It cannot but through disobedience.
Q. 13. "How is faith made perfect by works?
A. "The more we exert our faith, the more it is increased. To him
that hath shall be given.
Q. 14. "St. Paul says, Abraham was not justified by works. St.
James, he was justified by works. Do they not contradict each other ?
A. "No : i. Because they do not speak of the same justification. St.
Paul speaks of that justification which was when Abraham was seventy-
five years old, above twenty years before Isaac was born. St. James of
that justification which was when he offered up Isaac on the altar.
2. "Because they do not speak of the same works. St. Paul speak-
ing of works that precede faith ; St. James of works that spring from it.
Q. 15. "In what sense is Adam's sin imputed to all mankind ?
A. "In Adam all die, i. e., I. Our bodies then became mortal.
2. Our souls died, i. e. were disunited from God. And hence, 3. We are
all born with a sinful, devilish nature : by reason whereof, 4. We are
children of wrath, liable to death eternal. Rom. v. 18. ; Eph. ii. 3.
Q. 16. "In what sense is the righteousness of Christ imputed to all
mankind, or to believers ?
A. "We do not find it expressly affirmed in Scripture that God
imputes the righteousness of Christ to any. Although we do find that
faith is imputed to us for righteousness.
370 RELIGIOUS MOVEMENTS
"That text, 'As by one man's disobedience all men were made sin-
ners, so by the obedience of one, all were made righteous/ we conceive
means, by the merits of Christ, all men are cleared from the guilt of
Adam's actual sin.
"We conceive further, that through the obedience and death of
Christ, i. The bodies of all men become immortal after the resurrection.
2. Their souls receive a capacity of spiritual life; and, 3. An actual
spark or seed thereof. 4. All believers become children of grace, recon-
ciled to God, and 5, made partakers of the divine nature.
Q. 17. "Have we not then unawares leaned too much towards Cal-
vinism ?
A. "We are afraid we have.
Q. 18. "Have we not also leaned towards Antinomianism ?
A. "We are afraid we have.
Q. 19. "What is Antinomianism ?
A. "The doctrine which makes void the law through faith.
Q. 20. "What are the main pillars hereof?
A. I. "That Christ abolished the moral law. 2. That therefore
Christians are not obliged to observe it. 3. That one branch of Chris-
tian liberty, is liberty from obeying the commandments of God. 4. That
it is bondage, to do a thing, because it is commanded, or forbear it
because it is forbidden. 5. That a believer is not obliged to use the
ordinances of God or to do good works. 6. That a preacher ought not
to exhort to good works: not unbelievers, because it is hurtful; not
believers, because it is needless.
Q. 21. "What was the occasion of St. Paul's writing his Epistle to
the Galatians ?
A. "The coming of certain men amongst the Galatians, who taught,
Except ye be circumsised and keep the law of Moses ye cannot be saved.
Q. 22. "What is the main design therein ?
A. "To prove, I. That no man can be justified or saved by the
works of the law, either moral or ritual. 2. That every believer is jus-
tified by faith in Christ without the works of the law.
Q. 23. "What does he mean by the works of the law. Gal. ii. 16, &c.
A. "All works which do not spring from faith in Christ.
Q. 24. "What by being under the law ? Gal. iii. 23.
A. "Under the Mosaic dispensation.
Q. 25. "What law has Christ abolished ?
A. "The ritual law of Moses.
RELIGIOUS MOVEMENTS 371
Q. 26. "What is meant by liberty? Gal. v. I.
A. "Liberty, I. From the law; 2. From sin.
II. Q. i. "How comes what is written on this subject to be so
intricate and obscure? Is this obscurity from the nature of the thing
itself? Or from the fault or weakness of those who have generally
treated of it ?
A. "We apprehend this obscurity does not arise from the nature
of the subject, but partly from the extreme warmth of most writers who
have treated of it.
Q. 2. "We affirm faith in Christ is the sole condition of justifica-
tion. But does not repentance go before that faith? Yea, and (suppos-
ing there be opportunity for them) fruits or works meet for repentance?
A. "Without doubt they do.
Q. 3. "How then can we deny them to be conditions of justifica-
tion ? Is not this a mere strife of words ?
A. "It seems not, though it has been grievously abused. But so the
abuse cease, let the use remain.
Q. 4. "Shall we read over together Mr. Baxter's aphorisms con-
cerning justification?
A. "By all means: which were accordingly read. And it was
desired, that each person present would in the afternoon consult the
Scriptures cited therein, and bring what objections might occur the next
morning.
Q. 5. "Is an assurance of God's pardoning love absolutely neces-
sary to our being in His favor ? Or may there possibly be some exempt
cases?
A. "We dare not positively say there are not.
Q. 6. "Is such an assurance absolutely necessary to inward and
outward holiness ?
A. "To inward, we apprehend it is ; to outward holiness, we incline
to think it is not.
Q. 7. "Is it indispensably necessary to final salvation?
A. "Love hopeth all things. We know not how far any may fall
under the case of invincible ignorance.
Q. 8. "But what can we say of one of our own society, who dies
without it, as J. W. at London ?
A. "It may possibly be an exempt case (if the fact was really so).
But we determine nothing. We leave his soul in the hands of Him that
made it.
372 RELIGIOUS MOVEMENTS
Q. 9. "Does a man believe any longer than he sees a reconciled
God?
A. "We conceive not. But we allow there may be infinite degrees
in seeing God : even as many as there are between him who sees the sun
when it shines on his eyelids closed and him who stands with his eyes
wide open, in the full blaze of his beams.
Q. 10. "Does a man believe any longer than he loves God ?
A. "In no wise. For neither circumcision or uncircumcision avails,
without faith working by love.
Q. ii. "Have we duly considered the case of Cornelius? Was he
not in the favor of God, when his prayers and alms came up for a
memorial before God ? *. e., before he believed in Christ ?
A. "It does seem that he was, in some degree. But we speak not of
those who have not heard the gospel.
Q. 12. "But were those works of his splendid sins?
A. "No ; nor were they done without the grace of Christ.
Q. 13. "How then can we maintain that all works done before we
have a sense of the pardoning love of God are sin ? And, as such, an
abomination to Him ?
A. "The works of him who has heard the gospel and does not
believe, are not done as God hath willed and commanded them to be
done. And yet we know not how to say that they are an abomination to
the Lord in him who feareth God, and from that principle does the best
he can.
Q. 14. "Seeing there is so much difficulty in this subject, can we
deal too tenderly with them that oppose us ?
A. "We cannot ; unless we were give up any part of the truth of
God.
Q. 15. "Is a believer constrained to obey God?
A. "At first he often is. The love of Christ constraineth him.
After this he may obey, or he may not ; no constraint being laid upon
him.
Q. 16. "Can faith be lost but through disobedience?
A. "It cannot. A believer first inwardly disobeys, inclines to sin
with his heart ; then his intercourse with God is cut off, i. e., his faith is
lost. And after this he may fall into outward sin, being now weak and
like another man.
Q. 17. "How can such a one recover faith?
A. "By repenting and doing the first works. Rev. ii. 5.
RELIGIOUS MOVEMENTS 373
Q. 18. "Whence is it that so great a majority of those who believe
fall more or less into doubt or fear ?
A. "Chiefly from their own ignorance or unfaithfulness: often
from their not watching unto prayer; perhaps sometimes from some
defect or want of the power of God in the preaching they hear.
Q. 19. "Is there not a defect in us? Do we preach as we did at
first ? Have we not changed our doctrines ?
A. i. "At first we preached almost wholly to unbelievers. To those
therefore we spake almost continually of remission of sins through the
death of Christ, and the nature of faith in His blood. And so we do
still, among those who need to be taught the first elements of the gospel
of Christ :
2. "But those in whom the foundation is already laid, we exhort to
go on to perfection : which we did not see so clearly at first ; although we
occasionally spoke of it from the beginning.
3. "Yet we now preach, and that continually, faith in Christ as the
prophet, priest and king, at least as clearly, as strongly and as fully as
we did six years ago.
Q. 20. "Do not some of our assistants preach too much of the
wrath, and too little of the love of God ?
A. "We fear they have leaned to that extreme ; and hence some of
their hearers may have lost the joy of faith.
Q. 21. "Need we ever preach the terrors of the Lord to those who
know they are accepted of Him ?
A. "No ; it is folly to do so ; for love is to them the strongest of all
motives.
Q. 22. "Do we ordinarily represent a justified state so great and
happy as it is ?
A. "Perhaps not. A believer walking in the light is inexpressibly
great and happy.
Q. 23. "Should we not have a care of depreciating justification, in
order to exalt the state of full sanctification ?
A. "Undoubtedly we should beware of this : for one may insensibly
slide into it.
Q. 24. "How shall we effectually avoid it?
A. "When we are going to speak of entire sanctification, let us first
describe the blessings of a justified state as strongly as possible.
Q. 25. "Does not the truth of the gospel lie very near both to Cal-
vinism and Antinomianism ?
374 REUGIOUS MOVEMENTS
A. "Indeed it does : as it were, within a hair's breadth. So that it
is altogether foolish and sinful, because we do not quite agree either with
one or the other ; to run from them as far as ever we can.
Q. 26. "Wherein may we come to the very edge of Calvinism ?
A. i. "In ascribing all good to the free grace of God ; 2. In denying
all natural free will and all power antecedent to grace ; and 3. In exclud-
ing all merit from man ; even for what he has or does by the grace of
God.
Q. 27. "Wherein may we come to the edge of Antinomianism ?
A. i. "In exalting the merits and love of Christ. 2. In rejoicing ever-
more.
Q. 28. "Does faith supersede (set aside the necessity of) holiness
or good works ?
A. "In no wise. So far from it that it implies both, as a cause does
its effects.
III. Q. i. "Can an unbeliever (whatever he is in other respects)
challenge anything of God's justice?
A. "Absolutely nothing but hell. And this is a point which we can-
not too much insist on.
Q. 2. "Do we empty men of their own righteousness, as we did at
first ? Do we sufficiently labor when they begin to be convinced of sin,
to take away all they lean upon ? Should we not then endeavor with all
our might to overturn their false foundations ?
A. "This was at first one of our principal points. And it ought to
be so still. For till all other foundations are overturned they cannot build
upon Christ.
Q. 3. "Did we not then purposely throw them into convictions?
Into strong sorrow and fear? Nay, did we not strive to make them
inconsolable ? Refusing to be comforted ?
A. "We did. And so we should do still. For the stronger the con-
viction the speedier is the deliverance. And none so soon receive the
peace of God as those who steadily refuse all other comfort.
Q. 4. "What is sincerity?
A. "Willingness to know and do the whole will of God. The low-
est species thereof seems to be faithfulness in that which is little.
Q. 5. "Has God any regard to man's sincerity ?
A. "So far, that no man in any state can possibly please God with-
out it ; neither indeed in any moment wherein he is not sincere.
Q. 6. "But can it be conceived that God has any regard to the sin-
cerity of an unbeliever ?
RELIGIOUS MOVEMENTS 375
A. "Yes ; so much that if he perseveres therein, God will infallibly
give him faith.
Q. 7. "What regard may we conceive him to have to the sincerity
of a believer?
A. "So much, that in every sincere believer he fulfills all the great
and precious promises.
Q. 8. "Whom do you term a sincere believer ?
A. "One that walks in the light, as God is in the light.
Q. 9. "Is sincerity the same with a single eye?
A. "Not altogether. The latter refers to our intention ; the former
to our will or desires.
Q. 10. "Is it not all in all ?
A. "All will follow persevering sincerity. God gives everything
with it ; nothing without it.
Q. ii. "Are not sincerity and faith equivalent terms ?
A. "By no means. It is at least as nearly related to works as it is to
faith. For example : who is sincere before he believes ? He that then
does all he can : he that, according to the power he has received, brings
forth 'fruits meet for repentance.' Who is sincere after he believes? He
that, from a sense of God's love, is zealous of all good works.
Q. 12. "Is not sincerity what St. Paul terms a willing mind?
II. Cor. viii. 12.
A. "Yes ; if that word be taken in a general sense. For it is a con-
stant disposition to use all the grace given.
Q. 13. "But do we not then set sincerity on a level with faith?
A. "No. For we allow a man may be sincere and not be justified,
as he may be penitent and not be justified (not as yet), but he cannot
have faith and not be justified. The very moment he believes he is jus-
tified.
Q. 14. "But do we not give up faith and put sincerity in its place,
as the condition of our acceptance with God ?
A. "We believe it is one condition of our acceptance, as repentance
likewise is. And we believe it a condition of our continuing in a state of
acceptance. Yet we do not put it in the place of faith. It is by faith the
merits of Christ are applied to my soul. But if I am not sincere, they
are not applied.
Q. 15. "Is not this that going about to establish your own right-
ousness, whereof St. Paul speaks, Rom. x. 4?
A. "St. Paul there manifestly speaks of unbelievers, who sought to
376 RELIGIOUS MOVEMENTS
be accepted for the sake of their own righteousness. We do not seek to
be accepted for the sake of our sincerity; but through the merits of
Christ alone. Indeed, so long as any man believes, he cannot go about
(in St. Paul's sense) 'to establish his own righteousness.'
Q. 16. "But do you consider that we are under the covenant of
grace ? And that the covenant of works is now abolished ?
A. "All mankind were under the covenant of grace from the very
hour that the original promise was made. If by the covenant of works
you mean that of unsinning obedience made with Adam before the fall ;
no man but Adam was ever under that covenant : for it was abolished
before Cain was born. Yet it is not so abolished but that it will stand,
in a measure, even to the end of the world, i. e., if we do this, we s.hall
live ; if not, we shall die eternally ; if we do well, we shall live with God
in glory ; if evil, we shall die the second death. For every man shall be
judged in that day, and rewarded according to his works.
Q. 17. "What means then, 'to him that believeth, his faith is
counted for righteousness ?'
A. "That God forgives him that is unrighteous as soon as he
believes, accepting His faith instead of perfect righteousness. But then
observe, universal righteousness follows, though it did not precede faith.
Q. 1 8. "But is faith thus counted to us for righteousness, at what-
soever time we believe?
A. "Yes. In whatsoever moment we believe, all our past sins van-
ish away. They are as though they had never been, and we stand clear
in the sight of God.
Q. 19. "Are not the assurance of faith, the inspiration of the Holy
Ghost and the revelation of Christ in us, terms nearly of the same
import?
A. "He that denies one of them must deny all ; they are so closely
connected together.
Q. 20. "Are they ordinarily, where the pure gospel is preached,
essential to our acceptance ?
A. "Undoubtedly they are; and as such, to be insisted on in the
strongest terms.
Q. 21. "Is not the whole dispute of salvation by faith, or by works,
a mere strife of words ?
A. "In asserting salvation by faith we mean this: I. That pardon
(salvation begun) is received by faith, producing works. 2. That holi-
ness (salvation continued) is faith working by love. 3. That heaven
(salvation finished) is the reward of this, faith.
