u2Leibniz 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[11] 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[12] 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.

[13] 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 [14] 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.