Philosophical Writings

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THEOLOGY . PHILOSOPHY

PHILOSOPHICAL WRITINGS
BY LEIBNIZ SELECTED AND
TRANSLATED BY MARY MORRIS
INTRODUCTION BY C. R. MORRIS

GOTTFRIED WILHELM LEIBNIZ, born in
1646 at Leipzig. Entered the University of
Leipzig at the age of fifteen. Obtained a
professorship at the University of Altdorf
before he was twenty-one. Elected F.R.S.
in 1670. In 1676 went to live at the Court
of Hanover and died in 1716.

PHILOSOPHICAL WRITINGS

LEIBNIZ

LONDON: J. M. DENT & SONS LTD.
NEW YORK: E. P. DUTTON & CO. INC.

All rights reserved

Made in Great Britain

at The Temple Press Letchworth

and decorated by Eric Ravilious

for

J. M. Dent & Sons Ltd.

Aldine House Bedford St. London

First Published in this Edition 1934

INTRODUCTION

GOTTFRIED WILHELM LEIBNIZ has been described as a man
of universal attainments and of almost universal genius.
A courtier, diplomat, scholar, mathematician and philo-
sopher, he is perhaps the most brilliant figure among modern
philosophers. The history of philosophy has always
recognized him as one of the greatest of system-builders.
Now in the twentieth century he receives in addition an
even higher esteem for the brilliance of some of his particular
ideas and for the close thinking of some of his detailed
arguments. With Descartes he shares the merit of having
a more authoritative insight into the method and value of
mathematics and physics than any other philosopher of the
first rank. And with Hume he shares the honour of setting
the stage for the rejuvenation of modern philosophy in the
critical philosophy of Kant.

Life and Character. Leibniz was born at Leipzig in
July 1646, thirteen years after the birth of Spinoza, and
four years before the death of Descartes. His father, who
died in 1652, had been for some years Professor of Moral
Philosophy at Leipzig. At the age of fifteen Leibniz
entered the university of that city; and in 1666 he became
a Doctor of Laws, but at Altdorf, the university town of
Nuremburg, where he declined the offer of a professorship.
In the following year he entered the political service of
the powerful Elector-Archbishop of Mainz. Sent to Paris
in 1672 on a diplomatic mission to Louis XIV, he was
enabled to have some intercourse with learned men of his
day, notably with Arnauld and Malebranche. Early in the
next year he paid a short visit to London, where he met
Oldenburg, the first secretary of the Royal Society, and
Boyle. On his return to Paris he devoted himself to the
study of geometry under the guidance of Huygens.

vii

viu INTRODUCTION

Previously he had mainly concerned himself with problems
of logic and metaphysic. In 1676 he completed his dis-
covery of the Differential Calculus. There is no doubt
that Newton had been using a similar method for some years
previously. But it seems probable that Leibniz discovered
it independently; and the form in which he presented it has
been universally adopted in preference to that of Newton.

After the death of the Elector of Mainz, he accepted in
1676, after some hesitation, the position of librarian to the
learned John Frederick, Duke of Brunswick, and Hanover
became his headquarters for the remaining forty years of
his life. He thus lived in the atmosphere of the local
politics of a German principality. But his writings make
it clear that he was primarily interested in the wider
development of European civilization. For a time he was
connected with the learned life of Berlin through his friend-
ship with the Electress Sophia and her daughter Sophia-
Charlotte, afterwards Queen of Prussia. With the help of
the latter he was largely responsible for the institution in
1700 of an Academy in Berlin, of which he was made life
President. He made some attempts to secure the founda-
tion of similar academies in Dresden, St. Petersburg, and
Vienna ; but Europe was too much interested in wars, and he
met with no ultimate success. In 1712, on his last visit to
Vienna, he received the honour of a Privy Councillorship
and Barony of the Empire.

When he returned to Hanover, the Elector George had
already gone to England. Leibniz wished to go to London
for the coronation, but was ordered to remain at Hanover
and to continue his work on his history of Brunswick. He
seems never to have found favour with George I, whose
displeasure increased after his accession to the throne of
England; this was possibly due to the influence of friends
of Newton. In the last years of his life Leibniz was almost
entirely neglected, and his death in 1716 aroused no interest
in London or Berlin. No one from the Court attended
his funeral, his coffin being followed to the grave by his
secretary alone. In Paris, however, a fitting memorial
oration was pronounced by Fontenelle.

Throughout his life Leibniz was indefatigably industrious,

INTRODUCTION ix

and was impatient of the ill-health that his long hours
sometimes caused. He enjoyed social intercourse of all
kinds, thinking that there must always be something that
he could learn from everybody. This did not prevent him
from being extremely proud of his own ideas, and extremely
confident of the correctness of his own opinions. But he
never lost his enthusiasm to learn, nor relaxed his deter-
mination to examine every problem which occupied him
with complete thoroughness. In controversy he showed
himself to be exceptionally patient and good-tempered;
and in general, his secretary tells us, he spoke well of
everybody and made the best of everything.

Philosophical System : the Monadology, etc. It has already
been said that to-day the main philosophic interest of
Leibniz lies less in his system, considered as a system, than
in the particular arguments by which the development of
that system was influenced. We shall therefore give here
only a brief summary of his systematic doctrines, and then
turn to consider at greater length his treatment of some
special problems in his less formal writings.
/ Everything which has any reality, according to Leibniz,
must itself either be a real unity or be made up of real
unities. It is evident at once that bodies are not them-
selves real unities; they must therefore be aggregates of
real unities. A real unity must be simple, indivisible,
imperishable in the ordinary course of nature, and capable
of variety without having parts. There is one thing in
experience which we know to have all these characteris-
tics, namely, a soul. Now the unities of which bodies
are composed cannot actually be souls because they have
no consciousness; they must therefore be, as it were,
souls-without-consciousness, entities which have all the
characteristics of souls except consciousness. We may say
then that these souls-without-consciousness and souls,
properly so called, are the only real unities conceivable to
us. The name which Leibniz uses to cover all real unities
is monads. J

Since the/ monad has no parts it can only come into
being all at once and end all at once; that is, it can come

x INTRODUCTION

into being only by being created by God, and can come
to an end only by being annihilated by God. For the same
reason, Leibniz says, it cannot be changed internally by the
action upon it of things outside it, as a compound could. Yet
every monad has some character to distinguish it from
every other monad, and is subject to change. Its character
and its changes must therefore be determined by sonW
internal principle, which is essential to it. So from thi
moment of its creation every monad is pregnant with its
own future. No other monad can affect it in any wayj
what happens to it is determined by its own nature alonei
The action by which it passes from one state to another
Leibniz calls qpfetition.

Though the monads cannot act upon one another, they
are nevertheless adapted to one another, so that taken
all together they form a universe; in a word, they are
connected together and adapted to one another as if they
acted upon one another. This connection and adaptation
is governed by two laws: the principle of contradiction,
which determines what is possible and what is impossible,
and the principle of sufficient reason, in accordance with
which the Author of the universe, by free decisions of His
will, selects out of the infinite possibilities that which is
best and most fitted for existence. Each monad, in pro-
ducing its own changes by its own internal principle,
since its changes fit in with the changes which are produced
in themselves by all the other monads may be said to
express or represent the universe from its own point of
view. The passing state of the monad, representing as it
does the whole universe, is called perception.

Not every perception is apperceived. There are monads
which never have any consciousness at all ; and even minds
have an infinite number of unconscious perceptionsyilonads
without consciousness, of which bodies are composed, act
according to the laws of efficient causes; souls act according
to the laws of final causes. Since the changes of every
monad of whatever kind are adapted to the changes of every
otl^er, it is clear that the kingdom of efficient causes and the
kingdom of final causes are in harmony with one another.

Among souls a distinction must be made between minds

INTRODUCTION xi

and ordinary souls. In ordinary souls, for instance the
souls of brutes, there is some connection between conscious
perceptions, in accordance with the laws of memory and
imagination; but minds, which have clear and distinct
apperceptions, are further gifted with reason. Ordinary
souls are the living mirrors of the universe of created
things, whereas minds are also images of the Divinity
himself, the Author of nature, and are capable of knowing
the system of the universe. This makes minds capable of
entering into a kind of society with God, so that they are
members of the City of Minds, the most perfect state under
the most perfect of monarchs. Just as within the world of
nature there is harmony, as we saw above, between the two
kingdoms of efficient and of final causes, so there is a
harmony between the physical kingdom of nature and the
moral kingdom of grace; that is, there is accord between
God as Architect of the machine of the universe and God
as Monarch of the divine City of Minds.

By reason of this harmony, there is no good action
without reward, and no evil action without punishment.
All things work together for the good of the righteous in a
universe which is the image of the infinite perfections of God.

Correspondence with Arnauld. Let us now attempt to
discover what considerations led Leibniz to the main con-
clusions which are basic to the structure of his system; in
other words, let us examine his more detailed discussion
of some particular points, and try to find out what special
problems he was primarily considering when he made up
his mind on the most essential matters.

It is clear that one of the most fundamental of Leibniz's
doctrines it is certainly one of the most curious is that
every substance is a real unity, simple in the sense of
having no parts, incapable of being acted upon by anything
outside itself, nd therefore productive of its own changes
by an internal principle. It is generally recognized to-day
that the best light on the development of this thesis is to be
found in the letters to Arnauld, where Leibniz seems to be
arguing that his whole view of the nature of substance
follows from a basic principle of logic, which he takes to be

xii INTRODUCTION

axiomatic ; namely, verae propositionis semper praedicatum
inest subjecto in a true proposition the predicate is always
included in the subject. The implications of this in regard
to general propositions have no doubt been recognized
previously, says Leibniz; but its implications in regard to
singular propositions are more startling. Certainly they
startled Arnauld, part-author of the Port-Royal Logic.
It has always been recognized, Leibniz argues, that the
predicates which can truly be asserted of a sphere must be
contained within the essential notion of a sphere; but it has
not been seen that the same must hold of the actual indivi-
dual sphere which Archimedes had placed upon his tomb.
It must have been included within the original notion of that
sphere that it would on a particular day be set upon that
grave. To take a more striking instance, everything which
can truly be predicated of Adam must be contained within
the essential notion of Adam; that is, the original notion
of Adam included once for all the notion of everything
that was going to happen to him, and thereby to the rest
of mankind, his descendants.

This doctrine at once stirred the theologian in Arnauld,
by raising in his mind difficulties about the freedom of God ;
and Leibniz had to attempt to show that he was not a
determinist in any theologically objectionable sense. But
with this dispute we are not for the moment concerned.
What concerns us is that Leibniz is arguing that the
principle praedicatum inest subjecto involves the denial of
any interaction between substances; and that in making
his point he is emphasizing a distinction between predicates
asserted of general concepts (sub specie generalitatis) and
predicates asserted of individuals (singularite r) . It is im-
portant to notice that he refuses to identify or confuse
the individual with a highly differentiated general concept
(i.e. with an infima species). Adam is not just the first
man, the husband of Eve, or an inhabitant of the garden
of Eden. He is the one unique Adam. And everything
which happened to him happened to him because it followed
from the essential motion of that one unique Adam by an
absolute necessity.

Thus it seems to follow that if in a true proposition the

INTRODUCTION xiii

predicate is included in the notion of the subject, and if
there can be any true propositions asserted of Adam
singulariter, then Adam cannot have been ever acted upon
by anything external to himself; and, more generally,
individual substances are incapable of interaction. But,
even if we pass without comment Leibniz's acceptance of
the first of these hypotheses, we naturally ask ourselves why
he did not regard his argument as amounting to a reductio
ad absurdum of the notion of individual substances. Why
did he not conclude that individuals are not substances,
and that we have no knowledge of any true singular
propositions ?

It seems that Leibniz was convinced by reading Spinoza
that any view which denied the substantiality of individuals
was inadmissible. Beyond this it is very difficult to say
anything clear and definite. Up to a point he is very
cautious about the imputation of substantiality; and he
thinks that philosophers generally are too ready to allow
that things are substances. A body, he says, is evidently
not a substance; a crowd is not a substance. But he seems
to take it for granted that individual selves are substances.
He further takes it for granted that, though bodies are not
substances, they are real existences of some kind, and
therefore they must be aggregates of substances. He also
holds that all general notions are incomplete notions. No
notion is complete except the notion of an individual. Thus
the notion of the First Man is not the notion of a substance;
but the notion of Adam is the notion of a substance. All
this, however, seems hardly to amount to any proof.
Leibniz seems to be doing no more than simply affirming
again and again his thesis that a substance is essentially an
individual or real unity, and that there is in the universe a
plurality of such substances. There is, however, a basic
conviction involved in the argument, namely, the conviction
that individual selves are real unities and must be repre-
sented as substances. For this conviction Leibniz offers
no defence, though perhaps he sometimes holds that we
are directly conscious of being real unities.

Dynamics and Physics. There is no doubt that Leibniz

xiv INTRODUCTION

thought that his discoveries in regard to dynamics supported
his general theory of substance. In view of the Cartesian
doctrine that the essence of material substance was ex-
tension, he always regarded his refutation of Descartes's
mechanics as a vital part of the defence of his own system.

Descartes taught that the total quantity of motion in
nature is always the same. Leibniz argues that the
quantity of motion in nature is not constant, but (what
Descartes did not know) that the quantity of motion in any
given direction is constant. This principle he formulated
by saying that the total cause is equivalent to the total effect.
It had always been recognized that effects were proportional
to causes: but Leibniz now asserted that the total effect
was not simply proportional, but equivalent to the total
cause. In other words, to every action there is an equal
reaction.

Leibniz also regarded himself as having proved that the
total quantity of force in nature remains constant, force
being proportional not, as Descartes thought, to the pro-
duct of the mass and the velocity (mv), but to the product
of the mass and the square of the velocity (mv*, i.e. double
what is now called kinetic energy). The two formulae
(mv and mv 2 ) give the same result only in cases of equi-
librium. In a system of moving bodies mv is demonstrably
not constant; whereas mv* can be shown to be always the
same. Since God has not made a faulty machine, it is
evident that in nature the total quantity of force is
conserved.

Thus if we wish to understand the principle of change in
the physical universe, Leibniz argues, what we have to
consider is not motion but force. Now force is calculated
by looking at its effects. But it cannot be maintained, of
course, that the force is its effect. The effects are in the
future, whereas the force is in the body now. But what
exactly is meant by saying that the force is in the body?
We do not mean, according to Leibniz, that the body is
actually being active. To say that a body is endowed
with a certain force is different from saying that it is actually
doing work. On the other hand we do not mean by force
the mere potency of the Schoolmen; for that which has mere

INTRODUCTION xv

potency requires the realization of some external condition
(that is, it requires the action of something outside upon it)
to turn its potency into actuality. Force is thus neither
actual activity nor mere potency, but something between
the two.

Leibniz thus concludes that his dynamics forces him to
maintain that physical objects are made up of units whose
essence it is to be endowed with force (vis viva), and
which, therefore, do not need the action of one unit upon
another in order to produce change. Actually, of course,
it is difficult to see how Leibniz can have thought that
his dynamics supported the doctrine that each unit is a
substance or real unity, quite incapable of being affected
by any other unit. As he sometimes admits, dynamics
must think in terms of interaction. But of this we shall
have more to say presently, when we come to consider the
Correspondence with Clarke.

The New System, and the Controversy with Bayle. Here
Leibniz is primarily concerned to explain and defend his
doctrine of pre-established harmony, with special reference
to the union of body and soul. In doing so he shows that
his general view of substance partly depends on a careful
investigation of the nature of the mind.

The doctrine of pre-established harmony, he says, really
follows from the conclusions already drawn about the
nature of substance. Since no substance can act on any
other substance, and yet the changes of the various sub-
stances are adapted to one another as if they did interact,
we must conclude that everything that happens to any
individual substance 'springs from within itself by a
perfect spontaneity with regard to itself, and yet in a
perfect conformity with things outside '. Committed to this
conclusion by his analysis of propositions, Leibniz here
seeks to show that he can give a satisfactory account of
the union of soul and body. He does this especially by
examining the nature of the mind, and trying to show that
the doctrine that the mind produces of itself its own ex-
perience by virtue of its own inner nature agrees with the
facts of experience. It accords well with the fact of free-

xvi INTRODUCTION

will, as maintaining that all the soul's actions are produced
by itself alone, and with the fact of immortality, since if
nothing can affect the soul nothing can bring it to an end,
except a miracle; and on careful investigation we see he
alleges that it also accords with the facts of perception.

There are two main objections to his doctrine which
Leibniz here faces: first, that such automatism is in-
conceivable; secondly, that even if such automatism is
possible, the facts of experience show that the mind is not
in reality such an automaton.

To the first objection Leibniz urges that automata
can actually be constructed which are capable of a great
variety of behaviour. No doubt it is beyond the power of
a human artificer to make an automaton which would
behave as my body is behaving. But it certainly cannot
be shown that such an automaton is in principle impossible.
And we must remember that on any view there is a great
difference between Nature's machines and ours, perhaps
amounting to a difference in kind. In short, we must
take it that there is no behaviour, however complicated,
which is in principle beyond the power of automatism.

In the course of answering the second objection, namely,
that the mind is not in fact such an automaton, Leibniz
conducts some important psychological investigations. He
reminds us first that it is inconceivable to us how body
can act on mind or mind on body. Though it may appear,
therefore, that when I am stung by a wasp, the pain felt
by my mind is immediately caused by what happens to
my body, we cannot accept that explanation. It is evident
that the cause of what happens in the mind, since it cannot
be sought in the body, must be sought in the mind. Nor
need we be disturbed by the fact that previous philosophers
have rejected the view that minds are automata. What
they were rejecting was the contention that minds are
mechanical, that is, that they are corporeal automata.
This we shall not maintain, says Leibniz. We hold that
bodies are automata and minds are automata, but that
between the two kinds there is a great difference. Every
mind changes as determined by its own essence in accor-
dance with the laws of its own nature; and every body does

INTRODUCTION xvii

the same. But the laws of the nature of mind are different
from those of the nature of body.

We must look then for an explanation of the present
state of a mind in previous states of the same mind, and
nowhere else whatever. If this were not so, there could be
no responsibility and no identity. Furthermore, we shall
find that on this principle we can give some explanation of
a number of obvious facts of experience which have hither-
to been unexplained. But this Leibniz works out in more
detail when he comes to consider the philosophy of Locke.

New Essays. Here, in considering the Essay on the
Human Understanding, Leibniz perforce gives his main
attention to problems connected with the nature of know-
ledge. His thought in this connection tends automatically
to fall into two parts, the one part psychological and the
other logical. In the first he argues rather in the manner
of Locke, and seeks to propound an account of the nature
of mind which will explain what he takes to be the observed
facts of experience, e.g. memory, habit, etc. But, holding
as he does that the conclusions of this part of his inquiry
are not incompatible with the teaching of the established
logic, he has, secondly, to expound what he takes to be the
essential teaching of that logic. For though he does not
think that the established logic needs any fundamental
modification, it is obvious that he must needs give it a
new and careful re-statement after studying Locke. This
is an absolutely vital part of Leibniz's philosophy, because,
as we have seen, his whole view of the nature of substance
depends largely on pressing the implications of the logical
principle praedicatum inest subjecto.

Let us first briefly consider Leibniz's psychological
teaching in the New Essays. Here the most striking thing
is perhaps his application of his law of continuity to mental
phenomena. Natura non facit saltum: there are no big
sudden changes in nature. When there appear to be big
sudden changes, the appearances must be deceiving us.
When a tennis ball, for instance, strikes a wall, it may appear
that at one moment the ball is moving forward with a
velocity of say 70 f .s., at the next moment it is at rest, and
B905

xviii INTRODUCTION

at the next it is moving back again with a velocity of 50 f.s.
But this cannot really be the case. In order to pass from
a velocity of 70 f.s. to a state of rest, the ball must have
slowed up gradually and have passed through all the
intermediate velocities between 70 f.s. and zero; and
similarly when it acquires a velocity of 50 f.s. in the other
direction. The same must be true, Leibniz says, of the
mind's experience. If we appear to pass immediately from
a feeling of pleasure to a feeling of acute pain, the ap-
pearance must be deceiving us. The mind must actually
have passed through all the intermediate states. Since we
are often not conscious of this gradual transition, we must
admit that a great deal goes on in the mind of which we are
not conscious. There are a great many perceptions which
we do not apperceive, and all these perceptions go to make
up the state of our minds at any given moment. The
existence of such perceptions can often be inferred from the
character of our conscious states, even though the percep-
tions cannot be themselves brought into consciousness.

All this brings Leibniz into conflict with Locke. To the
latter it seems absurd to speak of something happening in
the mind of which the mind is not conscious; though, as
Leibniz points out, he modifies this later by saying that
there can be nothing in the mind of which the mind has
never been conscious without ever acknowledging, how-
ever, the importance of this modification of his doctrine.
But surely, Leibniz urges, it is Locke's view that is absurd.
What are we to say of memory, and of habits and dis-
positions? It is impossible to explain memory or habits
without supposing that there may be in the mind, in some
sense, things of which the mind is not conscious. And if
this be granted in principle, it is purely a matter for detailed
investigation to discover whether or not there must be in
the mind some perceptions of which, as far as we can
discover, we have never been conscious at all. Leibniz
thinks that there certainly are such perceptions. Suppose
that it has been established that a wasp-sting normally
causes pain at the time; and suppose that on a particular
occasion my attention is so much engaged with what I
am doing that I do not notice any pain until the tension

INTRODUCTION xix

of my excitement relaxes, although I must actually have
been stung some time before. Are we to say that in this
case the mind had no pain at all during the intervening
time, though it would have had pain if I had not been
otherwise excited ? Are we to say, in fact, that a happening
in my body is correlated with a happening in my mind at
some times and not at others ? Surely not, Leibniz urges.
When something happens in my body, there is always a
corresponding happening in my mind. We must not
conclude, just because I am not conscious of any previous
event in my mind relevant to the explanation of my present
state, that there was no such event. Rather we must
examine my present state and seek to determine what must
previously have occurred in my mind, even though it
cannot be found in my conscious experience.

It is evident that, though Leibniz is applying his principle
of continuity over-crudely, he has here a very strong case.
But what use does he make of it? His point is that since
it cannot be maintained that there is nothing in the mind
of which we are not conscious, Locke's attack on 'innate
ideas' fails. Just as the veins, which are laid bare when
a block of marble is cut, were there in the marble before
they were discovered, so there are some ideas which are in
the mind from the beginning whether or not they have
yet been found there. Locke's argument fails to show that
they cannot be there; and there are good, logical reasons
for concluding that they must be there. For what account
can be given otherwise of universal and necessary truths,
such as are to be found in geometry and arithmetic?
Knowledge of these cannot be derived from experience; for
the observation of particular instances can never entitle
us to assert a universal proposition.

Thus according to Leibniz Locke's attack on the basis
of the established logic fails; and it is therefore open to
Leibniz to fall back on a doctrine which accords with that
logic to explain those necessary truths of which Locke can-
not consistently give an account. Necessary truths are
arrived at by the analysis of clear and distinct notions; and
these notions in turn are, by a special technique, simply
found in the mind. From the analysis of the original

xx INTRODUCTION

clear and distinct notions we come, by way of identical
propositions, to non-identical propositions, and then by
analysis of these to further propositions, and so on to
the whole body of knowledge. The most powerful engine
for producing this happy result, he says, is the syllogism,
though it is a mistake to regard it as the only one.

Herein Leibniz shows himself to be a rationalist indeed.
He even includes within this doctrine our knowledge of
contingent fact. He distinguishes indeed between truths
of reason and truths of fact. The first are in the sphere
of necessity and are known a priori: the latter are in the
sphere of contingency and are known a posteriori. But in
the end these too, according to Leibniz, are arrived at by the
analysis of clear and distinct notions which are found in the
mind, and not by mere sense-observation. Because these
truths are in the sphere of contingency, we must not make
the mistake of thinking that they are any the less certain.
True propositions about Adam follow as much from the
original notion of Adam as true propositions about tri-
angles follow from the original notion of triangularity. The
latter follow in accordance with the law of contradiction,
whereas the former follow by the law of sufficient reason.
But both are equally certain.

Thus in the end, according to Leibniz, none of our
knowledge is really derived from observation by the senses;
all of it springs from the analysis of original notions which
are in some sense found in the mind.

Correspondence with Clarke: Leibniz and Newton. In this
controversy with an authoritative exponent of the views of
Newton, Leibniz, in the closing years of his life, seeks
finally to set in order and to defend his views with special
reference to their bearing on mathematics and physics.
In view of the intrinsic interest of this subject and of the
at least superficial resemblance between Leibniz's teaching
and modern physical theory, it is perhaps worth while to
examine this issue at some length.

Leibniz agreed with the Cartesians in rejecting atoms.
The reasons which make, it impossible to believe that
perceptible bodily masses are perfectly inelastic and indi-

INTRODUCTION xxi

visible hold in the end with equal weight against atoms. In
this modern physicists would agree with Descartes and
Leibniz. But the latter goes on to reject the former's
primary elements, which, he says, are nothing but mathe-
matical points', they have position, but no magnitude and
no other characteristics whatever. But how can such
elements be put together in such a way as to aggregate into
a bodily mass ? No number of nothings, when put together,
can make a something. Yet this is what, according to
Leibniz, the doctrine of Descartes requires.

Now the truth is, Leibniz continues, that it is not to
extension, but to that which is extended, that we must turn
our attention. If we do so we shall see that the essence of
that which is extended is not extension, but something
else. Let us for the sake of argument suppose that matter
is passive, as Descartes thought, and let us consider a
piece of matter at rest. This is as a matter of fact, says
Leibniz, to speak abstractly, since real matter is not
passive and is never at rest. But let that pass for the
moment. Let us suppose that matter is passive, and let us
consider a body at rest. Now the essence of the matter of
the body is not its extension, but its solidity. This solidity
shows itself in two ways: the body resists penetration and
resists movement. Without impenetrability and inertia it
would not be a body; unless it had these characteristics it
could not be extended. Solidity cannot be explained in
terms of extension. Therefore even Descartes, who held
that matter was inert and passive, should have seen that
that which makes a body solid is an essential character
of body.

We have already seen how this criticism of the Cartesians
is gathered up into Leibniz's constructive view that the
essence of matter is vis viva, in terms of which both im-
penetrability and inertia can be explained.

At this point we should perhaps expect Leibniz to ask
himself the question which he has just asked of Descartes
with such destructive results. How can these elements,
or metaphysical points, as he calls them, be compounded
into a bodily mass? After all, they share with the Car-
tesian elements the characteristic of having no extended

xxii INTRODUCTION

magnitude. It is true that, while Descartes's elements have
no characteristic but position, those of Leibniz have the
positive characteristic of vis viva. But does this help to
explain mass ? Can a number of parts, whose sole character-
istic is active force, aggregate into a body ?

To this problem modern readers, I think, will expect
Leibniz to offer some such solution as the following : Each
unit has a certain quantity of force, and, though it has no
extension, it always has position; that is to say, at any
given moment the force always operates at a point. The
units act upon one another, acting of course not by impact,
but at a distance, as Newton held gravitation to act; and
the result of this interaction is that the elements, which
must be thought of as centres of force, move in such a way
as to present to the human observer the appearance of a
number of continuous bodily masses of finite size behaving
in certain ways. Perceptible bodies, together with then-
changes and motions, are only appearances; the realities
are the interacting centres of force.

It is true that this view gives rise to very great difficulties.
Suppose we allow that movements of invisible particles can
give rise to the appearance of a continuous surface; how
can there be motion without a body to move ? Can a centre
of force move? But to the modern reader these are, for
better or worse, accustomed difficulties; and he will
probably expect Leibniz to inaugurate some such view. To
do so would be to accept as ultimate realities the centres
of force, space and time (as implied by their position and
movement), and presumably a mind or minds (implied
by the existence of appearances). And it would be allowed
that the centres of force in moving could affect one another's
motion by action at a distance.

But it is evident that this was not Leibniz's view. He
held that the only ultimate realities are individual sub-
stances; that is, the metaphysical points, endowed with vis
viva, and minds. Nothing else has ultimate reality; and it
is clear to Leibniz that space and time are not individual
substances. What then are space and time? In the first
place Leibniz will have nothing to do with the notion of
action at a distance, or with that of empty space. All

INTRODUCTION xxiii

motion takes place in a plenum, and all action of body
on body is by impact. We have no experience, he says, of
a vacuum in nature; and if there were such a thing as
empty space, position or motion in it would be purposeless,
since, as every point would be absolutely homogeneous with
every other, there could be no reason for occupying one
point rather than another, nor for moving from one point
to another. Since there would be no reason for it, it would
be contrary to reason.

Moreover, in nature, Leibniz argues, position and motion
are never purposeless. A body cannot be moved from one
position to another and remain the same body in every
respect other than its position. To change the situation of
bodies is, contrary to the opinion of those who believe in
empty space, to change the bodies. If you move a block
of marble from Genoa to Paris, it may appear to make no
difference to anything but the mere position in space of
the marble. But this is not so. It really makes a difference
to the marble and to everything else in the universe. What
makes the difference is, of course, not change of position in
empty space, but the change in the interrelations of bodies
that is, in the end, a change in the order of active forces in
the universe.

Thus space and time are nothing but the order of real
existences, according to Leibniz. Perhaps his view can be
more clearly stated in this way: Bodies and movements of
bodies are not real existences, but ideal existences created
by the imagination. There is nothing real in the physical
universe behind the curtain of sense except individual
units of vis viva, which are not in space and time. Space
and time themselves are even further removed from real
existence than are bodies and movements of bodies. For
the notions of bodies in space and of change in time can
only be significant if there is empty space and empty time.
If the physical world is a plenum, space is nothing but an
arrangement of bodies, and time is nothing but an order
of changes. Now the whole notion of empty space and
empty time is a vulgar error. So space and time are not
only not ultimately real like the monads; they are less real
than bodies, being due to a confused perception of bodies.

xxiv INTRODUCTION

In a word, if we wish to understand the true nature of
reality we must banish from our minds all notions of space
and time. Instead we must conceive of an order of relations
between entities whose essence is active force. In conceiv-
ing of these entities as exercising their force in an ordered
system we must not think of them as operating at points
in space, or of the system as a mechanical system, excellently
as such a fancy may seem to satisfy the imagination. We
must think of real entities as acting intensively, rather in
the manner that a soul acts, though without the conscious-
ness which attends upon some of the activities of souls. If
we think of the universe as a system, or ordered unity, of
the activities of monads, we shall be in no danger of thinking
of space and time as real existences. Such a mistaken
notion would be entirely due to the action of the imagination.

Summary of Leibniz's Philosophy. We may now make a
tentative attempt to gather together the various strands of
thought which go to make the finished product of Leibniz's
system; though it will now be clear to the reader that any
such attempt at a final judgment must rest on a very
precarious basis.

First, Leibniz was profoundly affected by his discovery
of the implications of the fundamental principles of the
Scholastic logic when applied to singular propositions. This
convinced him that substances must be real unities, and
cannot be affected by anything outside themselves.
Secondly, he found that if the constituent elements of
things are real unities, they must be the only real unities;
since, if they are to keep their character as real unities, they
can only be compounded by aggregation. Thirdly, he
argued that we are given in experience an instance of such
a real unity, namely, the self; this unity is thought of as
indivisible into parts, but yet as capable of great variety.
Fourthly, he considered that an examination of the nature
of the mind bears out the view that it is unaffected in its
experience by anything outside itself; this, so far as it
goes, confirms the view that real unities are pregnant with
their own future. Fifthly, a sound dynamics reveals that
the essence of material substance is not extension, nor even

INTRODUCTION xxv

motion, but force, a character in things which is presup-
posed by solidity and motion; real unities must be conceived
to be endowed with force in the same manner as the soul
is endowed with activity. Sixthly, since there cannot be
any interaction between real unities, it follows that there
must be pre-established harmony, in order to give unity
to the universe; without this there would be a chaotic
plurality and everything would be purposeless, which is
absurd. Lastly, reality as such is governed not by me-
chanical laws, but by the law of sufficient reason ; the real
world is not the only possible world, but the best of possible
worlds; everything is ordered not by a mechanistic necessity,
but by the moral necessity to work for the highest good of
minds; this is achieved by making the kingdom of nature
subservient to the kingdom of minds, God being at once the
Architect of the one and the Monarch of the other.

Remarks and Criticisms. It is now time to suggest a few
brief criticisms at each point of the argument as we have
here represented it. First, if Leibniz's view of substance
follows from the doctrine praedicatum inest stibjecto, he
seems to offer no reason for subscribing to that doctrine
itself; he simply takes it as common ground between him-
self and the established logic. Secondly, when he maintains
that if parts are real unities wholes of those parts can only
be aggregates, he is arguing too much a priori, and is
reflecting too little on the implications of his own view that
all individual minds taken together form a unity in the
City of Minds under the monarchy of God. Moreover, his
contention that a simple being which has no parts is yet
capable of variety is insufficiently worked out; it is not
sufficient to refer to an instance in experience, namely, the
soul; he ought at least to indicate, for example, just how an
infinity of little perceptions go to make up the present state
of the soul. Thirdly, it is doubtful, as Hume emphasized,
whether it is clear in experience that the soul is entirely
simple and without parts. Fourthly, while Leibniz makes
good ground against Locke when he maintains that the
present experience of a particular mind is always partly
determined by the intrinsic nature of mind as such and

xxvi INTRODUCTION

partly by the previous experience of the particular mind,
and is never wholly determined (as it would be if the mind
were a tabula rasa) by the present action of things outside it;
yet his arguments stop short of proving that its experience
is entirely determined by the mind's own original nature.
Fifthly, though Leibniz was no doubt right in principle in
urging that physics must explain everything in terms of
force or activity of some kind, he seems to have been wrong
in thinking that dynamical theory could conform to his
doctrine of real unities; indeed he himself sometimes allows
that as far as dynamics is concerned its objects behave
as if there was interaction between them. Sixthly, since
Leibniz allows that everything in the universe, even in-
cluding minds, behaves in every way, because of the pre-
established harmony, as if there was interaction, he seems
to be left with no argument against the real interaction of
body on body and of mind on mind except the logical
argument from the principle praedicatum inest subjecto ; and
this principle seems to be open to objection. Lastly, Leibniz
can show that many who argue that this is not the best of
all possible worlds take insufficient account of the all-
inclusive, all-pervading unity of the universe; but he has
no argument to prove that this is the best possible world;
the most that he can do is to show that his optimism
cannot be finally refuted.

A brief note must be added here about Leibniz's teaching
in regard to freedom. His stress on the principle of
sufficient reason inevitably makes his ethical views central
to his system. Yet his ethics, for whatever reason, is
certainly the weakest part of his thought. It is really quite
clear that he must believe in some kind of predestination;
that is, he is, in ordinary non-Leibnizian language, some
kind of a determinist. Yet he will never say so. He can
pour scorn, of course, on the suggestion that God might leave
the future of the universe to chance. He can show, more-
over, that the principles underlying the determination of
my actions are different from the principles of geometry or
of mechanics. But though he may multiply distinctions
between the various kinds of determination, the important
fact remains that on his view my actions are determined,

INTRODUCTION xxvii

and are in principle predictable. It is difficult to see how
such a doctrine can leave room for any real freedom of the
will. It is true that, according to Leibniz, my actions are
determined by nothing but my own nature. But so are
the actions of the brutes, and of those monads which have
no consciousness. He sometimes tries to mark the dif-
ference between the determination of minds and physical
determination by saying that motives 'incline without
necessitating*. But, as far as its bearing on freedom is
concerned, this is nothing but words. The fact that I shall
do this action freely, he says, does not mean that it is
uncertain whether I shall do it. Nothing in the universe
is uncertain, because nothing can occur without a sufficient
reason. And this is Leibniz's last word. He points out
some important distinctions, but they do not enable him to
make out a case for free-will.

Influence of Leibniz. It may safely be said that until the
twentieth century Leibniz's influence on the development
of philosophy was exercised chiefly through Kant. Kant
was brought up on the systematized Leibnizianism of
Wolff. But the latter made no important original contri-
bution, and it was on the basis of the ideas of Leibniz
himself that Kant sought to revivify philosophy after the
sceptical influence of Hume.

There is no doubt that, especially in the New Essays,
Leibniz goes far towards leading up to Kant's Copernican
revolution in logic. He carefully examines Locke's
empiricism, and lays down the principle that the tabula
rasa theory of mind cannot account for the existence of
knowledge of universal and necessary truths, such as are
found in geometry and arithmetic. This point is accepted
without more ado as a starting-point by Kant and Hegel.
So also is the method, here used by Leibniz, of attempting
to refute a psychological theory of knowledge by arguing
from the possibility of the existence of universal and
necessary truths. Kant, who presses the method much
further, calls it the 'transcendental method 1 .

Leibniz agrees with Kant in conceding to Locke that all
knowledge must start with sense-experience, and also in

xxviii INTRODUCTION

denying that it can be wholly derived from sense-experience.
He goes further and makes the pregnant suggestion, nihil
est in intellects, quod non fuerit in sensu, excipe, nisi ipse
intellectus there is nothing in the understanding which was
not previously in the senses, except the understanding itself.
But it must be admitted that his happy phrase does not
suggest to him, though it may well have suggested to Kant,
the Kantian view that what is necessary to the possibility
of universal truths is the existence of categories, that is,
forms of spontaneous activity.

Leibniz further shows the way to Kant by emphasizing
the distinction between truths of reason on the one hand,
which are a priori , in the sphere of necessity, and concerned
with general notions of possibilities, and on the other truths
of fact, which are a posteriori, in the sphere of contingency,
and concerned with individuals or real existences. He did
not, however, see the necessity for abandoning what Kant
called the 'dogmatic* position in regard to truths of fact.
He recognized, with Kant, that particular facts cannot be
deduced from original notions in accordance with the laws
of contradiction; only general truths can be arrived at
in this way, and these suffer under the disadvantage that
their objects are not real existences. But he thought that
he could save 'dogmatic* rationalism by introducing the
new refinement of the principle of sufficient reason to
bridge the gap between knowledge of general truths and
knowledge of individuals. He did not see, what Kant
learned from Hume, that in the sphere of real existences
we cannot progress without a knowledge of causal relations,
which is clearly not arrived at by any analysis of original
notions. We have as a matter of fact no insight into the
sufficient reason for the happening of any event to any
individual. Because he did not see this, he did not recog-
nize that our knowledge of truths of fact is synthetic.
Instead, he stood by the established logic, and performed
the service of showing Kant how that logic must be stated
if it is to meet the difficulties, which he himself exhibited,
in regard to our knowledge of the physical world.

In a word, Leibniz showed, as against Locke, that we
cannot explain scientific knowledge if we suppose the mind

INTRODUCTION xxix

to be a tabula rasa; nor can we do so if we suppose
that nothing goes on in the mind except what meets the
eye of introspection. So far he indicated to Kant what
line he should take in meeting Locke's psychological
approach. But he allowed himself to be too much en-
couraged by his discovery that the doctrine of innate
ideas cannot be certainly refuted by an empirical inventory
of the contents of the mind; and so he thought that thia
doctrine could be defended absolutely, and that, with the
added refinement of the principle of sufficient reason,
'dogmatic* rationalism could be made to stand in despite
of Locke. It is quite true that the mind might be born
with some kind of innate knowledge of certain universal
notions; but, as Hume shows, even if this were so, it could
not help to explain our knowledge of real existences, since
it could not explain our knowledge of causal relations.
It is on this rock that Leibniz's rationalism breaks.

C. R. MORRIS.
1934.

BIBLIOGRAPHICAL NOTE

In the lifetime of Leibniz only one complete work of his on philosophy
was published: Essais de Theodicee sur la bonU de Dieu, la liberU de
?homme t et I'originc du mal, 1710. Other important philosophical
works are : the correspondence with Samuel Clarke on the principles of
natural philosophy and religion (published by Clarke, 1717); La
Mpnadologie, a sketch of his philosophic system (German trans. 1720,
original French not until 1840 in Erdmann's edition); Nouveaux Essais
sur VEntendement Humain (Raspe edition, 1765), being an answer to
John Locke's Essay on the Human Understanding] the Sy sterna Theo-
logicum (1819), which is an exposition of the doctrines of the Roman
Catholic Church, written in the cause of re-union between Protestantism
and Catholicism (the title was probably given to the work by an over-
zealous Catholic).

Translations of the above (other than the Clarke correspondence,
which contained a translation by Clarke of Leibniz's words in the
original 1717 edition) are: A System of Theology, trans, by C. W. Russell,
1850; The Philosophical Works of Leibnitz, trans, by G. M. Duncan
(containing the Monadology, the Clarke correspondence, many of the
shorter philosophical papers, an abridgment of the Theodicy, and
selections from the New Essays), 1890; The New Essays, trans, by
A. G. Langley (1896). Other translations: The Monadology, etc.,
trans, by R. Latta, 1898 and 1925; The Monadology, by H. W. Carr r

xxx INTRODUCTION

1930; A summary Account of Leibnitz's Memoir, addressed to Louis XIV,
recommending the Conquest of Egypt, 1803; Discourse on Metaphysics,
Correspondence with Arnauld, and The Monadology, trans, by G. R.
Montgomery, 1902; Early Mathematical Manuscripts of Leibnitz, trans,
by J. M. Child, 1920.

There exists at present no complete edition of the works of Leibniz,
and it may be said that all editions are supplementary in some way or
other. The best edition is that of C. J. Gerhardt (philosophical writings,
1875-90; mathematical writings, 1855-63). Next comes Onno Klopp's
edition of the historical and political writings (1864-77); and then that
of Foucher de Careil, which contains the theological works besides the
political works, and the writings bearing on the foundation of academies.
To these should be added the first 'collected' edition of L. Dutens
(1768), and that of G. H. Pertz (1843-63); the editions of the philo-
sophical works by Kaspe (1765), Erdmann (1840), Jacques (1846), and
Janet (1866). There is, however, in course of preparation, a complete
edition of the works of Leibniz, including all the papers in the Library
of Hanover, under the direction of the Akademie der Wissenschaften
of Berlin. It is intended to consist of forty quarto volumes, arranged
in seven series: (i) General, Political, and Historical Correspondence
(i i vols.) ; (2) Philosophical Correspondence (6 vols.) ; (3) Mathematical,
Scientific, and Technical Correspondence (5 vols.) ; (4) Political Writings
'4 vols.); (5) Historical Writings (4 vols.); (6) Philosophical Writings
6 vols.); (7) Mathematical, Scientific, anc Technical (4 vols.). Only
ive volumes have so far been issued (1934).

The standard biography is that by G. E. Guhrauer (1842). Works
in English are: The Life of G. W. von Leibnitz, by J. M. Mackie (1845),
a short book based on Guhrauer's; Leibniz, by J. T. Merz (1884);
A Critical Exposition of the Philosophy of Leibniz, by Bertrand Russell
(1900); Leibniz, by H. W. Carr (1929); The Reunion of the Churches, by
G. J. Jordan (1927), is a study of Leibniz's attempt at reunion. The
Dawn of Modern Thought, by S. H. Mallone (1930) contains a study of
Leibniz. Mention should also be made of E. Bodemann's catalogue, Die
Leibnizschnften in der Koniglichen Bibliothek zu Hannover (1895) from
which are translated one or two extracts in this volume.

TRANSLATOR'S PREFACE

THE passages from Leibniz's philosophical writings given in
this book are almost all taken from the seven volumes of
Gerhardt's edition. A few extracts in Part III are not taken
from Gerhardt, but their sources are indicated in footnotes.

Part I contains the three best known works among Leibniz's
more formal expositions of his system The Monadology
(1714), Principles of Nature and of Grace (1714), and On the
Ultimate Origination of Things (1697). These are given
complete. The Monadology is printed first in spite of its
date, because in addition to being the most famous of
Leibniz's writings, it is also, so to speak, his title-piece.

Part II represents an attempt to give evidence for a
balanced judgment about the scope and development of the
thought of Leibniz, and is arranged chronologically. Except
in the case of the Letter to Foucher (1676), the Letter to
Bayle (1687), and the New System of the Nature and
Communication of Substances (1695), substantial abridgment
has been necessary. Where the omissions are not made
clear by the numbering of the chapters or paragraphs, they
have been indicated by dots (....) or by footnotes. I
have tried, in abridging, only to cut out arguments which
are better or more appropriately dealt with elsewhere, so as
to concentrate attention on what seemed the central points
in the various works. In the Correspondence with Arnauld
(1686-7) I have regarded Leibniz as chiefly concerned with
deriving his doctrine of substance from the analysis of
propositions; in the controversy with Bayle (1695-1702) I
have represented his mathematician's interest in machines
and automata; in the New Essays (1702-3) passages are
given showing the development of his psychology and
indicating his statement of his logical doctrines, with special

xxxi

xxxii TRANSLATOR'S PREFACE

reference to his attitude to the syllogism; and in the Corre-
spondence with Clarke (1715) I have concentrated attention on
his defence of his physical and dynamical ideas, and of his
doctrines about space and time, since these writings represent
Leibniz's last and greatest attempt to state his case against
the theories of Newton.

Part III consists of short extracts which are intended to
illustrate the breadth and variety of Leibniz's interests, and
also his attitude to other men of learning of his time. A few
passages are included as specimens of his more fanciful
writing. The last (taken from the concluding pages of the
Theodicy) also gives as clear an idea as any other passage
of his standpoint with regard to freedom and predestination.

In translating I have thought it better to come to a
definite decision on all occasions, rather than to cumber
the text with footnotes about difficulties of interpretation.
The disadvantages of this method are perhaps seen at their
greatest in 12, 13 of the Monadology. Here, as elsewhere,
I have tried to give an exact rendering of the text rather
than to tighten it up, as it were, into accuracy or consistency.
Where Leibniz uses a vague word or phrase, I have tried to
give a correspondingly vague word or phrase in English.
Even so, however, I am aware that my translation is through-
out affected by my own interpretation of the author's
meaning; but I have tried to make it as philosophically
exact as possible.

To avoid multiplying footnotes I have given short notes
on the persons mentioned in the text in the Index of Proper
Names, and have added a full Philosophical Index to take
the place of cross references at the bottom of the page.

Of the existing English versions I have found Latta's to
be the best; though I have sometimes differed from him.
I have also consulted the translations of Wildon-Carr,
Montgomery, Duncan, and Langley.

1934. M. M.

CONTENTS

PAGE

INTRODUCTION ........ vii

BIBLIOGRAPHY xxix

TRANSLATOR'S PREFACE xxxi

PART I. THE PHILOSOPHICAL SYSTEM OF LEIBNIZ

THE MONADOLOGY. 1714 3

PRINCIPLES OF NATURE AND OF GRACE, FOUNDED

ON REASON. 1714 ...... 21

ON THE ULTIMATE ORIGINATION OF THINGS. 1697 3 2

PART II. THE DEVELOPMENT OF LEIBNIZ'S
PHILOSOPHY

LETTER TO FOUCHER. 1676 45

CORRESPONDENCE WITH ARNAULD. 1686 . . 52

LETTER TO BAYLE. 1687 88

EXPOSITION AND DEFENCE OF THE NEW SYSTEM. 1695 97
NEW ESSAYS ON THE HUMAN UNDERSTANDING . .141
CORRESPONDENCE WITH CLARKE . . . .192

PART III. MISCELLANEOUS EXTRACTS FROM

LEIBNIZ'S PHILOSOPHICAL WRITINGS . 231

INDEX OF PROPER NAMES 271

PHILOSOPHICAL INDEX . . . . . . 279

C95 xxxili

PART I

THE PHILOSOPHICAL SYSTEM OF
LEIBNIZ

THE MONADOLOGY. 1714

1. The monad, of which we shall speak here, is nothing
but a simple substance which enters into compounds; simple,
that is to say, without parts.

2. And there must be simple substances, because there are
compounds; for the compound is nothing but a collection or
aggregatum of simples.

3. Now where there are no parts, there neither extension,
nor shape, nor divisibility is possible. And these monads
are the true atoms of nature and, in a word, the elements of
things.

4. Moreover, there is no fear of dissolution, and there is no
conceivable way in which a simple substance could perish
in the course of nature.

5. For the same reason there is no way in which a simple
substance could begin in the course of nature, since it cannot
be formed by means of compounding.

6. Thus it may be said that monads can only begin and
end all at once, that is to say they can only begin by creation
and end by annihilation, whereas what is compound begins
or ends by parts.

7. There is also no means of explaining how a monad can
be altered or changed within itself by any other created thing,
since it is impossible to displace anything in it or to conceive
of the possibility of any internal motion being started,
directed, increased, or diminished within it, as can occur
in compounds, where change among the parts takes place.
Monads have no windows, by which anything could come in
or go out. Accidents cannot become detached, or wander
about outside substances, as the 'sensible species' of the

4 MONADOLOGY

Scholastics used to do. Thus neither substance nor accident
can enter a monad from without.

8. Monads, however, must have some qualities, otherwise
they would not be beings at all. And if simple substances
did not differ by their qualities, there would be no way of
perceiving any change in things, since what is in the com-
pound can only come from its simple ingredients; and if
monads were without qualities, they would be indistinguish-
able from one another, since they do not differ in quantity
either. And consequently, supposing space to be a plenum,
each place would always only receive, when motion occurred,
the equivalent of what it had before; and one state of things
would be indistinguishable from another.

9. Indeed, every monad must be different from every other.
For there are never in nature two beings, which are precisely
alike, and in which it is not possible to find some difference
which is internal, or based on some intrinsic quality.

10. I also take it as granted that every created thing, and
consequently the created monad also, is subject to change,
and indeed that this change is continual in each one.

11. It follows from what we have just said, that the natural
changes of monads come from an internal principle , since an
external cause would be unable to influence their inner being.

12. But besides the principle of change, there must be
differentiation within that which changes, to constitute as it
were the specification and variety of simple substances.

13. This differentiation must involve a plurality within
the unity or the simple. For since every natural change
takes place by degrees, something changes, and something
remains; and consequently the simple must contain a large
number of impressions and relations, although it has no
parts.

14. The passing state, which involves and represents a
plurality within the unity or simple substance, is nothing
other than what is called perception) which must be carefully

MONADOLOGY 5

distinguished from apperception, as will appear presently.
And herein lies the great mistake of the Cartesians, that they
took no account of perceptions which are not apperceived.
It is this also which made them believe that minds alone are
monads, and that neither 'brutes nor other entelechies have
souls. For the same reason also they fell into the common
error of confusing death, properly so called, with a prolonged
unconsciousness; and this made them favour the Scholastic
conviction that souls are entirely separate from bodies, and
even confirmed some ill-balanced minds in the opinion that
souls are mortal.

15. The action of the internal principle which produces the
change or passage from one perception to another may be
called appetition; it is true that the appetite cannot always
attain completely the whole of the perception at which it
aims, but it always attains something of it, and arrives at
new perceptions.

16. We ourselves experience plurality within a simple
substance, when we find that the least thought of which we
are conscious involves a variety in its object. So everyone
who acknowledges that the soul is a simple substance must
acknowledge this plurality within the monad; and M. Bayle
should not have found any difficulty in this, as he does in his
Dictionary, in the article 'Rorarius'.

17. We are moreover obliged to confess that perception and
that which depends on it cannot be explained mechanically,
that is to say by figures and motions. Suppose that there
were a machine so constructed as to produce thought, feeling,
and perception, we could imagine it increased in size while
retaining the same proportions, so that one could enter as
one might a mill. On going inside we should only see the
parts impinging upon one another; we should not see any-
thing which would explain a perception. The explanation
of perception must therefore be sought in a simple substance,
and not in a compound or in a machine. Moreover, there is

6 MONADOLOGY

nothing else whatever to be found in the simple substance
except just this, viz. perceptions and their changes. It is in
this alone that all the internal actions of simple substances
must consist.

18. We may give the name entelechies to all created simple
substances or monads. For they have in themselves a certain
perfection (e^ouo-t TO oreAes); there is a self-sufficiency
(avrdpKCia) in them which makes them the sources of their
internal actions incorporeal automata, if I may so
put it.

19. If we wish to give the name 'soul' to everything which
has perceptions and appetites in the general sense I have just
explained, all created simple substances or monads might be
called souls; but as feeling is something more than a simple
perception, I agree that the general name monad or en-
telechy should be enough for simple substances which have
no more than that, and that those only should be called souls,
whose perception is more distinct and is accompanied by
memory.

20. For there is to be found in our ordinary experience a
state, in which we remember nothing and have no distinguish-
able perception; as when we fall into a swoon, or when we are
overcome by a deep dreamless sleep. In this state the soul
does not sensibly differ from a simple monad; but as this
state is not permanent, and as the soul emerges from it, the
soul is something more.

21. And it does not follow that when in that state the
simple substance has no perception at all. Indeed, that is
not possible for the above reasons; for it cannot perish, nor
can it subsist without being affected in some way, and this
affection is nothing but its perception. But when there are
a very great number of small perceptions with nothing to
distinguish them, we are stupefied, just as it happens that if
we go on turning round in the same direction several times
running, we become giddy and go into a swoon, so that we

MONADOLOGY 7

can no longer distinguish anything at all. And death can
throw animals 1 into this state for a time.

22. And as every state of a simple substance is a natural
consequence of its preceding state, so that the present state
of it is big with the future,

23. and since, on awakening from our stupor, we are
conscious of our perceptions, it must be the case that we
received the perceptions the moment before, though we were
not conscious of them; for a perception cannot arise in the
course of nature except from another perception, as one
motion can only arise in the course of nature from another
motion.

24. From this we see that if we had nothing in our percep-
tions to distinguish them, nothing so to speak heightened
and of a keener savour, we should always be in this stupor.
And this is the state of bare monads.

25. We see also that Nature has given heightened per-
ceptions to animals from the care she has taken to provide
them with organs which collect several rays of light, or
several undulations of the air, so as to make these effective
by being united. There is something of the kind in smell,
taste, and touch, and perhaps in many other senses which are
unknown to us. I will explain later how what occurs in the
soul represents what takes place in the organs.

26. Memory provides souls with a kind of consecutiveness,
which copies reason but must be distinguished from it. What
I mean is this: we often see that animals, when they have a
perception of something which strikes them, and of which
they had a similar perception previously, are led, by the
representation of their memory, to expect what was united
with this perception before, and are carried away by feelings
similar to those they had before. For example, when dogs

1 By ' animals ' Leibniz means all living creatures up to and
including man. The lower animals, as distinguished from man,
he refers to as ' brutes '.

8 MONADOLOGY

are shown a stick, they remember the pain which it has
caused them in the past, and howl or run away.

27. The powerful imagination, which strikes and moves
them, arises either from the magnitude or from the number
of the preceding perceptions. For often a vivid impression
has in a moment the effect of long habit, or of many ordinary
perceptions oft repeated.

28. Men act like brutes in so far as the sequences of their
perceptions arise through the principle of memory only, like
those empirical physicians who have mere practice without
theory. We are all merely empiricists as regards three-
fourths of our actions. For example, when we expect it to
be day tomorrow, we are behaving as empiricists, because
until now it has always happened thus. The astronomer
alone knows this by reason.

29. But it is the knowledge of necessary and eternal
truths which distinguishes us from mere animals, and gives
us reason and the sciences, raising us to knowledge of our-
selves and God. It is this in us which we call the rational
soul or mind.

30. Further it is by the knowledge of necessary truths
and by their abstractions that we are raised to acts of re-
flection, which make us think of what is called the self, and
consider that this or that is within us. And it is thus that in
thinking of ourselves, we think of being, of substance, of the
simple and the compound, of the immaterial and of God
Himself, conceiving that what is limited in us, in Him is
limitless. And these acts of reflection provide the chief
objects of our reasonings.

31. Our reasonings are based on two great principles: the
principle of contradiction, by virtue of which we judge to be
false that which involves a contradiction, and true that
which is opposed or contradictory to the false;

32. and the principle of sufficient reason, by virtue of which
we consider that no fact can be real or existing and no pro-

MONADOLOGY 9

position can be true unless there is a sufficient reason, why
it should be thus and not otherwise, even though in most
cases these reasons cannot be known to us.

33. There are also two kinds of truths: truths of reasoning
and truths oifact. Truths of reasoning are necessary and
their opposite is impossible; those of fact are contingent and
their opposite is possible. When a truth is necessary, the
reason for it can be found by analysis, that is, by resolving
it into simpler ideas and truths until the primary ones are
reached.

34. It is in this way that in mathematics speculative
theorems and practical canons are reduced by analysis to
definitions, axioms, and postulates.

35. Finally there are simple ideas of which no definition
can be given; there are also axioms or postulates, or in a word
primary principles, which cannot be proved and have no
need of proof. These are identical propositions, whose
opposite contains an express contradiction.

36. But a sufficient reason also must be found in the case of
contingent truths or truths of fact; that is to say, in the case of
the series of things spread over the universe of created
things; otherwise resolution into particular reasons might
go on into endless detail on account of the immense variety
of things in nature and the division of bodies ad infinitum.
There are an infinite number of shapes and motions, both
present and past, which enter into the efficient cause of my
present writing; and there are an infinite number of minute
inclinations and dispositions of my soul, both present and
past, which enter into its final cause.

37. And as all this differentiation involves only other prior
or more differentiated contingent things, all of which need a
similar analysis to explain them, we are no further advanced :
and the sufficient or ultimate reason must be outside the
series of this differentiation of contingent things, however
infinite it may be.

io MONADOLOGY

38. This is why the ultimate reason of things must lie in
a necessary substance, in which the differentiation of the
changes only exists eminently as in their source; and this is
what we call God.

39. Now since this substance is a sufficient reason of all this
differentiation, which is itself likewise all connected, there is
only one God, and this God is enough.

40. We may also judge that since this Supreme Substance,
who is unique, universal, and necessary, has nothing outside
Himself independent of Himself, and is a simple series of
possible being, He must be incapable of being limited, and
must contain just as much reality as is possible.

41. Whence it follows that God is absolutely perfect, since
perfection is nothing but magnitude of positive reality, in the
strict sense, setting aside the limits or bounds in things which
are limited. And there, where there are no bounds, that is
to say in God, perfection is absolutely infinite.

42. It follows also that created things owe their per-
fections to the influence of God, but that they owe their
imperfections to their own nature, which is incapable of
being without limits. For it is in this that they are dis-
tinguished from God.

43. It is true likewise, that in God is the source not only of
existences but also of essences, in so far as they are real, that
is of all the reality there is in possibility. This is because
the Understanding of God is the region of eternal truths
and of the ideas on which they depend, and because without
Him there would be nothing real in the possibilities not only
nothing existent, but also nothing possible.

44. For if there is a reality in essences or possibilities, or
indeed in eternal truths, this reality must be founded on
something existent and actual; and consequently on the
existence of the Necessary Being in whom essence involves
existence, or in whom to be possible is itself to be actual.

45. Thus God alone (or the Necessary Being) has the

MONADOLOGY u

privilege that He must exist if He is possible. And as nothing
can prevent the possibility of that which has no limits, no
negation, and consequently no contradiction, this alone is
necessary to make us know the existence of God a priori.
We have proved it also by the reality of eternal truths. And
we have now just proved it a posteriori also, since there exist
contingent beings, which can only have their ultimate or
sufficient reason in the Necessary Being, who has the reason
for His being in Himself.

46. We must not, however, imagine, as some do, that
because the eternal truths are dependent on God, they are
therefore arbitrary and depend on His will, as Descartes,
and after him M. Poiret, seem to have thought. This is true
only of contingent truths, whose principle is fitness or the
choice of the best] whereas necessary truths depend solely on
His understanding, of which they are the internal object.

47. Thus God alone is the primary Unity, or original simple
substance, from which all monads, created and derived, are
produced, and are born, so to speak, by continual figurations
of the Divinity from moment to moment, limited by the
receptivity of the created being, which is of its essence
limited.

48. There is in God power, which is the source of every-
thing, knowledge, which contains the differentiation of the
ideas, and finally will, which causes change and production
according to the principle of what is best. And these
correspond to what provides the ground or basis in created
monads, the perceptive faculty and the appetitive faculty.
But in God these attributes are absolutely infinite or perfect,
while in created monads or in entelechies (or perfectihdbiae,
as Hermolaus Barbarus translated this word) there are only
limitations of them, in proportion to the perfection there is
in the monad.

49. The created thing is said to act outwardly in so far as
it has perfection, and to be passively affected by another in so

12 MONADOLOGY

far as it is imperfect. Thus activity is attributed to the
monad in so far as it has distinct perceptions, and passivity
in so far as it has confused perceptions.

50. And one created thing is more perfect than another
when there is found in it that which explains a priori what
happens in the other; and it is because of this that we say
that it acts upon the other.

51. But in simple substances the influence of one monad
over another is ideal only; it can have its effect only through
the intervention of God, inasmuch as in the ideas of God a
monad rightly demands that God, in regulating the rest from
the beginning of things, should have regard to itself. For
since it is impossible for a created monad to have a physical
influence on the inner nature of another, this is the only way
in which one can be dependent on another.

52. And this is why actions and passions are mutual
between created things. For when God compares two
simple substances he finds in each reasons which oblige Him
to adapt the other to it, and consequently what is active in
certain aspects is passive from another point of view: active
in so far as what is distinctly known in it explains what
occurs in another, and passive in so far as what occurs in
it is distinctly known in another.

53. Now as there is an infinite number of possible uni-
verses in the ideas of God, and as only one can exist, there
must be a sufficient reason for God's choice, determining
Him to one rather than to another.

54. And this reason can only be found in the fitness, or
in the degrees of perfection, which these worlds contain,
each possible world having the right to claim existence in
proportion to the perfection which it involves.

55. And it is this which causes the existence of the best,
which God knows through His wisdom, chooses through His
goodness, and produces through His power.

56. Now this connection or adaptation of all created

MONADOLOGY 13

things with each, and of each with all the rest, means that
each simple substance has relations which express all the
others, and that consequently it is a perpetual living mirror
of the universe.

57. And just as the same town, when looked at from
different sides, appears quite different and is, as it were,
multiplied in perspective, so also it happens that because of
the infinite number of simple substances, it is as if there were
as many different universes, which are however but different
perspective representations of a single universe from the
different points of view of each monad.

58. And this is the means of obtaining as much variety as
possible, but with the greatest order possible ; that is to say,
it is the means of obtaining as much perfection as possible.

59. Further it is this hypothesis alone (which I venture to
regard as proved) which properly exalts the greatness of God.
This M. Bayle recognized, when in his Dictionary (in the
article 'Rorarius') he made objections, in which he was even
inclined to believe that I attributed too much to God, and
more than is possible. But he could not advance any reason
why this universal harmony, which causes each substance
exactly to express all the others through the relations which
it has with them, should be impossible.

60. Moreover, it is evident from what I have just said that
there are a priori reasons why things could not be otherwise
than they are: namely, because God in regulating the whole
had regard to each part, and particularly to each monad.
The nature of the monad is representative, and consequently
nothing can limit it to representing a part of things only,
although it is true that its representation is confused as
regards the detail of the whole universe and can only be
distinct as regards a small part of things; that is to say as
regards those which are either the nearest or the largest in
relation to each of the monads ; otherwise each monad would
be a divinity. It is not in the object, but in the modification

14 MONADOLOGY

of the knowledge of the object, that monads are limited. In
a confused way they all go towards the infinite, or towards
the whole; but they are limited and distinguished from one
another by the degrees of their distinct perceptions.

61. And in this the compounds symbolize the simples.
For as the whole is a plenum, which means that the whole
of matter is connected, and as in a plenum every movement
has some effect on distant bodies in proportion to their dis-
tance, so that each body not only is affected by those which
touch it, and is in some way sensitive to whatever happens
to them, but also by means of them is sensitive to those which
touch the first bodies by which it is itself directly touched;
it follows that this communication stretches out indefinitely.
Consequently every body is sensitive to everything which is
happening in the universe, so much so that one who saw
everything could read in each body what is happening every-
where, and even what has happened or what will happen, by
observing in the present the things that are distant in time
as well as in space; av^irvoia iravra, as Hippocrates said.
But a soul can only read in itself what is distinctly represented
there; it is unable to develop all at once all the things that
are folded within it, for they stretch to infinity.

62. Thus although each created monad represents the
whole universe, it represents more distinctly the body which
is particularly affected by it, and whose entelechy it is: and
as this body expresses the whole universe by the connection
of all matter in the plenum, the soul represents the whole
universe also in representing the body which belongs to it in
a particular way.

63. The body belonging to a monad, which is that body's
entelechy or soul, constitutes together with the entelechy
what may be called a living thing, and with the soul what is
called an animal. Now this body of a living thing or animal
is always organic; for since every monad is in its way a mirror
of the universe, and since the universe is regulated in a

MONADOLOGY 15

perfect order, there must also be an order in that which
represents it, that is to say in the perceptions of the soul,
and consequently in the body, according to which order the
universe is represented therein.

64. Thus each organic body of a living thing is a kind
of divine machine, or natural automaton, which infinitely
surpasses all artificial automata. Because a machine, which
is made by the art of man, is not a machine in each of its parts ;
for example, the tooth of a metal wheel has parts which as
far as we are concerned are not artificial and which have
about them nothing of the character of a machine, in relation
to the use for which the wheel was intended. But the
machines of nature, that is to say living bodies, are still
machines in the least of their parts ad infinitum. This it is
which makes the difference between nature and art, that is
to say between Divine art and ours.

