Essays on the Goodness of God the Freedom of Man and the Origin of Evil
Edited with an Introduction by Austin Farrer, Fellow of Trinity College, Oxford
Translated by E.M. Huggard from C.J. Gerhardt's Edition of the Collected Philosophical Works, 1875-90
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LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA
Leibniz, Gottfried Wilhelm, Freiherr von, 1646-1716. Theodicy: essays on the goodness of God, the freedom of man, and the origin of evil.
Translation of: Essais de Theodicee. Includes index. 1. Theodicy—Early works to 1800. I. Title. B2590.E5 1985 231'.8 85-8833 ISBN O-87548-437-9
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EDITOR'S INTRODUCTION page 7 PREFACE 49 PRELIMINARY DISSERTATION ON THE CONFORMITY OF FAITH WITH 73 REASON ESSAYS ON THE JUSTICE OF GOD AND THE FREEDOM OF MAN IN THE 123, 182, 276 ORIGIN OF EVIL, IN THREE PARTS APPENDICES SUMMARY OF THE CONTROVERSY, REDUCED TO FORMAL ARGUMENTS 377 EXCURSUS ON THEODICY, Sec. 392 389 REFLEXIONS ON THE WORK THAT MR. HOBBES PUBLISHED IN 393 ENGLISH ON 'FREEDOM, NECESSITY AND CHANCE' OBSERVATIONS ON THE BOOK CONCERNING 'THE ORIGIN OF EVIL', 405 PUBLISHED RECENTLY IN LONDON CAUSA DEI ASSERTA 443 INDEX 445
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Leibniz was above all things a metaphysician. That does not mean that his head was in the clouds, or that the particular sciences lacked interest for him. Not at all—he felt a lively concern for theological debate, he was a mathematician of the first rank, he made original contributions to physics, he gave a realistic attention to moral psychology. But he was incapable of looking at the objects of any special enquiry without seeing them as aspects or parts of one intelligible universe. He strove constantly after system, and the instrument on which his effort relied was the speculative reason. He embodied in an extreme form the spirit of his age. Nothing could be less like the spirit of ours. To many people now alive metaphysics means a body of wild and meaningless assertions resting on spurious argument. A professor of metaphysics may nowadays be held to deal handsomely with the duties of his chair if he is prepared to handle metaphysical statements at all, though it be only for the purpose of getting rid of them, by showing them up as confused forms of something else. A chair in metaphysical philosophy becomes analogous to a chair in tropical diseases: what is taught from it is not the propagation but the cure.
Confidence in metaphysical construction has ebbed and flowed through philosophical history; periods of speculation have been followed by periods of criticism. The tide will flow again, but it has not turned yet, and  such metaphysicians as survive scarcely venture further than to argue a case for the possibility of their art. It would be an embarrassing task to open an approach to Leibnitian metaphysics from the present metaphysical position, if there is a present position. If we want an agreed starting-point, it will have to be historical.
The historical importance of Leibniz's ideas is anyhow unmistakable. If metaphysical thinking is nonsensical, its empire over the human imagination must still be confessed; if it is as chimerical a science as alchemy, it is no less fertile in by-products of importance. And if we are to consider Leibniz historically, we cannot do better than take up his Theodicy, for two reasons. It was the only one of his main philosophical works to be published in his lifetime, so that it was a principal means of his direct influence; the Leibniz his own age knew was the Leibniz of the Theodicy. Then in the second place, the Theodicy itself is peculiarly rich in historical material. It reflects the world of men and books which Leibniz knew; it expresses the theological setting of metaphysical speculation which still predominated in the first years of the eighteenth century.
Leibniz is remembered for his philosophy; he was not a professional philosopher. He was offered academic chairs, but he declined them. He was a gentleman, a person of means, librarian to a reigning prince, and frequently employed in state affairs of trust and importance. The librarian might at any moment become the political secretary, and offer his own contributions to policy. Leibniz was for the greater part of his active life the learned and confidential servant of the House of Brunswick; when the Duke had nothing better to do with him, he set him to research into ducal history. If Leibniz had a profession in literature, it was history rather than philosophy. He was even more closely bound to the interests of his prince than John Locke was to those of the Prince of Orange. The Houses of Orange and of Brunswick were on the same side in the principal contest which divided Europe, the battle between Louis XIV and his enemies. It was a turning-point of the struggle when the Prince of Orange supplanted Louis's Stuart friends on the English throne. It was a continuation of the same movement, when Leibniz's master, George I, succeeded to the same throne, and frustrated the restoration of the Stuart heir. Locke returned to England in the wake of the Prince of Orange, and became the  representative thinker of the regime. Leibniz wished to come to the English court of George I, but was unkindly ordered to attend to the duties of his librarianship. So he remained in Hanover. He was then an old man, and before the tide of favour had turned, he died.
Posterity has reckoned Locke and Leibniz the heads of rival sects, but politically they were on the same side. As against Louis's political absolutism and enforced religious uniformity, both championed religious toleration and the freedom of the mind. Their theological liberalism was political prudence; it was not necessarily for that reason the less personally sincere. They had too much wisdom to meet bigotry with bigotry, or set Protestant intolerance against Catholic absolutism. But they had too much sympathy with the spirit of Europe to react into free thinking or to make a frontal attack on revealed truth. They took their stand on a fundamental Christian theism, the common religion of all good men; they repudiated the negative enormities of Hobbes and Spinoza.
The Christian was to hold a position covered by three lines of defences. The base line was to be the substance of Christian theism and of Christian morals, and it was to be held by the forces of sheer reason, without aid from scriptural revelation. The middle line was laid down by the general sense of Scripture, and the defence of it was this. 'Scriptural doctrine is reconcilable with the findings of sheer reason, but it goes beyond them. We believe the Scriptures, because they are authenticated by marks of supernatural intervention in the circumstances of their origin. We believe them, but reason controls our interpretation of them.' There remained the most forward and the most hazardous line: the special positions which a Church, a sect, or an individual might found upon the scriptural revelation. A prudent man would not hold his advance positions in the same force or defend them with the same obstinacy as either of the lines behind them. He could argue for them, but he could not require assent to them.
One cannot help feeling, indeed, the readiness of these writers to fall back, not only from the front line to the middle line, but from the middle line itself to the base line. Leibniz, for example, writes with perfect seriousness and decency about the Christian scheme of redemption, but it hardly looks like being for him a crucial deliverance from perdition. It is not the intervention of Mercy, by which alone He possesses himself of  us: it is one of the ways in which supreme Benevolence carries out a cosmic policy; and God's benevolence is known by pure reason, and apart from Christian revelation.
In one politically important particular the theological attitude of Leibniz differed from that of Locke. Both stood for toleration and for the minimizing of the differences between the sects. This was a serious enough matter in England, but it was an even more serious matter in Germany. For Germany was divided between Catholics and Protestants; effective toleration must embrace them both. English toleration might indulge a harmless Catholic minority, while rejecting the Catholic regime as the embodiment of intolerance. But this was not practical politics on the Continent; you must tolerate Catholicism on an equal footing, and come to terms with Catholic regimes. Leibniz was not going to damn the Pope with true Protestant fervour. It was his consistent aim to show that his theological principles were as serviceable to Catholic thinkers as to the doctors of his own church. On some points, indeed, he found his most solid support from Catholics; in other places there are hints of a joint Catholic-Lutheran front against Calvinism. But on the whole Leibniz's writings suggest that the important decisions cut across all the Churches, and not between them.