RELIGIOUS MOVEMENTS 377
"If you who assert salvation by works, or by faith and works, mean
the same thing (understanding by faith the revelation of Christ in us,
by salvation, pardon, holiness, glory,) we will not strive with you at all.
If you do not, this is not a strife of words : but the very vitals, the
essence of Christianity is the thing in question.
Q. 22. "Wherein does our doctrine now differ from that we
preached while at Oxford ?
A. "Chiefly in these two points : i. We then knew nothing of that
righteousness of faith, in justification; nor 2. Of the nature of faith
itself as implying consciousness of pardon.
Q. 23. "May not some degree of the love of God go before a dis-
tinct sense of justification?
A. "We believe it may.
Q. 24. "Can any degree of sanctification or holiness ?
A. "Many degrees of outward holiness may : yea, and some degrees
of meekness, and several other tempers which would be branches of
Christian holiness, but that they do not spring from Christian principles.
For the abiding love of God cannot spring, but from faith in a pardoning
God. And no true Christian holiness can exist without that love of God
for its foundation.
Q. 25. "Is every man, as soon as he believes, a new creature, sanc-
tified and pure in heart ? Has he then a new heart ? Does Christ dwell
therein ? And is he a temple of the Holy Ghost ?
A. "All these things may be affirmed of every believer in a true
sense. Let us not therefore contradict those who maintain it. Why
should we contend about words ?"
VOLTAIRE
FRANCOIS MARIE AROUET DE VOLTAIRE was born at Paris Novem-
ber 21, 1694. His father was a prosperous notary, Francois Arouet,
the suffix "de Voltaire" being added when the poet and philosopher left
the Bastile. Voltaire's education was desultory until he was about ten
years old, when he was sent to the Jesuit College Louis-le-Grand.
After he left school in 1711 he was constrained by his father to
V 6—24
378 RELIGIOUS MOVEMENTS
take up the reading of law, but he never entered into it in more than a
half-hearted way, and gave most of his attention to literature.
His memberships in the coterie of the Duchess du Maine and cer-
tain lampoons ascribed to him against the regent Orleans cost him first
exile and then eleven months in the Bastile. It was on leaving that he
assumed the name by which he is commonly known. Soon afterwards
he became deservedly famous by his drama, the "CEdipe," and his heroic
poem, the "Henriade." This led him into close association with the
nobility. A sharp reply to an insult from the Chevalier de Rohan occa-
sioned his being beaten, and after being again confined in the Bastile,
sent off to England.
This English visit had an immense effect on his views and writings.
After his return to France he lived from 1734 to 1749 mostly with
Madame du Chatelet at her country house Cirey, in the independent
Duchy of Lorraine. All this time he was busy with his literary work.
The next three years were spent with Frederick of Prussia, and were
filled with quarrels characteristic both of Voltaire and Frederick. The
last of his life was spent as a country gentleman, first near Geneva, then
at Ferney. He died in 1778.
Voltaire was a great dramatist, but perhaps even a greater pam-
phleteer. His influence was constantly, but often secretly, lent against
intoleration in religion and state. In those days he was considered a
sceptic in religion and revolutionary in politics, but he was nevertheless
a Deist, and it is doubtful if his revolutionary tendencies extended as
far as merely the more liberal thought of today.
ON TOLERATION
WHETHER TOLERATION is DANGEROUS; AND AMONG WHAT NATIONS
IT is PRACTICED
Some people will have it that, if we were to make use of humanity
and indulgence towards our mistaken brethren who pray to God in bad
French, it would be putting arms in to their hands, and we should see
revived the bloody days of Jarnac, Moncontour, Coutras, Dreux, St.
Denis &c. I know not how this may be, as I have not the gift of
prophecy ; but I really cannot discover the congruity of this reasoning,
"that because these men took up arms against me when I oppressed
them, they will do the same if I show them favour."
RELIGIOUS MOVEMENTS 379
And here I would willingly take the liberty to entreat those who
have the reins of government in hand, or are destined to fill the highest
stations, for once to examine maturely, whether there is any reason to
apprehend that indulgence would occasion the same rebellions as cru-
elty and oppression; and whether, what has happened under certain
circumstances would happen under others of a different nature; or
whether times, opinions and manners are always the same ?
The Huguenots, it cannot be denied, have formerly been given into
all the rage of enthusiasm, and have been polluted with blood as well as
ourselves ; but can it be said that the present generation is as barbarous
as the former ? Have not time and reason, that have lately made so great
progress, together with good books, and that natural softness introduced
from society, found their way among those who have the guidance of
these people ? And do we not clearly perceive that almost all Europe has
undergone a change within the last century ?
The hands of government have everywhere been strengthened,
while the minds of the people have been softened and civilized ; the gen-
eral police, supported by numerous standing armies, leave us no longer
any cause to fear the return of those times of anarchy, when Protestant
boors and Catholic peasants were hastily called together from the labours
of agriculture to wield the sword against each other's lives.
Alia tempora, aliae curae. It would be highly absurd in the present
days to decimate the body of the Sorbonne because it formerly petitioned
for the burning the Pucelle d' Orleans; because it declared Henry III.
to have lost his right to the throne, and because it excommunicated and
proscribed the illustrious Henry IV. We should not certainly think of
prosecuting the other public bodies of the nation who committed the like
excesses in those times of error and madness ; it would not only be very
unjust, but as ridiculous as if we were to oblige all inhabitants of Mar-
seilles to undergo a course of physic, because they had the plague in
1720.
Should we at present go and sack Rome, as the troops of
Charles the Fifth did, because Pope Sixtus the Fifth, in the year 1585,
granted a nine years' indulgence to all Frenchmen who would take up
arms against their sovereign ? No, surely it is enough if we prevent the
court of Rome from ever being guilty of such excesses for the future.
The rage inspired by a spirit of controversy, and the abuse made of
the Christian religion from want of properly understanding it, has occa-
sioned as much bloodshed, and produced as many calamities in Germany,
380 RELIGIOUS MOVEMENTS
England and even in Holland, as in France ; and yet, at present the dif-
ference in religion occasions no disturbances in those countries ; but the
Jew, the Catholic, the Lutheran, the Calvinist, the Anabaptist, the Socin-
ian, the Moravian, and a multitude of other sects, live in brotherly
harmony together and contribute equally to the good of society.
In Holland they no longer fear that the disputations of a Gomar
concerning predestination should bring the head of a grand pensionary
to the block : nor in London, that the quarrels between the Presbyterians
and the Episcopalians about a form of prayer and a surplice, should
again spill the blood of their kings upon a scaffold. Ireland, now popu-
lous and rich, will not any more behold its Catholic inhabitants sacrific-
ing, as an acceptable offering, the lives of their Protestant brethren, by
burying them alive, hanging up mothers upon gibbets, and tying their
daughters around their neck to see them expire together; ripping up
women with child, taking the half-formed infants from the womb, and
throwing them to swine or dogs to be devoured ; putting a dagger into
the hands of their manacled prisoners and forcing them to plunge it into
the breasts of their fathers, their mothers, their wives or children,
thereby hoping to make them guilty of parricide, and damn their souls
while they destroyed their bodies : all of which we find related by Rapin,
who served as an officer in the English service in Ireland, and who lived
very near the time of those transactions, and confirmed by most of the
English historians. No ! such cruelties as they were never to be paral-
leled, so they doubtless will never be imitated. Philosophy, the sister of
religion, has herself snatched the poignard from the hands of supersti-
tion, so long bathed in blood ; and the human understanding, recovered
from its delirium, stands amazed at the shocking brutalities into which
it has been hurried by enthusiasm.
We ourselves know that in France there is a rich and populous
province, where the Protestant religion prevails much more than that of
the church of Rome. The University of Alsace consists almost entirely
of Lutherans, and they are likewise in possession of most of the civil
posts in that province ; and yet the public peace has never once been dis-
turbed by any quarrels about religion, since that province has belonged
to our kings. And what is the reason ? Because no one is persecuted
there on account of their religion. Seek not to lay a restraint upon the
mind, and you may always be sure that the mind will be yours.
I do not mean by this to insinuate that those who are of a different
faith to the prince under whose government they live, should have an
RELIGIOUS MOVEMENTS 381
equal share in the places of profits and honour with those who are of the
established religion of the state. In England the Roman Catholics, who
are in general looked upon to be friends to the Pretender, are excluded
from all civil employment and are even double taxed ; but then in every
other respect they enjoy the prerogatives of citizens.
Some of our bishops in France have been suspected of thinking that
their honour and interest is concerned, in not suffering any Protestants
within their diocese, and that this is the principal obstacle to allowing of
toleration amongst us ; but this I cannot believe. The Episcopal body in
France is composed of persons of quality, who think and act in a man-
ner suitable to their high birth ; and as envy itself must confess that they
are both generous and charitable, they therefore certainly cannot think
that those whom they thus drive out of their diocese would become con-
verts in any other country, but great honour would redound from the
conversion of them at home ; nor would the prelate be any loser by it in
his temporals, seeing that the greater the number of the inhabitants, the
greater is the value of the land.
A certain Polish bishop had a farmer, who was an Anabaptist, and a
receiver of his rents who was a Socinian. Some person proposed to the
bishop to prosecute the latter in the spiritual court for not believing in
transubstantiation, and to turn the other out of his farm because he
would not have his son christened till he was fifteen years of age; the
prelate very prudently replied, that though he made no doubt of their
being eternally damned in the next world, yet he found them extremely
necessary to him in this.
Let us now for a while quit our own little sphere and take a survey
of the rest of the globe. The grand seignior peaceably rules over sub-
jects of twenty different religions ; upwards of two hundred thousand
Greeks live unmolested within the walls of Constantinople; the mufti
himself nominates the Greek patriarch and presents him to the emperor ;
and at the same time allows of the residence of a Latin patriarch. The
sultan appoints Latin bishops for some of the Greek isles ; the form used
on this occasion is as follows : "I command such a one to go and reside
as bishop in the isle of Chios, according to the ancient custom and idle
ceremonies of those people." The Ottoman empire swarms with Jacob-
ines, Nestorians, Monothelites, Cophti, Christians of St. John, Guebres,
and Banians ; and the Turkish annals do not furnish us with one single
instance of a rebellion occasioned by any of these different sects.
Go into Indian, Persia, and Tartary, and you will meet with the
382 RELIGIOUS MOVEMENTS
same toleration and the same tranquility. Peter the Great encouraged
all kinds of religions throughout his vast empire : trade and agriculture
have been gainers by it, and no injury ever happened therefrom to the
body politic.
We do not find that the Chinese government, during the course of
four thousand years that it has subsisted, has ever adopted any other
religion than that of the Noachides, which consists in the simple wor-
ship of one God ; and yet it tolerates the superstitions of Fo, and that of
a multitude of bonzes ; which might be productive of dangerous conse-
quences did not the wisdom of the tribunals keep them within proper
bounds.
It is true that the great Yong-T-Chin, the most wise and magnani-
mous of all the emperors of China, drove the Jesuits out of his kingdom ;
but this was not because that prince himself was non-tolerant, but on the
contrary, because the Jesuits were so. They themselves, in their letters,
have given us the speech the emperor made to them on that occasion :
"I know, says he, that your religion admits not of toleration ; I know
how you have behaved in the Manilas and at Japan; you deceived
my father, but think not to deceive me in the same manner." And if we
read the whole of the conversation which he deigned to hold with them,
we must confess him to be the wisest and most clement of all princes.
How could he, indeed, with any consistency, keep in his kingdom Euro-
pean philosophers who, under the pretense of teaching the use of ther-
mometers and oeolypiles, had found means to debauch a prince of the
blood? But what would this emperor have said, had he read our his-
tories, and had he been acquainted with the times of the league and the
gunpowder plot ?
It was sufficient for him to be informed of the outrageous and in-
decent disputes between those Jesuits, Dominicans, Capuchins, and secu-
lar priests, who were sent as missionaries into his dominions from one
extremity of the globe to preach up truth; instead of which, they em-
ployed their time in mutually pronouncing damnation against each other.
The emperor, then, did no more than send away a set of foreigners, who
were disturbers of the public peace. But with what infinite goodness
did he dismiss them! and with what paternal care did he provide for
their accommodation in their journey, and to prevent their meeting with
any insult on their way ! This very act of banishment might serve as an
example of toleration and humanity.
The Japanese were the most tolerant of all nations ; twelve different
RELIGIOUS MOVEMENTS 383
religions were peacefully established in their empire : when the Jesuits
came, they made the thirteenth ; and, in a very little time after their ar-
rival, they would not suffer any other but their own. Every one knows
the consequences of these proceedings : a civil war, as calamitous as that
of the league, soon spread destruction and carnage through the empire ;
till at length the Christian religion was itself swallowed up in the tor-
rents of blood it had set a flowing, and the Japanese for ever shut the
entrance of their country against all foreigners, looking upon us as no
better than savage beasts, such as those from which the English have
happily cleared their island. Colbert, the minister, who knew the neces-
sity we were in of the commodities of Japan, that wants nothing from
us, laboured in vain to settle a trade with that empire ; he found those
people inflexible.
Thus then every thing on our Continent shows us, that we ought
neither to preach up, nor to exercise non-toleration.
Let us now cast our eyes on the other hemisphere. Behold Caro-
lina! whose laws were framed by the wise Locke; there every master
of a family, who has only seven souls under his roof, may establish what
religion he pleases, provided all those seven persons concur with him
therein ; and yet this great indulgence has not, hitherto, been the occa-
sion of any disorders. God forbid, that I should mention this as an
example to every master of a family to set up a particular worship in
his house : I have only introduced it to show that the utmost lengths to
which toleration can be carried, have never yet given rise even to the
slightest dissensions.
And what shall we say of those pacific primitive Christians, who
have, by way of derision, been called Quakers ; and who, though some
of their customs may perhaps be ridiculous, are yet remarkable for the
virtue and sobriety of their lives, and for having in vain endeavoured to
preach peace and good-will to the rest of mankind ? There are at least
an hundred thousand of them in Pennsylvania ; discord and controversy
are unknown in that happy spot where they have settled : the very name
of their principal city, Philadelphia, is a continual memento to them,
that all men are brethren, and is as once an example and reproach to
those nations who have not yet adopted toleration.
To conclude, toleration has never yet excited civil wars ; whereas
its opposite has filled the earth with slaughter and desolation. Let any
one then judge, which of the two is most entitled to our esteem, or which
we should applaud, the mother who would deliver her son into the hand
384 REUGIOUS MOVEMENTS
of the executioner, or she who would resign all right to him to save his
life.
In all what I have said, I have had only the interest of nations in
view and, as I pay all due respect to the doctrines of the church, I have
in this article, only considered the physical and moral advantages of so-
ciety. I therefore hope, that every impartial reader will properly weigh
these truths, that he will view them in their proper light, and rectify
what may be amiss. Those who read with attention, and reciprocally
communicate their thoughts, will always have the start of the author.