65. And the Author of nature was enabled to practise this
divine and infinitely marvellous artifice, because each portion
of matter is not only infinitely divisible, as the ancients
recognized, but is also actually subdivided without limit,
each part into further parts, of which each one has some
motion of its own: otherwise it would be impossible for each
portion of matter to express the whole universe.

66. Whence it is evident that there is a world of created
beings living things, animals, entelechies, and souls in the
least part of matter.

67. Each portion of matter may be conceived as a garden
full of plants, and as a pond full of fish. But every branch
of each plant, every member of each animal, and every drop
of their liquid parts is itself likewise a similar garden or pond.

68. And although the earth and the air interspersed be-
tween the plants in the garden, or the water interspersed
between the fish in the pond, are neither plant nor fish, yet
they still contain them, though most usually of a subtlety
which renders them imperceptible to us.

D95

16 MONADOLOGY

69. Thus there is nothing waste, nothing sterile, nothing
dead in the universe; no chaos, no confusions, save in appear-
ance. We might compare this to the appearance of a pond
in the distance, where we can see the confused movement and
swarming of the fish, without distinguishing the fish them-
selves.

70. Thus we see that each living body has a dominant
entelechy, which in the case of an animal is the soul, but the
members of this living body are full of other living things,
plants and animals, of which each has in turn its dominant
entelechy or soul.

71. But we must not imagine, as some have done who
have misunderstood my view, that each soul has a mass or
portion of matter appropriate or attached to itself for ever,
and that it consequently possesses other inferior living things,
for ever destined to its service. For all bodies are in a
perpetual flux like rivers, and parts are passing in and out
of them continually.

72. Thus the soul only changes its body bit by bit and by
degrees, so that it is never despoiled of all its organs all
together; in animals there is often metamorphosis, but never
metempsychosis, nor transmigration of souls: neither are
there any entirely separate souls, nor superhuman spirits
without bodies. God alone is entirely detached from body.

73. It is because of this also that there is never, strictly
speaking, absolute generation nor perfect death, consisting
in the separation of the soul. And what we call generation
is a development and a growth, while what we call death is an
envelopment and a diminution.

74. Philosophers have been much embarrassed over the
origin of forms, entelechies or souls. But to-day when
exact researches on plants, insects, and animals have revealed
the fact that the organic bodies of nature are never produced
from a chaos or from putrefaction, but always from seeds,
wherein there was certainly some preformationj we conclude

MONADOLOGY 17

not only that the organic body was already present before
conception, but also that there was a soul in this body; that,
in a word, the animal itself was present, and that by means
of conception it was merely prepared for a great transforma-
tion, so as to become an animal of another kind. We even
see something of this kind apart from birth, as when worms
become flies, and caterpillars become butterflies.

75. The animals, of which some are raised by means of
conception to the rank of the larger animals, may be called
spermatic-, but those among them which remain in their own
kind (and they are the greater number) are born, multiply,
and are destroyed like the large animals; and there is only a
small number of elect ones who pass to a wider sphere.

76. But this is only half the truth. And so I judged that
if the animal never begins naturally, neither does it end
naturally; and that not only will there be no birth, but also
no complete destruction, no death, strictly speaking. And
these reasonings, which are a posteriori and derived from
experience, agree perfectly with the principles I previously
deduced a priori.

77. Thus one may say that not only is the soul (the mirror
of an indestructible universe) itself indestructible, but so also
is the animal itself, although its machine may often perish in
part, and cast off or put on particular organic integuments.

78. These principles provide me with a way of explaining
naturally the union, or rather the conformity, of the soul and
the organic body. The soul follows its own laws, and the
body its own likewise, and they accord by virtue of the
harmony pre-established among all substances, since they are
all representations of one and the same universe.

79. Souls act according to the laws of final causes by
appetitions, ends, and means. Bodies act according to the
laws of efficient causes by motions. And the two kingdoms,
of efficient and of final causes, are in harmony with one
another.

i8 MONADOLOGY

80. Descartes recognized that souls cannot give force to
bodies because there is always the same quantity of force in
matter. He believed, however, that the soul could change
the direction of bodies. But this is because in his day the
law of nature was not known which affirms the conservation
of the same total direction in matter. Had he noticed this,
he would have stumbled upon my system of Pre-established
Harmony.

8 1 . Under this system, bodies act as though, per tmposstbtle,
there were no souls: and souls act as if there were no bodies,
and both act as if each influenced the other.

82. As for minds or rational souls, although I find that
what I have just been saying is at bottom true of all living
beings and animals (that is to say that the animal and the
soul only begin with the world and do not come to an end
any more than the world comes to an end), yet rational
animals are peculiar in this, that their little spermatic
animals, so long as they are that merely, have only ordinary
or sensitive souls; but as soon as those which are, so to speak,
elect arrive by an actual conception at human nature, then
their sensitive souls are raised to the rank of reason and to
the prerogative of minds.

83. Among other differences which exist between ordinary
souls and minds, some of which I have already pointed out,
there is also this, that souls in general are the living mirrors
or images of the universe of created things, whereas minds
are also images of the Divinity Himself, or the Author of
nature, capable of knowing the system of the universe, and
of imitating something of it by architectonic patterns, each
mind being as it were a little divinity in its own department.

84. This it is which renders minds capable of entering
into a kind of society with God, and makes His relation to
them not only that of an inventor to his machine (which is
God's relation to the rest of created things) but also that of a
prince to his subjects, and even of a father to his children.

MONADOLOGY 19

85. From this it is easy to conclude that the assemblage
of all minds must make up the City of God, that is to say
the most perfect possible state under the most perfect of
monarchs.

86. This City of God, this truly universal monarchy, is a
moral world in the natural world, and is the most exalted
and the most divine of God's works, and in it truly consists
His glory, since He could not be glorified if His greatness and
goodness were not known and wondered at by minds: it is
also in relation to this divine City that He may properly be
said to have goodness, whereas His wisdom and power are
manifested everywhere.

87. As we have established above a perfect harmony
between two natural kingdoms, the one of efficient and the
other of final causes, we ought here also to point out another
harmony between the physical kingdom of nature and the
moral kingdom of grace; that is to say between God as
Architect of the machine of the universe, and God as
Monarch of the divine City of Minds.

88. This harmony means that things conduce to grace by
the very ways of nature, and that this globe, for example,
must be destroyed and repaired by natural ways at the times
demanded by the government of minds for the chastisement
of some and the reward of others.

89. It can further be said that God as Architect satisfies
God as Lawgiver in everything, and that thus sins carry their
punishment with them by the order of nature, and by virtue
of the mechanical structure of things itself; and that in the
same way noble actions will attract their rewards by ways
which are mechanical as far as bodies are concerned, although
this cannot and should not always happen immediately.

90. Finally, under this perfect government there will be no
good action without reward, no evil action without punish-
ment, and everything must turn out for the good of the
righteous, of those, that is, who are not dissatisfied in this

20 MONADOLOGY

great State, who trust in Providence when they have done
their duty, and who love and imitate fittingly the Author of
all good, delighting in the consideration of His perfections
after the manner of true pure love, which makes us take
pleasure in the happiness of the beloved. This it is which
makes the wise and virtuous work for whatever seems to
conform with the presumptive or antecedent will of God, and
yet leaves them satisfied with what God in fact causes to
happen by His secret will, which is consequent and decisive,
recognizing as they do that if we could sufficiently understand
the order of the universe, we should find that it surpasses the
desires of the most wise, and that it is impossible to make it
better than it is, not only for the whole in general, but also
for ourselves in particular, if we are attached as we should be
to the Author of the whole, not merely as to the Architect and
efficient Cause of our being, but also as to our Master and the
final Cause which must constitute the whole end of our will,
and which alone can constitute our happiness.

PRINCIPLES OF NATURE AND OF GRACE, FOUNDED
ON REASON. 1714

1. Substance is a being capable of action. It is simple or
compound. Simple substance is that which has no parts.
Compound substance is the combination of simple substances
or monads. Monas is a Greek work which signifies unity or
that which is one. Compounds or bodies are pluralities, and
simple substances that is lives, souls, minds are unities.
There must necessarily be simple substances everywhere,
because without simple substances there could be no com-
pounds; consequently the whole of nature is full of life.

2. Monads, having no parts, cannot be made or unmade.
They can neither begin nor end naturally, and consequently
they last as long as the universe, which will be changed but
not destroyed. They cannot have shapes, otherwise they
would have parts. Thus one monad, in itself and at a par-
ticular moment, can only be distinguished from another by
internal qualities and activities, which can be nothing else
but its perceptions (that is to say, the representations in the
simple of the compound or of that which is outside) and its
appetitions (that is to say, its tendencies to pass from one
perception to another), which are the principle of change.
For the simplicity of substance does not preclude the pos-
sibility of a multiplicity of modifications, which indeed
necessarily exist together in the same simple substance, and
these modifications must consist in the variety of the relations
of the simple substance to things which are outside. Just
as in a centre or point, in itself perfectly simple, are found an
infinite number of angles formed by the lines which meet
there.

21

22 PRINCIPLES

3. All nature is a plenum. Everywhere there are simple
substances, effectively separated from one another by actions
of their own which are continually altering their relations;
and each simple substance or distinct monad, which forms
the centre of a compound substance (e.g. of an animal) and
the principle of its oneness, is surrounded by a mass composed
of an infinite number of other monads which constitute the
body belonging to this central monad; corresponding to the
affections of its body it represents, as in a kind of centre, the
things which are outside of it. And this body is organic, when
it forms a kind of automaton or natural machine, which is a
machine not only as a whole but also in its smallest observ-
able parts. And since because the world is a plenum every-
thing is connected together, and each body acts on every other
body more or less according to the distance, and is affected by
it by reaction, it follows that every monad is a mirror that is
alive or endowed with inner activity, is representative of the
universe from its own point of view, and is as much regulated
as the universe itself. The perceptions in the monad spring
from one another according to the laws of the appetites or
the final causes of good, and evil, which consist in the observable
perceptions, regulated or unregulated in the same way as
the changes of the bodies and the phenomena outside spring
from one another according to the laws of efficient causes,
that is to say of motions. Thus there is a perfect harmony
between the perceptions of the monad and the motions of the
bodies, pre-established at the outset between the system of
efficient causes and the system of final causes. Herein
consists the concord and the physical union of the soul and
the body, which exists without the one being able to change
the laws of the other.

4. Each monad, together with a particular body, makes a
living substance. Thus there is not only life everywhere,
joined to members or organs, but there are also infinite
degrees of it in the monads, some of them more or less

PRINCIPLES 23

dominating over others. But when the monad has its
organs adjusted in such a way that by means of them the
impressions they receive, and consequently the perceptions
which represent them, are distinguished and heightened (as,
for example, when by means of the shape of the humours of
the eye rays of light are concentrated and act with more
force), this may amount to sensation, that is to say, to a per-
ception accompanied by memory a perception, to wit, of
which a certain echo long remains to make itself heard on
occasion. Such a living being is called an animal, as its
monad is called a soul. And when this soul is raised to the
level of reason, it is something more sublime, and is reckoned
as a mind, as will be explained later. It is true that animals
are sometimes in the condition of simple living beings and
their souls in the condition of simple monads, to wit, when
their perceptions are not sufficiently distinguished to be
remembered, as occurs in a deep dreamless sleep or in a swoon.
But perceptions which have become entirely confused must
necessarily be developed again in animals, for reasons I
shall give below (12). Thus it is well to distinguish be-
tween perception which is the inner state of the monad
representing external things, and apperception, which is
consciousness, or the reflective knowledge of this inner state,
and which is not given to all souls, nor at all times to the
same soul. It is for want of this distinction that the
Cartesians made the mistake of taking no account of per-
ceptions which are not apperceived, as common people take
no account of insensible bodies. It is this also which made
these same Cartesians believe that minds alone are monads,
and that there are no souls in animals, and still less other
principles of life. And while, in thus denying sensations to
animals, they have gone against the common opinion of men
too much, so they have, on the other hand, taken too much
account of the prejudices of the vulgar, in confusing a long
stupor, which arises from a great confusion of perceptions,

24 PRINCIPLES

with actual death, in which all perception would cease. This
teaching of theirs has confirmed the ill-founded belief in the
destruction of some souls, and the pernicious view of certain
people, supposed to be free-thinkers, who have denied the
immortality of ours.

5. There is a connection between the perceptions of
animals, which bears some resemblance to reason: but it is
based only on the memory of facts or effects, and not at all
on the knowledge of causes. Thus a dog runs away from
the stick with which he has been beaten, because memory
represents to him the pain which was caused by that stick.
And men, in so far as they are empiricists, that is to say
in three-fourths of their actions, only act like brutes. For
example, we expect that day will dawn tomorrow, because
we have always experienced it to be so; it is only the
astronomer who foresees it by reason, and even this pre-
diction will ultimately fail when the cause of daylight, which
is not eternal, ceases. But true reasoning depends on
necessary or eternal truths (like the truths of logic, numbers,
and geometry) which make the connection of ideas indubit-
able, and the sequences inevitable. Animals in which such
sequences cannot be observed are called brutes; but those
which know these necessary truths are called rational
animals, and their souls are called minds. These souls are
capable of performing acts of reflection, and of considering
what is called self, substance, soul, mind those things and
truths, in short, which are immaterial. It is this which
makes us capable of understanding science or demonstrative
knowledge.

6. The researches of the moderns have taught us, and it is
approved by reason, that the living things whose organs we
know, that is to say plants and animals, do not come from
putrefaction or chaos as the ancients believed, but from
pre-f armed seeds, and consequently from the transformation
of pre-existing living things. There are little animals in the

PRINCIPLES 25

seeds of the large ones, which by means of conception assume
a new vesture, which they appropriate, and which enables
them to be nourished and to grow, so as to pass on to a wider
stage, and propagate the large animal. It is true that the
souls of human spermatic animals are not rational and only
become so when through conception these animals are
destined for human nature. And as animals are usually not
born completely in conception or generation, so neither do
they perish completely in what we call death, for it is reason-
able that what does not begin naturally should not come to
an end in the order of nature either. Thus, casting off their
masks or their rags, they merely return to a more subtle scene,
on which, however, they can be as sensible and as well ordered
as on the greater one. And what has just been said of large
animals occurs also in the generation and death of these
spermatic animals themselves; that is to say, they have grown
from other smaller spermatic animals, in comparison with
which they can be reckoned large; for everything in nature
proceeds ad infinitum. Thus not only souls but animals also
are ingenerable and imperishable: they are only developed,
enveloped, reclad, stripped, transformed; souls never leave
the whole of their body, and do not pass from one body to
another which is entirely new to them. Thus there is no
metempsychosis, but there is metamorphosis. Animals change,
take on and put off parts only: in nutrition this takes place
bit by bit, and by small insensible parts, but continually,
while in conception and death when much is acquired or
lost all at one time the change takes place rarely, but all at
once and in a way that can be noticed.

7. Up till now we have spoken as physicists merely; now
we must rise to metaphysics, making use of the great principle,
commonly but little employed, which holds that nothing takes
place without sufficient reason, that is to say that nothing
happens without its being possible for one who has enough
knowledge of things to give a reason sufficient to determine

36 PRINCIPLES

why it is thus and not otherwise. This principle having been
laid down, the first question we are entitled to ask will be:
Why is there something rather than nothing ? For 'nothing' is
simpler and easier than 'something'. Further, supposing
that things must exist, it must be possible to give a reason
why they must exist just as they do and not otherwise.

8. Now this sufficient reason of the existence of the
universe cannot be found in the series of contingent things,
that is to say, of bodies and of their representations in souls.
For since matter is in itself indifferent to motion or to rest,
and to one motion rather than another, it cannot itself
contain the reason of motion, still less of a particular motion.
And although the present motion which is in matter arises
from the one before it, and this in its turn from the one
before that, we are no further on however far we go; for the
same question always remains. Thus the sufficient reason,
which needs no further reason, must be outside this series of
contingent things, and must lie in a substance which is the
cause of this series, or which is a being that bears the reason
of its existence within itself; otherwise we should still not
have a sufficient reason, with which we could stop. And
this final reason of things is called God.

9. This simple primary substance must include eminently
the perfections which are contained in the derivative sub-
stances which are its effects. Thus it will have perfect power,
knowledge, and will; that is to say, it will have omnipotence,
omniscience, and supreme goodness. And as justice, taken in
a very general sense, is nothing other than goodness in con-
formity with wisdom, there must clearly also be supreme
justice in God. Reason, which has made things exist
through Him, makes them also depend on Him in their
existence and operation; and they are continually receiving
from Him that which endows them with some perfection;
but any imperfection which they retain comes from the
essential and original limitations of the created thing.

PRINCIPLES 27

10. It follows from the supreme perfection of God that in
producing the universe He chose the best possible plan, con-
taining the greatest variety together with the greatest order;
the best arranged situation, place; and time, the greatest
effect produced by the simplest means; the most power, the
most knowledge, the most happiness and goodness in created
things of which the universe admitted. For as all possible
things have a claim to existence in the understanding of
God in proportion to their perfections, the result of all these
claims must be the most perfect actual world which is
possible. Otherwise it would not be possible to explain
why things have happened as they have rather than
otherwise.

11. The supreme wisdom of God has made Him choose
especially the laws of motion, which are the best adjusted
and the most fitted to abstract and metaphysical reasons.
According to them there is always conserved the same
quantity of total and absolute force or activity; the same
quantity of relative force or reaction; the same quantity,
finally, of force of direction. Moreover the activity is
always equal to the reaction, aud the whole effect is always
equivalent to its full cause. It is surprising that those
laws of motion discovered in our day, some of which I
have myself discovered, cannot be explained merely by the
consideration of efficient causes or of matter. For I have
found that it is necessary to have recourse to final causes,
and that these laws do not depend on the principle of necessity
as do the truths of logic, arithmetic, and geometry, but on
the principle of fitness, that is to say on the choice of wisdom.
Thus it is one of the most effective and sensible proofs of the
existence of God for those who are able to go deeply into
these matters.

12. It follows, further, from the perfection of the Supreme
Author, that not only is the order of the whole universe the
most perfect possible, but also that each living mirror which

28 PRINCIPLES

represents the universe from its own point of view, that is
to say each monody each substantial centre, must have its
perceptions and appetites regulated in the best way which is
compatible with all the rest. From which it follows that
sotdsj that is to say the most dominant monads, or rather
animals themselves, cannot fail to wake up from the state of
stupor in which they may be placed by death or by some
other accident.

13. For everything is regulated in things once for all with
as much order and agreement as possible, since supreme
wisdom and goodness cannot act without perfect harmony:
the present is big with the future, what is to come could be
read in the past, what is distant expressed in what is near.
The beauty of the universe could be learnt in each soul,
could one unravel all its folds which develop perceptibly
only with time. But as each distinct perception of the
soul includes an infinite number of confused perceptions
which embrace all the universe, the soul itself does not know
the things which it perceives, except in so far as it has per-
ceptions of them which are distinct and heightened: and it
has perfection in proportion to its distinct perceptions. Each
soul knows the infinite, knows everything, but confusedly.
Just as when I am walking along the shore of the sea and
hear the great noise it makes, though I hear the separate
sounds of each wave of which the total sound is made up, I
do not discriminate them one from another; so our confused
perceptions are the result of the impressions which the whole
universe makes on us. It is the same with each monad.
God alone has a distinct knowledge of everything, for He is
the source of everything. It has been very well said that as
a centre He is everywhere; but His circumference is nowhere,
since everything is present to Him immediately, without
being removed from this centre.

14. As regards the rational soul or mind, there is in it
something more than in monads, or even in simple souls.

PRINCIPLES 29

It is not only a mirror of the universe of created things, but
also an image of the Deity. The mind not only has a percep-
tion of the works of God, but is even capable of producing
something like them, though on a small scale. For, not to
mention the wonders of dreams, in which we invent without
effort (but also without will) things we could only discover
after much thinking when awake, our soul is architectonic
in its voluntary activities also, and, discovering the sciences
in accordance with which God had regulated things (pondere,
mensura, numero, 1 etc.), it imitates in its own sphere, and in
the little world in which it is allowed to act, what God per-
forms in the great world.

15. For this reason all minds, whether of men or super-
human spirits, entering as they do by virtue of reason and
the eternal verities into a kind of society with God, are
members of the City of God, that is to say of the most
perfect state, formed and governed by the greatest and
best of monarchs: where there is no crime without punish-
ment, no good action without proportionate reward, and
finally as much virtue and happiness as is possible; and this,
not by any derangement of nature, as if what God has in
store for the soul might disturb the laws of the body, but by
the actual order of natural things, by virtue of the harmony
pre-established from all time between the realms of nature
and of grace, between God as Architect and God as Monarch,
in such a way that nature itself leads to grace, and grace
perfects nature in making use of it.

16. Thus although reason cannot teach us the details of
the great future, which are reserved for revelation, we can
rest assured by this same reason that things are accomplished
in a manner which exceeds our desires. Since, too, God is
the most perfect and the most happy and consequently the
most lovable of substances, and since pure true love consists
in the state which causes pleasure to be felt in the perfections

1 'by weight, measure, number', etc.

30 PRINCIPLES

and happiness of the beloved, this love ought to give us the
greatest pleasure of which a man is capable, when God is
the object of it.

17. It is easy to love Him as we ought if we know Him as
I have described. For although God is not sensible to our
external senses, He is none the less very lovable and gives
great pleasure. We see how much pleasure men derive from
honours, although they do not consist of qualities that appear
to the external senses. Martyrs and fanatics (although the
affection of the latter is ill regulated) show of what the
pleasure of the mind is capable: and what is more, even the
pleasures of the senses are in the last resort intellectual
pleasures, confusedly known. Music charms us although its
beauty only consists in the harmony of numbers, and in the
account which we do not notice, but which the soul none the
less takes, of the beating or vibration of sounding bodies,
which meet one another at certain intervals. The pleasures
which the eye finds in proportions are of the same kind, and
those caused by the other senses amount to much the same
thing, although we may not be able to explain it so dis-
tinctly.

18. It may even be affirmed that love of God gives us
here and now a foretaste of future felicity. And although
it is disinterested, it constitutes of itself our greatest good and
interest, even though we may not seek them in it, and con-
sider only the pleasure which it gives without regard to the
utility it produces; for it gives us a perfect confidence in
the goodness of our Author and Master, which produces a
true tranquillity of mind, not as in the Stoics, who resolutely
force themselves to patience, but by a present contentment,
which further assures us a future happiness. And apart
from the present pleasure, nothing could be more useful for
the future, for the love of God also fulfils our hopes, and
leads us in the way of supreme happiness, because in virtue
of the perfect order established in the universe, everything

PRINCIPLES 31

is done in the best possible way, as much for the general
good as also for the greatest particular good of those who
believe in it, and who are satisfied by the Divine government:
which cannot fail to be the case with those who know how to
love the Source of all good. It is true that supreme happiness
(with whatever beatific vision, or knowledge of God, it may
be accompanied) can never be complete because God, being
infinite, cannot be entirely known. Thus our happiness will
never consist, and ought not to consist, in a complete enjoy-
ment, in which there would be nothing left to desire, and
which would make our mind stupid, but in a perpetual
progress to new pleasures and new perfections.

E95

ON THE ULTIMATE ORIGINATION OF THINGS
23 NOVEMBER 1697

BESIDES the world or aggregate of finite things we find a
certain Unity which is dominant, not only in the sense in
which the soul is dominant in me, or rather in which the self
or / is dominant in my body, but also in a much more exalted
manner. For the dominant Unity of the universe not only
rules the world, but also constructs or makes it; and it is
higher than the world and, if I may so put it, extramundane;
it is thus the ultimate reason of things. Now neither in any
one single thing, nor in the whole aggregate and series of
things, can there be found the sufficient reason of existence.
Let us suppose the book of the elements of geometry to have
been eternal, one copy always having been written down
from an earlier one; it is evident that, even though a reason
can be given for the present book out of a past one, never-
theless out of any number of books taken in order going
backwards we shall never come upon a full reason; though we
might well always wonder why there should have been such
books from all time why there were books at all, and why
they were written in this manner. What is true of the books
is true also of the different states of the world; for what
follows is in some way copied from what precedes (even
though there are certain laws of change). And so, however
far you go back to earlier states, you will never find in those
states a full reason why there should be any world rather
than none, and why it should be such as it is.

Indeed, even if you suppose the world eternal, as you will
still be supposing nothing but a succession of states and will
not in any of them find a sufficient reason, nor however many

3*

THE ORIGINATION OF THINGS 33

states you assume will you advance one step towards giving
a reason, it is evident that the reason must be sought else-
where. For in things which are eternal, though there may
be no cause, nevertheless there must be known a reason;
which reason in things that are permanent is necessity
itself or essence, but in the series of changeable things (if
this be supposed to be an eternal succession from an earlier
to a later) it will be, as will be presently understood, the
prevailing of inclinations, in a sphere where reasons do not
necessitate (by an absolute or metaphysical necessity, in
which the contrary implies a contradiction), but incline.
From this it is evident that even by supposing the world
to be eternal we cannot escape the ultimate, extra-mundane
reason of things, or God.

The reasons of the world then lie in something extra-
mundane, different from the chain of states, or series of
things, whose aggregate constitutes the world. And so we
must pass from physical or hypothetical necessity, which
determines the subsequent things of the world by the earlier,
to something which is of absolute or metaphysical necessity,
for which itself no reason can be given. For the present
world is necessary physically or hypothetically, but not
absolutely or metaphysically. In other words, when once it
is determined that it shall be such and such, it follows that
such and such things will come into being. Since then the
ultimate root must be in something which is of metaphysical
necessity, and since there is no reason of any existent thing
except in an existent thing, it follows that there must exist
some one Being of metaphysical necessity, that is, from whose
essence existence springs; and so there must exist something
different from the plurality of beings, that is the world, which,
as we have allowed and have shown, is not of metaphysical
necessity.

Let me explain a little more distinctly how out of truths
that are eternal or essential or metaphysical there arise

34 THE ORIGINATION OF THINGS

truths that are temporal, contingent, or physical. First we
must notice, from the very fact that something exists rather
than nothing, that there is in things that are possible, or in
possibility of essence itself, a certain need for existence, or
(if I may so put it) a claim to exist; and, to put it bluntly,
that essence in itself tends towards existence. From this it
further follows that all things which are possible, or express
essence or possible reality, tend by equal right towards
existence in proportion to the quantity of essence or reality
which they include, or in proportion to the stage of perfection
which belongs to them; for perfection is nothing else than
quantity of essence.

Hence it is seen to be most evident that out of the infinite
combination of possibles, and the infinite possible series, that
one exists by whose means the greatest possible amount of
essence or possibility is brought into existence. There is
always, I take it, to be found in things a principle of de-
termination which turns on considerations of greatest and
least; namely, that the greatest effect should be produced
with (if I may so put it) the least expenditure. And the
time, the place, or (in a word) the receptivity or capacity of
the world, may here be taken to be the expenditure or
ground, on which a building is to be raised as fittingly as
possible, while the variety of forms is in accordance with the
fitness of the building and with the number and elegance
of its rooms. It is very much like what happens in certain
games, in which all the spaces on the board have to be filled
in according to certain rules: unless you show some ingenuity
you will find yourself at the end kept out of certain refractory
spaces, and thereby compelled to leave empty more spaces
than you need have done, and more than you wished. There
is, however, a definite formula by which the greatest possible
success in filling the spaces is easily obtained. For instance,
if we suppose ourselves told to construct a triangle, there
being no other principle of determination, the result is that

THE ORIGINATION OF THINGS 35

we draw an equilateral triangle; and if we are required to go
from one point to another, and nothing further is added to
determine the way, we shall choose the path that is easiest or
shortest. Similarly, once it has been granted that a being is
better than a not-being, that is, that there is a reason why
something should exist rather than nothing, or that transition
from possibility to actuality is to take place, then, even if
nothing further is determined, the consequence is that there
exists as much as is possible in view of the capacity of time
and place (or of the possible order of existing) in very much
the same way as tiles are fitted together so as to put in as
many as possible within the given area.

From this it is now wonderfully clear how in the very
origination of things a certain Divine mathematics or
metaphysical mechanics is employed, and how the greatest
quantity comes to be determined. It is on this principle that
of all the angles the right angle is the determined angle in
geometry, and that liquids when placed in heterogeneous
media form themselves into the most capacious shape, that
is, the spherical; but the best instance of all is that in com-
mon mechanics itself, when several heavy bodies are operating
against one another, the result is that movement which
secures the greatest descent on the whole. For just as all
things that are possible with equal right tend towards
existence in proportion to their reality, so in the same way
all weights with equal right tend towards descent in pro-
portion to their gravity; and just as in the latter case there
results a motion involving the greatest possible descent of
the heavy bodies, so in the former case there results a world
involving the greatest production of things that are possible.

Thus we now have physical necessity based on metaphysical
necessity. For although the world is not metaphysically
necessary, so that its contrary would imply a contradiction
or logical absurdity, nevertheless it is necessary physically,
that is, determined in such a way that its contrary would

36 THE ORIGINATION OF THINGS

imply imperfection or moral absurdity. And as possibility
is the principle of essence, so perfection or degree of essence
(which makes the largest number of things compossible) is
the principle of existence. This makes it evident at the
same time how there can be freedom in the Author of the
world, although He does everything determinately, because
He acts from the principle of wisdom or perfection. In-
difference arises from ignorance, and the wiser a man is, the
more is he determined to that action which is most perfect.

But (you will say) this comparison of a certain metaphysical
determining mechanism with the physical mechanism of
heavy bodies, elegant though it may appear, has nevertheless
this fault: there really exist heavy bodies acting against one
another, but possibilities or essences prior to or beyond
existence are imaginary or fictitious, and therefore it is of
no use to seek in them the reason of existence. I answer,
that neither the essences nor the truths about them which
are known as eternal truths, are fictitious; they exist (if I may
so put it) in a certain region of ideas, that is, in God Himself,
the fount of all essence and of the existence of everything.
That this is no merely arbitrary assertion is shown by the
very existence of the actual series of things. For since in the
series a reason cannot be found, as I have shown above, but
must be sought in metaphysical necessities or eternal truths;
since, too, existent things cannot come into being except
from existent things, as I have explained previously; it
follows that eternal truths must have their existence in some
subject which is absolutely or metaphysically necessary,
that is in God, through whom these truths, which would
otherwise be imaginary, are (to use a barbarous but ex-
pressive word) realized. 1

And indeed in actual fact we find that everything in the
world takes place in accordance with the laws of the eternal
truths, not only geometrical but also metaphysical laws;
1 The word realisentur is a barbarism in Latin.

THE ORIGINATION OF THINGS 37

that is, not only according to material necessities, but also
according to formal necessities. This is not only true
in general, in regard to the reason (which I have just ex-
plained) why the world should exist rather than not, and why
it should exist just as it is rather than otherwise (this reason
is certainly to be found in the tendency of what is possible
towards existence); but more than this, if we come down to
details, we see the marvellous way in which metaphysical
laws hold sway in the whole of nature the laws of cause, of
potency, of activity, and how they prevail even over the
purely geometrical laws of matter themselves, as I found
to my great wonder when I was giving an account of the
laws of motion; so much so, indeed, that though from my
early youth, when I was more of a materialist, I had defended
the law of the geometric composition of forces, I was finally
forced to abandon it, as I have explained at greater length
elsewhere.

Here then we have the ultimate reason of the reality both
of essences and of existences in a Unity, which must certainly
be greater, higher, and prior to the world itself, since through
it alone not only the existent things, which the world contains,
but also the things that are possible have their reality. It
cannot be found except in one single source, because of the
interconnection of all these things with one another. It is
evident that from this source existent things are continually
issuing and being produced, and have been produced, since
it is not clear why one state of the world rather than another,
yesterday's state rather than today's, should flow from the
world itself. It is also evident how God acts not only
physically but also freely; and how there lies in Him not only
the efficient but also the final cause; and how from Him
proceeds the reason not only of the greatness or potency
that there is in the mechanism of the universe as now
established, but also of the goodness or wisdom involved in
the establishing of it.

38 THE ORIGINATION OF THINGS

In case someone may think that moral perfection or good-
ness is here being confused with metaphysical perfection or
greatness, and may admit the latter while denying the
former, it should be pointed out that it follows from what has
been said not only that the world is the most perfect physic-
ally, or, if you prefer it, metaphysically, or in other words
that that series of things will be forthcoming which in actual
fact affords the greatest quantity of reality, but also that
the world should be the most perfect morally, because true
moral perfection is physical perfection in minds themselves.
Hence the world is not only the most wonderful machine,
but also in regard to minds it is the best commonwealth, by
whose means there is bestowed on minds the greatest possible
amount of felicity or joyfulness; and it is in this that their
physical perfection consists.

But, you will say, we find in the world the very opposite
of this. Often the worst of sufferings fall upon the best men;
the innocent (I speak not only of the brutes, but of men also)
are afflicted, and are slain even with tortures; indeed the
world, especially if we look at the government of the human
race, seems rather a confused chaos than an affair ordained
by some supreme wisdom. So it appears at first sight, I
allow: but on deeper examination it must be agreed that the
opposite is the case. It is evident a priori from those very
principles which I have adduced that without doubt there is
secured in the world the highest perfection that there could
possibly be of all things, and therefore of minds.

And indeed it is unreasonable, as the lawyers say, to
give a judgment without inspecting the whole law. We have
knowledge of a tiny part of that eternity which stretches out
immeasurably. For how small a thing is the memory of the
few thousand years which history hands down to us! And
yet out of so little experience we rashly make judgments
about the immeasurable and the eternal; just as men who
had been born and bred in prison or in the subterranean

THE ORIGINATION OF THINGS 39

salt-mines of Sarmatia might think that there was no other
light in the world than the treacherous flicker of torches,
which was hardly sufficient to guide their footsteps. Look
at the most lovely picture, and then cover it up, leaving
uncovered only a tiny scrap of it. What else will you see
there, even if you look as closely as possible, and the more so
as you look from nearer and nearer at hand, but a kind of
confused medley of colours, without selection, without art!
And yet when you remove the covering, and look upon the
whole picture from the proper place, you will see that what
previously seemed to you to have been aimlessly smeared
on the canvas was in fact accomplished with the highest
art by the author of the work. What happens to the eyes in
painting is equally experienced by the ears in music. The
great composers frequently mingle discords with harmonious
chords so that the listener may be stimulated and pricked as
it were, and may become eager to know what is going to
happen; presently when all is restored to order he feels so
much the more content. In the same way we may take
pleasure in small dangers, or in the experience of ills, from
the very sense or proof they give us of our own power or
felicity. Or again at the spectacle of rope-walking or sword-
dancing we are delighted by the very element of fear that is
involved, and we ourselves in play with children hold them
as if we were going to throw them out of the window, and
half let them go in very much the same way as the ape
carried Christian, King of Denmark, when he was still an
infant wrapped in long clothes, to the edge of the roof, and
then, when everybody was in terror, turned it into jest and
put him back into his cradle safe and sound. On the same
principle it has an insipid effect if we always eat sweet things;
sharp, acid, and even bitter things should be mixed in to
stimulate the taste. He who has not tasted what is bitter
has not earned what is sweet, nor will he appreciate it. This
is the very law of enjoyment, that positive pleasure does not

40 THE ORIGINATION OF THINGS

come from an even course; such things produce weariness,
and make men dull, not joyful.

What I have said, however, about the possibility of a part
being disturbed without upsetting the harmony of the whole
must not be interpreted to mean that no account is taken
of the parts; or that it is sufficient for the whole world to be
completed at all points, even though it should turn out that
the human race was wretched, and that there was in the uni-
verse no care for justice and no account was taken of us as is
maintained by some people whose judgment about the sum of
things is ill-grounded. For the truth is that, just as in a well
regulated commonwealth care is taken that as far as possible
things shall be to the interest of the individual, in the same
way the universe would not be sufficiently perfect unless, as
far as can be done without upsetting the universal harmony,
the good of individual people is considered. Of this there
could be established no better measure than the very law of
justice itself, which dictates that each should have a part
in the perfection of the universe and in his own happiness in
proportion to his own virtue and to the extent to which his
will is directed tgwards the common good ; by which is fulfilled
what we call the charity and love of God, in which alone,
according to the judgment of wise theologians also, stands the
whole force and power of the Christian religion. Nor ought
it to seem remarkable that all this deference should be paid to
minds in the universe, since they bear the closest resemblance
to the image of the supreme Author, and their relation to Him
is not that of machines to their artificer (like the rest of the
world) but rather that of citizens to their prince; moreover
they will endure as long as the universe itself, and they, in some
manner, express and concentrate the whole in themselves; so
that it might be said that minds are whole parts.

As for the afflictions of men, and especially of good men,
we must hold ourselves assured that they contribute to the
greater good of those who suffer them; and this is true not

THE ORIGINATION OF THINGS 41

only theologically, but physically also, just as a grain of
wheat cast into the earth must suffer before it bears fruit.
And in general it is true to say that afflictions are for the
time being evil, but in effect good, since they are short cuts
to a greater perfection. Similarly in physics the liquids
which ferment slowly are also more slowly purified, whereas
those in which there is a more violent disturbance throw off
the foreign parts with greater force and so more quickly
become pure. You might fairly say that this is a case of
taking a step back in order to make a stronger leap forward
(reader pour mteux sauter). These things must be allowed
to be not only pleasant and consoling, but also most true.
Indeed in general I hold that there is nothing truer than
happiness, and nothing happier and sweeter than truth.

Further, we realize that there is a perpetual and a most
free progress of the whole universe in fulfilment of the
universal beauty and perfection of the works of God, so that
it is always advancing towards a greater development. Thus,
even now a great part of our earth has received cultivation,
and will receive it more and more. And though it is true
that there are times when some parts of it go back again to
virgin forest, or are destroyed again and oppressed, this must
be understood in the same sense as I just now interpreted
the meaning of affliction, namely, that this very destruction
and oppression contributes to achieve something greater, so
that in some way we receive profit from our very loss.

To the objection that may perhaps be offered that if this
were so the world would long ago have become a paradise,
the answer is at hand: although many substances have
already come to great perfection, yet owing to the infinite
divisibility of what is continuous, there always remain in
the abyss of things parts that are asleep, and these need to
be awakened and to be driven forward into something
greater and better in a word, to a better development.
Hence this progress does not ever come to an end.

PART II

THE DEVELOPMENT OF LEIBNIZ'S
PHILOSOPHY

LETTER TO FOUCHER. 1 1676

I AGREE with you that it is important to examine our pre-
suppositions, thoroughly and once for all, in order to establish
something solid. For I hold that it is only when we can prove
all that we bring forward that we perfectly understand the
thing under consideration. I know that the common herd
take little pleasure in these researches, but I know also that
the common herd take little pains thoroughly to understand
things. Your scheme, as I understand it, is to examine the
truths which assert that there is something outside us. In
this you appear to be very just, for thus you grant us all the
truths which are hypothetical, and which assert not that
there is something outside us, but only what would happen
if there were. Thus at the outset we save arithmetic,
geometry and a great number of metaphysical, physical, and
moral propositions, whose convenient expression depends on
definitions arbitrarily chosen, and whose truth depends on
axioms which I am accustomed to call identical; as for
instance, that two contradictories cannot both exist, that a
thing at one and the same time is what it is for instance,
it is as big as it is, equal to itself, like itself, etc.

Now although you do not enter ex professo* into the
examination of hypothetical propositions, I am nevertheless
of opinion that it should be done, and that none should be
admitted that have not been absolutely proved and resolved
into identicals.

As regards those truths which deal with what is in fact

1 Simon Foucher (1644-96), a Canon of Dijon, who professed
philosophical scepticism. Cf. pp. 109-28.

9 i.e. it is no part of your professed purpose to enter . . .

45

46 LETTER TO FOUCHER

outside us, this is the subject with which your inquiries are
primarily concerned. Now in the first place it cannot be
denied that the very truth of hypothetical propositions
themselves is something which is outside us and which does
not depend on us. For all these hypothetical propositions
assert what would or would not be, granting something
or its contrary; and consequently they assure us that the
supposition at the same time of two things that agree, or
that a thing is possible or impossible, necessary or unneces-
sary, and also this possibility, impossibility, or necessity
(for the necessity of one thing is the impossibility of its
contrary), are none of them chimeras of our own making;
since all we do is to recognize them in spite of ourselves and
in a constant manner. Thus of all things which actually are,
the possibility itself or impossibility of being is the first.
Now this possibility or necessity forms or composes what are
called essences or natures, and the truths which we are
accustomed to call eternal; and we are right so to call them,
for nothing is so eternal as what is necessary. Thus the
nature of the circle with its properties is something which
exists and is eternal: that is to say there is some constant
cause outside us which makes all those who think about it
carefully discover the same thing, and not merely that their
thoughts agree with one another; this might be attributed
simply to the nature of the human mind, but for the fact
that phenomena or experiences confirm them whenever some
appearance of a circle strikes our senses. And these phe-
nomena necessarily have some cause outside us.

But though the existence of necessities comes first of all in
itself and in the order of nature, I agree none the less that
it is not the first in the order of our knowledge. For you see
that in order to prove its existence I have taken for granted
that we think and that we have sensations. Here then are
two absolute general truths, truths that is to say which
treat of the actual existence of things: the one that we think,

LETTER TO FOUCHER 47

the other that there is a great variety in our thoughts. From
the first it follows that we are, from the other it follows that
there is something other than us; something other, that is to
say, than that which thinks, which is the cause of the variety
of our appearances. Now the one of these two truths is as
incontestable and as independent as the other; and through
fastening on the first only in the order of his meditations, M.
Descartes failed to reach the perfection which he had aimed
at. If he had exactly followed what I call thefilum medi-
tandi, 1 I think that he would have brought to completion
first philosophy? But the greatest genius in the world is
unable to force matters, and we must of necessity enter by
the gates provided by nature if we are not to go astray.
Moreover, one man alone cannot do everything at the outset;
and for my part when I consider all the fine things M. Des-
cartes has said, and said by himself, I marvel rather at what
he has done than that there is something that he failed to do.
I admit that I have not yet been able to read his writings
with all the care I intend to devote to them, and my friends
are aware that it has so happened that I read almost all the
recent philosophers before him. Bacon and Gassendi were
the first to fall into my hands ; their familiar and easy style
was more suited to a man desirous of reading everything.
It is true that I often glanced at Galileo and Descartes, but
as I have only recently become a geometrician, I was soon
put off by their manner of writing, which necessitated
serious thought. And personally, although I have always
taken pleasure in meditations of my own, I have always
found it difficult to read books which cannot be understood
without much thought; for in following one's own meditations
one follows a certain natural bent, and gains profit and
pleasure at the same time, whereas one is terribly put out at
having to follow the meditations of another. I always liked

l lit. 'the thread of thinking', i.e. his actual train of thought.

1 i.e. metaphysics.
F95

48 LETTER TO FOUCHER

books which, while containing some fine thoughts, could be
read straight through without stopping, for they gave rise
in me to ideas which I followed at fancy, and pursued as the
spirit moved me. This also prevented me from reading
books on geometry, and I readily admit that I have not yet
been able to make myself read Euclid in any different way
from that in which one generally reads histories. I have
learnt from experience that this method is in general a good
one, but I have also learnt none the less that an exception
must be made in the case of some authors, such as Plato and
Aristotle among the ancient philosophers, and Galileo and M
Descartes among those of our day. Still, such knowledge as I
have of M. Descartes's metaphysical and physical meditations
has been almost entirely derived from reading a number of
books written in a rather more familiar style which expound
his opinions. And it may be that I have not yet properly
understood him. None the less, in so far as I myself have
glanced at his work, I seem to myself at least to get a glimpse
of what he has not done, nor attempted to do; and this is
among other things, to resolve all our presuppositions. For
this reason I am accustomed to commend all those who
examined the least truth thoroughly; for I know that it is a
great thing to understand a thing perfectly, however small
and easy it may seem. This is the way to go well ahead
and to set up finally the art of discovery which depends on
a knowledge (though it must be distinct and perfect) of the
easiest things. And for this reason I do not condemn the
design of M. de Roberval, who wished to prove everything in
geometry, even including certain axioms. I admit that we
must not try to force others to be so exact, but I think it is
well to force ourselves.

I return to the truths which come first for our purpose
among those which assure us that there is something outside
us; that is to say, that we think, and that there is a great
variety in our thoughts. Now this variety of thoughts

LETTER TO FOUCHER 49

cannot come from that which thinks, since one single thing
cannot itself be the cause of the changes which are in it.
For everything remains in the state in which it is if there is
nothing to change it: and since it is not of itself determined
to have certain changes rather than others, we could not
begin to attribute to it any variety, without saying something
for which we admit there is no reason, which is absurd. And
even if we sought to maintain that there is no beginning to
our thoughts, besides the fact that we should be obliged to
assert that each of us has existed from all eternity, we should
still not escape the difficulty; for we would still be obliged to
admit that there is no reason for this variety which has
existed in our thoughts from all eternity, since there is
nothing in us which determines us to this thought rather
than to another. Thus there must be some cause outside
us for the variety of our thoughts. And as we agree that
there are some subordinate causes of this variety, which
nevertheless need a cause themselves, we have thereby
established some particular beings or substances, whose
actions we can recognize, that is to say, such that we conceive
that from a change in them follows some change in us. And
so we advance by great strides to the construction of what
we call matter and body.

But at this point you are right to hold us up a little, and to
renew the pleas of the Academy of old. For at bottom, all
our experiences assure us of two things only, namely that
there is a connection in our appearances which gives us a
means of successfully predicting future appearances; and
secondly that this connection must have a constant cause.
But from all this it does not strictly follow that there is
matter or that there are bodies, but only that there is some-
thing which presents us with appearances which follow
properly on one another. For if an invisible power were to
delight in giving us dreams properly connected with our
preceding life, and in conformity with one another, could we

50 LETTER TO FOUCHER

distinguish them from realities except after awakening? Now
what is it that prevents the course of our life being one long
well-arranged dream, about which we could be undeceived in
an instant ? And I do not see that this power would therefore
be imperfect, as M. Descartes asserts, besides the fact that
its imperfection is not under discussion. For it might
be some subordinate power, or some superhuman spirit who
was able to take a hand, I know not why, in our affairs, and
who had at least as much power over someone, as that caliph
who had a drunken man carried into his place, and there made
him taste of the paradise of Mahomet when he was awakened,
until he was once more drunk and in a condition to be taken
back to the place from which he had been brought. When this
man returned to his senses, he naturally took for a vision
what seemed to him irreconcilable with the course of his life,
and retailed to the people maxims and revelations which he
believed he had learnt in this supposed paradise; and this
was what the caliph desired. Now since a reality has passed
for a vision, what prevents a vision from passing for a reality?
It is true that the more we see a connection in what happens
to us, the more we are confirmed in the opinion that there is
reality in our appearances; and it is true also that the more
nearly we examine appearances, the better connected we find
them to be, as microscopes and other ways of making ex-
periments show us. This perpetual agreement gives us great
assurance; but after all it will be no more than a moral
assurance until somebody discovers a priori the origin of the
world which we see, and probes in the depths of its essence
to find the reason why things are as they seem. When that
is done, it will be proved that what appears to us is a reality,
and that it is impossible that we should ever be disabused
about it. But I think that this would be very like the
beatific vision, and that it is difficult to pretend to such
vision in the state in which we are. Still we learn from this
how confused the knowledge which we commonly have of

LETTER TO FOUCHER 51

body and of matter must be, since we think that we are
assured that they exist, and then find in the last analysis
that we may be mistaken.

And this confirms M. Descartes's beautiful thought con-
cerning the proof of the distinction between body and soul,
since it is possible to cast doubt on the one, without question-
ing the other. For if there were nothing but appearances or
dreams, we should be no less assured of the existence of that
which thinks, as is very well said by M. Descartes; and I
myself add that we could still prove just as well the existence
of God, by methods different from those employed by M.
Descartes, and which, in my view, take us further. For we
have no need whatever to suppose a Being who will guarantee
that we shall not be deceived, since it lies in our power to
undeceive ourselves about many things, and at least about
the most important. I hope, sir, that your meditations on
this subject will have all the success you desire; but to that
end it is a good thing to proceed in order and to establish
propositions. This is the way to gain ground and to pro-
gress with certainty. I think that you would oblige the
public further by publishing from time to time chosen
passages from the Academy, and especially from Plato; for
I know that there are to be found in them some things that
are more beautiful and sounder than is ordinarily thought.

CORRESPONDENCE WITH ARNAULD
To Landgraf Ernst von Hessen-Reinfels. i/n Feb. 1686

BEING recently at a place where for several days I had
nothing to do, I composed a small Discourse on Metaphysics,
about which I should be very glad to have the opinion of
M. Arnauld. 1 For the questions of grace, of the relations of
God with His creatures, of the nature of miracles, the cause
of sin and the origin of evil, the immortality of the soul,
ideas, etc., are touched upon in a manner which seems to
provide new opportunities for throwing light on very great
difficulties. I enclose herewith a summary of the articles
contained in it, as I have not yet had time to make a fair
copy. I beg Your Serene Highness to have this summary
sent to him, and to ask him to consider it somewhat and
express his opinion; for as he excels equally in theology and
in philosophy, in learning and in the power of thought, I can
think of no one more fitted than he to judge of it. I should
very much appreciate having a critic as exact, as enlightened,
and as reasonable as M. Arnauld, being myself as ready as
any man in the world to yield to reason. Perhaps M.
Arnauld will find this little matter not altogether unworthy
of his consideration, especially as he has been much occupied
in examining these questions. If he finds any obscurity, I
will explain myself sincerely and frankly; and if he finds me
worthy of his instruction, I will see to it that he has reason
to be not ill satisfied with me. I beg Your Serene Highness

1 Antoine Arnauld (1612-94), known as 'the great Arnauld';
a distinguished theologian, philosopher, and mathematician.
He defended the Jansenists against the Jesuits.

52

LEIBNIZ AND ARNAULD 53

to attach this to the summary which I am sending for him,
and to send both on to M. Arnauld.

SUMMARY OF THE 'DISCOURSE ON METAPHYSICS'

1. Of Divine perfection, and that God does everything in
the most desirable manner.

2. Against those who maintain that there is no goodness
in the works of God; or rather that the rules of goodness and
of beauty are arbitrary.

3. Against those who think that God might have done
better.

4. That love of God demands that we should be com-
pletely satisfied with and should acquiesce in all that He does.

5. Wherein the rules of perfection of the Divine conduct
consist, and that the simplicity of the means is exactly
balanced by the richness of the effects.

6. That God does nothing which is out of order, and that
it is not even possible to imagine events which are not
regular.

7. That miracles are in conformity with the general order,
although they go against subordinate maxims. Concerning
what God wills or permits, and concerning general and
particular will.

8. In order to distinguish God's activities from those of
created beings, an explanation is offered of wherein consists
the notion of an individual substance.

9. That each single substance expresses the whole universe
in its own way, and that in its notion are included all the
events which will happen to it with all their circumstances,
and the whole series of things outside it.

10. That the theory regarding substantial forms has
something in it, but that these forms do not change anything
in phenomena, and must not be used to explain particular
effects.

54 LEIBNIZ AND ARNAULD

11. That the meditations of the theologians and of the
philosophers known as Schoolmen are not wholly to be
despised. 1

12. That the notions which depend upon extension include
an imaginary element, and cannot constitute the substance
of body.

13. As the individual notion of each person includes once
and for all everything that will ever happen to him, in it can
be seen the a priori proofs, or reasons of the truth of every
event, or why one thing has happened rather than another.
But these truths, although they are assured, are none the
less contingent, since they are based on the free choice of
God and of created beings. It is true that there are always
reasons for their choice, but these reasons incline without
necessitating.

14. God produces different substances, according to the
different views which He has of the universe; and by the
intervention of God the proper nature of each substance is
such that what happens to one corresponds to what happens
to all the others, without their acting immediately one upon
another.

15. The action of one finite substance upon another
consists only in an increase of the degree of its expression
together with a decrease of that of the other, inasmuch as
God has so formed them in advance that they shall agree
together.

16. The extraordinary intervention of God is included in
what is expressed by our essence; for this expression extends
to everything. But it surpasses the forces of our nature or
of our distinct expression, which is finite and follows certain
subordinate maxims.

17. An example of a subordinate maxim of the law of

1 This section of the Discourse itself is purely general. Leibniz
does not mention any instances of truths to be found in the
Schoolmen. He mentions St. Thomas with special honour.

LEIBNIZ AND ARNAULD 55

nature, in which it is shown that God always regularly
conserves the same force, but not the same quantity of
motion, contrary to the teaching of the Cartesians and some
others.

18. The distinction between force and quantity of motion
is important, among other things as snowing that it is
necessary to have recourse to metaphysical considerations
distinct from extension in order to explain the phenomena
of bodies.

19. The value of final causes in physics.

20. A memorable passage from Socrates in Plato's Phaedo l
against a too materialistic philosophy.

21. If the laws of mechanics depended on geometry alone
without metaphysics, phenomena would be quite other
than they are.

22. A reconciliation of two methods, one of which proceeds
by final causes and the other by efficient causes; which will
satisfy both those who explain nature mechanically and those
who have recourse to incorporeal natures.

23. Returning to immaterial substances, an explanation is
offered how God acts on the understanding of minds, and
whether we always have an idea of what we are thinking about.

24. Of the nature of knowledge, clear or obscure, distinct or
confused, adequate or inadequate, intuitive or supposititious;
of nominal, real, causal, and essential definition.

25. In what cases our knowledge goes always with the
contemplation of the idea.

26. We have within us all the ideas there are; and of
Platonic reminiscence.

27. Of how our soul may be compared to a tabula rasa, 2
and of how our notions come from the senses.

1 In this section of the Discourse itself a gap is left, into which
Leibniz evidently intended to transcribe the passage from Plato.

1 ' a blank tablet ', i.e. a wax writing tablet with no impressions
on it, or (to use the language of Locke) a piece of white paper.
Cf. p. 143.

56 LEIBNIZ AND ARNAULD

28. God is the sole immediate object of our perceptions,
which exists outside of us, and He alone is our light.

29. Nevertheless we think immediately by our own ideas,
and not by those of God.

30. How God inclines our soul without necessitating it;
that we have no right to complain; that we must not ask
why Judas sins, since that free action is included in his
notion, but only why Judas the sinner is admitted into
existence preferably to some other possible people. Of
original imperfection or limitation before sin, and of the
degrees of grace.

31. Of the motives of elective choice, of faith foreseen, of
mean science, 1 of absolute decree; and that everything is
reduced to the reason why God chose to admit into existence
such and such a possible person, whose notion includes the
particular succession of acts of grace and of free actions.
This at once puts an end to all difficulties.

32. Value of these principles in matters of piety and religion.

33. Explanation of the intercourse between the soul and
the body, which has been regarded as inexplicable or as
miraculous, and of the origin of confused perceptions.

34. Of the difference between minds and other substances,
souls or substantial forms. And that the immortality we
desire requires memory.

35. Excellence of minds: that God considers them above
other created things; that minds express God rather than
the world, and that other simple substances express the world
rather than God.

36. God is the Monarch of the most perfect commonwealth
composed of all minds, and the happiness of the City of God
is His chief design.

1 Science moyenne. In the corresponding section of the
Discourse itself there is no reference to it whatever. From the
Theodicy it appears to refer to knowledge of ' conditional events ',
which Leibniz regards as intermediate between knowledge of
possibilities and knowledge of actual facts.

LEIBNIZ AND ARNAULD 57

37. Jesus Christ has revealed to mankind the mystery and
the admirable laws of the Kingdom of Heaven and the
greatness of the supreme happiness which God prepares for
those who love Him.

To Landgraf Ernst von Hessen-Rheinfels. 12 April 1686

... I said in the thirteenth article of my Summary that
the individual notion of each person includes once for all
everything which will ever happen to him. He l draws from
this the consequence that everything which happens to a
person, and even to the whole human race, must happen by
a more than fatalistic necessity as if notions or previsions
rendered things necessary, and as if a free action could not be
contained in the notion or perfect vision which God has of
the person to whom it will belong. He adds that perhaps
I shall find nothing to trouble me in the conclusion he draws.
And yet I had expressly protested in the very same article
that I did not admit such a conclusion. So either he must
doubt my sincerity, for which I have given him no reason,
or else he has not sufficiently examined the view he is re-
jecting. Still I will not reproach him for this, as it seems I
have a right to do, since I bear in mind that he was writing
at a time when some indisposition did not allow him the
free use of all his mind, as is witnessed by his letter itself. 2

1 Arnauld.

2 Arnauld had complained of a bad cold in the previous letter;
and he had added, ' All that I can now do is to say in two words
to Your Highness that I find in these meditations so many things
which frighten me, and which, unless I am much mistaken, all
mankind will find so shocking, that I do not see that any purpose
would be served by a piece of writing which will manifestly be
rejected by the whole world. . . . Would it not be better for him
to abandon these metaphysical speculations, which can be of no
value either to him or to any one else, and to apply himself
earnestly to the matter which is of the greatest importance of
all to him, namely to assure his own salvation by returning to
the Church . . . ?' Arnauld afterwards sincerely apologized
for this rather off-hand treatment of Leibniz.

58 LEIBNIZ AND ARNAULD

And I wish to have it known how much respect I feel for
him.

If that is the case, he says (namely that the individual
notion of each person includes once for all everything which
will ever happen to him), God was not free to create all that has
happened to the human race and all that will ever happen by a
more than fatalistic necessity (there is some fault in the copy
but I think I have succeeded in restoring it as above). For
the individual notion of Adam included his having so many
children, and the individual notion of each of these children
included everything that they would do and all the children they
would have, and so on. God had, then, no more freedom in all
this, supposing that He had once willed to create, than He had
freedom not to create a being capable of thought^ These last
words should strictly contain the proof of the consequence;
but it is very clear that they confuse necessitatem ex hypothesi a
with absolute necessity. A distinction has always been
drawn between what God is absolutely free to do and what
He is obliged to do by virtue of certain resolutions already
taken (and He does not take any without previous regard to
all). It is not worthy of God to conceive of Him (under
pretext of vindicating His liberty), in the manner of some
Socinians, as being like a human being who takes his resolu-
tions in consideration of circumstances, and as now being no
longer free to create what He considers good, if His earliest
resolutions in regard to Adam or others already include a
relation to everything already connected with their posterity.
On the contrary every one is agreed that God has ordered

1 Arnauld's own letter reads as follows: God had then no more
freedom in all this, supposing He had once willed to create Adam
than to argue that God was free, supposing He had once willed to create
me, not to create a being capable of thought. (This sentence is some-
what confused, but it sufficiently indicates the line of argument.
It will be seen that the whole passage is loosely and confusedly
written, as if Leibniz were in some difficulties to state his view.)
1 i.e. that which necessarily follows from a given hypothesis.

LEIBNIZ AND ARNAULD 59

from all eternity the whole succession of the universe, without
its diminishing His freedom in any way.

It is evident also that this objection separates off from one
another acts of will on the part of God, which are really
connected together. We must not consider God's will to
create a particular Adam as separated from all His other
acts of will in regard to the children of Adam and all the
human race; as if God first made the decision to create Adam
without any relation to his posterity, and none the less by
that decision, according to my view, deprived Himself of the
freedom to create the posterity of Adam, as seemed to Him
good. This would be a strange way of reasoning. Rather
we should think of God as choosing, not just any Adam
vaguely, but a particular Adam, of whom there exists among
the possible beings in the ideas of God a perfect representa-
tion, accompanied by certain individual circumstances, and
possessing among other predicates that of having in the
course of time certain posterity; we must think of God, I say,
as choosing him with an eye to his posterity, and so as
equally at the same time choosing the one and the other. I
cannot see what harm there is in that. If He acted otherwise,
He would not be acting like God. Let me suggest a com-
parison. A wise prince, when he chooses a general whose
connections he knows, in effect chooses at the same time a
number of colonels and captains, whom he well knows the
general will appoint, and whom he will not want to reject for
reasons of prudence: yet they do not in any way destroy his
absolute power, nor his freedom. The case is exactly the
same with God for much stronger reasons. Therefore, to be
exact, we must recognize in God a certain more general and
comprehensive will, in which He has an eye to the whole
order of the universe, since the universe is like a whole which
God apprehends in a single view. This will virtually includes
all the other acts of will about what is to come into this
universe, and among the rest it includes that of creating a

60 LEIBNIZ AND ARNAULD

particular Adam, who is connected with the whole succession
of his posterity, which God has also chosen as it is. We
might even say that these particular acts of willing the
details only differ from the willing of the whole general
purpose in a simple respect, very much as the situation of a
town considered from a particular point of view differs from
its ground-plan. 1 For these particular acts of will all of
them express the whole universe in the same way as each
situation expresses the town. In fact the wiser a man is,
the less does he have detached acts of will, and the more do
his views and his acts of will become comprehensive and
connected. And each particular act of will includes a relation
to all the others, so that they are as well harmonized as
possible. Far from finding in all this something shocking, I
should have thought that the contrary would destroy the
perfection of God. And in my opinion it must have been a
matter of great difficulty, or else of great prejudice, to find in
opinions so innocent, or rather so reasonable, an occasion for
such strange exaggerations as those which were sent to Your
Serene Highness.

Moreover, some slight consideration of what I have said
will show that it is evident ex ter minis? For by the individual
notion of Adam I undoubtedly mean a perfect representation
of a particular Adam, with given individual conditions and
distinguished thereby from an infinity of other possible
persons very much like him, but yet different from him
(just as every ellipse is different from the circle, however
closely it approaches to it). God preferred him to all these
others, because it pleased Him to choose just this particular
order of the universe; and all that follows from this decision
of His is necessary only by a hypothetical necessity, and in

1 Plan g&omltval: a plan drawn to scale, showing the true
measurements in proportion, i.e. having no regard to perspective.
Cf. p. 84.

'from the terms themselves', i.e. from an analysis of the
meaning of the terms.

LEIBNIZ AND ARNAULD 61

no way derogates from the freedom of God nor from that of
created minds. There is one possible Adam whose posterity
is such and such, and an infinity of others whose posterity
would be different; is it not the case that these possible
Adams (if I may so speak of them) are different from one
another, and that God has chosen only one of them, who is
exactly our Adam? There are so many reasons which prove
the impossibility, not to say the absurdity and even impiety,
of the contrary, that I think that at bottom all men are of
the same opinion, when they give a little thought to what
they say. Perhaps, too, if M. Arnauld had not held about
me the prejudiced view with which he started, he would not
have found my propositions so strange and would not have
drawn from them the consequences which he did. ...

To Landgraf Ernst von Hessen-Rheinfels. 12 April 1686

. . . Every man who acts wisely considers all the circumstances
and connections of the decision he is taking, and the more so
in proportion to his capacity. Will God, who sees every-
thing perfectly and with a single glance, fail to have taken
His decision in conformity with everything He sees? Can
He have chosen a particular Adam without considering
and deciding as well everything which has any connection
with him? Consequently it is ridiculous to say that this free
decision of God's takes away His liberty. Otherwise, to be
free it would be necessary to be for ever undecided. . . .

Remarks on M. Arnauld' s letter about my proposition that the
individual notion of each person includes once for all everything
that will ever happen to him. May 1686

... He admits in good faith that he understood my opinion
to be that everything that happens to an individual can be
deduced from his individual notion in the same way and with
the same necessity as the properties of a sphere can be

62 LEIBNIZ AND ARNAULD

deduced from its specific notion or definition; and that he
supposed I had been considering the notion of the individual
in itself, without regarding the manner in which it exists in
the understanding or will of God. For (he says) it appears to
me that we are not accustomed to consider the specific notion of
a sphere in relation to what is represented in the Divine under-
standing, but in relation to what it is in itself, and I supposed
it was the same with the individual notion of each person;
but he adds that, now that he knows what my view is, that is
enough to enable him to grant it sufficiently to try and find out
whether it removes all the difficulties; a matter of which he is
still in doubt.

I see that M. Arnauld has not remembered, or at least has
not concerned himself about, the opinion of the Cartesians,
who hold that God establishes by His will the eternal truths,
like those regarding the properties of the sphere. But as I
am not of their opinion any more than M. Arnauld, I will
simply explain why I hold that we must philosophize
differently about the notion of an individual substance than
we do about the specific notion of a sphere. This is because
the notion of a species includes eternal or necessary truths
only, whereas the notion of an individual includes sub
ratione possibilitatis l what is fact, or what is related to the
existence of things and to time; and consequently it depends
on certain free decisions of God, considered as possible.
For truths of fact or of existence depend upon God's decisions.
Further, the notion of a sphere in general is incomplete or
abstract; that is to say we only consider the essence of a
sphere in general or in theory, without regard to individual
circumstances. Consequently the notion does not include
in any way what is required for the existence of a certain
sphere. But the notion of the sphere which Archimedes

1 'considered under the head of possibility'; i.e. that which is,
as a matter of fact, an actual fact is considered, not as actual
fact, but as possible.