Leibniz was impelled to a compromise with 'popery', not only by the religious divisions of Germany, but (at one stage) by the political weakness of the German Protestant States. At the point of Louis XIV's highest success, the Protestant princes had no hope but in Catholic Austria, and Austria was distracted by Turkish pressure in the rear. Leibniz hoped to relieve the situation by preaching a crusade. Could not the Christian princes sink their differences and unite against the infidel? And could not the Christian alliance be cemented by theological agreement? Hence Leibniz's famous negotiation with Bossuet for a basis of Catholic-Lutheran concord. It was plainly destined to fail; and it was bound to recoil upon its author. How could he be a true Protestant who treated the differences with the Catholics as non-essentials? How could he have touched pitch and taken no defilement? Leibniz was generally admired, but he was not widely trusted. As a mere politician, he may be judged to have over-reached himself.
It has been the object of the preceding paragraphs to show that Leibniz the politician and Leibniz the theologian were one and the same person; not at all to suggest that his rational theology was just political expediency. We may apply to him a parody of his own doctrine, the pre-established harmony between nature and grace. Everything happens as though Leibniz were a liberal politician, and his theology expressed his politics. Yes, but equally, everything happens as though Leibniz were a philosophical theologian, and his politics expressed his theology. His appreciation of Catholic speculation was natural and sincere; his dogmatic ancestry is to be looked for in Thomism and Catholic humanism as much as anywhere. Above all, he had himself a liberal and generous mind. It gave him pleasure to appreciate good wherever he could see it, and to discover a soul of truth in every opinion.
From the moment when Leibniz became aware of himself as an independent thinker, he was the man of a doctrine. Sometimes he called it 'my principles', sometimes 'the new system', sometimes 'pre-established harmony'. It could be quite briefly expressed; he was always ready to oblige his friends with a summary statement, either in a letter or an enclosed memorandum, and several such have come down to us. The doctrine may have been in Leibniz's view simple, but it was applicable to every department of human speculation or enquiry. It provided a new alphabet of philosophical ideas, and everything in heaven and earth could be expressed in it; not only could be, but ought to be, and Leibniz showed tireless energy in working out restatements of standing problems.
As a man with an idea, with a philosophical nostrum, Leibniz may be compared to Bishop Berkeley. There was never any more doubt that Leibniz was a Leibnitian than that Berkeley was a Berkeleian. But there is no comparison between the two men in the width of their range. About many things Berkeley never took the trouble to Berkeleianize. To take the most surprising instance of his neglect—he assured the world that his whole doctrine pointed to, and hung upon, theology. But what sort of a theology? He scarcely took the first steps in the formulation of it. He preferred to keep on defending and explaining his esse est percipi. With Leibniz it is wholly different; he carries his new torch into every corner, to illuminate the dark questions.
The wide applicability of pre-established harmony might come home to its inventor as a rich surprise. The reflective historian will find it less surprising, for he will suspect that the applications were in view from the start. What was Leibniz thinking of when the new principle flashed upon him? What was he not thinking of? He had a many-sided mind. If the origins of the principle were complex, little wonder that its applications were manifold. Every expositor of Leibniz who does not wish to be endlessly tedious must concentrate attention on one aspect of Leibniz's principle, and one source of its origin. We will here give an account of the matter which, we trust, will go most directly to the heart of it, but we will make no claims to sufficient interpretation of Leibniz's thought-processes.
Leibniz, then, like all the philosophers of the seventeenth century, was reforming scholasticism in the light of a new physical science. The science was mathematical in its form, mechanistical in its doctrine, and unanswerable in its evidence—it got results. But it was metaphysically intractable, and the doctrines of infinite and finite substance which it generated furnish a gallery of metaphysical grotesques; unless we are to except Leibniz; his system is, if nothing else, a miracle of ingenuity, and there are moments when we are in danger of believing it.
It is a natural mistake for the student of seventeenth-century thought to underestimate the tenacity of scholastic Aristotelianism. Descartes, we all know, was reared in it, but then Descartes overthrew it; and he had done his work and died by the time that Leibniz was of an age to philosophize at all. We expect to see Leibniz starting on his shoulders and climbing on from there. We are disappointed. Leibniz himself tells us that he was raised in the scholastic teaching. His acquaintance with Descartes's opinions was second-hand, and they were retailed to him only that they might be derided. He agreed, like an amiable youth, with his preceptors.
The next phase of his development gave him a direct knowledge of Cartesian writings, and of other modern books beside, such as those of the atomist Gassendi. He was delighted with what he read, because of its fertility in the field of physics and mathematics; and for a short time he was an enthusiastic modern. But presently he became dissatisfied. The new systems did not go far enough, they were still scientifically inadequate. At the same time they went too far, and carried metaphysical paradox beyond the limits of human credulity.
 There is no mystery about Leibniz's scientific objections to the new philosophers. If he condemned them here, it was on the basis of scientific thought and observation. Descartes's formulation of the laws of motion could, for example, be refuted by physical experiment; and if his general view of physical nature was bound up with it, then so much the worse for the Cartesian philosophy. But whence came Leibniz's more strictly metaphysical objections? Where had he learned that standard of metaphysical adequacy which showed up the inadequacy of the new metaphysicians? His own disciples might be satisfied to reply, that he learnt it from Reason herself; but the answer will not pass with us. Leibniz reasoned, indeed, but he did not reason from nowhere, nor would he have got anywhere if he had. His conception of metaphysical reason was what his early scholastic training had made it.
There are certain absurd opinions which we are sure we have been taught, although, when put to it, we find it hard to name the teacher. Among them is something of this sort. 'Leibniz was a scholarly and sympathetic thinker. He had more sense of history than his contemporaries, and he was instinctively eclectic. He believed he could learn something from each of his great predecessors. We see him reaching back to cull a notion from Plato or from Aristotle; he even found something of use in the scholastics. In particular, he picked out the Aristotelian "entelechy" to stop a gap in the philosophy of his own age.' What this form of statement ignores is that Leibniz was a scholastic: a scholastic endeavouring, like Descartes before him, to revolutionize scholasticism. The word 'entelechy' was, indeed, a piece of antiquity which Leibniz revived, but the thing for which it stood was the most familiar of current scholastic conceptions. 'Entelechy' means active principle of wholeness or completion in an individual thing. Scholasticism was content to talk about it under the name of 'substantial form' or 'formal cause'. But the scholastic interpretation of the idea was hopelessly discredited by the new science, and the scholastic terms shared the discredit of scholastic doctrine. Leibniz wanted a term with a more general sound. 'There is an X', he wanted to say, 'which scholasticism has defined as substantial form, but I am going to give a new definition of it.' Entelechy was a useful name for X, the more so as it had the authority of Aristotle, the master of scholasticism.
Under the name of entelechy Leibniz was upholding the soul of  scholastic doctrine, while retrenching the limbs and outward flourishes. The doctrine of substantial form which he learnt in his youth had had something in it; he could not settle down in the principles of Descartes or of Gassendi, because both ignored this vital something. Since the requirements of a new science would not allow a return to sheer scholasticism, it was necessary to find a fresh philosophy, in which entelechy and mechanism might be accommodated side by side.
If one had asked any 'modern' of the seventeenth century to name the 'ancient' doctrine he most abominated, he would most likely have replied, 'Substantial form'. Let us recall what was rejected under this name, and why.
The medieval account of physical nature had been dominated by what we may call common-sense biology. Biology, indeed, is the science of the living, and the medievals were no more inclined than we are to endow all physical bodies with life. What they did do was to take living bodies as typical, and to treat other bodies as imperfectly analogous to them. Such an approach was a priori reasonable enough. For we may be expected to know best the physical being closest to our own; and we, at any rate, are alive. Why not argue from the better known to the less known, from the nearer to the more remote, interpreting other things by the formula of our own being, and allowing whatever discount is necessary for their degree of unlikeness to us?