IN WHAT CASES TOLERATION MAY BE ADMITTED
Let me for once suppose, that a minister equally noble and discern-
ing, that a prelate equally wise and humane, or a prince who is sensible
that his interest consists in the increased number of his subjects, and his
glory in their happiness, may deign to cast their eyes on this random and
defective production. In this case, his own consummate knowledge will
naturally lead him to ask himself, what hazard shall I run by seeing the
land beautified and enriched by a greater number of industrious la-
bourers, the aids augmented, and the state rendered more flourishing ?
Germany, by this time, would have been a desert, covered with the
unburied bodies of many different sects, slaughtered by each other, had
not the peace of Westphalia happily procured a liberty of conscience.
We have Jews at Bordeaux, at Mentz, and in Alsace ; we have Lu-
therans, Molinists, and Jansenists amongst us; can we not then admit
protestants likewise under proper restrictions, nearly like those under
which the Roman catholics are permitted in England ? The greater the
number of different sects, the less danger is to be apprehended from any
one in particular; they become weaker in proportion as they are more
numerous, and are easily kept in subjection by those just laws which
prohibit riotous assemblies, mutual insults, and seditions, and which the
legislative power will always properly support in their full vigour.
We know that there are several heads of families, who have ac-
quired great fortunes in foreign countries, who would be glad to return
to their native country. These require only the protection of the law
of nature, to have their marriages to remain valid, and their children
secured in the enjoyment of their present property, and the right of suc-
ceeding to the inheritance of their fathers, together with a protection
for their persons. They ask no public places of worship ; they aim not
at the possession of civil employs, nor do they aspire to dignities either
RELIGIOUS MOVEMENTS 385
in church or state ; for no Roman catholics can enjoy any of these, either
in England or in any other protestant country. In this case, therefore,
there is no occasion for granting great privileges, or delivering strong-
holds into the hands of a faction, but only to suffer a quiet set of people
to breathe their native air ; to soften the rigour of some edicts, which in
former times might perhaps have been necessary, but at present are no
longer so. It is not for us to direct the ministry what it has to do ; it is
sufficient, if we presume to plead the cause of an unfortunate and dis-
tressed people.
Many and easy are the methods to render these people useful to the
state, and to prevent them from ever becoming dangerous : the wisdom
of the legislature, supported by the military force, will certainly find out
these methods, which other nations have employed with so much success.
It is certain, that there is still a number of enthusiasts among the
lower kind of Calvinists ; but, on the other hand, it is no less certain,
that there is still a greater number among the lower kind of bigotted
Roman catholics. The dregs of the madmen of St. Medard are passed
over unnoticed in the nation, while the greatest pains is taken to exter-
minate the Calvinist prophets. The most certain means to lessen the
number of the mad of both sorts, if any still remain, is to leave them
entirely to the care of reason, which will infallibly enlighten the under-
standing in the long run, though she may be slow in her operations.
Reason goes mildly to work, she persuades with humanity, she inspires
mutual indulgence and forbearance ; she stifles the voice of discord, es-
tablishes the rule of virtue and sobriety, and disposes those to pay a
ready obedience to the laws, who might start from the hand of power
when exerted to enforce them. Besides, are we to hold for nothing that
contempt and ridicule which enthusiasm every where meets with in the
present enlightened age, from persons of rank and education ? This very
contempt is the most powerful barrier that can be opposed to the extrav-
agancies of all sectaries. Past times are as though they never had been.
We should always direct our views from the point where we ourselves at
present are, and from that to which other nations have attained.
There has been a time, in which it was thought a duty to issue edicts
against all such who taught a doctrine contrary to the categories of
Aristotle, or who opposed the abhorrence of a vacuum, quiddities, or the
whole of the part of a thing. There are above an hundred volumes in
Europe, containing the writings of civilians against magic, and the
manner of distinguishing real sorcerers from pretended ones. The ex-
386 RELIGIOUS MOVEMENTS
communication of grasshoppers and other insects hurtful to the fruits
of the earth, was formerly much in use, and is still to be found in several
rituals ; that custom is now laid aside, and Aristotle, with his sorcerers
and the grasshoppers, are left to themselves. Innumerable are the ex-
amples of these grave follies, which formerly were deemed of great im-
portance ; others have succeeded from time to time, but as soon as they
have had their effect, and people begin to grow weary of them, they pass
away and are no more heard of. If any one was, at present, to take it
into his head to turn Eutichean, Nestorian, or Manichean, what would
be the consequence ? We should laugh at him in the same manner as at
a person who should appear dressed after the ancient fashion, with a
great ruff and slashed sleeves.
The first thing that opened the eyes of our nation was, when the
Jesuits Le Tellier and Doucin drew up the bull Unigenitus, and sent it
to the court of Rome, imagining they lived still in those times of ignor-
ance, in which people adopted, without examination, the most absurd
assertions. They even dared to proscribe a proposition, which is univer-
sally true in all cases and in all times, viz. "That the dread of an unjust
excommunication ought not to hinder any one from doing his duty."
This was, in fact, proscribing reason, the liberties of the Gallican church,
and the very foundation of all morality ; it was saying to mankind, "God
commands you never to do your duty, when you are apprehensive of suf-
fering any injustice. Never sure was so gross an insult offered to com-
mon sense, and yet this never occurred to these correspondents of the
church of Rome. Nay, they even persuaded that court that this bull was
necessary, that the nation desired it. Accordingly it was signed, sealed
and sent back to France ; and every one knows the consequences : assur-
edly, had they been foreseen, this bull would have been mitigated. Very
warm disputes ensued upon it ; but however, by the great prudence and
goodness of the king, they were at length appeased.
It is much the same with regard to most of those points, in which
the protestants and us at present differ; some of them are of little or
no consequence, others again are more serious ; but even in these latter,
the rage of disputation is so far subsided, that the protestants now-a-
days, no longer preach upon controversial points in any of their
churches.
Let us then seize this period of disgust or satiety for such matters,
or rather, indeed, of the prevalence of reason, as an epocha for restoring
the public tranquility, of which it seems to be a pleasing earnest. Con-
RELIGIOUS MOVEMENTS 387
troversy, that epidemical malady, is now in its decline, and requires noth-
ing more than a gentle regimen. In a word, it is the interest of the state,
that these wandering sects, who have so long lived as aliens to their fa-
ther's house, on their returning in a submissive and peaceable manner,
should meet with a favourable reception; humanity seems to demand
this, reason advises it, and good policy can have nothing to apprehend
from it.
IF NON-TOLERATION IS AGREEABLE TO THE LAW OF NATURE AND OF
SOCIETY
The law of nature is that which nature points out to all mankind.
You have brought up a child, that child owes you a respect as its parent,
and gratitude as its benefactor. You have a right over the productions
of the earth which you have raised by the labour of your own hands ;
you have given and received a promise, that promise ought to be kept.
The law of society can have no other foundation in any case than
on the law of nature. "Do not that to another which thou wouldst not
he should do unto thee," is the great and universal principle of both
throughout the earth : now, agreeable to this principle, can one man say
to another, "Believe that which I believe, and which thou thyself canst
not believe, or thou shalt die ?" And yet this is what is every day said in
Portugal, in Spain, and at Goa. In some other countries indeed, they
now content themselves with saying, "Believe as I do, or I will hold thee
in abhorrence ; believe like me, or I will do thee all the evil I can : wretch,
thou art not of my religion, and therefore thou hast no religion at all,
and oughtest to be held in execration by thy neighbours, thy city, and
thy province."
If the law of society directs such a conduct, the Japanese ought then
to hold the Chinese in detestation; the latter the Siamese, who should
persecute the inhabitants of the Ganges ; and they fall upon those of
India ; the Mogul should put to death the first Malabar he found in his
kingdom; the Malabar should poignard the Persian; the Persian mas-
sacre the Turk; and, altogether, should fall upon us Christians, who
have so many ages been cutting one another's throats.
The law of persecution then is equally absurd and barbarous ; it is
the law of tigers : nay, it is even still more savage for tigers destroy
only for the sake of food, whereas we have butchered one another on
account of a sentence or a paragraph.
388 RELIGIOUS MOVEMENTS
OF UNIVERSAL TOLERATION
It does not require any great art or studied elocution, to prove that
Christians ought to tolerate each other. Nay, I shall go still farther,
and say, that we ought to look upon all men as our brethren. How ! call
a Turk, a Jew, and a Siamese, my brother ? Yes, doubtless ; for are we
not all children of the same parent, and the creatures of the same
creator ?
But these people hold us in contempt, and call us idolaters ! Well
then, I should tell them that they were to blame. And I fancy that I
could stagger the headstrong pride of an Imian, or a Talapoin, was I to
address them in the following manner :
"This little globe, which is no more than a point, rolls together with
many other globes, in that immensity of space in which we are all alike
confounded. Man, who is an animal, about five feet high, is certainly a
very inconsiderable part of the creation ; but one of those hardly visible
beings, says to others of the same kind inhabiting another spot of the
globe, hearken to me, for the God of all these worlds has enlightened
me : there are about nine hundred millions of us little insects who inhabit
the earth, but my ant-hill is alone cherished by God, who holds all the
rest in horror and detestation ; those who live with me upon my spot will
alone be happy, and all the rest eternally wretched."
They would here stop me short and ask, What madman could have
made so ridiculous a speech ? I should then be obliged to answer them,
It is yourselves. After which I should endeavour to pacify them, but
perhaps that would not be very easy.
I might next address myself to the Christians and venture to say,
for example, to a Dominican, one of the judges of the inquisition,
"Brother, you know that every province in Italy has a jargon of its own,
and that they do not speak at Venice and Bergamo as they do at Flor-
ence. The academy de la Crusca has fixed the standard of the Italian
language; its dictionary is an unerring rule, and Buon Matei's gram-
mar is an infallible guide, from neither of which we ought to depart;
but do you think that the president of the academy, or in his absence
Buon Matei, could in conscience order the tongues of all the Venetians
and Bergamese, who persisted in their own country dialect, to be cut
out?"
The inquisitor would perhaps make me this reply : "There is a very
wide difference ; here the salvation of your soul is concerned ; and it is
RELIGIOUS MOVEMENTS 389
entirely for your good that the directory of the inquisition ordains that
you shall be seized, upon the deposition of a single person, though of the
most infamous character ; that you shall have no person to plead for you,
nor even be acquainted with the name of your accuser ; that the inquis-
itor shall promise you favour, and afterwards condemn you; that he
shall make you undergo five different kinds of torture, and that at length
you shall be either whipt, sent to the gallies, or burnt at the stake ; father
Ivouet, and the doctors Chaucalon, Zanchinus, Campegius, Royas, Fel-
inus, Gomarus, Diarbarus, and Gemelinus are exactly of this opinion,
consequently this pious practice will not admit of contradiction."
To all which I should take the liberty of making the following
reply : "Dear brother, you may perhaps be in the right, and I am per-
fectly well convinced of the great benefit you intend me ; but may I not
be saved without all this ?"
It is true that these horrible absurdities do not every day deform the
face of the earth ; but they have been very frequent, and one might easily
collect instances enough to make a volume much larger than that of the
holy gospels, which condemns such practices. It is not only very cruel
to persecute in this short life, those who do not think in the same manner
as we do, but I very much doubt if there is not an impious boldness in
pronouncing them eternally damned. In my opinion, it little befits such
insects of a summer's day, as we are, thus to anticipate the decrees of
Providence. I am very far from opposing that maxim of the church,
that "out of her pale there is no salvation :" on the contrary, I respect
that and every other part of her doctrine ; but, after all, can we be sup-
posed to be intimately acquainted with the ways of God, or to fathom the
whole depth of his mercy ? Is it not permitted us to hope in him, as well
as to fear him ? Is it not sufficient if we are faithful sons of the church,
without every individual presuming to wrest the power out of the hand
of God, and determine, before Him, the future destiny of our fellow
creatures ?
When we wear mourning for a king of England, Denmark, Swe-
den, or Prussia, do we say that we are in mourning for a damned soul
that is burning in hell ? There are about forty millions of inhabitants in
Europe who are not members of the church of Rome ; should we say to
every one of them, "Sir, as I look upon you to be infallibly damned, I
shall neither eat, drink, converse, nor have any connections with you ?"
Is there an ambassador of France, who when he is presented to the
Grand Seignior for an audience, will seriously say to himself, his sub-
390 RELIGIOUS MOVEMENTS
lime highness will infallibly burn to all eternity, for having submitted
to be circumcised ? If he really thought that the Grand Seignior was a
mortal enemy to God, and the object of divine vengeance, could he con-
verse with such a person ; nay indeed, ought he to be sent to him ? But
how could we carry on any commerce, or perform any of the civil duties
of society, if we were convinced that we were conversing with persons
destined to eternal damnation ?
O ye different worshippers of a God of mercy! if ye have cruel
hearts, if, while you adore that Deity who has placed the whole of his
law in these few words, "Love God and your neighbour," you have
loaded that pure and holy law with sophistical and unintelligible dis-
putes, if you have lighted the flames of discord sometimes for a new
word, and at others for a single letter only ; if you have annexed eternal
punishment to the omission of some few words, or of certain ceremonies,
which other people cannot comprehend, I must say to you with tears of
compassion for mankind : "Transport yourselves with me to that great
instant in which all men are to receive judgment from the hand of God,
who will then do unto every one according to their works, and with me
behold all the dead of past ages appearing in his presence. Are you very
sure that our heavenly father and creator will say to the wise and vir-
tuous Confucius, to the great legislator Solon, to Pythagoras, Zaleucus,
Socrates, Plato, the divine Antoninus, the good Trajan, to Titus the de-
light of human kind, and to many others who have been the models of
human kind : Depart from me, wretches ! into torments that know
neither alleviation nor end ; but are, like himself, everlasting. But you,
my well beloved servants, John Chatel, Ravaillac, Cartouche, Damiens,
&c. who have died according to the rules prescribed by the church, enter
thou into the joy of your Lord, and sit forever at my right-hand in
majesty and glory?"
Methinks I see you start with horror at these words ; however, as
they have escaped me, let them pass ; I shall say nothing more to you.
AN ADDRESS TO THE DEITY
No longer then do I address myself to men, but to thee, God of all
beings, of all worlds, and of all ages ; if it may be permitted weak crea-
tures, lost in immensity, and imperceptible to the rest of the universe, to
presume to petition thee for aught, who hast given plenty of all things,
and whose decrees are immutable as eternal. Deign to look with an eye
of pity upon the errors annexed to our natures ! let not these errors prove
the sources of misery to us ! Thou hast not given us hearts to hate, nor
RELIGIOUS MOVEMENTS 391
hands to kill each other ; grant then that we may mutually aid and assist
each other to support the burthen of this painful and transitory life!