LEIBNIZ AND ARNAULD 63

had placed upon his tomb is a fully worked out notion, and is
bound to include everything which belongs to the object of
that form. This is why in the case of individual considera-
tions, or considerations of practice, quae versantur circa
singularia, 1 besides the form of the sphere there enter in the
matter of which it is made, the place, the time, and the other
circumstances, which by a continual chain would in the end
cover the whole series of the universe, if it were possible to
follow out all that these notions include. For the notion of
this piece of matter, of which the sphere is made, involves
all the changes which have ever happened or will ever happen
to it. According to my view, every individual substance
always contains traces of all that has ever happened to it and
marks of all that ever will ever happen to it for all time.
What I have just said may suffice to explain my train of
thought.

... As regards the objection that possibles are independent of
the decisions of God, I grant that they are so of actual de-
cisions (though the Cartesians do not agree with this); but
I hold that possible individual notions include a number
of possible free decisions. For example, if this world were
possible only, the individual notion of any body in this world,
which includes certain movements as possible, would include
our laws of motion (which are free decisions of God), but it
would include them as possible only. For as there is an
infinity of possible worlds, there is also an infinity of laws,
some proper to one world, others to another; and each
possible individual of any world includes in its notion the
laws of its world.
The same thing can be said of miracles or the extraordinary

1 ' which are concerned with individuals', what is individual
being opposed to what is general. The point of introducing these
Latin phrases is, of course, that Leibniz wishes to indicate that
he is following orthodox logical doctrine of the Schools.

64 LEIBNIZ AND ARNAULD

operations of God, which none the less belong within the
general order; they are in conformity with the principal
designs of God, and consequently are included in the notion
of this universe, which is a result of those designs. Just as
the idea of a building results from the ends and designs of the
builder, so the idea or notion of this world is a result of these
designs of God, considered as possible. For everything must
be explained by its cause; and the cause of the universe is the
ends of God. Now each individual substance, according to
my view, expresses the whole universe from a certain point
of view, and consequently it also expresses the said miracles.
All this must be understood of the general order, of the designs
of God, of the series of the universe, of individual substance,
and of miracles, whether they are taken in their actual state
or are considered stib ratione posstbtlttatts. 1 For another
possible world will have all those things too in their own
manner, though the designs of our own world have been
preferred.

It will be seen too, from what I have just said about the
designs of God and about the primary laws, that this uni-
verse has a certain principal or primary notion, of which
particular happenings are merely consequences without,
however, eliminating freedom and contingency, to which
certainty is in no way inimical, since the certainty of events
is partly based on free actions. ... To speak exactly, it should
be said that it is not so much because God decided to create
this Adam that he decided on all the rest; the truth is rather
that both His decision regarding Adam and His decision
about other particular things are a consequence of His
decision in regard to the whole universe and of the principal
designs which determine its primary notion and establish in
it this general inviolable order, with which everything is in
conformity, without even excepting miracles, which are
without doubt in conformity with the principal designs of
1 i.e. not as facts, but as possibilities

LEIBNIZ AND ARNAULD 65

God, although they do not always observe the particular
maxims which are called laws of nature.

I said before that the supposition from which all human
events can be deduced is not simply that of the creation of a
vague Adam, but that of the creation of a particular Adam
determined in all his circumstances and chosen from among
an infinity of possible Adams. This has given M. Arnauld
occasion to object, not without reason, that it is as impossible
to conceive of several Adams, taking Adam as a unique
nature, as it would be to conceive of several Is. I agree;
but I must add that in speaking of several Adams, I was
not taking Adam as a determined individual. I must
explain myself; this is what I meant. When in considering
Adam we consider a part of his predicates, as for instance
that he is the first man, set in a pleasure garden, from out of
whose side God took a woman, and similar things conceived
stib ratione generalitatis l (i.e. without naming Eve, Paradise,
or other circumstances which fix individuality), and we give
the name Adam to the person to whom these predicates are
attributed, all this is not sufficient to determine the indi-
vidual; for there might be an infinity of Adams, that is to say
of possible persons, different from one another, to whom all
that is appropriate. Far from disagreeing with what M.
Arnauld says against such a plurality of one and the same
individual, I used the same argument myself to make it clear
that the nature of an individual must be complete and deter-
mined. I am indeed entirely persuaded of what St. Thomas
had already taught in regard to intelligences, and which I hold
to be of general application, namely that it is not possible
that there should be two individuals entirely alike, or differing
solo numero. 2 We must not then conceive of a vague Adam,
that is to say a person to whom certain of Adam's attributes

1 i.e. considered in general, as opposed to considered in respect
of its unique, individual character
fl numerically only.'

66 LEIBNIZ AND ARNAULD

belong, when it is a question of determining whether all
human happenings follow from the supposition of him; we
must attribute to him a notion so complete that everything
that can be attributed to him can be deduced from it. Now
there is no room for doubt but that God could form such a
notion of him, or rather that He finds it ready made in the
country of possibles, that is, in His understanding.

It follows also that he would not have been our Adam, but
another, if he had had different events; for nothing prevents
us from saying that he would be another. Therefore he is
another. It appears evident to us that this square of marble
brought from Genoa would have been in all respects the
same, if it had been left there, because our senses only make
us judge superficially; but at bottom, because of the inter-
connection of things, the whole universe with all its parts
would be quite different, and would have been a quite
different universe from the beginning, if the least thing
went differently from the way it does go. It is not for this
reason that .all that happens is necessary; it is because
everything that happens is certain after God made choice
of this possible universe, whose notion contains this series of
things. I hope that what I am going to say will make even
M. Arnauld agree with me.

Let there be a straight line ABC representing a certain
time. And let a certain individual substance, for instance
myself, remain or exist throughout the given time. Let us
first take the 1 which exists during the time AB, and then
the / which exists during the time BC. Since then the pre-
sumption is that it is the same individual substance enduring
throughout, or rather that it is I who exist in the time AB,
being then in Paris, and that it is still I who exist in the time
BC, being then in Germany, it follows necessarily that there
is a reason which makes us say truly that we endure, that is,
that I who was in Paris am now in Germany. For if there is
no reason, we should have as much right to say that it is

LEIBNIZ AND ARNAULD 67

another person. It is true that my internal experience
convinces me a posteriori of this identicalness, but there must
be a reason a priori. Now it is not possible to find any other
except that both my attributes in the preceding time and
state and my attributes in the later time and state are
predicates of one and the same subject: insunt eidem sub-
jecto. 1 Now what is meant by saying that a predicate is in a
subject, except that the notion of the predicate is in some
way included in the notion of the subject? And since from
the time when I began to exist it was possible to say of me
truly that this or that would happen to me, it must be
acknowledged that these predicates were laws included in
the subject, or in the complete notion of me which caused me
to be called 7, which is the foundation of the interconnection
of all my different states, and which was perfectly known to
God from all eternity.

After this I think that all doubts should disappear, for
when I say that the individual notion of Adam includes
everything that will ever happen to him, I do not mean
anything other than what all the philosophers mean when
they say praedicatum inesse subjecto verae propositions?
It is true that the consequences of so evident a doctrine are
paradoxical; but that is the fault of the philosophers, who
do not follow up sufficiently the clearest notions.

I think that M. Arnauld, being as penetrating and fair-
minded as he is, will now no longer find my proposition so
strange, even if he is not yet able to approve of it entirely
(though I almost persuade myself that he will approve). I
agree with what he says so judiciously about the circum-
spection that is necessary in attempting to use the Divine
knowledge 8 to find out what we ought to discover from the

1 'they are included in the same subject'.
1 ' in a true proposition the predicate is included in the subject',
i.e. because God's knowledge is inaccessible to us as finite
intelligences. We should not suppose that we can understand

68 LEIBNIZ AND ARNAULD

notions of things. But, rightly understood, what I have
just said must be allowed, since God would only be brought
in as much as is necessary. For we should not need to
assert that God, in considering the Adam whom He is
deciding to create, sees in him everything that will happen
to him; it is enough that we can always prove that there must
be a complete notion of this Adam which contains them. For
all the predicates of Adam either depend upon other predi-
cates of the same Adam, or they do not so depend. Putting
on one side, then, those which do depend on others, we have
only to take together the primary predicates in order to form
the complete notion of Adam, which is sufficient to make it
possible to deduce from it everything which must happen to
him, as far as is necessary to give an explanation of it. It is
evident that God can invent, and even does in fact conceive,
such a notion, which is sufficient to account for all the
phenomena which belong to Adam; but it is no less evident
that it is possible in itself. It is true that we must not, unless
it is necessary, involve ourselves in the investigation of
Divine knowledge and Divine will because of the great
difficulties therein; still, we can explain all of this which we
need for our question without entering into the difficulties
mentioned by M. Arnauld for example, whether the
simplicity of God is reconcilable with the distinctions we
are obliged to make with regard to Him. It is also extremely
difficult to explain perfectly how God has a knowledge which
He might not have had, namely the knowledge of vision 1 ;
for if contingencies in the future did not exist, God would
have no vision of them. It is true that He would have
simple knowledge, which is vision, none the less, for having
joined to it His will; so that this difficulty perhaps reduces

God's knowledge, and infer from this the nature of particular
things. We must start from the notions of things which we
find in ourselves.

1 vision in the sense in which the prophets had visions.

LEIBNIZ AND ARNAULD 69

itself to such difficulty as there is about His will, that is, how
God is free to will. This is without doubt beyond us, but it
is not so necessary to understand it in order to solve our
problem.

As for the manner in which we conceive that God acts in
choosing the best among several possibles, M. Arnauld is
right in finding some obscurity there. Yet he seems to recog-
nize that we are led to conceive that there is an infinity of
possible first men, each with a great following of persons and
events, and that God chose the one who together with his
following pleased Him. All that is not as strange as it had
first appeared to him. It is true that M. Arnauld testifies
that he is very much inclined to think that substances that
are purely possible are nothing but chimeras. About this I
do not want to enter into dispute: but I hope that in spite of
that he will grant me what I need. I agree that there is no
other reality in pure possibilities but that which they have in
the Divine understanding; and from this it can be seen that
M. Arnauld himself will be obliged to fall back on the Divine
knowledge to explain them, whereas he seemed to mean just
now that they ought to be looked for in themselves. Since
I should admit also the proposition, of which M. Arnauld is
convinced and which I do not deny, namely that we do not
conceive of any possibility except through ideas which are to
be found in the things which God has created, this objection
does not affect my argument. For when I speak of possi-
bilities, I am quite satisfied that it should be possible to
form true propositions about them. For example, if there
were no perfect square in the world, we should still see that
it does not involve any contradiction. And if we absolutely
reject pure possibilities, this means that there is no con-
tingency; for if nothing is possible except what God has in
fact created, what God has created would be necessary,
supposing He had once decided to create anything.

Finally, I agree that in order to judge of the notion of

70 LEIBNIZ AND ARNAULD

an individual substance it is a good thing to consider that
which I have of myself, just as it is necessary to consider
the specific notion of a sphere in order to judge of its pro-
perties. And yet there is a considerable difference; for the
notion of me and of every other individual substance is
infinitely more extended and more difficult to understand
than a specific notion like that of a sphere, which is in-
complete only. It is not enough that I feel myself a
substance which thinks, it would be necessary to conceive
distinctly what distinguishes me from all other minds; but
of this I have only a confused experience. The result is
that, though it is easy to determine that the number of
feet in the diameter is not included in the notion of the
sphere in general, it is not so easy to determine whether the
journey which I intend to make is included in my notion;
otherwise it would be as easy for us to be prophets as to
be geometers. I am uncertain whether I shall go on the
journey; but I am not uncertain that, whether I go or not,
I shall still be the same I. It is an unreflective conviction, 1
which must not be confused with a notion or distinct appre-
hension. These things only seem to us to be undetermined
because the foreshadowings or marks which are there in
our substance are not recognizable by us. In the same
way those who take no account of anything but the senses
will treat with ridicule any one who says that the least
movement communicates itself on and on as far as matter
extends, because this could not be learnt from experience
alone; but when we consider the nature of motion and of
matter, we are convinced. It is the same here: when I
consider the confused experience I have of the individual
notion of me in particular, I take no care to perceive this
connection of events; but when I consider the general,
distinct notions which enter into the notion of me, I come

1 Prevention. There is not, I think, a sufficiently exact English
equivalent; and this cumbrous phrase seems to be unavoidable.

LEIBNIZ AND ARNAULD ;r

upon that connection. In fact, in considering the notion
that I have of every true proposition, I find that every
predicate, necessary or contingent, past, present, or future,
is contained in the notion of the subject; and I ask no more.
Indeed, I think that this will open up to us a way of
reconciliation; for I imagine that M. Arnauld felt a repug-
nance against assenting to my proposition only because he
took the connection, which I am maintaining, to be intrinsic
and necessary at the same time, whereas I hold it to be
intrinsic, but in no way necessary; and I have now suffi-
ciently explained that it is founded on free decisions and
actions. I do not mean any other connection between
subject and predicate than that which is to be found in the
most contingent truths; that is to say, there is always
something to be conceived in the subject which provides
the explanation why this predicate or this event belongs
to it, or why a particular event happened rather than not.
But the reasons of these contingent truths incline without
necessitating. It is true then that I am not able to go
on this journey, but it is certain that I shall go. This
predicate or event is not certainly connected with my other
predicates conceived incompletely or sub rattone generalitatis}-
but it is connected certainly with my complete individual
notion, since I suppose that this notion was expressly so
constructed that it might be possible to deduce from it
everything which happens to me. This notion is without
doubt a parte rei\ 2 and it properly is the notion of me, who
find myself in a number of different states, since it is this
notion alone which is capable of including them all. . , .

1 Cf. p. 65, note i.

f 'from the side of the thing itself; i.e. the notion is of
something really existing, and not of an imaginary or merely
possible object.

72 LEIBNIZ AND ARNAULD

To Arnauld. Hanover, 14 July 1686

... I agree that the connection of events, although it
is certain, is not necessary, and that it is open to me to go
or not to go on this journey; for although it is included in
my notion that I shall go, it is also included that I shall
go freely. And of all that in me which can be conceived
sub ratione generalitatis seu essentiae seu notionis specificae
sive tncompletae 1 there is nothing from which it can be
inferred that I shall go necessarily; whereas from the fact
that I am a man it can be concluded that I am capable of
thinking. Consequently, if I do not go on this journey, it
will not violate any eternal or necessary truth. Neverthe-
less, since it is certain that I shall go, there is bound to be
some connection between me, who am the subject, and the
accomplishment of the journey, which is the predicate;
semper enim notio praedicati inest stibjecto in propositione
vera* Thus if I did not go there would be a falsity which
would destroy my individual or complete notion, or that
which God conceives of me, or did conceive even before he
decided to create me. For this notion involves sub ratione
possibilitatis* existences, or truths of fact, or decisions of
God, on which facts depend. . . .

. . . You approve, sir, the interconnections of God's
decisions; you recognize as certain my principal proposi-
tion, in the sense which I gave to it in my reply. You are
simply in doubt whether I made the interconnection inde-
pendent of the free decisions of God; and this quite rightly
troubles you. But I have made it clear that according to

1 ' in general terms, or in terms of its essence or of its specific
or incomplete notion'.

1 'for in a true proposition the notion of the predicate is always
included in the subject'.

r Cf. p. 64, note.

LEIBNIZ AND ARNAULD 73

my view it depends on these decisions, and that it is not
necessary though it is intrinsic. You insisted on the diffi-
culty that would be involved in saying that if I do not go
on this journey as I am bound to do, I shall not be I; and
I explained how it may be said or may not. Finally I gave
a decisive reason, which in my opinion takes the place of
demonstration; namely, that in every affirmative true pro-
position, necessary or contingent, universal or singular, the
notion of the predicate is contained in some way in that of
the subject, praedicatum inest subjected Or else I do not
know what truth is.

Now I ask no more connection here than that which exists
a parte rei a between the terms of a true proposition; and it
is in this sense only that I say that the individual substance
includes all its events and all its denominations, even those
which are commonly called extrinsic (that is, they belong to
it only by virtue of the general interconnection of things and
because it expresses the whole universe in its own way), there
must always be some foundation of the connection of the terms of a
proposition, which foundation must lie in their notions. This
is my chief principle, on which I hold that all philosophers
ought to be agreed. And one of its corollaries is the common
axiom that nothing happens without a reason, which can
always be given to explain why the thing turned out thus
rather than otherwise, though this reason often inclines
without necessitating, a perfect indifference being a chi-
merical or incomplete supposition. It will be seen that
from the aforesaid principle I draw surprising consequences;
but this is only because people are not accustomed to thinking
out sufficiently the clearest apprehensions. . . .

You may perhaps be surprised that I deny the action of one
bodily substance on another, when it seems to be so evident.

* 'the predicate is included in the subject*.
1 Cf. p. 71, note 2.

74 LEIBNIZ AND ARNAULD

But besides the fact that others have denied it before me,
we must bear in mind that it is rather a play of the imagina-
tion than a distinct conception. If a body is a substance,
and not a mere phenomenon like the rainbow, nor an entity
united by accident or by aggregation like a heap of stones, it
cannot consist of extension; and it must necessarily be con-
ceived as something which is called substantial form, and
which corresponds in some way to a soul. I became con-
vinced of this in the end, as it were in spite of myself, after
having held a very different opinion in earlier days. Still,
approve as I may of the Schoolmen in this general and, if I
may so put it, metaphysical explanation of theirs of the
principles of bodies, I still subscribe fully to the corpuscular
theory in the explanation of particular phenomena; in this
sphere it is of no value to speak of forms or qualities. Nature
must always be explained mathematically and mechanically,
provided it is remembered that the very principles or laws of
mechanics or of force do not depend on mathematical
extension alone, but on certain metaphysical reasons. . . .

To Arnauld. Hanover, 14 July 1686

. . . Also I do not much approve of the behaviour of those
who are always appealing to their ideas, when they are at
the end of their proofs, and who misuse the principle that
every clear and distinct conception is valid. 1 I hold that we
must always look for some mark in a distinct apprehension;
and as we often think without ideas, by using ciphers (in place
of the ideas in question) whose signification we falsely suppose
ourselves to know, and make up for ourselves impossible
chimeras. I hold that the mark of a genuine idea is that its
possibility can be proved, either a priori by conceiving its
cause or reason, or a posteriori when experience teaches us

1 lit. * good '. It will be seen that later in the same paragraph
Leibniz speaks of ' a genuine idea ', and also of ' a true idea '.

LEIBNIZ AND ARNAULD 75

that it in fact exists in nature. For this reason definitions,
in my view, are real when it is known that the thing defined is
possible; otherwise they are nominal only, and should not be
trusted, since if by chance the thing defined implied a con-
tradiction, two contradictory consequences might be inferred
from one and the same definition. Hence you were abso-
lutely right to inform Fr. Malebranche and others that a
distinction must be made between true and false ideas, and
that too much rein must not be given to a man's imagination
under pretext of its being a clear and distinct intellection.

Draft of a letter to Arnauld. 28 November/ 8 December 1686

. . . The action is attributed to that substance, whose ex-
pression is more distinct, and which is called the cause. For
instance, when a body is floating in water, an infinity of
movements of the particles of the water are necessary so that
the place which the body leaves may always be filled by the
shortest way. Hence we say that the body is the cause of
these movements; because by its means we can explain
distinctly what happens. But if we examine what is physical
and real in the motion, we can as well suppose that the body
is at rest, and that everything else moves in conformity with
this hypothesis, since the whole motion is in itself nothing but
a relative thing, namely a change of situation, such that we
cannot know to what to attribute it in mathematical pre-
cision. Actually we attribute it to a body, by whose means
everything is explained distinctly. . . .

Thus in strict metaphysical precision, we have no more
reason to say that the ship causes the water to produce this
large number of circles which serve to fill up the place of the
ship, than to say that the water is caused to produce all these
circles and that it causes the ship to move accordingly. But
short of saying that God has expressly willed to produce this
large number of movements in this co-ordinated manner, we

76 LEIBNIZ AND ARNAULD

cannot give the reason for them; and as it is not reasonable to
have recourse to God in matter of detail, we fall back on the
ship, although as a matter of fact in the last analysis the
agreement of all the phenomena of the different substances
comes simply from the fact that they are all the products of
one and the same cause, namely God, who arranges that each
individual substance expresses the decision which God has
taken in regard to the whole universe.

I do not know whether the body, when the soul or sub-
stantial form is put aside, can be called a substance. It
might well be a machine, an aggregate of several substances,
so that, if I am asked what I should say de forma cadaveris x
or about a square of marble, my reply is that they are perhaps
unities per aggregattonem a like a heap of stones, and are not
substances. The same might be said of the sun, of the earth,
of machines; and with the exception of man there is no body
of which I can be assured that it is a substance rather than an
aggregate of several substances, or perhaps a phenomenon.
Nevertheless it seems to me certain that, if there are any
corporeal substances, man is not the only one; and it appears
probable that the brutes have souls, though they are without
consciousness.

Finally, although I agree that the consideration of forms
or souls is useless in particular physics, it is for all that of
importance in metaphysics. In the same way geometers
do not trouble themselves de compositione continui* and
physicists do not concern themselves whether one ball
impels another, or whether it is God.

It would be unworthy of a philosopher to admit such souls

1 'about the form of the physical, human body 1 , as dis-
tinguished of course r om the whole living being.

'by aggregation*.

'about the composition of a continuum 1 ; i.e. how that which
is continuous can have parts and yet be continuous, etc.

LEIBNIZ AND ARNAULD 77

or forms unless there were a reason for it; but without them
the fact that bodies are substances is not intelligible.

To Arnauld. Gottingen, 30 April 1687

. . . You suppose that I will not say that a body can move
itself; and so, since the soul is not the real cause of the
movement of the arm, nor is the body, the cause will there-
fore be God. But I am of a different opinion. I hold that
all that is real in the state which is called motion proceeds
as much from the corporeal substance as thought and will
proceed from the mind. Everything happens in each
substance in consequence of the first state which God gave
to it in creating it, and, extraordinary intervention apart,
His ordinary intervention consists simply in the conserva-
tion of the same substance, in conformity with its precedent
state and with the changes which it carries within it. Never-
theless, it is quite right to say that one body impels another;
that is to say that the fact is that one body never begins
to have a given tendency except when another body which
is touching it has a proportionate loss, in accordance with
the constant laws which we observe in phenomena. And
in fact, motions being real phenomena rather than entities,
a movement as phenomenon is in my mind the immediate
consequence or effect of another phenomenon, and similarly
in the minds of others. But the state of a substance is
not the immediate consequence of the state of another
particular substance. . . .

If my opinion that substance requires a true unity were
founded on a definition that I had myself made up contrary
to common usage, then the dispute would be simply one of
words. But in the first place philosophers have understood
this term in much the same manner, distinguendo uftum
per se et unum per accidens, formamque substantialem et
accidentalem, mixta imperfecta et perfecto, naturdia et

78 LEIBNIZ AND ARNAULD

artificialia. 1 In the second place, I approach the matter
from a higher ground also, and, waiving the analysis of
terms, / hold that where there are only entities by aggregation,
there will not be any real entities. For every entity by aggre-
gation presupposes entities endowed with a true unity, for
it only takes its reality from the reality of those of which it
is composed, so that it will not have any at all, if each
entity of which it is composed is itself an entity by aggre-
gation; or else it is necessary to look further for a different
foundation of its reality, which, if it is at every stage neces-
sary to go further in looking for it, can never be found.
I agree, sir, that in all corporeal nature there are nothing
but machines (which are often animated); but I do not agree
that there are nothing but aggregates of substances \ and if
there are aggregates there must also be some true substances
of which the aggregates are made up. We must then come
down to either the mathematical points, out of which some
authors compound extension, or to the atoms of Epicurus
and M. Cordemoy (which are things that you and I alike
reject), or else we must acknowledge that no reality can be
found in bodies; or finally we must recognize some substances
as having a genuine unity. I have already said in another
letter that a combination of the Grand Duke's diamond and
the Great Mogul's diamond may be called a pair of diamonds,
but that is only an entity of reason: when they are put
side by side, that will be an entity of imagination or of
perception, that is to say a phenomenon; for their contact,
their common movement, and their co-ordination to carry
out one and the same design, make no difference as regards
substantial unity. It is true that there is sometimes more,
sometimes less foundation for our supposition, when we
suppose that several things are combining to make one
1 'by distinguishing between that which is a unity of itself
and that which is a unity adventitiously, between substantial and
accidental form, and between imperfect and perfect, natural
and artificial compounds'.

LEIBNIZ AND ARNAULD 79

single thing, according as the things have more or less
connection; but this is only a way of abbreviating our
thoughts and of picturing phenomena.

It appears, too, that what constitutes the essence of an
entity by aggregation is nothing but a manner of existence
of the things of which it is composed; for example, what
constitutes the essence of an army is simply a manner of
existence of the men who compose it. This manner of
existence, then, presupposes a substance, whose essence is
not the manner of existence of a substance. Every machine,
too, presupposes some substance in the pieces of which it is
made; and there can be no plurality without true unities.
To put it shortly, I maintain as axiomatic this identical
proposition, whose differentiation can only be marked by
the accentuation namely, that that which is not truly an
entity cannot cither be truly an entity. It has always been
held that unity and entity are reciprocal things. An entity
is one thing, entities are quite another thing: but the plural
presupposes the singular, and where there is no entity still
less are there several entities. What could be more clearly
stated? I therefore thought that I might be allowed to
distinguish entities by aggregation from substances, since
such entities have their unity in our mind only; which
unity is based upon the relations or modes of genuine sub-
stances. If a machine is a substance, a circle of men holding
one another's hands will be a substance too; so will an
army, and so will every plurality of substances.

I do not mean that there is nothing substantial, or nothing
but appearance, in the things which have no genuine unity;
for I agree that they have always as much reality or sub-
stantiality as there is genuine unity in that of which they
are composed.

You object, sir, that it may perhaps be of the essence of

8o LEIBNIZ AND ARNAULD

body not to have a true unity. But in that case it will be
of the essence of body to be a phenomenon, deprived of all
reality, like an ordered dream; for phenomena themselves,
like a rainbow or a heap of stones, would be wholly imaginary,
if they were not composed of entities with a genuine unity.

You say that you do not see what leads me to admit that
there are such substantial terms, or rather corporeal sub-
stances, endowed with a genuine unity. It is because I do
not conceive of any reality at all as without genuine unity.
According to my view the notion of singular substance
involves consequences which are incompatible with its being
an entity by aggregation. I conceive of there being properties
in substance which cannot be explained by extension, shape,
and motion, besides the fact that there is no exact and fixed
shape in bodies because of the actual subdivision of the con-
tinuum ad infinitum. Moreover, motion inasmuch as it is
only a modification of extension and a change of neighbour-
hood, involves an imaginary element, so that it is not possible
to determine to which of the subjects that change it belongs,
unless we have recourse to the force in corporeal substance
which is the cause of the motion. I admit that there is no
need to mention these substances and qualities in order to
explain particular phenomena, but neither is there any need
to mention the intervention of God, the composition of the
continuum, the plenum, and countless other things. We
can explain mechanically, I fully admit, the particularities
of nature; but my point is that after having accepted or
assured the principles of mechanics themselves, we cannot
establish them a priori except by metaphysical arguments;
and even the difficulties de compositione continui l will never
be resolved so long as extension is regarded as constituting
the substance of bodies, and we go on embarrassing ourselves
by our own chimeras.

1 Cf. p. 76, note 3.

LEIBNIZ AND ARNAULD 81

I think, too, that to allow genuine unity or substance to
man almost alone is to be as limited in metaphysics as those
people were in physics who confined the world within a ball.
And as genuine substances are so many expressions of the
whole universe taken in a certain sense, and so many repro-
ductions of Divine works, it is in agreement with the great-
ness and beauty of these works of God, since these substances
do not hinder one another from accomplishing as much in
this universe as each of them can and as much as superior
reasons allow. . . .

I agree that there are degrees of accidental unity; that an
ordered society has more unity than a confused mob, and
that an organized body or a machine has more unity than a
society that is to say there is more point in conceiving them
as one single thing, because there is more relation between the
constituent parts. But in the end all these unities only
receive their existence from thoughts and appearances, like
colours and all other phenomena, which for all that are called
real. The tangibility of a heap of stones or of a block of
marble does not any the more prove its substantial reality
than the visibility of a rainbow proves the substantial
reality of the rainbow; and as there is nothing so solid that it
has not some degree of fluidity, perhaps this block of marble
is only a heap made of an infinity of living bodies, or is like a
lake full of fish, although these living creatures cannot
ordinarily be distinguished by the eye except in the case of
bodies that are half rotted. We may say then of these
composites and of similar things what Democritus so well
said of them, namely, csse opinione, lege, vofup. 1 Plato held
the same view about everything which is purely material.
Our mind notices or conceives a number of genuine sub-
stances which have certain modes; these modes involve rela-
tions to other substances, and so the mind takes occasion to
1 ' they depend for their existence on opinion or custom*.

82 LEIBNIZ AND ARNAULD

join them together in thought and to give an inclusive name
to all the things together. This is a convenience for reasoning ;
but we must not allow ourselves to be misled into making of
them so many substances or genuinely real entities. This only
befits those people who go no further than appearances, or else
those who make realities of all the abstractions of the mind,
and who conceive of number, time, place, motion, figure, and
sensible qualities as so many separate entities. Whereas I
hold that philosophy cannot be better established, and
reduced to some degree of precision, than by learning to
recognize the only substances or complete entities, endowed
as they are with a genuine unity in their different states
following one another, all the rest being nothing but phe-
nomena, abstractions, or relations.

No kind of arrangement will ever be found which can make
a genuine substance out of a number of entities by aggrega-
tion. For example, if the parts which fit together into one
and the same design are more competent to produce a
genuine unity than are parts which are in contact, then all
the officials of the Dutch East India Company will make a real
substance far better than a heap of stones. But what else is
a common design but a resemblance, or rather an ordered
arrangement of actions and passions, which our mind notices
in different things? If on the other hand we prefer the unity
based on contact, we are faced by other difficulties. Hard
bodies have perhaps nothing uniting their parts except the
pressure of surrounding bodies and of themselves, and in
their substance are no more united than a heap of sand,
arena sine calce. 1 Or, consider a number of rings interlaced
to make a chain: why should they compose a genuine sub-
stance thus any more than if they had openings in them
through which they could be separated? It may be that one
of the parts of the chain does not touch another and even

x 'sand without lime', i.e. without anything to bind it into
mortar.

LEIBNIZ AND ARNAULD 83

does not enclose it, and yet they are so interlaced that
unless they are taken in a certain manner they cannot be
separated, as in the figure here given. Are we to sayjn that
case that the substance of the com-
pound of these things is as it were in
suspense and depends on the future
address of whoever may wish to dis-
entangle them? These are all fictions
of the mind; and so long as we do not
distinguish what is genuinely a com-
plete entity, or substance, we shall
never have any fixed point at which we can stop; and such
fixed point is the one and only means of establishing solid
and real principles.

In conclusion, nothing should be taken as certain without
foundations; it is therefore for those who manufacture
entities and substances without a genuine unity to prove
that there is more reality than I have just said; and I am
waiting for the notion of a substance, or of an entity, which
successfully comprehends all these things; after which parts
and perhaps even dreams will be able one day to lay claim
to reality, unless very precise limits are set to this droit de
bourgeoisie 1 which is to be accorded to entities formed by
aggregation.

I have written at some length on these matters, so that
you may be able to form some opinion not only of my views,
but also of the reasons which have driven me to adopt
them. . . .

1 Leibniz seems to mean a kind of inferior citizenship. A
bourgeois was originally a member of a small township who had
certain rights akin to those of a citizen in a city.

84 LEIBNIZ AND ARNAULD

To Arnauld. 9 October 1687

. . . You reply that you have no clear idea of what I
mean by the word express. If I mean by it a thought, you
say, you do not agree that the soul has any more thought
and knowledge of the movement of the lymph in its lymphatic
ducts than of the movements of the satellites of Saturn; if
I mean something else, you do not know what I mean, and
consequently (supposing that I cannot explain myself dis-
tinctly) this term will be of no use to make clear how the
soul can give itself the sensation of pain, since for that it
would be necessary (so you say) for it to know beforehand
that I am being stung, instead of learning of the sting by
feeling the pain. In reply to your objection, I will first
explain the term which you find obscure, and then apply it
to the difficulty you raise. One thing expresses another (in
my language) when there is a constant and ordered relation
between what can be asserted of the one and what can be
asserted of the other. In this sense a projection in perspective
expresses its ground plan. 1 Expression is common to all forms,
and is a genus of which natural perception, animal sensation,
and intellectual knowledge are species. In natural percep-
tion and in sensation it is sufficient that what is divisible
and material, and is to be found dispersed in a number of
entities, should be expressed or represented in a single
indivisible entity, or in a substance possessing a genuine
unity. There can be absolutely no doubt of the possibility
of a good representation of several things in one single thing;
for our soul presents us with an example. This representa-
tion is accompanied by consciousness in a rational soul, and
it is then that it is called thought.

Now such expression is to be found on all sides, because
every substance sympathizes with every other and receives
1 son giomitYal. Cf . p. 60, note.

LEIBNIZ AND ARNAULD 85

some proportionate change, answering to the least change
which occurs in the universe; though this change is more
or less noticeable in proportion as the other bodies or their
activities have more or less relation to ours. On this point
I think M. Descartes himself would have agreed; for he
would certainly grant that because of the continuity and
divisibility of all matter the effect of the least movement is
extended over all the neighbouring bodies, and consequently
from body to body ad infinitum, though diminishing pro-
portionately. Thus our body must be affected to some
extent by the changes in all the others.

Now to all the movements of our body there correspond
certain perceptions or thoughts of our soul, more or less
confused; so the soul in turn will have some thought of all
the movements of the universe, and according to my opinion
every other soul or substance will have some perception or
expression of them. It is true that we do not perceive
distinctly all the movements of our body, as for example
the movement of the lymph; but (to make use of an example
which I have employed previously) it is like this. It must
be the case that I have some perception of the movement
of each wave on the shore if I am to be able to apperceive
that which results from the movements of all the waves
put together, namely the mighty roar which we hear by
the sea. Similarly we feel some confused result of all the
movements which take place in us, but, being accustomed
to this internal movement, we do not apperceive it distinctly
and reflectively except when there is a considerable change for
the worse, as at the beginning of an illness. And it would be
an excellent thing if physicians devoted themselves to
distinguishing more exactly these kinds of confused sensa-
tions which we have of our bodies. Now since we do not
apperceive the other bodies except by the relation which
they bear to ours, I was quite right in saying that the soul
expresses better what belongs to our body, and that we

86 LEIBNIZ AND ARNAULD

only know of the satellites of Saturn or of Jupiter in
consequence of a movement occurring within our eyes. . . .

With regard to minds, that is to say substances which
think, and are capable of knowing God and of discovering
eternal truths, I hold that God governs them by laws
different from those by which He governs the rest of sub-
stances. All forms of substances express the whole universe;
but it may be said that brute substances express the world
rather than God, while minds express God rather than the
world. Moreover God governs brute substances by the
material laws of force, or of the communication of motion,
whereas He governs minds by the spiritual laws of justice,
of which the other substances are incapable. It is for this
reason that brute substances may be called material, because
the economy which God observes in regard to them is that
of a Workman or a Mechanician; whereas in regard to
minds, God fulfils the function of Prince or Legislator, which
is infinitely more exalted. And since God is nothing in
regard to these material substances but that which He is
in regard to everything, namely the general Author of all
entities, He takes on, in regard to minds, a different char-
acter, such that He must be conceived as invested with will
and moral qualities; since He is Himself a mind, and as it
were One among us, even to the point of entering with us
into a social community of which He is the chief. It is
this society or general Commonwealth of Minds under this
sovereign Monarch which is the noblest part of the universe,
composed of so many little gods under this great God.
For created minds differ from God only as less from greater,
as finite from infinite. And we may be truly assured that
the whole universe was created only to contribute to the
adornment and to the happiness of this City of God. This
is why everything is so disposed that the laws of force, or
purely material laws, conspire in all the universe to execute

LEIBNIZ AND ARNAULD 87

the laws of justice or of love, and that nothing can hurt the
souls that are in the hand of God, and that all things must
work together for the greatest good of those who love Him.
This is why, since minds must keep their personality and
their moral qualities, to the end that the City of God may
not lose any person, it must be that in particular they should
keep some manner of reminiscence or consciousness, or the
power of knowing what they are; on this depends all their
morality, punishments, and chastenings. Consequently it
is necessary that every mind should be immune from those
revolutions of the universe which would render it entirely
unrecognizable to itself, and would make of it, morally
speaking, a different person. Whereas for brute substances
it is sufficient that each should simply remain the same
individual in the strict metaphysical sense, even though it
is subjected to all imaginable changes, since in any case it
is without consciousness or reflection. . . .

LETTER TO BAYLE *

ON THE CARTESIAN THEORY OF THE QUANTITY OF MOTION. 1687

WHEN I gave myself the valuable pleasure of reading your
Nouvelles de la Republique des Lettres, I found there my
objection to the famous Cartesian principle regarding the
Quantity of Motion, together with the Reply of a Cartesian
scholar from Paris, by name M. 1'Abbe C. 2 I now send you
my answer so that all the parts of the business may be
collected together, if you consider that suitable. It is true
that this is merely intended to clear up the matter, by
following out rather than by justifying the objection I there
raised; for M. 1'Abbe has in fact offered no opposition to it,
but grants me more than I want. However, I am very
much afraid that the other Cartesians may repudiate what
he says.

According to him, the Cartesian rule is limited in applica-
tion, and is indeed a very small matter; he maintains that it is
only a particular Principle regarding the five Common Machines
and concerned with isochronic -powers, or movements recorded
in equal times. I had shown that in a certain case (which
was sufficiently ordinary), and in an infinite number of other
similar ones, two bodies have the same force although they
have not the same quantity of motion. He grants this, and
I ask no more. But he adds that this is not surprising,
because in the case referred to the two bodies acquired their
forces in unequal times: as if the principle ought to be limited
to forces acquired in equal times. This is to grant me my
case, and indeed I do not ask so much. But as against the

1 Pierre Bayle (1647-1706), author of the famous Historical
and Critical Dictionary. Cf. pp. 118-40.

a probably Jean de Catellan, Bishop of Vallence.
88

THE QUANTITY OF MOTION 89

Cartesians I should be wrong to try to take advantage of the
fact that they are so feebly defended. For I do not believe
that M. PAbbe C. would ever find one of them, at least among
those who pass for geometricians, to approve of his restriction
of the principle. You, sir, will be able to decide, and I have
no doubt but that some clever Cartesians among your friends
will admit it, if you think fit to consult them; which I should
make bold to ask you to do, if I knew what your convenience
allowed. The Cartesians claim in general that there is
always maintained the same sum total of force, which they
always estimate by the quantity of motion. And according
to them, if some bodies transfer their force, or a part of their
force, to others, there will be in all these bodies together the
same quantity of motion as before, or the sum total of the
products of the masses multiplied by their velocities will be
the same. For example, if there is a body weighing 4 pounds,
with a velocity of i degree, and we suppose that its whole
force must now be transferred to a body weighing i pound,
is it not true that the Cartesians assert that in this case
the body must receive a velocity of 4 degrees for the same
quantity of motion to be preserved? For mass 4 multiplied
by velocity i produces the same result as mass i multiplied
by velocity 4. According to my view, on the other hand,
the body in question must only receive a velocity of 2 degrees
(as I will prove below); so the difference between us is mani-
fest enough. And in estimating in this way the force which
the bodies have acquired, neither these gentlemen nor any
others that I know of (with the exception of M. 1'Abbe C.)
have worried themselves about whether they were gained
in a long or short, an equal or an unequal time. Time,
indeed, has nothing to do with this calculation. When we
see a body of a given magnitude travelling at a given velocity,
can we not estimate its force without knowing in what length
of time and with what detours and delays it may have acquired
that velocity? It seems to me that in this case we can judge

90 THE QUANTITY OF MOTION

of the present state without knowing the past. When there
are two bodies, perfectly equal and similar, whose velocities
are the same but acquired in the one case by a sudden shock,
and in the other by a descent of observable duration, are we
for that reason to say that their forces are different? This
would be like saying that that man is richer whose money
has taken longer to acquire. But, what is more, it is not
even necessary that the two bodies in my suggested instance
should fall from their different heights in unequal times, as
is supposed by M. PAbbe C.; he did not see that the time
taken over the descent may be changed at will, according as
the line of descent is changed by being given a greater or less
inclination, and that there are an infinite number of ways in
which these two bodies may be made to descend from their
different heights in equal times. For if we disregard the
resistance of the air and similar hindrances we know that a
body falling from the same height acquires the same velocity
whether the descent be perpendicular and sudden, or sloping
and not so fast. Consequently the distinction of times does
not affect my objection. These things are so evident that I
might perhaps return to M. PAbb6 C. the compliment of
some of his expressions, but I think it is more fitting not to
descend to these amusements. The fact is, I think, that my
objection is so simple that its very simplicity operated to
deceive him, since he could not believe that a comment which
was so easy could have escaped the notice of so many able
people. This is why, noticing the difference in the times, he
leapt upon that, without giving himself leisure to reflect that
it is only incidental. I have a sufficiently good opinion of
his mind and of his sincerity to hope that he will now agree
about this himself, and I think that what follows will help
even more to make him see the truth of the matter. In
order, too, to anticipate the doubts of those who may think
it is a satisfactory answer to my objection to say that the
insensible matter which presses heavy bodies downwards

THE QUANTITY OF MOTION 91

and causes their acceleration, has lost exactly the quantity
of motion which it imparts to the bodies; I answer that I
agree about this pressure which is the cause of weight, and
that I hold that this Ether loses as much force (though not as
much motion) as it imparts to the heavy bodies; but that all
this does nothing to resolve my objection, even if I granted
(contrary to the truth) that the Ether lost as much motion
as it imparted. For my objection is expressly so stated that
it does not matter how the force was acquired ; I left that
out of account so as not to enter into any disputes on any
hypothesis in that regard. I take the acquired force and
the acquired velocity as they are, without bothering about
whether they were imparted suddenly by a shock from another
body or little by little by a continual acceleration from gravity
or from a spring. It is sufficient for me that the body now
has this given force or rather this given velocity. And under
those circumstances I show that its force must not be esti-
mated by the velocity or quantity of motion; and that the
body can give its force to another body without giving it
its quantity of motion, and that therefore when this trans-
ference occurs, it may, and indeed it must, happen that the
quantity of motion is diminished or increased in the bodies,
while the same force remains.

I shall now prove what I put forward above, namely, that
if we suppose the whole force of one body, which weighs 4
pounds and whose velocity (when it travels in a horizontal
plane, in whatever manner it acquires its velocity) is i degree,
is transferred to another body weighing i pound, then the latter
body will receive a velocity, not of 4 degrees in accordance with
the Cartesian principle, but of 2 degrees only] because in this
way the bodies or weights would be in reciprocal ratio to
the heights to which they could ascend by virtue of the
velocities they possess. Now these heights are as the
squares of their velocities. And if the body weighing 4
pounds with its velocity in a horizontal plane of i degree,

92 THE QUANTITY OF MOTION

on meeting and becoming attached to the end of a pendulum
or perpendicular line, climbs to a height of i foot, the body
weighing i pound will have a velocity of 2 degrees, in order
to be able, when similarly attached, to ascend to a height
of 4 feet. For it requires the same force to raise 4 pounds
i foot, as to raise i pound 4 feet. But if this body weighing
i pound was bound to receive 4 degrees of velocity, as
Descartes believed, it would be able to climb to a height
of 16 feet. And consequently the same force which raised
4 pounds i foot, would be able, if transferred to i pound,
to raise it 16 feet. But this is impossible; for the effect is
four times as great, which means that three times the force
which was originally present has been acquired and derived
from nothing. This is why I hold that in place of the
Cartesian principle it is possible to set up another Law of
Nature which I consider most universal and most inviolable,
namely that there is always a perfect equation between the full
cause and the entire effect. This principle does not assert
merely that effects are proportional to causes, but more
than this, that each complete effect is equivalent to its
cause. And although this axiom is altogether metaphysical,
it is none the less one of the most useful in physics, and
provides a means of reducing forces to a geometrical calculus.
But in order to show more clearly how it must be made
use of, and why Descartes and others departed from it,
let us consider his third rule of motion, as an example.
Let us suppose that two bodies B and C, each weighing
i pound, meet one another, B with a velocity of 100 degrees,
and C with a velocity of i degree. Their total quantity of
motion will be 101. But if C with its velocity can climb i
inch, B with its velocity will be able to climb 10,000 inches.
Thus the force of both together is capable of raising i pound
io,ooi inches. Now according to the third Cartesian rule,
after the shock they will travel together in company at a
velocity of 50$, so that when multiplied by 2 (the number

THE QUANTITY OF MOTION 93

of pounds travelling together after the shock) there results
the same quantity of motion, 101. But in that case these
2 pounds will only be capable of ascending together to a
height of 2,55<>i inches (i.e. the square of 50$), which is the
same as if they had the force to raise i pound 5,iooJ inches,
whereas before the shock there was force enough to raise
i pound 10,001 inches. Thus nearly half the force will
have been lost by virtue of this rule for no reason whatever,
and without being used for anything. This is just as im-
possible as what we showed above in another case, where
by virtue of the same Cartesian general principle three times
the force could be acquired for no reason.

The famous author of the Recherche de la Verite 1 has
indeed seen some errors of M. Descartes in these matters;
but as he presupposed the maxim which I reject, he held
that of the seven Cartesian rules numbers i, 2, 3, and 5 were
true, whereas the only one which can be maintained is the
first, which is self-evident. The same author of the Recherche,
arguing on the supposition of bodies that are hard and
without elasticity, maintains that they cannot spring back
nor become separated after the shock, except when they
meet one another with velocities in reciprocal relation to
their magnitudes, and that in all other cases they will travel
in company after the shock, preserving the original quantity
of motion. But in this I find a serious difficulty. If body
B, of magnitude 2 and velocity i, and body C, of magnitude
i and velocity 2, move directly against one another, he grants
that they will spring back at their own velocities. But if
we suppose the velocity or the magnitude of one of the
bodies, say B, to be increased by ever so little, he maintains
that both will travel together in the direction in which
B previously travelled alone, and this at a velocity of
approximately , supposing that the change in B is so slight
that in calculating the quantity of motion it is possible to
1 Malebranche.

94 THE QUANTITY OF MOTION

retain the original numbers without any error worth men-
tioning. But is it credible that simply because of the
smallest conceivable change assumed in regard to the body
B, there should arise so great a difference in the result that
all springing back should cease, and that B, which had in
the previous instance to turn back at a velocity of i, should
now not only not have to travel backwards, but should even
travel forwards at a velocity of approximately ^ which is
all the more strange in that before the shock it only travelled
forward at a velocity of i ? Thus the other body, instead
of making this one recoil, or advance less, as a result of the
shock of impact, makes it advance more, and as it were
attracts it to itself which is beyond all probability. As
it is the author of the Recherche de la Verite to whom we
are indebted for the correction of a number of Cartesian
prejudices of some importance, elsewhere as well as on this
matter, it seemed to me fitting that I should explain here
what else remained to be said. As I am assured that he
is as honourable as he is penetrating, I have no fear that
he may take it ill of me, but rather await his approbation.

However, I think that M. Descartes, who in laying down
his rules forgot to notice the cases where two unequal bodies
move against one another with unequal velocities, would
have been obliged in the case just mentioned to say the
same as the author of the Recherche, so far as I can judge
from his third rule, about which they are both agreed.
But there will still occur the inequality of the effect and
the cause, as it would be easy to show by calculation on the
example of the third rule. This inequality is also to be
found in what the author of the Recherche says in correction
of M. Descartes's fourth, sixth, or seventh rules. In regard
to the sixth rule, for example: let B be of weight i pound
and velocity 4, and C of weight i pound and at rest. He
maintains that they travel in company after the shock at
a velocity of 2. Thus whereas previously there was a force

THE QUANTITY OF MOTION 95

capable of raising i pound 16 feet, there is now only a force
capable of raising 2 pounds 4 feet, and half the force has been
lost. According to M. Descartes, in this case B and C will
travel in the same direction, and B's velocity will be 3,
C's will be i; thus in all there will be a force capable of
raising i pound 10 feet, and more than a third of the force
will have been lost.

What may have misled these worthy authors, and has
caused most confusion in this matter, is that bodies whose
velocities are reciprocally related to their extensions are
observed to stop one another, both in a balance and outside.
This is why their forces were believed to be equal, all the more
because no account was taken in bodies of anything except
velocity and extension. It is in this connection that it would
have been of value to make use of the distinction between force
and direction, or rather between the absolute force necessary
to cause the existence of some effect (for example, to raise a
certain weight to a certain height, or to compress a certain
spring to a certain degree) and the force required to travel
forward in a certain direction, or to maintain the direction.
For although a body of magnitude 2 with velocity i and a
body of magnitude i with velocity 2 stop one another or
prevent one another from going forward, nevertheless if the
first can raise a pound 2 feet, the second will be able to raise
a pound 4 feet. This is paradoxical, but it cannot be doubted
after what has just been said. It might be possible, however,
to find some new interpretation of the principle of the
quantity of motion, so that after such correction it might
remain a universal principle; but it is not easy to see what it
would be.

I will add a remark of some consequence for metaphysics. I
have shown that force must not be estimated by compounding
the velocity and the magnitude, but by its future effect. Yet
it seems that force or power is something real at the present
moment, and the future effect is nott Whence it follows that
I95

g6 THE QUANTITY OF MOTION

it is necessary to admit in bodies something other than magnitude
and velocity) unless we are willing to deny to bodies all power
of action. I hold, moreover, that we have not a sufficiently
perfect conception even of matter and extension. The
author of the Recherche de la Verite has recognized the
existence of such obscurity in regard to the soul and to
thought, thereby differing from the Cartesians, but as
regards matter and extension he appears to agree with
them. . . .

EXPOSITION AND DEFENCE OF THE NEW SYSTEM

NEW SYSTEM OF THE NATURE AND COMMUNICATION OF SUB-
STANCES, AS WELL AS OF THE UNION EXISTING BETWEEN THE
SOUL AND THE BODY. 1695

IT is now some years since I conceived this system, and
entered into communication about it with several learned
men, and in particular with one of the greatest theologians
and philosophers of our time, 1 who had heard of some of my
opinions from a personage of the highest rank, and found
them highly paradoxical. But when he had received my
explanations, he retracted in the most generous and edifying
way imaginable, expressed his approval of a part of my
propositions, and withdrew his censure of the others with
which he still did not agree. Since that time I have con-
tinued my meditations as opportunity offered, so as to give
to the public well-considered opinions only: and I have tried
also to satisfy the objections raised against my Essays on
Dynamics, which have some connection with this. Some dis-
tinguished people, moreover, have desired to see my opinions
more clearly expressed, and so I venture to offer these medi-
tations, although they are in no way popular, nor such as to
be to the taste of all kinds of minds. My chief aim is to give
myself the benefit of the judgment of those who are en-
lightened in these matters, since it would be too difficult to
seek out and call to my aid individually those who would
be prepared to give me instruction which I shall always be
very happy to receive, provided the love of truth appears
therein, and not merely a passion for preconceived opinions.
1 Arnauld. Cf. pp. 52-87.
97

98 THE NEW SYSTEM

Although I am one of those who have done much work on
mathematics, I have constantly meditated on philosophy
from my youth up, for it has always seemed to me that in
philosophy there was a way of establishing something solid
by means of clear proofs. I had travelled far into the world
of the Scholastics when mathematics and modern writers
lured me out again, while still a young man. I was charmed
with their beautiful way of explaining nature mechanically,
and scorned, with justice, the method of those who only make
use of forms or faculties, from which we learn nothing. But
later, when I tried to get to the bottom of the actual principles
of mechanics in order to give an explanation of the laws of
nature which are known through experience, I became aware
that the consideration of an extended mass is not of itself
enough, and that use must also be made of the notion of
force, which is fully intelligible, although it falls within the
sphere of metaphysics. It seemed to me also that the opinion
of those who transform or degrade the lower animals into
mere machines, though it seems possible, is improbable, and
even against the order of things.

At first, when I had freed myself from the yoke of Aristotle,
I had believed in the void and atoms, for it is this which
best satisfies the imagination. But returning to this view
after much meditation, I perceived that it is impossible to
find the principles of a true unity in matter alone, or in what
is merely passive, since everything in it is but a collection or
accumulation of parts ad infinitum. Now a multiplicity can
be real only if it is made up of true unities which come from
elsewhere and are altogether different from mathematical
points, which are nothing but extremities of the extended
and modifications out of which it is certain that nothing
continuous could be compounded. Therefore, to find these
real unities, I was constrained to have recourse to what
might be called a real and animated point or to an atom of
substance which must embrace some element of form or of

THE NEW SYSTEM 99

activity in order to make a complete being. It was thus
necessary to recall and in a manner to rehabilitate substantial
forms, which are so much decried to-day, but in a way which
makes them intelligible and separates the use which must be
made of them from their previous abuse. I found then that
their nature consists of force and that from this there follows
something analogous to feeling and to appetite; and that
therefore it was necessary to form a conception of them
resembling our ordinary notion of souls. But just as the
soul must not be used to explain the detail of the economy of
the animal's body, so I judged in the same way that these
forms ought not to be used to explain the particular problems
of nature, although they are necessary to establish true
general principles. Aristotle calls them first entelechies ; I
call them, more intelligibly perhaps, primary forces, which
contain not only the act, or the fulfilment of possibility, but
also an original activity.

I saw that these forms and these souls must be indivisible
like our mind ; and indeed I recollected that this had been the
opinion held by St. Thomas concerning the souls of the lower
animals. But this truth revived the great difficulties about
the origin and duration of souls and forms. For since every
simple substance which possesses a true unity can have its
beginning and end by miracle alone, it follows that they
could not begin except by creation, nor come to an end except
by annihilation. Thus (with the exception of such souls as
God still wills to create expressly) I was obliged to recognize
that the constitutive forms of substance must have been
created with the world and that they go on subsisting always.
Moreover, some of the Scholastics, such as Albert the Great
and John Bacho, had a notion of some part of the truth about
their origin. Nor ought our view to appear extraordinary,
since we are only attributing to forms duration, which was
granted to their atoms by the followers of Gassendi.

Nevertheless I deemed that we ought not to mix without

ioo THE NEW SYSTEM

distinction or to confuse with other forms or souls, minds or
rational souls, which are of a superior order and have incom-
parably more perfection than those forms embedded in matter
which, on my view, are to be found everywhere, since in
comparison with these others, minds or rational souls are
little gods, made in the image of God, and having in them
some glimmering of Divine light. This is why God governs
minds as a prince governs his subjects, or as a father cares
for his children; whereas He disposes of other substances as
an engineer handles his machines. Thus minds have special
laws which set them above the revolutions of matter, by the
very order God has introduced into them; and it may truly
be said that all the rest is made for them alone, the very
revolutions being arranged for the felicity of the virtuous
and the punishment of the wicked.

But to return to ordinary forms or brute souls, the fact
that duration must now be attributed to them instead of
to atoms as previously, might give rise to the doubt whether
they do not pass from one body to another; this would be
metempsychosis, more or less as some philosophers have
thought occurred in the transmission of movement and of
character. But this fancy is very far removed from the
nature of things. There is no such passing. It is here that
the transformations of MM. Swammerdam, Malpighi, and
Leeuwenhoek, who are among the best observers of our day,
have come to my assistance and have made me admit more
readily that the animal and every other organized substance
does not begin when we think, but that its apparent genera-
tion is only a development, a kind of increase. I have
noticed, too, that the author of the Recherche de la Verite?
M. Regis, M. Hartsoeker, and other clever men have not
been very far removed from this opinion.

But there still remained the more important question of
what becomes of these souls or forms at the death of the
1 Malebranche.

THE NEW SYSTEM 101

animal, or at the destruction of the individual unit of
organized substance. This question is the more awkward,
inasmuch as it seems unreasonable that souls should remain
useless in a chaos of confused matter. This ultimately
made me decide that there was only one sensible thing to
believe; that is to maintain the conservation not only of the
soul but also of the animal itself and of its organic machine ;
even though the destruction of its grosser parts has reduced
it to such smallness that it evades our senses, just as it did
before birth. Moreover, nobody can mark precisely the true
time of death, which may for a long time pass for a mere
suspension of observable actions, and fundamentally is never
anything else but that in the case of simple animals; witness
the resuscitations of flies which have been drowned and then
buried under powdered chalk, and several similar instances,
which make us realize that there might be other resuscita-
tions, and in cases which were much further gone, if men
were in a position to readjust the machine. And it looks
as though it were something of this nature which was
discussed by the great Democritus, thoroughgoing atomist
though he was, although it was made fun of by Pliny. It
is therefore natural that since the animal has always been
living and organized (as some people of fine penetration are
beginning to recognize), it should also always continue to
be so. And since there is thus no first birth or entirely
new generation of the animal, it follows that it will suffer
no final extinction or complete death, in the strict meta-
physical sense; and that consequently instead of a transmigra-
tion of souls, there occurs only a transformation of one and
the same animal, according as its organs are differently
folded, and more or less developed.

But rational souls obey much more exalted laws, and are
immune from anything which could make them lose the
status of citizens of the society of minds, since God has so
well provided that no changes of matter could make them

102 THE NEW SYSTEM

lose the moral qualities of their personality. And it may be
said with truth that everything tends to the perfection not
only of the universe in general, but also of these created
beings in particular, who are destined for so high a degree
of happiness that the universe becomes concerned in it by
virtue of the divine goodness which is communicated to
each created being, in so far as sovereign wisdom can permit.

As regards the ordinary body of animals and other cor-
poreal substances, which have hitherto been held to suffer
complete extinction, and whose changes depend rather on
mechanical rules than on moral laws, I was pleased to note
that the ancient author of the book Of Regimen, which is
attributed to Hippocrates, had some notion of the truth
when he expressly says that animals neither are born nor
die, and that the things which are thought to come into
being and to perish merely appear and disappear. This
was also the opinion of Parmenides and of Melissus in the
pages of Aristotle. For these ancient thinkers are sounder
than is supposed.

I am as willing as any man to give the moderns their due;
but I think they have carried reform too far, among other
things in confusing the natural with the artificial, through
not having had sufficiently exalted ideas of the majesty of
Nature. They conceive that the difference between her
machines and ours is but the difference between the great
and the small. This recently led a very clever man 1 to
remark that when looking at Nature from near at hand she
appears less admirable than we thought, being no more than
a workman's shop. I believe that this does not give a
sufficiently just idea, or one sufficiently worthy of her, and
there is no system except mine which properly exhibits
the immense distance which really lies between the least
productions and mechanisms of Divine wisdom and the
greatest achievements of the skill of a limited mind. This
1 Fontenelle.

THE NEW SYSTEM 103

difference is one not merely of degree, but of kind also. It
must be recognized that Nature's machines possess a truly
infinite number of organs, and are so well protected and
armed against all accidents, that it is not possible to destroy
them. A natural machine still remains a machine in its
least parts, and, what is more, it always remains the very
same machine that it was, being merely transformed by the
different foldings it receives, and being sometimes stretched,
sometimes contracted and as it were concentrated, when
we think that it is destroyed.

Furthermore, by means of the soul or form, there is a true
unity which corresponds to what is called the I in us; a thing
which could not occur in artificial machines, nor in the simple
mass of matter, however organized it may be. This can
only be regarded as like an army or a flock, or like a pond full
of fish, or a watch made up of springs and wheels. Yet if
there were no true substantial unities, there would be nothing
real or substantial in the collection. It was this that com-
pelled M. Cordemoy to abandon Descartes, and to adopt
Democritus's theory of atoms, in order to find a true unity.
But atoms of matter are contrary to reason, besides the fact
that they also are composed of parts, since the invincible
attachment of one part to another (granted that this could
be reasonably conceived or supposed) would not destroy their
diversity. It is only atoms of substance, that is to say unities
which are real and absolutely without parts, which can be
the sources of actions, and the absolute first principles of
the composition of things, and as it were the ultimate elements
into which substantial things can be analysed. They might
be called metaphysical points, there is about them something
vital and a kind of perception, and mathematical points are
their points of view for expressing the universe. But when
corporeal substances are contracted all their organs consti-
tute to us but a physical point. Thus physical points are
indivisible in appearance only: mathematical points are

104 THE NEW SYSTEM

exact, but they are nothing but modalities. It is only
metaphysical points, or points of substance (constituted by
forms or souls), which are both exact and real; and without
them there would be nothing real, since without true unities
there would be no plurality.

Once I had established these things, I thought I had
reached port; but when I set myself to reflect on the union
of the soul with the body, I seemed to be cast back again into
the open sea. For I could find no way of explaining how
the body causes something to happen in the soul, or vice
versa, nor how one created substance can communicate with
another. M. Descartes left the field at this stage, as far as
we can gather from his writings; but his disciples, realizing
that the common opinion is inconceivable, maintained that
we are aware of the qualities of bodies because God produces
thoughts in the soul on the occasion of the movements of
matter; and when our soul wishes to move the body in its
turn, they deemed that it is God that moves it for the soul.
And as the communication of motion seemed to them like-
wise inconceivable, they maintained that God gives motion
to a body on the occasion of the motion of another body. This
is what they call the System of occasional causes, which has
become very fashionable owing to the fine reflections of the
author of the Recherche de la Vented

It must be admitted that they have gone a great way in
regard to this problem by showing what cannot possibly
take place; but their explanation of what does in fact occur
does not remove the difficulty. It is quite true that in the
strict metaphysical sense there is no real influence exerted by
one created substance on another, and that all things, with
all their realities, are continually produced by the power of
God: but to solve these problems it is not enough to make
use of the general cause, and to drag in what is called the
dens ex machina. For when this is done without giving any
1 Malebranche.

THE NEW SYSTEM 105

further explanation in terms of the order of secondary causes,
this is properly speaking to fall back on miracle. In
philosophy, we must attempt to give an account showing in
what way things are brought about by the Divine wisdom,
in conformity with the notion of the subject in question.

Being thus constrained to grant that it is impossible for
the soul or for any other true substance to receive anything
from without, except by Divine omnipotence, I was in-
sensibly led to adopt a view which surprises me, but which
seems inevitable, and which does in fact possess very great
advantages and considerable beauties. This view is that
we must say that God first created the soul, and every other
real unity, in such a way that everything in it must spring
from within itself, by a perfect spontaneity with regard to
itself, and yet in a perfect conformity with things outside.
And thus, since our internal sensations (those, that is to say,
which are in the soul itself and not in the brain or in the
subtle parts of the body) are but phenomena dependent upon
external entities, or rather are really appearances, and, as it
were, well ordered dreams, these internal perceptions within
the soul itself must arise in it from its own original constitu-
tion, that is to say through the natural representative ability
(capable of expressing entities outside itself in relation to
its organs) with which it has been endowed since its creation,
and which constitutes its individual character. It follows
from this that, since each of these substances exactly repre-
sents the whole universe in its own way and from a certain
point of view, and since the perceptions or expressions of
external things reach the soul at a determined point by
virtue of its own laws and, as it were, in a world apart, as if
nothing else existed but only God and itself (if I may make
use of a way of speaking employed by a certain writer with
a most exalted mind and famous for his holiness), there will
be a perfect agreement between all these substances, pro-
ducing the same effect as would occur if these communicated

106 THE NEW SYSTEM

with one another by means of a transmission of species or
qualities, as the common run of philosophers maintain.
Furthermore, the organized mass, within which is the point
of view of the soul, is itself more nearly expressed by it, and
finds itself in its turn ready to act of itself according to
the laws of the corporeal machine whenever the soul desires,
without either disturbing the laws of the other, the animal
spirits and the blood having precisely at the given moment
the motions necessary to make them respond to the passions
and perceptions of the soul; and it is this mutual relation,
regulated in advance in every substance in the universe, which
produces what we call their communication) and which alone
constitutes the union of the soul and the body. And this makes
it possible to understand how the soul has its seat in the body
by an immediate presence, which could not be closer than
it is, since it is present in the way in which the unity is present
in that resultant of unities which is a plurality.

This hypothesis is very possible. For why should not God
be able in the first instance to give to substance a nature or
internal force capable of producing for it in order (as if it
were an automaton^ spiritual and formal, but free in the case
of a substance which has a share of reason) everything that
is going to happen to it, that is to say all the appearances and
expressions it is going to have, and that without the assistance
of any created thing? This is rendered all the more probable
by the fact that the nature of substance necessarily requires
and essentially involves a progress or change, without which
it would have no force to act. And since it is the very nature
of the soul to be representative of the universe in a very
exact way (although with varying distinctness), the sequence
of representations which the soul produces for itself will
naturally correspond to the sequence of changes in the uni-
verse itself: while on the other hand the body has also been
adjusted to the soul, in regard to the experiences in which the
latter is conceived as acting outside itself. This is all the

THE NEW SYSTEM 107

more reasonable in that bodies are only made for those minds
which are capable of entering into society with God, and of
celebrating His glory. Thus once we recognize the possibility of
this hypothesis of agreements, we recognize also that it is the most
reasonable one, and that it gives a wonderful idea of the har-
mony of the universe and of the perfection of the works of God.