Common-sense biology reasons as follows. In a living body there is a certain pattern of organized parts, a certain rhythm of successive motions, and a certain range of characteristic activities. The pattern, the sheer anatomy, is basic; but it cannot long continue to exist (outside a refrigerator) without accompanying vital rhythms in heart, respiration and digestion. Nor do these perform their parts without the intermittent support of variable but still characteristic activities: dogs not only breathe and digest, they run about, hunt their food, look for mates, bark at cats, and so on. The anatomical pattern, the vital rhythm, and the characteristic acts together express dogginess; they reveal the specific form of the dog. They reveal it; exactly what the specific form consisted in was the subject of much medieval speculation. It need not concern us here.
Taking the form of the species for granted, common-sense biology proceeds to ask how it comes to be in a given instance, say in the dog Toby.  Before this dog was born or thought of, his form or species was displayed in each of his parents. And now it looks as though the form of dog had detached itself from them through the generative act, and set up anew on its own account. How does it do that? By getting hold of some materials in which to express itself. At first it takes them from the body of the mother, afterwards it collects them from a wider environment, and what the dog eats becomes the dog.
What, then, is the relation of the assimilated materials to the dog-form which assimilates them? Before assimilation, they have their own form. Before the dog eats the leg of mutton, it has the form given to it by its place in the body of a sheep. What happens to the mutton? Is it without remainder transubstantiated from sheep into dog? It loses all its distinctively sheep-like characteristicsm but there may be some more basically material characteristics which it preserves. They underlay the structure of the mutton, and they continue to underlie the structure of the dog's flesh which supplants it. Whatever these characteristics may be, let us call them common material characteristics, and let us say that they belong to or compose a common material nature.
The common material nature has its own way of existing, and perhaps its own principles of physical action. We may suppose that we know much or that we know little about it. This one thing at least we know, that it is capable of becoming alternatively either mutton or dog's flesh. It is not essential to it to be mutton, or mutton it would always be; nor dog's flesh, or it would always be dog's flesh. It is capable of becoming either, according as it is captured by one or other system of formal organization. So the voters who are to go to the polls are, by their common nature, Englishmen; they are essentially neither Socialist curs nor Conservative sheep, but intrinsically capable of becoming either, if they become captured by either system of party organization.
According to this way of thinking, there is a certain looseness about the relation of the common material nature to the higher forms of organization capable of capturing it. Considered in itself alone, it is perhaps to be seen as governed by absolutely determined laws of its own. It is heavy, then it will fall unless obstructed; it is solid, then it will resist intrusions. But considered as material for organization by higher forms, it is indeterminate. It acts in one sort of way under the persuasion of the sheep-form, and in another sort of way under the persuasion of the  dog-form, and we cannot tell how it will act until we know which form is going to capture it. No amount of study bestowed on the common material nature will enable us to judge how it will behave under the persuasion of the higher organizing form. The only way to discover that is to examine the higher form itself.
Every form, then, will really be the object of a distinct science. The form of the sheep and the form of the dog have much in common, but that merely happens to be so; we cannot depend upon it, or risk inferences from sheep to dog: we must examine each in itself; we shall really need a science of probatology about sheep, and cynology about dogs. Again, the common material nature has its own principles of being and action, so it will need a science of itself, which we may call hylology. Each of these sciences is mistress in her own province; but how many there are, and how puzzlingly they overlap! So long as we remain within the province of a single science, we may be able to think rigorously, everything will be 'tight'. But as soon as we consider border-issues between one province and another, farewell to exactitude: everything will be 'loose'. We can think out hylology till we are blue in the face, but we shall never discover anything about the entry of material elements into higher organizations, or how they behave when they get there. We may form perfect definitions and descriptions of the form of the dog as such, and still derive no rules for telling what elements of matter will enter into the body of a given dog or how they will be placed when they do. All we can be sure of is, that the dog-form will keep itself going in, and by means of, the material it embodies—unless the dog dies. But what happens to the matter in the body of the dog is 'accidental' to the nature of the matter; and the use of this matter, rather than of some other equally suitable, is accidental to the nature of the dog.
No account of material events can dispense with accidental relations altogether. We must at least recognize that there are accidental relations between particular things. Accident in the sense of brute fact had to be acknowledged even by the tidiest and most dogmatic atomism of the last century. That atomism must allow it to be accidental, in this sense, that the space surrounding any given atom was occupied by other atoms in a given manner. It belonged neither to the nature of space to be occupied by just those atoms in just those places, nor to the nature of the atoms to be  distributed just like that over space; and so in a certain sense the environment of any atom was an accidental environment. That is, the particular arrangement of the environment was accidental. The nature of the environment was not accidental at all. It was proper to the nature of the atom to be in interaction with other atoms over a spatial field, and it never encountered in the fellow-denizens of space any other nature but its own. It was not subject to the accident of meeting strange natures, nor of becoming suddenly subject to strange or unequal laws of interaction. All interactions, being with its own kind, were reciprocal and obedient to a single set of calculable laws.
But the medieval philosophy had asserted accidental relations between distinct sorts of natures, the form of living dog and the form of dead matter, for example. No one could know a priori what effect an accidental relation would produce, and all accidental relations between different pairs of natures were different: at the most there was analogy between them. Every different nature had to be separately observed, and when you had observed them all, you could still simply write an inventory of them, you could not hope to rationalize your body of knowledge. Let us narrow the field and consider what this doctrine allows us to know about the wood of a certain kind of tree. We shall begin by observing the impressions it makes on our several senses, and we shall attribute to it a substantial form such as naturally to give rise to these impressions, without, perhaps, being so rash as to claim a knowledge of what this substantial form is. Still we do not know what its capacities of physical action and passion may be. We shall find them out by observing it in relation to different 'natures'. It turns out to be combustible by fire, resistant to water, tractable to the carpenter's tools, intractable to his digestive organs, harmless to ostriches, nourishing to wood-beetles. Each of these capacities of the wood is distinct; we cannot relate them intelligibly to one another, nor deduce them from the assumed fundamental 'woodiness'.
We can now see why 'substantial forms' were the betes noires of the seventeenth-century philosophers. It was because they turned nature into an unmanageable jungle, in which trees, bushes, and parasites of a thousand kinds wildly interlaced. There was nothing for it, if science was to proceed, but to clear the ground and replant with spruce in rows: to postulate a single uniform nature, of which there should be a single science. Now neither probatology nor cynology could hope to be  universal—the world is not all sheep nor all dog: it would have to be hylology; for the world is, in its spatial aspect, all material. Let us say, then, that there is one uniform material nature of things, and that everything else consists in the arrangements of the basic material nature; as the show of towers and mountains in the sunset results simply from an arrangement of vapours. And let us suppose that the interactions of the parts of matter are all like those which we can observe in dead manipulable bodies—in mechanism, in fact. Such was the postulate of the new philosophers, and it yielded them results.
It yielded them results, and that was highly gratifying. But what, meanwhile, had happened to those palpable facts of common experience from which the whole philosophy of substantial forms had taken its rise? Is the wholeness of a living thing the mere resultant of the orderly operations of its parts? Is a bee no more essentially one than a swarm is? Is the life of a living animal indistinguishable from the rhythm of a going watch, except in degree of complication and subtlety of contrivance? And if an animal's body, say my own, is simply an agglomerate of minute interacting material units, and its wholeness is merely accidental and apparent, how is my conscious mind to be adjusted to it? For my consciousness appears to identify itself with that whole vital pattern which used to be called the substantial form. We are now told that the pattern is nothing real or active, but the mere accidental resultant of distinct interacting forces: it does no work, it exercises no influence or control, it is nothing. How then can it be the vehicle and instrument of my conscious soul? It cannot. Then is my soul homeless? Or is it to be identified with the activity and fortunes of a single atomic constituent of my body, a single cog in the animal clockwork? If so, how irrational! For the soul does not experience itself as the soul of one minute part, but as the soul of the body.