May the trifling differences in the garments that cover our frail bodies,
in the mode of expressing our insignificant thoughts, in our ridiculous
customs, and our imperfect laws, in our idle opinions, and in our several
conditions and situations, that appear so disproportionate in our eyes,
and all are equal in thine ; in a word, may the slight variations that are
found amongst the atoms called men, not be made use of by us as signals
of mutual hatred and persecution ! May those who worship thee by the
light of tapers at noon-day, bear charitably with those who content them-
selves with the light of that glorious planet thou hast placed in the midst
of the heavens ! May those who dress themselves in a robe of white
linen to teach their hearers that thou art to be loved and feared, not de-
test or revile those who teach the same doctrine in long cloaks of black
wool ! May it be accounted the same to adore thee in a dialect formed
from an ancient or a modern language ! May those, who, clothed in
vestments of crimson or violet colour, rule over a little parcel of that
heap of dirt called the world, and are possessed of a few round frag-
ments of a certain metal, enjoy without pride or insolence what they call
grandeur and riches, and may others look on them without envy; for
thou knowest, O God, that there is nothing in all these vanities proper to
inspire envy or pride.
May all men remember that they are brethren ! may they alike abhor
that tyranny which seeks to subject the freedom of the will, as they do
the rapine which tears from the arms of industry the fruits of its peace-
ful labours ! And if the scourge of war is not to be avoided, let us not
mutually hate and destroy each other in the midst of peace ; but rather
make use of the few moments of our existence to join in praising, in a
thousand different languages, from one extremity of the world to the
other, thy goodness, O all merciful creator, to whom we are indebted
for that existence.
392
EIGHTEENTH CENTURY POLITICAL
ECONOMY
QUESNAY
IN OUR introduction to the political economy of the seventeenth
century earlier in this volume we trace, for the sake of historical unity,
a sufficient introduction to the political economy of the eighteenth cen-
tury also.
Frangois Quesnay was born at Merey, about twenty-eight miles
from Paris, June 4, 1694. His father was an advocate, who sacrificed
his business to his love for conciliating his neighbors. He learned some-
thing of the sciences, and some Greek and Latin without the aid of a
school or tutor. It is said that many times he walked to Paris for a
book. He studied medicine in Paris and in 1718 established a practice
at Mantes, his clients numbering such great persons as the Marechal de
Noailles and the queen. In 1730 he was made secretary of an academy
of surgery at Paris. Some fifteen years later he became physician to
Louis XV.
From this time he seems to have been especially interested in eco-
nomic studies. About 1750 he met M. de Gournay and the two men
became the center of what has become known as the physiocrat school.
The general idea of the school was to exalt the economic importance of
nature rather than legislation. Along this line they believed the pro-
duction of raw materials to be the only production of wealth, eulogized
agriculture, and wished freedom in trade. One of their great repre-
sentatives in politics was Turgot, whose reforms if carried out would
have done much to alleviate the French Revolution.
Quesnay died in 1774.
EIGHTEENTH CENTURY POLITICAL ECONOMY 393
GENERAL MAXIMS OF THE ECONOMICAL GOVERNMENT
IN AN AGRICULTURAL KINGDOM
MAXIM I. UNITY OF AUTHORITY
Let the sovereign authority be unrivalled and superior to all in-
dividuals of society, and to all unjust enterprises of particular interests ;
for the domination and subjection of certain forces is the safeguard
and lawful interest of all. The destructive theory of the system of
counterforces in a government can show nothing but discord between
the large proprietors and the lower class of farmers. The division of
society into different orders of citizens of which some exercise sover-
eign authority over others, destroys the general interest of the nation
itself and introduces the dissension of particular interests between the
different classes of people : this division would invest the order of the
government of an agricultural kingdom that would unite all interests,
having as the capital object, the prosperity of agriculture, which in itself
is the source of the state's and the people's riches.
II. Let the Nation be instructed as to General Natural Laws,
which make a Government more Perfect.
The study of human jurisprudence does not suffice to make states-
men ; it is necessary that they who are fitting themselves for public serv-
ice be constrained to the observance of natural law, which tends toward
the good of society as a whole. It is also necessary that the clear and
practical knowledge a nation acquires by experience and reflection be
added to the general science of government ; in order that the sovereign
authority, always surer in the light of experience, institutes the best
laws for the well-being of all to reach and embrace the greatest possible
prosperity for society.
III. Earth, Agriculture, Sole Source of Riches.
Let the sovereign and the nation never lose sight of the fact that
the earth is the sole source of all riches, and that it is agriculture which
multiplies riches.
For it is the augmentation of riches that assures the wealth of the
population ; men and wealth cause agriculture to prosper, extend com-
merce, animate industry, increase and perpetuate all wealth. Upon that
abundant source of wealth, agriculture, depends the success of all the
parties concerned in the administration of the kingdom.
G— 25
394 EIGHTEENTH CENTURY POLITICAL ECONOMY
IV. Let Landed Property and Movable Riches be assured to
Those who are the Legitimate Possessors of Them.
For the security of property is the substructure upon which the
economic order of society rests. Without the certainty of the security
and safety of property the land would remain untilled. There would be
neither proprietors nor tenants to make the necessary outlay in cultivat-
ing the land, if the title to the land and its products were not assured to
them who made the necessary outlay towards improvement and cultiva-
tion. It is the surety of permanent possession that brings about the em-
ploy of labor and riches in the improvement and culture of the land, and
in industrial and commercial enterprises. Nothing but a sovereign
power can assure the property of subjects who have a primitive right to
the portion of the fruits of the earth, the sole source of riches.
V. The Tax, — not to destroy.
Let taxes be not destructive nor disproportionate to the revenue of
the nation ; let increase in taxes attend increase in revenue ; let taxes be
immediately placed on the net product of property in land, and not on
the wages of man, nor on produce, where it would multiply the cost of
collection, would be prejudicial to commerce, and would annually de-
stroy a portion of the wealth of the nation. Neither should taxes be
placed on the riches of cultivators of landed property ; for investment in
the agriculture of a kingdom, i. e., advance money expended in agricul-
ture, must be regarded as a landed estate to be preciously preserved for
the raising of taxes and revenue and subsistence for all classes of citi-
zens. Otherwise the tax would degenerate to spoliation and promptly
cause the state to ruin and decay.
VI. Sufficient Investment.
Let the investment of cultivators be sufficient to cause annually to
re-appear from the expense undergone in cultivating the land the great-
est possible amount of production: for if the investment is not suffi-
cient the expense of culture is larger in proportion and gives less of net
product.
VII. Complete Circulation.
Let the sum total of the revenues be annually returned into and
along the entire course of circulation ; let no money fortunes be accu-
mulated, or rather, let there be compensation between those which are
made and those which are derived in the circulation ; for otherwise the
money fortunes would arrest the distribution of a portion of the annual
revenue of the nation and would withhold the moneys of the kingdom
EIGHTEENTH CENTURY POLITICAL ECONOMY 395
to the harm and prejudice of their re-investment into the cultivation of
the land, from paying the artisan's wages, from making the various pro-
fessions lucrative and would also diminish the reproduction of revenues
and taxes.
VIII. Favor for Productive Expenditures.
Let the economic government favor productive expenditures and
the commerce of the land's products and let fruitless expenditure attend
to itself.
IX. Preference for Agriculture.
Let a nation which has a large territory to cultivate and the facili-
ties to carry on a large commerce with the land's products not use too
much of the people's money in the manufactures and in the commerce
of luxuries to the prejudice of labor and agricultural investments ; for
above all, the kingdom would well be a people of rich agriculturists.
X. Revenue Expended in the Country.
Let none of the revenue pass into the home of the stranger without
return either in money or merchandise.
XL Evils of Emigration.
Let the desertion of those inhabitants who would take with them
their wealth, to the loss of the kingdom, be prevented.
XII. Protection of the Person and the Wealth of Agriculturists.
Let the children of rich farmers establish themselves in the country
so as to perpetuate and preserve husbandry ; for if vexation of any kind
causes them to abandon the country and determines them to repair into
the cities they take with them the wealth of their fathers who were em-
ployed in agriculture. It is less men than wealth that should be drawn
into the country, for the more one employs money in agriculture the less
it occupies men and prospers more and gives more to the revenue. Take,
for example, grain, the great product of the rich agriculturist, and com-
pare that with the contracted tillage of a poor tenant who labors with
an axe or a cow.
XIII. Freedom of Cultivation.
Let each one be free to cultivate in his own field those products that
his interest, his faculties, and the nature of the earth suggest to him will
produce the largest possible result. One ought not to favor monopoly in
the cultivation of land, for it is prejudicial to the general revenue of the
nation. The precedent that favors the abundance of products of the
greatest need, in preference to other productions, disregarding the pur-
chasable value of the one or the other, is inspired by that short-sighted-
396 EIGHTEENTH CENTURY POLITICAL ECONOMY
ness that sees not the effects of exterior reciprocal commerce that sup-
plies to all; and which fixes the price of the products that each nation
can cultivate with the greatest profit. Next to the riches of land culti-
vation, it is the revenue and taxes that are the riches most needed in a
state to defend subjects against scarcity of food and want, against ene-
mies, and to sustain the glory and strength of the monarch and the
prosperity of the nation.
XIV. Multiplication of Cattle.
Let the raising and multiplication of cattle be favored ; for it is they
that furnish to the earth the manure that produces the richest harvests.
XV. Cultivation Extensive Enough.
Let the land employed in the culture of grain be reunited as far as
possible to form large farms to be cultivated by rich laborers ; for there
is less of expense and much more of net products in the larger enter-
prises of agriculture than in the smaller. The multiplicity of small
farmers is prejudicial to the population. A more secure population, more
freedom for the different occupations, and different labors that divide
men into different classes, it is this that is maintained by the net product.
All thrift and economy profits the work that can be done by means of
animals, machinery, rivers, etc., returns to the advantage of the people
and the state, for the greater the net product, the more of gain is there to
the people of whatever service or occupation.
XVI. No Obstacle to the Exportation of Goods.
External commerce of the products of the land should not be ar-
rested nor prevented in any way, for it is the demand, the market, that
regulates the production each year.
XVII. Freedom and Ease in Transportation.
Let the means of the transportation of the productions of manual
labor be facilitated by repairing roadways, and by the navigation of
canals, of rivers, and of the sea ; for the more that is saved in the act of
carrying on commerce, so much more is added to the revenue of the
territory.
XVIII. Good Prices for Agricultural Products and Merchandise.
Let the price of agricultural products and merchandise, in a coun-
try, be not lowered ; for then reciprocal commerce with foreign countries
would become disadvantageous to the nation. As is the purchasable
value of things, so is the revenue. Abundance and no value is not
wealth. Dearth and high prices is misery. Abundance and high prices
is opulence.
XIX. Low Prices Are Harmful to the People.
EIGHTEENTH CENTURY POLITICAL ECONOMY 397
Low prices are not profitable to the laboring class ; for cheapness of
products lowers the wages of the laboring people, diminishes their com-
fort, procures less lucrative work and occupation for them, and destroys
the revenue of the nation.
XX. Comfort for the Lowest Classes of Citizens.
Let the comfort of the lowest classes of citizens be not diminished ;
for they must aid in the consumption of products, if reproduction and
the revenue of the nation are not to be lessened.
XXI. Avoid Unfruitful Economy.
Let the landlords and those who exercise the lucrative professions
not give themselves up to unfruitful economy, for this would cut off
from circulation and distribution a portion of their revenue or of their
gains.
XXII. Little or None of the Luxury of Decoration.
Let the luxury of decoration not be entertained to the detriment of
land culture, or any of the investments and outlays made necessary for
subsistence, for the stability of these preserves good prices, the demand
for the lands, products, and the production of the nation's revenue.
XXIII. Reciprocity in Commerce.
Let the nation not suffer from loss through reciprocal commerce
with other countries even if this commerce were profitable to the mer-
chants, who would gain, regardless of the welfare of fellow-citizens, in
the sale of commodities thus brought about. The accumulations of the
fortunes of these merchants would create a curtailment in the circula-
tion of revenue prejudicial to distribution and reproduction.
XXIV. Balance of Money in Trade is Illusory.
Let no one be deceived by an apparent advantage in reciprocal com-
merce with foreign countries, which is simply a balance received in
money, without examining and comparing the profits that result from
the merchandise one has sold and the merchandise which has been
bought. For often the loss is to that nation which receives a surplus in
money. And that loss reacts to the prejudice of the distribution and
reproduction of the revenues.
XXV. Complete Liberty in Commerce.
Let there be complete liberty in commerce; for the surest, most
exact, and most profitable policy for interior and exterior commerce of
the state and nation consists in the greatest possible freedom in compe-
tition.
XXVI. Attention to the Revenue Rather Than to Population.
398 EIGHTEENTH CENTURY POLITICAL ECONOMY
Let there be less attention given to the augmentation of the popula-
tion than to the accumulation of revenue, for greater freedom or ease in
procuring large revenues is preferable to the greater pressing wants of
subsistence, created by a population, and which exceed the revenue ; and
the resources are greater for the needs of a state when a people are In
comfort, and there are also more means to make agriculture prosperous.
XXVII. No Economization of the Necessary Public Expendi-
tures.
Let the government occupy itself with those operations necessary
for the prosperity of the kingdom rather than with attention toward
expenditures ; for with greater riches the larger expenses will cease to
appear so excessive. But one should not confound a perversion of funds
with simple expenses, for such a perversion can dissipate all the riches
of a nation and of the sovereign.
XXVIII. No Pecuniary Fortunes in the Administration of Taxes.
Let the administration of the finances be in the tax collection, not in
the expenses of the government, nor occasion pecuniary fortunes that
take away a portion of the revenue from circulation, distribution and
reproduction.
XXIX. Credit of Financiers, Harmful Resource.
Let no one hope for resources, to meet the extraordinary needs of a
state, but in the prosperity of the nation, and not in the credit of finan-
ciers ; for pecuniary fortunes are clandestine riches that know not king
nor country.
XXX. Borrowing Always Injurious.
Let the state avoid loans formed of the funds of financiers, for they
burden a state with devouring debts, occasion a commerce or traffic of
the finances, through the agency of negotiable paper, and where the
rebate or discount augments more and more the unfruitful pecuniary
fortunes. These fortunes separate money from agriculture and
deprive the country of the necessary riches for the improvement of real
estate and the exploitation of agriculture.
TRANSLATED BY E. R. BLAKE.
399
ADAM SMITH
ADAM SMITH was born June 5, 1723, in Fifeshire, Scotland, a few
months after the death of his father. In 1737 he began attending the
University of Glasgow, and in 1740 changed to Oxford. In 1748 he
gave lectures on literature in Edinburgh, and about this time became a
friend of David Hume. In 1751 he was made professor of logic at
Glasgow and later professor of moral philosophy.
In 1763 he took charge of the young Duke of Buccleuch on his trav-
els, and remained abroad for three years. For the next ten years he
lived with his mother at Kirkcaldy, happy and contented, and busy with
his Wealth of Nations. This was published in 1776.