There is in it this great advantage also, that instead of
saying that we are free only in appearance and in a manner
adequate for practice, as several ingenious men have held, we
must rather say that we are determined in appearance only;
and that in strict metaphysical language we are perfectly
independent as regards the influence of all other created
things. This again shows up in a marvellously clear light
the immortality of our soul, and the ever uniform conserva-
tion of our individual self, which is perfectly well regulated
of its own nature, and is beyond the reach of all accidents
from outside, whatever the appearances to the contrary.
No system has ever so clearly exhibited our exalted position.
Since each mind is as it were a world apart, sufficient unto
itself, independent of all other created things, including the
infinite, expressing the universe, it is as lasting, as subsistent,
and as absolute as the very universe of created things itself.
We must therefore conclude that it must always play its
part in the way most suited to contribute to the perfection
of that society of all minds which constitutes their moral
union in the City of God. Here, too, is a new and wonder-
fully clear proof of the existence of God. For this perfect
agreement of all these substances, which have no point of
communication with one another, could only come from the
one common cause.

Besides the fact that this hypothesis is recommended by
all these advantages, it may be added that it is something
more than a hypothesis, since it seems hardly possible to
explain things in any other intelligible way, and since
several serious difficulties which have hitherto exercised

io8 THE NEW SYSTEM

men's minds seem to disappear of themselves when once it
is properly understood. Ordinary ways of speaking can
still be easily retained. For it may fairly be said that when
the particular disposition of a given substance is the explana-
tion of a change taking place in an intelligible manner, so
that we can infer that it is to this substance that the others
have been adjusted in this regard from the beginning, in
accordance with the order of the decrees of God, then that
substance ought to be conceived as in that respect acting
upon the others. Further, the action of one substance on
another is not a giving forth, or transplanting of an entity,
as is commonly supposed; and it can reasonably be under-
stood only in the way I have just described. It is true that
we can easily conceive of matter both as giving out and as
taking in parts; and it is in this way that we rightly explain
in terms of mechanics all the phenomena of physics; but as
the material mass is not a substance, it can be seen that
action in regard to substance itself can only be such as
I have just described.

These considerations, metaphysical though they may
appear, are yet wonderfully useful in physics, for establishing
the laws of motion, as my Dynamics will be able to establish.
For the truth is that in the shock of impact each body
suffers only from its own reaction, caused by the motion
which is already in it. And as for absolute motion, nothing
can determine it mathematically, since everything termi-
nates in relations. This means that there is always a perfect
equivalence of hypotheses, as in astronomy; so that whatever
number of bodies we take, we may at our own discretion
assign rest, or any given degree of velocity, to any particular
one of them we wish, without its being possible for us to be
refuted by the phenomena of motion, whether in a straight
line, circular, or composite. It is, however, reasonable to
attribute to bodies true motions, in accordance with the
supposition which explains phenomena in the most intelligible

THE NEW SYSTEM 109

way; and this way of speaking is in conformity with the
notion of activity which we have just established.

EXPLANATION OF THE NEW SYSTEM OF THE COMMUNICATION
OF SUBSTANCES, IN REPLY TO WHAT is SAID ABOUT IT
IN THE 'JOURNAL* OF 12 SEPTEMBER 1695 *

... I recollect, sir, that I thought I was complying with
your desire in imparting to you my philosophical hypothesis
some years ago, though at the same time I pointed out that I
had not yet decided to acknowledge it. In return I asked your
opinion of it; but I do not remember receiving any objec-
tions from you, otherwise with my usual docility I should
certainly not have given you occasion to raise the same ones
a second time. Yet they are still not too late, although they
reach me after publication, for I am not one of those for
whom the being committed to a view takes the place of
sound reasoning, as you will find when you are able to say
you have adduced some precise and pressing reason against
my opinions which, it appears, is not your aim. You wish
rather to speak as an able Academic, and thereby to provide
an opportunity of going more deeply into the matter.

1. It was my aim here to expound, not the principles of
extension, but the principles of that which is in fact extended,
or of bodily mass. These principles, according to me, are the
real units, that is to say the substances that possess a true
unity.

2. The unity of a clock, to which you refer, is on my
view quite other than the unity of an animal; the latter
may be a substance possessing a true unity, like that in us
which is called the 7; whereas a clock is nothing but an
assemblage.

1 A letter from Foucher to Leibniz was published in this copy
of the Journal, giving a number of objections to the New System.
For an earlier letter of Leibniz to Foucher, see pp. 45-51.

no THE NEW SYSTEM

3. It is not in the disposition of the organs that I find the
principle of consciousness in animals; I agree that this
disposition concerns nothing but the bodily mass.

4. I mention these things to prevent misunderstandings
and to show that what you say about them is not contrary
to what I have propounded. It seems that you do not make
me out to be wrong when I demand true unities, and when
that makes me rehabilitate substantial forms. But when
you appear to say that the souls of brutes must have some
share of reason if they are allowed to have sensation, that is
a conclusion the proof of which I do not see.

5. You recognize with commendable sincerity that my
hypothesis of harmony or concomitance is a possible one.
But none the less you are still somewhat averse to it, no
doubt because you believed that it was purely arbitrary,
and did not realize that it follows from my view of unities,
and that my whole contention stands or falls together.

6. You therefore ask me, sir, what can be the purpose of
all this artifice which I attribute to the Author of nature
as if it were possible for too much artifice to be attributed
to Him, and as if this exact correspondence of unities with
one another through their own laws, which each received at
the beginning, were not a thing admirably beautiful in itself
and worthy of its Author. You further ask what advantage
I find in this theory.

7. I might refer to what I have already said about this.
Still, I answer in the first place that when a thing cannot
not be so, it is not necessary to ask what can be the purpose
of it before admitting it. What is the purpose of the
incommensurability of the side with the diagonal?

8. In the second place I answer that this correspondence
serves the purpose of explaining the communication of
substances and the union of the soul with the body by means
of the laws of nature established in advance, without having
recourse either to a transmission of species, which is incon-

THE NEW SYSTEM in

ceivable, or to a fresh intervention of God, which does not
appear admissible. For we must realize that as there are
natural laws in matter, so there are also natural laws in
souls or forms, and these laws mean what I have just stated.

9. I am further asked how it happens that God is not
content to produce all the thoughts and modifications of the
soul, without these useless bodies which the soul (it is said)
can neither move nor know. The answer is easy. It is that
it was God's will that there should be a greater rather than
a lesser number of substances, and He found it good that
these modifications should correspond to something outside.

10. There is no useless substance; they all have their
contribution to make to God's design.

n. Also I do not admit that the soul does not know bodies,
though this knowledge arises without their influencing one
another.

12. I should have no objection even to saying that the
soul moves the body; in the same way as a Copernican rightly
speaks of the rising of the sun, a Platonist of the reality of
matter, a Cartesian of the reality of sensible qualities,
provided these statements are sanely understood, so I believe
that it is very true to say that substances act upon one
another, provided it is understood that the one is the cause
of changes in the other in consequence of the laws of harmony.

13. The objection touching the lethargy of bodies (namely
that the bodies might be inactive even when the soul believed
them to be in motion) cannot stand because of this same
unfailing correspondence, established by Divine wisdom.

14. I have no knowledge of these vain } useless, and inactive
masses, to which reference is made. There is activity every-
where; indeed, I maintain this more than the received
philosophy, because I hold that there is no body without
motion, nor substance without force.

15. I do not understand the precise nature of the objection
contained in the words: In truth, sir, can we not see that these

K9*5

H2 THE NEW SYSTEM

views are formed with a set purpose, and that these systems,
coming after the event, have only been manufactured to vindicate
certain principles? All hypotheses are formed with a set
purpose, and all systems come after the event to vindicate
phenomena or appearances. But I do not see which are
the principles in favour of which I am supposed to be pre-
judiced, and which I want to vindicate.

1 6. If this means that I am led to my hypothesis by a
priori reasons also, or by fixed principles, as is in fact the
case, this is rather a commendation of the hypothesis than
an objection to it. It commonly suffices for a hypothesis
to be proved a posteriori, because it satisfies the phenomena;
but when we have other reasons as well, and those a priori,
it is so much the better.

17. But perhaps what is meant is that when I had invented
a new view for myself, I was very glad to make use of it,
more to assume airs on account of its novelty than because
I recognized it to be useful. I do not know, sir, whether
you have so poor an opinion of me as to attribute such
thoughts to me. For you know that I love truth; and that
if I had such a feeling for novelties, I should be in a greater
hurry to produce them, especially those whose solidity is
recognized. But in order that those who know me less
well should not endow your words with a meaning which
we should not like, suffice it to say that in my view it is
impossible to explain transeunt activity in conformity with
the laws of nature in any other way, and that I believed that
the value of my hypothesis would be recognized in view of
the difficulty which the ablest philosophers of our time have
found in the communication of minds and bodies, and even of
bodily substances one with another. I do not know whether
you yourself have encountered any of these difficulties.

1 8. It is true that there are, on my view, forces in all
substances; but these forces are, strictly speaking, only in
the substance itself; and what follows from them in the

THE NEW SYSTEM 113

other substances is only by virtue of a pre-established har-
mony, if I may use the word, and not by any real influence,
or by the transmission of some species or quality. As I have
explained the nature of activity and passivity, the nature
of force and of resistance can readily be inferred.

19. You say, sir, that you know that there are still many
more questions to be put before we can decide those which we
have been discussing. But perhaps you will find that I have
already put them: I am not sure that your Academics have
put into practice the valuable parts of their method more
rigorously and effectively than I myself have done. I
strongly approve of the attempt to prove truths from first
principles; this is more useful than is commonly supposed,
and I have often put this precept into practice. Thus I
welcome what you say on this subject, and I hope your
example will lead our philosophers to think about it as
they should.

20. I will add a further reflection which seems to me to
be of considerable assistance towards the better understand-
ing of the reality and value of my system. You know that
M. Descartes believed that the same quantity of motion is
conserved in bodies. It has been demonstrated that he was
mistaken in this; but I have shown that it is always true
that the same motive force instead of, as he thought, the
same quantity of motion is conserved. Even so, the
changes which take place in the body as a consequence of
the modifications of the soul caused him embarrassment,
because they seemed to violate this law. He thought there-
fore that he had found a way out of the difficulty, which is
certainly ingenious, by saying that we must distinguish
between motion and direction of motion; and that the soul
cannot increase or diminish the motive force, but that it
changes the direction or determination of the course of the
animal spirits, and it is in this way that voluntary motions
take place. It is true that he made no attempt to explain

H4 THE NEW SYSTEM

how the soul sets about changing the course of bodies and
in fact tliis seems as inconceivable as saying that it gives
them motion, unless you have recourse, as I do, to pre-
established harmony. But the truth is that there is another
law of nature, which I have discovered and proved, and which
M. Descartes did not know: namely, that there is conserved not
only the same quantity of motive force, but also the same
quantity of direction from whatever side in the world it be
taken. That is to say: take any straight line you like, and
take also any number of bodies, chosen as you please; you
will find that, considering all these bodies together without
leaving out any of those which act on any of those which
you have taken, there will always be the same quantity of
progression from the same side in all the lines parallel to the
straight line you have chosen: provided care is taken that
the sum total of progression is estimated by deducting that
of the bodies which go in the opposite direction from that
of those which go in the direction chosen. This law is as
beautiful and as general as the other, and deserves as little
to be violated: and this is so in my system, which conserves
both force and direction, and, in a word, all the natural laws
of bodies, notwithstanding the changes which occur in
them as a result of those in the soul.

P.S. Hanover, 3/13 January 1696.

I see clearly from your reflections that I need to throw
some light on that idea of mine which a friend caused to be
inserted in the Journal de Paris. You say, sir, that you do
not see how I could prove what I propounded concerning
the communication or harmony of two substances as different
as the soul and the body. It is true that I thought I had
supplied the means of doing so. And I hope that what
follows will satisfy you.

Imagine two clocks or watches which are in perfect

THE NEW SYSTEM 115

agreement. Now this agreement may come about in three
ways. The first consists of a natural influence. This is what
M. Huygens tried with a result that surprised him. He
suspended two pendulums from the same piece of wood;
the continual strokes of the pendulums communicated
similar vibrations to the particles of the wood; but since
these different vibrations could not well persist independently
and without interfering with one another, unless the pen-
dulums were in agreement, it happened by some sort of
miracle that even when their strokes had been purposely
disturbed, they soon went back to swinging together, rather
like two strings l which are in unison. The second method
of achieving the constant agreement of two clocks, albeit
imperfect ones, would be to have them continually supervised
by a skilful craftsman who should be constantly setting
them right. The third method is to construct the two clocks
so skilfully and accurately at the outset that one could be
certain of their subsequent agreement.

Now substitute the soul and the body for these two watches.
Their agreement or sympathy will also arise in one of these
three ways. The way of influence is that of ordinary philo-
sophy; but as it is impossible to conceive of either material
particles, or immaterial species or qualities, as capable of
passing from one of these substances to the other, we are
obliged to abandon this view. The way of assistance is that
of the system of occasional causes. But I hold that this is
bringing in the dens ex machina for a natural and ordinary
thing, where reason requires it to intervene in the same way
only as it contributes to all other things in nature. Thus
there remains only my hypothesis, that it to say the way of
pre-established harmony pre-established, that is, by a Divine
anticipatory artifice, which so formed each of these substances
from the beginning, that in merely following its own laws,
which it received with its being, it is yet in accord with the
1 i.e. strings of a musical instrument.

n6 THE NEW SYSTEM

other, just as if they mutually influenced one another, or as if,
over and above His work of general co-ordination, God were
for ever putting in His hand to set them right. After this
I do not think there is anything for me to prove, unless I am
desired to prove that God possesses the cleverness necessary
for making use of this anticipatory artifice, of which we see
samples among men, in proportion as they are clever people.
And supposing that He can, it is clear that this is the finest
way and the worthiest of Him. You had some suspicion
that my explanation would be opposed to the rather different
idea we have of mind and body. But now you see clearly,
sir, that no one has better established their independence.
For so long as it was necessary to explain their communica-
tion by a kind of miracle, it was always left open to some
people to fear that the distinction between them might not
be what it was supposed to be, because it was necessary to
go to such lengths to uphold it. Now all these scruples
disappear. My Essays on Dynamics are connected with this ;
in them I had to inquire more deeply into the notion of bodily
substance, which on my view lies rather in the force of
acting and resisting than in extension, which is but a repeti-
tion or diffusion of something anterior, that is to say, of this
force. And as these thoughts of mine, which to some have
appeared paradoxical, have caused me to exchange letters
with various well-known men, I could produce a Commercium
Epistolicum on the subject, into which would come my
correspondence with M. Arnauld, of which I spoke in my
previous letter. It will contain a curious mixture of thoughts
about philosophy and mathematics, which will perhaps
sometimes have the charm of novelty. I leave you to judge,
sir, whether the explanations I have just given are suitable
for sounding the opinions of enlightened people through the
intermediary of your journal. But do not give my name, as
it was not given in the Journal de Paris either.

THE NEW SYSTEM 117

EXTRACT FROM A LETTER OF M. D. L. 1 REGARDING HIS
PHILOSOPHICAL HYPOTHESIS IN THE CURIOUS PROBLEM,
PROPOUNDED TO THE MATHEMATICIANS BY ONE OF HIS
FRIENDS, WITH AN EXPLANATION REGARDING SOME DIS-
PUTED POINTS IN PRECEDING ' JOURNALS ' BETWEEN THE
AUTHOR OF THE 'PRINCIPLES OF PHYSICS ' 2 AND THE
AUTHOR OF THE 'OBJECTIONS 1 . 3 1696

. . . Let me say 4 a word on the subject of the dispute between
two very clever people, the author of the Principles of Physics,
published recently, and the author of the Objections (included
in the Journal of i3th August and elsewhere), since my
hypothesis serves to end these controversies. I do not
understand how matter can be conceived as being extended,
and yet as being without parts either actual or mental. If
this be possible, I do not know what it is to be extended.
I even hold that matter is essentially an aggregate, and
consequently that it always has actual parts. Thus it is by
reason, and not only by the senses, that we judge that it is
divided, or rather that it is ultimately nothing but a plurality.
I hold that it is true that matter (and even each part of
matter) is divided into a greater number of parts than it is
possible to imagine. It is this that makes me often say that
each body, however small, is a world of created things infinite
in number. Thus I do not believe that there are atoms, that
is to say parts of matter which are perfectly hard, or in-
vincibly solid; just as on the other hand I do not believe
either that there exists matter which is perfectly fluid. My

1 M. D. L. is a pseudonym of Leibniz.

Nicolas Hartsoeker (1656-1725), a Dutch physicist, mainly
concerned with the making of microscopes and telescopes. His
correspondence with Leibniz about his philosophy of nature
is extant.

8 Foucher. Cf. p. 45, note.

4 The first part of this letter repeats the illustration of the two
clocks, given above; the second part deals with the solution of a
purely mathematical problem; the third part is given here.

n8 THE NEW SYSTEM

view is that each body is fluid in comparison with more solid
ones, and solid in comparison with more fluid ones. I am
surprised that it should still be said that there is always
conserved an equal quantity of motion in the Cartesian
sense; for I have proved the opposite, and already excellent
mathematicians have accepted my view. However, I do not
consider the hardness or consistency of bodies as a primary
quality, but as a consequence of motion, and I hope that
my Dynamics will show wherein this consists; just as the
understanding of my hypothesis will also serve to remove
several difficulties which still exercise philosophers. Indeed,
I believe I can answer intelligibly all the doubts to which the
late M. Bernier devoted a whole book, and those who are
ready to ponder what I have previously published will
perhaps already find therein the means of doing so.

EXPLANATION OF THE DIFFICULTIES WHICH M. BAYLE FOUND
IN THE NEW SYSTEM OF THE UNION OF THE SOUL AND
THE BODY

I take the liberty, sir, of sending you this explanation of
the difficulties which M. Bayle found in the hypothesis which
I suggested to explain the union of the soul and the body.
Nothing could be more accommodating than the manner in
which he has treated me in regard to it; and I consider myself
honoured by the objections which he included in his excellent
Dictionary, under the article ' Rorarius '. Moreover, so great
and profound a mind as his cannot make objections without
being instructive, and I will try to take advantage of the light
he has thrown on these questions, both here and in several other
places in his work. He does not reject what I said about the
conservation of the soul and even of the animal, 1 but he does
not yet appear to be satisfied by the way in which I claimed
to explain the union and intercourse between the soul and
the body, in the Journal des Savans of 27th June and 4th

H ft the whole animal nii1 anri hnriilv r>rea.nism.

THE NEW SYSTEM 119

July 1695, and in the Histoire des Outrages des Savans of
February 1696, pages 274 and 275.

These are his words, and they seem to show where it was
that he found difficulty: / am unable to understand (he says)
that necessary connection between internal and spontaneous
actions which would cause the soul of a dog to experience pain
immediately after having experienced joy, even though it were
alone in the universe. I answer, that when I said that the
soul would experience everything it now experiences, though
there were only God and itself in the world, I did but employ
a fiction, that is, I postulated what could not happen naturally
in order to make it clear that the feelings of the soul are
nothing but a consequence of what is already present in it.
I do not know whether M. Bayle means to demonstrate the
incomprehensibility of the necessary connection only in what
he says below, or whether he also intends to indicate it at
once by giving this example of the spontaneous transition
from joy to pain. Perhaps he wishes to give us to understand
that this transition is opposed to the axiom which teaches
that a thing remains always in the state in which it once is,
if nothing supervenes to cause it to change; and that there-
fore when an animal once feels joy, it will feel it always if
it is alone, and there is nothing outside it to cause it to
pass to pain. In any case, I remain in agreement with the
axiom, and even claim that it is favourable to me, as indeed
it is one of my fundamental principles. Is it not the case
that from this axiom we conclude, not only that a body that
is at rest will always remain at rest, but also that a body
that is in motion will always retain this motion or change,
that is to say the same velocity and the same direction, if
nothing supervenes to prevent it? Thus it is not simply
that in so far as depends upon itself a body remains in the
state in which it is, but also when it is in a state of change it
continues to change and this in accordance with the very
same law. Now according to me, it is the nature of created

120 THE NEW SYSTEM

substance to change continually following a certain order,
by which it is led spontaneously (if I may be allowed to use
this word) through all the states which are to happen to it,
so that He who sees everything sees in its present state all
its states both past and to come. And this law of order,
which constitutes the individuality of each particular
substance, has an exact relation to what occurs in every
other substance, and in the whole universe. Possibly I am
not making too bold a claim, if I say that I can prove all
this; but at the moment it is only a question of upholding
it as a possible hypothesis, and one fitted to explain the
phenomena. Now in this way the law governing the
changing of the substance of the animal bears him from joy
to pain, at the moment when there occurs in his body an
interruption of continuity, because the law of the indivisible
substance of this animal is to represent what occurs in his
body in the manner in which we experience it, and even to
represent in some fashion and in relation to this body every-
thing that occurs in the world; for the unities of substance
are nothing else but different concentrations of the universe,
represented according to the different points of view which
distinguish them.

M. Bayle continues: / understand why a dog passes im-
mediately from pleasure to pain when, after being famished and
eating bread, he is struck with a stick. I am not sure that
this is sufficiently well understood. No one knows better
than M. Bayle himself that just herein lies the great difficulty
we find in explaining why what happens in the body causes
a change in the soul ; and that it is just this which has driven
those who uphold occasional causes to have recourse to the
care that must be taken by God to see that all changes which
occur in a body shall be continually represented to its soul:
whereas I believe that it is its own nature, given it by God,
to represent to itself, by virtue of its own laws, what occurs
in its organs. He continues:

THE NEW SYSTEM 121

But that his soul is so constructed that at the moment when
he is struck he would feel pain even if he were not struck , but
were to continue eating bread without let or hindrance, that is
what I cannot understand. Neither do I recollect having
said so; nor could it be said except by a metaphysical fiction,
as when we suppose that God annihilates some body to
create a void, both suppositions being equally contrary to the
order of things. For since the nature of the soul was origin-
ally made in a manner fitted to represent to itself in succes-
sion the changes of matter, the supposed case could not
arise in the natural order. God could have given to each
substance its own phenomena independent of those of others,
but in this way He would have made, as it were, as many
unconnected worlds as there are substances; very much in
the same way as we say that when a man dreams, he is in his
own world apart, but that he enters the common world when
he wakes. It is not that dreams themselves are unrelated
to the organs and to the rest of the body, but that they are
related in a less distinct manner. Let us continue with
M. Bayle.

Further } the spontaneity of this soul (he says) seems to me
quite incompatible with feelings of pain, and in general, with
all perceptions which are not pleasing to it. This incompati-
bility would be certain if spontaneity and voluntariness
were the same thing. Everything which is voluntary is
spontaneous; but there are spontaneous actions which occur
without choice, and which consequently are not voluntary.
It does not rest with the soul to give itself always feelings
which are pleasing to it; for the feelings which it is going
to have are dependent on those which it has had. M.
Bayle proceeds:

Moreover, the reason why this gifted man does not fancy the
Cartesian system appears to me a false supposition, for it
cannot be said that the system of occasional causes makes the
action of God intervene by miracle (deus ex machina) in the

122 THE NEW SYSTEM

reciprocal dependence of the body and the soul: for as God does
not intervene except in accordance with general laws, His action
in this matter is not in any way out of the ordinary. It is not
for this reason alone that I do not fancy the Cartesian system;
and some slight consideration of my own doctrine will show
that I find in it positive reasons for adopting it. Even if the
hypothesis of occasional causes had no recourse to miracle,
it appears to me that mine would none the less possess
other advantages. I have said that three systems can be
imagined which might explain the communion between the
soul and the body; that is, (i) the system of the influence
of the one on the other, which is that of the Schools, taken
in the common sense this I agree with the Cartesians in
believing to be impossible; (2) the system of a perpetual
supervisor, who represents in the one what takes place in
the other, very much as if a man were entrusted with the
task of securing the agreement of two bad clocks, which
would not of themselves be capable of agreeing this is the
system of occasional causes; and (3) the system of the natural
agreement of two substances, such as would arise with two
very accurate clocks this system I hold to be as possible
as the system of the supervisor, and more worthy of the
Author of these substances, clocks, or automata. But now
let us see whether the system of occasional causes does not
in fact presuppose a perpetual miracle. M. Bayle says that
it does not, because according to this system God would not
act except through general laws. Granted, but on my view
this is not enough to obviate the miracles; even were God
to perform them continually, they would not cease to be
miracles, if we take this word not in the popular sense of a
rare and marvellous thing, but in the philosophical sense of
that which is beyond the powers of created things. It is not
enough to say that God made a general law; for besides the
decree there must also be a natural means of carrying it out;
that is to say, what occurs must be able to be explained by the

THE NEW SYSTEM 123

nature with which things are endowed by God. The laws
of nature are not so arbitrary or so indifferent as some
people believe. If, for example, God decreed that all bodies
should tend to move in circles, and that the radii of the
circles should be proportionate to the size of the bodies, we
should have either to say that there was a way of carrying
this out by means of simpler laws, or else to admit that God
brought it about miraculously, or at least by means of angels
expressly entrusted with the task, something like the angels
who in earlier times were supposed to be attached to the
celestial spheres. The same would be true if someone main-
tained that God had endowed bodies with natural and primary
gravities, by means of which each tended to move towards
the centre of its own sphere, without being impelled by other
bodies ; in my opinion this system would require a perpetual
miracle, or at least the assistance of angels.

Does the internal and active power which is communicated
to the forms of bodies know the sequence of actions which it will
produce? By no means ; for we learn from experience that we
do not know that we shall have such and such perceptions an
hour hence. I reply that this power, or rather this soul or
form itself, does not know them distinctly, but that it feels
them confusedly. There are in every substance traces of
everything that has happened to it and of everything that
will happen to it. But the infinite multitude of these per-
ceptions prevents us from distinguishing between them, in
the same way as when I hear a loud and confused noise made
by a crowd I am unable to distinguish one voice from another.

// would thus be necessary for these forms to be directed by
some external principle in the production of their actions; is not
this the deus ex machina again just the same as in the system
of occasional causes ? My foregoing answer shows that this
conclusion does not follow. On the contrary, the present
state of every substance is a natural consequence of its
preceding state, but only an infinite intelligence can grasp

124 THE NEW SYSTEM

this sequence for it involves the whole universe whether
in souls or in any given portion of matter.

M. Bayle concludes with these words: Finally, since he
supposes, and rightly so, that all souls are simple and indivisible,
it is impossible to understand how they can be compared to a
pendulum, that it to say that by their original constitution they
can vary their operations in utilizing the spontaneous activity
received from their Creator. It is quite clear that a simple
being will always act uniformly, if turned aside by no outside
cause. If it were composed of several parts like a machine, its
actions would show variety, because the particular activity of
each part might at any moment change the course of the activity
of the others ; but in a single substance, where will you find the
cause of a change of operation ? This objection I consider to be
worthy of M. Bayle : it is one of those which most deserve to
be elucidated. But I also believe that if I had not previously
provided for it, my system would not deserve to be examined.
I compared the soul to a pendulum only in regard to the
regulated exactitude of its changes, which is but imperfect
in the best of clocks, though perfect in the works of God; and
it may be said that the soul is an immaterial automaton of
the most exact kind. When it is said that a simple being
always acts uniformly, a distinction has to be made: if to
act uniformly is to follow perpetually the same law of order,
or of continuance, as in a given set or sequence of numbers,
I admit that of itself every simple being, and even every
compound being, acts uniformly; but if by uniformly is meant
similarly, then I do not agree. Let me explain the difference
of meaning by an example: a movement in a parabola is
uniform in the first sense, but not in the second, for the parts
of the parabola are not similar to one another, as are those
of a straight line. . . , 1

1 In the few lines here omitted Leibniz comments ' by the way '
on Bayle's statement that a simple body left to itself describes a
straight line. He points out that this is true if we consider only

THE NEW SYSTEM 125

We must also remember that the soul, simple though it is,
has always a sensation which is composed of several percep-
tions at once; and this serves the purpose for my theory as
much as if it were composed of parts, like a machine. For
each preceding perception has some influence on those which
follow, in conformity with a law of order which is to be found
in perceptions as well as in motions. Moreover, the majority
of philosophers, for several centuries, who have endowed
with thoughts both souls and angels (whom they hold to be
destitute of all body), not to mention the intelligences of
Aristotle, admit the occurrence of spontaneous change in a
simple being. I add that, since the perceptions which exist
together in the same soul at the same time include a truly
infinite multitude of small feelings, indistinguishable from
one another, which the future will develop, we must not be
surprised at the infinite variety of what must result from
them in the course of time. All this is but a consequence
of the representative nature of the soul, which is bound to
express everything that is occurring and even everything
that is going to occur in its own body, and in some manner
in all other bodies, owing to the connection or correspondence
between all the parts of the world. It would perhaps have
been enough to say that since God has made corporeal
automata, He could easily likewise have made immaterial
ones to represent them; but I thought it would be well to
develop this matter a little further.

For the rest, I have read with pleasure what M. Bayle says
in the article 'Zeno*. Perhaps he will notice that what can
be derived from it agrees better with my system than with
any other; for whatever is real in extension and in motion

the centre of the body; but in the case of a rotating body, a point
in it distant from the centre describes a circle when the centre is
stationary, and a more complicated curve (of which Leibniz
gives the co-ordinates) when the centre is moving in a straight
line. But he does not press this mathematical point into
service for his general argument here.

126 THE NEW SYSTEM

consists only in the foundation of the order and regulated
sequence of phenomena and perceptions. The Academics
and the Sceptics, no less than those who wished to reply to
them, seem to have been in difficulties only because they
sought a greater reality in the sensible things outside us than
the reality of regulated phenomena. We conceive of ex-
tension, by conceiving an order in co-existences; but we
ought not to conceive of it, nor ought we to conceive of space
after the manner of a substance. It is like time, which
presents to the mind nothing but an order among changes.
And as to motion, what is real in it is the force or power,
that is to say, that which in the present state carries with
it a change for the future. The rest is but phenomena
and relations.

The consideration of this system shows also that when we
go deeply into things, we find more sound sense than we
thought in the majority of philosophical sects. . . .

REMARKS UPON THE ARTICLE 'RORARIUS' IN M. BAYLE'S
DICTIONARY

i. My first comment * is that M. Leibniz exalts beyond any-
thing that can be conceived the power and intelligence of Divine
art. I agree that he exalts it beyond anything that can be
understood, but not beyond anything that can be conceived.

Imagine a ship having neither feeling nor knowledge, and with
no being created or uncreated at the helm, to have the power to
move itself of its own nature so skilfully that it always enjoys a
favourable wind, avoids currents and shallows, and finds a
haven just at the right moment. Suppose such a ship sailing
thus for several years continuously, always turned in the very
direction and situated in the very place required by the changes
of atmosphere and the different situations of land and sea;

1 Italics indicate quotations from Bayle's Dictionary. From
this paper an extract only is given here.

THE NEW SYSTEM 127

you will agree that the infinitude of God is not greater than
is necessary to endow a ship with such a faculty, and you
will even say that a ship's nature is not capable of receiving
this power from God. Yet what M. Leibniz supposes regarding
the machine of the human body is more wonderful and more
surprising than all this.

I will first reply to the question whether the supposition
of such a ship is possible. And afterwards I will come to the
comparison here made with the machine of the human body.
In the first place I find it strange that M. Bayle should dare
to decide the question in the negative, and to deny that this
is possible to God, without adducing any reason, when he
himself often agrees that anything which does not imply a con-
tradiction or imperfection could be produced by the Divinity.
I admit that M. Bayle would be right if God were being
required to endow the ship with some faculty, perfection, or
occult quality, by which it could of itself direct its own
course, without any knowledge within itself and without any
attraction or direction from without, like the Phaeacians*
vessel in Homer's Odyssey. For such a supposition would be
impossible, and would violate the principle of sufficient
reason, since it would be impossible to give any explanation
of such a perfection, and God would always have to be setting
His hand to it by a perpetual miracle unless some occasion-
alist thought it suitable to have recourse to his supposed
general laws, since God might promulgate one in favour of
this ship; nor could M. Bayle, who is anxious to divorce
occasional causes from miracles, reasonably object to this.
For myself, I reject these natural laws exemption from which
is absolutely explicable by the nature of things. But while
we reject this occult quality in the ship, we must admit that
there is nothing to prevent there being a ship, born under a
lucky star as it were, so that it always reaches port, without
guidance by the winds and tides, through storms and shallows,
simply by encountering favourable accidents, Certain it is
L95

128 THE NEW SYSTEM

that ships without men have sometimes reached their
destined shore. Is there anything that makes it impossible
for this to happen several times to the same ship, and con-
sequently as many times as it puts to sea which will only
happen a certain number of times? Since the number of
accidents is not infinite, not only God but even an exceedingly
excellent finite spirit would be able to foresee all the accidents
to which the ship would be exposed, and could find out by
solving a geometrico-mechanical problem the structure of the
ship and the places, times, and methods of its putting to sea
which would make it adjust itself in the best way to this
finite number of accidents. Do we not know that men are
sufficiently skilful to make automata capable of turning at
a specified place at street corners, and of adjusting them-
selves in this way to a certain number of accidents? And
a Mind proportionally greater would provide against accidents
in greater numbers. And if this excellent Mind did not find
these accidents already given, but was free to make them
arise or cease at His will, it would be incomparably easier
still for Him to satisfy this demand, and to adjust in advance
and by a pre-established harmony the ship to the accidents
and the accidents to the ship. Thus it is the gravest mistake
to doubt whether the infinity of God is great enough to be
able to succeed in this.

2. Let us apply to the person of Caesar the new system of the
union of the soul and the body: according to this system we must
say that the body of Julius Caesar exercised its motive power in
such a way that from birth to death it followed a constant pro-
gression of changes which corresponded in the last degree of
exactness to the perpetual changes of a particular soul which
the body did not know, and which made no impression on it.

Bodies do not know what takes place in the soul, and the
soul makes no physical impression on the body. M. Bayle
agrees with this; but God has supplied this lack not by Him-
self giving the body at intervals new impressions to make it

THE NEW SYSTEM 129

obey the soul, but by making this automaton such in the
first place that it will carry out what the soul commands
punctually as to both time and place.

We must say that the ride according to which this faculty of
Caesar's body had to produce these actions was such that he
would have gone to the Senate on such a day and at such an
hour, that he would there have uttered such and such words , etc.,
even though it had pleased God to annihilate Caesar's soul the
day after it was created.

There is nothing strange in this when once we bear in mind
that as great a craftsman as God can make an automaton
which resembles a valet and is capable of performing his
function, and of carrying out at a specified place whatever
it was ordered to do over a long period of time. The body
is an automaton of this kind in regard to the mind.

We must say that this motive power punctually changed
itself and modified itself in accordance with the volubility of the
thoughts of that ambitious spirit, and that it assumed precisely
such a particular state rather than any other, because the soul
of Caesar passed from one particular thought to another.

It seems that M. Bayle has let himself be deceived, for
he has imagined that the ship of the man's body was endowed
with some mysterious faculty or power capable of adjusting
itself to the accidents or the thoughts without having any
knowledge of them, and even without any intelligible reason.
He is entirely justified in condemning such a faculty as
impossible, but no one ever thought of such a thing. All that
the automaton which played the valet would need would be
a structure which would make it perform its functions by
virtue of the rules of mechanics. It would not modify itself
nor change itself to adjust itself to the thoughts of its master.
It would follow its own course, and by that very means
would exactly fall in with the will of him whom the craftsman
who made it meant it to serve.

Can a blind force so conveniently modify itself as the result

130 THE NEW SYSTEM

of an impression conveyed 30 or 40 years previously ', and never
since renewed, and which has moreover been left to itself without
ever having any knowledge of its lesson ? Is this not much more
incomprehensible than the navigation of which I spoke in the
preceding paragraph ?

It becomes clearer and clearer that M. Bayle has not
properly grasped my view, which is that the body modifies
itself in the required way not by some kind of impression
or power it has received, but by its own structure, which is
adjusted to that end. The automaton which plays the valet
will again serve to remove the whole difficulty. The struc-
ture with which it has been endowed suffices for all its
functions, even if it is left to itself, even if its first impressions
are not renewed, and even if it has no knowledge of the
command or of the lesson given to it. And the difference
between the body of Caesar and tfiis automaton is but the
difference between the greater and the less. 1

4. // is vain for upholders of the view that the brutes are
nothing but automata to shelter themselves behind the power of
God. It is vain to explain that God was able to construct
machines, so artfully wrought that the voice of a man, the
reflected light of an object, etc., strike them in precisely the right
place so that they move in such and such a way. Every one,
except a few of the Cartesians, rejects this siipposition.

It is rejected not as impossible but as unlikely.

And there is no Cartesian who would accept the view if it
were extended to man, that is to say if it were maintained that

1 Bayle points out (in 3, which is omitted here) that the
changes which occur in the soul, corresponding to all the actions
and interactions between the organs of the body and between
the body and other bodies, are infinite in number, and urges
that this infinity makes the theory of a pre-established harmony
between spontaneous unities quite incredible. Leibniz replies
that the fact that the variety of changes is infinite does nothing
to increase the difficulty; it only gives ground for 'wondering
still further at the Divine artifice '.

THE NEW SYSTEM 131

God was able to make bodies which could perform mechanically
all the things that we see other men do.

The Cartesian will not deny that it is possible for God to
make such an automaton; but he will not allow that other
men are in fact inanimate automata of this kind. He will
think, and rightly, that they are like himself. According to
my view, all alike are automata, the bodies of men as well as
those of brutes, but all of them are animated, the bodies of
brutes as well as those of men. Thus pure materialists, such
as the followers of Democritus, no less than formalists, such
as the Platonists and Peripatetics, are right in some things,
and wrong in others. There is a great deal of justification
for the view of the followers of Democritus that the bodies of
men as well as those of brutes are automata and perform all
their actions mechanically; but they were wrong in thinking
that these machines were not accompanied by an immaterial
substance or form, and that matter was capable of perception.
The Platonists and the Peripatetics held that brutes and men
have animated bodies, but they were wrong in thinking that
souls change the rules of the motion of bodies; thus they
denied the automatism of the body of both brute and man.
The Cartesians were right to reject this influence, but they
were mistaken in denying automatism to man and sensation
to brutes. I hold that we must allow both to both men and
brutes, that we must follow Democritus in making all the
actions of mechanical bodies independent of souls, and that
we must also go further than the Platonists in holding that
all the actions of souls are immaterial and independent of
the machine.

In denying this we do not claim to set limits to the power and
knowledge of God. We simply mean that the nature of things
requires that the powers given to the created being should
necessarily have certain limitations. It is absolutely necessary
that the activity of created things should be proportioned to their
essential state , that it should be exercised in accordance with the

132 THE NEW SYSTEM

character which is fitted to the given machine ; for according to
the axioms of the philosophers everything which is received is
proportioned to the capacity of the subject.

M. Bayle keeps on reverting to this supposed power given
to the body to enable it to accommodate itself to the soul.
I do not require any such thing; I do not go outside the
limitations of created things, nor of the state of bodies or
machines. There is nothing in the artifice of the Divine
machine which surpasses the knowledge and the power of
God. Since He knows everything which can be known, and
can do everything which can be done, He knows the number
(which is limited) of the volitions of man: and He has the
ability to make a machine capable of carrying them out.

We may therefore reject as impossible M. Leibniz's hypothesis,
since it involves greater difficulties than that of automatism.

This argument would be good if the theory of automata
had been convicted of impossibility, but since the contrary
is manifest and has been sufficiently proved by the Cartesians,
it is only a question of greater and less, which involves no
difficulty when it is a question of a power and a wisdom which
are infinite. Although man reasons about matters which
are abstract and which surpass the imagination, he none the
less has in his imagination signs which correspond to them,
such as letters and characters. There is no understanding
so pure as not to be accompanied by some imagination.
Thus there is always in the body something mechanical which
corresponds exactly to the sequence of thoughts present in a
man's mind, in so far as that which can be imagined enters
into the matter, and consequently the automaton of his body
has no more need of the influence of the soul, or of the
supernatural assistance of God, than has that of the brute's
body.

It maintains the existence of a continual harmony between
two substances which do not act on one another.

Why not? since they originate from one and the same

THE NEW SYSTEM 133

Author who was willing and able to arrange that they should
agree without acting on one another.

But if the valets were machines, and punctually performed
this and that whenever their master commanded, such a thing
could only be if the master really acted on them : he would utter
words and would make signs which would really affect the organs
of the valets.

But there are valets who are so well trained as not to need
signs to be given to them. They anticipate them. Watches
which strike, for instance, and alarm clocks are valets of this
kind. Far from awaiting signs, they give them to us. The
artificial valet, who imitates and counterfeits a real one, such
as we have been speaking of above, does not even need to be
wound or set by us, as do watches and alarm clocks. The Arti-
ficer would have prepared him for us. Such a valet is our body.

5. If we consider at this point the soul of Caesar, we shall
find still more impossibilities. This soul was in the world
without being exposed to the influence of any body or of any
mind. The force it had received from God was the sole principle
of the particular actions it produced at each moment ; and if
these actions were different one from another, this was not due
to the fact that some were produced with the co-operation of
certain sources of action, which did not contribute to the pro-
duction of the others ; for the soul of man is simple, indivisible,
and immaterial. M. Leibniz agrees ; and if he did not agree,
but on the contrary was at one with the majority of the philoso-
phers and even with some of the greatest metaphysicians of our
age (Mr. Locke for example) in supposing that a thing composed
of several material parts arranged in a certain way is capable
of thinking, I should in that case regard his hypothesis as
absolutely impossible,

(So M. Bayle does not yet regard it as impossible.)
and many other ways of refuting it would present themselves,
which are here no concern of mine, since he does recognize the
immateriality of the soul, and builds upon it.

134 THE NEW SYSTEM

To say that the force which the soul has received from
God is the sole principle of its particular actions does not
afford sufficient explanation of its actions. It is better
to say that God has placed in every soul a concentration of
the world, or the power of representing the universe from a
point of view proper to that soul, and that it is this that
is the principle of its actions, distinguishing them from one
another and from the actions of another soul. For it follows
that they will continually be undergoing changes representa-
tive of the changes in the universe, and that the other souls
will undergo other changes, but corresponding ones.

Let us return to the soul of Caesar, and let us call it an im-
material automaton, to use M. Leibniz's own expression ; and let
us compare it with an Epicurean atom. I mean an atom which
is surrounded by a void on all sides and which will never meet
any other atom. The comparison is a very just one ; for on
the one hand this atom has a natural faculty of moving itself,
and exerts it without being helped by anything whatever,
and without being checked or deflected by anything at all; and
the soul of Caesar is a mind which has the power of giving
itself thoughts, and which exerts it without being influenced by
any other mind, or by any body. Nothing assists it, nothing
deflects it. If you consult common notions and common ideas
of order you will find that this atom must never stop, and that
having moved in the preceding moment, it must move in the
present moment and in all subsequent moments, and that the
manner of its motion must always be the same. This is a
consequence of an axiom approved by M. Leibniz. From the
fact that a thing remains always in the state in which it once
is, if nothing supervenes to cause it to change, we conclude (he
says) not only that a body which is at rest will always remain
at rest; but also that a body which is in motion will always
retain this motion or change, that is to say the same velocity
and the same direction, if nothing supervenes to prevent it.
All the world knows clearly that this atom, whether it moves by

THE NEW SYSTEM 135

an innate faculty, as Democritus and Epicurus assure us, or
whether it moves by a faculty received from the Creator, always
proceeds uniformly and equally in the same line without its ever
happening to it to turn to right or to left or to turn back. Epicurus
was made fun of when he invented the motion of atomic 'swerve';
he postulated it gratuitously to get himself out of the labyrinth
of the fatal necessity of all things, and he could give us no reason
for this new part of his hypothesis. It offended against the
most obvious notions of our minds, for it is evident that if an
atom which has pursued a straight line for two days is to turn
aside from its route at the beginning of the third day it must
either encounter some obstacle, or conceive some desire of leaving
its path, or else contain some source of energy which becomes
active at that moment. The first of these reasons does not arise
in empty space, the second is impossible because an atom has
not the power of thought; the third is likeioise impossible in a
body which is absolutely one.

Before proceeding, it is well to point out a great difference
between matter and the soul. Matter is an incomplete
being: it lacks the original source of actions. And when it
receives an impression, that impression precisely, and what
is in it at the moment, is all that the matter contains. It is
for this reason that matter is not even capable of maintaining
of itself a circular motion, for this motion is not sufficiently
simple for it to be able to remember it, so to speak. It
remembers only what happens to it in the last moment, or
rather in ultimo signo rationis, 1 that is to say it remembers
the direction straight along the tangent, without having the
gift of remembering the instruction which would be given
to it to turn aside from that tangent, to make it remain all
the time on the circumference. This is why the body does
not maintain its circular motion, even though it has begun
such a motion, unless there is some reason compelling it to
do so. This is why an atom can only learn to go simply
1 'in the last stage in the order of reasoning*.

136 THE NEW SYSTEM

in a straight line, such is its stupidity and imperfection.
The case is quite different with a soul or mind. As it is a
true substance or complete being, which is the original
source of its own actions, it remembers as it were (confusedly,
of course) all its preceding states, and is affected by them.
It not only holds its direction, as does the atom, but it holds
also the law of the changes of direction, or the law of curves,
which the atom is incapable of doing; and whereas in the
atom there is but a single change, there is an infinite number
of changes in the modifications of the soul, each of which
holds its own law; for the Epicurean atom, although endowed
with parts, is a thing internally united, whereas the soul,
although it has no parts, contains within itself a great
number, or rather an infinite number, of varieties, owing to
the multitude of the representations of external things, or
rather owing to the representation of the universe, which the
Creator placed in it. If M. Bayle had considered this dif-
ference between the conatus of bodies and of souls, of which I
had already some slight notion in my earliest youth, when I
gave to the public my Physical Hypothesis (an idea which
impressed the late M. Lantin of Dijon, as is proved by a
letter he wrote me) he would not have brought up against me
the comparison of an Epicurean atom with the human soul,
as he does here.

6. Let us make some use of all this. The soul of Caesar is
a being to which the term unity is in the strictest sense applicable.
The power of giving itself thoughts is a property of its nature,
according to the system of M. Leibniz. It received it from
Gody both as regards its possession and as regards its exercise.
If the first sensation which it gives itself is a sensation of
pleasure,

(I do not conceive that the soul gives itself first sensations.
It received them from God with its being at the moment of
creation, since it had some at the outset; and in its first
sensations it received virtually all the rest.)

THE NEW SYSTEM 137

it is not easy to see why the second thought also should not be
a sensation of pleasure; for when the total cause of an effect
remains the same, the effect cannot change.

The total cause does not remain the same in this case.
Present thoughts include a tendency to other thoughts.
For the soul does not only have perception, but has appetite
as well. But in tending towards new pleasures it sometimes
encounters pains.

Now this soul at the second moment of its existence does not
receive a new power of thinking, it merely retains the power
which it had in the first moment, and is as independent of the
impact of every other cause in the second moment as in the
first; it must therefore reproduce in the second moment the same
thought that it has produced just before.

Not at all; because it tends towards change in accordance
with the laws of appetite, as body tends towards change in
accordance with the laws of motion.

If you object that it must be in a state of change, and that it
would not be so in the case that I have supposed, I answer that
its changing will be similar to the changing of the atom. For
an atom which moves continually along the same line acquires
at each moment a situation which is new but similar to its
preceding situation. In order, therefore, that the soul may
persist in its state of change, it is enough that it should produce
a new thought similar to the preceding one.

I have already explained above the great difference there
is between the laws of change of a body, such as the atom,
and those of the soul. And the very difference between the
thought of the soul and the motion of the atom is evidence
of this. Spontaneous motion consists in the tendency to
move in a straight line; there is nothing which is so unified.
But thought implies an actual material object, which is the
human body; and this object is compound, and contains a
very great number of modifications, whereby it is attached
to the surrounding bodies, and by means of them in varying

I 3 8 THE NEW SYSTEM

degree to all other bodies. And the tendencies of the soul
towards new thoughts correspond to the tendency of the
body towards new shapes and new motions. And as these
new motions are capable of causing the object to pass from
order to disorder, so their representations in the soul are
capable of causing the soul to pass from pleasure to pain.
Let us not press this point too rigidly; let us grant a metamor-
phosis of thoughts. At the very least it would be necessary
that the passage from one thought to another should include
some ground of affinity. If I suppose that at a particular
instant the soul of Caesar is looking at a tree which has flowers
and leaves, I can conceive (if we assume that a created mind
can give itself ideas, notwithstanding those reasons which
prevent our understanding it) that his soul might immediately
wish to see a tree which has only leaves and then another which
has only flowers; and that thus it will produce for itself in
succession several images which will arise one from another.
But we cannot represent as possible changes from white to
black, and from yes to no, nor the wild leaps from earth to shy
which are common in the thought of man. We cannot believe
that God was able to put into the soul of Julius Caesar the
principle of what I am about to say. It no doubt happened
to him on several occasions that when sucking he was pricked
by a pin. It was therefore necessary (on the hypothesis we are
here examining) for his soul to modify itself by a feeling of pain
immediately after the pleasant perceptions of the sweetness
of the milk 9 which it had experienced for two or three minutes
in succession. By what source of energy was it forced to inter-
rupt its pleasures, and to give itself suddenly a feeling of pain,
when nothing had warned it to prepare for the change, and
when nothing new had taken place in the substance? If you
run through the life of this first Emperor you will find at every
step material for a stronger objection than this one.

Let us run through this statement. It is certainly true
that the passage from one thought to another must include

THE NEW SYSTEM 139

some link or reason, and this has been shown. If Caesar's
soul had nothing but distinct thoughts, and gave them all to
itself voluntarily, the passage from one thought to another
might be like what M. Bayle suggests of the passage from one
tree to another, for example. But besides the perceptions
which the soul remembers, it has a heap of an infinite number
of confused ones which it does not disentangle; and it is by
these that it represents the bodies outside itself, and that it
arrives at distinct thoughts dissimilar to the preceding ones
because the bodies which it represents have passed suddenly
to something which powerfully affects its own body. Thus
the soul sometimes passes from white to black, or from yes
to no, without knowing how, or at least in an involuntary
manner. For what its confused thoughts and its sensations
produce in it, is attributed to the bodies. It is not surprising,
therefore, if a man who is eating jam and feels himself stung
by an insect, passes immediately from pleasure to pain in
spite of himself. For the insect was already affecting the
man's body by getting near him before stinging, and the
representation of this already affected his soul, albeit in-
sensibly. Little by little, however, what is insensible
becomes sensible, in the soul as in the body; this is how it
happens that the soul modifies itself against its own inclina-
tion, for it is the slave of its feelings and of its confused
thoughts which arise in accordance with the states of its own
body and of other bodies in relation to its own. Here then
are the sources of energy by which pleasures are sometimes
interrupted and succeeded by pains, without the soul always
having warning or being prepared, as for example when the
stinging insect approaches us noiselessly, or else, if for instance
it is a wasp, some distraction prevents our noticing its buzzing
as it approaches. Thus it must not be said that nothing new
has taken place in the substance of the soul, to make it arrive
at the feeling of the sting; it is the confused presentiments,
or, to put it more strictly, the insensible dispositions of the

140 THE NEW SYSTEM

soul which represent the dispositions to the sting in the
bodies.

7. We might understand something of all this if we suppose
that the soul of man is not a mind but rather a legion of minds,
each of which has its functions which begin and end precisely
as required by the changes occurring in the human body. As
a consequence of this we should have to say that something
analogous to a great array of wheels and springs or of portions
of matter in agitation, arranged in accordance with the vicis-
situdes of our machine, awakened or put to sleep for such and
such a time the activity of each of these minds; but in that
case the soul of man would no longer be a substance, it would
be an ens per aggregationem, an aggregate and a pile of
substances, just like material things. What we are looking for
here is one single thing which produces sometimes joy, sometimes
pain, etc.; we are not looking for several things, of which one
produces hope, another despair, and so on.

M. Bayle is right to reject this view of the compound
nature of the soul, for it would make it capable of destruction
and dissipation since it would be an aggregate. But my
theory does not require that the substance of the soul should
be compound ; it is enough if its thoughts are compound and
embrace a large number of objects and modifications which
are known distinctly or confusedly; and this experience
teaches us to be actually the case. For although the soul is
a simple and single substance, it never has perceptions which
are simple and single. It always has, at one and the same
time, a number of distinct thoughts which it can remember,
and attached to these an infinity of confused thoughts, whose
ingredient parts it cannot distinguish. Since this complex
of thoughts only has to produce other compound thoughts,
it has no need of any legion of minds. Each partial modi-
fication of the preceding state of the soul contributes to the
subsequent total modification of the same soul, and gives it
a new variation.

NEW ESSAYS ON THE HUMAN UNDERSTANDING

INTRODUCTION

SINCE the Essay on the Human Understanding, by a famous
Englishman, 1 is one of the finest and most highly esteemed
works of our time, I have resolved to make some remarks on
it, because, having long meditated on the same subject and
on the greater part of the matters therein considered, I
thought this would be a good opportunity for publishing
something under the title of New Essays on the Human
Understanding, and for securing a favourable reception for
my reflections by putting them in such good company. I
further thought that I might profit by someone else's labour,
not only to dimmish my own (since in fact it is less trouble
to follow the thread of a good author than to work at every-
thing afresh), but also to add something to what he has.
given us, which is always an easier task than making a start;,
for I think I have removed certain difficulties which he had
left entirely on one side. Thus his reputation is of advantage-
to me; and since I am moreover inclined to do justice to him x ,
and am very far from wishing to lessen the high opinion
commonly entertained of his work, I shall increase his

1 John Locke (1632-1704). When his Essay was published in
1690 Leibniz sent him some short papers in criticism. Locke
seems to have paid little attention to these. In 1700, Coste's
translation of the Essay into French was published, and Leibniz
set himself to write the New Essays, an elaborate work in which
he examines and criticizes Locke's doctrines in a running com-
mentary; he delayed publication, however, as a new edition of
the French translation of the Essay was promised. Then in
1704 Locke died; and the New Essays were not published until
1 765, nearly fifty years after the death of Leibniz.

141

142 LEIBNIZ AND LOCKE

reputation if my approval has any weight. It is true that
1 am often of another opinion from him, but, far from denying
the merit of famous writers, we bear witness to it by showing
wherein and wherefore we differ from them, since we deem it
necessary to prevent their authority from prevailing against
reason in certain important points; besides the fact that, in
convincing such excellent men, we make the truth more
acceptable, and it is to be supposed that it is chiefly for
truth's sake that they are labouring.

In fact, although the author of the Essay says a thousand
fine things of which I approve, our systems are very different.
His bears more relation to Aristotle, mine to Plato ; although
we both of us depart in many things from the doctrine of
these two ancient philosophers. He is more popular, while
I am sometimes compelled to be a little more acroamatic and
abstract, which is not an advantage to me, especially when
writing in a living language. But I think that by making
two characters speak, of whom one expounds the views
derived from our author's Essay* while the other gives my
observations, I shall show the relation between us in a way
that will be more to the reader's taste than dry remarks, the
reading of which would have to be constantly interrupted by
the necessity of referring to his book in order to understand
mine. Nevertheless it will be well sometimes to compare our
writings and to judge of his opinions by his own work only,
although I have as a rule retained his expressions. It is true

1 Philalethes gives Locke's views, and Theophilus those oJ
Leibniz. The words of Philalethes are sometimes obviously a
translation of Locke's own words, sometimes a paraphrase 01
summary of a particular passage in Locke, and sometimes a
free re-statement of Locke's doctrine. Where his words art
obviously meant to be a translation, instead of retranslating
them I have printed Locke's own words in italics, as it may be ol
advantage to the reader to see at a glance what is the origina
Locke, and what is Leibniz's summary or re-statement. Ir
some places of course it is difficult to tell whether to treat the
French as translation or as paraphrase; but as a general rule
it is clear enough.

LEIBNIZ AND LOCKE 143

that the necessity of having to follow the thread of another
person's argument in making my remarks has meant that I
have been unable to think of achieving the graces of which
the dialogue form is capable: but I hope the matter will make
up for this defect in the manner.

Our differences are on subjects of some importance. The
question at issue is whether the soul itself is entirely void,
like a tablet whereon nothing has yet been written (tabula
rasa), as is the view of Aristotle and the author of the Essay,
and everything marked on it comes solely from the senses and
from experience, or whether the soul contains originally the
principles of various notions and doctrines, which external
objects simply recall from time to time, as is my view and
that of Plato, and even of the Schoolmen, and of all those
who attribute this meaning to the passage from St. Paul
(Rom. ii 15), where he says that the law of God is writ in
men's hearts. The Stoics call these principles prolepses, that
is to say assumptions which are fundamental or taken as
agreed in advance. The mathematicians call them common
notions (Koival eWoiac). Modern philosophers give them
other fine names, and Julius Scaliger in particular called
them semina aeternitatis 1 and again zopyra, meaning to say
living fires, flashes of light, hidden within us, but caused
to appear by the contact of the senses, like the sparks which
the shock of the flint strikes from the steel. And it is not
an unreasonable belief that these flashes are a sign of some-
thing divine and eternal, which makes its appearance above
all in necessary truths. From this arises another question,
whether all truths depend on experience, that is to say on
induction and on instances, or whether there are some which
have another basis also. For if certain events can be fore-
seen before we have made any trial of them, it is clear
that we contribute in those cases something of our own.
The senses, although they are necessary for all our actual

1 ' seeds of eternity '.
M95

144 LEIBNIZ AND LOCKE

knowledge, are not sufficient to give us the whole of it, since
the senses never give anything but instances, that is to say
particular or individual truths. Now all the instances which
confirm a general truth, however numerous they may be, are
not sufficient to establish the universal necessity of this same
truth, for it does not follow that what happened before will
happen in the same way again. For example, the Greeks
and the Romans, and all the other peoples of the earth known
to the ancients, always observed that before the passage of
twenty-four hours day changes to night and night to day.
But they would have been wrong if they had believed that
the same rule holds good everywhere, for since that time the
contrary has been experienced during a visit to Nova Zembla.
And any one who believed that in our zone at least this is a
necessary and eternal truth which will last for ever, would
likewise be wrong, since we must hold that the earth and
even the sun do not exist of necessity, and that there may
perhaps come a time when that beautiful star and its whole
system will exist no longer, at least in its present form.
From which it appears that necessary truths, such as we
find in pure mathematics, and particularly in arithmetic
and geometry, must have principles whose proof does not
depend on instances, nor consequently on the testimony of
the senses, although without the senses it would never have
occurred to us to think of them. This is a distinction that
should be carefully noted ; and it is one which Euclid under-
stood so well that he often proves by reason what is evident
enough through experience and sensible images. Logic also,
together with metaphysics and morals, the one of which
forms natural theology and the other natural jurisprudence,
are full of such truths; and consequently proof of them can
only arise from inner principles, which are called innate. It
is true that we must not imagine that we can read in the soul
these eternal laws of reason as in an open book, as the edict
of the praetor can be read in his album without trouble or deep

LEIBNIZ AND LOCKE 145

scrutiny. But it is enough that we can find them in ourselves
by dint of attention, opportunities for which are afforded by
the senses. The success of experiments serves also as a
confirmation of reason, more or less as verifications serve in
arithmetic to help us to avoid erroneous calculation when the
reasoning is long. It is in this also that the knowledge of
men differs from that of the brutes: the latter are purely
empirical, and guide themselves solely by particular instances ;
for, as far as we can judge, they never go so far as to form
necessary propositions; whereas men are capable of the
demonstrative sciences. This also is why the faculty the
brutes have of making sequences of ideas is something inferior
to the reason which is in man. The sequences of the brutes
are just like those of the simple empiricists who claim that
what has happened sometimes will happen again in a case
where what strikes them is similar, without being capable
of determining whether the same reasons hold good. It is
because of this that it is so easy for men to catch animals, and
so easy for pure empiricists to make mistakes. And people
whom age and experience has rendered skilful are not
exempt from this when they rely too much on their past
experience, as some have done in civil and military affairs;
they do not pay sufficient attention to the fact that the
world changes, and that men become more skilful by dis-
covering countless new contrivances, whereas the stags and
hares of to-day are no more cunning than those of yesterday.
The sequences of the brutes are but a shadow of reasoning,
that is to say, they are but connections of imagination,
transitions from one image to another; for in a fresh ex-
perience which appears like the preceding one, there is the
expectation that what was hitherto joined thereto will occur
again, as though the things were connected in fact, because
their images are connected in the memory. It is true that
reason also teaches us to expect in the ordinary course of
events to see occur in the future what conforms to a long

146 LEIBNIZ AND LOCKE

experience of the past, but it is not therefore a necessary and
infallible truth, and we may cease to be successful when we
least expect it, when the reasons which have maintained it
change. This is why the wisest people do not rely on it to the
extent of not trying to discover, if it is possible, something
of the reason of what happens, so as to judge when exceptions
must be made. For reason alone is capable of setting up
rules which are certain, and of supplying what is lacking to
those which are not certain, by inserting the exceptions, and
in short of finding connections which are certain in the force
of necessary consequences. This often provides the means
of foreseeing the event, without its being necessary to ex-
perience the sensible connections between images which is
all that the brutes can do; so that to vindicate the existence
within us of the principles of necessary truths is also to
distinguish man from the brutes.

Perhaps our gifted author will not entirely dissociate
himself from my opinion. For after having devoted the
whole of his first book to the rejection of innate ideas, under-
stood in a certain sense, he yet admits in the beginning of the
second and in what follows that ideas whose origin is not in
sensation arise from reflection. Now reflection is nothing
but an attention to what is in us, and the senses do not give
us what we already bring with us. This being so, can we
deny that there is a great deal that is innate in our mind,
since we are innate, so to speak, to ourselves, and since there
is in ourselves being, unity, substance, duration, change,
activity, perception, pleasure, and a thousand other objects
of our intellectual ideas? And since these objects are im-
mediate to our understanding and are always present (al-
though they cannot always be apperceived on account of our
distractions and our needs), why be surprised that we say that
these ideas, and everything which depends on them, are
innate in us? This is why I have taken as an illustration a
block of veined marble, rather than a wholly uniform block

LEIBNIZ AND LOCKE 147

or blank tablets, that is to say what is called tabula rasa in
the language of the philosophers. For if the soul were like
these blank tablets, truths would be in us in the same way as
the figure of Hercules is in a block of marble, when the marble
is completely indifferent whether it receives this or some other
figure. But if there were veins in the stone which marked
out the figure of Hercules rather than other figures, this
stone would be more determined thereto, and Hercules
would be as it were in some manner innate in it, although
labour would be needed to uncover those veins, and to clear
them by polishing, and by cutting away what prevents them
from appearing. It is in this way that ideas and truths arc
innate in us, like natural inclinations and dispositions, natural
habits or potentialities, and not like activities, although these
abilities are always accompanied by some activities which
correspond to them, though they are often imperceptible.
It seems that our gifted author claims that there is in us
nothing potential, nor even anything which we do not always
actually apperceive; but he cannot take this quite strictly,
otherwise his opinion would be too paradoxical, since acquired
habits also and the contents of our memory are not always
apperceived, and do not even always come to our aid when
needed, although we often easily recall them to mind on some
trivial occasion which reminds us of them, in the same way
as we only need the beginning of a song to make us remember
the song. Moreover he limits his doctrine in other places by
saying that there is nothing in us which we have not at least
previously apperceived. But besides the fact that nobody
can guarantee by reason alone how far our past apperceptions
which may have been forgotten may have gone, especially in
view of the Platonic doctrine of reminiscence, which, mythical
though it is, is not incompatible, in part at least, with bare
reason: besides this, I say, why should it be necessary that
everything should be acquired by us by apperceptions of
external things, and nothing be able to be unearthed in

148 LEIBNIZ AND LOCKE

ourselves? Is our soul of itself alone so empty that apart
from images borrowed from without it is nothing? This is
not, I am convinced, an opinion that our judicious author
could approve. And where are there to be found tablets
which have not in themselves a certain amount of variety?
We shall never see a perfectly level and uniform surface.
Why, therefore, should we not also be able to provide some
sort of thought from deep within ourselves, when we are
willing to delve there? Thus I am led to believe that funda-
mentally his opinion on this point does not differ from mine,
or rather from the common opinion, inasmuch as he recognizes
two sources of our knowledge, the senses and reflection.

I am not sure that it will be so easy to reconcile him with
us and with the Cartesians when he maintains that the mind
does not always think, and in particular that it is without
perception during dreamless sleep; and when he protests
that since bodies can exist without motion, souls also might
well exist without thought. But here I answer somewhat
differently from what is usual; for I maintain that, naturally,
a substance cannot exist without activity, and that there
never even exists a body without motion. Experience is
already in my favour on this point, and to be persuaded of it
it is only necessary to consult the illustrious Mr. Boyle's
book l against absolute rest. But I believe that reason also
supports it, and this is one of the proofs which I use for
refuting the theory of atoms.