Such questions rose thick and fast in the minds of the seventeenth-century philosophers. It will cause us no great surprise that Leibniz should have quickly felt that the Formal Principle of Aristotle and of the Scholastic philosophy must be by hook or by crook reintroduced—not as the detested substantial form, but under a name by which it might hope to smell more sweet, entelechy.
Nothing so tellingly revealed the difficulties of the new philosophy in dealing with living bodies as the insufficiency of the solutions Descartes had proposed. He had boldly declared the unity of animal life to be purely mechanical, and denied that brutes had souls at all, or any sensation. He had to admit soul in man, but he still denied the substantial unity of the human body. It was put together like a watch, it was many things, not one: if Descartes had lived in our time, he would have been delighted to compare it with a telephone system, the nerves taking the place of the wires, and being so arranged that all currents of 'animal spirit' flowing in them converged upon a single unit, a gland at the base of the brain. In this unit, or in the convergence of all the motions upon it, the 'unity' of the body virtually consisted; and the soul was incarnate, not in the plurality of members (for how could it, being one, indwell many things?), but in the single gland.
Even so, the relation between the soul and the gland was absolutely unintelligible, as Descartes disarmingly confessed. Incarnation was all very well in the old philosophy: those who had allowed the interaction of disparate natures throughout the physical world need find no particular difficulty about the special case of it provided by incarnation. Why should not a form of conscious life so interact with what would otherwise be dead matter as to 'indwell' it? But the very principle of the new philosophy disallowed the interaction of disparate natures, because such an interaction did not allow of exact formulation, it was a 'loose' and not a 'tight' relation.
From a purely practical point of view the much derided pineal gland theory would serve. If we could be content to view Descartes as a man who wanted to make the world safe for physical science, then there would be a good deal to be said for his doctrine. In the old philosophy exact science had been frustrated by the hypothesis of loose relations all over the field of nature. Descartes had cleared them from as much of the field as science was then in a position to investigate; he allowed only one such relation to subsist, the one which experience appeared unmistakably to force upon us—that between our own mind and its bodily vehicle. He had exorcized the spirits from the rest of nature; and though there was a spirit here which could not be exorcized, the philosophic conjurer had nevertheless confined it and its unaccountable pranks within a minutely narrow magic circle: all mind could do was to turn the one tiny switch at the centre of its  animal telephone system. It could create no energy—it could merely redirect the currents actually flowing.
Practically this might do, but speculatively it was most disturbing. For if the 'loose relation' had to be admitted in one instance, it was admitted in principle; and one could not get rid of the suspicion that it would turn up elsewhere, and that the banishment of it from every other field represented a convenient pragmatic postulate rather than a solid metaphysical truth. Moreover, the correlation of the unitary soul with the unitary gland might do justice to a mechanistical philosophy, but it did not do justice to the soul's own consciousness of itself. The soul's consciousness is the 'idea' or 'representation' of the life of the whole body, certainly not of the life of the pineal gland nor, as the unreflective nowadays would say, of the brain. I am not conscious in, or of, my brain except when I have a headache; consciousness is in my eyes and finger-tips and so on. It is physically true, no doubt, that consciousness in and of my finger-tips is not possible without the functioning of my brain; but that is a poor reason for locating the consciousness in the brain. The filament of the electric bulb will not be incandescent apart from the functioning of the dynamo; but that is a poor reason for saying that the incandescence is in the dynamo.
Certainly the area of representation in our mind is not simply equivalent to the area of our body. But in so far as the confines of mental representation part company with the confines of the body, it is not that they may contract and fall back upon the pineal gland, but that they may expand and advance over the surrounding world. The mind does not represent its own body merely, it represents the world in so far as the world affects that body or is physically reproduced in it. The mind has no observable natural relation to the pineal gland. It has only two natural relations: to its body as a whole and to its effective environment. What Descartes had really done was to pretend that the soul was related to the pineal gland as it is in fact related to its whole body; and then that it was related to the bodily members as in fact it is related to outer environment. The members became an inner environment, known only in so far as they affected the pineal gland; just as the outer environment in its turn was to be known only in so far as it affected the members.
 This doctrine of a double environment was wholly artificial. It was forced on Descartes by the requirements of mechanistical science: if the members were simply a plurality of things, they must really be parts of environment; the body which the soul indwelt must be a body; presumably, then, the pineal gland. An untenable compromise, surely, between admitting and denying the reality of the soul's incarnation.
What, then, was to be done? Descartes's rivals and successors attempted several solutions, which it would be too long to examine here. They dissatisfied Leibniz and they have certainly no less dissatisfied posterity. It will be enough for us here to consider what Leibniz did. He admitted, to begin with, the psychological fact. The unity of consciousness is the representation of a plurality—the plurality of the members, and through them the plurality of the world. Here, surely, was the very principle the new philosophy needed for the reconciliation of substantial unity with mechanical plurality of parts. For it is directly evident to us that consciousness focuses the plurality of environing things in a unity of representation. This is no philosophical theory, it is a simple fact. Our body, then, as a physical system is a mechanical plurality; as focused in consciousness it is a unity of 'idea'.
Very well: but we have not got far yet. For the old difficulty still remains—it is purely arbitrary, after all, that a unitary consciousness should be attached to, and represent, a mechanical collection of things which happen to interact in a sort of pattern. If there is a consciousness attached to human bodies, then why not to systems of clockwork? If the body is represented as unity, it must surely be because it is unity, as the old philosophy had held. But how can we reintroduce unity into the body without reintroducing substantial form, and destroying the mechanistical plurality which the new science demanded?
It is at this point that Leibniz produces the speculative postulate of his system. Why not reverse the relation, and make the members represent the mind as the mind represents the members? For then the unity of person represented in the mind will become something actual in the members also.
Representation appears to common sense to be a one-way sort of traffic. If my mind represents my bodily members, something happens to my mind, for it becomes a representation of such members in such a state; but nothing happens to the members by their being so represented in the mind. The  mental representation obeys the bodily facts; the bodily facts do not obey the mental representation. It seems nonsense to say that my members obey my mind because they are mirrored in it. And yet my members do obey my mind, or at least common sense supposes so. Sometimes my mind, instead of representing the state my members are in, represents a state which it intends that they shall be in, for example, that my hand should go through the motion of writing these words. And my hand obeys; its action becomes the moving diagram of my thought, my thought is represented or expressed in the manual act. Here the relation of mind and members appears to be reversed: instead of its representing them, they represent it. With this representation it is the opposite of what it was with the other. By the members' being represented in the mind, something happened to the mind, and nothing to the members; by the mind's being represented in the members something happens to the members and nothing to the mind.
Why should not we take this seriously? Why not allow that there is two-way traffic—by one relation the mind represents the members, by another the members represent the mind? But then again, how can we take it seriously? For representation, in the required sense, is a mental act; brute matter can represent nothing, only mind can represent. And the members are brute matter. But are they? How do we know that? By brute matter we understand extended lumps of stuff, interacting with one another mechanically, as do, for example, two cogs in a piece of clockwork. But this is a large-scale view. The cogs are themselves composed of interrelated parts and those parts of others, and so on ad infinitum. Who knows what the ultimate constituents really are? The 'modern' philosophers, certainly, have proposed no hypothesis about them which even looks like making sense. They have supposed that the apparently inert lumps, the cogs, are composed of parts themselves equally inert, and that by subdivision we shall still reach nothing but the inert. But this supposition is in flat contradiction with what physical theory demands. We have to allow the reality of force in physics. Now the force which large-scale bodies display may easily be the block-effect of activity in their minute real constituents. If not, where does it come from? Let it be supposed, then, that these minute real constituents are active because they are alive, because they are minds; for indeed we have no notion of activity other than the perception we have  of our own. We have no notion of it except as something mental. On the hypothesis that the constituents of active body are also mental, this limitation in our conception of activity need cause us neither sorrow nor surprise.