In 1778 he was made a commissioner of customs at Edinburgh, and
in 1787 Lord Rector of Glasgow University. He died in 1790.
The Wealth of Nations is in some respects a compromise between
the mercantile and physiocrat theories, but its ideas are much fur-
ther wrought out. Smith considered the nation but the sum of the indi-
viduals in it, and wealth to be due to both labor and natural resources.
He buried the restrictive theory of trade for many years, but believed in
such public interference as compulsory education, public fortifications
and improvements and the like. He made a minute analysis of the fac-
tors of economics, such as the division of labor, exchange, value, price,
wages, profits, rent, capital and wealth, taxes, etc., and placed the whole
subject on a scientific basis.
The direct political outgrowth of his ideas was free trade in Eng-
land and non-intervention in her colonies.
OF THE PRINCIPLE OF THE COMMERCIAL OR
MERCANTILE SYSTEM
That wealth consists in money, or in gold and silver, is a popular
notion which naturally arises from the double function of money, as the
instrument of commerce, and as the measure of value. In consequence
400 EIGHTEENTH CENTURY POLITICAL ECONOMY
of its being the instrument of commerce, when we have money we can
more readily obtain whatever else we have occasion for, than by means
of any other commodity. The great affair, we always find, is to get
money. When that is obtained, there is no difficulty in making any sub-
sequent purchase. In consequence of its being the measure of value, we
estimate that of all other commodities by the quantity of money which
they will exchange for. We say of a rich man that he worth a great
deal, and of a poor man that he is worth very little money. A frugal man,
or a man eager to be rich, is said to love money ; and a careless, a gener-
ous or a profuse man, is said to be indifferent about it. To grow rich is
to get money ; and wealth and money, in short, are in common language
considered as in every respect synonymous.
A rich country, in the same manner as a rich man, is supposed to be
a country abounding in money ; and to heap up gold and silver in any
country is supposed to be the readiest way to enrich it. For some time
after the discovery of America, the first inquiry of the Spaniards, when
they arrived upon any unknown coast, used to be, if there was any gold
or silver to be found in the neighbourhood ? By the information which
they received, they judged whether it was worth while to make a settle-
ment there, or if the country was worth the conquering. Piano Carpino,
a monk sent ambassador from the king of France to one of the sons of
the famous Gengis Khan, says that the Tartars used frequently to ask
him if there were plenty of sheep and oxen in the kingdom of France.
Their inquiry had the same object with that of the Spaniards. They
wanted to know if the country was rich enough to be worth the con-
quering. Among the Tartars, as among all other nations of shepherds,
who are generally ignorant of the use of money, cattle are the instru-
ments of commerce and the measures of value. Wealth, therefore,
according to them, consisted in cattle, as according to the Spaniards it
consisted in gold and silver. Of the two, the Tartar notion perhaps was
the nearest to the truth.
Mr. Locke remarks a distinction between money and other mov-
able goods. All other movable goods, he says, are of so consumable a
nature that the wealth which consists in them cannot be much depended
on, and a nation which abounds in them one year may, without any
exportation, but merely by their own waste and extravagance, be in
great want of them the next. Money, on the contrary, is a steady friend,
which, though it may travel about from hand to hand, yet if it can be
kept from going out of the country, is not very liable to be wasted and
EIGHTEENTH CENTURY POLITICAL ECONOMY 401
consumed. Gold and silver, therefore, are, according to him, the most
solid and substantial part of the movable wealth of a nation, and to mul-
tiply those metals ought, he thinks, upon that account, to be the great
object of its political economy.
Others admit that if a nation could be separated from all the world,
it would be of no consequence how much or how little money circulated
in it. The consumable goods which were circulated by means of money,
would only be exchanged for a greater or a smaller number of pieces ;
but the real wealth or poverty of a country, they allow, would depend al-
together upon the abundance or scarcity of those consumable goods. But
it is otherwise, they think, with countries which have connections with
foreign nations, and which are obliged to carry on foreign wars, and to
maintain fleets and armies in distant countries. This, they say, cannot
be done but by sending abroad money to pay them with ; and a nation
cannot send much money abroad, unless it has a good deal at home.
Every such nation, therefore, must endeavour in time of peace to accum-
ulate gold and silver, that, when occasion requires, it may have where-
withal to carry on foreign wars.
In consequence of these popular notions, all the different nations of
Europe have studied, though to little purpose, every possible means of
accumulating gold and silver in their respective countries. Spain and
Portugal, the proprietors of the principal mines which supply Europe
with those metals, have either prohibited their exportation under the
severest penalties, or subjected it to a considerable duty. The like pro-
hibition seems anciently to have made a part of the policy of most other
European nations. It is even to be found, where we should least of all
expect to find it, in some old Scotch Acts of Parliament, which forbid
under heavy penalties the carrying gold or silver forth of the kingdom.
The like policy anciently took place both in France and England.
When those countries became commercial, the merchants found this
prohibition, upon many occasions, extremely inconvenient. They could
frequently buy more advantageously with gold and silver than with any
other commodity, the foreign goods which they wanted, either to import
into their own, or to carry to some other foreign country. They remon-
strated, therefore, against this prohibition as hurtful to trade.
They represented, first, that the exportation of gold and silver in
order to purchase foreign goods, did not always diminish the quantity of
those metals in the kingdom. That, on the contrary, it might frequently
increase that quantity ; because, if the consumption of foreign goods was
402 EIGHTEENTH CENTURY POLITICAL ECONOMY
not thereby increased in the country, those goods might be re-exported
to foreign countries, and being there sold for a large profit, might bring
back much more treasure than was originally sent out to purchase them.
Mr. Mun compares this operation of foreign trade to the seed-time and
harvest of agriculture. "If we only behold," says he, "the actions of the
husbandman in the seed-time, when he casteth away much good corn
into the ground, we shall account him rather a madman than a husband-
man. But when we consider his labours in the harvest, which is the end
of his endeavours, we shall find the worth and plentiful increase of his
actions."
They represented, secondly, that this prohibition could not hinder
the exportation of gold and silver, which, on account of the smallness of
their bulk in proportion to their value, could easily be smuggled abroad.
That this exportation could only be prevented by a proper attention to
what they called the balance of trade. That when the country exported
to a greater value than it imported, a balance became due to it from for-
eign nations, which was necessarily paid to it in gold and silver, and
thereby increased the quantity of those metals in the kingdom. But that
when it imported to a greater value than it exported, a contrary balance
became due to foreign nations, which was necessarily paid to them in the
same manner, and thereby diminished that quantity. That in this case
to prohibit the exportation of those metals could not prevent it, but only,
by making it more dangerous, render it more expensive. That the ex-
change was thereby turned more against the country which owed the bal-
ance than it otherwise might have been ; the merchant who purchased a
bill upon a foreign country being obliged to pay the banker who sold it,
not only for the natural risk, trouble, and expense of sending the money
thither, but for the extraordinary risk arising from the prohibition. But
that the more the exchange was against any country, the more the bal-
ance of trade became necessarily against it ; the money of that country
becoming necessarily of so much less value, in comparison with that of
the country to which the balance was due. That if the exchange between
England and Holland, for instance, was five per cent against England,
it would require a hundred and five ounces of silver in England to pur-
chase a bill for a hundred ounces of silver in Holland : that a hundred
and five ounces of silver in England, therefore, would be worth only a
hundred ounces of silver in Holland, and would purchase only a propor-
tionable quantity of Dutch goods ; but that a hundred ounces of silver in
Holland, on the contrary, would be worth a hundred and five ounces in
EIGHTEENTH CENTURY POLITICAL ECONOMY 403
England, and would purchase a proportionable quantity of English
goods : that the English goods which were sold to Holland would be sold
so much cheaper ; and the Dutch goods which were sold to England, so
much dearer, by the difference of the exchange ; that the one would
draw so much less Dutch money to England, and the other so much more
English money to Holland, as this difference amounted to : and that the
balance of trade, therefore, would necessarily be so much more against
England, and would require a greater balance of gold and silver to be
exported to Holland.
Those arguments were partly solid and partly sophistical. They
were solid so far as they asserted that the exportation of gold and silver
in trade might frequently be advantageous to the country. They were
solid, too, in asserting that no prohibition could prevent their exporta-
tion, when private people found any advantage in exporting them. But
they were sophistical in supposing that, either to preserve or to augment
the quantity of those metals required more the attention of government,
than to preserve or to augment the quantity of any other useful commod-
ities, which the freedom of trade, without any such attention, never fails
to supply in the proper quantity. They were sophistical, too, perhaps, in
asserting that the high price of exchange necessarily increased what they
called the unfavourable balance of trade, or occasioned the exportation
of a greater quantity of gold and silver. That high price, indeed, was ex-
tremely disadvantageous to the merchants who had any money to pay in
foreign countries. They paid so much dearer for the bills which their
bankers granted them upon those countries. But though the risk arising
from the prohibition might occasion some extraordinary expense to the
bankers, it would not necessarily carry any more money out of the coun-
try. This expense would generally be all laid out in the country, in
smuggling the money out of it, and could seldom occasion the exporta-
tion of a single sixpence beyond the precise sum drawn for. The high
price of exchange, too, would naturally dispose the merchants to en-
deavour to make their exports nearly balance their imports, in order that
they might have this high exchange to pay upon as small a sum as pos-
sible. The high price of exchange, besides, must necessarily have oper-
ated as a tax in raising the price of foreign goods, and thereby dimin-
ishing their consumption. It would tend, therefore, not to increase, but
to diminish what they called the unfavourable balance of trade, and con-
sequently the exportation of gold and silver.
Such as they were, however, those arguments convinced the people
404 EIGHTEENTH CENTURY POLITICAL ECONOMY
to whom they were addressed. They were addressed by merchants to
parliaments, and to the councils of princes, to nobles and to country gen-
tlemen ; by those who were supposed to understand trade, to those who
were conscious to themselves that they knew nothing about the matter.
That foreign trade enriched the country, experience demonstrated to the
nobles and country gentlemen, as well as to the merchants ; but how, or
in what manner, none of them well knew. The merchants knew per-
fectly in what manner it enriched themselves. It was their business to
know it. But to know in what manner it enriched the country, was no
part of their business. The subject never came into their consideration
but when they had occasion to apply to their country for some change in
the laws relating to foreign trade. It then became necessary to say some-
thing about the beneficial effects of foreign trade, and the manner in
which those effects were obstructed by the laws as they then stood. To
the judges who were to decide the business, it appeared a most satisfac-
tory account of the matter, when they were told that foreign trade
brought money into the country, but that the laws in question hindered
it from bringing so much as it otherwise would do. Those arguments
therefore produced the wished-for effect. The prohibition of exporting
gold and silver was in France and England confined to the coin of those
respective countries. The exportation of foreign coin and of bullion was
made free. In Holland, and in some other places, this liberty was ex-
tended even to the coin of the country. The attention of government
was turned away from guarding against the exportation of gold and
silver, to watch over the balance of trade, as the only cause which could
occasion any augmentation or diminution of those metals. From one
fruitless care it was turned away to another care much more intricate,
much more embarrassing, and just equally fruitless. The title of Mun's
book, England's Treasure in Foreign Trade, became a fundamental
maxim in the political economy, not of England only, but of all other
commercial countries. The inland or home trade, the most important of
all, the trade in which an equal capital affords the greatest revenue, and
creates the greatest employment to the people of the country, was consid-
ered as subsidiary only to foreign trade. It neither brought money into
the country, it was said, nor carried any out of it. The country, therefore,
could never become either richer or poorer by means of it, except so far
as its prosperity or decay might indirectly influence the state of foreign
trade.
A country that has no mines of its own must undoubtedly draw its
EIGHTEENTH CENTURY POLITICAL ECONOMY 405
gold and silver from foreign countries, in the same manner as one that
has no vineyards of its own must draw its wines. It does not seem neces-
sary, however, that the attention of government should be more turned
towards the one than towards the other object. A country that has
wherewithal to buy wine, will always get the wine which it has occasion
for; and a country that has wherewithal to buy gold and silver, will
never be in want of those metals. They are to be bought for a certain
price like all other commodities, and as they are the price of all other
commodities, so all other commodities are the price of those metals. We
trust with perfect security that the freedom of trade, without any atten-
tion of government, will always supply us with the wine which we have
occasion for ; and we may trust with equal security that it will always
supply us with all the gold and silver which we can afford to purchase or
to employ, either in circulating our commodities, or in other uses.
The quantity of every commodity which human industry can either
purchase or produce, naturally regulates itself in every country accord-
ing to the effectual demand, or according to the demand of those who
are willing to pay the whole rent, labour, and profits which must be paid
in order to prepare and bring it to market. But no commodities regulate
themselves more easily or more exactly according to this effectual
demand than gold and silver ; because, on account of the small bulk and
great value of those metals, no commodities can be more easily trans-
ported from one place to another, from the places where they are cheap
to those where they are dear; from the places where they exceed, to
those where they fall short of this effectual demand. If there was in Eng-
land, for example, an effectual demand for an additional quantity of
gold, a packet-boat could bring from Lisbon, or wherever else it was to
be had, fifty tons of gold, which could be coined into more than five
millions of guineas. But if there was an effectual demand for grain to
the same value, to import it would require, at five guineas a ton, a million
tons of shipping, or a thousand ships of a thousand tons each. The navy
of England would not be sufficient.
When the quantity of gold and silver imported into any country
exceeds the effectual demand, no vigilance of government can prevent
their exportation. All the sanguinary laws of Spain and Portugal are
not able to keep their gold and silver at home. The continual importa-
tions from Peru and Brazil exceed the effectual demand of those
countries, and sink the price of those metals there below that in the
neighbouring countries. If, on the contrary, in any particular country
406 EIGHTEENTH CENTURY POLITICAL ECONOMY
their quantity fell short of the effectual demand, so as to raise their price
above that of the neighbouring countries, the government would have no
occasion to take any pains to import them. If it was even to take pains
to prevent their importation, it would not be able to effectuate it. Those
metals, when the Spartans had the wherewithal to purchase them, broke
through all the barriers which the laws of Lycurgus opposed to their
entrance into Lacedemon. All the sanguinary laws of the customs are
not able to prevent the importation of the teas of the Dutch and Gotten-
burg East India companies, because somewhat cheaper than those of the
British company. A pound of tea, however, is about a hundred times
the bulk of one of the highest prices, sixteen shillings, that is commonly
paid for it in silver, and more than two thousand times the bulk of the
same price in gold, and consequently just so many times more difficult
to smuggle.
It is partly owing to the easy transportation of gold and silver from
the places where they abound to those where they are wanted, that the
price of those metals does not fluctuate continually like that of the
greater part of other commodities, which are hindered by their bulk
from shifting their situation, when the market happens to be either over
or understocked with them. The price of those metals, indeed, is not
altogether exempted from variation, but the changes to which it is liable
are generally slow, gradual and uniform. In Europe, for example, it is
supposed, without much foundation perhaps, that, during the course of
the present and preceding century, they have been constantly, but grad-
ually sinking in their value, on account of the continual importations
from the Spanish West Indies. But to make any sudden change in the
price of gold and silver, so as to raise or lower at once, sensibly and
remarkably, the money price of all other commodities, requires such a
revolution in commerce as that occasioned by the discovery of America.