Besides, there are a thousand signs which make us think
that there are at all times an infinite number of perceptions
in us, though without apperception and without reflection;
that is to say changes in the soul itself which we do not
apperceive because their impressions are either too small and
too numerous, or too unified, so that they have nothing
sufficiently distinctive in themselves, though in combination

l Of Absolute Rest in Bodies. Robert Boyle (1627-1691) was a
famous chemist and physicist*

LEIBNIZ AND LOCKE 149

with others they do not fail to have their effect and to make
themselves felt, at least confusedly, in the mass. It is thus
that habituation causes us not to notice the motion of a mill
or waterfall, after we have lived near by for some time. It is
not that the motion does not continue to affect our organs,
and that something does not still take place in the soul to
correspond to it, on account of the harmony of the soul and
the body; it is that these impressions which are in the soul
and in the body, when they are devoid of the attractions of
novelty, are not strong enough to attract our attention and
memory, when these are attached to more absorbing objects.
For all attention demands some memory, and often when we
are not admonished, so to speak, and warned to pay attention
to certain of our present perceptions, we let them pass
without reflection and even without observing them; but
if someone draws attention to them immediately afterwards,
and makes us notice, for example, some sound that has just
been heard, we remember it, and we apperceive that we did
have some sensation of it at the time. Thus there were
perceptions which we did not immediately apperceive,
apperception in this case only arising through our attention
having been aroused after an interval, however small. In
order the better to form an opinion of these minute percep-
tions which we cannot distinguish in the crowd, I generally
make use of the example of the roar or noise which strikes us
when we are on the shore. To hear this noise as we do, we
must surely hear the parts of which the whole is made up,
that is to say the noises of each wave, although each of these
little noises only makes itself heard in the confused combina-
tion of all the others together, that is to say in the actual roar,
and would not be noticed if the wave which makes it were
the only one. For it is necessary that we should be slightly
affected by the motion of this wave, and that we should have
some perception of each of these noises, however small they
may be; otherwise we should not have the perception of a

ISO LEIBNIZ AND LOCKE

hundred thousand waves, since a hundred thousand nothings
cannot make a something. We never sleep so soundly but
that we have some feeble and confused feeling, and we should
never be awakened by the loudest noise in the world, if we
had not some perception of its beginning, small as it is; just
as we should never break a rope by the greatest exertion in
the world, if it were not to some small extent strained and
stretched by lesser efforts, although the slight extension they
produce is not apparent.

These minute perceptions are therefore more efficacious
in their consequences than we think. They it is that con-
stitute that indefinable something, those tastes, those images
of the qualities of the senses, clear in the mass but confused
in the parts, those impressions which surrounding bodies
make on us, which include the infinite, that link which
connects every being with all the rest of the universe. It
may even be said that as a result of these minute perceptions
the present is big with the future and laden with the past,
that everything is in league together (OV^TTVOIO. TTCLVTO, as
Hippocrates said), and that in the smallest substance eyes as
piercing as those of God could read the whole sequence of
things in the universe:

Quae sint, quaefuerint, quae moxfutura trahantur. 1
These insensible perceptions are also the signs and consti-
tuents of personal identity: the individual is characterized
by the traces or expressions of his previous states which
these perceptions preserve by connecting them with his
present state, and which can be known by a superior spirit,
even though the individual himself may not be conscious of
them, that is to say though he may no longer expressly
recollect them. But they (these perceptions, I mean) also
provide the means of rediscovering this recollection at need
through periodic developments which may one day occur.

1 ' The things that are, the things that have been, and those
that are presently to come.'

LEIBNIZ AND LOCKE 151

This is why, because of them, death can only be a sleep, and
cannot even go on being that, since, in animals, the per-
ceptions only cease to be sufficiently distinguished and become
reduced to a state of confusion which suspends apperception,
but which cannot last for ever not to speak here of man,
who must in this have great privileges in order to retain his
personality.

It is, moreover, these insensible perceptions which afford
the explanation of that wonderful pre-established harmony
of soul and body, and indeed of all monads or simple sub-
stances, which takes the place of the untenable theory of the
influence of the one on the other, and which in the opinion
of the author of the greatest of dictionaries 1 exalts the
grandeur of the Divine perfections beyond what has ever
been conceived. After this I should be adding but little if I
said that it is these minute perceptions which determine us in
many experiences without our giving them a thought, and
which deceive the common herd by giving the appearance of
an indifference of equilibrium, as if we were entirely indifferent
whether, for example, we turned to the right or to the left.
Nor is it necessary that I should point out here, as I have done
in the book itself, that they cause that uneasiness which, on
my showing, consists in something which differs from pain
only as the small from the great, and which yet often creates
our desire and even our pleasure, giving it a kind of savour.
It is moreover, these insensible parts of our sensible percep-
tions which bring it about that there is a relation between
those perceptions of colour, heat, and other sensible qualities
and the motions in the bodies which correspond to them;
whereas the Cartesians and our author, penetrating though
he is, conceive of the perceptions which we have of these
qualities as being arbitrary, that is to say, as if God had
given them to the soul at His good pleasure without any

1 i.e. Bayle. For the passage in Bayle's Dictionary referred
to here, see p. 126.

152 LEIBNIZ AND LOCKE

regard to any essential relation between perceptions and their
objects: an opinion which surprises me, and which seems to
me hardly worthy of the wisdom of the Author of things,
who does nothing without harmony and without reason.

In a word, the insensible perception is of as much use in
pneumatics * as is the insensible corpuscle in physics; and it
is equally unreasonable to reject the one or the other on the
pretext that it is beyond the reach of our senses. Nothing
takes place all at once, and it is one of my most important
and best verified maxims that nature makes no leaps. This
I called the law of continuity when I spoke of it in the first
News of the Republic of Letters; and the use of this law in
physics is very considerable : it means that the passage from
the small to the great and back again always takes place
through that which is intermediate, both in degrees and in
parts, and that a motion never arises immediately from rest,
nor is reduced to it except through a smaller motion, just as
we never manage to traverse any given line or length without
first traversing a shorter line although till now those who
have exhibited the laws of motion have not observed this
law, believing as they did that a body can receive in a moment
a motion contrary to its preceding one. All this brings us
to the conclusion that observable perceptions come by degrees
from those which are too small to be observed. To think
otherwise is to have but little knowledge of the immensely
subtle composition of things, which always and everywhere
include an actual infinity.

I have also noticed that, by virtue of insensible variations,
two individual things can never be perfectly alike, and that
they must always differ more than numero. This at once
puts out of court the blank tablets of the soul, a soul with-
out thought, a substance without action, the void in space,
atoms and even particles not actually divided in matter,
absolute rest, complete uniformity in one part of time, place,
1 An early name for the philosophy of mind or spirit.

LEIBNIZ AND LOCKE 153

or matter, the perfect globes of the second element which
are the offspring of the original perfect cubes, 1 and a thousand
other fictions of the philosophers fictions arising from their
incomplete notions, and not admitted by the nature of things,
but merely allowed to pass because of our ignorance and of the
slight attention we pay to the insensible; they can only be
made tolerable by being limited to abstractions made by the
mind, which protests that it is not denying any of the things
which it considers irrelevant to the present inquiry but only
setting them on one side. Otherwise, if we thought in good
earnest that the things we do not apperceive are not there in
the soul or in the body, we should fail in philosophy as in
politics, by neglecting TO pucpov, 2 insensible progressions;
whereas an abstraction is not an error, provided we know that
what we are ignoring is really there. This is the use made
of abstractions by mathematicians when they speak of the
perfect lines they ask us to consider, and of uniform motions
and other regular effects, although matter (that is to say the
mixture of the effects of the surrounding infinite) is always
making some exception. We proceed in this way so as to
distinguish the various considerations from one another, and
to reduce the effects to their reasons as far as is possible to us,
and to foresee some consequences; for the more careful we are
to neglect no consideration which we can regulate, the more
does practice correspond to theory. But it belongs to the
Supreme Reason, which misses nothing, distinctly to under-
stand the whole infinite, and to see all the reasons and all the
consequences. All that we can do in regard to infinities is to
know them confusedly, and at least to have distinct knowledge
that they exist. Otherwise we should have a very poor
recognition of the beauty and grandeur of the universe; we
should also be unable to have a sound physics to explain the
nature of bodies in general, and still less a sound pneumatics

1 The reference is to the vortex theory of Descartes.
1 lit. ' the small ' ; i.e. by neglecting very small items.

154 LEIBNIZ AND LOCKE

to include the knowledge of God, of souls, and of simple
substances in general.

This knowledge of insensible perceptions serves also to
explain why and how two souls, whether human or of some
other identical species, never come perfectly alike from the
Creator's hands, but each has always from the beginning its
own relation to the point of view it will have in the universe.
But this follows from what I pointed out previously about
two individuals, namely that their difference is always more
than a numerical one. There is also another important point
on which I am obliged to differ not only from the opinions
of our author, but also from those of the greater part of the
moderns; that is, that like most of the ancients I hold that all
superhuman beings, all souls, all simple created substances,
are always joined to a body, and that there never are entirely
separate souls. I have a priori reasons for this, but there
will be found to be this advantage also in my doctrine that it
solves all the philosophical difficulties about the state of souls,
their perpetual conservation, their immortality, and their
operation: the difference between one state of the soul and
another is never and has never been anything other than that
between the more and the less sensible, the more and the less
perfect, or the other way round, and so the past or future
state of the soul is as explicable as its present state. The
smallest reflection suffices to show that this is reasonable,
and that a leap from one state to another infinitely different
state could not be natural. I am surprised that the schools
should have causelessly given up natural explanations, and
should have been ready deliberately to plunge into very great
difficulties and thus to provide occasion for the apparent
triumphs of free-thinkers; all of whose reasons collapse at
once on this explanation of things, in which there is no more
difficulty in conceiving the conservation of souls (or rather
on my view of the whole animal) than there is in the change
from the caterpillar into the butterfly, and in the conserva-

LEIBNIZ AND LOCKE 155

tion of thought during sleep sleep to which Jesus Christ
with divine propriety likened death. I have already said
that no sleep can last for ever, and it will have least duration,
or almost none at all, in the case of rational souls, which are
always destined to retain the personality which has been
given to them in the City of God, and which consequently
have memory, so that they may be more susceptible of
punishments and rewards. I add further that in general no
derangement of its visible organs is capable of carrying
things to the point of complete confusion in the animal or of
destroying all its organs, and of depriving the soul of the
whole of its organic body and of the ineffaceable remains of
all its preceding traces. But the ease with which the ancient
doctrine that angels have subtle bodies * has been abandoned
(a doctrine that has been confounded with the corporeality
of the angels themselves), the introduction of supposed
intelligences without bodies among created things (a view
that has been much strengthened by Aristotle's doctrine
that such intelligences make the heavens revolve), and
finally the mistaken opinion that has existed that the con-
servation of the souls of the brutes cannot be maintained
without falling into metempsychosis and transferring them
from body to body, and the perplexity some have felt through
not knowing what to do with them all these things have,
in my opinion, led to the neglect of the natural way of
explaining the conservation of the soul. This has done much
injury to natural religion, and has caused some people to
believe that our immortality was but a miraculous grace of
God. Our illustrious author also speaks of it with some
doubt, as I shall subsequently point out. But it would be
well if all those who are of this opinion had spoken of it as
wisely and sincerely as he ; for it is to be feared that some who

1 i.e. made of some more rarefied stuff than ordinary matter.
Locke uses the word in this connection (to represent the Latin
subtilis) in the correspondence with the Bishop of Worcester.

156 LEIBNIZ AND LOCKE

speak of immortality through grace merely do so to preserve
appearances, and at bottom are not very far from those
Averroists and certain pernicious Quietists, who picture an
absorption and reunion of the soul with the ocean of Divinity,
a notion whose impossibility is perhaps shown up by my
system alone.

It appears, moreover, that we differ also in regard to
matter, in that the author thinks that the existence of a
void is necessary to motion, because he believes that the
small parts of matter are rigid. 1 I admit that if matter were
composed of such parts, motion in a plenum would be im-
possible, just as if a room were filled with quantities of small
pebbles without there being in it the least empty space. But
I do not admit this supposition, for which, moreover, there
does not appear to be any reason, although our gifted author
goes so far as to hold that rigidity 1 or cohesion of parts
is the essence of matter. Space should rather be conceived
of as full of a matter originally fluid, susceptible of any
division, and submitted indeed actually to divisions and
subdivisions ad infinitum; with this difference, however, that
it is divisible and divided unequally in different places on
account of motions which are already helping to a greater
or less degree to produce the divisions. This means that it
has throughout a degree of rigidity as well as of fluidity, and
that there does not exist any body which is absolutely hard
or absolutely fluid; that is to say that it is impossible to find
in any body any atom whose hardness is indefeasible, or any
mass which is entirely indifferent to division. Besides, the
order of nature, and particularly the law of continuity, make
both equally impossible.

1 Locke's own term is solid, and solidity. He says : That which
hinders the approach of two bodies, when they are moved one
towards another, I call solidity . . . but if any one think it better to
call it impenetrability , he has my consent [Essay, Bk. II, ch. iv, i],
But I do not think that Leibniz's word here (roide) can properly
be translated by solid. The word hard is rejected by Locke on the
ground that a hard body is no more solid than a soft one.

LEIBNIZ AND LOCKE 157

I have also shown that cohesion, which could not of itself
be the result of impulse or of motion, would cause a traction,
strictly speaking. For if there were a body originally
rigid, an Epicurean atom, for example, which contained a
part projecting from it in the form of a hook (since we may
imagine atoms of all kinds of shapes), this hook when impelled
would draw with it the rest of the atom, that is to say the
part which was not being impelled, and which did not fall
in the line of impulse. Our gifted author, however, is
himself opposed to these philosophic tractions, such as were
formerly attributed to nature's abhorrence of a vacuum, and
reduces them to impulses, maintaining in agreement with
the moderns that one part of matter can only operate im-
mediately on another by impelling it by contact; wherein I
think they are right, because otherwise the operation is in
no way intelligible.

I must not, however, conceal the fact that I have observed
a kind of recantation on this point on the part of our excellent
author, whose modesty and sincerity in this I cannot too
highly praise, just as on other occasions I have admired his
penetrating insight. It is in the reply to the second letter
of the late Bishop of Worcester, printed in 1699, page 408,
where, in order to justify the view he had upheld against
this learned prelate, namely that matter was capable of
thought, he says among other things: 'It is true, 1 say
"that bodies operate by impulse, and nothing else" (Essay,
Bk. II, ch. viii, n). And so I thought when I writ it, and
can yet conceive no other way of their operation. But I am
since convinced by the judicious Mr. Newton's incomparable
book, that it is too bold a presumption to limit God's power, in
this point, by my narrow conceptions. The gravitation of
matter towards matter, by ways inconceivable to me, is not only
a demonstration that God can, if he pleases, put into bodies
powers and ways of operation, above what can be derived from
our idea of body or can be explained by what we know of matter,

158 LEIBNIZ AND LOCKE

but also an unquestionable and everywhere visible instance,
that he has done so. And therefore in the next edition of my
book 1 shall take care to have that passage rectified. 11 I find
that in the French translation of this book, which was no doubt
taken from the latest editions, this n reads thus: 'It is
evident, at least as far as we can conceive it? that bodies act
upon one another by impulse and not otherwise; for it is
impossible for us to understand that a body can act upon that
which it does not touch, which is as much as to imagine that
it can act where it is not.' 3

I cannot but praise this modest piety on the part of our
famous author, who recognizes that God can do things beyond
what we can understand, and thus that there may be in-
conceivable mysteries in the articles of faith: but I should
not wish us to be obliged to have recourse to miracles in the
ordinary course of nature, and to allow the existence of
powers and operations which are absolutely inexplicable.
Otherwise we should be granting too much licence to bad
philosophers on the strength of what God can do. If we
admit these centripetal faculties or immediate attractions from
a distance without its being possible to make them in-
telligible, I see nothing to prevent our Scholastics from
saying that everything is done simply through their 'faculties'
and from upholding their 'intentional species', which go
from objects up to us, and find a way even of entering our
souls. If this is true:

Omnia jam fient, fieri quae posse negabam.*
So that it seems to me that our author, judicious though he

1 Italics indicate Locke's own exact words.

* These italics are Leibniz's.

1 In the English edition 1 1 runs as follows : The next thing to be
considered is, how bodies produce ideas in us; and that is manifestly
by impulse, the only way which we can conceive bodies to operate in.

4 'Everything will now happen which I declared to be im-
possible.'

LEIBNIZ AND LOCKE 159

is, is in this going rather too much from one extreme to the
other. He makes difficulties about the operations of souls,
when it is only a question of admitting what is not sensible,
and here we have him granting to bodies what is not even
intelligible, in allowing them powers and activities beyond
everything which, in my opinion, a created mind can do and
understand, since he grants them attraction, even at great
distance and without limiting himself to any stated sphere
of activity, and that in order to uphold a view which seems
no less inexplicable, to wit, the possibility of thinking in
matter in the natural order.

The question he is discussing with the celebrated prelate,
who had attacked him, is whether matter can think, and as
this is an important point, even for the present work, I
cannot avoid going into the subject a little and taking some
account of their dispute. I will set forth the substance of
it as regards this subject, and will take the liberty of saying
what I think about it. The late Bishop of Worcester, being
apprehensive, though in my opinion without great cause, that
our author's doctrine of ideas was liable to some abuses pre-
judicial to the Christian faith, undertook to examine certain
parts of it in his vindication of the doctrine of the Trinity.
He first gives this excellent author his due by recognizing
that he holds the existence of the mind as certain as that of
the body, although one of these substances is as little known as
the other; he then asks (page 241 seq.) how reflection could
possibly assure us of the existence of mind, if God can give
matter the faculty of thinking (as our author believes, Bk. V,
ch. iii), since in this case the way of ideas, which is required
to discriminate between the properties of soul and of body,
would become useless; whereas it was said in Book II of the
Essay on the Human Understanding (ch. xxiii, 15, 27, 28),
that the operations of the soul provide us with the idea of
mind, and the understanding together with the will makes
this idea as intelligible to us as the nature of body is made
N9S

160 LEIBNIZ AND LOCKE

intelligible to us by solidity and impulse. This is how our
author replies in his first letter (page 65 seq.): '/ think it may
be proved from my principles, and 1 think I have done it, that
there is a spiritual substance in us . . . We experiment in ourselves
thinking. The idea of this action, or mode of thinking, is in-
consistent with the idea of self -subsistence, and therefore has a
necessary connection with a support or subject of inhesion : the
idea of that support is what we call substance . . . for the general
idea of substance being the same everywhere, the modification of
thinking, or the power of thinking, joined to it, makes it a spirit,
without considering what other modifications it has, as whether
it has the modification of solidity or not. As, on the other side,
substance thzt has the modification of solidity, is matter, whether
it has the modification of thinking or not. And therefore if your
lordship means by a spiritual an immaterial substance, I grant
I have not proved, nor upon my principles can it be proved,
(your lordship meaning, as I think you do, demonstratively
proved) that there is an immaterial substance in us that thinks.
Though I presume, what I have said about the supposition of
a system of matter thinking (Bk. IV, ch. x, 16) (which there
demonstrates that God is immaterial) will prove it in the highest
degree probable, that the thinking substance in us is immaterial.
. . . Yet, / have shown [adds the author, page 68] that all the
great ends of religion and morality are secured barely by the im-
mortality of the soul, without a necessary supposition that the
soul is immaterial.

In his reply to this letter the learned bishop, to show that
our author was of another opinion when he wrote the second
book of his Essay, cites from it on page 51 this passage (taken
from the same book, chapter xxiii, 15), where it is said that
by the simple ideas we have taken from our own minds we are
able to frame the complex idea of an immaterial spirit. And
thus by putting together the ideas of thinking, perceiving, liberty,
and power of moving themselves, and other things, we have as
clear a perception and notion of immaterial substances as we

LEIBNIZ AND LOCKE 161

have of material. He further cites other passages to show
that the author opposed mind to body. He says (page 54)
that the ends of religion and morality are best secured by
proving that the soul is immortal by its very nature, that is to
say immaterial. He further adduces (page 60) this passage,
that all our ideas of the several sorts of substances are nothing but
collections of simple ideas ; and that thus our author believed
that the idea of thinking and willing gave a different substance
from that given by the idea of solidity and impulse; and ( 17)
regards these ideas as constituting body as opposed to mind.

The Bishop of Worcester might have added that from the
fact that the general idea of substance is in body and in mind,
it does not follow that their differences are modifications of
one and the same thing, as our author has just said in the
passage I quoted from his first letter. It is necessary to
distinguish properly between modifications and attributes.
The faculties of having perception and of acting, extension,
and solidity, are attributes of perpetual and principal predi-
cates; but thinking, impetus, shapes, and motions are modifi-
cations of these attributes. Further, we ought to distinguish
between physical (or rather real) genus, and logical or ideal
genus. Things which are of the same physical kind or which
are homogeneous, are of the same matter so to speak, and can
often be changed one into another by changing their modifi-
cations, like circles and squares. But two heterogeneous
things may have a common logical genus, and then their
differences are not simple accidental modifications of one
self-same subject or of one self-same metaphysical or physical
matter. Thus time and space are quite heterogeneous things,
and we should be wrong to imagine some kind of common real
subject which had only continuous quantity in general and
whose modifications resulted in time or space. People may
laugh at these philosophical distinctions between two genera,
the one only logical, the other real, and between two matters,
one physical that of bodies the other only metaphysical

162 LEIBNIZ AND LOCKE

or general, as if someone said that two parts of space are of
the same matter or that two hours are also of the same matter
as one another. Yet these distinctions are not a mere
matter of terms, but are in the things themselves; and they
seem to be particularly relevant here, where their confusion
has given rise to a false conclusion. These two genera have
a common notion, and the notion of real genus is common to
both matters, so that their genealogy would be as follows:

Logical merely, the
variations consisting
of simple differences.

* Real, whose differ- ( Metaphysical merely , in which

ences are modifica- 1 there is homogeneity,

tions, that is to say 1 Physical, in which there is a

matter. I solid homogeneous mass.

I have not seen our author's second letter to the bishop,
and the answer the latter makes to it hardly touches the point
about the thinking of matter. But our author's reply to this
second answer comes back to it. 'God (he says, nearly in
these words, page 397), superadds to the essence of matter
what qualities He pleases; to some parts simple motion, to
plants vegetation, and to animals sense. Those who agree
with me so far exclaim against me when I go a step further
and say, God may give to matter thought, reason, and volition,
as if that would destroy the essence of matter. To make good
this assertion they say that thought and reason are not in-
cluded in the essence of matter: which proves nothing, for
motion and life are just as little included in it. They also
urge that we cannot conceive how matter can think : but our
conception is not the measure of God's omnipotency.' After
this he quotes the example of the attraction of matter, page
399 and particularly page 408, where he speaks of the gravita-
tion of matter towards matter, attributed to Mr. Newton (in
the words I have quoted above), admitting that we cannot

LEIBNIZ AND LOCKE 163

conceive how the attraction takes place. This, in effect, is
going back to qualities which are occult, or, what is more, in-
explicable. He adds (page 401) that nothing is more likely to
assist the sceptics than to deny what we do not understand,
and (page 402) that we cannot conceive even how the soul
thinks. He wants to maintain (page 403) that, since both
substances, material and immaterial, can be conceived in their
bare essence without any activity, it rests with God to give to
the one or to the other the power of thinking. And he wants
to take advantage of the admission of his opponent, who had
granted sense in brutes, but would not grant them any
immaterial substance. He claims that liberty and self-
consciousness (page 408) and the power of making abstrac-
tions (page 409) can be given to matter, not as matter, but as
enriched by a divine power. Finally he reports (page 434) the
observation of a traveller as important and judicious as M. de
La Loubre that the pagans of the East know of the immor-
tality of the soul without being able to understand its
immateriality.

With regard to all this I may say, before coming to the
explanation of my opinion, that it is certain that matter is
as little capable of mechanically producing sensation as of
producing reason, as our author agrees; that I fully recognize
that it is not allowable to deny what we do not understand,
but I add that we have the right to deny (in the order
of nature at least) what is absolutely unintelligible and
inexplicable. I maintain also that substances, whether
material or immaterial, cannot be conceived in their bare
essence without any activity, activity being of the essence
of substance in general; and finally that the conception of
created beings is not the measure of God's power, but that
their conceptivity, or power of conceiving, is the measure
of the power of nature; for everything which conforms with
the order of nature can be conceived or understood by some
created being.

164 LEIBNIZ AND LOCKE

Those who understand my system will see that I cannot
agree altogether with either of these excellent authors; their
dispute, however, is very instructive. Let me explain myself
distinctly: it must above all things be considered that the
modifications which can attach to a subject naturally or
without miracle, must come to it from the limitations or
variations of a real genus, or of an original nature which
is constant and absolute. This is how we distinguish in
philosophy the modes of an absolute being from that being
itself; for instance we know that size, shape, and motion are
manifestly limitations and variations of corporeal nature.
For it is clear how a limitation of extension gives figures,
and that the change which therein takes place is nothing but
motion. And every time we find some quality in a subject,
we ought to think that if we understood the nature of this
subject and of this quality, we should conceive how this
quality could result from it. Thus, in the order of nature
(miracles apart) God does not arbitrarily give to substances
such and such qualities indifferently, and He never gives them
any but those which are natural to them, that is to say
qualities which can be derived from their nature as explicable
modifications. Thus we see that matter does not naturally
have the attraction mentioned above, and does not of itself
go in a curve, because it is not possible to conceive how
this takes place, that is to say, to explain it mechanically,
whereas what is natural ought to be able to be rendered
distinctly conceivable, if we were admitted into the secrets of
things. This distinction between what is natural and ex-
plicable and what is inexplicable and miraculous removes
all the difficulties: in rejecting it we should be upholding
something worse than occult qualities, and in so doing we
should be renouncing philosophy and reason, and throwing
open sanctuaries for ignorance and idleness, by a stupid
system which admits not only that there are qualities which
we do not understand (of which there are only too many),

LEIBNIZ AND LOCKE 165

but also that there are some which the greatest mind, even
if God provided him with every possible advantage, could
not understand that is to say they would be either miracu-
lous or without rhyme or reason. It would indeed be with-
out rhyme or reason that God should perform miracles in the
ordinary course; so that this do-nothing hypothesis would
destroy equally our philosophy which searches for reasons,
and the Divine reason which provides them.

We can now turn to the question of thinking. It is certain
that our author recognizes in more than one place that
thinking cannot be an intelligible modification of matter, or
one which could be understood and explained ; that is to say,
a sentient or thinking being is not a mechanical thing like a
watch or a windmill, so that we could conceive of sizes,
shapes, and motions in such a mechanical conjunction that
they could produce in a mass, in which there was nothing of
the kind, something capable of thought and even of sensa-
tion, which thinking and sensing would likewise stop if the
mechanism got out of order. Thus it is not natural to matter
to have sensation and to think, and there are only two ways
in which it could do so; one of which is for God to join to
it a substance to which thought is natural, and the other for
God to endow it with thought miraculously. In this, then,
I am entirely of the opinion of the Cartesians, except that I
extend it to brutes also, and hold that they have sensation,
and souls which are, properly speaking, immaterial, and as
incapable of perishing as the atoms of Democritus or Gassendi;
whereas the Cartesians, being needlessly embarrassed about
the souls of brutes, and not knowing what to do with them
if they were preserved (since it did not occur to them that the
animal might be preserved in a minute form), were compelled
to deny them even sensation, contrary to all appearances,
and to the judgment of mankind. But if it is argued that
God, at least, could add the faculty of thinking to such a
mechanism, I would answer that if this occurred, and if

166 LEIBNIZ AND LOCKE

God added this faculty to matter without at the same time
endowing it with a substance of such a kind that this same
faculty (as I conceive it) could be inherent in it, that is to say
without adding an immaterial soul, then matter would have
to be exalted miraculously so as to be able to receive a power
of which it is not capable naturally: just as some Scholastics
claim that God exalts fire to the point of giving it the power
directly to burn spirits separated from matter which would
be a miracle pure and simple. It is enough that we cannot
maintain that matter thinks unless we attribute to it an
imperishable soul, or rather a miracle, and that thus the
immortality of our souls follows from what is natural: since
we could not maintain that they are extinguished except by
a miracle, whether by exalting matter, or by annihilating the
soul. For we know, of course, that the power of God could
render our souls mortal, even though they may be immaterial
or immortal by nature, since He can annihilate them.

Now this truth of the immateriality of the soul is un-
doubtedly of consequence. For it is of infinitely more use
in religion and morals, especially in our day (when many
people have scant respect for revelation by itself or for
miracles), to show that souls are naturally immortal, and that
it would be a miracle if they were not, than to maintain that
our souls must naturally die, and that it is by virtue of a
miraculous grace, based solely on the promise of God, that
they do not die. We have, moreover, known for a long time
that those who wished to destroy natural religion, and
reduce everything to revealed religion, as if reason taught us
nothing about it, have been held suspect, and not always
without reason. But our author is not of their number. He
upholds the proof of the existence of God and attributes to
the immateriality of the soul a probability of the highest
degree, which may consequently pass for a moral certainty,
so that I imagine that having as much sincerity as penetra-
tion, he might quite well come to agree with the doctrine I

LEIBNIZ AND LOCKE 167

have just expounded. This doctrine is fundamental in every
reasonable philosophy, for otherwise I do not see how we can
prevent ourselves from falling back into fanatical philosophy,
such as the Mosaic philosophy of Fludd, which accounts for
all phenomena by attributing them immediately and miracu-
lously to God, or into a barbarous philosophy like that of
certain philosophers and physicians of bygone days, who
still savoured of the barbarism of their age, and who to-day
are justly despised; these accounted for appearances by
expressly fabricating suitable occult qualities or faculties,
which were supposed to be like little demons or sprites able
to do what was required of them out of hand just as if there
were watches able to tell the time by some 'horodeictic
faculty* without the need of wheels, or mills able to crush
grain by a tractive faculty* without the need of anything
in the nature of millstones. As to the difficulty many people
find in conceiving an immaterial substance, that soon ceases
to be felt (in part at least) when there is no longer any
question of substances separated from matter; such sub-
stances do not, I hold, ever naturally exist among created
things.

BOOK I. OF INNATE NOTIONS

CHAPTER I

Whether there are any Innate Principles in the Human Min d

2i. a PniLALETHES. 2 If the mind assents so promptly to
certain truths, may this not come from the consideration
of the nature of things, which does not suffer it to think

1 The number of the section refers to the section in the corres-
ponding chapter and book of Locke's Essay; i.e. in this case
to Essay, Bk. I, ch. i, 21. It will be seen that Leibniz does not
always follow the order of Locke's sections, but sometimes takes
the points in an order that suits his own argument. A large part
of the present chapter is omitted here.

8 Cf. p. 142, note.

168 LEIBNIZ AND LOCKE

otherwise, rather than because these propositions have been
printed naturally in the mind ?

THEOPIIILUS. Both these doctrines are true. The nature
of things and the nature of the mind here agree. And since
you oppose the consideration of the thing to the apperception
of what is printed in the mind, your objection shows, sir,
that those whose doctrines you are upholding understand
by innate truths, only such as would be approved naturally,
as if by instinct, and without apprehending them except
confusedly. There are some of this nature, and I shall
have occasion to speak of them. But what is called the
natural light presupposes a distinct knowledge, and often
enough the consideration of the nature of things is nothing
else than the knowledge of the nature of our mind and of
these innate ideas, for which there is no need to search outside.
Thus I call innate those truths which have no need of such
consideration for their verification . . .

23. PH. . . . But what do you say, sir, to this challenge
of one of my friends ? I would gladly have any one name, 1 he
says, that proposition whose terms or ideas were either of
them innate.

TH. I should name the propositions of arithmetic and
geometry, which are all of that nature; and as regards
necessary truths, it is not possible to find any others.

25. PH. Many people will find that very strange. Can
it be said that the most difficult and profoundest sciences
are innate ?

TH. Actual knowledge of them is not innate, but rather
what may be called virtual knowledge; just as the figure
traced by the veins of the marble is in the marble, before
they are uncovered by the workman.

PH. But is it possible that children, when they receive
notions which come to them from outside, and give to them

1 In the speeches of Philalethes italics indicate Locke's own
exact words ; in those of Theophilus the italics are Leibniz's.

LEIBNIZ AND LOCKE 169

their assent, should still have no knowledge of those which
are supposed to be innate and to form part of their mind, on
which, it is said, they are imprinted in indelible characters to
serve as a foundation? This would be to make nature take
pains to no purpose; or at least, to write very ill, since its
characters could not be read by those eyes which saw other things
very well.

TH. The apperception of what is in us depends upon the
presence of attention and upon order. Now it is not only
possible, it is also fitting, that children should pay more
attention to the notions of sense, because attention is
regulated by need. The event, however, makes it clear in
the sequel that nature did not take pains to no purpose in
printing in us innate knowledge, since without such know-
ledge there would be no means of arriving at actual know-
ledge of necessary truths in the demonstrative sciences, and
at the reasons of facts; and so we should have nothing more
than the brutes.

5. PH. . . . But you will have rather more difficulty in
answering what I am now going to propound to you, namely
that if any one particular proposition can be said to be
innate, then the same reasoning will enable it to be main-
tained that all propositions that are reasonable, and that
the mind is ever capable of regarding as such, are already
imprinted in the soul. . . . Even supposing that there are
truths which can be imprinted in the understanding, without
the understanding perceiving them, I do not see how in
respect of their original they can differ from the truths which
it is simply capable of knowing.

TH. The mind is not simply capable of knowing them, but
also of finding them in itself. If it had only the simple
capacity to receive knowledge, or the passive potency
necessary for that, as much without determinations as that
which the wax has to receive shapes and the tabula rasa to

170 LEIBNIZ AND LOCKE

receive letters, then it would not be the source of necessary
truths, as I have just proved that in fact it is. For it is in-
contestable that the senses are not sufficient to make us see
their necessity, and so the mind has the dispositions (as
much active as passive) to draw them itself out of its own
depths; though the senses are necessary to give to it the
occasion and the attention required for this, and to lead it
rather to the one sort than to the other. Thus you see, sir,
that these people, clever as they are in other respects, who
are of a different opinion, seem not to have reflected
sufficiently about the consequences of the difference between
truths which arc necessary or eternal and truths of experience,
as I have already remarked and as our whole dispute makes
clear. The original proof of necessary truths comes from the
understanding alone, and all other truths come from ex-
periences or from observations of the senses. Our mind is
capable of knowing both the one sort and the other, but
it is the source of the first; whatever number of particular
experiences we may have of a universal truth, we cannot
assure ourselves of it for always by induction, without
apprehending its necessity by reason.

PH. But is it not true that if these words, to be in the
understanding) have any positive meaning they mean to be
perceived and apprehended by the understanding?

TH. To me they mean something quite different. It is
sufficient if that which is in the understanding is capable of
being found there, and if the original sources of proofs of the
truths which are here in question are simply in the under-
standing: the senses may suggest, justify, and confirm these
truths, but they cannot demonstrate their infallible and
perpetual certainty.

18. TH. . . . Thoughts are actions, and apprehensions or
truths, in so far as they are in us, even though we are
not thinking of them, are habits or dispositions; and we

LEIBNIZ AND LOCKE 171

have clear knowledge of things of which we hardly think
at all.

PH. It is very difficult to conceive how a truth can be in
the mind, if the mind has never thought of that truth.

Tn. To say that is like saying that it is difficult to con-
ceive that there are veins in the marble before they are
uncovered. It appears, too, that this objection comes very
near to a petitio principii. All those who allow innate truths,
without making them dependent on a Platonic reminiscence,
allow some of which the mind has not yet thought. Besides,
this reasoning proves too much. If truths are thoughts, it
will deprive us, not only of truths of which we have never
thought, but also of those of which we have thought but are
not actually thinking now. If truths are not thoughts, but
habits and aptitudes, natural or acquired, then there is
nothing to prevent the existence in us of truths of which we
have never thought, no, nor ever shall think.

BOOK II. OF IDEAS

CHAPTER I

In which the author treats of ideas in general, and examines by
the way whether the soul of man thinks always

i. PH. Having now examined whether ideas are innate,
let us consider their nature and their differences. Is it not
true that an idea is the object of thinking?

TH. I agree, provided that you add that it is an immediate
internal object, and that this object is an expression of the
nature or of the qualities of things. If an idea were the form
of thinking, it would come into being and cease with the
actual thoughts which correspond to it; but being the object
of thought, it can exist anterior to and posterior to the

172 LEIBNIZ AND LOCKE

thoughts. External sensible objects are only mediate,
because they cannot act immediately on the soul. God
alone is the immediate external object. It might be said that
the soul itself is its own immediate internal object; but it is
so only as containing ideas, or that which corresponds to
things. For the soul is a little world, in which distinct ideas
are a representation of God and confused ideas are a represen-
tation of the universe.

2. PH. Our friends, who supposed that at the beginning
the soul is a blank tablet, void of all characters and without
any ideas, ask themselves how it comes to receive ideas, and
by what means it acquires such a vast store. To this they
answer in one word: from experience.

TH. This tabula rasa of which they talk so much, is nothing
in my opinion but a fiction which nature does not admit,
and which is founded only in the incomplete notions of the
philosophers, like the void, atoms, rest (whether absolute
rest or the relative rest of two parts of a whole in relation
to one another), or like primary matter conceived as quite
formless. Things which are uniform and contain no variety
are never anything but abstractions, like time, space, and
the other entities of pure mathematics. There is no body
whose parts are at rest, and there is no substance which has
not something to distinguish it from every other substance.
Human souls differ not only from other souls, but also
among themselves, although the difference is not of the
nature of those which are called specific. And in accordance
with the proofs which I think I can supply, every substantial
thing, be it soul or body, has its relation to every other
substantial thing, which is peculiar to itself; and one must
always differ from another by intrinsic denominations. It
need hardly be said that those who talk so much of this
tabula rasa, after emptying it of all ideas, could not say
what remains, just as the Schoolmen have nothing left for
their primary matter. I shall be told, perhaps, that this

LEIBNIZ AND LOCKE 173

tabula rasa of the philosophers means that the soul has
naturally and originally nothing but bare faculties. But
faculties without any activity, in a word the pure potencies
of the Schools, these too are nothing but fictions, of which
nature knows nothing, and which are obtained by making
abstractions. For where in the world will you find a faculty
which shuts itself up in a mere potency and never exercises
any activity? There is always a particular disposition to
action, and to one action rather than another. And besides
the disposition there is always a tendency to action; indeed
there is always an infinite number of them in every subject
at any given time; and these tendencies are never without
some effect. Experience is necessary, I allow, for the soul
to be determined to such and such particular thoughts, and
for it to take notice of the ideas which are in us. But by
what means can experience and the senses provide ideas?
Has the soul windows ? Does it resemble a tablet? Is it like
wax? It is evident that all those who speak thus of the
soul treat it at bottom as corporeal. I shall have brought
against me the axiom, accepted among the philosophers,
that there is nothing in the soul save that which comes from the
senses. But we must except the soul itself and its affections.
Nihil est in intellectu, quod non fuertt in sensu ; excipe,
nisi ipse intellectus* Now the soul contains existence,
substance, unity, identity, cause, perception, reasoning, and
a quantity of other notions which the senses could not afford.
This is in agreement with your friend the author of the
Essay, who finds the source of a good part of our ideas in the
reflection of the mind upon its own nature.

PH. I hope, then, that you will agree with this able author
that all our ideas come from sensation or from reflection,
that is to say, from the observations we make either of

1 ' There is nothing in the intellect which was not previously in
the senses; provided we make the reservation, except the intellect
itself/

174 LEIBNIZ AND LOCKE

external, sensible objects or of the internal operations of
our soul.

TH. To avoid a dispute over which we have delayed too
long, I must make it quite clear at the outset, sir, that when
you say that ideas come to us from the one or the other of
these causes I understand you to speak of the actual per-
ception of them, for I think I have shown that they are in us
before they are apperceived in so far as they contain anything
distinct. 1

CHAPTER IX

Of Perception

i. PH. Let us now turn to the ideas of reflection in detail.
Perception , as it is the first faculty of the mind exercised about
our ideas, so it is the first and simplest idea we have from
reflection. Thinking signifies that sort of operation of the
mind about our ideas, wherein the mind is active ; where it, with
some degree of voluntary attention, considers anything. For in
bare naked perception, the mind is, for the most part, only
passive ; and what it perceives, it cannot avoid perceiving.

TH. We might perhaps add that brutes have perception,
and that it is not necessary that they should have thought, that
is to say, should have reflection or anything that can be the
object of reflection. Moreover, we ourselves have minute
perceptions which we do not apperceive in our present state.
It is true that we could quite well apperceive them or reflect
on them, if we were not deterred by their multitude, which
distracts our mind, and if they were not effaced or rather
obscured by greater ones.

4. PH. I admit that whilst the mind is intently employed
in the contemplation of some objects it takes no notice of im-

1 In the remainder of this chapter Leibniz discusses Locke's
contention that the mind thinks not always.

LEIBNIZ AND LOCKE 175

pressions of sounding bodies made upon the organ of hearing.
A sufficient impulse there may be on the organ ; but if not reaching
the observation of the mind, there follows no perception.

TH. I should prefer to distinguish between perception and
apperceiving. The perception of the light or of the colour, for
example, which we do apperceive, is composed of a number of
minute perceptions, which we do not apperceive; and a noise
of which we have perception, but of which we do not take
notice, becomes apperceptible by a slight addition or increase.
For if what precedes made no impression on the soul,
neither would this little addition make any, and the whole
would make none either. I have already touched on this
point in ch. i of this book, u, 12, and 15.

8. PH. We are further to consider concerning perception,
that the ideas we receive by sensation are often in grown people
altered by the judgment, without our taking notice of it. The
idea imprinted on the mind by a globe of uniform colour is
that of aflat circle variously shadowed and with several degrees
of light and brightness coming to our eyes. But we have by use
been accustomed to perceive what kind of appearance convex
bodies are wont to make in us, what alterations are made in the
reflections of light by the dijference of the sensible figures of
bodies ; and so we put in the place of what appears to us the
actual cause of the image, and confuse judgment with vision.

TH. Nothing is more true, and this it is which provides
the painter with the means of deceiving us by the artifice of
a perspective which we can well understand. When bodies
have flat surfaces, we can represent them without making
use of shadows, by employing outlines only, and by simply
making pictures in the fashion of the Chinese, only more
in proportion than theirs. This is the usual way of drawing
medals, so that the draughtsman may keep closer to the
precise features of the originals. But there is no way by
drawing, of exactly distinguishing the inside of a circle
from the inside of a spherical surface bounded by that circle,
095

176 LEIBNIZ AND LOCKE

without the assistance of shadows, since the insides have in
neither case any distinct points or distinguishing features,
although there is all the same a great difference which must be
shown. This is why M. Des Argues laid down precepts about
the effect of tints and shadows. When a painting deceives us
there is a double error in our judgments; for in the first place
we substitute the cause for the effect, and think we are seeing
immediately that which is the cause of the image, rather like
a dog who barks at a mirror. For, strictly speaking, we only
see the image, and are affected by nothing but rays of light.
And since these rays of light need time (however short), it is
possible that the object might have been destroyed during
this interval and no longer exist by the time the ray reaches
the eye; and what no longer exists cannot be the present
object of vision. In the second place we are mistaken in
substituting one cause for another, and thinking that what
only comes from a flat painting is derived from a body; so
that in this case there is in our judgments at the same time
both a metonymy and a metaphor; for the very figures of
rhetoric become sophisms when they impose upon us. This
confusion of the effect with the cause, whether real or alleged,
often enters into our judgments in other places as well. It
is involved when we feel our bodies, or what touches them,
and when we move our arms, by an immediate physical
influence, which we think constitutes the communion of the
soul and the body; whereas the truth is that we feel and
change in this way only what is within us.

8. PH. I shall here insert a problem which was sent to
the illustrious Mr. Locke by that very ingenious and studious
promoter of real knowledge, the learned Mr. Molyneux. It
was stated very much as follows : Suppose a man born blind,
and now adult, and taught by his touch to distinguish between
a cube and a sphere of the same metal, and nighly of the same
bigness, so as to tell, when he felt one and the other, which is the
cube, which the sphere. Suppose, then, the cube and sphere

LEIBNIZ AND LOCKE 177

placed on a table, and the blind man be made to see: quaere,
whether by his sight, before he touched them, he could now dis-
tinguish and tell which is the globe, which the cube ? I beg you,
sir, to tell me your opinion on this matter.

TH. I should need time to think about this question,
which seems to me a remarkable one; but since you urge me
to reply on the spot, I venture to say, between ourselves,
that I believe that if the blind man knew that the two
figures lie was looking at were the cube and the globe, he would
be able to distinguish them, and say without touching them:
This is the globe, this the cube.

PH. 1 fear that you must be numbered with the crowd of
those who have wrongly answered Mr. Molyncux. For in the
letter which contained this question, he stated that he had
propounded it to various men of acute mind, apropos of Mr.
Locke's Essay on the Human Understanding, and had found
hardly one who began by giving him what he considered
the right answer, although they became convinced of their
mistake on hearing his reasons. This acute and judicious
author answers: Not. For, though he (the blind man) has
obtained the experience of how a globe, how a cube affects his
touch, yet he has not obtained the experience, that what affects
his touch so or so must affect his sight so or so ; or that a pro-
tuberant angle in the cube, that pressed his hand unequally,
shall appear to his eye as it does in the cube. The author of
the Essay declares that he is altogether of the same opinion.

TH. Perhaps Mr. Molyneux and the author of the Essay are
not as far removed from my opinion as at first appears, and
perhaps the reasons for their view, which were apparently
contained in the letter of Mr. Molyneux, who had successfully
made use of them to convince people of their mistake, were
purposely suppressed by Mr. Locke so as further to exercise
the minds of his readers. If you will closely consider my
answer, you will find that I have included in it a condition
which may be taken to be implied in the question, that is,

178 LEIBNIZ AND LOCKE

that it is only a question of distinguishing; and that the
blind man knows that the two shaped bodies which he has to
distinguish are there, and therefore that each of the ap-
pearances he sees is either that of the cube or that of the
globe. In this case it seems to me certain that the blind
man who has just ceased to be blind can distinguish them
by the principles of reason, combined with what sensuous
knowledge he has previously acquired by touch. I am not
speaking of what he perhaps will do actually and on the spot;
for he will be dazzled and confused by novelty, as well as
little accustomed to drawing conclusions. The foundation
of my opinion is, that in the globe there are no points dis-
tinguished from the side of the globe itself, all of it being
uniform and without angles, whereas in the cube there are
eight points distinguished from all the others. If there were
not this method of distinguishing figures, a blind man could
not learn the rudiments of geometry by means of touch. Yet
we see that men born blind are capable of learning geometry,
and even have always some rudiments of a natural geometry;
moreover geometry is most often learnt simply by sight,
without the use of touch, as it could be, and indeed would have
to be, learnt in the case of a paralytic or any other person
who was more or less incapable of touch. And these two
geometries, the geometry of the blind man and that of the
paralytic, must meet and agree and even come back to the
same ideas, although they have no common images. This
shows again how necessary it is to distinguish images from
exact ideaSy which consist of definitions. Indeed, it would be
most interesting and even instructive thoroughly to examine
the ideas of a man born blind, and to hear his descriptions of
figures. For he can give such descriptions, and can even
understand the doctrine of optics, in so far as it is dependent
on ideas that are distinct and mathematical, although he
cannot manage to conceive anything which is chiaroscuro,
that is to say the image of light and colours. This is why a

LEIBNIZ AND LOCKE 179

certain man, born blind, after listening to some lessons on
optics, which he seemed to understand pretty well, when
asked what he thought about light replied that he imagined
it must be something pleasant like sugar. In the same way
it would be very important to examine the ideas of a man
born deaf and dumb about things without shapes, ideas
which we ordinarily describe in words, and which he must
acquire in a quite different way, although it may be equivalent
to ours, as the writing of the Chinese has the same effect as
our alphabet, although it is infinitely different from it, and
might seem to have been invented by a deaf man. I have
heard, through the courtesy of a great prince, of a man in
Paris, born deaf and dumb, whose ears finally came to perform
their proper office; this man has now learnt French (for it
was from the French Court that he was summoned not long
ago) and can tell many curious things about the conceptions
he had in his former state, and about the change in his ideas,
when his sense of hearing began to function. These people
who are born deaf and dumb can go further than we think.
There was one at Oldenburg in the time of the last count,
who became a good painter, and showed himself very rational
in other respects. A very learned man, Breton by nation-
ality, told me that at Blainville, a place ten leagues from
Nantes, belonging to the Duke of Rohan, there was about
1690 a poor man living in a hut, near to the castle outside
the town, who was born deaf and dumb, and who took letters
and other things to the town, finding the houses by means of
signs made him by the people who used to employ him. At
last the poor man became blind too, and still did not give up
performing services, and carrying letters to the town on the
strength of what he was told by touch. He had in his hut a
plank which went from the door to the place where his feet
were, and which made him aware by its movement when
any one came in. People are most negligent not to acquire
exact knowledge of the ways of thinking of such persons. If

i8o LEIBNIZ AND LOCKE

he is no longer alive, there is likely to be someone in the
vicinity who could still give us some information about him,
and make us understand how he was shown the things he
was to do. But to return to what the man born blind,
who is beginning to see, will think about the globe and the
cube, when he sees them without touching them, I answer
that he will distinguish them in the way I have said, if
someone informs him that one or the other of the appearances
or perceptions he has of them belongs to the cube or to the
globe; but without this preliminary instruction, I admit that
it would not at first occur to him to think that these sorts
of paintings which he received of them in the depths of his
eyes, and which might arise from a flat painting on the table,
represented bodies, until touch had convinced him of it, or
until, by dint of reasoning about rays according to the laws
of optics, he understood by the lights and the shadows that
there was something there which arrested these rays, and that
it was this which remained present to his sense of tcuch. He
would arrive at this view finally, when he saw the globe and
cube rolling along, and changing shadows and appearances
as the result of their motion, or even when, the two bodies
remaining at rest, the light which illuminated them changed
its place, or his eyes changed their position. For these are
more or less our methods of distinguishing at a distance
between a picture or a perspective representing a body, and
an actual body itself.

n. PH. Let us return to perception in general. Percep-
tion puts the difference between animals and inferior beings.

TH. I am inclined to think that there is some perception
and appetition in plants also, on account of the important
analogy which exists between plants and animals; and if
there is a vegetable soul, as is the common view, it must have
perception. But I none the less attribute to mechanism all
that takes place in the bodies of plants and animals, except
their original formation. Thus I agree that the motion of

LEIBNIZ AND LOCKE 181

the plant which is commonly called sensitive arises from
mechanism, and I do not approve of having recourse to the
soul for explaining the detail of the phenomena of plants
and of animals.

14. PH. It is true that I myself cannot but think that
even in such kinds of animals, as oysters and cockles,
there is some small dull perception : for would not quickness of
sensation be an inconvenience to an animal that must lie still
where chance has once placed it, and there receive the afflux of
colder or warmer, clean or foul water, as it happens to come to it ?

TH. Very true; and 1 hold that nearly as much could be
said of plants ; but as to man, his perceptions arc accompanied
by the power of reflection, which passes into action when
need arises. But when he is reduced to a state like that of one
who is in a lethargy, and is almost without sensation, reflec-
tion and apperception cease, and there is no longer any thought
of universal truths. Nevertheless, his faculties and dis-
positions, innate and acquired, and even the impressions he
has received in this state of confusion, do not for that reason
cease, and are not wiped out, even though they are forgotten;
they will even take their turn in contributing one day to some
notable result. For nothing in nature is useless; every con-
fusion is bound to be cleared up; the very animals, reduced to
a state of stupidity, must one day return to more exalted
perceptions; and since simple substances endure for ever, we
must not judge of eternity by a few years.

BOOK IV. OF KNOWLEDGE

CHAPTER II

Of the degrees of our knowledge

i . PH. Knowledge is intuitive when the mind perceives the
agreement or disagreement of two ideas immediately by them-
selves, without the intervention of any other. In this case the
mind is at no pains of proving or examining the truth. As

182 LEIBNIZ AND LOCKE

the eye sees the light, the mind sees that white is not black,
that a circle is not a triangle, that three is two and one.
This kind of knowledge is the clearest and most certain that
human frailty is capable of; it acts in a manner that is irre-
sistible, and it leaves no room in the mind for hesitation. It
is to know that the idea in the mind is such as it is perceived
to be. He that demands a greater certainty than this, demands
he knows not what.

TH. The primary truths which are known by intuition are
of two kinds, like derivative truths. They are either truths of
reason or truths of fact. Truths of reason are necessary,
those of fact are contingent. The primary truths of reason
are those which I call by the general name of identical, because
it appears that they do nothing but repeat the same thing,
without teaching us anything. They are affirmative or
negative. . . , l

Someone perhaps, after listening patiently to all that I
have just said, will at last lose patience and say that I am
amusing myself with frivolous enunciations, and that identical
truths serve no purpose whatever. But such a judgment
would be due to insufficient reflection on these matters. The
consequences of logic, for example, are proved by principles
which are identical; and geometry relies upon the principle
of contradiction in those demonstrations which reduce ad
impossibile. I will content myself here with showing the
value of identical propositions in the demonstrations of the
consequences of reasoning. I say then that the principle of
contradiction alone is sufficient to demonstrate the second
and third figures of the syllogism from the first. Take an
example in the first figure, in Barbara :

All B is C

All A is B

.'. all A is C.

1 Here follows about a page of instances of identical proposi-
tions, affirmative and negative, hypothetical, disjunctive, etc.

LEIBNIZ AND LOCKE 183

Let us suppose that the conclusion is false (or that it is true
that some A is not C), then the one or the other of the
premises will be false also. Suppose the second is true: then
the first, which asserts that all B is C, must be false. Then
its contrary will be true ; that is to say, some B is not C. And
this will be the conclusion of a new argument, drawn from
the falsity of the conclusion and the truth of one of the
premises of the preceding argument. Here is the new
argument:

Some A is not C

(which is opposite to the previous conclusion, supposed to
be false).

All A is B

(this is the previous premise, supposed to be true).
.'. some B is not C

(this is the present conclusion, which is true, the opposite of
the previous premise, which was false).

This argument is in the mood Disamis of the third figure,
which is thus demonstrated obviously and at a flash from the
mood Barbara of the first figure, without involving anything
but the principle of contradiction. And I observed in my
youth, when I was criticizing these things, that all the moods
of the second and third figures can be obtained from the
first by this one method, if we suppose that the mood of the
first is valid, and consequently that, the conclusion being
falst' and its contrary being taken for true, and one of the
premises being taken for true also, it follows that the contrary
of the other premise must be true. It is true that in the
Schools of logic they prefer to make use of conversions. 1 . . .

1 The validity of conversions themselves, Leibniz says, must be
demonstrated from the primary principle, that of contradiction ;
it is therefore better to demonstrate the second and third figures
direct, as above, and not to use conversion.

184 LEIBNIZ AND LOCKE

Since the demonstration of conversions also shows the value
of identical affirmative propositions, which some take to be
utterly frivolous, it is all the more relevant to include it here.
I will only mention conversions without contraposition,
which are sufficient for my purpose here, and which are either
simple or per accidens, as they are called. Simple conver-
sions are of two kinds: the universal negative, like No
square is obtuse-angled, therefore no obtuse-angled figure is
square ; and the particular affirmative, such as Some triangles
are obtuse-angled, therefore some obtuse-angled figures are
triangles. But conversion per accidens, as it is called,
concerns the universal affirmative, such as All squares are
rectangles, therefore some rectangles are squares. By rectangle
here is always understood a figure whose angles are right
angles, and by square a regular quadrilateral. We have now
to demonstrate these three kinds of conversions, which are:

(1) No A is B, :. no B is A.

(2) Some A is B, .*. some B is A.

(3) All A is B, .'. some B is A.

Demonstration of the first conversion in Cesare, which is of
the second figure:

No A is B

All B is B
.'. no B is A.

Demonstration of the second conversion in Datisi, which is
of the third figure:

All A is A

Some A is B
/. some B is A.

Demonstration of the third conversion in Darapti, which is
of the third figure:

All A is A

All A is B
:. some B is A.

LEIBNIZ AND LOCKE 185

This shows that identical propositions which are most pure
and appear to be most useless have considerable value in the
abstract and in general. And that should teach us not to
despise any truth. As regards the proposition that three is
equal to two and one, which you adduce, Sir, as an example of
intuitive knowledge, my comment is that it is simply the
definition of the term three \ for the simplest definitions of
numbers are formed in this manner two is one and one,
three is two and one, Jour is three and one, and so on. It
is true that there is hidden within these definitions an
enunciation, which I have already mentioned, namely that
these ideas are possible; and that is known in this case
intuitively, so that we may say that there is intuitive know-
ledge contained in definitions when their possibility first
appears. And in this way all adequate definitions contain
primary truths of reason, and consequently intuitive know-
ledge. Finally, we may say in general that all primary
truths of reason are immediate with an immediacy of ideas.

As regards primary truths of fact, these are the immediate
internal experiences of an immediacy of sensation. It is
among these that is included the first truth of the Cartesians
or of Saint Augustine : / think, therefore I am, that is to say,
/ am a thing which thinks. But it is to be noted that the
same is true of primary truths of fact as of identicals, that is
to say that they can be either general or particular, and are
as clear in the one case as in the other (since it is as clear to
say that A is A as to say that a thing is what it is.) For not
only is it clear to me immediately that I think, but it is just
as clear to me that I have different thoughts, that now / think
of A and now / think of B, etc. Thus the Cartesian principle
is sound, but it is not the only one of its kind. So we see
that all primary truths of reason or of fact have this in com-,
mon that they cannot be proved by something more certain.

2. PH. I am very much pleased, sir, that you have
developed further my remarks, in which I did no more than

186 LEIBNIZ AND LOCKE

touch upon intuitive knowledge. Now demonstrative know-
ledge is simply a linking together of intuitive apprehensions
in all the connections of the mediate ideas. For often the
mind cannot join, compare, or apply its ideas to one another
immediately, and so it is obliged to make use of other
mediating ideas (one or more, as it happens) in order to
discover the agreement or disagreement it is looking for; and
this is called reasoning. For instance, in demonstrating that
the three angles of a triangle are equal to two right angles, it
finds out some other angles which it sees to be equal both to
the three angles of the triangle and to two right angles.
3. These intervening ideas are called proofs] and a quick-
ness of the mind to find them is what is called sagacity. 4.
Even when these ideas have been found, it is not without
pains and attention, nor by a single transient view, that this
knowledge can be acquired; there must be a progression of
ideas by steps and degrees. 5. Before the demonstration
there is a doubt. 6. It is less clear than intuitive know-
ledge; just as a face reflected by several mirrors one to
another grows weaker and weaker at each successive reflec-
tion, and is not at first sight so knowable, especially to weak
eyes. Thus it is with knowledge made out by a long train of
proof. 7. And though in each step which reason makes in
demonstrating there is an intuitive knowledge, or knowledge
at sight, yet because in this long succession of proofs the
memory does not retain so exactly this chain of ideas, men
often embrace falsehoods for demonstrations.

TH. Over and above sagacity, whether natural or acquired
by exercise, there is an art of finding mediating ideas (the
medium)] and this art is Analysis. Now it is well to con-
sider here that it is sometimes a question of finding out the
truth or falsity of a given proposition, that is, simply to
answer the question whether ? that is to say, Is it or is it
not? At other times it is a matter of answering a question
which is much more difficult (ceteris paribus); for instance,

LEIBNIZ AND LOCKE 187

where it is asked by what means ? or how ? and where there is
more to be supplied. It is these questions only, which leave
part of the proposition blank, which mathematicians call
problems: for instance when we are asked to find a mirror
which collects all the rays of the sun at a point ; that is to say
we are asked its shape, or how it is made. As for the first
kind of questions, where it is simply a matter of true and
false, and where there is nothing to supply in the subject or
predicate, here there is less invention; still there is some, and
judgment alone is not sufficient. It is true that a man of
judgment, that is to say, one who is capable of attention and
restraint, and who has the necessary leisure and patience and
is open-minded enough, can understand the most difficult
demonstration if it is properly put to him. But the most
judicious man in the world will not always be able to find
the demonstration without assistance. Thus there is some
invention in that too; and in geometry there used to be more
in earlier times than there is now. For when the art of
Analysis was less cultivated, it required more sagacity to
arrive at it. ... It also happens that induction provides us
with some truths about numbers and figures, for which the
general reason has not yet been discovered. For we are
far from having arrived at the perfection of Analysis in
geometry and in numbers. . . .

But it is much more difficult to find out important truths,
and even more so to find out means of doing what is wanted,
just when it is wanted, than it is to find out the demonstration
of what someone else has discovered. Often beautiful truths
are arrived at by Synthesis, by passing from the simple to the
compound; but when it is a matter of finding out exactly the
means for doing what is required, Synthesis is ordinarily not
sufficient ; and often a man might as well try to drink up the
sea as to make all the required combinations, even though it
is often possible to gain some assistance from the method of
exclusions, which cuts out a considerable number of useless

188 LEIBNIZ AND LOCKE

combinations; and often the nature of the case does not
admit of any other method. But there are not always
available the means for properly following this method. So
it is to Analysis that we must look for a thread in the laby-
rinth, whenever it is possible; for there are cases where the
very nature of the question requires that we should proceed
by trial and error throughout, short cuts not always being
possible.

8. PH. Now since demonstration always presupposes
intuitive knowledge, it is this, I imagine, which gave occasion
to the axiom that all reasoning is from things previously known
and previously granted (ex praecogmtis et praeconcessis). But
we shall have occasion to speak of the faults of this axiom,
when we come to speak of the maxims which are mistakenly
supposed to be the foundations of our reasonings.

TH. I shall be curious to learn what fault you can find
with an axiom which appears so reasonable. If it was
necessary to reduce everything to intuitive apprehensions,
demonstrations would often be of unbearable prolixity. . . .
But there is another hindrance, namely that it is not easy to
demonstrate all the axioms, and entirely to reduce demon-
strations to intuitive apprehensions. And if attempts had
been made to do this, perhaps ue should still be without the
science of geometry. . . .

14. PH. Besides intuition and demonstration) which are
the two degrees of our knowledge, all the rest is faith or
opinion, but not knowledge, at least in all general truths. There
is, however, another perception of the mind employed about the
particular existence of finite beings without us ; and this is
called sensitive knowledge. . . .

Sensitive knowledge, or the knowledge which establishes the
existence of particular beings without us, goes beyond bare
probability; but it does not possess all the certainty of the
two degrees of knowledge of which we have been speaking.
There can be nothing more certain than that the idea we receive

LEIBNIZ AND LOCKE 189

from an external object is in our minds. But whether we can
thence certainly infer the existence of anything without us which
corresponds to that idea, is that whereof some men think there
may be a question made ; because men may have such ideas in
their minds when no such thing exists, no such object affects
their senses. But yet here I think we are provided with an
evidence which puts us past doubting. We are invincibly
conscious of a different perception when we look on the sun
by day and think on it by night; and the idea which is revived
by the aid of memory is very different from the one which
actually comes into our minds by our senses. If any one says
a dream may do the same thing, I make him this answer: (i)
That it is no great matter whether 1 remove this scruple or no:
where all is but dream, reasoning and arguments are of no use,
truth and knowledge nothing. (2) That I believe he will allow
a very manifest difference between dreaming of being in the
fire and being actually in it. And if he persists in appearing
sceptical, I will tell him that it is enough that we certainly
find that pleasure or pain follows upon the application of
certain objects to us, whose existence we perceive, or dream that
we perceive, by our senses: this certainty is as great as our
happiness or misery ; beyond which we have no concernment to
know or to be. So that I think we may reckon three degrees of
knowledge ; viz., intuitive, demonstrative, and sensitive.