The mind-units which make up body will not of course be developed and fully conscious minds like yours or mine, and it is only for want of a better word that we call them minds at all. They will be mere unselfconscious representations of their physical environment, as it might be seen from the physical point to which they belong by a human mind paying no attention at all to its own seeing. How many of these rudimentary 'minds' will there be in my body? As many as you like—as many as it is possible there should be—say an infinite number and have done with it.
We may now observe how this hypothesis introduces real formal unity without prejudicing mechanical plurality. Each of the mind-units in my body is itself and substantially distinct. But since each, in its own way and according to its own position, represents the superior and more developed mind which I call 'me', they will order themselves according to a common form. The order is real, not accidental: it is like the order of troops on a parade-ground. Each man is a distinct active unit, but each is really expressing by his action the mind of the officer in command. He is expressing no less his relation to the other men in the ranks—to obey the officer is to keep in step with them. So the metaphysical units of the body, being all minds, represent one another as well as the dominant mind: one another co-ordinately, the dominant mind subordinately.
But if the metaphysically real units of the body are of the nature of mind, then the mind is a mind among minds, a spirit-atom among spirit-atoms. What then constitutes its superiority or dominance, and makes it a mind par excellence? Well, what constitutes the officer an officer? Two things: a more developed mentality and the fact of being obeyed. In military life these two factors are not always perfectly proportioned to one another, but in the order of Leibniz's universe they are. A fuller power to represent the universe is necessarily combined with dominance over an organized troop of members; for the mind knows the universe only in so far as the universe is expressed in its body. That is what the  finitude of the mind means. Only an infinite mind appreciates the whole plurality of things in themselves; a finite mind perceives them in so far as mirrored in the physical being of an organized body of members. The more adequate the mirror, the more adequate the representation: the more highly organized the body, the more developed the mind.
The developed mind has an elaborate body; but the least developed mind has still some body, or it would lack any mirror whatever through which to represent the world. This means, in effect, that Leibniz's system is not an unmitigated spiritual atomism. For though the spiritual atoms, or monads, are the ultimate constituents out of which nature is composed, they stand composed together from the beginning in a minimal order which cannot be broken up. Each monad, if it is to be anything at all, must be a continuing finite representation of the universe, and to be that it must have a body, that is to say, it must have other monads in a permanent relation of mutual correspondence with it. And if you said to Leibniz, 'But surely any physical body can be broken up, and this must mean the dissolution of the organic relation between its monadical constituents,' he would take refuge in the infinitesimal. The wonders revealed by that new miracle, the microscope, suggested what the intrinsic divisibility of space itself suggests—whatever organization is broken up, there will still be a minute organization within each of the fragments which remains unbroken—and so ad infinitum. You will never come down to loose monads, monads out of all organization. You will never disembody the monads, and so remove their representative power; you will only reduce their bodies and so impoverish their representative power. In this sense no animal dies and no animal is generated. Death is the reduction and generation the enrichment of some existing monad's body; and, by being that, is the enrichment or the reduction of the monad's mental life.
'But,' our common sense protests, 'it is too great a strain on our credulity to make the real nature of things so utterly different from what sense and science make of them. If the real universe is what you say it is, why do our minds represent it to us as they do?' The philosopher's answer is, 'Because they represent it. According to the truth of things, each monad is simply its own mental life, its own world-view, its own thoughts and desires. To know things as they are would be simultaneously to live over, as though from within and by a miracle of sympathy, the  biographies of an infinite number of distinct monads. This is absolutely impossible. Our senses represent the coexistent families of monads in the gross, and therefore conventionally; what is in fact the mutual representation of monads in ordered systems, is represented as the mechanical interaction of spatially extended and material parts.' This does not mean that science is overthrown. The physical world-view is in terms of the convention of representation, but it is not, for all that, illusory. It can, ideally, be made as true as it is capable of being. There is no reason whatever for confusing the 'well-grounded seemings' of the apparent physical world with the fantastic seemings of dream and hallucination.
So far the argument seems to draw whatever cogency it has from the simplicity and naturalness of the notion of representation. The nature of idea, it is assumed, is to represent plurality in a unified view. If idea did not represent, it would not be idea. And since there is idea (for our minds at least exist and are made up of idea) there is representation. It belongs to idea to represent, and since the whole world has now been interpreted as a system of mutually representing ideations, or ideators, it might seem that all their mutual relations are perfectly natural, a harmony of agreement which could not be other than it is. But if so, why does Leibniz keep saying that the harmony is pre-established, by special and infinitely elaborate divine decrees?
Leibniz himself says that the very nature of representation excludes interaction. By representing environment a mind does not do anything to environment, that is plain. But it is no less plain that environment does nothing to it, either. The act of representing is simply the act of the mind; it represents in view of environment, of course, but not under the causal influence of environment. Representation is a business carried on by the mind on its own account, and in virtue of its innate power to represent.
Very well; but does this consideration really drive us into theology? Is not Leibniz the victim of a familiar fallacy, that of incompletely stated alternatives? 'Either finite beings interact or else they do not directly condition one another. Monads do not interact, therefore they do not directly condition one another. How then explain the actual conformity of their mutual representation, without recourse to divine fore-ordaining?' It seems sufficient to introduce a further alternative in the first line of the argument, and we are rid of the theology. Things may condition the  action of a further thing, without acting upon it. It acts of itself, but it acts in view of what they are. We are tempted to conclude that Leibniz has introduced the Deus ex machina with the fatal facility of his age. 'Where a little further meditation on the characters in the play would furnish a natural denouement, he swings divine intervention on to the scene by wires from the ceiling. It is easy for us to reconstruct for him the end of the piece without recourse to stage-machines.'
Is it? No, I fear it is not. There is really no avoiding the pre-established harmony. And so we shall discover, if we pursue our train of reflexion a little further. It is natural, we were saying, than an idea should represent an environment; indeed, it is the representation of one. Given no environment to represent, it would be empty, a mere capacity for representation. Then every idea or ideator, taken merely in itself, is an empty capacity. But of what is the environment of each made up? According to the Leibnitian theory, of further ideas or ideators: of empty capacities, therefore. Then no idea will either be anything in itself, or find anything in its neighbours to represent. An unhappy predicament, like that of a literary clique in which all the members are adepts at discussing one another's ideas—only that unfortunately none of them are provided with any; or like the shaky economics of the fabled Irish village where they all lived by taking in one another's washing.
It is useless, then, to conceive representations as simply coming into existence in response to environment, and modelling themselves on environment. They must all mutually reflect environment or they would not be representations; but they must also exist as themselves and in their own right or there would be no environment for them mutually to represent. Since the world is infinitely various, each representor must have its own distinct character or nature, as our minds have: that is to say, it must represent in its own individual way; and all these endlessly various representations must be so constituted as to form a mutually reflecting harmony. Considered as a representation, each monadical existence simply reflects the universe after its own manner. But considered as something to be represented by the others, it is a self-existent mental life, or world of ideas. Now when we are considering the fact of representation, that which is to be represented comes first and the representation follows upon it. Thus in considering the Leibnitian universe, we must begin with the monads as self-existent mental lives, or worlds of ideas; their representation of one another comes second. Nothing surely, then, but omnipotent creative wisdom could have pre-established between so many distinct given mental worlds that harmony which constitutes their mutual representation.