If, notwithstanding all this, gold and silver should at any time fall
short in a country which has wherewithal to purchase them, there are
more expedients for supplying their place than that of almost any other
commodity. If the materials of manufacture are wanted, industry must
stop. If provisions are wanted, the people must starve. But if money is
wanted, barter will supply its place, though with a good deal of incon-
veniency. Buying and selling upon credit, and the different dealers com-
pensating their credits with one another, once a month or once a year,
will supply it with less inconveniency. A well-regulated paper money
will supply it, not only without inconveniency, but in some cases with
EIGHTEENTH CENTURY POLITICAL ECONOMY 407
some advantages. Upon every account, therefore, the attention of gov-
ernment never was so unnecessarily employed as when directed to watch
over the preservation or increase of the quantity of money in any
country.
No complaint, however, is more common than that of a scarcity of
money. Money, like wine, must always be scarce with those who have
neither wherewithal to buy it, nor credit to borrow it. Those who have
either, will seldom be in want either of the money or of the wine which
they have occasion for. This complaint, however, of the scarcity of
money, is not always confined to improvident spendthrifts. It is some-
times general through a whole mercantile town, and the country in its
neighbourhood. Overtrading is the common cause of it. Sober men,
whose projects have been disproportioned to their capitals, are as likely
to have neither wherewithal to buy money, nor credit to borrow it, as
prodigals whose expense has been disproportioned to their revenue.
Before their projects can be brought to bear, their stock is gone, and
their credit with it. They run about everywhere to borrow money, and
everybody tells them that they have none to lend. Even such general
complaints of the scarcity of money do not always prove that the usual
number of gold and silver pieces are not circulating in the country, but
that many people want those pieces who have nothing to give for them.
When the profits of trade happen to be greater than ordinary, over-
trading becomes a general error both among great and small dealers.
They do not always send more money abroad than usual, but they buy
upon credit both at home and abroad, an unusual quantity of goods,
which they send to some distant market, in hopes that the returns will
come in before the demand for payment. The demand comes be-
fore the returns, and they have nothing at hand with which
they can either purchase money, or give solid security for borrowing. It
is not any scarcity of gold and silver, but the difficulty which such people
find in borrowing, and which their creditors find in getting payment, that
occasions the general complaint of the scarcity of money.
It would be too ridiculous to go about seriously to prove that wealth
does not consist in money, or in gold and silver, but in what money pur-
chases, and is valuable only for purchasing. Money, no doubt, makes
always a part of the national capital ; but it has already been shown that
it generally makes but a small part, and always the most unprofitable
part of it.
I thought it necessary, though at the hazard of being tedious, to
408 EIGHTEENTH CENTURY POLITICAL ECONOMY
examine at full length this popular notion, that wealth consists in money,
or in gold and silver. Money in common language, as I have already
observed, frequently signifies wealth ; and this ambiguity of expression
has rendered this popular notion so familiar to us that even they who
are convinced of its absurdity are very apt to forget their own principles,
and in the course of their reasonings to take it for granted as a certain
and undeniable truth. Some of the best English writers upon commerce
set out with observing that the wealth of a country consists, not in its
gold and silver only, but in its lands, houses, and consumable goods of
all kinds. In the course of their reasonings, however, the lands, houses,
and consumable goods seem to slip out of their memory, and the strain
of their argument frequently supposes that all wealth consists in gold
and silver, and that to multiply those metals is the great object of
national industry and commerce.
The two principles being established, however, that wealth con-
sisted in gold and silver, and that those metals could be brought into a
country which had no mines only by the balance of trade, or by exporting
to a greater value than it imported, it necessarily became the great object
of political economy to diminish as much as possible the importation of
foreign goods for home consumption, and to increase as much as pos-
sible the exportation of the produce of domestic industry. Its two great
engines for enriching the country, therefore, were restraints upon im-
portation and encouragements to exportation.
The restraints upon importation were of two kinds :
First, restraints upon the importation of such foreign goods for
home consumption as could be produced at home, from whatever coun-
try they were imported.
Secondly, restraints upon the importation of goods of almost all
kinds from those particular countries with which the balance of trade
was supposed to be disadvantageous.
Those different restraints consisted sometimes in high duties and
sometimes in absolute prohibitions.
Exportation was encouraged sometimes by drawbacks, sometimes
by bounties, sometimes by advantageous treaties of commerce with sov-
ereign states, and sometimes by the establishment of colonies in distant
countries.
Drawbacks were given upon two different occasions. When the
home manufactures were subject to any duty or excise, either the whole
or a part of it was frequently drawn back upon their exportation ; and
EIGHTEENTH CENTURY POLITICAL ECONOMY 403
when foreign goods liable to a duty were imported in order to be ex-
ported again, either the whole or a part of this duty was sometimes given
back upon such exportations.
Bounties were given for the encouragement either of some begin-
ning manufactures, or of such sorts of industry of other kinds as were
supposed to deserve particular favour.
By advantageous treaties of commerce, particular privileges were
procured in some foreign state for the goods and merchants of the coun-
try, beyond what were granted to those of other countries.
By the establishment of colonies in distant countries, not only par-
ticular privileges but a monopoly was frequently procured for the goods
and merchants of the country which established them.
The two sorts of restraints upon importation above mentioned,
together with those four encouragements to exportation, constitute the
six principal means by which the commercial system proposes to increase
the quantity of gold and silver in any country by turning the balance of
trade in its favour. I shall consider each of them in a particular chap-
ter, and, without taking much further notice of their supposed tendency
to bring money into the country, I shall examine chiefly what are likely
to be the effects of each of them upon the annual produce of its industry.
According as they tend either to increase or diminish the value of this
annual produce, they must evidently tend either to increase or diminish
the real wealth and revenue of the country.
OF RESTRAINTS UPON THE IMPORTATION FROM FOR-
EIGN COUNTRIES OF SUCH GOODS AS CAN
BE PRODUCED AT HOME
By restraining, either by high duties, or by absolute prohibitions,
the importation of such goods from foreign countries as can be pro-
duced at home, the monopoly of the home market is more or less secured
to the domestic industry employed in producing them. Thus the prohi-
bition of importing either live cattle or salt provisions from foreign
countries secures to the graziers of Great Britain the monopoly of the
home market for butchers' meat. The high duties upon the importation
of corn, which in times of moderate plenty amount to a prohibition, give
a like advantage to the growers of that commodity. The prohibition of
the importation of foreign woolens is equally favourable to the woolen
V 6-26
410 EIGHTEENTH CENTURY POLITICAL ECONOMY
manufacturers. The silk manufacture, though altogether employed
upon foreign materials, has lately obtained the same advantage. The
linen manufacture has not yet obtained it, but is making great strides
towards it. Many other sorts of manufacturers have, in the same
manner, obtained in Great Britain, either altogether, or very nearly a
monopoly against their countrymen. The variety of goods of which the
importation into Great Britain is prohibited, either absolutely or under
certain circumstances, greatly exceeds what can easily be suspected by
those who are not well acquainted with the laws of the customs.
That this monopoly of the home market frequently gives great
encouragement to that particular species of industry which enjoys it, and
frequently turns towards that employment a greater share of both the
labour and stock of the society than would otherwise have gone to it,
cannot be doubted. But whether it tends either to increase the general
industry of the society, or to give it the most advantageous direction, is
not, perhaps, altogether so evident.
The general industry of the society can never exceed what the cap-
ital of the society can employ. As the number of workmen that can be
kept in employment by any particular person must bear a certain propor-
tion to his capital, so the number of those that can be continually em-
ployed by all the members of a great society, must bear a certain
proportion to the whole capital of that society, and never can exceed that
proportion. No regulation of commerce can increase the quantity of
industry in any society beyond what its capital can maintain. It can only
divert a part of it into a direction into which it might not otherwise have
gone ; and it is by no means certain that this artificial direction is likely
to be more advantageous to the society than that into which it would
have gone of its own accord.
Every individual is continually exerting himself to find out the most
advantageous employment for whatever capital he can demand. It is his
own advantage, indeed, and not that of the society, which he has in view.
But the study of his own advantage naturally, or rather necessarily,
leads him to prefer that employment which is most advantageous to the
society.
First, every individual endeavours to employ his capital as near
home as he can, and consequently as much as he can in the support of
domestic industry ; provided always that he can thereby obtain the ordi-
nary, or not a great deal less than the ordinary, profits of stock.
Thus upon equal or nearly equal profits, every wholesale merchant
EIGHTEENTH CENTURY POLITICAL ECONOMY 411
naturally prefers the home trade to the foreign trade of consumption,
and the foreign trade of consumption to the carrying trade. In the home
trade his capital is never so long out of his sight as it frequently is in the
foreign trade of consumption. He can know better the character and
situation of the persons whom he trusts, and, if he should happen to be
deceived, he knows better the laws of the country from which he must
seek redress. In the carrying trade, the capital of the merchant is, as it
were, divided between two foreign countries, and no part of it is ever
necessarily brought home, or placed under his own immediate view and
command. The capital which an Amsterdam merchant employs in car-
rying corn from Konigsberg to Lisbon, and fruit and wine from Lis-
bon to Konigsberg, must generally be the one-half of it at Konigsberg
and the other half at Lisbon. No part of it need ever come to Amster-
dam. The natural residence of such a merchant should either be at
Konigsberg or Lisbon, and it can only be some very particular circum-
stance which can make him prefer the residence of Amsterdam. The
uneasiness, however, which he feels at being separated so far from his
capital, generally determines him to bring that part both of the Konigs-
berg goods which he destines for the market of Lisbon, and of the Lisbon
goods which he destines for that of Konigsberg, to Amsterdam, and
though this necessarily subjects him to a double charge of loading and
unloading, as well as to the payment of some duties and customs, yet for
the sake of having some part of his capital always under his own view
and command, he willingly submits to this extraordinary charge ; and it
is in this manner that every country which has any considerable share of
the carrying trade, becomes always the emporium, or general market, for
the goods of all the different countries whose trade it carries on. The
merchant, in order to save a second loading and unloading, endeavours
always to sell in the home market as much of the goods of all those dif-
ferent countries as he can, and thus, so far as he can, to convert his
carrying trade into a foreign trade of consumption. A merchant, in the
same manner, who is engaged in the foreign trade of consumption, when
he collects goods for foreign markets, will always be glad, upon equal or
nearly equal profits, to sell as great a part of them at home as he can.
He saves himself the risk and trouble of exportation, when, so far as he
can, he thus converts his foreign trade of consumption into a home trade.
Home is in this manner the centre, if I may say so, round which the cap-
itals of the inhabitants of every country are continually circulating, and
towards which they are always tending, though by particular causes they
412 EIGHTEENTH CENTURY POLITICAL ECONOMY
may sometimes be driven off and repelled from it towards more distant
employments. But a capital employed in a home trade, it has already
been shown, necessarily puts into motion a greater quantity of domestic
industry and gives revenue and employment to a greater number of the
inhabitants of the country, than an equal capital employed in the for-
eign trade of consumption ; and one employed in the foreign trade of
consumption has the same advantage over an equal capital employed in
the carrying trade. Upon equal, or only nearly equal profits, therefore,
every individual naturally inclines to employ his capital in the manner
in which it is likely to afford the greatest support to domestic industry,
and to give revenue and employment to the greatest number of people of
his own country.
Secondly, every individual who employs his capital in the support
of domestic industry, necessarily endeavours to so direct that industry,
that its produce may be of the greatest possible value.
The produce of industry is what it adds to the subject or materials
upon which it is employed. In proportion as the value of this produce is
great or small, so will likewise be the profits of the employer. But it is
only for the sake of profit that any man employs a capital in the support
of industry ; and he will always, therefore, endeavour to employ it in the
support of that industry of which the produce is likely to be of the great-
est value, or to exchange for the greatest quantity either of money or of
other goods.
But the annual revenue of every society is always precisely equal to
the exchangeable value of the whole annual produce of its industry, or
rather is precisely the same thing with that exchangeable value. As
every individual, therefore, endeavours as much as he can both to
employ his capital in the support of domestic industry, and so to direct
that industry that its produce may be of the greatest value, every indi-
vidual necessarily labours to render the annual revenue of the society as
great as he can. He generally, indeed, neither intends to promote the
public interest, nor knows how much he is promoting it. By preferring
the support of domestic to that of foreign industry, he intends only his
own security ; and by directing that industry in such a manner as its pro-
duce may be of the greatest value, he intends only his own gain, and he is
in this, as in many other cases, led by an invisible hand to promote an
end which was no part of his intention. Nor is it always the worse for
the society that it was no part of it. By pursuing his own interest he fre-
quently promotes that of the society more effectually than when he really
EIGHTEENTH CENTURY POLITICAL ECONOMY 413
intends to promote it. I have never known much good done by those who
affected to trade for the public good. It is an affectation, indeed, not
very common among merchants, and very few words need be employed
in dissuading them from it.
What is the species of domestic industry which his capital can
employ, and of which the produce is likely to be of the greatest value,
every individual, it is evident, can, in his local situation, judge much bet-
ter than any statesman or lawgiver can do for him. The statesman who
should attempt to direct private people in what manner they ought to
employ their capitals would not only load himself with a most unneces-
sary attention, but assume an authority which could safely be trusted,
not only to no single person, but to no council or senate whatever, and
which would nowhere be so dangerous as in the hands of a man
who had folly and presumption enough to fancy himself fit to exercise it.
To give the monopoly of the home market to the produce of domes-
tic industry, in any particular art or manufacture, is in some measure to
direct private people in what manner they ought to employ their capitals,
and must, in almost all cases, be either a useless or a hurtful regulation.
If the produce of domestic can be brought there as cheap as that of for-
eign industry, the regulation is evidently useless. If it cannot, it must
generally be hurtful. It is the maxim of every prudent master of a fam-
ily never to attempt to make at home what it will cost him more to make
than to buy. The tailor does not attempt to make his own shoes, but
buys them of the shoemaker. The shoemaker does not attempt to make
his own clothes, but employs a tailor. The farmer attempts to make
neither the one nor the other, but employs those different artificers. All
of them find it for their interest to employ their whole industry in a way
in which they have some advantage over their neighbours, and to pur-
chase with a part of its produce, or, what is the same thing, with the
price of a part of it, whatever else they have occasion for.