TH. I believe you are right, and I even think that to these
kinds of certainty or certain knowledge you might add know-
ledge of the probable] thus there will be two sorts of knowledge
as there are two sorts of proofs, of which the one produces
certainty, while the other arrives at probability only. But let
us turn to the quarrel between the Sceptics and the Dog-
matists over the existence of things without us. We have
already touched upon it, but we must return to it here. I have
in the past had much argument about this both personally
and by letter with the late M. PAbb6 Foucher, Canon of
Dijon, a man both learned and subtle, but somewhat too

igo LEIBNIZ AND LOCKE

much engrossed in the Academics, whose sect he would gladly
have revived, just as M. Gassendi brought back upon the
scene the sect of Epicurus. His criticism of the Recherche de
la Verite, and other small treatises which he had printed
subsequently, have brought their author some fame. He
also published in the Journal des Savans some objections to
my System of Pre-established Harmony, when I communi-
cated it to the public, after meditating on it for some years;
but death prevented him from answering my reply. He
always preached that we ought to guard against prejudices
and to insist on great exactitude; but not only did he not
devote himself to practising what he preached, wherein he
was excusable enough, but he also seemed to me not to heed
whether others did so, foreseeing no doubt that no one ever
would. Now I pointed out to him that the truth of sensible
things only consisted in the connection of phenomena, for
which there must be a reason, and which is the thing that
distinguishes them from dreams; but that the truth of our
existence and of the cause of phenomena is of another nature,
because it establishes some substances. I urged that the
Sceptics spoil what is good in their statements, by carrying
them too far, even wishing to extend their doubts to im-
mediate experiences, and even to geometrical truths (which,
however, M. Foucher did not do), and to other truths of
reason, which he did a little too much. But, to return to you,
Sir, you are right in saying that there is a difference ordinarily
between sensations and imaginings; but the Sceptics would
say that a difference of more and less is not a difference
of kind. Besides, though sensations are habitually more
vivacious than imaginings, there are none the less cases where
imaginative people are as much or perhaps more struck by
their imaginings than others are by the truth of things; so
that I hold that the true criterion regarding the objects of the
senses is the connection between phenomena, that is to say
the linking up of what occurs in different places and times,

LEIBNIZ AND LOCKE 191

and in the experience of different men, who are themselves
very important phenomena to one another in this regard.
And the connection of phenomena, which guarantees truths
of fact with regard to sensible things outside us, is verified by
means of truths of reason-, as appearances in optics have light
thrown upon them by geometry. Still it must be admitted
that none of this certitude is of the highest order, as you have
rightly recognized. For it is not impossible, metaphysically
speaking, for there to be a dream which is consecutive and
enduring like the life of a man; but it is a thing as contrary
to reason as it would be for a book to be composed by chance
through the type being jumbled up together anyhow. Besides
it is also true, that provided phenomena are linked up, it
matters not whether they are called dreams or not, since
experience shows that we are not mistaken in the measures
we take with phenomena, when they are taken in accordance
with the truths of reason.

15 PH. For the rest, knowledge is not always clear, where
the ideas are so. A man that has as clear ideas of the angles of a
triangle, and of equality to two right ones, as any mathematician
in the world, may yet have but a very obscure perception of their
agreement.

TH. Usually, when ideas are fundamentally understood,
their agreements and disagreements appear. Nevertheless,
I admit that there are sometimes ideas so compounded that
much care is needed to develop what is hidden in them; and
considering this, some agreements and disagreements may
still remain obscure. As to your example, my comment is that
the fact that we have the angles of a triangle in the imagina-
tion does not mean that we therefore have clear ideas of them.
Imagination is incapable of providing us with an image
common to acute-angled and obtuse-angled triangles, and
yet the idea of triangle is common to both. Thus this idea does
not consist in the images, and it is not as easy as one might
think fundamentally to understand the angles of a triangle.
P95

CORRESPONDENCE WITH CLARKE l

LEIBNIZ'S FIRST PAPER a
(Extract from a letter written in 'November 1715)

IT appears that even natural religion is growing very much
weaker. Many hold that souls are corporeal ; others hold that
God Himself is corporeal. Mr. Locke and his followers are
at any rate doubtful whether souls are not material and
naturally perishable. Mr. Newton says that space is the
organ which God makes use of to perceive things by. But
if He stands in need of any medium whereby to perceive them,
they do not then depend entirely on Him, and were not
produced by Him. Mr. Newton and his followers have also
an extremely odd opinion of the work of God. According
to them God has to wind up His watch from time to time. 3
Otherwise it would cease to go. He lacked sufficient fore-
sight to make it a perpetual motion. This machine of God's
is even, on their view, so imperfect that He is obliged from
time to time to come to its assistance especially out of the

1 Samuel Clarke (1675-1729), English philosopher and divine;
the most celebrated disciple of Newton.

* This paper by Leibniz begins the correspondence. It is
given here complete.

Clarke thinks that the passage to which Leibniz is referring
is the following, from Newton's Optics: ' Whilst the comets move
in orbs very eccentrical, with all variety of directions towards
every part of the heavens; 'tis not possible it should have been
caused by blind fate, that the planets all move with one similar
direction in concentrick orbs; excepting only some very small
irregularities, which may have arisen from the mutual actions of
the planets and comets upon one another; and which 'tis
probably will in length of time increase more and more, till the
present system of nature shall want to be anew put in order by
its Author.' (The translation from Newton's Latin is Clarke's.)

192

LEIBNIZ AND CLARKE 193

ordinary course, and clean it, and even to mend it, as a clock-
maker might his handiwork; and the less skilful the workman
is, the more often is he obliged to rehandle and correct his
work. According to my view, the same force and vigour
goes on existing in the world always, and simply passes from
one matter to another, according to the laws of nature and to
the beautiful pre-established order. And I hold that, when
God performs miracles, it is not to uphold the needs of nature,
but for those of grace. To think otherwise would be to
have a very low opinion of the wisdom and power of God.

LEIBNIZ'S SECOND PAPER 1

It is rightly said in the Paper which was sent to the Princess
of Wales, and which Her Royal Highness did me the honour
of sending me, that next to vicious passions the principles of
the Materialists contribute much to support impiety. But I
do not think the author was justified in adding that the
Mathematical Principles of philosophy are opposed to those of
the Materialists. On the contrary, they are the same except
that Materialists follow the example of Democritus, Epicurus,
and Hobbes, and restrict themselves to mathematical prin-
ciples alone and admit nothing but bodies; while the Christian
Mathematicians admit immaterial substances also. Thus
it is not Mathematical Principles (in the ordinary sense of the
term) but Metaphysical Principles which must be opposed
to those of the Materialists. Pythagoras, Plato, and to some
extent Aristotle had some knowledge of these, but it is my
claim to have established them demonstratively, although
I was giving a popular exposition, in my Theodicy. The
great foundation of mathematics is the principle of contra-
diction or of identity, that is to say, that a statement cannot
be true and false at the same time and that thus A is A, and

1 This Second Paper was written in answer to Clarke's reply to
Leibniz's First Paper. It is given here complete.

194 LEIBNIZ AND CLARKE

cannot be not A. And this single principle is enough to
prove the whole of arithmetic and the whole of geometry,
that is to say all mathematical principles. But in order to
proceed from mathematics to physics another principle is
necessary, as I have observed in my Theodicy, that is, the
principle of a sufficient reason, that nothing happens
without there being a reason why it should be thus rather
than otherwise. This is why Archimedes, wishing to proceed
from mathematics to physics in his book On Equilibrium, was
compelled to make use of a particular case of the great
principle of sufficient reason; he takes it for granted that if
there is a balance in which everything is the same on both
sides, and if, further, two equal weights be hung on the two
ends of the balance, the whole will remain at rest. This is
because there is no reason why one side should go down
rather than the other. Now by this principle alone, to wit, that
there must be a sufficient reason why things are thus rather
than otherwise, is proved Divinity, and all the rest of meta-
physics and natural theology, and even in some manner
those physical principles which are independent of mathe-
matics, that is to say, the principles of dynamics or of
force.

Our author goes on to say that according to the mathe-
matical principles, that is to say according to the philosophy
of Mr. Newton (for mathematical principles here prove
nothing one way or the other), matter is the least considerable
part of the universe. This is because he holds that besides
matter there is empty space, and because according to him
matter only occupies a very small part of space. But
Democritus and Epicurus maintained the same thing, except
that in this they differed from Mr. Newton on the point of
quantity; according to them there was perhaps more matter
in the world than according to Mr. Newton. Wherein I
think their view is preferable; for the more matter there is,
the more opportunity is there for God to exercise His wisdom

LEIBNIZ AND CLARKE 195

and His power; and it is for this, among other reasons, that I
hold that there is no void at all.

It is said expressly in the Appendix to Mr. Newton's
Optics that space is God's sensorium. 1 Now the word
sensorium has always meant the organ of sensation. Let him
and his friends now give a quite different explanation of their
meaning: I shall not object.

Our author supposes that the presence of the soul is enough
to enable it to perceive what is going on in the brain. But
this is exactly what Malebranche and the whole Cartesian
School deny, and rightly deny. Something quite other than
mere presence is needed for one thing to represent what takes
place in another. For this some explicable communication
is necessary, some kind of influence either of the things upon
one another or of a common cause. Space, according to Mr.
Newton, is intimately present to the body which it contains
and which is commensurate with it. Does it therefore
follow that space perceives what takes place in the body, and
remembers it after the body has left it? Besides, since the
soul is indivisible and its immediate presence in the body
could therefore be conceived to be at a point only, how could
it then perceive what took place outside this point ? I claim
to be the first to have shown how the soul perceives what
takes place in the body.

The reason why God perceives everything is not His
simple presence, but His operation also; it is because He
preserves things by an activity which continually produces
all that there is in them of goodness and perfection. But
since souls have no immediate influence on bodies, nor bodies
on souls, their mutual correspondence cannot be explained
by presence.

The real reason which chiefly causes us to praise a

1 Clarke had objected to Leibniz's statement in his First Paper
that ' Mr. Newton says that space is the organ which God makes
use of to perceive things by '. Cf . p. 192.

196 LEIBNIZ AND CLARKE

machine, is derived rather from the effect of the machine
than from its cause. We seek information less regarding
the power of the mechanician than regarding his in-
vention. Thus the reason alleged for praising God's
machine that He made it entirely without borrowing any
matter from outside is not enough. It is a shift to which
the author has been compelled to resort. The reason why
God is to be preferred above another mechanician is not
only because He makes the whole, whereas the artisan has
to seek for his material. This superiority would arise from
power only. But there is another reason for the excellence
of God, which arises from wisdom. This reason is that His
machine also lasts longer and goes more correctly than that
of any other mechanician whatever. The buyer of the watch
does not trouble himself whether the workman made the
whole of it, or whether he had the pieces of it made by other
workmen and merely adjusted them himself, provided that
it goes properly. And if the workman had received from God
the gift of creating as well the material for the wheels, the
buyer would not be satisfied if he had not also received the
gift of adjusting them properly. And in the same way the
man who wants to be satisfied with God's handiwork will
not become so merely for the reason alleged here.

Thus it is needful that God's invention should not be
inferior to that of a workman; it must even go infinitely
beyond it. The mere production of everything would indeed
exemplify the power of God, but it would not sufficiently
show His wisdom. Those who maintain the opposite fall
exactly into the error of the Materialists and of Spinoza,
from whom they protest they differ. They recognize power,
but not sufficient wisdom in the principle of things.

I do not say that the corporeal world is a machine or watch
which goes without God's interposition, 1 and I am insistent

1 Clarke had made the (usual) objection to Leibniz : ' The notion
of the world's being a great machine, going on without the inter-

LEIBNIZ AND CLARKE 197

enough that created things stand in need of His continual
influence. But 1 do maintain that it is a watch which goes
without needing His correction: otherwise we should have to
admit that God keeps improving upon His own work. God
has foreseen everything, He has provided a remedy for every-
thing in advance. There is in His works an already pre-
established harmony and beauty.

This view does not exclude the providence or the govern-
ment of God: on the contrary it makes it perfect. A true
providence in God requires a perfect foresight, but moreover
it further requires not only that He should have foreseen
everything but also that He should have provided for every-
thing by means of suitable preordained remedies: otherwise
He would lack either wisdom to foresee things or power to
provide for them. He would be like the God of the Socinians,
who lives from day to day, as M. Jurieu said. It is true that
God, according to the Socinians, fails even to foresee defects,
whereas, according to these gentlemen who force Him to
correct Himself, He fails to provide for them. But this
seems to me to be still a very great lack; He would have to
lack either power or good will.

I do not think I can be justly rebuked for having said
that God is Intelligentia Supramundana. Will those who dis-
approve of it say He is Intelligentia Mundana, that is to say
the Soul of the World? I hope not. However, they would
do well to take care not to slip into this unintentionally.

The comparison with a king in whose kingdom everything
went on without his interference is not to the point, since
God preserves things continually, and since they cannot
subsist without Him: thus His Kingdom is not a nominal one.
To say this would be like saying that a king who had his

position of God, as a clock continues to go without the assistance
of a clockmaker, is the notion of Materialism and Fate, and tends
(under pretence of making God a Supra - mundane Intelligence)
to exclude Providence and God's government in reality out of
the world*.

ig8 LEIBNIZ AND CLARKE

subjects so well educated, and by his care in providing for
their subsistence, preserved them so well in their fitness for
their several stations and in their good affection towards
him, that he had no occasion ever to be amending anything
amongst them, was only a nominal king.

Finally, if God is obliged to correct natural things from
time to time, this must occur either supernaturally or
naturally. If it occurs supernaturally, recourse is had to
miracles to explain natural things; which is in effect a
reductio ad absurdum of a hypothesis. For by miracles,
anything can easily be accounted for. But if it occurs
naturally, God will not be Intelligentia Supramundana, He
will be included in the nature of things, that is to say, He
will be the Soul of the World.

LEIBNIZ'S THIRD PAPER l

1. According to the usual way of speaking, mathematical
principles 2 are those which consist in pure mathematics,
for instance numbers, figures, arithmetic, geometry. But
metaphysical principles concern more general notions, as for
example cause and effect.

2. I am granted this important principle, that nothing
happens without a sufficient reason why it should be thus rather
than otherwise. But it is granted me in words and refused
me in fact; which shows that the full force of it has not been
properly understood ; and in this connection the author makes

1 Written in answer to Clarke's reply to the Second Paper. It
is given here complete.

'Clarke had argued that the Mathematical Principles of
Philosophy (i.e. Newton's philosophical doctrines) are opposed to
Materialism because they demonstrate that the existing state of
things can only have arisen from an Intelligent and Free Cause.
As regards the propriety of the name ; he says : ' So far as meta-
physical consequences follow demonstratively from mathe-
matical principles, so far the mathematical principles may
(if it be thought fit) be called metaphysical principles '.

LEIBNIZ AND CLARKE 199

use of an example which exactly falls in with one of my
demonstrations against real absolute space, the idol of some
modern Englishmen. I call it 'idol* not in a theological
sense, but in the philosophical sense in which Chancellor
Bacon used the word when he said, a long time ago, that
there are idola tribus, idola specus. 1

3. These gentlemen maintain, then, that space is a real
absolute being; but this leads them into great difficulties.
For it appears that this being must be eternal and infinite.
This is why there have been some who believed that it was
God Himself, or else His attribute, His immensity. But as
it has parts, it is not a thing which can be appropriate
to God.

4. As for me, I have more than once stated that I held
space to be something purely relative, like time; space being
an order of co-existences as time is an order of successions.
For space denotes in terms of possibility an order of things
which exist at the same time, in so far as they exist together,
and is not concerned with their particular ways of existing:
and when we see several things together we perceive this
order of things among themselves.

5. I have several proofs for refuting the conception of
those who take space to be a substance, or at least an absolute
being of some kind. But here I only wish to make use of
the one which the present occasion requires. I say then
that if space were an absolute being, there would happen
something for which it would be impossible that there should
be a sufficient reason, and this is contrary to our axiom. This
is how I prove it. Space is something absolutely uniform,
and without the things situated in it one point of space
absolutely does not differ in any respect from another point
of space. Now from this it follows that if we suppose that
space is something in itself, other than the order of bodies
among themselves, it is impossible that there should be a

1 'idols of the tribe, idols of the cave.'

200 LEIBNIZ AND CLARKE

reason why God, preserving the same positions for bodies
among themselves, should have arranged bodies in space
thus and not otherwise, and why everything was not put
the other way round (for instance) by changing east and west.
But if space is nothing other than this order or relation, and
is nothing whatever without bodies but the possibility of
placing them in it, these two conditions, the one as things are,
the other supposed the other way round, would not differ
from one another: their difference exists only in our chimerical
supposition of the reality of space in itself. But in truth the
one would be just the same as the other, as they are abso-
lutely indiscernible; and consequently there is no occasion
to search after a reason for the preference of the one to the
other.

6. The same is true of time. Suppose someone asks why
God did not create everything a year sooner; and that the
same person wants to infer from that that God did something
for which He cannot possibly have had a reason why He did
it thus rather than otherwise, we should reply that his
inference would be true if time were something apart from
temporal things, for it would be impossible that there should
be reasons why things should have been applied to certain
instants rather than to others, when their succession remained
the same. But this itself proves that instants apart from
things are nothing, and that they only consist in the succes-
sive order of things; and if this remains the same, the one
of the two states (for instance that in which the creation was
imagined to have occurred a year earlier) would be nowise
different and could not be distinguished from the other which
now exists.

7. It will be seen from everything I have said that my
axiom has not been fully understood, and that the author,
while appearing to grant it, has really denied it. // is true,
he says, that nothing exists without a sufficient reason why it is
thus rather than otherwise, but he adds that this sufficient

LEIBNIZ AND CLARKE 201

reason is often the simple or mere will of God, as when it is
asked why matter was not differently arranged in space,
the positions as between bodies being preserved. But this
is simply maintaining that God wills something without there
being a sufficient reason for His will, contrary to the axiom
or general rule governing everything which happens. This
is to relapse into the loose indifference which I have amply
refuted, and which I have shown to be absolutely chimerical,
even in created beings, and contrary to the wisdom of God,
as if He could operate without acting reasonably.

8. I am met with the objection that not to admit this
simple and mere will would be to remove from God the power
of choice, and that this would be to fall into fatalism. But
quite the reverse is true. I maintain that God has the power
of choice, since I base it on the reason for the choice which is
in conformity with His wisdom. And it is not this fatalism
(which is nothing but the order of the highest wisdom or of
providence) but a brute fatalism or necessity, in which there
is neither wisdom nor choice, that we ought to avoid.

9. I had observed that if we diminish the quantity of
matter, the quantity of objects on which God can exercise
His goodness is diminished. The author answers that in-
stead of matter there are other things in the void on which
He does not fail to exercise it. Be it so; though I do not
agree, for I hold that all created substance is accompanied
by matter. But be it so. I answer that more matter was
compatible with those same things, and consequently the said
object will still be lessened. The example of a greater
number of men or animals is not to the purpose, for they
would occupy the room of other things.

10. It will be difficult to make me believe that, in its
ordinary use, sensorium does not mean the organ of sensation.
Here are the words of Rudolphus Gocleniiu, in his Philoso-
phical Dictionary: Sensiterium: barbarum Scholasticorum
(he says) qui interdum sunt simiae Graecorum. Hi dicunt

202 LEIBNIZ AND CLARKE

ex quo illi fecerunt Sensiterium pro Sensorio, id
estj organo sensationis. 1

11. The simple presence of a substance, even an animated
one, is not enough for perception: a blind man does not see,
nor even does an absent-minded one. It is necessary to
explain how the soul perceives what is outside itself.

12. God is not present in things by situation but by
essence; His presence is manifested by His immediate
operation. The presence of the soul is of quite another
nature. To say that it is diffused throughout the body is to
make it extended and divisible; to say that the whole of it
exists in each part of each body is to make it divisible from
itself. To attach it to one point, to spread it over several
points are only improper expressions, idola tribus?

13. If active force were lost in the universe by the natural
laws which God has established in it, so that He needed a
new impression to restore this force, like a workman setting
right the imperfection of his machine, the disorder would
occur not only with regard to us, but with regard to God
Himself. He could have prevented it and have taken better
steps to avoid such an untoward occurrence. Actually,
indeed, He has done so.

14. When I said that God has prepared actual remedies
against these disorders in advance, I do not mean that God
lets the disorders come and then the remedies for them; but
that He has found means in advance to prevent disorders
from happening.

15. Our author attempts without success to criticize my
expression, that God is Intelligentia Supramundana. To say
that He is above the world is not to deny that He is in the
world.

1 ' Sensiterium: a barbarism of the Scholastics, who sometimes
ape the Greeks. The latter say alcrQifT-fipior , from which the
former have manufactured the word sensitenum in place of
sensorium, i.e. the organ of sensation/

1 Cf note, p. 199.

LEIBNIZ AND CLARKE 203

16. I have never given occasion for doubt whether God's
conservation is an actual preservation and continuation of
beings, powers, orders, dispositions, and motions; and I
think I have perhaps explained it better than many others.
But, says our author, this is all that I contended Jor : herein
consists the whole dispute. To this I answer: Your most
humble servant. Our dispute consists in quite different
things. The question is whether God does not act in the
most regular and perfect manner; whether His machine is
liable to disorders which He will be obliged to set right by
extraordinary means; whether the will of God is capable
of acting without reason; whether space is an absolute
being; wherein consists the nature of miracles: and many
similar questions which set a great gulf between us.

17. Theologians will not agree with the thesis advanced
against me, that there is no difference in relation to God
between the natural and the supernatural. The majority of
philosophers will approve it even less. There is an infinite
difference, but it certainly seems not to have been given
proper consideration. The supernatural surpasses all the
powers of created things. We must take an example. Here
is one which I have often made use of with success. If God
wished to cause a free body to circle in the ether round about
a given fixed centre, without any other created thing acting
on it, this, I say, could only occur by miracle, not being
explicable by the nature of bodies. For a free body natur-
ally departs from a curve along the tangent. It is in this
sense that I maintain that the attraction of bodies, properly
so called, is a miraculous thing, since it cannot be explained
by their nature.

LEIBNIZ'S FOURTH PAPER l

i. In things which are absolutely indifferent there can be

1 Written in answer to Clarke's reply to the Third Paper. As
will be seen, some paragraphs have been omitted here.

204 LEIBNIZ AND CLARKE

no choice and consequently no election or will, since choice
must have some reason or principle.

2. A simple will without any motive (a mere will) is a
fiction which is not only contrary to the perfection of God,
but also chimerical and contradictory, incompatible with the
definition of will and sufficiently refuted in my Theodicy.

3. It is indifferent whether three bodies which are equal
and alike in every respect be placed in any order whatsoever,
and consequently they never would be placed in order by
Him who does nothing without wisdom. But also, being the
Author of things, He will not produce any such; and conse-
quently there are none in nature.

4. There are no two individuals indiscernible from one
another. A clever gentleman, a friend of mine, when con-
versing with me in the presence of Her Electoral Highness 1
in the garden at Herrenhausen, thought he would cer-
tainly find two leaves exactly alike. Her Electoral Highness
challenged him to do so, and he spent a long time running
about looking for them, but in vain. Two drops of water or
milk looked at under the microscope will be found to be
discernible. This is an argument against atoms, which, like
the void, are opposed to the principles of a true metaphysic.

5. These great principles of a Sufficient Reason and of the
Identity of Indiscernibles change the state of metaphysics,
which by their means becomes real and demonstrative;
whereas formerly it practically consisted of nothing but
empty terms.

6. To suppose two things indiscernible is to suppose the
same thing under two names. Thus the hypothesis that the
universe should have originally had another position in time
and place from that which it actually had, and yet all the
parts of the universe should have had the same position with
regard to one another as that which they have in fact re-
ceived, is an impossible fiction.

1 Sophia, Electress of Hanover, mother of George I of England.

LEIBNIZ AND CLARKE 205

7. The same reason which shows that space outside the
world is imaginary proves that all empty space is something
imaginary; for they differ only as the great from the small.

8. If space is a property or an attribute, it must be
the property of some substance. Of what substance is the
bounded empty space, which the supporters of this view
suppose to exist between two bodies, the property or affection ?

9. If infinite space is immensity, finite space will be the
opposite of immensity, that is to say mensurability or
bounded extension. Now extension must be the affection
of something extended. But if this space is empty, it will
be an attribute without a subject, an extension of no extended
thing. This is why in making space a property the author
is accepting my position, according to which it is an order of
things and not something absolute.

10. If space is an absolute reality, far from being a property
or accident opposed to substance, it will have more sub-
sistence than substances; God will be unable to destroy it,
or even to change it in any respect. It will be not only
immense in the whole, but also immutable and eternal in
each of its parts. There will be an infinity of eternal things
besides God.

11. To say that infinite space is without parts, is to say
that it is not made up of finite spaces, and that infinite space
might continue to exist though all finite spaces were reduced
to nothing. It would be as if we were to say, on the Cartesian
supposition of a corporeal extended universe without limits,
that this universe might continue to exist though all the
bodies which make it up were reduced to nothing.

13. To say that God could move the universe forward in a
straight line or otherwise without changing it in any other
way is another chimerical supposition. For two indiscernible
states are the same state, and consequently it is a change
which changes nothing. Further, there is no rhyme nor

206 LEIBNIZ AND CLARKE

reason in it. Now God does nothing without a reason, and
it is impossible that there should be one here. Besides, it
would be agenda nihil agere, 1 as I have just said, because of
the indiscernibility.

14. These are idola tribus, 2 the purest chimeras and super-
ficial imaginings. It is all founded merely on the supposition
that imaginary space is real.

15. It is a similar, that is to say an impossible, fiction to
suppose that God had created the world several million years
sooner. Those who incline towards such kinds of fiction
will be unable to reply to those who argue in favour of the
eternity of the world. For since God does nothing without a
reason, and since there is no reason assignable why He did not
create the world sooner, it will follow either that He created
nothing at all, or that He produced the world before any
assignable time, which is to say that the world is eternal.
But when we show that the beginning, whatever it was,
is always the same thing, the question why it was not other
wise ceases to arise.

16. If space and time were something absolute, that is to
say if they were something other than certain orders of
things, what I am saying would be a contradiction. But
since this is not the case, the hypothesis is contradictory,
that is to say it is an impossible fiction.

17. It is very like what happens in geometry where, by
the very supposition that a figure is greater, we sometimes
prove that in fact it is not greater. It is a contradiction;
but the contradiction is in the hypothesis, which for this
very reason is shown to be false.

18. The uniformity of space means that there is neither
internal nor external reason for discerning its parts, and
for choosing between them. For such external reason for
discerning could only be founded in the internal one; other-

1 'acting without doing anything'.
1 Cf. p. 199, note.

LEIBNIZ AND CLARKE 207

wise it would be discerning the indiscernible, or choosing
without discerning. Will without reason would be the
'chance' of the Epicureans. A God who acted by such a
will would be a God only in name. The source of these
errors is want of care to avoid what is derogatory to the
Divine perfections.

19. When two incompatible things are equally good, and
when one has no advantage over the other either in itself
or in its combination with others, God will produce neither.

20. God is never determined by external things, but always
by what is in Himself, that is to say by His knowledge, before
anything exists outside Him.

21. There is no possible reason which could limit the
quantity of matter. Therefore there cannot in fact be any
such limitation.

22. And suppose such an arbitrary limitation did exist, it
would always be possible to add something without dero-
gating from the perfection of those things which already
exist: and consequently it would always be necessary to
add something, in order to accord with the principle of the
perfection of Divine operations.

23. Thus it cannot be said that the present quantity of
matter is the most fitting for the present constitution of
things. And even if this were the case, it would follow that
this present constitution of things would not be the most
fitting absolutely, if it prevents the employment of more
matter; it would therefore be necessary to choose another
constitution of things, capable of something more.

29. God perceives things in Himself. Space is the place of
things, and not the place of the ideas of God: unless we
consider space as something which causes the union of
God and things, in imitation of the imagined union of
the soul and the body; which would still make God the
Soul of the World.
Q95

208 LEIBNIZ AND CLARKE

32. Those who imagine that souls can give a new force to
bodies, and that God does the same in the world so as to
correct the imperfections of His machine, make God too like
the soul, by attributing too much to the soul and too little
to God.

33. For it is only God that can give nature new forces, and
He does it supernaturally only. If He needed to do it in the
natural course of things He would have made a very im-
perfect work. He would be, in the world, like what the
soul is commonly held to be in the body.

38. Those who imagine that active forces 1 diminish of
themselves in the world, do not properly understand the
principal laws of nature, and the beauty of the works of
God.

41. The author says that space does not depend on the
situation of bodies. I answer that it is true that it does not
depend on such and such a particular situation of bodies; but
it is the order which makes bodies capable of having situation,
and through which they have a situation with regard to one
another when existing together; just as time is this order in
relation to their successive position. But if there were no
created beings space and time would only exist in the ideas
of God. 2

1 Clarke says that when he spoke of active forces diminishing,
he meant by active force ' nothing but motion, and the impetus
or relative impulsive force of bodies, arising from and being
proportional to their motion '. He quotes from Newton's Optics :
' Since therefore all the various motions that are in the world are
perpetually decreasing, 'tis absolutely necessary, in order to
preserve and renew those motions, that we have recourse to some
active principles 1 . (The translation from Newton's Latin is
by Clarke.)

* Several sections containing a further discussion of the nature
of miracles are omitted here.

LEIBNIZ AND CLARKE 209

P.S.

All those who believe in the void allow themselves to be
guided more by imagination than by reason. When I was
a young man, I also was inclined to believe in the void and
in atoms; but reason brought me back. Imagination was
utterly contented. On this theory a limit is set to our
researches; reflection is fixed and as it were pinned down;
we suppose ourselves to have found the first elements a non
plus ultra. We should like nature to go no further;
we should like it to be finite, like our mind; but this is
to ignore the greatness and majesty of the Author of
things. Actually the least corpuscle is subdivided ad
infinitum and contains a world of new created things, which
the universe would lack if this corpuscle were an atom, that
is a body all of a piece and not subdivided. All the same, to
want to put a void in nature is to attribute to God a very
imperfect production; it is to violate the great principle of
the necessity of a sufficient reason, of which many people
speak with their lips without at all recognizing its force, as I
showed recently when I made it clear by means of this
principle that space is only an order of things, like time, and
in no sense an absolute being. Not to mention many other
reasons against the void and atoms, here are those which I
derive from the perfection of God and from sufficient reason.
I assume that any perfection which God could put in things
without derogating from the other perfections in them, has
been put there. Now let us imagine a space entirely empty;
God could put in it some matter without in any way dero-
gating from anything else whatever; therefore He did put
some matter therein; therefore there is no space entirely
empty; therefore everything is full. The same argument
proves that there is no corpuscle which is not subdivided.
Here also is the reason taken from the necessity of a
sufficient reason. It is not possible that there should be a

210 LEIBNIZ AND CLARKE

principle determining the proportion of matter, or what is
filled, to the void, or of the void to the plenum. It will
perhaps be said that one must be equal to the other; but as
matter has more perfection than empty space, reason demands
that geometrical proportion be observed, and that there
should be more plenum in proportion as it is worthy of
preference. But then there would be no void at all, for the
perfection of matter is to the perfection of the void as some-
thing is to nothing. The same argument applies to atoms.
What reason can be assigned for limiting nature in the process
of subdivision? Purely arbitrary fictions, and unworthy of
true philosophy. The reasons alleged in favour of the void
are but sophisms.

LEIBNIZ'S FIFTH PAPER 1

8. 8 But the good, whether true or apparent, in a word the
motive, inclines without necessitating, that is to say without
imposing an absolute necessity. For when God (for instance)
chooses the best, that which He does not choose and which is
inferior in perfection is none the less possible. If what God
chooses were necessary, everything else would be impossible,
which would be contrary to our hypothesis, for God chooses
between possibles, that is to say between several things, not
one of which implies a contradiction.

9. To say that God can only choose the best, and to infer
from this that what He does not choose is impossible, is to
confuse terms: namely, power and will, metaphysical neces-
sity and moral necessity, essences and existences. For what
is necessary is so by its essence, because the opposite implies
a contradiction; but the contingent which exists owes its
existence to the principle of what is best, the sufficient

1 Written in answer to Clarke's reply to the Fourth Paper.
Here Leibniz takes up the points at much greater length. It
will be seen that much of this paper has been omitted here.

1 1-7 contain further answers to the charge of fatalism. Cf.
p. 197-

LEIBNIZ AND CLARKE 211

reason for things. And this is why I say that motives incline
without necessitating; and that there is a certainty and
infallibility, but not an absolute necessity, in contingent
things.

10. And I have sufficiently shown in my Theodicy that
this moral necessity is good, and in conformity with Divine
perfection, and in conformity with the great principle of
existences, which is that of the need of a sufficient reason;
whereas absolute metaphysical necessity depends on the
other great principle of our reasonings, the principle of
essences, that is to say that of identity or contradiction: for
what is absolutely necessary is the only possible course, and
its contrary implies a contradiction.

11, I have shown also that our will does not always
precisely follow the practical understanding, because it may
have or find reasons for suspending its resolution until a
further discussion.

14. ... I now come to the objection made against my
comparison between the weights of a balance and the motives
of the will. The author objects that the balance is purely pas-
sive and weighed down by the weights, whereas agents which
are intelligent and endowed with will are active. To this I
reply, that the principle of the necessity of a sufficient reason
is common both to active and to passive things. They need
a sufficient reason for their activity as well as for their
passivity. Not only does the balance not act when it is
weighed down equally on both sides, but equal weights do
not act either, when they are in equilibrium in such a way
that one cannot go down without the other going up to the
same extent.

15. It must also be considered that, strictly speaking,
motives do not act on the mind like weights on a balance; it is
rather the mind which acts by virtue of the motives, which
are its dispositions to act. Thus to maintain, as it is here

212 LEIBNIZ AND CLARKE

maintained, that the mind sometimes prefers weak motives
above stronger ones, and even sometimes what is indifferent
above motives, is to separate the mind from its motives, as
if they were outside of it, as the weight is distinct from the
balance; and as if there were in the mind other dispositions
to action besides motives, by virtue of which the mind
rejected or accepted the motives. Whereas the truth is that
motives comprise all the dispositions which the mind can
have to act voluntarily, for they comprise not only reasons
but also inclinations, which come from the passions or from
other preceding impressions. Thus if the mind preferred a
weak above a strong inclination it would be acting against
itself and otherwise than it is disposed to act. This shows
that notions which differ on this point from mine are super-
ficial and turn out to have nothing in them, when they are
properly considered.

1 6. To say also that the mind may have good reasons for
acting when it has no motives, and when things are absolutely
indifferent, as is explained here, is a manifest contradiction.
For if there are good reasons for the course it adopts, the
things are not indifferent to it.

17. And to say that a man will act when he has reasons for
acting, even though the ways of acting may be absolutely in-
different, is again to speak most superficially, and in a very
unjustifiable manner. For in this case there is no sufficient
reason for acting when there is not a sufficient reason for
acting in a particular manner, since every action is individual,
and not general or abstracted from its circumstances, and
it needs some way of being carried out. Thus when there is
a sufficient reason for doing a particular action, there is a
sufficient reason also for acting in a particular way, and
consequently the ways of acting are not indifferent. On
every occasion that a man has sufficient reasons for a given
particular action, he has sufficient reasons also for doing
everything which is requisite for that action.

LEIBNIZ AND CLARKE 213

21. It must be admitted that this great principle, 1 although
it has been recognized, has not been sufficiently made use of.
And this is to a great extent why First Philosophy 2 has been
so little productive and demonstrative hitherto. I infer from
this principle, among other consequences, that there are not
in nature two real absolute beings which are indiscernible
from one another; because if there were, God and nature
would be acting without reason in treating one differently
from the other; and thus that God does not produce two
portions of matter which are perfectly equal and alike. The
author replies to this conclusion without refuting the reason
for it, and he replies by a very feeble objection. That
argument, he says, if it was good would prove that it would be
impossible for God to create any matter at all. For the perfectly
solid parts of matter, if we take them of equal figure and di-
mensions (which is always possible in supposition) would be
exactly alike. But it is an obvious petitio principii to suppose
this perfect agreement which, on my view, cannot be ad-
mitted. This supposition of two indiscernibles, as of two
portions of matter which perfectly agree with one another,
seems possible in the abstract, but it is not compatible with
the order of things, nor with Divine wisdom, by which
nothing is admitted without a reason. The vulgar imagine
such things because they are satisfied with incomplete notions.
And this is one of the faults of the Atomists.

22. Besides, I do not allow that there are in matter parts
which are perfectly solid, or which are all of a piece, without
any variety or particular motion in their parts, as the pre-
tended atoms are conceived to be. To suppose that there
are such bodies is another popular and ill-founded opinion.
According to my demonstrations, each portion of matter is
actually subdivided into parts differently affected, and no
one altogether resembles another.

1 i.e. the principle of sufficient reason,
"i.e. metaphysics.

214 LEIBNIZ AND CLARKE

23. I had maintained that two indiscernibles can never be
found among sensible things, and that, for example, we should
never find two leaves in a garden, nor two drops of water,
which were perfectly alike. The author admits this with
regard to leaves and 'perhaps* with regard to drops of water.
But it might be admitted without question, or without the
'perhaps', of the drops of water too.

24. I hold that these general observations which apply to
sensible things apply also in proportion to insensible things.
And that in this respect it may be said, as Harlequin says in
the Emperor of the Moon, ' 'tis there as 'tis here'. And it is a
great argument against indiscernibles that no instance of
them can be found. But the author objects to this conse-
quence on the ground that sensible bodies are compounded,
whereas there are alleged to be insensible bodies which are
simple. I answer again that I do not admit of any. Accord-
ing to me, there is nothing simple except true monads, which
have no parts and no extension. Simple bodies and even
perfectly similar ones are a consequence of the false doctrine
of a void and of atoms, or else of lazy philosophy, which does
not press far enough the analysis of things, and thinks it can
arrive at the primary corporeal elements of nature, since they
would satisfy our imagination.

25. When I deny that there are two drops of water perfectly
alike, or two other bodies indiscernible from one another, I
do not mean that it is absolutely impossible to suppose them,
but that it is a thing contrary to Divine wisdom and conse-
quently that it does not exist.

26. I admit that if two perfectly indiscernible things did
exist, they would be two. But the supposition is false,
and contrary to the great principle of reason. The vulgar
philosophers were mistaken when they thought that there
existed things which differed solo numero, 1 or only because
they were tivo: and it is from this error that their perplexities

1 'numerically only*.

LEIBNIZ AND CLARKE 215

about what they called the principle of individuation arose.
Metaphysics has ordinarily been treated as a mere doctrine
of terms, like a philosophical dictionary, without ever coming
to a discussion of things. Superficial philosophy , like that of
the Atomists and Vacuists, fabricates for itself things which
higher reasons render inadmissible. I hope that my proofs
will change the face of philosophy, in spite of feeble contra-
dictions such as I meet with here.

27. The parts of time and of place, taken in themselves,
are ideal things: thus they are perfectly alike, like two
abstract units. But this is not the case with two concrete
unities, nor with two actual times, nor with two occupied,
that is to say truly actual, spaces.

28. I do not say that two points of space are one and the
same point, nor that two instants of time are one and the
same instant, as seems to be imputed to me. But it may be
imagined through lack of knowledge that there are two
different instants when there is one only, as I observed in
17 of my foregoing reply that often in geometry we suppose
there to be two, so as to show up an opponent's error, and
find but one. If someone supposed that one straight line
cut another at two points he would ultimately find out that
these two pretended points must coincide and can only make
one. This also happens when a straight line, which in all
other instances cuts a given curve, becomes a tangent.

29. I have proved that space is nothing other than an
order of the existence of things, which is observed when they
exist simultaneously. Thus the fiction of a finite material
universe, the whole of which moves about in an infinite empty
space, cannot be admitted. It is altogether unreasonable
and impracticable. For besides the fact that there is no
real space outside the material universe, such an action
would be without purpose; it would be working without doing
anything, agenda nihil agere. No change which could be
observed by any one whatever would be occurring. Such

216 LEIBNIZ AND CLARKE

things are the imaginings of philosophers with incomplete
notions, who make of space an absolute reality. Mere
mathematicians who do but concern themselves with the
play of the imagination are capable of fabricating to them-
selves such notions; but they are destroyed by higher reasons.

30. Absolutely speaking, it appears that God is able to
make the material universe finite in extension; but the
contrary seems better to conform with His wisdom.

31. I do not allow that everything finite is mobile. Indeed,
according to the hypothesis of my opponents, a part of space,
though finite, is not mobile. What is mobile must be able to
change its position in relation to something else, and it must
be possible for a new state discernible from the first state
to arise: otherwise the change is a fiction. Thus a mobile
finite thing must be part of some other finite thing, so that a
change that can be observed can take place.

32. Descartes maintained that matter has no limits, and I
do not think he has been sufficiently refuted. And even if
this is granted him, 1 it does not follow that matter would be
necessary, nor that it should have existed from all eternity,
since the unlimited diffusion of matter would but be an effect
of the choice of God, who held it to be better so.

33. Since space is itself a thing ideal, like time, space
outside the world must certainly be imaginary, as the
Schoolmen themselves recognized well enough. The same
is true of empty space in the world, which I also hold to be
imaginary for the reasons I have given.

34. The author brings forward as an objection against me
the vacuum discovered by M. Guericke of Magdeburg: this
was made by pumping the air out of a container. It is
claimed that there genuinely is a perfect void, or space empty

1 Clarke had said : ' To say that God could not have altered the
time or place of the existence of matter, is making it to be
necessarily infinite and eternal, and reducing all things to Necessity
and Fate '.

LEIBNIZ AND CLARKE 217

of matter, in part at least, in the container. The Aristote-
lians and the Cartesians, who do not admit the existence of a
true void, replied to this experiment of M. Guericke's as well
as to the experiment made by M. Torricelli of Florence (who
emptied the air out of a glass tube by means of mercury), by
saying that there is no vacuum at all in the tube or in the
container since the glass has subtle pores, through which
rays of light, magnetic rays, and other very fine things can
pass. And I am of their opinion. For I hold that the con-
tainer may be compared to a box full of holes placed in
water, in which there are fish or other gross bodies, which
being removed, their room would not fail to be filled with
water. There is this difference only, that water, though it is
fluid and more amenable than these gross bodies, is yet as
heavy and as massive as they are, or even more so; whereas
the matter which enters the container in the room of the air
is much finer. The new supporters of the void reply in this
instance that it is not the grossness of matter, but simply its
quantity, which produces resistance, and that consequently
there is necessarily more void where there is less resistance.
They add that subtlety has nothing to do with it, and that
the parts of quicksilver are as subtle and as fine as those of
water, and that yet quicksilver has more than ten times the
resistance. To this I answer, that it is not so much the
quantity of matter as the difficulties it makes in giving way
which causes the resistance. For example, floating timber
contains less weight of matter than water of equal volume,
and yet it resists a boat more than the water does.

35. And as to quicksilver, it contains in truth about
fourteen times as much weight of matter as an equal volume
of water; but it does not follow that it contains fourteen times
more matter absolutely. On the contrary, water contains as
much, if we take together both its own matter which has
weight and a foreign matter of no weight which passes through
its pores. For both quicksilver and water are masses of heavy

218 LEIBNIZ AND CLARKE

matter pierced with holes, through which there passes a great
deal of matter which has no weight and which does not resist
sensibly. Such, it appears, is the matter which composes
rays of light, and other insensible fluids ; such above all is that
fluid which itself causes the weight or gravity of gross bodies,
by withdrawing itself from the centre where it forces them
to go. For it is a strange fiction to regard all matter as having
weight or gravity, and even to regard it as gravitating
towards all other matter, as if every body had an equal
attraction for every other body in proportion to mass and
distance ; and this, by means of attraction properly so called,
and not derived from an occult impulsion of the bodies.
Whereas in truth the gravitation of sensible bodies towards
the centre of the earth must be produced by the movement
of some fluid. And the same is true of other gravitations
such as those of the planets towards the sun or towards one
another. A body is never moved naturally except by
another body which impels it by touching it; and after this
it goes on until it is hindered by another body touching it.
Any other operation on bodies is either miraculous or
imaginary.

36. As I objected that space, taken as something real and
absolute without bodies, would be a thing eternal, impassive,
and independent of God, our author has tried to elude this
difficulty by saying that space is a property of God. In my
previous paper I opposed this by saying that the property of
God is immensity; but that space, which is often commen-
surate with bodies, and the immensity of God are not the
same thing.

37. I further objected that if space is a property, and if
infinite space is the immensity of God, then finite space will
be the extension or mensurability of something finite. Thus
the space occupied by a body will be the extension of that
body: an absurd thing, since a body can change space, but
cannot leave its extension.

LEIBNIZ AND CLARKE 219

38. I also asked: If space is a property, of what thing will
a limited empty space, such as is imagined in the container
emptied of air, be the property? It does not seem reasonable
to say that this round or square empty space is a property
of God. Is it perhaps the property of some immaterial,
extended, imaginary substance which (it seems) our author
pictures to himself in the imaginary spaces ?

39. If space is the property or affection of the substance
which is in space, the same space would be the affection now
of one body, now of another body, now of an immaterial
substance, now perhaps of God, when it is empty of any other
substance, material or immaterial. But it must be a very
strange property or affection to pass like this from subject to
subject. Subjects would thus put off their accidents like
garments, so that other subjects could put them on. After
that, how would one distinguish accidents and substances?

40. If limited spaces are the affections of limited substances
which are in them, and if infinite space is the property of God,
it must follow (strange though it may seem) that the property
of God is composed of the affections of created things ; for all
the finite spaces, taken together, make up infinite space.

41. If it is denied that limited space is an affection of
limited things, it will not be reasonable either for infinite
space to be the affection or property of an infinite thing. I
have touched on all these difficulties in my previous paper,
but it does not look as though any attempt has been made to
answer them.

42. I have yet other reasons against this strange fancy that
space is a property of God. If it is, space enters into the
essence of God. Now space has parts, so there would be
parts in the essence of God. Spectatum admtsst. 1

43. Moreover, spaces are sometimes empty, sometimes
full: thus there would be in the essence of God parts which

1 Spectatum admissi risum teneatis, amid ? * If you saw such a
thing, my friends, could you restrain your laughter? '

220 LEIBNIZ AND CLARKE

are sometimes empty, sometimes full, and consequently
subject to a perpetual change. The bodies which fill space
would fill a part of the essence of God, and would be com-
mensurate with it; and, on the supposition of a vacuum, a
part of the essence of God would be in the container. This
God with parts will be very like the Stoic God, who was the
whole universe, considered as a divine animal.

44. If infinite space is God's immensity, infinite time will
be God's eternity. We must say, then, that what is in space
is in God's immensity, and consequently in His essence; and
that what is in time is in the essence of God also. Strange
phrases, which plainly show that our author is misusing terms.

45. Here is another instance: God's immensity makes
Him present in all spaces. But if God is in space, how can
it be said that space is in God, or that it is His property? We
have heard of the property being in the subject, but never
of the subject being in its property. In the same way God
exists in every time; how then is time in God, and how can
it be a property of God ? These are perpetual dAAoyAcorrtou. 1

46. It looks as though the immensity or extension of things
were being confused with the space according to which that
extension is taken. Infinite space is not the immensity of
God, finite space is not the extension of bodies, just as time
is not their duration. Things keep their extension, but they
do not always keep their space. Each thing has its own
extension, its own duration; but it does not have its own
time, and it does not keep its own space.

47. This is how men come to form the notion of space.
They consider that several things exist at the same time, and
they find in them a certain order of co-existence, in accordance
with which the relation of one thing to another is more or
less simple. This is their situation or distance. When it
happens that one of these co-existent things changes its
relation to a number of others without their changing with

1 'misuses of words'.

LEIBNIZ AND CLARKE 221

regard to one another, and when another thing makes its
appearance and acquires the same relation to the others as
the first one had, we say that it has taken its place, and we
call this change a motion in that body wherein is the im-
mediate cause of the change. And when several or even all
of these co-existent things change in accordance with certain
known rules of direction and velocity, we can always deter-
mine the relation of situation which any given body acquires
with regard to every other: and even the relation which any
other would have, or which the given body would have to
any other, if it had not changed, or if it had changed in a
different way. If we suppose or pretend that among these
co-existents there were a sufficient number which suffered
no change in themselves, we should say that those which
have the same relation to these fixed existents as others had
before, occupy the same place as those others occupied. That
which includes all these places is called space. This shows
that in order to have the idea of place, and consequently of
space, it is enough to consider these relations and the rules
of their changes, without needing to picture any absolute
reality beyond the things whose situation is being considered.
To give a kind of definition : Place is that which is said to be
the same for A and for B, when the relation of co-existence
between B and C, E, F, G, etc., entirely agrees with the
relation of co-existence which A previously had with those
bodies, supposing there has been no cause of change in
C, E, F, G, etc. It may also be said (without K0ais l ) that
place is that which is the same at different moments for certain
entities when they, although different, have relations of co-
existence with other entities (these latter being supposed to
be fixed from the one of these moments to the other) which
agree entirely. And fixed entities are those in which there
has been no cause for a change of the order of co-existence
with others, or (which is the same thing) in which there has
1 i.e. without particular enunciation.

222 LEIBNIZ AND CLARKE

been no motion. Lastly, space is that which results from
places taken together. And it is well here to consider the
difference between the place and the relation of situation of
the body which occupies the place. For the place of A and
B is the same, whereas the relation of A to the fixed bodies
is not precisely and individually the same as the relation
that B (which is to take its place) will have to the same
fixed bodies; these relations only agree. For two different
subjects, such as A and B, cannot have exactly the same
individual affection, since one and the same individual
accident cannot occur in two subjects, nor pass from one
subject to another. But the mind, not content with agree-
ment, seeks an identity, a thing which is truly the same, and
conceives it as outside these subjects; and this is what is
here called place and space. This, however, can only be ideal,
comprising a certain order wherein the mind conceives the
application of the relations: just as the mind can imagine an
order consisting of genealogical lines, whose length would
consist only in the number of generations, in which each
person would have his place. And if we added the fiction of
metempsychosis, and made the same human souls come in
again, the persons might change their places in these lines,
He who had been father or grandfather might become son or
grandson, etc. And yet those genealogical places, lines, and
spaces, although they expressed real truths, would only be
ideal things. I will give another example of the mind's
habit of creating for itself, upon occasion of accidents
existing in subjects, something which corresponds to those
accidents outside the subjects. The ratio or proportion of
two lines L and M can be conceived in three ways : as a ratio
of the greater L to the smaller M, as a ratio of the smaller M to
the greater L, and lastly as something abstracted from both
of them, that is to say as the ratio between L and M , without
considering which is the anterior and which the posterior,
which the subject and which the object. It is in this way

LEIBNIZ AND CLARKE 223

that proportions are considered in music. In the first way
of considering them, L the greater is the subject ; in the second,
M the smaller is the subject of this accident which philosophers
call relation. But which will be the subject in the third way
of considering them ? We cannot say that the two, L and M
together, are the subject of such an accident, for in that case
we should have an accident in two subjects, with one leg in
one and the other leg in the other, which is contrary to the
notion of accidents. Thus we are bound to say that the
relation in this third way of considering it is indeed outside
the subjects; but that being neither substance nor accident,
it must be a purely ideal thing, the consideration of which is
none the less useful. For the rest, I have acted rather like
Euclid, who, when he could not make it absolutely under-
stood what is meant by ratio, in the geometricians' sense,
defined properly what is meant by the same ratios. In the
same way, in order to explain what place is, I have tried to
define the same place. Finally I remark that the traces
which mobile things sometimes leave on the immobile things
on which they exercise their motion, have afforded to men's
imagination occasion to form this idea, as if there still
remained some trace even when there is nothing immobile:
but this is ideal merely, and only means that if there were
something immobile actually there, the trace might be pointed out
on it. And it is this analogy which causes us to imagine
places, traces, and spaces, although these things only consist
in the truth of relations, and nowise in any absolute reality.

49. We cannot say that a certain duration is eternal, but
we can say that the things which last for ever are eternal,
because they are always acquiring a new duration. What-
ever of time and of duration does exist, since it is successive,
continually perishes. And how could a thing exist eternally
which properly speaking never exists? And how could a
thing exist, no part of which ever exists? In the case of time
R95

224 LEIBNIZ AND CLARKE

nothing exists but instants, and an instant is not even a
part of time. Whoever gives proper consideration to these
observations will easily understand that time can only be an
ideal thing. And the analogy of time and space will indeed
make us judge that the one is as ideal as the other. Still, if,
when it is said that the duration of a thing is eternal, this
only means that the thing endures eternally, I have nothing
further to say.

52. In order to prove that space without bodies is an
absolute reality, the author raised it as an objection to my
view that a finite material universe might move about in
space. I answered, that it does not seem reasonable that the
material universe should be finite; and even if it were supposed
to be so, it is unreasonable that it should have any movement
except in so far as its parts change their situation among
themselves : because a movement of this kind would produce
no observable change and would be without purpose. It is a
different thing when its parts change their situation among
themselves, for then we recognize a movement in space; but
it consists in the order of the relations, which are changed.
The author now answers that the truth of the movement is
independent of its being observed, and that a ship can go
forward without a man who is in it perceiving the motion.
I answer that motion is independent of being observed, but it
is not independent of being observable. There is no motion
when there is no observable change. Moreover, when there is
no observable change, there is no change at all. The contrary
view is based on the supposition of a real absolute space,
which I demonstratively refuted by the principle of the
necessity of a sufficient reason of things.

53. I find nothing in the eighth definition of the Mathe-
matical Principles of Nature, nor in the Scholium of this
definition, which proves, or can prove the reality of space in
itself. But I grant that there is a difference between a

LEIBNIZ AND CLARKE 225

genuine absolute movement of a body and a simple relative
change of its situation with respect to another body. For
when the immediate cause of the change is in the body, it is
genuinely in motion and then the situation of the rest with
respect to it will be changed in consequence, although the
cause of this change is not in them. It is true that, to speak
exactly, there is no body which is perfectly and entirely at
rest; it is an abstraction which we make when we consider
the thing mathematically. Thus I have left unanswered
nothing of all the arguments alleged in favour of the absolute
reality of space. And I have proved the falsity of this
reality by one of the most reasonable and well founded of
fundamental principles, against which no exception nor
example can be brought. For the rest, it may be seen from
all that I have just said, that I cannot admit a movable
universe, nor any place outside the material universe.

54. I know of no objection which I do not think I have
adequately answered. And as to this objection that space
and time are quantities, or rather things having quantity,
and that situation and order are not such, I reply that order
also has its quantity: there is that which precedes and that
which follows, there is distance or interval. Relative things
have their quantity as well as absolutes: for example, ratios
or proportions in mathematics have their quantity and are
measured by logarithms, and yet they are relations. Thus
although time and space consist in relations, they have their
quantity none the less.

57. This enables us to see how to interpret the truth that
God created things at the time which was pleasing to Him,
for the time depends on the things which He resolves to
create. Once the things have been resolved upon with their
relations, there remains no further choice of time or place;
for these considered apart have nothing real in them, nothing
to determine them, and indeed nothing that is discernible.

226 LEIBNIZ AND CLARKE

58. So it cannot be said, as is said here, that the wisdom of
God may have good reasons for creating this world at a given
particular time; for this particular time, taken apart from
things, is an impossible fiction, and there can be no good
reasons for a choice there where everything is indiscernible.

60. It should not then be said, as is said here, that God
created things in a particular space, or at a particular time,
which was pleasing to Him, for since all times and all spaces
are in themselves perfectly uniform and indiscernible, one
cannot please more than another.

63. But it nowise follows that matter is eternal and neces-
sary, unless we suppose that space is eternal and necessary:
an altogether ill-founded supposition.

67. The parts of space are determined and distinguished
only by the things which are in them, and the diversity of the
things in space determines God to act differently on different
parts of space. But space, taken apart from things, has
nothing in itself to determine it, and indeed it has nothing
actual about it.

68. If God has decided to place a certain cube of matter,
He thereby also becomes determined on the place of the cube:
but this is with respect to other particles of matter, and not
with respect to detached space which has nothing in it to
distinguish it.

93. I do not admit that every action gives a new force
to the thing acted upon. It often happens at the meeting of
bodies that each keeps its force, as when two hard bodies of
equal size meet directly. Then the direction alone is changed,
without there being any change in the force, each body taking
the direction of the other, and turning back with the same
velocity it had before.

LEIBNIZ AND CLARKE 227

94. I am, however, careful not to say that it is supernatural
to give a body a new force, for I recognize that one body often
receives a new force from another body, which loses as much
of its own. But I say merely that it is supernatural for the
whole universe of bodies to receive a new force; and thus that
one body should gain force without others losing the same
amount. This is why I say also that it cannot be maintained
that the soul gives force to the body; for then the whole
universe of bodies would receive a new force.

99. I do not here undertake to establish my Dynamics, or
my doctrine of forces. This would not be the proper place.
But I can reply very well to the objection raised here. I had
maintained that active forces are preserved in the world.
The objection is that two soft non-elastic bodies meeting to-
gether lose their force. I answer that this is not so. It is true
that the wholes lose it in relation to their total movement,
but the parts receive it, being internally agitated by the
force of the meeting or shock. Thus this loss occurs in
appearance only. The forces are not destroyed, but dissi-
pated among the small parts. There is here no loss of forces,
but the same thing happens as takes place when big money
is turned into small change. I agree, however, that the
quantity of motion does not remain the same, and in this
matter I approve what is said on page 341 of Mr. Newton's
Optics which the author here quotes. But I have shown
elsewhere that there is a difference between the quantity of
motion and the quantity of force.

104. I do not say that space is an order or situation which
makes things situable. That would be talking nonsense. It
is only necessary to consider my own words and to join them
with what I have said above ( 47), to show how the mind
comes to form the idea of space, without its being necessary
for there to be a real and absolute being, corresponding to

228 LEIBNIZ AND CLARKE

that idea, outside of the mind and outside of relations. I
do not say then that space is an order or situation, but an
order of situations, or an order according to which situations
are arranged ; and that abstract space is this order of situations
which are conceived as possible. Thus it is something ideal,
but the author appears not to want to understand me. I
have already replied ( 54) to the objection that an order is
not capable of quantity.

105. The author objects that time could not be an order of
successive things, because the quantity of time can become
greater or smaller, while the order of successions remains the
same. I answer that this is not so ; for if the time is greater
there will be more similar successive states interposed, and if
it is less there will be fewer, because there is no void nor
condensation nor penetration (so to speak) in times any more
than in places.

106. I maintain that if there were no created things, the
immensity and eternity of God would none the less subsist,
but without any dependence on times or places. If there
were no created things there would be no time or place, and
consequently no actual space. The immensity of God is
independent of space, as the eternity of God is independent
of time. They only signify with regard to these two orders
of things that God would be present and co-existent with
everything which existed. Thus I do not admit what is
here advanced, that if God alone existed time and space
would exist as at present. On the contrary, on my view,
they would exist in ideas only, like mere possibilities. The
immensity and eternity of God are something more eminent
than the duration and extension of created beings, not only in
relation to the greatness, but also to the nature of the thing.
These Divine attributes are not dependent upon things
outside God, as are actual places and times. These truths
have been sufficiently recognized by theologians and
philosophers.

LEIBNIZ AND CLARKE 229

124. The natural forces of bodies are all subject to
mechanical laws; and the natural forces of minds are all
subject to moral laws. The former follow the order of
efficient causes; and the latter follow the order of final causes.
The former operate without liberty, like a watch; the latter
are exercised with liberty, although they agree exactly with
that kind of watch which another, superior, free cause has
set beforehand to fit in with them. I have already spoken
of this in the present paper ( 92).

PART III

MISCELLANEOUS EXTRACTS FROM
LEIBNIZ'S PHILOSOPHICAL WRITINGS

From a letter to Landgraf Ernst von Hessen Rheinfels
November 1686

I TAKE the liberty, Sire, once more to entreat Your Serene
Highness to be good enough to have the enclosed papers
given to M. Arnauld, and since they treat of matters removed
from the outer senses and dependent on pure intellection,
matters which are not pleasing to, and are most often despised
by, those who are most alive and most excellent in the
affairs of the world, I will here say something in favour of
these meditations. It is not that I am so ridiculous as to
desire that Your Serene Highness should amuse himself
therewith (this would be as unreasonable as to want the general
of an army to apply himself to algebra, although this science
is very useful for anything which has any connection with
mathematics). My aim is rather that Your Serene Highness
may better be able to form a judgment of the purpose and
value of such reflections, which might seem but little worthy
to occupy, even for a moment, a man to whom all moments
must be precious. In truth, in the way in which these things
are ordinarily treated by the Scholastics, they are but disputes,
distinctions, a play upon words. Yet there are veins of gold
among these barren rocks. I take it to be a fact that thought
is the principal and perpetual function of our soul. We
shall always think, but we shall not always live here. This
is why whatever renders us more capable of reflecting on
more perfect objects and in a more perfect manner, also
makes us naturally perfect. But the present condition of
our life forces us to have a great number of confused thoughts
which do not make us more perfect. Such is the knowledge
of customs, genealogies, and languages, and indeed all
historical knowledge of facts both civil and natural. This is

233

234 MISCELLANEOUS EXTRACTS

useful to us for avoiding dangers and for handling the bodies
and men around us, but it does not enlighten the mind. The
knowledge of routes is useful to a traveller on his journey;
but that knowledge which has more relation to the functions
to which he is destined in patria l is more important to him.
Now we are destined one day to live a spiritual life, where
substances separated from matter will occupy us much more
than bodies. But in order to distinguish better between
knowledge that enlightens the mind and that which merely
leads it blindfold, consider these examples taken from the
arts. If a workman knows, by experience or from tradition,
that if the diameter is 7 feet the circumference of the circle
is a little less than 22 feet; or if a gunner knows by hearsay,
or because he has frequently measured it, that bodies carry
furthest when thrown at an angle of 45 degrees, theirs is a
confused knowledge, the knowledge of an artisan who will
make very good use of it to earn his living and in the service
of others. But the knowledge which enlightens our mind, is
that which is distinct, that is to say, which contains the causes
or reasons, as when Archimedes gave the proof of the first
law, and Galileo that of the second. In a word, the only
knowledge which can make us perfect is the knowledge of
reasons in themselves, or of eternal and necessary truths,
especially those truths which are most comprehensive and
which bear most relation to the Sovereign Being. This
knowledge alone is good in itself; all the rest is mercenary,
and we should only learn it through necessity, by reason of
the needs of this life, and so that we may be the better able
to make room afterwards for the perfection of the mind,
when we have put in order all that which concerns our
subsistence. Yet the disorderliness of mankind, and what is
called the care de pane lucrando? and often vanity also,

x * in his fatherland', i.e. when he is at home in his own
country, and not travelling.
* ' of earning daily bread'.

MISCELLANEOUS EXTRACTS 235

causes us to forget the master for the valet and the end for
the means. This, as the poet says, is exactly propter vitam
vivendi perdere causas. 1 It is very much like a miser pre-
ferring gold to health, whereas gold exists but to serve the
conveniences of living. Now since what perfects our mind
(if we leave on one side the illumination of grace) is the
demonstrative knowledge of the greatest truths by their
causes or reasons, it must be admitted that metaphysics or
natural theology, which treats of immaterial substances, and
particularly of God and the soul, is the most important of all.
And it is impossible to make progress in this without knowing
the genuine notion of substance, which I explained in such a
way in my last letter to M. Arnauld that he himself, who is
so exact, and who had been shocked by it at the outset, gave
to it his acceptance.

Finally, these meditations provide us with conclusions
which are surprising but of marvellous utility for delivering
us from the greatest scruples regarding God's care for His
creatures, His prescience and preordination, the union of
soul and body, the origin of evil, and other things of this kind.
I will not here say anything of the great value of these
principles in the human sciences; but at least I can say that
nothing is more instrumental in raising our mind to the
knowledge and love of God, so far as nature helps us. I
admit that all this is of no use without grace, and that God
gives grace to some people who have never dreamt of these
meditations. But God desires also that we should omit
nothing on our side, and that we should use the perfections
which He has given to human nature, as opportunity offers,
each of us according to his vocation; as His sole purpose in
making us was that we should know and love Him, we
cannot work for it too much, nor make a better use of our
time and energies, unless we are otherwise engaged for the
public and for the welfare of others.

1 ' for the sake of life to lose the causes of living*.

236 MISCELLANEOUS EXTRACTS

From the Discourse of Metaphysic. 1686

. . . Suppose, for example, that someone marks a number of
points on a sheet of paper entirely at random, in the manner
of those who practise the ridiculous art of geomancy. I say
that it is possible to find a geometrical line whose motion is
constant and uniform in accordance with a certain rule, such
that this line shall pass through all the points, and in the same
order in which they were marked by the pen. . . . Nor is there
any instance of a face whose contour does not form part of a
geometrical line, and which cannot be traced at one stroke
by a given regulated movement. But when a rule is very
complicated, that which conforms to it passes for being
irregular. . . .

From the same work

The ancient philosophers had very little knowledge of
these important truths. Jesus Christ alone has expressed
them divinely well, and in a manner so clear and so familiar
that the dullest minds have been able to understand them:
that is why His Gospel has completely changed the face of
human affairs. He has made known to us the Kingdom of
Heaven or that perfect commonwealth of minds which
deserves to be called the City of God, whose admirable laws
He has revealed to us. He alone has made us see the extent
of God's love for us, and with what accuracy He has provided
for all that concerns us. He has shown us that He who
cares for the sparrows will not neglect the rational creatures
who are infinitely dearer to Him; that all the hairs of our
head are numbered; that heaven and earth shall pass
away rather than that the word of God, and all that belongs
to the economy of our salvation, shall be changed ; that God
has more care for the least among intelligent souls than for
the whole machine of the world; that we ought not to fear

MISCELLANEOUS EXTRACTS 237

those who have power to destroy the body, but cannot hurt
the soul, which God alone can make happy or miserable;
and that the souls of the just are in His hand, safe from all the
revolutions of the universe, since nothing can act upon them
save God alone; that not one of our actions is forgotten, but
everything is included in the final reckoning, even idle words
and the least spoonful of water that has been put to a good
use; finally that everything must work for the greatest good
of the righteous; that the just will be like suns, and that
neither our senses nor our minds have ever tasted anything
approaching the happiness which God prepares for those
who love Him.