Our common-sense pluralistic thinking escapes from the need of the pre-established harmony by distinguishing what we are from what we do. Let the world be made up of a plurality of agents in a 'loose' order, with room to manoeuvre and to adjust themselves to one another. Then, by good luck or good management, through friction and disaster, by trial and error, by accident or invention, they may work out for themselves a harmony of action. There is no need for divine preordaining here. But on Leibniz's view what the monads do is to represent, and what they are is representation; there is no ultimate distinction between what they are and what they do: all that they do belongs to what they are. The whole system of action in each monad, which fits with such infinite complexity the system of action in each other monad, is precisely the existence of that monad, and apart from it the monad is not. The monads do not achieve a harmony, they are a harmony, and therefore they are pre-established in harmony.
Leibniz denied that he invoked God to intervene in nature, or that there was anything arbitrary or artificial about his physical theology. He was simply analysing nature and finding it to be a system of mutual representation; he was analysing mutual representation and finding it to be of its nature intrinsically pre-established, and therefore God-dependent. He was not adding anything to mutual representation, he was just showing what it necessarily contained or implied. At least he was doing nothing worse than recognized scholastic practice. Scholastic Aristotelianism explained all natural causality as response to stimulus, and then had to postulate a stimulus which stimulated without being stimulated, and this was God. Apart from this supreme and first stimulus nothing would in fact be moving. The Aristotelians claimed simply to be analysing the nature of physical motion as they perceived it, and to find the necessity of perpetually applied divine stimulation implicit in it. No violence was thereby done to the system of physical motion nor was anything brought in from without to patch it up; it was simply found to be of its own  nature God-dependent.
It seems as though the reproachful description 'Deus ex machina' should be reserved for more arbitrary expedients than Aristotle's or Leibniz's, say for the occasionalist theory. Occasionalism appeared to introduce God that he might make physical matter do what it had no natural tendency to do, viz. to obey the volitions of finite mind. Ideas, on the other hand, have a natural tendency to represent one another, for to be an idea is to be a representation; God is not introduced by Leibniz to make them correspond, he is introduced to work a system in which they shall correspond. This may not be Deus-ex-machina philosophy, but it is physical theology; that is to say, it treats divine action as one factor among the factors which together constitute the working of the natural system. And this appears to be perhaps unscientific, certainly blasphemous: God's action cannot be a factor among factors; the Creator works through and in all creaturely action equally; we can never say 'This is the creature, and that is God' of distinguishable causalities in the natural world. The creature is, in its creaturely action, self-sufficient: but because a creature, insufficient to itself throughout, and sustained by its Creator both in existence and in action.
The only acceptable argument for theism is that which corresponds to the religious consciousness, and builds upon the insufficiency of finite existence throughout, because it is finite. All arguments to God's existence from a particular gap in our account of the world of finites are to be rejected. They do not indicate God, they indicate the failure of our power to analyse the world-order. When Leibniz discovered that his system of mutual representations needed to be pre-established, he ought to have seen that he had come up a cul-de-sac and backed out; he ought not to have said, 'With the help of God I will leap over the wall.'
If we condemn Leibniz for writing physical theology, we condemn not him but his age. No contemporary practice was any better, and much of it a good deal worse, as Leibniz liked somewhat complacently to point out. And because he comes to theology through physical theology, that does not mean that all his theology was physical theology and as such to be written off. On the contrary, Leibniz is led to wrestle with many problems which beset any philosophical theism of the Christian type. This is particularly so in the Theodicy, as its many citations of theologians suggest. His discussions never lack ingenuity, and the system of creation and providence in which they result has much of that luminous serenity which colours the best works of the Age of Reason.
Every theistic philosopher is bound, with whatever cautions, to conceive God by the analogy of the human mind. When Leibniz declares the harmony of monads to be pre-established by God, he is invoking the image of intelligent human pre-arrangement. Nor is he content simply to leave it at that: he endeavours as well as he may to conceive the sort of act by which God pre-arranges; and this involves the detailed adaptation for theological purposes of Leibnitian doctrine about the human mind.
The human mind, as we have seen, is the mind predominant in a certain system of 'minds', viz. in those which constitute the members of the human body. If we call it predominant, we mean that its system of ideas is more developed than theirs, so that there are more points in which each of them conforms to it than in which it conforms to any one of them. The conception of a divine pre-establishing mind will be analogous. It will be the conception of a mind absolutely dominant, to whose ideas, that is to say, the whole system simply corresponds, without any reciprocating correspondence on his side. In a certain sense this is to make God the 'Mind of the World'; and yet the associations of the phrase are misleading. It suggests that the world is an organism or body in which the divine mind is incarnate, and on which he relies for his representations. But that is nonsense; the world is not a body, nor is it organic to God. Absolute dominance involves absolute transcendence: if everything in the world without remainder simply obeys the divine thoughts, that is only another way of saying that the world is the creature of God; the whole system is pre-established by him who is absolute Being and perfectly independent of the world.
Of createdness, or pre-establishedness, there is no more to be said: we can think of it as nothing but the pure or absolute case of subjection to dominant mind. It is no use asking further how God's thoughts are obeyed in the existence and action of things. What we can and must enquire into further, is the nature of the divine thoughts which are thus obeyed. They must be understood to be volitions or decrees. There are indeed two ways in which things obey the divine thought, and correspondingly two sorts of divine thoughts that they obey. In so far as created things conform to  the mere universal principles of reason, they obey a reasonableness which is an inherent characteristic of the divine mind itself. If God wills the existence of any creature, that creature's existence must observe the limits prescribed by eternal reason: it cannot, for example, both have and lack a certain characteristic in the same sense and at the same time; nor can it contain two parts and two parts which are not also countable as one part and three parts. Finite things, if they exist at all, must thus conform to the reasonableness of the divine nature, but what the divine reasonableness thus prescribes is highly general: we can deduce from it only certain laws which any finite things must obey, we can never deduce from it which finite things there are to be, nor indeed that there are to be any. Finite things are particular and individual: each of them might have been other than it is or, to speak more properly, instead of any one of them there might have existed something else; it was, according to the mere principles of eternal reason, equally possible. But if so, the whole universe, being made up of things each of which might be otherwise, might as a whole be otherwise. Therefore the divine thoughts which it obeys by existing have the nature of choices or decrees.
What material does the finite mind supply for an analogical picture of the infinite mind making choices or decrees? If we use such language of God, we are using language which has its first and natural application to ourselves. We all of us choose, and those of us who are in authority make decrees. What is to choose? It involves a real freedom in the mind. A finite mind, let us remember, is nothing but a self-operating succession of perceptions, ideas, or representations. With regard to some of our ideas we have no freedom, those, for example, which represent to us our body. We think of them as constituting our given substance. They are sheer datum for us, and so are those reflexions of our environment which they mediate to us. They make up a closely packed and confused mass; they persevere in their being with an obstinate innate force, the spiritual counterpart of the force which we have to recognize in things as physically interpreted. Being real spiritual force, it is quasi-voluntary, and indeed do we not love our own existence and, in a sense, will it in all its necessary circumstances? But if we can be said to will to be ourselves and to enact with native force what our body and its environment makes us, we are  merely willing to conform to the conditions of our existence; we are making no choice. When, however, we think freely or perform deliberate acts, there is not only force but choice in our activity. Choice between what? Between alternative possibilities arising out of our situation. And choice in virtue of what? In virtue of the appeal exercised by one alternative as seemingly better.
Can we adapt our scheme of choice to the description of God's creative decrees? We will take the second point in it first: our choice is in virtue of the appeal of the seeming best. Surely the only corrective necessary in applying this to God is the omission of the word 'seeming'. His choice is in virtue of the appeal of the simply best. The other point causes more trouble. We choose between possibilities which arise for us out of our situation in the system of the existing world. But as the world does not exist before God's creative choices, he is in no world-situation, and no alternative possibilities can arise out of it, between which he should have to choose. But if God does not choose between intrinsic possibilities of some kind, his choice becomes something absolutely meaningless to us—it is not a choice at all, it is an arbitrary and unintelligible fiat.