What is prudence in the conduct of every private family, can scarce
be folly in that of a great kingdom. If a foreign country can supply us
with a commodity cheaper than we ourselves can make it, better buy it
of them with some part of the produce of our own industry, employed in
a way in which we have some advantage. The general industry of the
country, being always in proportion to the capital which employs it, will
not thereby be diminished, no more than that of the above mentioned
artificers, but only left to find out the way in which it can be employed
with the greatest advantage. It is certainly not employed to the greatest
414 EIGHTEENTH CENTURY POLITICAL ECONOMY
advantage when it is thus directed towards an object which it can buy
cheaper than it can make. The value of its annual produce is certainly
more or less diminished when it is thus turned away from producing
commodities evidently of more value than the commodity which it is
directed to produce. According to the supposition, that commodity could
be purchased from foreign countries cheaper than it can be made at
home. It could, therefore, have been purchased with a part only of the
commodities, or, what is the same thing, with a part only of the price of
the commodities, which the industry employed by an equal capital would
have produced at home, had it been left to follow its natural course. The
industry of the country, therefore, is thus turned away from a more to a
less advantageous employment, and the exchangeable value of its annual
produce, instead of being increased, according to the intention of the
lawgiver, must necessarily be diminished by every such regulation.
By means of such regulations, indeed, a particular manufacture
may sometimes be acquired sooner than it could have been otherwise,
and after a certain time may be made at home as cheap or cheaper than
in the foreign country. But though the industry of the society may be
thus carried with advantage into a particular channel sooner than it
could have been otherwise, it will by no means follow that the sum total,
either of its industry or of its revenue, can ever be augmented by any
such regulation. The industry of the society can augment only in pro-
portion as its capital augments, and its capital can augment only in pro-
portion to what can be gradually saved out of its revenue. But the imme-
diate effect of every such regulation is to diminish its revenue, and what
diminishes its revenue is certainly not very likely to augment its capital
faster than it would have augmented of its own accord, had both capital
and industry been left to find out their natural employments.
Though for want of such regulations the society should never ac-
quire the proposed manufacture, it would not, upon that account, neces-
sarily be the poorer in any one period of its duration. In every period of
its duration its whole capital and industry might still have been em-
ployed, though upon different objects, in the manner that was most
advantageous at the time. In every period its revenue might have been
the greatest which its capital could afford, and both capital and revenue
might have been augmented with the greatest possible rapidity.
The natural advantages which one country has over another in pro-
ducing particular commodities are sometimes so great that it is acknowl-
edged by all the world to,be in vain to struggle with them. By means of
EIGHTEENTH CENTURY POUTICAI, ECONOMY 415
glasses, hot-beds, and hot-walls, very good grapes can be grown in Scot-
land, and very good wine, too, can be made of them, at about thirty times
the expense for which at least equally good can be brought from foreign
countries. Would it be a reasonable law to prohibit the importation of
all foreign wines, merely to encourage the making of claret and bur-
gundy in Scotland ? But if there would be a manifest absurdity in turn-
ing towards any employemnt thirty times more of the capital and indus-
try of the country than would be necessary to purchase from foreign
countries an equal quantity of the commodities wanted, there must be
an absurdity, though not altogether so glaring, yet exactly of the same
kind, in turning towards any such employment a thirtieth or even a
three-hundredth part more of either. Whether the advantages which one
country has over another be natural or acquired, is in this respect of no
consequence. As long as the one country has those advantages and the
other wants them, it will always be more advantageous for the latter
rather to buy of the former than to make. It is an acquired advantage
only which one artificer has over his neighbour who exercises another
trade ; and yet they both find it more advantageous to buy of one another
than to make what does not belong to their particular trades.
Merchants and manufacturers are the people who derive the great-
est advantage from this monopoly of the home market. The prohibition
of the importation of foreign cattle and of salt provisions, together with
the high duties upon foreign corn, which in times of moderate plenty
amount to a prohibition, are not near so advantageous to the graziers
and farmers of Great Britain as other regulations of the same kind are
to its merchants and manufacturers. Manufactures, those of the finer
kind especially, are more easily transported from one country to another
than corn or cattle. It is in the fetching and carrying manufactures,
accordingly, that foreign trade is chiefly employed. In manufactures a
very small advantage will enable foreigners to undersell our own work-
men, even in the home market. It will require a very great one to enable
them to do so in the rude produce of the soil. If the free importation of
foreign manufactures was permitted, several of the home manufactures
would probably suffer, and some of them perhaps go to ruin altogether,
and a considerable part of the stock and industry at present employed in
them would be forced to find out some other employment. But the freest
importation of the rude produce of the soil could have no such effect
upon the agriculture of the country.
If the importation of foreign cattle, for instance, was made ever so
416 EIGHTEENTH CENTURY POLITICAL ECONOMY
free, so few could be imported that the grazing trade of Great Britain
could be little affected by it. Live cattle are, perhaps, the only commodity
of which the transportation is more expensive by sea than by land. By
land, they carry themselves to market. By sea, not only the cattle, but
their food and their water, too, must be carried at no small expense and
inconveniency. The short sea between Ireland and Great Britain, indeed,
renders the importation of Irish cattle more easy. But though the free
importation of them, which was lately permitted only for a limited time,
were rendered perpetual, it could have no considerable effect upon the
interest of the graziers of Great Britain. Those parts of Great Britain
which border upon the Irish Sea are all grazing countries. Irish cattle
could never be imported for their use, but must be drove through those
very extensive countries, at no small expense and inconveniency, before
they could arrive at their proper market. Fat cattle could not be drove
so far. Lean cattle therefore only could be imported, and such importa-
tion could interfere, not with the interest of the feeding or fattening
countries, to which, by reducing the price of lean cattle, it would rather
be advantageous, but with that of the breeding countries only. The
small number of Irish cattle imported since their importation was per-
mitted, together with the good price at which lean cattle continue to sell,
seem to demonstrate that even the breeding countries of Great Britain
are never likely to be much affected by the free importation of Irish cat-
tle. The common people of Ireland, indeed, are said to have sometimes
opposed with violence the exportation of their cattle. But if the export-
ers had found any great advantage in continuing the trade, they could
easily, when the law was on their side, have conquered this mobbish
opposition.
Feeding and fattening countries, besides, must always be highly
improved, whereas breeding countries are generally uncultivated. The
high price of lean cattle, by augmenting the value of uncultivated land, is
like a bounty against improvement. To any country which was highly
improved throughout, it would be more advantageous to import its lean
cattle than to breed them. The province of Holland, accordingly, is said
to follow this maxim at present. The mountains of Scotland, Wales, and
Northumberland, indeed, are countries not capable of much improve-
ment, and seem destined by nature to be the breeding countries of Great
Britain. The freest importation of foreign cattle could have no other
effect than to hinder those breeding countries from taking advantage of
the increasing population and improvement of the rest of the kingdom,
EIGHTEENTH CENTURY POLITICAL ECONOMY 417
from raising their price to an exorbitant height, and from laying a real
tax upon all the more improved and cultivated parts of the country.
The freest importation of salt provisions, in the same manner, coul 1
have as little effect upon the interest of the graziers of Great Britain as
that of live cattle. Salt provisions are not only a very bulky commodity,
but when compared with fresh meat they are a commodity both of worse
quality, and as they cost more labour and expense, of higher price. They
could never, therefore, come into competition with the fresh meat,
though they might with the salt provisions of the country. They might be
used for victualling ships for distant voyages, and such like uses, but
could never make any considerable part of the food of the people. The
small quantity of salt provisions imported from Ireland, since their im-
portation was rendered free, is an experimental proof that our graziers
having nothing to apprehend from it. It does not appear that the price
of butchers' meat has ever been sensibly affected by it.
Even the free importation of foreign corn could very little affect the
interest of the farmers of Great Britain. Corn is a much more bulky
commodity than butchers' meat. A pound of wheat at a penny is as dear
as a pound of butchers' meat at fourpence. The small quantity of for-
eign corn imported even in times of the greatest scarcity, may satisfy our
farmers that they can have nothing to fear from the freest importation.
The average quantity imported, one year with another, amounts only,
according to the well-informed author of the tracts upon the corn trade,
to twenty-three thousand seven hundred and twenty-eight quarters of all
sorts of grain, and does not exceed the five hundred and seventy-first
part of the annual consumption. But as the bounty upon corn occasions
a greater exportation in years of plenty, so it must of consequence occa-
sion a greater importation in years of scarcity, than in the actual state of
tillage would otherwise take place. By means of it, the plenty of one year
does not compensate the scarcity of another, and as the average quantity
exported is necessarily augmented by it, so must likewise, in the actual
state of tillage, the average quantity imported. If there was no bounty,
as less corn would be exported, so it is probable that, one year with an-
other, less would be imported than at present. The corn merchants, the
fetchers and carriers of corn between Great Britain and foreign coun-
tries, would have much less employment, and might suffer considerably ;
but the country gentleman and farmers could suffer very little. It is in
the corn merchants, accordingly, rather than in the country gentleman
418 EIGHTEENTH CENTURY POLITICAL ECONOMY
and farmers, that I have observed the greatest anxiety for the renewal
and continuation of the bounty.
Country gentlemen and farmers are, to their great honour, of all
people the least subject to the wretched spirit of monopoly. The under-
taker of a great manufactory is sometimes alarmed if another work of
the same kind is established within twenty miles of him. The Dutch
undertaker of the woolen manufacture at Abbeville stipulated that no
work of the same kind should be established within thirty leagues of that
city. Farmers and country gentlemen, on the contrary, are generally
disposed rather to promote than to obstruct the cultivation of their
neighbour's farms and estates. They have no secrets, such as those of
the greater part of manufacturers, but are generally rather fond of com-
municating to their neighbours, and of extending as far as possible, any
new practice which they have found to be advantageous. Pius Questus,
says old Cato, stabilissimusque, minimeque invidiosus; minimeque male
cogitantes sunt, qui in eo studio occupati sunt. Country gentlemen and
farmers, dispersed in different parts of the country, cannot so easily com-
bine as merchants and manufacturers, who, being collected into towns
and accustomed to that exclusive corporation spirit which prevails in
them, naturally endeavour to obtain against all their countrymen the
same exclusive privilege which they generally possess against the inhab-
itants of their respective towns. They accordingly seem to have been
the original inventors of those restraints upon the importation of foreign
goods which secure to them the monopoly of the home market. It was
probably in imitation of them, and to put themselves upon a level with
those who they found were disposed to oppress them, that the country
gentlemen and farmers of Great Britain so far forgot the generosity
which is natural to their station as to demand the exclusive privilege of
supplying their countrymen with corn and butchers' meat. They did not
perhaps take time to consider how much less their interest could be
affected by the freedom of trade than that of the people whose example
they followed.
To prohibit by a perpetual law the importation of foreign corn and
cattle is, in reality, to enact that the population and industry of the coun-
try shall at no time exceed what the rude produce of its own soil can
maintain.
There seem, however, to be two cases in which it will generally be
advantageous to lay some burden upon foreign for the encouragement of
domestic industrv.
EIGHTEENTH CENTURY POLITICAL ECONOMY 419
The first is, when some particular sort of industry is necessary for
the defense of the country. The defense of Great Britain, for example,
depends very much upon the number of its sailors and shipping. The
Act of Navigation, therefore, very properly endeavours to give the sail-
ors and the shipping of Great Britain the monopoly of the trade of their
own country, in some cases by absolute prohibitions, and in others by
heavy burdens upon the shipping of foreign countries. The following
are the principal dispositions of this act :
First, all ships, of which the owners, masters, and three-fourths of
the mariners are not British subjects, are prohibited, upon pain of for-
feiting ship and cargo, from trading to the British settlements and plan-
tations, or from being employed in the coasting trade of Great Britain.
Secondly, a great variety of the most bulky articles of importation
can be brought into Great Britain only, either in such ships as are above
described, or in ships of the country where those goods are produced,
and of which the owners, masters, and three-fourths of the mariners are
of that particular country ; and when imported even in ships of this lat-
ter kind, they are subject to double aliens-duty. If imported in ships of
any other country, the penalty is forfeiture of ship and goods. When
this Act was made, the Dutch were, what they still are, the great carriers
of Europe, and by this regulation they were entirely excluded from
being the carriers to Great Britain, or from importing to us the goods of
any other European country.
Thirdly, a great variety of the most bulky articles of importation are
prohibited from being imported, even in British ships, from any country
but that in which they are produced, upon pain of forfeiting ship and
cargo. This regulation, too, was probably intended against the Dutch.
Holland was then, as now, the great emporium for all European goods,
and by this regulation British ships were hindered from loading in Hol-
land the goods of any other European country.
Fourthly, salt fish of all kinds, whale-fins, whalebone, oil, and blub-
ber, not caught by and cured on board British vessels, when imported
into Great Britain, are subjected to double aliens-duty. The Dutch, as
they are still the principal, were then the only fishers in Europe that
attempted to supply foreign nations with fish. By this regulation a very
heavy burden was laid upon their supplying Great Britain.
When the Act of Navigation was made, though England and Hol-
land were not actually at war, the most violent animosity subsisted
between the two nations. It had begun during the government of the
420 EIGHTEENTH CENTURY POLITICAL ECONOMY
Long Parliament, which first framed this Act, and it broke out
soon after in the Dutch wars during that of the Protector and of Charles
the Second. It is not impossible, therefore, that some of the regulations
of this famous Act may have proceeded from national animosity. They
are as wise, however, as if they had all been dictated by the most delib-
erate wisdom. National animosity at that particular time aimed at the
very same object which the most deliberate wisdom would have recom-
mended, the diminution of the naval power of Holland, the only naval
power which could endanger the security of England.
The Act of Navigation is not favourable to foreign commerce, or to
the growth of that opulence which can arise from it. The interest of a
nation in its commercial relations to foreign nations is, like that of a
merchant with regard to the different people with whom he deals, to buy
as cheap and to sell as dear as possible. But it will be most likely to buy
cheap, when by the most perfect freedom of trade it encourages all na-
tions to bring to it the goods which it has occasion to purchase ; and for
the same reason, it will be most likely to sell dear, when its markets are
thus filled with the greatest number of buyers. The Act of Navigation,
it is true, lays no burden upon foreign ships that come to export the pro-
duce of British industry. Even the ancient aliens-duty, which used to be
paid upon all goods exported as well as imported, has, by several subse-
quent acts, been taken off from the greater part of the articles of exporta-
tion. But if foreigners, either by prohibitions or high duties, are hindered
from coming to sell, they cannot always afford to come to buy ; because,
coming without a cargo, they must lose the freight from their own coun-
try to Great Britain. By diminishing the number of sellers, therefore,
we necessarily diminish that of buyers, and are thus likely not only to
buy foreign goods dearer, but to sell our own cheaper, than if there was
a more perfect freedom of trade. As defense, however, is of much more
importance than opulence, the Act of Navigation is, perhaps, the wisest
of all commercial regulations of England.