From a paper without superscription precepts for advancing
the sciences. (Date unknown)

The human race, considered in relation to the sciences
which minister to our happiness, appears to me like a
disorderly rabble marching in the darkness, having neither
leader nor order, without password or other signals to
regulate their march, or by which to know themselves.
Instead of holding one another by the hand so as to guide
one another and make sure of our way, we run about at
random and to and fro, and even hurl ourselves one against
another, far from helping and supporting each other. This
means that we advance but little, or else that we know not
where we are. We even plunge into morasses and shifting
sands of doubts without end, wherein is nothing solid nor
firm, or else we drag ourselves into the principles of very
dangerous errors. Talibus in tenebris vitae tantisque peridisf
it is given to no mortal to light a torch capable of dispersing
this obscurity. Sects and leaders of sects serve merely to
seduce us like the false lights of marsh fires; and it is left
to the sun of our souls to enlighten us utterly, but in another
1 ' In such darkness of life and in so great dangers'.

238 MISCELLANEOUS EXTRACTS

life. Nevertheless, what we can do here is to march together
and in order, to share our journeyings, to make known the
roads and to repair them: and finally to travel slowly, but
with a firm unwavering tread, by the side of that pure and
living stream of clear and simple knowledge, which has its
source among us, which can serve as a comfort on our painful
march, and as a thread in the labyrinth of these vast over-
grown territories, a thread which grows gradually larger and
increases our knowledge, until at last it leads us, albeit by a
roundabout way, to a delightful plain I mean the most
important practical truths which serve to content the mind
and to preserve the health of the body, as far as this can be
done by reason.

We see then that what would help us most would be to
unite our labours, to share them advantageously and to
regulate them in an orderly way. But at the present, men
barely touch what is difficult and has not yet been attempted ;
but all run in crowds to what others have already done,
where they cease not from copying and even from striving
with one another. What one has built is first overthrown
by another, who claims to found his reputation on the ruin of
someone else's ; but his own reign is no better established nor
of longer duration. The fact is that they seek glory much
more than truth, and seek rather to dazzle others than to
enlighten themselves. To escape from this unhappy position,
we must abandon the spirit of sect, and the affectation of
novelty. We must imitate the geometers, who are not
Euclideans nor Archimedeans. They are all for Euclid and
all for Archimedes, because they are all for their common
master, that is, divine truth. . . .

. . . We are responsible for our talent to God, and to the
commonwealth. There are so many men of ability of whom
much might be expected, if they would combine what is
serious with what is pleasant. It is not always a question of
writing great works; if each one contributed only a single

MISCELLANEOUS EXTRACTS 239

discovery, we should gain a great deal in a short time. A
single remark or demonstration of consequence is enough to
gain a man immortality. . . .

. . . What century could be more suited to this task than ours,
which will perhaps one day be known as the century of
inventions and wonders? And the greatest wonder that will
be noted in it will perhaps be that great prince, 1 who is the
acknowledged glory of our time, and for whom succeeding
ages will long in vain. I do not mention here his merits as a
statesman and in war, which belong neither to this place nor
to this pen. What he has done for the sciences would alone
be enough to immortalize him. There is no need to describe
him in more detail, he is too unique and too easily recognized
on all hands. Why then seek in the uncertain idea of future
things what exists amongst us in reality, and is even beyond
what an ordinary mind is capable of conceiving? Perhaps
among the great numbers of men of ability in his flourishing
kingdom, and especially among those at his court, which is
an assembly of remarkable persons, there is someone who has
long since drawn up, at his command, a general plan for the
advancement of the sciences, worthy of the sciences and of
the king, and far beyond anything that I should be able to do.

From a draft of a letter to Malebranche. June 1679

. . . The value and even the mark of true science consists
in my opinion in the useful inventions which can be derived
from it. But I have not yet seen that any Cartesian has
found anything useful by means of the philosophy of his
master; whereas we owe at least the beginnings of pendulums
and alleged experiments with a vacuum to the meditations of
Galileo. It seems that the harvest of Descartes' philosophy
is finished, or else that the promise of it was destroyed while
it was still growing by the death of its author. For the
majority of Cartesians are but commentators, and I could
1 Louis XIV.

240 MISCELLANEOUS EXTRACTS

wish that some one of them was capable of adding as much
to physics as you have contributed to metaphysics. What is
more, even if all Descartes' physics were granted, this would
not take us very far. For, after all, the first and second
elements are difficult things to handle. Are we ever likely
to succeed in discovering and executing a formula to compare
with this? Recipe libram unam secundi elementi, unciarn
semis carports ramosi, drachmam materiae subtilis, misce,
fiat aurum. 1 I think we should perhaps need a book as big
as this terrestrial globe to explain the relation between any
given sensible body and the first elements, even supposing
these are genuine and are known. This can be seen from
experiments with the microscope. For there are perhaps as
many as 800,000 tiny animals visible in a drop of water, and
each of these animals is still about as far from the first
elements as we are, since it still has a body which bears
a considerable relation to ordinary animals. There is even
cause to fear that there may not be any elements, everything
in organic bodies being actually divided up ad infinitum. For
if these microscopical animals were again composed of
heterogeneous animals or plants or bodies ad infinitum, it is
obvious that there would be no elements.

Notwithstanding all these considerations I still have a high
opinion of M. Descartes, and perhaps few people recognize
as well as I do the greatness of his mind. In truth, of all the
authors who preceded him and whose works we possess only
Archimedes and Galileo can enter the lists with him. It is
true that few of Archimedes's meditations remain to us;
and although I hold that Galileo invariably makes some fine
comment whenever he is obliged to treat of any matter,
whatever it is, so that it would have been a good thing if
he had had the opportunity to write more, nevertheless I

1 ' Take one pound of the second element, an ounce and a half
of a ramous body, a drachm of subtle matter : mix well. Result :
gold.' The term ' ramous ' was applied (following ancient physics)
to the particles of viscous or rigid bodies.

MISCELLANEOUS EXTRACTS 241

admit that he certainly has not so vast a genius as M.
Descartes. But to make up for this he devoted himself
more to what was solid and useful; whereas M. Descartes,
through his ambition to establish a school, allowed himself
to say a number of things, which were extremely ingenious,
but often uncertain and sterile. All the same, I should
always advise a lover of truth to study his system thoroughly;
for there is to be found in it a wonderful mental dexterity;
and his physics, uncertain as it is, may serve as a model for
the true one, which must at least be as clear and as well
co-ordinated as his. For a romance may be fine enough to
be worthy of imitation by a historian. In short, Galileo
excels in the art of reducing mechanics to science; Descartes
is admirable at explaining by beautiful guesses the reasons
for the effects of nature; and it would have been a good
thing if he had been able to apply himself more to medicine,
which is altogether conjectural, and yet necessary. But
Archimedes, if we can trust the histories, had a talent lacking
in both the others: that is, he had a marvellous mind for the
invention of machines that are useful for the purposes of
living.

Fragment without superscription. 1 (Date unknown)

The best apologia that could be made for M. Descartes
would be to complete his hyperbolic spectacles, which are
the only useful things he discovered if it were practicable
to do so; and I could wish that Fr. Malebranche and others,
who assume the task of defending everything he said, were
obliged to do it.

From a letter to Basnage. 16/26 July 1695

The death of the illustrious M. Huygens is an inestimable
loss. Few know this as well as I do. He equalled, in my

1 Taken from Bodeman's Catalogue of the Leibniz M 55. in the
Royal Public Library at Hanover (1895).

242 MISCELLANEOUS EXTRACTS

opinion, the reputation of Galileo and Descartes, and, with
the help of what they had done, he surpassed their discoveries.
In a word, he was one of the chief ornaments of our time. I
often exhorted him to give us his reflections, even if it were
only in scraps and in an informal manner. I hope that his
book on the system of the world and the internal constitution
of the planets has been finished. But as he was accustomed
to putting his reflections in writing in pretty good order, I
have hopes that a great treasure may be found among
his papers.

From the l Theodicy 9 (Preliminary Discourse). 1710

87. ... It is to be hoped that M. Bayle now finds himself
surrounded by that illumination which we lack here below,
since there is every ground to suppose that he was never
lacking in good will.

From the same work

if 2. ... This view that has been held regarding Mr. Hobbes,
that he taught an absolute necessity of all things, has seriously
injured his reputation, and would have done him harm, even
had it been his only error.

173. Spinoza went further; he appears to have expressly
taught that there is a blind necessity, having denied the
Author of things understanding and will, and imagining that
the good and perfection have relation only to us and not to
Him. It is true that Spinoza's opinion on this point is not
without obscurity, for he attributes thought to God after
having deprived Him of understanding: cogitationem, non
intellectum concedit Deo. There are even passages in which
he relents a little on the question of necessity. However,
as far as I can understand him, he does not recognize any
goodness in God, properly speaking, and teaches that all
things exist by the necessity of the Divine nature, without

MISCELLANEOUS EXTRACTS 243

any choice on the part of God. We will not amuse ourselves
here in refuting so bad, and indeed so inexplicable, an opinion.

From a letter to des Bosses. 15 March 1715

We rightly regard bodies as being things, for even phe-
nomena are real. But if any one seeks to regard bodies as
being substances he will surely need some new principle of
real unity. The man in Ireland l who impugns the reality of
bodies seems neither to give adequate reasons nor to explain
sufficiently what is in his mind. I suspect that he is one
of those people who seek to become famous by their paradoxes.

From a letter to Thomas Burnett. 8/18 May 1697

... I find that it is not possible to regulate currency without
regulating at the same time the price of merchandise and
commerce, at any rate in part, since silver is itself a piece of
merchandise. And I find that it involves a logical circle
if we seek to estimate the value of a piece of silver by money,
and thus that what our lawyers are accustomed to call
bonitas extrinseca? when they say for example that an ecu
is worth so many gray, 3 is at bottom a chimera. As Mr.
Newton holds a position of responsibility in regard to matters
of currency, I should place great reliance on his judgment on
this point, as well as on every other question ; as also on the
opinion of Mr. Locke, since he has made a profound study of
commerce. ... I would not have it thought in the world that
I am the kind of man to set Mr. Newton problems of mere
curiosity. If I wished to set him problems, I should choose
more useful ones though I recognize that M. Bernoulli's
problems are good ones. But more important things are

1 Berkeley.

1 i.e. extrinsic valuation, as opposed to intrinsic weight or
fineness.

An ecu was a French standard silver coin; a gros was a Dutch
copper coin of small value.

244 MISCELLANEOUS EXTRACTS

needed to occupy such a man as Mr. Newton. ... I beg you to
present my compliments to Mr. Newton and to assure him
that I hold him ever in the highest esteem, and that I do not
accept the excuses he gives for not yet having given to the
public his meditations on colours and other matters. A man
of his power should prefer the public good to all other con-
siderations; and everything which comes from his pen is so
generally esteemed that he has no ground for complaining
of the ingratitude of his readers. I beg you to stir up Mr.
Newton's friends to put pressure on him and to give him
no quarter. . . .

From a letter to Hartsoeker. 10 March 1707

. . . You say, sir, that homogeneous rays change colour when
they penetrate bodies of another colour. Yet you yourself
adduce in your book an experiment which supports Mr.
Newton's opinion as opposed to yours. For you follow him
in stating that bodies which otherwise are blue appear red,
when they are exposed to a homogeneous red light: and the
same with the others. For the rest, it is possible that a white
body absorbs or at least diverts elsewhere as many rays as a
coloured body, if we suppose, for instance, that this white
is composed of red and blue parts, or, to speak more exactly,
of parts some of which are fitted to reflect red rays and
others blue rays, and in this way the blue parts will cause
the loss of many red rays, and vice versa. And if we conceive
what is ordinarily white as composed of little mirrors, it is
clear that a good part of the mirror is black and diverts the
rays elsewhere. Thus from the fact that a yellow colour
sometimes seems as vivid as a white colour, it does not follow
that rays other than the yellow ones are sent to us to make
the body appear yellow: this would be changing homogeneous
rays which are not yellow into yellow. Mr. Newton mentions
at the end of his work a number of points which he leaves for

MISCELLANEOUS EXTRACTS 245

others to investigate. They are worthy of your attention,
as you have applied yourself to this matter.

From a letter to Bourget. 5 August 1715

I cannot say anything about the details of the generation
of animals. All that I think I can affirm is that the soul of
every animal has pre-existed, and has been in an organic
body which at last, by many changes, involutions and
evolutions, has become the present animal. Your conjecture
that every animal in the human seed will ultimately achieve
rationality is ingenious and might be true, but I do not see
that it is necessary. If there were a good number of them
which remained mere animals, there would be no harm done.
I would not dare to affirm that the animals which M. Leeu-
wenhoek has rendered visible in the seed are exactly those
which I have in mind; but neither would I dare to affirm that
they are not so; and I am waiting impatiently to see what M.
Vallisnieri is going to give us in refutation of them. In the
meantime I should not wish to speak as decisively as you do,
Sir, when you say that M. Leeuwenhoek's opinion is one of the
emptiest of fables. M. Huygens, who was one of the most
penetrating men of his time, did not think so. The prodigious
quantity of these animals (which constitutes your first objec-
tion) is in no way against it. A similar abundance may be
found in the seeds of some plants. There are some, for
example, whose grain consists of a very fine dust. Also, I
do not see that there is any difficulty in the introduction into
the egg of one of these animals to the exclusion of the other
(your second objection). A great many appear to be intro-
duced, because they are so small, but there appears to be
only one place, a punctum saliens * so to speak, which can
receive them with effect. And this also satisfies your third
objection, which is that their extreme smallness is out of

x * salient point'; in old medical usage, the heart as it first
appears in an embryo.

246 MISCELLANEOUS EXTRACTS

proportion to the egg. The case is the same as when a fruit
is very large, but its seminal part is very small and insensible.
The fourth objection is that the egg and the foetus are the
same animal; but this proposition is not proved; it might be
that the egg was only a receptacle suited for giving growth
and for assisting transformation. The fifth objection is that
according to modern zoologists, and particularly according
to M. Vallisnieri, the animals which are found in the sperms
must be animals of their species which propagate and per-
petuate themselves, exactly in the same way as occurs with
the other animals which are known to us. With this I am
in entire agreement: but in my opinion, even if these animals
were the true seminal animals, they would none the less be a
particular species of living things, of whom some individuals
would be raised to a higher stage by a transformation.

However, I would not venture to assert that your view is
false, namely that the animal to be transformed is already
present in the egg when conception takes place. But the
view that it enters it by the conception seems more likely.
Do not then let us decide anything with too much assurance,
and above all let us not treat ill a man like M. Leeuwenhoek,
to whom the public owes thanks for the pains he has taken
in his researches. It is, of course, most permissible to oppose
his view, and I am very glad that it should be done, but it is
not just to despise him. There is one difficulty which seems
to me to be common to all the hypotheses, and on which I
should like to have M. Vallisnieri's opinion; namely, why in
the copulation of certain species of animals a single egg is
generally fertilized, and why, in these species, twins are
comparatively rare.

From the same letter

. . . Two hypotheses are possible: one that nature is always
equally perfect, the other that it is always growing in per-

MISCELLANEOUS EXTRACTS 247

fection. If it is always equally perfect, but variable, it is
more probable that there is no beginning. But if it is always
growing in perfection (supposing that it is not possible to give
it the whole of perfection all at the same time), the matter
could still be explained in two ways, that is to say by
the ordinates of the hyperbola Z?, or by the triangle C.
On the hypothesis of the hyperbola, there would be no be-
ginning, and the instants or states of the world would have

B A c

i i

\

been growing in perfection from all eternity; but following
the hypothesis of the triangle, there would have been a
beginning. The hypothesis of equal perfection would be that
of the rectangle A. I do not yet see the way to show
demonstratively which we ought to choose by pure reason.
However, although on the hypothesis of growth the state of
the world could never be perfect absolutely, taken at any
given instant, yet the actual sequence would none the less
be the most perfect of all possible sequences, for the reason
that God always chooses the best possible. . . .

248 MISCELLANEOUS EXTRACTS

Fragment without superscription. 1 (Date unknown)

Goodness is in the will, wisdom is in the understanding.
Wherein is power? Someone will say it is in body or matter.
But body is not a substance unless it be taken to be a unity;
and moreover there is power in God who is without matter.
It is true, however, that power is in what corresponds ana-
logically to matter, that is to say, in the common subject of
goodness and wisdom, which is the source of changes or
actions. This subject may be called matter in created
things.

Fragment without superscription. 2 (Date unknown)

I have learnt by experience that nothing defeats courage
and removes the taste for beautiful things more than the
importunate reflections we make on human misery, and on
the vanity of our undertakings. It is the sole stumbling-
block of noble minds, on which it is all the easier to fail the
more exalted one's genius. For ordinary minds do not pause
over this great consideration about the future which in some
sort includes the whole universe: but in compensation they
are happier, for they taste apparent goods, without its occur-
ring to them to destroy the pleasure by too exact a reflection.
And since a happy folly is better than a bitter prudence, I
think we should do well to turn deaf ears to reason and give
ourselves up to custom, or else to reason for our diversion
only, if there be no means of reconciling wisdom with con-
tentment. But, God be praised, we are not so unfortunate,
and Nature would be a stepmother, if that which makes our
perfection were the cause of our wretchedness.

1 Taken -from Bodeman's Catalogue (cf. p. 241, note).
1 Ibid.

MISCELLANEOUS EXTRACTS 249

Comment on a book entitled: 'Reflections on Great Men
who have died jesting*. l (Date unknown)

This little book is written with wit and learning, but there
are signs in it of some moral laxity. I strongly approve that
one should die joyfully, and consider that the Italian lawyer
who gave orders that his funeral should be celebrated with
rejoicings performed the action of a wise man, although it
has been contested. But I should not wish an event which
merits all our attention to be treated as of no account. This
could be approved only by those who are ignorant of the
dignity of man, and do not know that Providence put him at
his post to render account of his movements; of which one
of the most important is the manner of leaving it. Our
author very rightly remarks that death is more to be desired
than feared, but he adduces a bad reason for this when he
says that man is not born to be happy. This is humorous,
indeed. These gentlemen want to be unhappy by force,
while charitable Nature has granted them almost everything
necessary for their good. It is most untrue that there is
ordinarily more unhappiness than happiness in life. The
wretched thoughts and complaints against Nature of some
persons are very unjust. It seems to me that the author
rails in comfort against evils which he does not feel. Reason,
which can make death pleasant to us, is not the misfortune of
this life, but the greatest happiness of another. The author
himself defends troubles on the ground that they make for
vivacity. He is sure that a state which left nothing to be
desired, would make us stupid. But I am not of his opinion
when he holds that the verses which Ovid wrote in exile are
better than those he wrote when in love. He does not seem
to me to have rightly reported the words of M. Gassendi,
when he was in danger of dying. M. Guy Patin, who was not

1 Taken from Bodeman's Catalogue (cf. p. 241, note).

250 MISCELLANEOUS EXTRACTS

too much of a preacher, kept on telling him that he must
think of death. M. Gassendi replied with this line from
Virgil:

Omnia praecepi atque animo mecum ante peregi. 1

M. de Meaux 2 and Madame de Maintenon have assured me
that death came upon M. Pellisson by surprise, and that he
did not by any means scorn the rites of the Church. I prefer
to believe them rather than the author of this book, who
attributes an unworthy avowal to a person who showed me
friendship, and whom I, like most others, held in esteem.

From a letter without address or date 3

I realized, sir, from the little talk I had the honour to have
with you, that you meditate deeply on the nature of human
freedom. And this it is which drives me to expound to you
more clearly what I referred to in conversation, so that I may
profit by your opinion of it. I hold that it is in the interests
of piety and faith to reconcile the way in which our will acts
not only with the dogmas of faith, but also with the great
principles of reason, which hold sway everywhere else, and
are the foundations of our knowledge. Otherwise we seem
to be yielding the victory to impious men and atheists, or at
the least to be confirming and strengthening them in their
errors. This is why I never could fancy the opinion of those,
who maintain that the principle of contradiction does not
apply in Divinis, and that we do in fact find an exception to
it in the case of the Trinity of the Divine Persons, as is
admitted to some extent by those who introduce certain
virtual distinctions. Now it is the same reason which

1 ' I have imagined it all and have gone over it all beforehand
in my mind. '
1 Bossuet.
1 Taken from Bodeman's Catalogue (cf. p. 241, note).

MISCELLANEOUS EXTRACTS 251

makes me doubt whether it is fitting to say that another
principle, which is of hardly less general application than the
principle of contradiction, does not apply with regard to
freedom the principle, namely, that nothing ever takes
place without its being possible for one who knew everything
to give some reason why it should have happened rather than
not. All the more so, because it seems to me that this
principle is of just the same use to us in matters of contin-
gency, as is the principle of contradiction in matters of
necessity. It is for this reason that the laws of motion
depend on it, because they are not of geometrical necessity,
since they originate from the will of God, regulated by
wisdom. Now since the principle of contradiction is the
principle of necessity, and the principle that a reason must
be given is the principle of contingency, it seems to me that
we must not except freedom from them. Archimedes takes
it for granted that a balance will not tip more in one direction
than in the other, when everything is equal on both sides,
and in the same way all those who reason about morals and
politics, with a view to discovering about human actions,
tacitly make use of this same foundation, that there is always
a reason or cause which inclines the will. We shall, more-
over, never find a contrary instance, and no one but a Scholas-
tic, buried in abstractions, thinks otherwise. To show that
the will ought to be excepted it would be necessary to have a
means of determining the limitation of this principle a
priori. This we can never find; and any foundation which
might be adduced for such a distinction will always go further
than we wish. It therefore seems to me that we do not need
to seek even this exception, and that free choice is not
incompatible with the general principle I have just estab-
lished. To explain myself more clearly: I say that Adam
sinned without necessity, although He who knows every-
thing could give a reason why he rather let himself sin than
remain in innocence. Even Holy Writ, in the account it

252 MISCELLANEOUS EXTRACTS

gives of the method adopted by the serpent to betray Eve,
also seems to hint that there was some reason or inclination
which prevailed over the will of Eve. It looks as though the
soul is never in that state of complete indifference, in which
nothing matters whether within or without. There is always
a reason, that is to say a greater inclination, for what has in
fact been chosen, which may come not only from arguments
good or bad, but also from passions, habits, dispositions of
the organs of the mind, external impressions, greater or less
attention, etc. But this inclination does not master freedom,
although it inclines it. There is a great deal of difference be-
tween a necessary cause and a certain concomitant. It is my
view also that if we established the opposite, and claimed
that the perpetual accompaniment of a stronger reason for
choice destroys freedom, it would follow that inclination or
the strongest reason would destroy freedom on every occasion
that it accompanied it. From which it would follow further
that we should almost never be free, since the cases when we
are completely indifferent, or have a metaphysical freedom
of choice, are at the least extremely rare, if they ever occur.
Thus when we choose what is best, because it is best, it would
be from necessity. Consequently the most perfect actions
would be the least free and the least praiseworthy, since it is
in freedom that we seek the reason for praise and blame, or
rewards and punishments. The more perfect and the more
inclined towards good a man was, the less free and praise-
worthy he would be. Thus man would have to be reduced
to a complete nudity, and despoiled of good qualities and
graces, if he were to be allowed any merit. This is a vision
favoured by some of our moderns, who seek the notion of
freedom in indifference; which is as far removed from good
sense as are their doctrines about probability and about
knowledge of the badness of the action being necessary for
sin. Whence has recently arisen that extraordinary dis-
tinction between philosophical and theological sin, which is

MISCELLANEOUS EXTRACTS 253

upheld by certain authors who maintain that an assassination
or an adultery is not a mortal sin, when the man who com-
mits it does not actually reflect that he is offending God;
because they imagine that otherwise the action is not suffi-
ciently voluntary, that is to say, according to them, suffi-
ciently indifferent, when the man does not give sufficient
thought to everything which might dissuade him from it.

Leibniz 9 s Philosophical Dream. 1 (Date unknown)

I was happy to be among men, but not happy about human
nature. Often I thought with sorrow of the evils to which
we are subjected, of the short duration of our life, the vanity
of glory, the inconveniences which spring from pleasure, the
illnesses which crush our very spirit; finally the annihilation
of all our glories and all our perfections in the moment of
death, which seems to reduce to nothing the fruits of our
labours. These meditations made me melancholy. I had a
natural love of doing good and knowing the truth. Yet it
looked as though I were taking pains to no purpose, and as
though a fortunate crime were better than an oppressed
virtue, and the folly which satisfies preferable to the reason
which gives pain. But I resisted these objections, and the
better part triumphed in my mind through the consideration
of the Divinity, who must have ordered everything properly,
and who kept up my hopes by the expectation of a future
capable of making up for everything. The struggle in me
was renewed at the sight of any great disorder, either among
men, when I beheld injustice triumphant and innocence
afflicted, or in nature, when tempests or earthquakes made
havoc of towns and provinces, and caused the death of
thousands without distinction between the righteous and
the wicked, as if nature took no more account of us than we

1 Taken from Bodeman's Catalogue (cf. p. 241, note). The
superscription is in the hand of a librarian.

254 MISCELLANEOUS EXTRACTS

take of the ants and worms we come across on our path.
I was greatly moved by these spectacles, and could not
prevent myself from pitying the condition of mortal men.

One day, wearied by these thoughts, I fell asleep, and
found myself in a dark place, which was like a subterranean
cave, very large and very deep, and swarming with men, who
with strange haste pursued in this darkness wandering fires
which they called honours, or tiny shining flies under the
name of riches; many there were who searched on the ground
to find shining pieces of rotten wood, which were called
pleasures. These unlovely lights had each its followers;
there were some who changed their course, and some who
abandoned the pursuit altogether, through tiredness or
through despair. Many of those who were running blindly
about, and who often thought they had attained their goal,
fell over precipices, whence naught was heard but their
groans; some were stung by scorpions and other venomous
creatures, which made them wretched and often mad with rage.
But neither these examples, nor the arguments of some better
informed persons, prevented the others from running the
same risks, or from fighting in order to forestall others, or to
prevent themselves from being forestalled. In the vault of this
great cave, there were little chinks and barely perceptible
cracks through which filtered some traces of the light of day,
but it was so weak that much attention was required for it
to be noticed. Often there were heard voices which said:
'Hold, mortals; whither go ye, wretched that ye are?' Others
cried, 'Lift up your eyes to heaven'; but they did not stop,
and only lifted their eyes to pursue these dangerous trifles.
I was one of those who was extraordinarily struck by these
voices. I kept on looking up, and at last I saw the little
light which required so much attention. It seemed to me to
grow in proportion as I looked fixedly at it. My eyes
became as it were imbued with its rays, and when I used
them immediately afterwards to see where I was and whither

MISCELLANEOUS EXTRACTS 255

I was going, I was able to discern what was around me,
which was enough to save me from the dangers. A venerable
old man, who had long been wandering in the grotto, and
whose thoughts were not unlike mine, told me that this light
was what in our world is called good sense and reason. I
often changed my position to examine the different chinks
in the vault through which this little light came, and when I
was stationed in one place, where several lights could be
perceived at the same time from their true point of view, I
found an assemblage of rays which greatly enlightened me.
This occupation was of great benefit to me, and made me more
capable of acting in this obscurity. Finally, after having
attempted several views, I was led by my good star to a
place which was the sole and most advantageous spot in
the grotto destined for those whom the Divinity wished to
withdraw altogether from these dark regions. Barely had I
begun to look up when I was surrounded by a great light
gathered from all sides, and the whole grotto and its horrors
were fully revealed to my eyes. But a moment afterwards
a dazzling brightness took me by surprise. Presently it took
shape, and I saw before me the appearance of a young man
whose beauty charmed my senses. His mien had a majesty
which inspired me with veneration mingled with awe, but the
gentleness of his glances reassured me. But I began to feel
a weakness overcoming me, and was about to faint, when I
felt myself touched by a branch imbued with a marvellous
liquid which I cannot compare with anything I have ever
felt, which gave me the strength necessary to bear the
presence of this celestial messenger. He called me by my
name, and said in gracious tones: 'Give thanks to the Divine
goodness which withdraws you from this mob'. At the same
time he touched me a second time, and at that moment I felt
myself raised up. I was no longer in the cave, I no longer
saw a vault above me, and I found myself on a high mountain
which revealed to me the face of the earth. I saw in the
T95

256 MISCELLANEOUS EXTRACTS

distance anything that I wished to look at only in a general
way; but when I considered a particular place fixedly, im-
mediately it grew, and in order to see it as if close at hand,
I needed no other telescope than my attention. This gave
me a wondrous pleasure, and emboldened me to say to my
guide: 'Powerful spirit, for I cannot doubt but that you are
one of the celestial angels, who pay court from near at hand
to the Sovereign of the Universe, since you have been ready
to enlighten my eyes, do as much for my mind'. He seemed
to me to smile, and to take pleasure in hearing my wish.
'Your desires are granted/ he said, 'since you desire wisdom
rather than the pleasures of the vain spectacles which the
world offers to your gaze. But you will lose nothing of what
is solid in these same spectacles. You will see them with
eyes quite differently enlightened. Your understanding,
being fortified from on high, will discover everywhere the
brilliant enlightenments of the Divine Author of things; you
will observe only wisdom and happiness where men cus-
tomarily find nothing but vanity and bitterness. You will
be satisfied by your Creator; you will be enchanted by the
sight of His works. Your admiration will not be the result of
ignorance, as is that of the common herd. It will be the
fruit of the knowledge of the glories and wonders of God.
Whereas among men secrets are despised when they are
discovered, though they were previously regarded with
astonishment; you will find that when you are admitted into
the heart of nature, the further you go the greater will be
your delights, because you will be only at the beginning of a
chain which goes on to infinity. The pleasures which charm
your senses, and that fabled Circe who changes men into
beasts, will have no power over you, if you bind yourself to
the beauties of souls which never perish and never cause
displeasure. You will be of our company, and will go with us
from world to world, from discovery to discovery, from per-
fection to perfection. You will pay court with us to the

MISCELLANEOUS EXTRACTS 257

Supreme Substance, which is beyond all worlds and which
fills them without dividing Itself in doing so. You will be at
one and the same time before His throne and among those
who are distant from it. For God will establish His seat
in your heart, and the heavens follow Him everywhere. Go
then and lift up your mind above whatever is mortal, and
whatever perishes, and bind yourself only to the eternal
verities of the light of God. You will not always live here
below this mortal life, so like that of the brutes; a time will
come when you will be wholly freed from the chains of this
body. Make good use, therefore, of the time which Providence
grants you here, and know that your perfections to come will be
proportioned to the care you take here below to attain them/

From the ' Theodicy ' . 1710

405. I had intended to stop at this point, having answered
(so it seemed to me) all M. Bayle's objections on this subject,
which I could find in his works. But recalling Laurentius
Valla's dialogue Of Free-will, which was written against
Boethius and which I have mentioned before, I thought it
would be fitting to give a summary of it here, keeping the
dialogue form, and then to go on from the point at which he
stops, continuing the story which he begins. My aim is not
so much to brighten up the subject-matter, but rather to
explain myself at the end of my discourse in the clearest and
most popular manner that is open to me. . . .

ANTONY. I know that you can give me wings, like a
second Daedalus, to escape from the prison of ignorance, and
to soar to the region of truth which is the dwelling-place of
souls. I have derived no satisfaction from the books I have
read, no, not even from the celebrated Boethius, who has
won general approbation. I know not whether he himself
has rightly understood what he says about God's under-
standing, and about eternity which transcends time. I beg

258 MISCELLANEOUS EXTRACTS

you to give me your opinion about the way of reconciling
foreknowledge with freedom.

LAURENTIUS. I fear that I shall shock many people if I
refute this great man. I will, however, subordinate this
fear to my regard to the entreaties of a friend, on condition
that you promise me

ANT. What?

LAUR. That after you have dined with me you will not ask
for supper also. By this I mean that you will be satisfied
with the solution of the question you have put me, without
asking me another.

ANT. I promise. Here is the heart of the difficulty. If
God foresaw the treachery of Judas, it was necessary that
Judas should betray; it was impossible that he should not
betray. There is no obligation to perform the impossible.
Therefore he did not sin, and did not deserve to be punished.
This destroys justice and religion, together with the fear
of God.

LAUR. God foresaw the sin, but He did not force the man
to commit it. Sin is voluntary.

ANT. This volition was necessary, since it was foreseen.

LAUR. If my knowledge does not give existence to things
past or present, neither can my foreknowledge give existence
to future things.

ANT. This comparison is misleading. Neither the present
nor the past could be changed; they are already necessary.
But the future, in itself susceptible of change, becomes,
through foreknowledge, fixed and necessary. Let us suppose
that a pagan god boasts that he knows the future: I should
ask him which of my feet I shall put foremost, and then I
should do the opposite of what he predicted.

LAUR. This God knows what you will want to do.

ANT. How can He know, since I shall do the opposite of
what He says, and I assume He will say what He thinks ?

LAUR. Your supposition is a false one. God will not

MISCELLANEOUS EXTRACTS 259

answer you, or, if He did answer you, your veneration for
Him would make you hasten to do what He said: His predic-
tion would be to you a command. But we have changed our
question. We are not concerned with what God will predict,
but with what He foresees. Let us return to foreknowledge,
and distinguish between the necessary and the certain. It
is not impossible that that which is foreseen will not happen,
but it is infallible that it will happen. It is possible for me
to become a soldier or a priest, but I shall not become one.

ANT. That is where I have you. The philosophers' Rule
demands that whatever is possible should be considered as
existing. But if what you say is possible, that is to say an
event different from what has been foreseen, did actually
happen, then God would have been mistaken.

LAUR. Philosophers' Rules are not oracles for me. This
one in particular is not accurate. Two contradictories are
often both of them possible, but can they therefore both of
them exist ? But to enlighten you further, let us suppose that
Sextus Tarquinius comes to Delphi to consult the oracle of
Apollo and receives the answer:

Exul inopsquc cades irata pulsus ab urbc. 1

The young man complains: C I have brought you a royal
present, O Apollo; and yet you reveal to me so unhappy a
fate*. Apollo answers: 'Your present is pleasing to me, and
I perform what you ask of me; I tell you what will happen.
I know the future but I do not make it. Go and complain to
Jupiter and to the Fates'. It would be absurd of Sextus,
would it not, if after this he went on complaining to
Apollo?

ANT. He will say: 'I thank you, holy Apollo, for not
having paid me with silence, for having disclosed to me the
truth. But how comes it that Jupiter is so cruel to me, and

1 'You will die poor and in exile, driven in anger from your
fatherland.'

260 MISCELLANEOUS EXTRACTS

prepares so hard a fate for an innocent man, who is religious
and who worships the gods ? '

LAUR. 'You an innocent man?' answers Apollo. 'Know
that you will be proud, that you will commit adulteries, and
that you will be a traitor to your country/ Could Sextus
answer: 'It is you who are the cause of this, Apollo; you
force me to do it by foreseeing it' ?

ANT. I admit that he would have lost his reason if he
answered thus.

LAUR. Neither then can the traitor Judas complain of
God's foreknowledge. And this is the solution of your
question,

ANT. The satisfaction you have afforded me has exceeded
my hopes; you have done what Boethius was unable to do.
I shall be grateful to you all my life.

LAUR. But let us pursue our story a little further. Sextus
says: 'No, Apollo, I will not do what you say'.

ANT. 'What!' says the god, 'am I then to be a liar? I
repeat again you will do everything that I have just said.'

LAUR. Perhaps Sextus will pray to the gods to change
his fate, to give him a better heart.

ANT. He will receive the answer:

Desinefata deumflecti sperare precando. 1

He will not be able to give the lie to divine foreknowledge.
But what will Sextus say ? Will he not burst into complaints
against the gods? Will he not say: 'What? Am I not then
free ? Is it not in my power to follow virtue ? '

LAUR. Apollo may say to him: 'Know, my poor Sextus,
that the gods have made every man what he is. Jupiter
has made the wolf ravening, the hare timid, the ass stupid,
the lion brave. He has given you a soul which is wicked and
incorrigible. You will act in accordance with your nature,

1 ' Hope not that the fates of the gods may be turned aside
by prayers/

MISCELLANEOUS EXTRACTS 261

Jupiter will treat you as your actions deserve. By the Styx
he has sworn it'.

ANT. I confess that it seems to me that Apollo, in excusing
himself is accusing Jupiter more than Sextus. And Sextus
would reply: 'Jupiter condemns in me his own crime it is
he alone who is guilty. He could have made me quite other
than I am. But, made as I am, I am bound to act as he has
willed. Why then does he punish me? Was I able to resist
his will? 1

LAUR. I confess that I also am brought to a standstill. I
have called the gods Apollo and Jupiter on to the stage,
to distinguish for you between the foreknowledge and the
providence of God. I have shown that Apollo, or foreknow-
ledge, is not injurious to freedom, but I cannot give you
satisfaction concerning the decrees of the will of Jupiter, that
is to say the commands of providence.

ANT. You have rescued me from one abyss, and you plunge
me into a deeper one.

LAUR. Remember our contract. You have dined with me,
and you are asking me for supper also.

ANT. Now I see your adroitness. You have caught me,
it is not an honest contract.

LAUR. What more can I do? I have given you wine and
meat of my own growing, such as my little estate can provide.
Nectar and ambrosia you must ask of the gods such divine
food cannot be found among men. Listen to St. Paul, that
chosen vessel who was caught up into the third heaven, who
heard there unspeakable things. He will reply by invoking
the parallel of the potter, the incomprehensibility of the ways
of God, and our admiration for the depth of His wisdom.
Yet it is well to note that we do not ask why God foresees the
event, for that we understand; it is because it will happen.
But we ask why He orders it so, why He hardens the heart
of one, why He takes pity on another. We do not know
what reasons He may have for it, but the fact that He is very

262 MISCELLANEOUS EXTRACTS

good and very wise is enough to make its judge them good. And
as He is just also, it follows that His decrees and His opera-
tions do not destroy our freedom. Some have sought for a
reason. They have said that we are made of a corrupt and
impure mass of mud. But Adam and the angels were made
of silver and gold, and they sinned none the less. Some-
times, also, our hearts are hardened after regeneration. We
must then seek another cause of evil, and I doubt if even the
angels know it. For they continue happy and praising God.
Boethius paid more attention to the answer of philosophy
than to St. Paul's. This is the cause of his failure. Let us
believe in Jesus Christ, who is the virtue and wisdom of God ;
He teaches us that God desires the salvation of all, that He
desires not the death of a sinner. Let us trust in the Divine
mercy, and let us not, through our vanity and our malice,
become incapable of enjoying it.

This dialogue of Valla's is beautiful, although there are
points to criticize in it here and there. But its chief defect
is that it cuts the knot, and seems to condemn Providence
under the name of Jupiter. Let us therefore proceed further
with our little fable. Sextus, after leaving Apollo at Delphi,
goes to seek Jupiter at Dodona. He offers sacrifices and then
sets forth his grievances. 'Why have you condemned me,
O great God, to be wicked and to be unfortunate? Change
my lot and my heart, or recognize your fault.' Jupiter
answers: 'If you are ready to renounce Rome, the fates
shall spin you other destinies; you shall become wise, you
shall be happy'. 'Why must I renounce the hope of a
crown?' asks Sextus; 'can I not be a good king?' 'No,
Sextus/ answers Jupiter, 'I know best what you need. If
you go to Rome you are lost.' Sextus could not make up
his mind to so great a sacrifice, left the temple, and gave
himself up to his fate. Theodorus, the High Priest, who had
witnessed the dialogue between the god and Sextus, addressed

MISCELLANEOUS EXTRACTS 263

Jupiter thus: 'Your wisdom is worthy of adoration, great
Master of the gods, you have convinced this man of his fault.
Henceforth he must attribute his misfortunes to his evil will;
he has not a word to say. But your faithful adorers are
astonished: they would wish to admire your goodness as well
as your greatness. It rested with you to give him another
will'. 'Go to my daughter Pallas/ said Jupiter, 'she will
teach you what I had to do.'

Theodoras journeyed to Athens. He was commanded to
sleep in the temple of the goddess. As he dreamed, he found
himself transported into an unknown country, where stood a
palace of inconceivable brightness and vast size. The god-
dess Pallas appeared at the gate encircled with rays of
blinding majesty.

Qualisque videri
Coelicolis et quanta solet. 1

She touched the face of Theodorus with an olive branch,
which she held in her hand. He immediately became able
to bear the divine brilliance of the daughter of Jupiter and
of all the things she was to show him. 'Jupiter, who loves
you/ she said, 'has entrusted you to me to be instructed.
Here you see the palace of the Fates, whose guardian I am.
Here are representations, not only of what happens, but also
of everything that is possible. Jupiter reviewed them all
before the beginning of the existing world, arranged the
possibilities into worlds, and chose the best of them all.
Sometimes he comes to this place to give himself the pleasure
of going through things, and of renewing his own choice,
with which he cannot fail to be satisfied. I have only to
speak and we shall see an entire world, which my father could
have produced, and in it will be represented everything that
can be required of it. And by this means it is possible to

1 ' In the guise and grandeur in which she is wont to appear
before the denizens of heaven.'

264 MISCELLANEOUS EXTRACTS

know too what would happen, if such and such a possibility
had to exist. And if the conditions are not clearly enough
determined, there will be as many such worlds as one can
desire, different from one another, which answer the same
question in different ways, and in as many ways as is possible.
You studied geometry when you were young, like all well-
educated Greeks. You know, then, that when the con-
ditions of a point we are looking for do not sufficiently
determine it, and there are an infinite number of them, they
all fall in what the geometricians call a locus, and this locus
at least (which is often a line) is determined. In the same
way you can imagine an ordered series of worlds, all of which
(and they alone) contain the case you are concerned with,
and which vary its circumstances and consequences. But if
you suppose a case which differs from the actual world no
more than in one single definite thing and in the consequences
of that, then one certain determined world will afford the
answer. These worlds are all here; that is to say in idea.
I will show you some where you will find, not exactly the
same Sextus whom you have seen (that is impossible, since
he carries always with him what he is to be), but Sextuses
like him, who possess all that you already know of the true
Sextus, but not everything which is already in him without
being perceived, nor consequently all that is yet to happen
to him. You will find in one world a Sextus very happy and
exalted, in another a Sextus satisfied with a mediocre con-
dition, Sextuses of all kinds and of an infinite number of
types/

Thereupon the goddess led Theodoras into one of the
apartments. When he was inside it was no longer an
apartment, it was a world,

Solemque suum, sua sidera norat. 1

By the command of Pallas, Dodona appeared with the
1 'A sun of its own it knew, and stars of its own.'

MISCELLANEOUS EXTRACTS 265

temple of Jupiter, and Sextus leaving it. He was heard to
say that he would obey the god. He went to a town lying
between two seas, like Corinth. There he bought a little
garden, and while digging in it he found treasure. He
became a rich man, loved and respected, and died in ripe
old age, beloved by the whole city. Theodorus saw his whole
life at a glance, like a performance on the stage. In this apart-
ment lay a large book filled with writing. Theodorus could
not refrain from asking what it meant. 'It is the, history of
the world we are now visiting/ answered the goddess, 'it is
the book of its destinies. You have seen a number on the
forehead of Sextus look up in the book the place the
number indicates.' Theodorus looked it up and found there
the story of Sextus in more detail than the one he had seen
in brief. 'Put your finger on whatever line you please/ said
Pallas, 'and you shall see represented in actual fact in all its
details what the line tells in outline.' He obeyed, and saw
appear all the details of a part of the life of Sextus.

They passed into another apartment, and behold ! another
world, another Sextus, who, leaving the temple with the
determination to obey the god Jupiter, went to Thrace.
There he wedded the king's daughter, his only child, and
succeeded him. He was adored by his subjects. They went
to other rooms and beheld ever fresh scenes.

The apartments were arranged in a pyramid; the higher
up they were the more beautiful they became, and the more
beautiful the worlds they represented. At last they reached
the topmost apartment, which completed the pyramid, and
which was the most beautiful of all. For the pyramid had a
beginning, but there was no end to it to be seen. It had an
apex but no base; it grew and grew to infinity. This was
because, as the goddess explained, out of an infinity of possible
worlds, there is the best of all possible worlds, otherwise God
would not have made up his mind to create one at all, but
there is no world which has not less perfect ones below it, and

266 MISCELLANEOUS EXTRACTS

that is why the base of the pyramid stretches down to in-
finity. When Theodorus entered this topmost apartment, he
was caught up in an ecstasy. The goddess had to come to
his aid and restore him by putting a drop of divine liquid on
his tongue. He could not contain himself for joy. ' We are
in the actual world,' said the goddess, 'and you are at the
source of happiness. This is what Jupiter is preparing for
you here, if you continue to serve him faithfully. Here is
Sextus as he is and as he actually will be. He rushes from
the temple in a rage, he scorns the advice of the gods. You
can see him travelling to Rome, bringing destruction with
him, violating the wife of his friend. Here he is exiled with
his father, defeated, wretched. If Jupiter had here taken a
Sextus who was happy at Corinth, or who was king of Thrace,
it would no longer have been this world. Yet he could not
fail to choose this world, which surpasses all others in per-
fection, and which forms the apex of the pyramid: otherwise
Jupiter would have renounced his wisdom, and would have
banished me, his daughter. You see that my father did not
make Sextus wicked. He had been wicked from all eternity,
and always of his own free will. Jupiter did nothing but
grant him existence, which his wisdom could not refuse to
the world which contains him. He made him pass from the
region of possible to that of actual beings. The crime of
Sextus serves great ends: it makes Rome free, from it is born
a great empire, which will furnish great examples. But that
is nothing compared with the totality of this world, whose
beauty you will admire when, after a happy passing from this
mortal condition into a better state, the gods shall have made
you capable of knowing it. '

At this moment Theodorus awoke, gave thanks to the god-
dess, and praised the justice of Jupiter, Inspired by what he
had seen and heard, he continued in his office of high priest
with all the zeal of a true servant of his god, and with all the
joy of which mortal man is capable. It appears to me that

MISCELLANEOUS EXTRACTS 267

this continuation of the story throws light on the difficulty
on which Valla did not wish to touch. If Apollo adequately
represented the divine science of vision (which is concerned
with existences), I hope that Pallas has represented well
enough what is called the science of pure intelligence (which
is concerned with everything that is possible), in which one
must finally seek the source of things.

INDEX

INDEX OF PROPER NAMES

ACADEMIC, 109, 113, 126, 190

Academy, the: a philosophical school founded by Plato. Its

members are referred to in these pages as the Academics,

49, 5i

Adam, xii-xiii, xx, 58-61, 64-66, 68, 251, 262
Albert the Great (11931280): a Dominican monk, theologian,

philosopher, and alchemist, 99
Altdorf, vii

Apollo: Greek god, 259, 260-2, 267
Aquinas, Thomas (c. 1227-74) : * ne greatest theologian of the

Western Church. Author of Summa Theologiae, 54, 65, 99
Archimedes (c. 287-212 B.C.) : the most famous geometer of the
ancient world, with a gift for mechanical inventions, xii, 62,
194, 234, 238, 240-1, 251
Aristotelians, 217
Aristotle (384-322 B.C.) : famous Greek philosopher, pupil of Plato

and tutor of Alexander the Great. He wrote works on

logic, metaphysics, ethics, politics, biology, etc., 48, 98-9,

102. 125, 142-3, 155, 193
Arnauld, Antoine (1612-94): distinguished French theologian,

mathematician, and logician, part-author of the Logique de

Port-Royal. Defended the Jansenists against the Jesuits:

vii, xi-xii, xxxi, 52-87, 97 n., 116, 235
Athens, 263
Atomists, 213
Augustine, Saint (354-430) : the greatest philosopher among the

early fathers. Author of De Civitate Dei and Confessions, 185
Averroists : followers of Averrhoes (i 126-98), an Arab philosopher

and commentator on Aristotle. He maintained the eternity

of matter and the mortality of the individual soul, 156

Bacho, John (d. 1346): better known as Baconthorp, from the
place in Norfolk where he was born. A Carmelite monk
and Schoolman, 99

Bacon, Francis (1560-1626): philosopher and man of affairs.
Generally regarded as the earliest of modern philosophers
in England. Author of the Novum Organum, a famous
work on logic and scientific method, 47, 199

Barbara : a mood of the syllogism, 182-3
U95 271

272 INDEX OF PROPER NAMES

Barbaras, Hermolaus (1454-95) : a learned Italian diplomat and

interpreter of Aristotle, n

Basnage, Jacques (1655-1723) : French Protestant theologian, 241
Bayle, Pierre (1647-1706): author of the famous Dictionnaire

Historique et Critique. He maintained the impossibility of

reconciling faith with reason. Much of Leibniz's Theodicee

is concerned with refuting his arguments, xv, xxxi, 5, 12,

88-96, 118-40, 151, 242, 257
Berkeley, George (1684-1753): Irish bishop and empiricist

philosopher. Author of An Essay towards a New Theory

of Vision and a Treatise concerning the Principles of Human

Knowledge. Referred to by Leibniz as 'the man in

Ireland/ 243
Berlin, viii

Berlin Academy, viii
Bernier, Fra^ois (1625-88): a French traveller, author of

Voyages, an account of a sojourn in the East, 118
Bernouilli, Jacques (1654-1705): a Swiss mathematician, 243
Blainville, 179

Bodeman's Catalogue, 241, 248-57
Boethius, C. (480-524) : a Roman philosopher and statesman,

author of De Consolatione Philosophiae, 267, 260, 262
Bosses, Bartholomaeus des (1668-1728): Jesuit theologian, 243
Bossuet, Jacques Benigne (1627-1704): orator and preacher,

known particularly for his funeral orations; Bishop of

Meaux, 250
Bourget, Louis (1678-1742): a merchant who became a scholar,

with a bent for natural philosophy, 245
Boyle, Robert (1627-1691): the famous Irish chemist and

physicist, who gave his name to Boyle's law of the pressure

of gases, vii, 48
Burnet (or Burnett). Thomas (1635-1715): Scots lawyer and

divine, 243

Caesar, Julius (102-44 B.C.), 128-40

Catellan (or Catalan), Jean de ( 7-1725), Bishop of Vallence,
88-90

Caroline (1683-1737): wife of George II of England. Much
interested in philosophy and literature. Clarke dedicated
to her his edition of his correspondence with Leibniz (1717),

193

Cartesians: followers of Descartes. Leibniz regarded Male-
branche as the most important of these. He does not
regard himself or Spinoza as Cartesians, xiv, xx-xxi, 5, 23,
55, 62-3, 88-96, in, 118, I2I-2, 130-2, 148, 151, 165,
185, 195, 205, 217, 230

Cartesian theory of the quantity of motion, xxxi

Cesar e: a mood of the syllogism, 184

INDEX OF PROPER NAMES 273

Chinese, 175, 179

Christian V (1646-99) : King of Denmark and Norway from

1670 to 1699, 39
Christian faith, 159
Christian Mathematicians, 193
Church, the, 57
Circe: an enchantress in Homer's Odyssey who was able to turn

men into beasts, 257

City of God, 19, 29, 56, 86-7, 107, 155, 236
City of Minds, xi, xxv, 19, 86
Clarke, Samuel (1675-1729): Newton's most famous disciple,

xv, xxi, xxxii, 192-229
Commercium Epistolicum, 116
Copernicus, Nicolas (1473-1543): famous Polish astronomer,

author of De Revolutionibus Orbium Coelestium, in
Cordemoy, Geraud de (d. 1684): a French Cartesian, 103
Corinth, 265-6
Coste, Pierre (1668-1747): French translator and critic, known

especially for his translation of Locke's Essay (1700), 141

Daedalus, 257

Darapti: a mood of the syllogism, 184

Datisi: a mood of the syllogism, 184

De Diaeta, 102

Delphi, 259, 262

Democritus: Greek philosopher born about 81 B.C., 101, 103,
131* i35 165, 193-4

Des Argues, Gaspard (1593-1662) : French mathematician, especi-
ally addicted to the methods of pure geometry, 176

Descartes, Rene" (1596-1650): French philosopher, physicist, and
mathematician. His followers are known as Cartesians.
His chief works are Di scours de la Methode and Meditaiiones
de Pnma Philosophia, vii, xiv, xxi, xxii, n, 18, 47-8, 50-1,
85. 9*-5 103-4. "3-14. 153. 216, 239-42

Dictionnaire Historique et Critique , 5, 13, 118, 126-140, 151

Dijon, 136, 189

Disamis: a mood of the syllogism, 183

Discours de Metaphysique, 53-7, 236

Dogmatists, 189

Dresden, viii

Dutch East India Company, 82

Dynamics, 108, 116, 118, 227

Elector-Archbishop of Mainz, John Philip von SchOnborn, bishop

of Wflrzburg and Worms (elector 1647-73), vii, viii
Emperor of the Moon, 214
Empire, viii
England, viii

274 INDEX OF PROPER NAMES

Epicurean: follower of Epicurus, 134, 136, 157, 207

Epicurus (341-270 B.C.) : a Greek philosopher who taught that

pleasure is the sovereign good, 135, 189, 193-4
Equilibria, De, 194

Essay on the Human Understanding, xvii, 141-91
Euclid (450-380 B.C.) : Greek geometer. His Elements are the

basis of plane geometry, 48, 144, 223, 238
Europe, viii
Eve, xii, 65, 252
Exposition of the New System, xxxi, 97-109

Fates, the, 259

Florence, 217

Fludd, Robert (1574-1637) : sought to promulgate in England
theosophical views like those of Paracelsus (1493-1541), 167

Fontenelle, Bernard le Bovier de (1657-1757): member of the
Academic Fran9aise and from 1687 secretary to the Aca-
de*mie des Sciences. His writings were mainly popu-
larizations of scientific ideas. He pronounced a memorial
oration on Leibniz, viii

Foucher, Simon (1644-1696) : a Canon of Dijon who professed
philosophical scepticism, xxxi, 45-51, 109, 117, 189-90

Galileo (1564-1642) : a famous Italian astronomer, author of
Dialogo dei due massimi sistemi del mondo on the Ptolemaic
and Copernican systems, 47-8, 234, 239-42

Gassendi, Pierre (1592-1655): French philosopher, mathema-
tician, and astronomer, 47, 99, 165, 249-50

Genoa, xxiii, 66

George I (1660-1727): Elector of Hanover; King of England
(1714-27), viii

Germany, 66

Ooclenius, Rudolphus (1547-1628) : German philosopher and poet,
author of Lexicon Philosophicum Graeco-Latinum, 201

Gospel, 236

GOttingen, 77

Great Mogul, 78

Greeks, 144, 264

Guericke, Otto von (1602-86): German physicist. Invented
the pneumatic machine, 216-17

Hanover, viii, 114

Harlequin, 214

Hartsoeker, Nicolas (1656-1725): a Dutch physicist, mainly

concerned with the making of microscopes and telescopes.

His correspondence with Leibniz about the philosophy of

nature is extant, 100, 117, 244

INDEX OF PROPER NAMES 275

Hegel, Gottfried W. F. (1770-1831): German philosopher, xxvii
Hercules : the most famous of the heroes of Greek mythology, 147
Herrenhausen, 204
Hessen Rheinfels, Landgraf Ernst von (1623-93): statesman

and soldier, keenly interested in philosophy. He acted

as go-between in the early stages of Leibniz's correspondence

with Arnauld, 52, 57, 61
Hippocrates (born c. 460 B.C.) : greatest physician of antiquity,

14, 102, 150

Htstoire des Outrages des Savans, 119
Hobbes, Thomas (1588-1679): English philosopher, author of

Leviathan, 193, 242
Holy Writ, 251
Homer: Greek poet of tenth or eleventh century B.C.; reputed

author of the Iliad and the Odysscv, 127
Hume, David (1711-76): English philosopher, author of A

Treatise of Human Nature, vii, xxv, xxvii-xxix
Huygens, Christian (1629-95): Dutch physicist, mathematician,

mechanician, and astronomer, vii, 115, 241, 245

Jansenists, 52

Jesuits, 52

Jesus Christ, 57, 155, 236, 262

John Frederick, Duke of Brunswick (d. 1679) . vni

Journal de Pans, 114, 116

Journal des Savans, 117, 118, 190

Judas, 56, 258, 260

Jupiter: Roman name for Zeus, the king and father of the

gods, 259, 261-3, 265-6
Jupiter: the planet, 86
Jurieu, Pierre (1637-1713): French Protestant theologian,

famous for his polemics with Bossuet, 197

Kant, Immanuel (1724-1804): famous German philosopher,

vii, xxvii-xxix

Kant's Copernican Revolution, xxvii
Kingdom of Heaven, 236

La Loubere, Simon de (1642-1729): he wrote a book on Siam,

where he had lived for three months, 163
Lantin, Jean Baptiste (1620-95) : traveller and scholar, 136
Leeuwenhoek, Antony van (1632-1723): Dutch naturalist. He

made microscopes and demonstrated the circulation of the

blood, 100, 245-6
Leipzig, vii

276 INDEX OF PROPER NAMES

Locke, John (1632-1704): English philosopher, author of Essay
concerning the Human Understanding, xvii-xix, xxv, xxvii-
xxix, 55, 133, 141-91, 192, 243

London, vii, viii

Louis XIV, le Grand (1638-1715): King of France (1643-1715),
vii, 179, 239

Magdeburg, 216

Mahomet (c. 571-632) : founder of Islaraism. Caliph is the title

given to the sovereigns who held spiritual and temporal

power after Mahomet, 50
Maintenon, Fran9oise d'Aubign6 Marquise de (1635-1719):

mistress and afterwards wife of Louis XIV of France, 250
Malebranche, Nicolas de (1638-1715): French metaphysician

and Catholic priest, generally referred to by Leibniz as the

'author of the Recherche de la Verite.' vii, 75, 93-4, 96,

100, 104, 195, 239, 241
Malpighi, Marcello (1628-94): Italian scholar, physiologist and

anatomist, 100

Mathematical Principles of Philosophy and of Nature, 198, 224
Meaux, see Bossuet

Melissus (born c. 470 B.C.) : Greek philosopher, 102
Molyneux, William (1656-98): Irish philosopher and friend of

Locke, 176-7
Monadology, ix, xxxi-xxxii

Nantes, 179

New Essays, xvii, xxvii, xxxi, 14191

Newton, Isaac (1642-1727): English mathematician, physicist,
astronomer, and philosopher; author of Philosophiae Natu-
ralis Principia Mathematica and Optiks, viii, xx, xxxii, 157,
162, 192-229, 243-4

Nouvelles de la Republique des Lettres, 88, 152

Nova Zembla, 144

Nuremberg, vii

Odyssey, 127

Oldenburg, 179

Oldenburg, Henry (1615-77): natural philosopher and man of

letters, vii

Optics, 192, 195, 208, 227
Ovid, 249

Pallas Athene: Greek goddess of war and wisdom, 263-7
Paris, vii, viii, xxiii, 66, 88, 179

Parmenides (born c. 539 B.C.) : Greek philosopher, 102
Patin, Gui (1602-72) : French writer and physician, 249

INDEX OF PROPER NAMES 277

Paul, Saint, 143, 261-2

Pellisson, Paul (1624-93) : French historian, 250

Peripatetics : name given in antiquity to the followers of Aristotle,
e.g. Theophrastus, Eudemus, and others, 131

Phaeacians, 127

Phaedo, Plato's, 55

Philosophical Dictionary, 201

Physical Hypothesis, 136

Plato (429-347 B.C.) : famous Greek philosopher, founder of the
Academy and writer of Dialogues. His most famous work
is The Republic, 48, 51, 55, Si, 142-3, 147, 171, 193

Platonist, in, 131

Pliny, the younger (62 -c. 120): Roman man of letters, 101

Poiret, Pierre (1646-1719): French philosopher, influenced by
the Cartesian method and later converted to mysticism, n

Port-Royal Logic, xii

Princess of Wales, see Caroline

Principles of Nature and of Grace, xxxi

Principles of Physics, 117

Pythagoras (born c. 582 B.C.) : Greek mathematician and philo-
sopher, 193

Quietists : a seventeenth-century religious sect whose best-known
member was Molinos, who believed that Christian perfection
consisted in the love of God and the inaction of the soul, 156

Recherche de la Verite, 93-4, 96, 100, 104, 190

Regis, Pierre (1656-1726) : French physician, exiled by the Edict

of Nantes. He spent the rest of his life practising at

Amsterdam, 100
Roberval, Gilles Personne de (1602-75) : French mathematician,

48

Rohan, Henri, Due de (1579-1638): a French general, 179
Romans, 144
Rome, 262, 266
Rorarius, Girolomo (1485-1556): Italian man of letters, who

upheld the view that animals have rational minds, 5, 13, 126
Royal Society, vii

St. Petersburg, viii

Sarmatia: a vast country of eastern Europe. The power of the

Sarmatians was destroyed by the Goths in the third century

and they were merged with the Slavs, 39
Saturn, the planet, 84, 86
Scaliger, Julius (1484-1558): a Renaissance scholar, author of

DC Causis Linguae Latinac, 143

278 INDEX OF PROPER NAMES

Schoolmen (or Scholastics), Schools, xiv, 4-5, 54, 74, 98-9, 122,

143, 158, 166, 172-3, 183, 201, 233, 251
Senate, the, 129
Sextus Tarquimus (d. 496 B c.) : son of the last King of Rome

His outrage on Lucretia brought about the ruin of the

monarchy, 259-66
Socimans. a sect not believing in the Trinity, founded by the

Italian Protestant Socin (Lelio) (1525-62), 197
Socrates (468-400 B c ) : Greek philosopher, 55
Sophia (1630-1714)- Electress of Hanover, mother of George 1

of England, vn
Sophia Charlotte (1668-1705): daughter of the above, Electress

of Brandenburg, and afterwards Queen of Prussia, a friend

and student of Leibniz, vin
Spinoza, Baruch (1632-77) : Dutch philosopher, author of Elhnti

geometnco ordine demonstrata, vn, xm, 196, 242
Stoics, 30, 143, 220
Styx, 261
Swammcrclam, John (1637-80) Dutch naturalist, 100

Theodicy, xxxii, 56, 193-4, 2C M 2II 2 4 2 2 57-^7

Thomas, Saint, see Aquinas

Thrace, 265-6

Torricelli, Evangehsta (1608-47) : Italian physicist and geometer,

pupil of Galileo, 217
Trinity, the, 159, 250

Ultimate Origination of Things, xxxi, 32-41

Valla, Laurentius (1405-1457): philologist and historian to the

King of Spain, 257-62, 267

Vallismeri, Antonio (1661-1730): Italian naturalist, 245-6
Vienna, viii
Virgil (70-19 B c ): Latin poet, author of the Aeneid, 250

Worcester, Edward Stillingfleet, Bishop of (1635-99): his con-
troversy with Locke originated in the anti-religious use to
which Tolland in Christianity Not Mysterious turned some
of Locke's views, 155, 157, 159, 160-2

Zeno, born beginning of the fifth century B c Greek philosopher,
"5

PHILOSOPHICAL INDEX

AcciDENis, 3, 4, 2i<>, 223
Affinity , 138

Aggregation, ix, xm, xxi-n,
xxv, 3, 32-3, 76-9, So, 82 -3,

117. MO
alff07)T'/)piov, 2O2
Algebra, 233
aXXo7\wTricu, 22O
Analysis, xx f xxvin, \xxi, 180-8,

214

Angels, 123, 125, 155, 256, 262
Apperception, x-xi, xviii, 4, 23,

146-8, 151, 153, 168-9, 174-5,

181
Appetition, x, 5-6, 11, 17,

21-2, 99, 137, 180
Arithmetic, xix, xxvu, 27, 45,

144-5, 1 08, HH, 198
Astronomy, 108
Atoms, xxi, 3, 98, 103, 117,

134-7, 148, 152, 165, 172,

209-10, 213
Attraction, 102, 10^
Automatism, automaton, xvi,

xxxi, 6, 15, 22, io(>, 122,

124, 128-34

Body, soul and, xv-xvn, 17, 22,
51, 56, 85, 97, 104-6, no,
114-15, 118, 122, 128, 136,
149, 151, 159, 176, 105, 207,
227

Bomtas extnnseca, 243

Bourgeois, 83

Brain, 195

Brutes, xi, xxvii, 5, 8, 24, 86-7,
100, no, 130-2, 145-6, 155,
163, 165, 169. 174. 257

Calculus, differential, vin

Categories, xxvin

Centres of force, xxii

Chiaroscuio, 178

Cohesion, 157

Colour, 81, 244

Conatus, 130

Conception, 17-18, 25, 240

Contingency, xx, 9, n, 26, 04,

68-9, 71, 182, 210-11, 251
Continuity, law of, xvn-xix,

152, 150

Continuum, 76, So, 98
Contradiction, principle of, x,

xx, 8, 182-3, IC >3 211, 251
Conversions, 183-4
Currency, 243

Demonstrative knowledge, 24,

1 86, 188-9, 235
Determinism, xn, xxvi-xxvn
Deus ex machma, 104, 115, 121,

123

Development, 41
Differential calculus, viii
Dogmatism, xxvm-xxix
Dreams, 83, 105, 121, 189-91
Duration, 220, 223, 228
Dynamics, xin-xv, xxiv, xxvi,

xxxii, 194

*K0e<m, 221
Elective choice, 56
Elements, xxi, 214, 240
Energy, 135. 138-9
Entelechy, 5-6, n, 14-16, 99
Equilibrium, xiv

279

280

PHILOSOPHICAL INDEX

Eternal truths, 8, 10-11, 24,
33. 36, 46. 62, 72, 144, 170,

234. 2 57
Ether, 91, 203
Ethics, xxv
Extension, xiv, xxi-xxiv, 3, 55,

80, 95-6, 98, 109, 117, 125-6,

161, 202, 205, 214, 216, 218,

228

Faculty, 129, 135, 158, 166-7,

i?3. iSi

Faith, 250

Fanatics, 30

Fatalism, 201

Finite material universe, 224

Fluid, 81, 117, 156

Force, xiii-xv, xxi-xxiv, xxv,
27, 88-96, 98-0, 106, 111-16,
126, 133-4, J 94 202 > 208,
226-7

Freedom, xii, xv-xvi, xxy-
xxvi, xxxii, 58, 61, 64, 69,
71, 106-7, 250-2, 257-67

Genus, 161, 164

Geomancy, 236

Geometry, vii, xix, xxvi-xxvii,
24, 27, 32, 35-7, 45, 48, 55,
70, 76, 92, 144, 168, 178, 182,
187-8, 190-1, 194, 198, 206,
215, 223, 236, 251, 264

Grace, 19, 29, 166, 193, 235

Gravity, xxii, 35, 91, 123, 157,
16*, 218

Habit, xviii, 8, 170-1, 252

History, 48

Hypothetical necessity, 33, 58,

60
propositions, 45-6

Identical propositions, xx, 9,

45, 79, 182-5
Identity, 150
of indiscernibles, 204, 206,

213-14

Idols, 199, 202, 206

Immediacy, of ideas, 185

of sensation, 185

Immediate experience, 190
Immortality, xvi, 24, 56, 154-6

160, 163, 1 66, 239
Impenetrability, xxi
Incomplete notions, xiii, 172,

213, 216
Indiscernibles, identity of, 204,

206, 213-14

Individuation, principle of, 215
Induction, 143, 170, 187
Inertia, xxi
Innate ideas, xix, xxix, 146,

1 68

knowledge, 169

principles, 144, 167

truths, 1 68, 171

Insensible perceptions, 152, 154
Intellect, xxviii, 173
Intelhgentia mundana, 197

supramundana, 1978, 202

Interaction, xii-xv, xxii, xxv

xxvi

Intrinsic denomination, 172
Introspection, xxix
Intuitive knowledge, 181-6,

188-9
Invention, 187, 196

Judgment, 175-6, 187
Jurisprudence, 144
Justice, 86, 258

Kinetic energy, xiv
Knowledge, demonstrative, 24,
186, 188-9, 235

innate, 1 69

intuitive, 181-6, 188-9

sensitive, 188-9

Koival {vvotai, 143

Laws of motion, 27, 37, 251

of nature, 193, 202, 208

Logarithms, 225

PHILOSOPHICAL INDEX

281

Logic, viii, xi, xvii, xix-xx,
xxiv-xxv, xxvh-xxviii, xxxi,
24, 27, 182-91

Lymph, 84-5

Machine, xi, xiv, xxxi, 5, 14,
18, 22, 40, 79, 81, 88, 98,
roi-3, iof>, 121, 124-5, 127,
129-33, I 4. I( > 2 . T 96, 203,
208, 236, 241

Magnetic rays, 217

Martyrs, 30

Mass, xx-xxn, 22, 89, 103, 1 06,
109-11, 217

Material universe, finite, 224-5

Materialism, 55, 131,193,196,198

Mathematical points, xxi

principles of philosophy,

193, 198

Matter, 26, 96, 103, 140, 153,
201, 217, 248

all interconnected, 14, 156
an incomplete being, 135

-cannot think, 159-60,

' r >5-7

essentially an aggregate,

117
- geometrical laws of, 37

- gravitation of, 157, 162
infinitely divided, 15, 156

- - natural laws of, in
not capable of perception,

131
not eternal and necessary,

216, 226

not passive, xxi

quantity of, 194, 209-10,

216
sometimes without weight,

218

Maxims, 188
Mean science, 56
Mechanics, xiv, xxvi, 35, 55,

74, 80, 98, 108, 129, 165,

229, 241

metaphysical, 35

Mechanism, 180
Medicine, 241

Metamorphosis, ib, 25, 138
Metaphor, 176
Metaphysical mechanics, 35

points, xxi-xxii

principles of philosophy.