Leibniz's solution is this: what are mere possibilities of thought for us are possibilities of action for God. For a human subject, possibilities of action are limited to what arises out of his actual situation, but possibilities for thought are not so limited. I can conceive a world different in many respects from this world, in which, for example, vegetables should be gifted with thought and speech; but I can do nothing towards bringing it about. My imaginary world is practically impossible but speculatively possible, in the sense that it contradicts no single principle of necessary and immutable reason. I, indeed, can explore only a very little way into the region of sheer speculative possibility; God does not explore it, he simply possesses it all: the whole region of the possible is but a part of the content of his infinite mind. So among all possible creatures he chooses the best and creates it.
But the whole realm of the possible is an actual infinity of ideas. Out of the consideration of an infinity of ideas, how can God arrive at a choice? Why not? His mind is not, of course, discursive; he does not successively turn over the leaves of an infinite book of sample worlds, for then he would never come to the end of it. Embracing infinite possibility in  the single act of his mind, he settles his will with intuitive immediacy upon the best. The inferior, the monstrous, the absurd is not a wilderness through which he painfully threads his way, it is that from which he immediately turns; his wisdom is his elimination of it.
But in so applying the scheme of choice to God's act, have we not invalidated its application to our own? For if God has chosen the whole form and fabric of the world, he has chosen everything in it, including the choices we shall make. And if our choices have already been chosen for us by God, it would seem to follow that they are not real open choices on our part at all, but are pre-determined. And if they are pre-determined, it would seem that they are not really even choices, for a determined choice is not a choice. But if we do not ourselves exercise real choice in any degree, then we have no clue to what any choice would be: and if so, we have no power of conceiving divine choice, either; and so the whole argument cuts its own throat.
There are two possible lines of escape from this predicament. One is to define human choice in such a sense that it allows of pre-determination without ceasing to be choice; and this is Leibniz's method, and it can be studied at length in the Theodicy. He certainly makes the very best he can of it, and it hardly seems that any of those contemporaries whose views he criticizes was in a position to answer him. The alternative method is to make the most of the negative element involved in all theology. After all, we do not positively or adequately understand the nature of infinite creative will. Perhaps it is precisely the transcendent glory of divine freedom to be able to work infallibly through free instruments. But so mystical a paradox is not the sort of thing we can expect to appeal to a late-seventeenth-century philosopher.
One criticism of Leibniz's argument we cannot refrain from making. He allows himself too easy a triumph when he says that the only alternative to a choice determined by a prevailing inclination towards one proposal is a choice of mere caprice. There is a sort of choice Leibniz never so much as considers and which appears at least to fall quite outside his categories, and that is the sort of choice exercised in artistic creativity. In such choice we freely feel after the shaping of a scheme, we do not arbitrate simply between shaped and given possible schemes. And perhaps some such element enters into all our choices, since our life is to some extent  freely designed by ourselves. If so, our minds are even more akin to the divine mind than Leibniz realized. For the sort of choice we are now referring to seems to be an intuitive turning away from an infinite, or at least indefinite, range of less attractive possibility. And such is the nature of the divine creative choice. The consequence of such a line of speculation would be, that the divine mind designs more through us, and less simply for us, than Leibniz allowed: the 'harmony' into which we enter would be no longer simply 'pre-established'. Leibniz, in fact, could have nothing to do with such a suggestion, and he would have found it easy to be ironical about it if his contemporaries had proposed it.
Leibniz wrote two books; a considerable number of articles in learned periodicals; and an enormous number of unpublished notes, papers and letters, preserved in the archives of the Electors of Hanover not because of the philosophical significance of some of them, but because of the political importance of most of them. From among this great mass various excerpts of philosophical interest have been made by successive editors of Leibniz's works. It may be that the most profound understanding of his mind is to be derived from some of these pieces, but if we wish to consider the public history of Leibniz, we may set them aside.
Of the two books, one was published, and the other never was. The New Essays remained in Leibniz's desk, the Theodicy saw the light. And so, to his own and the succeeding generation, Leibniz was known as the author of the Theodicy.
The articles in journals form the immediate background to the two books. In 1696 Leibniz heard that a French translation of Locke's Essay concerning Human Understanding was being prepared at Amsterdam. He wrote some polite comments on Locke's great work, and published them. He also sent them to Locke, hoping that Locke would write a reply, and that Leibniz's reflexions and Locke's reply might be appended to the projected French translation. But Locke set Leibniz's comments aside. Leibniz, not to be defeated, set to work upon the New Essays, in which the whole substance of Locke's book is systematically discussed in dialogue. The New Essays were written in 1703. But meanwhile a painful dispute had broken out between Leibniz  and the disciples of Locke and Newton, in which the English, and perhaps Newton himself, were much to blame, and Leibniz thought it impolitic to publish his book. It was not issued until long after his death, in the middle of the century.
The discussion with Locke was a failure: Locke would not play, and the book in which the whole controversy was to be systematized never appeared. The discussion with Bayle, on the other hand, was a model of what a discussion should be. Bayle played up tirelessly, and was never embarrassingly profound; he provided just the sort of objections most useful for drawing forth illuminating expositions; he was as good as a fictitious character in a philosophical dialogue. And the book in which the controversy was systematized duly appeared with great eclat.
Here is the history of the controversy. In 1695 Leibniz was forty-nine years old. He had just emerged from a period of close employment under his prince's commands, and he thought fit to try his metaphysical principles upon the polite world and see what would come of it. He therefore published an article in the Journal des Savants under the title: 'New System of Nature and of the Communication of Substances, as well as of the Union between Soul and Body'. In the same year Foucher published an article in the Journal controverting Leibniz; and in the next year Leibniz replied with an 'Explanation'. A second explanation in the same year appeared in Basnage's Histoire des Ouvrages des Savants, in answer to reflexions by the editor. M. Pierre Bayle had all these articles before him when he inserted a note on Leibniz's doctrine in his article on 'Rorarius', in the first edition of his Historical and Critical Dictionary. The point of connexion between Rorarius and Leibniz was no more than this, that both held views about the souls of beasts.
Pierre Bayle was the son of a Calvinist pastor, early converted to Catholicism, but recovered to his old faith after a short time. He held academic employments in Switzerland and Holland; he promoted and edited the Nouvelles de la Republique des Lettres, and he produced that extraordinary work the Historical and Critical Dictionary. The notices it contains of authors and thinkers are little more than pegs upon which Bayle could hang his philosophical reflexions. He could write an intelligent discussion on any opinion; what he could not do was to reconcile the points of view from which he felt impelled to write upon this author and that. His was not a systematic mind. So far as he had a philosophical opinion, he was a Cartesian; in theology he was an orthodox Calvinist. He could not reconcile his theology with his Cartesianism and he did not try to. He made a merit of the oppositions of faith to reason and reason to itself, so that he could throw himself upon a meritorious and voluntary faith.
There is nothing original in this position. It was characteristic of decadent scholasticism, it squared with Luther's exaggerations about the impotence of reason in fallen man, and Pascal had given his own highly personal twist to it. Bayle has been hailed as a forerunner of Voltairean scepticism. It would be truer to say that a Voltairean sceptic could read Bayle's discussions in his own sense and for his own purposes if he wished. But Bayle was not a sceptic. It is hard to say what he was; his whole position as between faith and reason is hopelessly confused. He was a scholar, a wit, and a philosophical sparring-partner of so perfectly convenient a kind that if we had not evidence of his historical reality, we might have suspected Leibniz of inventing him.