The second case, in which it will generally be advantageous to lay
some burden upon foreign for the encouragement of domestic industry,
is when some tax is imposed at home upon the produce of the latter. In
this case it seems reasonable that an equal tax should be imposed upon
the like produce of the former. This would not give the monopoly of the
home market to domestic industry, nor turn towards a particular em-
ployment a greater share of the stock and labour of the country than
what would naturally go to it. It would only hinder any part of what
EIGHTEENTH CENTURY POLITICAL ECONOMY 421
would naturally go to it from being turned away by the tax into a less
natural direction, and would leave the competition between foreign and
domestic industry, after the tax, as nearly as possible upon the same
footing as before it. In Great Britain, when any such tax is laid upon
the produce of domestic industry, it is usual at the same time, in order to
stop the clamorous complaints of our merchants and manufacturers, that
they will be undersold at home, to lay a much heavier duty upon the
importation of all foreign goods of the same kind.
This second limitation of the freedom of trade, according to some
people should, upon some occasions, be extended much further than to
the precise foreign commodities which could come into competition with
those which had been taxed at home. When the necessaries of life have
been taxed in any country, it becomes proper, they pretend, to tax not
only the like necessaries of life imported from other countries, but all
sorts of foreign goods which can come into competition with anything
that is the produce of domestic industry. Subsistence, they say, becomes
necessarily dearer in consequence of such taxes ; and the price of labour
must always rise with the price of the labourer's subsistence. Every
commodity, therefore, which is the produce of domestic industry, though
not immediately taxed itself, becomes dearer in consequence of such
taxes, because the labour which produces it becomes so. Such taxes,
therefore, are really equivalent, they say, to a tax upon every particular
commodity produced at home. In order to put domestic upon the same
footing with foreign industry, therefore, it becomes necessary, they
think, to lay some duty upon every foreign commodity, equal to this
enhancement of the price of the home commodities with which it can
come into competition.
Whether taxes upon the necessaries of life, such as those in Great
Britain upon soap, salt, leather, candles, etc., necessarily raise the price
of labour, and consequently that of all other commodities, I shall con-
sider hereafter, when I come to treat of taxes. Supposing, however, in
the meantime, that they have this effect, and they have it undoubtedly,
this general enhancement of the price of all commodities, in consequence
of that of labour, is a case which differs in the two following respects
from that of a particular commodity, of which the price was enhanced by
a particular tax immediately imposed upon it.
First, it might always be known with great exactness how far the
price of such a commodity could be enhanced by such a tax ; but how far
the general enhancement of the price of labour might affect that of every
422 EIGHTEENTH CENTURY POLITICAL ECONOMY
different commodity, about which labour was employed, could never be
known with any tolerable exactness. It would be impossible, therefore,
to proportion with any tolerable exactness the tax upon every foreign, to
this enhancement of the price of every home commodity.
Secondly, taxes upon the necessaries of life have nearly the same
effect upon the circumstances of the people as a poor soil and a bad cli-
mate. Provisions are thereby rendered dearer in the same manner as if
it required extraordinary labour and expense to raise them. As in the
natural scarcity arising from soil and climate, it would be absurd to
direct the people in what manner they ought to employ their capitals and
industry, so it is likewise in the artificial scarcity arising from such taxes.
To be left to accommodate, as well as they could, their industry to their
situation, and to find out those employments in which, notwithstanding
their unfavourable circumstances, they might have some advantage
either in the home or in the foreign market, is what in both cases would
evidently be most for their advantage. To lay a new tax upon them,
because they are already overburdened with taxes, and because they
already pay too dear for the necessaries of life, to make them likewise
pay too dear for the greater part of other commodities, is certainly a
most absurd way of making amends.
Such taxes, when they have grown up to a certain height, are a
curse equal to the barrenness of the earth and the inclemency of the
heavens ; and yet it is in the richest and most industrious countries that
they have been most generally imposed. No other countries could sup-
port so great a disorder. As the strongest bodies only can live and enjoy
health under an unwholesome regimen, so the nations only, that in every
sort of industry have the greatest natural and acquired advantages, can
subsist and prosper under such taxes. Holland is the country in Europe
in which they abound most, and which from peculiar circumstances con-
tinues to prosper, not by means of them, as has been most absurdly sup-
posed, but in spite of them.
As there are two cases in which it will generally be advantageous to
lay some burden upon foreign, for the encouragement of domestic indus-
try, so there are two others in which it may sometimes be a matter of
deliberation : in the one, how far it is proper to continue the free importa-
tion of certain foreign goods ; and in the other, how far or in what man-
ner it may be proper to restore that free importation after it has been for
some time interrupted.
The case in which it may sometimes be a matter of deliberation how
EIGHTEENTH CENTURY POLITICAL ECONOMY 423
far it is proper to continue the free importation of certain foreign goods,
is when some foreign nation restrains by high duties or prohibitions the
importation of some of our manufactures into their country. Revenge in
this case naturally dictates retaliation, and that we should impose the
like duties and prohibitions upon the importation of some or all of their
manufactures into ours. Nations, accordingly, seldom fail to retaliate in
this manner. The French have been particularly forward to favour their
own manufactures by restraining the importation of such foreign goods
as could come into competition with them. In this consisted a great part
of the policy of M. Colbert, who, notwithstanding his great abilities,
seems in this case to have been imposed upon by the sophistry of mer-
chants and manufacturers, who are always demanding a monopoly
against their countrymen. It is at present the opinion of the most intelli-
gent men in France that his operations of this kind have not been bene-
ficial to his country. That minister, by the tariff of 1667, imposed very
high duties upon a great number of foreign manufactures. Upon his
refusing to moderate them in favour of the Dutch, they in 1671 prohib-
ited the importation of the wines, brandies, and manufactures of France.
The war of 1672 seems to have been in part occasioned by this commer-
cial dispute. The peace of Nimeguen put an end to it in 1678, by
moderating some of those duties in favour of the Dutch, who in conse-
quence took off their prohibition. It was about the same time that the
French and English began mutually to oppress each other's industry, by
the like duties and prohibitions, of which the French, however, seem to
have set the first example. The spirit of hostility which has subsisted
between the two nations ever since, has hitherto hindered them from
being moderated on either side. In 1697 the English prohibited the
importation of bone-lace, the manufacture of Flanders. The govern-
ment of that country, at that time under the dominion of Spain, prohib-
ited in return the importation of English woolens. In 1700, the
prohibition of importing bone-lace into England was taken off, upon con-
dition that the importation of English woolens into Flanders should be
put on the same footing as before.
There may be good policy in retaliations of this kind, when there is
a probability that they will procure the repeal of the high duties or pro-
hibitions complained of. The recovery of a great foreign market will
generally more than compensate the transitory inconveniency of paying1
dearer during a short time for some sorts of goods. To judge whether
such retaliations are likely to produce such an effect, does not perhaps,
424 EIGHTEENTH CENTURY POLITICAL ECONOMY
belong so much to the science of a legislator, whose deliberations ought
to be governed by general principles which are always the same, as to the
skill of that insidious and crafty animal, vulgarly called a statesman or
politician, whose councils are directed by the momentary fluctuations of
affairs. When there is no probability that any such repeal can be pro-
cured, it seems a bad method of compensating the injury done to certain
classes of our people, to do another injury ourselves, not only to those
classes, but to almost all the other classes of them. When our neighbours
prohibit some manufacture of ours, we generally prohibit, not only the
same, for that alone would seldom affect them considerably, but some
other manufacture of theirs. This may no doubt give encouragement to
some particular class of workmen among ourselves, and by excluding
some of their rivals, may enable them to raise their price in the home
market. Those workmen, however, who suffered by our neighbours'
prohibition will not be benefited by ours. On the contrary, they and
almost all the other classes of our citizens will thereby be obliged to pay
dearer than before for certain goods. Every such law, therefore, im-
poses a real tax upon the whole country, not in favour of that particular
class of workmen who were injured by our neighbours' prohibition, but
of some other class.
The case in which it may sometimes be a matter of deliberation, how
far or in what manner it is proper to restore the free importation of
foreign goods, after it has been for some time interrupted, is, when par-
ticular manufactures, by means of high duties or prohibitions upon all
foreign goods which can come into competition with them, have been so
far extended as to employ a great multitude of hands. Humanity may
in this case require that the freedom of trade should be restored only by
slow gradations, and with a good deal of reserve and circumspection.
Were those high duties and prohibitions taken away all at once, cheaper
foreign goods of the same kind might be poured so fast into the home
market, as to deprive all at once many thousands of our people of their
ordinary employment and means of subsistence. The disorder which
this would occasion might no doubt be very considerable. It would in
all probability, however, be much less than is commonly imagined, for
the two following reasons :
First, all those manufactures, of which any part is commonly ex-
ported to other European countries without a bounty, could be very
little affected by the freest importation of foreign goods. Such manu-
factures must be sold as cheap abroad as any other foreign goods of the
EIGHTEENTH CENTURY POLITICAL ECONOMY 423
same quality and kind, and consequently must be sold cheaper at home.
They would still, therefore, keep possession of the home market, and
though a capricious man of fashion might sometimes prefer foreign
wares, merely because they were foreign, to cheaper and better goods of
the same kind that were made at home, this folly could, from the nature
of things, extend to so few that it could make no sensible impression
upon the general employment of the people. But a great part of all the
different branches of our woolen manufacture, of our tanned leather, and
of our hardware, are annually exported to other European countries
without any bounty, and these are the manufactures which employ the
greatest number of hands. The silk, perhaps, is the manufacture which
would suffer the most by this freedom of trade, and after it the linen,
although the latter much less than the former.
Secondly, though a great number of people should, by thus restor-
ing the freedom of trade, be thrown all at once out of their ordinary
employment and common method of subsistence, it would by no means
follow that they would thereby be deprived either of employment or sub-
sistence. By the reduction of the army and navy at the end of the late
war, more than a hundred thousand soldiers and seamen, a number equal
to what is employed in the greatest manufactures, were all at once
thrown out of their ordinary employment; but though they no doubt
suffered some inconveniency, they were not thereby deprived of all
employment and subsistence. The greater part of the seamen, it is prob-
able, gradually betook themselves to the merchant service as they could
find occasion, and in the meantime both they and the soldiers were ab-
sorbed in the great mass of the people and employed in a great variety of
occupations. Not only no great convulsion, but no sensible disorder
arose from so great a change in the situation of more than a hundred
thousand men, all accustomed to the use of arms, and many of them to
rapine and plunder. The number of vagrants was scarce anywhere sen-
sibly increased by it, even the wages of labour were not reduced by it in
any occupation, so far as I have been able to learn, except in that of
seamen in the merchant service. But if we compare together the habits
of a soldier and of any sort of manufacturer, we shall find that those of
the latter do not tend so much to disqualify him from being employed in
a new trade, as those of the former from being employed in any. The
manufacturer has always been accustomed to look for his subsistence
from his labour only ; the soldier to expect it from his pay. Application
and industry have been familiar to the one ; idleness and dissipation to
V 6-27
426 EIGHTEENTH CENTURY POLITICAL ECONOMY
the other. But it is surely much easier to change the direction of indus-
try from one sort of labour to another, than to turn idleness and dissi-
pation to any. To the greater part of manufactures besides, it has
already been observed, there are other collateral manufactures of so
similar a nature, that a workman can easily transfer his industry from
one of them to another. The greater part of such workmen, too, are
occasionally employed in country labour. The stock which employed
them in a particular manufacture before, will still remain in the country
to employ an equal number of people in some other way. The capital of
the country remaining the same, the demand for labour will likewise be
the same, or very nearly the same, though it may be exerted in different
places and for different occupations. Soldiers and seamen, indeed, when
discharged from the king's service, are at liberty to exercise any trade,
within any town or place in Great Britain and Ireland. Let the same
natural liberty of exercising what species of industry they please be
restored to all his Majesty's subjects in the same manner as to soldiers
and seamen; that is, break down the exclusive privilege of corpora-
tions and repeal the statute of apprenticeship, both which are real
encroachments upon natural liberty, and add to these the repeal of the
law of settlements, so that a poor workman, when thrown out of employ-
ment, either in one trade or in one place, may seek for it in another trade
or in another place, without the fear either of a prosecution or of a
removal, and neither the public nor the individuals will suffer much more
from the occasional disbanding of some particular class of manu-
factures, than from that of soldiers. Our manufacturers have no doubt
great merit with their country, but they cannot have more than those
who defend it with their blood, nor deserve to be treated with more
delicacy.
To expect, indeed, that the freedom of trade should ever be entirely
restored in Great Britain, is as absurd as to expect that an Oceana or
Utopia should ever be established in it. Not only the prejudices of the
public, but what is much more unconquerable, the private interests of
many individuals, irresistibly oppose it. Were the officers of the army
to oppose with the same zeal and unanimity any reduction in the num-
ber of forces, with which master manufacturers set themselves against
every law that is likely to increase the number of their rivals in the home
market ; were the former to animate their soldiers, in the same manner
as the latter inflame their workmen, to attack with violence and out-
rage the proposers of any such regulation; to attempt to reduce the
EIGHTEENTH CENTURY POLITICAL ECONOMY 427
army would be as dangerous as it has now become to attempt to diminish
in any respect the monopoly which our manufacturers have obtained
against us. This monopoly has so much increased the number of some
particular tribes of them that, like an overgrown standing army,
they have become formidable to the government, and upon many occa-
sions intimidate the legislature. The member of parliament who sup-
ports every proposal for strengthening this monopoly is sure to acquire
not only the reputation of understanding trade, but great popularity and
influence with an order of men whose numbers and wealth render them
of great importance. If he opposes them, on the contrary, and still
more, if he has authority enough to be able to thwart them, neither the
most acknowledged probity, nor the highest rank, nor the greatest pub-
lic services can protect him from the most infamous abuse and detrac-
tion, from personal insults, nor sometimes from real danger, arising
from the insolent outrage of furious and disappointed monopolists.
The undertaker of a great manufacture who, by the home markets
being suddenly laid open to the competition of foreigners, should be
obliged to abandon his trade, would no doubt suffer very considerably.
That part of his capital which had usually been employed in purchasing
materials and in paying his workmen might, without much difficulty,
perhaps, find another employment. But that part of it which was fixed
in workhouses, and in the instruments of trade, could scarce be disposed
of without considerable loss. The equitable regard, therefore, to his
interest requires that changes of this kind should never be introduced
suddenly, but slowly, gradually, and after a very long warning. The
legislature, were it possible that its deliberations could be always di-
rected, not by the clamorous importunity of partial interests, but by an
extensive view of the general good, ought upon this very account, per-
haps, to be particularly careful neither to establish any new monopolies
of this kind, nor to extend further those which are already established.
Every such regulation introduces some degree of real disorder into the
constitution of the State, which it will be difficult hereafter to cure with-
out occasioning another disorder.
How far it may be proper to impose taxes upon the importation of
foreign goods, in order, not to prevent their importation, but to raise a
revenue for Government, I shall consider hereafter when I come to treat
of taxes. Taxes imposed with a view to prevent, or even to diminish
importation, are evidently as destructive of the revenue of the customs
as of the freedom of trade.
THATCHER, OLIVER J
1
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