193
Metaphysics, vm, 25, 27, 36,

45. 55. 74. 7 ( >. < So L 92, 95,
98, 104, 107-8, 121, 144,
161-2, 194, 204, 213, 215,

*35* 2 4
Metempsychosis, 16, 25, 100,

155. 222

Method of exclusions, 187
Metonymy, 176
Microscope, 50, 204, 240
Mind, 30, 99, 167, 174

and body, 112, 116, 161

can give itself thoughts,

finite, 209

._^ nature of, xv--xx, xxiv

not a tabula rasa, xxvi-

xxix, 168-70

perfection of, 234-5

Minds, xxii, 23, 38, 133, 140, 1 59
are unities, 21

are whole parts, 40

city of, xxv, 29, 86-7, roi

107

distinguished from brute

souls, x-xi, 8, 1 8, 24, 28-9,

86-7, 99-100

each a world apart, 107

individual, xxv

Miracle, xvi, 53, 63-4, 99, 105.

116, 122-3, I2 7. T 5 8 l6 3.

165-6, 193, 198, 203, 218
Modality, 103
Mode, 8 1
Monad, ix-xi, xxiii-xxiv, xxvii

3-20, 21-3, 28, 151, 214
Moral laws, 229
Morals, 144, 160-1, 166, 251
Motion, laws of, 27, 37, 251

perpetual, 192

quantity of, xiv, 55, 88,

96, 113, 118, 227

282

PHILOSOPHICAL INDEX

Motive, 210-12
Music, 30, 39, 223

Natural, and supernatural,

202- 3

hght, 1 08

Necessary truths, xix, xxvii, 8,

n, 24, 72, 143-0, 168-70,

182, 234
Necessity, formal, 37

hypothetical, 33, 58, 60

material, 37

mechanistic, xxv

metaphysical, 33, 35-6,

210-11

moral, xxvi, 210-1 1

physical, 35

Occult qualities, 163-4
Optics, 178, 191

Perception, 5, 103, 131, 137-
40, 146, 173, 174-81, 188

arid apperception, x, xviii,

4-5, 23, 148, 175

natural, 84

of agreement and disagree-
ment, 191

Perceptions, 8, n, 15, 21, 126

confused, 23 -4, 28, 85,

123, 138-40

conscious, xi, 5-7

distinct, 12, 28

internal, 105-0

minute, 1 50

of animals, 24

unconscious, 5-7, 148-9

Perfectihabiae, n

Perfection, metaphysical, 38

moral, 38

physical, 38

Perspective, 13, 175

Petitio principi i, 171, 213

Phenomena, xvii, 22, 46, 53,
55, 68, 74, 76-82, 105, 108,
ii2, 1 20-1, 126, 167 181,
190-1, 243

Physics, vn, xiii-xv, xx-xxiv,
xxvi, xxxii, 25, 41, 45, 55,
76, 81, 92, 108, 136, 152-3,
i 6 1-2, 240-1

Planets, 218

Plenum, xxiii, 4, 14, 22, So,
156, 210

Pneumatics, 152-3

Politics, 153, 251

Possibility, xxvin, 62-4, 66, Og

Potency, xiv-xv, 37, 173

Predestination, xxvi, xxxii

Pre-established haimony, xv,
xxv-xxvi, 17-18, 22, 20,
113-15, 128, 151, 190

order, 193

Preformation, 16, 24

Probability, 189

Prolepses, 143

Psychology, xvii-xix, xxvii,
xxix, xxxi

Punctum saliens, 245

Quantity of motion, xiv, 55,
88-<}6, 113, 118, 227

Rationalism, xx, xxviii-xxix

Reductio ad absurdum, xn, 198
Reflection, 8, 24, 146, 148-9,

173-4, 181, 248
Religion, 160-1, 166, 258

Christian, 40

natural, 192

Reminiscence, Platonic theory

of, 147, 171
Resuscitation, 101
Revelation, 29, 166

Sagacity, 186-7
Sceptics, 126, 163
Self, the, xiii, xxiv, 8, 24
Self-consciousness, 163
Semina aeternitatis, 143
Sensitive knowledge, 1 88-9
Sensorium, 195, 201-2
Sin, 258

philosophical and theo-
logical, 252-3

PHILOSOPHICAL INDEX

283

Sophisms, 176, 210

Soul, 23, 77, 84. 90, 144, 148,

152, 153, 156, 188, 202
a dominant entelechy, 16,

28

- a little world, 171-2

and body, xv xvii, 17, 22,

5i 5^. S 5t 97. 104-0, no,
114-15, 118, 122, 128, 130,

149, 151. 159. *7 tJ . *95. 207.
227

a substantial form, 7(1

a true unity, 103

- everything which has per-
ceptions and apperceptions, (>
immateriality of, 159-00,
1 66, 192

never separate, 154

only God can hurt, 237
-- represents the universe,

U

- simple and indivisible, ix,

195
Souls, 7, 15

brute, x-xi, 5, 24, 100-1

considered as automata,

119-40

entelechies, 99

natural laws in, in, 114

rational, 8, 24, 28, 155

Space, xxii-xxiv, xxxii, 4, 14,

126, 135, 152, 161-2, 172,

192, 194-5, 199-210, 215-28
Species, xii, 62, 70, 72, 84, 105,

no, 113, 158, 172
Spontaneity, xxvm, 105, 120-1
Subject and predicate, xii--xin,

xvii, xxv-xxvi, 67, 71-3
Substance, xxxi, 3, 4, 83, 126,

146, 152, 205, 235
general idea in both body

and mind, 161

God, 10, 257

immaterial, 131, 103-4,

219

- material, 163-4, 166
nature of, xi-xiii, xiv, xv,

XXV, 21

Substance of the soul, 130, 139,

140
primary, 26

spiritual, 160, 103

Substances, 6, 49, 54, 77, mo,

202

all inter-connected, 84-5

communication of, 07,
105-6, 108-12, 115-10, 120 3,

J 32- 3
individual, xin, xv, 53,

06, 70

no interaction, 104

real unities, xxiv, 71)- 80

represent the universe, 13,

17. 150

simple, 17, 22, 99
Substantial forms, 76-8, 80, 99,

1 10

terms, 80

Sufficient reason, principle of,

x, xx, xxvii-xxix, 8, 25, 32,

194, 198, 200, 204, 209,

211-13, 251

Superhuman spirits, 10, 29, 50
Supernatural, 203, 208, 227
Syllogism, xx, xxxn, 182-5
Synthesis, xxvni, 187

Tabula rasa, x\vi-xxix, 55, 143,

147, 169, 172-3

Theology, natural, 144, 194, 225
Time, xxn-xxiv, xxxii, 14, 126,

161, 172, 199200, 206, 208-9,

215-16, 220, 223-8, 257
Traces, 63, 123, 223
Traction, of atoms, 157
Transcendental method, xxvii
Transformations, 100-1
Transient activity, 112
Transmigration, 101
Truths, contingent, 34

essential, 33

eternal, 33, 72, 170, 234

innate, 168, 171

metaphysical, 33

necessary, xix, xxvii, 168-

70, 182, 234

284

PHILOSOPHICAL INDEX

Truths of experience, 170
of fact, xx, xxviii, 9, 62,

72, 182, 185, 191
of reason, xx, xxviii, 9,

182, 185, 191
primary, 185

universal, xix,

xxviii, 170, 181

Understanding, xxviii, 146, 170
Universe, finite, 224

Vacuum, xxiii, 157, 217, 220,

239
Velocity, xviii, 90-6, 108, 119,

221, 226

Vis viva, xxi-xxiii
Vision, 31, 68, 175, 267
Void, 98, 121, 152, 156, 172,

201, 208,210,214,216-17, 228

Will, the, 211 See Freedom
Zopyra, 143

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Audubon tbe Naturalist, Life and Adventures of. By R. Buchanan. 601
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Thomas. 868

Beaconsfleld (Lord), Life of. By J. A. Fronde. 6CC
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Plato's Dialogues. 2 vols. Introduction by A. D. Lindsay. 456-7
L Republic. Translated, with an Introduction, by A. D. Lindsay. 64
Plutarch's Moralia. 20 Essays translated by Philemon Holland. 665
Sophocles' Dramas. Translated by Sir G. Young, Bart. 114
Tbuoydides' Peloponncsian War. Crawley's Translation. 455
L Virgil's jEneid. Translated by E. Fairfax -Taylor. 161

Eclogues and Georgics. Translated by T. F. Royds, M.A. 222
Xenophon's Cyropeedia. Translation revised by Miss F. M. Stawell. 672

ESSAYS AND BELLES-LETTRES

L Anthology of Prose. Compiled and Edited by Miss S. L. Edwards. 075
Arnold's (Matthew) Essays. Introduction by G. K. Chesterton. 115
Study of Celtic Literature, and other Critical Essays,

with Supplement by Lord Strangford, etc. 4*5 8
(See also POETRY)
L Bacon's Essays. Introduction by Oliphant Smeaton. 10

(See alto PHILOSOPHY)

Bagehot's Literary Studies. 2 vols. Intro, by George Sampson. 620-1
L Brown's Rab and his Friends, etc. 116

Bnrke's Reflections on the French Revolution and contingent Essays
Introduction by A. J. Grieve, M.A. 460 {See afeoORA
3

ESSAYS AND BELLES-LETTRES continued

Canton's (William) The Invisible Playmate, W. V., Her Book, and In
(Sfce also FOB YOUNG PEOPLE) [Memory of W. V. 566

Carlyle's Essays. 2 vols. With Notes by J. Russell Lowell. 703-4

Past and Present. Introduction by R. W. Emerson. 608
Sartor Resartna and Heroes and Hero Worship. 273

(See also BIOGRAPHY and HISTORY)

Castigli one's The Courtier. Translated by Sir Thomas Hoby. Intro-
duction by W. H. D. Boose. 807

Century of Essay*, A. An Anthology of English Essayists. 653
Chesterfield's (Lord) Letters to his Son. 823
L Chesterton's (G. K.) Stories, Essays, and Poems. 913

Coleridge's Biographla Literaria. Introduction by Arthur Symons. 11
Essays and Lectures on Shakespeare, etc. 162

(See also POKTRY)

De la Mare's (Walter) Stories, Essays, and Poems 940 (Ready Spring 1938)

De Qninoey's (Thomas) Opium Eater. Intro, by Sir G. Douglas. 223

The English Mall Coach and Other Writings.

Introduction by S. Hill Burton. 609
(See also BIOGRAPHY)

Dryden's Dramatic Essays. With an Introduction by W. H. Hudson. 568
Elyot's Oouernour. Intro, and Glossary by Prof. Foster Watson. 227
L Emerson's Essays. First and Second Series. 12
L ,, Nature, Conduct of Life, Essays from the 'Dial.* 322

Representative Men. Introduction by E. Rhys. 279
Society and Solitude and Other Essays. 567

(See also POETRY)

Florio's Montaigne. Introduction by A. R. Waller, M.A. 3 vols. 440-2
Froude's Short Studies. Vols. I and II. 13, 705

(See also HISTORY and BIOGRAPHY)

Gilflllan's Literary Portraits. Intro, by Sir W. Robertson Niooll. 343
Goethe's Conversations with Eokermann. Intro, by Havolock Ellis.

851. (See also FICTION and POETRY)
Goldsmith's Citizen of the World and The Bee. Intro, by R. Church. 902

(See also FICTION and POETRY)
Hamilton's The Federalist. 519

Hazlitt's Lectures on the English Oomio Writers. 411
Shakespeare's Characters. 65

Spirit of the Age and Lectures on English Poeta. 459
Table Talk. 321

Plain Speaker. Introduction by P. P. Howe. 814
L Holmes* Autocrat of the Breakfast Table. 66
Poet at the Breakfast Table. 68
,, Professor at the Breakfast Table. 67
L Hudson's (W. H.) A Shepherd's Life. Introduction by Ernest Rhys. 926

Hunt's (Leigh) Selected Essays. Introduction by J. B. Priestley. 29
i, Huxley's (Aldous) Stories, Essays, and Poems. 935
Jrving*s Sketch Book of Geoffrey Crayon. 117

(See also BIOGRAPHY and HISTORY)
Lander's Imaginary Conversations and Poems: A selection. Edited

with Introduction by Havelock Ellis. 890
L Lamb's Essays of Ella. Introduction by Augustine Birrell. 14

(See also BIOGRAPHY and FOR YOUNG PEOPLE)
Lowell's (James Russell) Among My Books. 607

Macaulay's Essays. 2 vole. Introduction by A. J. Grieve, M.A. 225-6
Miscellaneous Essays and The Lays of Ancient Rome. 439

(See also HISTORY and ORATORY)
Machiavelli'B Prince. Special Trans, and Intro, by W. K. Marriott. 280

(See also HISTORY)

Martinengo-Cesaresco (Countess) : Essays in the Study of Folk-Songs* 673
Mazzini'e Duties of Man, etc. Introduction by Thomas Jones, M.A. 224
Milton's Areopagitica, etc. Introduction by Professor O. E. Vaughan. 795

(See also POBTRY)

L Mltford's Our Village. Edited, with Introduction, by Sir John Squire. 927
Montagu's (Lady) Letters. Introduction by R. Brfmley Johnson. 69
Newman's On the Scope and Nature of University Education, and a
paper on Christianity and Scientific Investigation. Introduction by
(See also PHILOSOPHY) [Wilfred Ward. 723

Osborne's (Dorothy) Letters to Sir William Temple. Edited and con-
notated by Judge Parry. 674

Penn's The Peace of Europe. Some Fruits of Solitude, etc. 724
Prelude to Poetry, The. Edited by Ernest Rhys. 789

' Discourses. Introduction by L. March Phillip pa. 119
4

ESSAYS AND BELLES-LETTRES continued

i. Rhys's New Book of Sense and Nonsense. 813

Rousseau's Emile. Translated by Barbara Foxley. 518

(See also PHILOSOPHY AND THEOLOGY)

L Ruskin's Crown of Wild Olive and Cestus of Aglaia. 323
Elements of Drawing and Perspective. 217
Ethics of the Dust. Introduction by Grace Rhys. 282
Modern Painters. 5 vols. Introduction by Lionel Gust. 208-12
Pre-RaphaeUtism. Lectures on Architecture and Painting,
Academy Notes, 1855-9, and Notes on the Turner Gallery.
Introduction by Laurence Bin yon. 218
L Sesame and Lilies, The Two Paths, and The King of the Golden

River. Introduction by Sir Oliver Lodge. 219
., Seven Lamps of Architecture. Intro, by Selwyn Image. 207
Stones of Venice. 3 vols. Intro, by L. March Phillipps. 213-15
Time and Tide with other Essays. 450

Unto This Last, The Political Economy of Art. 216
(See also FOR YOUNG PEOPLE)

Spectator, The. 4 vols. Introduction by G. Gregory Smith. 164-7
Spencer's (Herbert) Essays on Education. Intro, by O. W. Eliot. 504
Sterne's Sentimental Journey and Journal and Letters to Eliza. Intro.
(See also FICTION) [by George Salntsbury. 796

L Stevenson's In the South Seas and Island Nights' Entertainments. 769
L Yirginibus Puerisque and Familiar Studies of Men and

(See also FICTION, POETRY, and TRAVEL) [Books. 765

Swift's Tale of a Tub, The Battle of the Books, etc. 347

(See also BIOGRAPHY and FOR YOUNO PEOPLE)
Table Talk. Edited by J. O. Thornton. 906

Taylor's (Isaac) Words and Places, or Etymological Illustrations of
History, Ethnology, and Geography. Intro, by Edward Thomas. 517
Thackeray's (W. M.) The English Humourists and The Four Georges.
Introduction by Walter Jerrold. 010

(See also FICTION)
L Thoreau's Walden. Introduction by Walter Raymond. 281

Trench's On the Study of Words and English Past and Present. Intro-
duction by George Sampson. 788
Tytlor's Essay on the Principles of Translation. 168
Walton's Compleat Angler. Introduction by Andrew Lang. 70

FICTION

Aimard's The Indian Scout. 428

L Ainsworth's (Harrison) Old St. Paul's. Intro, by W. E. A. Axon. 522
The Admirable Crichton. Intro, by E. Rhys. 804

L ,. The Tower of London. 400

Windsor Castle. 709

Rookwood. Intro, by Frank Swinnerton. 870

American Short Stories of the Nineteenth Century. Edited by John

Cournos. 840
L Austen's (Jane) Emma. Introduction by R. B. Johnson. 24

Mansfield Park. Introduction by R. B. Johnson. 23

L Northanger Abbey and Persuasion. Introduction by

R. B. Johnson. 25_ _ --,..

. B. Johnson. 22

Pride and Prejudice. Introduction by B
Sense and Sensibility. Intro, by R. B.

Johnson. 21

Balzac's (Honore de) Atheist's Mass. Preface by George Saintsbury. 229
.. Catherine de Medici. Introduction by George

Saintsbury. 419
M Christ in Flanders. Introduction by George

Salntsbury. 284

Cousin Pons. Intro, by George Saintsbury. 463
Eugenie Grandet. Intro, by George Saintsbury. 169
Lost Illusions. Intro, by George Saintsbury. 656
Old Goriot. Introduction by George Salntsbury. 170
The Cat and Racket, and Other Stories. 349
The Chouans. Intro, by George Saintsbury. 285
The Country Doctor. Intro. George Saintsbury. 530
, The Country Parson. 686
The Quest of the Absolute. Introduction by George

Saintsbury. 286

The Rise and Fall of Cesar Birotteau. 596
The Wild Ass's Skin. Intro, by George Saintsbury. 26
Ursula Mirouet. Intro, by George Saintsbury. 739

FICTION continued

Barbusse's Under Fire. Translated by Fitcwater Wray. 798
L Bennett's (Arnold) The Old Wives' Tale. 919
L Blackmore's (R. D.) Lorna Doone. 304

L Borrow'a Lavengro. Introduction by Thomas Secoombe. 119
L Romany Rye. 120 (See also TRAVEL)
L Bronte's (Anne) The Tenant of Wildfell Hall and Agnes Grey. 685
L (Charlotte) Jane Byre. Introduction by May Sinclair. 287
L ,. Shirley. Introduction by May Sinclair. 288

The Professor. Introduction by May Sinclair. 417

L , Villette. Introduction by May Sinclair. 351

L (Emily) Wuthering Heights. 243

Burney's (Fanny) Evelina. Introduction by R. B. Johnson. 352
Butler** (Samuel) Erewhon and Erewhon Revisited. Introduction by

Desmond MacCarthy. 881
The Way of All Flesh, introduction by A. J. Hoppe. 895

, ) The Woman in White. 464

L Conrad's Lord Jim. Introduction by R. B. Cunninghame Graham. 925
L Converse's (Florence) Long Will. 328

Dana's (Richard H.) TwoYears before the Mast. 588
Daudet's Tartarin of Tarascon and Tartarin of the Alps. 423
Defoe's Fortunes and Misfortunes of Moll Flanders. Intro, by G. A. Aitken.
Captain Singleton. Introduction by Edward Garnett. 74 [837
Journal of the Plague Year. Introduction by G. A. Aitken. 289
Memoirs of a Cavalier. Introduction by G. A. Aitken. 283

(See also FOR YOUNQ PEOPLE)
CHARLES DICKENS' WORKS. Bach volume with an Introduction by G. K.

Chesterton.

L American Notes. 290 L Little Dorrit. 293

L Barnaby Rudge. 76 L Martin Chuzzlewit. 241

L Bleak House. 236 L Nicholas Nickleby. 238

L Child's History of England. 291 L Old Curiosity Shop. 173
L Christmas Books. 239 L Oliver Twist. 233

L Christmas Stories. 414 L Our Mutual Friend. 294

L, David Copperfield. 242 L Pickwick Papers. 235

s, Dombey and SOD. 240 Reprinted Pieces. 744

Edwin Drood. 725 Sketches by Boz. 237

& Great Expectations. 234 L Tale of Two Cities. 102

Hard Times. 292 L Uncommercial Traveller. 536

Disraeli's Coningsby. Introduction by Langdon Davies. 535
Dobtoev sky's (Fyodor) Crime and Punishment. Introduction by

Laurence Irving. 501
Letters from the Underworld and Other Tales.

Translated by O. J. Hogarth. 654
.. Poor Folk and The Gambler. Translated by C. J.

Hogarth. 711

The Possessed. Introduction by J. Mlddleton

Murry. 2 vols. 861-2 f533

Prison Life In Siberia. Intro. by Madame Stepniak.

The Brothers Karamazov. Translated by Con-

stance Garnett. 2 vote. 802-3
The Idiot. 682
Du Maurier's (George) Trilby. Introduction by Sir Gerald du Maurier.

With the original illustrations. 863

Dumas' Black. Tulip. Introduction by Ernest Rhys. 174
Chicot the Jester. 421

Le Chevalier de Maison Rouge. Intro, by Julius Bramont. 614
Marguerite de Valois ('La Reine Margot'). 326
The Count of Monte Criato. 2 vols. 393-4
The Forty-Five. 420
The Three Musketeers. 81
The Vicomte de Bragelonne. 3 vols. 593-5
Twenty Years After. Introduction by Ernest Rhys. 175
Edgar's Cressy and Poictiers. Introduction by Ernest Rhys. 17
Runnymede and Lincoln Fair. Intro, by L. K. Hughes. 320

(See also FOR YOUNQ PEOPLE)

Edgeworth's Castle Rackrent and The Absentee. 410
I. Eliot's (George) Adam Bede. 27
Felix Holt. 353
Middlemarch. 2 vols. 854-5

L Mill on the Floss. Intro. Sir W. Robertson Nicoll. 326

L Romola. Introduction by Rudolf Dircks. 231

L ,. Scenes of Clerical Life. 468

6

FICTION continued

F.liot's (George) Silas Marner. Introduction by Annie Matheaon. 121
I, English Short Stories. An Anthology. 743

Erclunann-Chatrian's The Conscript and Waterloo. 354

,, The Story of a Peasant. Translated by O. J

Hogarth. 2 vols. 706-7
Fenimore Cooper's The Doorslayer. 77

The Liant of the Mohicans. 79

I, ., The Pathfinder. 78

,. The Pioneers. 171

The Prairie. 172

Ferrior's (Susan) Marriage. Introduction by H. L. Morrow. 816
Fielding's Amelia. Intro, by George Saintsbury. 2 vols. 852-3

Jonathan Wild, and The Journal of a Voyage to Lisbon.

Introduction by George Saintsbury. 877

Joseph Andrews. Introduction by George Saintsbury. 467
.. Tom Jones. Intro, by George Saintsbury. 2 vols. 355-6
Flaubert's Madame Bovary. Translated by Eleanor Marx-Aveliug.

Introduction by George Saintabury. 808
Salammbo. Translated by J. S. Chartres. Introduction by

Professor F. C. Green. 869
French Short Stories of the 19th and 20th Centuries. Selected, with

an Introduction by Professor F. C. Green. 896
L Galsworthy's (John) The Country House. 917

Gait's Annals of a Parish. Introduction by Baillie Macdonald. 427
GaskelTs (Mrs) Cousin Phillis, etc. Intro, by Thos. Seccombe. 615
I, ,. Cranford. 83

Mary Barton. Introduction by Thomas Seccombe. 598
North and South. 680

Sylvia's Lovers. Intro, by Mrs Elite Chadwick. 624

Gleig's (G. R.) The Subaltern. 708
Goethe's Wilhelxn Meister. Carlyle's Translation. 2 vols. 599-600

(.SVe also ESSAYS and POETRT)
Gogol's (Nlcol) Dead Souls. Translated bv O. J. Hogarth. 726

Tares Bulba and Other Tales. 740
L Goldsmith's Vicar of Wakefleld. Introduction by J. M. D. 295

(See also ESSAYS and POETRY)

Goncharov's Oblomov. Translated by Natalie Duddington. 878
Gorki's Through Russia. Translated by C. J. Hogarth. 741
Harte's (Bret) Luck of Roaring Camp and other Tales. 681
Hawthorne's The House of the Seven Gables. Intro, by Ernest Rhys. 176
L ,. The Scarlet Letter. 122

The Blithedalo Romance. 592

The Marble Faun. Intro, by Sir Leslie Stephen. 424
I, Twice Told Tales. 531

(See also FOR YOUNG PEOPLE)

JL Hugo's (Victor) Les Miserables. Intro, by S. R. John. 2 vols. 363-4
L Notre Dame. Introduction by A. C. Swinburne. 422

Toilers of the Sea. Introduction by Ernest Rhys. 509

Italian Short Stories. Edited by D. PettoeUo. 876
James's (G. P. R.) Richelieu. Introduction by Rudolf Dircks. 357
L James's (Henry) The Turn of the Screw and The Aspern Papers. 912

Kingsley's (Charles) Alton Locke. 462

L. Hereward the Wake. Intro, by Ernest Rhys. 29tt

i, ,, Hypatia. 230

L ,. Westward Ho 1 Introduction by A. G. Grieve. 20

Yeast. 611

(See also POETRY and FOB YOUNG PEOPLE)
(Henry) Geoffrey Hamlyn. 416
Ravenshoe. 28

L Lawrence's (D. H.) The White Peacock. 914

Lever's Harry Lorrequer. Introduction by Lewis Melville. 177
L Loti's (Pierre) Iceland Fisherman. Translated by W. P. Balnea. 920
L Lover's Handy Andy. Introduction by Ernest Rhys. 178
L Lytton's Harold. Introduction by Ernest Rhys. 15
L ., Last Days of Pompeii. 80

.. Last of the Barons. Introduction by R. G. Watkin. 18
Rienzi. Introduction by E. H. Blakeney, M.A. 532
(See also TRAVEL)
MacDonald's (George) Sir Gibble. 678

(See also ROMAKOB) [(Mrs Hinkson). 374

Manning's Mary Powell and Deborah's Diary. Intro, by Katherine Tynan
., Sir Thomas More. Introduction by Ernest Rhys. 19

FICTION continued

Marryat's Jacob Faithful. 618

L ,, Mr Midshipman Easy* Introduction by R. B. Johnson. 82
Percival Keene. Introduction by R. Brimley Johnnon. 358
M Peter Simple Introduction by R. Brixnley Johnson. 232
The mug's Own. 680
(See also FOR YOUNG PEOPLE)
L Maugham's (Somerset) Cakes and Ale. 932

Maupassant's Short Stories. Translated by Marjorle Laurie. Intro-
duction by Gerald Gould. 907

Melville's (Herman) Moby Dick. Introduction by Ernest Rhys. 179
Omoo. Introduction by Ernost Rhys. 297

Typee. Introduction by JErm-st If bys. 180

L Meredith's (George) The Ordeal of Richard Feverol. 016

Merixnee's Carmen, with Provost's Manon Lescaut. Introduction by

Philip Henderson. 834
Mlckiewicjs's (Adam) Pan Tadense. 842
L Moore's (George) Esther Waters. 933

Mulock's John Halifax, Gentleman. Introduction by J. Shaylor. 1 23

Neale's (J. M.) The Fall of Constaninqple. 655

Paltook's (Robert) Peter Wilkins; or. The Flying Indians. Introduction

by A. H. Sullen. 676

Pater's Marina the Epicurean. Introduction by Osbert Burdett. 903
Peacock's Headlong Hall and Nightmare Abbey. 327
li Poe's Tales of Mystery and Imagination. Intro, by Padraio Colum. 338

(See alto POETRY)
Provost's Manon Lescaut, with Merimee's Carmen. Introduction by

Philip Henderson. 834
L Priestley's Angel Pavement. 938

Pushkin's (Alexander) The Captain's Daughter and Other Tales. Trans.

by Natalie Duddtngton. 898

QuiUer-Couch's (Sir Arthur) Hetty Wesley. 864 [2 vote. 865-6

Radcliffe's (Ann) Mysteries of Udolpho. Intro, by R. Austin Freeman.

L Reade's (O.) The Cloister and the Hearth. Intro, by A. C. Swinburne. 29

Reade's (O.) Peg Wofflngton and Christie Jobnstone. 299

Richardson's (Samuel) Pamela. Intro, by G. Saintsbury. 2 vols. 683-4

Clarissa. Intro, by Prof. W. L. Pbelps. 4 vois.

882-5

Russian Authors, Short Stories from. Trans, by R. S. Townsond. 768
Sand's (George) The Devil's Pool and Francois the Waif. 634
Scbeffel's Kkkohard: a Tale of the Tenth Century. 629
Scott's (Michael) Tom Cringle's Log. 710
SIB WALTER SCOTT'S WORKS:

Abbot, The. 124 L Ivanhoe. Intro, by Ernest Rhys. l

Anne of Geierstein. 125 L. Kenilworth. 135

I. Antiquary. The. 126 L Monastery. The. 136

Black Dwarf and Legend of Old Mortality. 137

Montrose. 128 Peveril of the Peak. 133

Bride of Lammermoor. 129 Pirate, The. 139

Castle Dangerous and The Snr- Quentin Durward. 140

geon's Daughter. 130 x. Redgauntlet. 141

Count Robert of Paris. 131 x, Rob Roy. 1 42

L Fair Maid of Perth. 132 St. Ronan'a Well. 143

Fortunes of Nigel. 71 Talisman. The. 144

L Guy Mannering. 133 L Waverley. 76

L Heart of Midlothian, The. 134 L Woodstock. Intro, by Edward
Highland Widow and Betrothed. 127 Garnett. 72

(See, also BIOGRAPHY and POETRY)
Shchedrln'B The Golovlyov Family. Translated by Natalie Duddington.

Introduction by Edward Garnett. 908
Shelley's (Mary Wollstoneoaaft) Frankenstein. 616
Sheppard's Charles Auohester. Intro, by Jessie M. Middjeton. 506
Bienktewicz (Henryk). Tales from. Edited by Monica M. Gardner. 871
Shorter Novels, Vol. I. Elizabethan and Jacobean. Edited by Philip

Vol.*!!. Jacobean and Restoration. Edited by Philip

Henderson. 841

Vol. III. Eighteenth Century (Beokford's Vathek,

Walpole's Castle of Otranto, and Dr. Johnson's

Smollett's Peregrine Pickle. 2 vole. 838-9 JRamelAs). 866

Roderick Random. Introduction by H. W. Hodges. 790
L Sterne's Tristram Shandy. Introduction by George SainUbury. 617
(See alto ESSAYS)

S

FICTION continued

L Stevenson's Dr JekyU and Mr Hyde. The Merry Men, and Other Tales
L The Master of Ballantrae and The Black Arrow. 764 [767

L Treasure Inland and Kidnapped. 763

St Ives. Introduction by Ernest Rhys. 904

(See also ESSAYS. POETRY, and TRAVEL)
Surtees* .Tarrocks' Jaunta and Jollities. 817

L Tales of Detection. Edited, with Introduction, by DorothyL. Sayen. 928
Thackeray's Rose and the Rinr and other stories. Intro. by Walter Jerrold.
L Esmond. Introduction by Walter Jerrold. 73 [369

Newcomes. Introduction by Walter Jerrold. 2 vols. 466-6

Pendennis. Intro, by Walter Jerrold. 2 vols. 426-6

Roundabout Papers. 687

L Vanity Fair. Introduction by Hon. Whitelaw Reid. 298

Virginians. Introduction by Walter Jerrold. 2 role. 607-8

(See also ESSAYS)

L Tolstoy's Anna Karenina. Trans, by Rochelle 8. Townsend. 2 rota. 612-13
Childhood, Boyhood, and Youth. Trans, by C. J. Hogarth. 501
Master and Man, and other Parables and Tales. 469
., War and Peace. 3 vote. 525-7
Trollope's (Anthony) Barcheeter Towers. SO
Dr. Thome. 360

Framley Parsonage. Intro, by Ernest Rhys. 181

The Golden Lion of Oranpere. Introduction by

Sir Hugh Walpole. 761

Chronicle of Barset.

.

M The Last Chronicle of Barset. 2 vole. 391-2

Phineas Finn. Intro, by Sir Hugh Walpole. 2 role,

The Small House at Afflngton. 361 1832-3

The Warden. Introduction by Ernest Rhys. 182
Turgenev'H Fathers and Sons. Translated by O. J. Hogarth. 742

. . . .

Liza. Translated by W. R. S. Ralston. 677

^Virgin Soil. _ Translated by Rochelle S. Townsend. 628
E Wes's"(H:^7rThe^mie"Maohineand The Wheels of Chance. 915

Voltaire's Candide and Other Tales. _ _ _
: Walpole's (Hugh) Mr Perrin and Mr Traill.

. . .

Whyte-Melville's The Gladiators. Introduction by J. Mavrogordato. 623
Wood's (Mrs Henry) The Channinga. 84
Yonge's (Charlotte M.) The Dove in the Eagle's Nest. 329

The Heir of Redclyffe. Intro. Mrs Meynell. 362

(See also FOR YOUNG PEOPLE)

Zola's (Exnile) Germinal. Tanslated by Havelook Ellis. 897
HISTORY

Anglo-Saxon Chronicle. The. Translated by James Ingram. 624
Bede's Ecclesiastical History, etc. Introduction by Vida D. Soudder. 479
Burnet's History of His Own Times. 85
L Carlyle's French Revolution. Introduction by H. Belloo. 2 vols. 31-2

(See alto BIOORAPHY and ESSAYS)

L Creasy's Decisive Battles of the World. Introduction by E. Rhys. 300
De JoinriUe (See Villehardouin)

Duruy's (Jean Victor) A History of France. 2 vols. 737-8
Finlay*s Byzantine Empire. 33

Greece under the Romans. 185

Fronde's Henry VIII. Intro, by Llewellyn Williams, M.P. 3 vols. 372-4
Edward VI. Intro, by Llewellyn Williams. M.P.. B.O.L. 376
Mary Tudor. Intro, by Llewellyn Williams, M.P., B.O.L. 477
History of Queen Elizabeth's Reign. 5 vols. Completing

Fronde's 'History of England,' in fo vols. 683-7
(See also ESSAYS and BIOGRAPHY)

Gibbon's Decline and Fall of the Roman Empire. Edited, with Introduc-
tion and Notes, by Oliphant Smeaton, M.A. 6 vols. 434-6, 474-6

(See also BIOGRAPHY)

Green's Short History of the English People. Edited and Revised by
L. Cecil Jane, with an Appendix by R. P. Farley, B.A. 2 vols. 727-8
Grote's History of Greece. Intro, by A. D. Lindsay. 12 vols. 186-97
Hallam's (Henry) Constitutional History of England. 3 vols. 621-3
Holinshed's Chronicle as used in Shakespeare's Plays. Introduction by

Professor Allardyce Nicoll. 800
Irvine's (Washington) Conquest of Granada. 478

(See alto ESSAYS and BIOGRAPHY)

Josephus* Wars of the Jews. Introduction by Dr Jacob Hart. 712
L Maca olay's History of England. 3 vols. 34-6
(See also ESSAYS and ORATORY)
9

HISTORY continued

Maine's (Sir Henry) Ancient Law. 734

Merivale's History of Home. (An Introductory vol. to Gibbon.) 433

Mignet's <F. A. M.) The French Revolution. 713

Milman's History of the Jews. 2 Tola. 377-8

Mommsen's History of Rome. Translated by W. P. Dick&on, LL.D.

With a review of the work by E. A. Freeman. 4 vote. 542-5
L Motley's Dutch Republic. 3 vote. 86-8

Parkman's Conspiracy of Pontlao. 2 vole. 302-3

Paston Letters, The. Based on edition of Knight. Introduction by

Mrs Archer-Hind, M.A. 2 vols. 752-3

Pilgrim Fathers, The. Introduction by John Maaefleld. 480
L Pinnow's History of Germany. Translated by M. R. Brailsford. 929
Political Liberty, The Growth of. A Source-Book of English History.

Arranged by Ernest Rhys. 745

Prescott'a Conquest of Mexico. With Introduction by Thomas Secoombe,
M.A. 2 vols. 397-8

,. Conquest of Pern. Intro, by Thomas Secoombe, M.A. 301
Slsmondi's Italian Republics. 250

Stanley's Lectures on the Eastern Church. Intro, by A. J. Grieve. 251
Tacitus. Vol. I. Annals. Introduction by E. H. Blakeney. 273

m Vol. II. Agrlcola and Germania. Intro, by E. H. Blakeney. 274
Thierry's Norman Conquest. Intro, by J. A. Price, B.A. 2 vols. 198-9
Villehardouin and De Join vl lie's Chronicles of the Crusades. Translated,

with Introduction, by Sir F. Marzials, C.B. 333
Voltaire's Age of Louis XIV. Translated by Martyn P. Pollack. 780

ORATORY

L Anthology of British Historical Speeches and Orations. Compiled by

Ernest Rhys. 714

Bright's (John) Speeches. Selected with Intro, by Joseph Sturge. 252
Burke's American Speeches and Letters. 340

(See also ESSAYS)

Demosthenes: Select Orations. 646
Fox (Charles James): Speeches (French Revolutionary War Period).

Edited with Introduction by Irene Cooper Willis, M.A. 759
Lincoln's Speeches, etc. Intro, by the Rt. Hon. James Bryce. 206

(See also BIOGRAPHY)
Macaulay's Speeches on Politics and Literature. 399

(See also ESSAYS and HISTORY)
Pitt's Orations on the War with France. 145

PHILOSOPHY AND THEOLOGY

L A Kempls' Imitation of Christ. 484

Ancient Hebrew Literature. Being the Old Testament and Apocrypha.

Arranged by the Rev. R. B. Taylor. 4 vols. 253-6
Aristotle, The Nlcomachean Ethics of. Translated by D. P. Chase.

Introduction by Professor J. A. Smith. 547

(See also CLASSICAL)
Bacon's The Advancement of Learning. 719

(See also ESSAYS)
Berkeley's (Bishop) Principles of Human Knowledge, New Theory of

Vision. With Introduction by A. D. Lindsay. 483
Boehme's (Jacob) The Signature of All Things, with Other Writings.

Introduction by Clifford Bax. 569

Browne's Religio Medici, etc. Introduction by Professor O. H. Herford. 92
Bunyan's Grace Abounding and Mr Badman. Introduction by G. B.

Harrison. 815 (See also ROMANCE)

Burton's (Robert) Anatomy of Melancholy. Introduction by Holbrook

Jackson. 3 vols. 886-8

Butler's Analogy of Religion. Introduction by Rev. Ronald Bayne. 90
Descartes' (Rene) A Discourse on Method. Translated by Professor John

Veitch. Introduction by A. D. Lindsay. 570

L Ellis' (Havelock) Selected Essays. Introduction by J. S. Collie. 930
I, Gore's (Charles) The Philosophy of the Good Life. 924

Hobbes' Leviathan. Edited, with Intro, by A. D. Lindsay, M.A. 691
Hooker's Ecclesiastical Polity. Intro, by Rev. H. Bayne. 2 vols. 201-2
Hume's Treatise of Human Nature, and other Philosophical Works.

Introduction by A. D. Lindsay, M.A. 2 vols. 548-9
James (William): Selected Papers on Philosophy. 739
Kant's Critique of Pure Reason. Translated by J. M. D. Melklejohn.

Introduction by A. D. Lindsay, M.A. 909

PHILOSOPHY AND THEOLOGY continued

Keble's The Christian Tear. Introduction by J. O. Shairp. 690
King Edward VI. First and Second Prayer Books. Introduction by th

Right Rev. Bishop of Gloucester. 448
L Koran, The. Rodwell's Translation. 380

Latimer's Sermons. Introduction by Canon Beaching. 40

Law's Serious Call to a Devout and Holy Life. 91

Leibniz's Philosophical Writings. Selected and trans, by Mary Morris.

Introduction by C. R. Morris, M.A. 905
Locke's Two Treatises of Girl) Government. Introduction by Professor

William S. Carpenter. 751

Malthus on the Principles of Population. 2 vols. 692-3
Mill's (John Stuart) Utilitarianism, Liberty, Representative Government.

With Introduction by A. D. Lindsay, M.A. 482

v Subjection of Women. (See Wollstonecraft, Mary, under SCIENCE.)
More's Utopia. Introduction by Judge O'Hagan. 461
L New Testament. Arranged in the order in which the books came to the

Christians of the First Century. 93
Newman's Apologia, pro Vita Sua. Intro, by Dr Charles Sarolea. 836

(See also ESSAYS)
Nietzsche's Thus Spake Zarathustra. Translated by A. Tille and

M. M. Bozman. 892

Paine's Rights of Man. Introduction by G. J. Holyoake. 718
Pascal's Pensees. Translated by W. F. Trotter. Introduction by

T. S. Eliot. 874 [C.I.B. 403

Haxuayana and the Mahabharata, The. Translated by Roinesh Dutt,
Kenan's Life of Jesus. Introduction by Right Rev. Chas. Gore, D.D. 806

Robertson's (F. W.) Sermons on Religion and Life, Christian Doctrine,
and Bible Subjects. Ea " ' ---.--

Burnett. 3 vols. 37-9

and Bible Subjects. Each Volume with Introduction by Canon

Robinson's (Wade) The Philosophy of Atonement and Other Sermons.

Introduction by Rev. F. B. Meyer. 637

Rousseau's (J. J.) The Social Contract, etc. 660 (See also ESSAYS)
St Augustine's Confessions. Dr Pusey's Translation. 200
L St Francis: The Little Flowers, and The Life of St Francis. 485
Seeley's Ecoe Homo. Introduction by Sir Oliver Lodge. 305
Spinoza's Ethics, etc. Translated by Andrew J. Boyle. With Intro-
duction by Professor Santayana. 481
Swedenborg's (Emmanuel) Heaven and Hell. 379

The Divine Love and Wisdom. 635

The Divine Providence. 658

L ., ., The True Christian Religion. 893

POETRY AND DRAMA

Anglo-Saxon Poetry. Edited by Professor R. K. Gordon. 794
Arnold's (Matthew) Poems, 1840-66, including Thyrsis. 334
Ballads, A Rook of British. Selected by R. B. Johnson. 572
Beaumont and Fletcher, The Select Plays of. Introduction by Professor

Baker, of Harvard University. 506

Bjttrnson's Plays. Vol. I. The Newly Married Couple, Leonardo, A

Gauntlet. Trans, by R. Farqubarson Sharp. 625

Vol. II. The Editor, The Bankrupt, and The King.

Translated by R. Earquharsou Sharp. 69(5

Blake's Poems and Prophecies. Introduction by Max Plowman. 792
z. Browning's Poems, 1833-44. Introduction by Arthur Waugfc, 41
I, Browning's Poems. 1844-64. 42

The Ring and the Book. Intro, by Chas. W. Hoaell. 502

L Burns' Poems and Songs. Introduction by J. Douglas. 94
Byron's Poetical and Dramatic Works. 3 vols. 480-8
Calderon: Six Plays, translated by Edward FltzGerald. 819
L Chaucer's Canterbury Tales. Edited by Principal BurreU, M.A. 307
ColerMge, Golden Book of. Edited by Stopford A. Brooko. 43

(See also ESSAYS)
Cowper (William). Poems of. Edited by H. I'Anson Fausset. 872

(See also BIOGRAPHY)
L Dante's Divine Comedy (Gary's Translation). Specially edited by

Edmund Gardner. 308

Donne's Poems. Edited by H. I'Anson Fausset. 867
Dryden's Poems. Edited by Bonamy Dobree. 910
Eighteenth-Century Plays. Edited by John Hampden. 818
Emerson's Poems. Introduction by Professor Bakewell, Yale, U.S.A. 716
L Knffllnh Religious Verse. Edited by G. Lacey May. 937

II

POETRY AND DRAMA continued

Everyman and other Interludes, including eight Miracle Plays. Edited

by Ernest Rhys. 381

L FtteGerald's (Edward) Omar Khayyam and Six Plays of Calderon. 810

L Goethe's Faust. Parts I and II. Trans, and Intro, by A. O. Latham. 335

(See. also ESSA.YB and FICTION) [well. 921

L Golden Book of Modern English Poetry, The. Edited by Thomas Cald-

Golden Treasury of Longer Poems, The. Edited by Ernest Rhys. 746

Goldsmith's Poems and Plays. Introduction by Austin Dobson. 415

{See also ESSAYS and FICTION)

Gray's Poems and Letters. Introduction by John Drlnkwater. 028
Hebbel's Plays. Translated with an Introduction by Dr O. K. Allen. 694
Heine: Prose and Poetry. 911

Herbert's Temple. Introduction by Edward Thomas. 309
Herrick's Hesporides and Noble Numbers. Intro, by Ernest Rhys. 310
L Ibsen's Brand. Translated by F. E. Garrett. 716
L Ghosts, The Warriors at Helgoland, and An Enemy of the People.

Translated by R. Farquharson Sharp. 552
L Lady Inger of Ostraat, Lore's Comedy, and The League of

Youth. Translated by R. Farquharson Sharp. 729
Peer Gynt. Translated by R. Farquharson Sharp. 747
L , A Doll's House, The Wild Duck, and The Lady from the Sea,

Translated by R. Farquharson Sharp. 494
The Pretenders, Pillar* of Society, and Rosmersholm. Translated

by R. Farquharson Sharp. B59

Jonson's (Ben) Plays. Introduction by Professor SchelJing. 2 vols. 489 -90
Kalldaea: Shakuntala. Translated by Professor A. W. Ryder. 629
L Keats' Poems. 101

Kingsley's (Charles) Poems. Introduction by Ernest Rhys. 793

(fief also FICTION and FOB YOUNO PBOPLE)
L Lanpland's (William) Piers Plowman. 571

Lessinff's LaocoOn, Minna von Barnhelm, and Nathan the Wise. 843
L Longfellow's Poems. Introduction by Katherina Tynan. 382

Marlowe's Plays and Poems. Introduction by Edward Thomas. 383
L Milton's Poems. Introduction by W. H. D. Rouse. 384

(See also ESSAYS)
Minor Elizabethan Drama. Vol. I. Tragedy. Selected, with Introduction.

by Professor Thorndike. Vol. II. Comedy. 491-2
L Minor Poets of the 18th Century. Edited by H. I'Anson Fausset. 844

Minor Poets of the 17th Century. Edited by R. G. Howarth. 873
L Modern Plays. 942

Moliere's Comedies. Introduction by Prof. F. O. Green. 2 vole. 830-1
L New Golden Treasury, The. An Anthology of Songs and Lyrics. 695

Old Yellow Book, The. Introduction by Charles E. Hodell. 503
L Omar Khayyam (The Rubalyat of). Trans, by Edward FltrGerald. 819
L Palsrrave's Golden Treasury. Introduction by Edward Hutton. 96
Percy's Reliques of Ancient English Poetry. 2 vols. 148-9
Poe's (Edgar Allan) Poems and Essays. Intro, by Andrew Lang. < 91

(See also FICTION)

Pope (Alexander) : Collected Poems. Introduction by Ernest Rhys. 760
Procter's (Adelaide A.) Legends and Lyrics. 150

Restoration Plays, A Volume of. Introduction by Edmund Gosse. 604
L Rossetti's Poems and Translations. Introduction by E. G. Gardner. 627
Scott's Poems and Plays. Intro, by Andrew Lang. 2 vols. 550-1

(See also BIOGRAPHY and FICTION)
L Shakespeare's Comedies. 153

Historical Plays, Poems, and Sonnets. 154
Tragedies. 165

Poetical Works. Introduction by A. H. Koszul. 3 vols. 257-8
n's Plays. 95

Faerie Queene. Intro, by Prof. J. W. Hales. 2 vote. 443-4
Shepherd's Calendar and Other Poems. Edited by Philip

Henderson. 879
Stevenson's Poems-A Child's Garden of Verses, Underwoods, SOUKS of

Travel, Ballads. 768 (See also ESSAYS, FICTION, and TRAVEL)
i. Tchekhov. Plays and Stories. 941

Tennyson's Poems. Vol. I, 1830-56. Introduction by Ernest Rhys. 44
,, Vol. if, 1857-70. 626 [Harrison. 899

Webster and Ford. Plays. Selected, with Introduction, by Dr. G. B.
Whitman's (Walt) Leaves of Grass (I), Democratic Vistas, etc. 673
Wilde (Oscar), Plays, Prose Writings and Poems. 858
L Wordsworth's Shorter Poems. Introduction by Ernest Rhys. 203
M Longer Poems. Note by Editor. 311

12

REFERENCE

Atlas of Ancient and Classical Geography. Many coloured and line

Maps; Historical Gazetteer, Index, etc. 451
Biographical Dictionary of English Literature. 449
Biographical Dictionary of Foreign Literature. 900
Dates, Dictionary of. 554

Dictionary of Quotations and Proverbs. 2 vols. 809-10
Everyman's English Dictionary. 776
Literary and Historical Atlas. I. Europe. Many coloured and line MA ps ;

full Index and Gazetteer. 496

,, ,, II. America. Do. 553

III. Asia. Do. 633

,, IV. Africa and Australia. Do. 662

Non-Classical Mytholocry, Dictionary of. 632
Reader's Guide to Everyman's Library. By R. Farquharson Sharp.

Introduction by Ernest Rhys. 889

' Roget's Thesaurus of English Words and Phrases. 2 vols. 630-1
Smith's Smaller Classical Dictionary. Revised and Edited by E. H.

Blakaney, M.A. 495
Wright's An Encyclopaedia of Gardening. 555

ROMANCE

Aucassin and Nicolette, with other Medieval Romances. 497
Boccaccio's Decameron. (Unabridged.) Translated by J. M. Risir.

Introduction by Edward Hutton. 2 vols, 845-6
L Banyan's Pilflfrim's Progress. Introduction by Rev. H. E. Lewis. 204

Burnt Njal, The Story of. Translated by Sir George Dasent. 558
L Cervantes' Don Quixote. Motteux's Translation. Lockhart's Intro-
duction. 2 vols. 385-6
Chretien de Troves: Eric and Enid. Translated, with Introduction and

Notes, by William Wistar Comfort. 698

French Medieval Romances. Translated by Eugene Mason. 557
Geoffrey of Monmouth's Histories of the Kings of Britain. 577
Grettir Saga, The. Newly Translated by G. Alnslie Might. 699
Gudrun. Done into English by Margaret Armour. 880
Guest's (Lady) Mabinogion. Introduction by Rev. R. Williams. 97
Beimskringla: The Olaf Sagas. Translated by Samuel Laing. Intro-
duction and Notes by John Beveridge. 717
Sagas of the Norse Kings. Translated: by Samuel Laing.

Introduction and Notes by John Boverldge. 847
Holy Graal, The High History of the. 445

Kalevala. Introduction by W. F. Kirby, F.L.S., F.E.S. 2 vols. 259-60
Le Sage's The Adventures of Gil Bias. Intro, by Anatole Lo Bras. 2 vols.
MacDonald's (George) P ban tastes: A Faerie Romance. 732 [437-8

(See also FICTION)

Malory's Le Morte d' Arthur. Intro, by Professor Rhys. 2 vols. 45-6
L Morris (William): Early Romances. Introduction by Alfred Noyes. 261

The Life and Death of Jason. 575

Morte d' Arthur Romances, Two. Introduction by Luoy A. Paton. 634
Nibelungs, The Fall of the. Translated by Margaret Armour. 312
Rabelais' The Heroic Deeds of Gargantua and Pantagrnel. Introduction

by D. B. Wyndham Lewis. 2 vols. 826-7

Wace's Arthurian Romance. Translated by Eugene Mason* Laya-
mon's Brut. Introduction by Luoy A. Paton. 578

SCIENCE

Boyle's The Sceptical Chymist. 559

Darwin's The Origin of Species. Introduction by Sir Arthur Keith. 811
(See also TRAVEL) [E. F. Bozman. 922

L Eddlngton's (Sir Arthur) The Nature of the Physical World. Intro, by
slid: the Elements of. Todhunter's Edition. Introduction by Sir

""*-, K.O.B. 891

>erimental Researches in Electricity. 576
BLuman Faculty. Revised by Author. 263
.ss and Poverty. 560

5>-e: h on e& tto RaU ^ ** of HeaUn *

Harvey's Circulation of the Blood. Introduction by Ernest Parkyn. 262
Howard's State of the Prisons. Introduction by Kenneth Ruck. 835
Huxley's Essays. Introduction by Sir Oliver Lodge. 47

~ b Lectures and Lay Sermons. Intro. Sir Oliver Lodge. 498

Anton's Voyages. Introduction by John Masefleld. 610

Bates' Naturalist on the Amazon. With Illustrations. 446

Belt's The Naturalist in Nicaragua. Intro, by Anthony Belt, F.L.S. 561

SCIENCE continued

Lyell's Antiquity of Man. With an Introduction by R. H. Rastall. 700
Marx's (Karl) Capital. Translated by Eden and Cedar Paul. Intro-
duction by O. D. H. Cole. 2 vote. 848-9
Miller's Old Red Sandstone. 103
Owen's (Robert) A New View of Society, etc. Intro, by O. D. H. Cole. 799

L Pearson's (Karl) The Grammar of Science. 939

Ricardo's Principles of Political Economy and Taxation. 690
Smith's (Adam) The Wealth of Nations. 2 vols. 412-13
Tyndall's Glaciers of the Alps and Mountaineering in 1861. 98
White's Selborne. Introduction by Principal Windle. 48
Wollstonecraft (Mary), The Rights of Woman, with John Stuart Mill's
The Subjection of Women. 825

TRAVEL AND TOPOGRAPHY

Anson's Voyages. Introduction by John
Bates' Naturalist on the Amazon. With

Belt's The Naturalist In Nicaragua. Intro. _.. ,

Borrow's (George) The Gypsies in Spain. Intro, by Edward Thomas. 697

L ,. The Bible in Spain. Intro, by Edward Thomas. 151

Wild Wales. Intro, by Theodore Watts-Dunton. 49

(See also FICTION)
BoBwell'B Tour in the Hebrides with Dr Johnson. 387

' (See also BIOGRAPHY)

Burton's (Sir Richard) First Footsteps in East Africa. 500
Cobbett's Rural Rides. Introduction by Edward Thomas. 2 vols. 638-9

L Cook's Voyages of Discovery. 99

Oreveeceur's (H. St John) Letters from an American Farmer. 640
Darwin's Voyage of the Beaglo. 104

(See also SCIENCE)

Defoe's Tour Through England and Wales. Introduction by Q. D. H.
(See also FICTION) [Cole. 820-1

Dennis' Cities and Cemeteries of Etniria. 2 vols. 183-4
Dufferin'e (Lord) Letters from High Latitudes. 499
Ford's Gatherings from Spain. Introduction by Thomas Okey. 162
Franklin's Journey to the Polar Sea. Intro, by Cant. R. F. Scott. 447
Giraldufl Cambrensis: Itinerary and Description of Wales. 272
Haklnyt's Voyages. 8 vols. 264, 265, 313. 314, 338, 339. 388, 389
Kinglake's Eothen. Introduction by Harold Spender, M.A. 337
Lane's Modern Egyptians. With many Illustrations. 315
Mandeville's (Sir John) Travels. Introduction by Jules Bramont. 812
Park (Mungo): Travels. Introduction by Ernest Rhys. 205
Peaks, Passes, and Glaciers. Selected by E. H. Blakeney, M.A. 778

L Polo's (Marco) Travels. Introduction by John Masefleld. 306

Roberts' The Western Avernus. Intro, by Cunninghame Graham. 762

Speke's Discovery of the Source of the Nile. 60 _
. Stevenson's An Inland Vo

L Stevenson's An inland Voyage, Travels with a Donkey, and Silverado
Squatters. 766

(See also ESSAYS, FICTION, and POBTBY)

Stow's Survey of London. Introduction by H. B. Wheatley. 589
Wakeneld's Letter from Sydney and Other Writings on Colonization. 828
Waterton's Wanderings in South America. Intro, by E. Selous. 772
Young's Travels in France and Italy. Intro, by Thomas Okey. 720

FOR YOUNG PEOPLE

L JEsop'a and Other Fables: An Anthology from all sources. 65V

Alcott's Little Men. Introduction by Grace Rhys. 512
L ,, Little Women and Good Wives. Intro, by Grace Rhys. 248
Andersen's Fairy Tales. Illustrated by the Brothers Robinson. 4
More Fairy Tales. Illustrated by Mary Shillaboer. 822
Annals of Fairyland. The Reign of King Oberon. 366

The Reign of King Cole. 366

Asgard and the Norse Heroes. Translated by Mrs Boult. 689
Baker's Cast up by the Sea. 539
L Ballantyne's cW Island. 245

Martin Rattler. 246

Ungava. Introduction by Ernest Rhys. 276

L Browne's (Frances) Granny's Wonderful Chair. Introduction by Doble

Radford. 112
Bnlflnoh'B (Thorns*) The Age of Fable. 472

Legends of Charlemagne. Intro, by Ernest Rhys. 556

14

FOR YOUNG PEOPLE continued

L Canton's A Child's Book of Saints. Illustrated by T. H. Robinson. 61

. (See also Ess ATS)

x, Carroll's Alice in Wonderland, Through the Looking-Glass, etc. Illus-
trated by the Author. Introduction by Ernest Rhys. 836
,, Tales from Chaucer. 537

Collodi's Pinocchlo; or, The Story of a Puppet. 538

L Converse's (Florence) The House of Prayer. 023 (See also FICTION)
Cox's (Sir G. W.) Tales of Ancient Greece. 721
Defoe's Robinson Crusoe. Illustrated by J. A. Symington. 59

(See also FICTION)

Dodge's (Mary Mapes) Hans Brinker; or, The Silver Skates. 620
Edgar's Heroes of England. 471

(See also FICTION)
L Swing's (Mrs) Jackanapes, Daddv Darwin's Dovecot, illustrated by

R. Caldecott, and The Story of a Short Life. 731
Mrs Ovortheway'e Remembrances. 730
L Fairy Gold. Illustrated by Herbert Cole. 157
I. Fairy Tales from the Arabian Nights. Illustrated. 249
FroiBHnrfc'fl Chronicles. 57

Gatty's Parables from Nature. Introduction by Grace Rhys. 158
Grimm's Fairy Tales. Illustrated by R. Anning Bell. 56
Hawthorne's Wonder Book and Tanglewood Tales. 5

(See also FICTION)

Howard's Rattlin the Heefer. Introduction by Guy Pocock. 857
L Hughes' Tom Brown's School Days. Illustrated by T. Robinson. 58
Ingelow'e (Jean) Mopsa the Fairy. . Illustrated by Dora Curtis. 619
Jeff erica's (Richard) Bevis, the Story of a Boy. Introduction by Guy

Pocock. 850
L Kingsley's Heroes. Introduction by Grace Rhys. 113

Madam How and Lady Why. Introduction by O. I. Gardiner.

L Water Babies and Glaucus. 277 [M.A. 777

(See also POETKY and FICTION)
Kingston's Peter the Whaler. 6

Three MidHhipmen. 7

L Lamb's Tales from Shakespeare. Illustrated by A. Rackham. 8

(See also BIOGRAPHY and ESSAYS)
L Lear (and Others): A Book of Nonsense. 806
Marryat's Children of the New Forest. 247

Little Savage. Introduction by R. Brimley Johnson. 159
Masterman Ready. Introduction by R. Brimley Johnson. 160
Settlers in Canada. Introduction by R. Brimley Johnson. 370

(Edited by) RattUn the Reefer. 857
(See also FICTION)

Martineau's Feats on the Fjords, etc. Illustrated by A. Rackham. 429
Mother Goose's Nursery Rhymes. Illustrated. 473
Poetry Book for Boys and Girls. Edited by Guy Pooook. 894
Reid's (Mayne) The Boy Hunters of the Mississippi. 582

The Boy Slaves. Introduction by Guy Pocock. 797

Ruskin's The Two Boyhoods and Other Passages. 688

(See also ESSAYS)

L SewelTs (Anna) Black Beauty. Illustrated by Lucy Kemp -Welch. 748
L Spyri's (Johanna) Heidi. Illustrations by Lizzie Lawson. 431
L Story Book for Boys and Girls. Edited by Guy Pocock. 934

Stowe's Uncle Tom's Cabin. 371
L Swift's Gulliver's Travels. Illustrated by A. Rackham. 60

(See also BIOGRAPHY and ES.SAYS)

L Swiss Family Robinson. Illustrations by Chas. Folkard. 430
Verne's (Jules) Abandoned. 60 Illustrations. 368

., Dropped from the Clouds. 50 Illustrations. 367

L Five Weeks in a Balloon and Around the World in Eighty

Days. Translated by Arthur Chambers and P. Dosages.
L Twenty Thousand Leagues Under the Sea. 319 779

The Secret of the Island. 50 Illustrations. 369
Tonge's (Charlotte M.) The Book of Golden Deeds. 330

The Lances of Lynwood. Illustrated by Dora

Curtis. 579

I* ., The Little Duke. Illustrated by Dora Curtis. 47 o

(See also FICTION)

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