In the first edition of his Dictionary, under the article 'Rorarius', Bayle gave a very fair account of Leibniz's doctrine concerning the souls of animals, as it could be collected from his article in the Journal des Savants, 27 June 1695. He then proceeded to comment upon it in the following terms:
'There are some things in Mr. Leibniz's hypothesis that are liable to some difficulties, though they show the great extent of his genius. He will have it, for example, that the soul of a dog acts independently of outward bodies; that it stands upon its own bottom, by a perfect spontaneity with respect to itself, and yet with a perfect conformity to outward things.... That its internal perceptions arise from its original constitution, that is to say, the representative constitution (capable of expressing beings outside itself in relation to its organs) which was bestowed upon it from the time of its creation, and makes its individual character (Journal des Savants, 4 July 1695). From whence it results that it would feel hunger and thirst at such and such an hour, though there were not any one body in the universe, and though nothing should exist but God and that soul. He has explained (Histoire des Ouvrages des Savants, Feb. 1696) his thought by the example of two pendulums that should perfectly agree: that is, he supposes that according to the particular laws which put the soul upon action, it must feel hunger at such an hour;  and that according to the particular laws which direct the motion of matter, the body which is united to that soul must be modified at that same hour as it is modified when the soul is hungry. I will forbear preferring this system to that of occasional causes till the learned author has perfected it. I cannot apprehend the connexion of internal and spontaneous actions which would have this effect, that the soul of a dog would feel pain immediately after having felt joy, though it were alone in the universe. I understand why a dog passes immediately from pleasure to pain when, being very hungry and eating a piece of bread, he is suddenly struck with a cudgel. But I cannot apprehend that his soul should be so framed that at the very moment of his being beaten he should feel pain though he were not beaten, and though he should continue to eat bread without any trouble or hindrance. Nor do I see how the spontaneity of that soul should be consistent with the sense of pain, and in general with any unpleasing perceptions.
'Besides, the reason why this learned man does not like the Cartesian system seems to me to be a false supposition; for it cannot be said that the system of occasional causes brings in God acting by a miracle (ibid.), Deum ex machina, in the mutual dependency of the body and soul: for since God does only intervene according to general laws, he cannot be said to act in an extraordinary manner. Does the internal and active virtue communicated to the forms of bodies according to M. Leibniz know the train of actions which it is to produce? By no means; for we know by experience that we are ignorant whether we shall have such and such perceptions in an hour's time. It were therefore necessary that the forms should be directed by some internal principle in the production of their acts. But this would be Deus ex machina, as much as in the system of occasional causes. In fine, as he supposes with great reason that all souls are simple and indivisible, it cannot be apprehended how they can be compared with a pendulum, that is, how by their original constitution they can diversify their operations by using the spontaneous activity bestowed upon them by their Creator. It may clearly be conceived that a simple being will always act in a uniform manner, if no external cause hinders it. If it were composed of several pieces, as a machine, it would act different ways, because the peculiar activity of each piece might change every moment the progress of others; but how will you find in a simple substance the  cause of a change of operation?'
Leibniz published a reply to Bayle in the Histoire des Ouvrages des Savants for July 1698. As in all his references to Bayle, he is studiously polite and repays compliment for compliment. The following are perhaps the principal points of his answer.
1. On the example of the dog:
(a) How should it of itself change its sentiment, since everything left to itself continues in the state in which it is? Because the state may be a state of change, as in a moving body which, unless hindered, continues to move. And such is the nature of simple substances—they continue to evolve steadily.
(b) Would it really feel as though beaten if it were not beaten, since Leibniz says that the action of every substance takes place as though nothing existed but God and itself? Leibniz replies that his remark refers to the causality behind an action, not to the reasons for it. The spontaneous action of the dog, which leads to the feeling of pain, is only decreed to be what it is, for the reason that the dog is part of a world of mutually reflecting substances, a world which also includes the cudgel.
(c) Why should the dog ever be displeased spontaneously? Leibniz distinguishes the spontaneous from the voluntary: many things occur in the mind, of itself, but not chosen by it.
2. On Cartesianism and miracle:
Cartesianism in the form of occasionalism does involve miracle, for though God is said by it to act according to laws in conforming body and mind to one another, he thereby causes them to act beyond their natural capacities.
3. On the problem, how can the simple act otherwise than uniformly?
Leibniz distinguishes: some uniform action is monotonous, but some is not. A point moves uniformly in describing a parabola, for it constantly fulfils the formula of the curve. But it does not move monotonously, for the curve constantly varies. Such is the uniformity of the action of simple substances.
Bayle read this reply, and was pleased but not satisfied with it. In the second edition of the dictionary, under the same article 'Rorarius', he added the following note:
'I declare first of all that I am very glad I have proposed some small difficulties against the system of that great philosopher, since they  have occasioned some answers whereby that subject has been made clearer to me, and which have given me a more distinct notion of what is most to be admired in it. I look now upon that new system as an important conquest, which enlarges the bounds of philosophy. We had only two hypotheses, that of the Schools and that of the Cartesians: the one was a way of influence of the body upon the soul and of the soul upon the body; the other was a way of assistance or occasional causality. But here is a new acquisition, a new hypothesis, which may be called, as Fr. Lami styles it, a way of pre-established harmony. We are beholden for it to M. Leibniz, and it is impossible to conceive anything that gives us a nobler idea of the power and wisdom of the Author of all things. This, together with the advantage of setting aside all notions of a miraculous conduct, would engage me to prefer this new system to that of the Cartesians, if I could conceive any possibility in the way of pre-established harmony.
'I desire the reader to take notice that though I confess that this way removes all notions of a miraculous conduct, yet I do not retract what I have said formerly, that the system of occasional causes does not bring in God acting miraculously. (See M. Leibniz's article in Histoire des Ouvrages des Savants, July 1698.) I am as much persuaded as ever I was that an action cannot be said to be miraculous, unless God produces it as an exception to the general laws; and that everything of which he is immediately the author according to those laws is distinct from a miracle properly so called. But being willing to cut off from this dispute as many things as I possibly can, I consent it should be said that the surest way of removing all notions that include a miracle is to suppose that all created substances are actively the immediate causes of the effects of nature. I will therefore lay aside what I might reply to that part of M. Leibniz's answer.
'I will also omit all objections which are not more contrary to his opinion than to that of some other philosophers. I will not therefore propose the difficulties that may be raised against the supposition that a creature can receive from God the power of moving itself. They are strong and almost unanswerable, but M. Leibniz's system does not lie more open to them than that of the Aristotelians; nay, I do not know whether the Cartesians would presume to say that God cannot communicate to our souls a power of acting. If they say so, how can they own that Adam sinned? And if they dare not say so they weaken the arguments whereby they endeavour to prove that matter is not capable of any activity. Nor do I believe that it is more difficult for M. Leibniz than for the Cartesians or other philosophers, to free himself from the objection of a fatal mechanism which destroys human liberty. Wherefore, waiving this, I shall only speak of what is peculiar to the system of the pre-established harmony.
'I. My first observation shall be, that it raises the power and wisdom of the divine art above everything that can be conceived. Fancy to yourself a ship which, without having any sense or knowledge, and without being directed by any created or uncreated being, has the power of moving itself so seasonably as to have always the wind favourable, to avoid currents and rocks, to cast anchor where it ought to be done, and to retire into a harbour precisely when it is necessary. Suppose such a ship sails in that manner for several years successively, being always turned and situated as it ought to be, according to the several changes of the air and the different situations of seas and lands; you will acknowledge that God, notwithstanding his infinite power, cannot communicate such a faculty to a ship; or rather you will say that the nature of a ship is not capable of receiving it from God. And yet what M. Leibniz supposes about the machine of a human body is more admirable and more surprising than all this. Let us apply his system concerning the union of the soul with the body to the person of Julius Caesar.