Historians often speak as if philosophy took an entirely fresh start at different epochs of its existence. One such break is variously associated with Descartes, or Bacon, or some one of their Italian predecessors. In like manner, the introduction of Christianity, coupled with the closing of the Athenian schools by Justinian, is considered, as once was the suppression of the West-Roman Caesarate by Odoacer, to mark the beginning of a new régime. But there can be no more a real break in the continuity of intellectual than in the continuity of political history, beyond what sleep or inactivity may simulate in the life of the organic aggregate no less than in the life of the organic individual. In each instance, the thread is taken up where it was dropped. If the rest of the world has been advancing meanwhile, new tendencies will come into play, but only by first attaching themselves to older lines of movement. Sometimes, again, what seems to be a revolution is, in truth, the revival or liberation of an earlier movement, through the decay or destruction of beliefs which have hitherto checked its growth. Thus the systems of Plato and Aristotle, after carrying all before them for a brief period, were found unsuitable, from their vast comprehension and high spirituality, to the undeveloped consciousness of their age, and were replaced by popularised versions of the sceptical or naturalistic philosophies which they had endeavoured to suppress. And when these were at length left behind by the forward movement of the human mind, speculative reformers spontaneously reverted to the two great Socratic thinkers for a better solution of the problems in debate. After many abortive efforts, a teacher appeared possessing sufficient genius to fuse their principles into a seemingly coherent and comprehensive whole. By combining the Platonic and Aristotelian spiritualism with a dynamic element borrowed from Stoicism, Plotinus did for an age of intellectual decadence what his models had done in vain for an age of intellectual growth. The relation in which he stood to Stoicism, Epicureanism, and Scepticism, reproduced the relation in which they stood to the various physical and sophistic schools of their time; but the silent experience of six centuries won for him a much more enduring success.

Neo-Platonism was the form under which Greek philosophy passed into Christian teaching; and the transition was effected with less difficulty because Christianity had already absorbed some of its most essential elements from the original system of Plato himself. Meanwhile the revival of spiritualism had given an immense impulse to the study of the classic writings whence it was drawn; and the more they were studied the more prominently did their antagonism on certain important questions come into view. Hence, no sooner did the two systems between which Plotinus had established a provisional compromise come out victorious from their struggle with materialism, than they began to separate and draw off into opposing camps. The principal subject of dispute was the form under which ideas exist. The conflicting theories of Realism and Nominalism are already set forth with perfect clearness by Porphyry in his introduction to the Organon; and his statement of the case, as Victor Cousin has pointed out, gave the signal for a controversy forming the central interest of Scholasticism during the entire period of its duration.

Now, it is a remarkable fact, and one as yet not sufficiently attended to, that a metaphysical issue first raised between the Platonists and Aristotle, and regarded, at least by the latter, as of supreme importance for philosophy, should have been totally neglected at a time when abundant documents on both sides were open to consultation, and taken up with passionate eagerness at a time when not more than one or two dialogues of Plato and two or three tracts of Aristotle continued to be read in the western world. Various explanations of this singular anomaly may be offered. It may be said, for instance, that after every moral and religious question on which the schools of Athens were divided had been closed by the authoritative ruling of Catholicism, nothing remained to quarrel over but points too remote or too obscure for the Church to interfere in their decision; and that these were accordingly seized upon as the only field where human intelligence could exercise itself with any approach to freedom. The truth, however, seems to be that to take any interest in the controversy between Realism and Nominalism, it was first necessary that European thought as a whole should rise to a level with the common standpoint of their first supporters. This revolution was effected by the general adoption of a monotheistic faith.

Moreover, the Platonic ideas were something more than figments of an imaginative dialectic. They were now beginning to appear in their true light, and as what Plato had always understood them to be—no mere abstractions from experience, but spiritual forces by which sensuous reality was to be reconstituted and reformed. The Church herself seemed something more than a collection of individuals holding common convictions and obeying a common discipline; she was, like Plato’s own Republic, the visible embodiment of an archetype laid up in Heaven.[533] And the Church’s teaching seemed also to assume the independent reality of abstract ideas. Does not the Trinity involve belief in a God distinct from any of the Divine Persons taken alone? Do not the Fall, the Incarnation, and the Atonement become more intelligible if we imagine an ideal humanity sinning with the first Adam and purified by becoming united with the second Adam? Such, at least, seems to have been the dimly conceived metaphysics of St. Paul, whatever may now be the official doctrine of Rome. It was, therefore, in order that, during the first half of the Middle Ages, from Charlemagne to the Crusades, Realism should have been the prevailing doctrine; the more so because Plato’s Timaeus, which was studied in the schools through that entire period, furnishes its readers with a complete theory of the universe; while only the formal side of Aristotle’s philosophy is represented by such of his logical treatises as were then known to western Christendom.

Yet Realism concealed a danger to orthodoxy which was not long in making itself felt. Just as the substantiality of individuals disappeared in that of their containing species, so also did every subordinate species tend to vanish in the summum genus of absolute Being. Now such a conclusion was nothing less than full-blown pantheism; and pantheism was, in fact, the system of the first great Schoolman, John Scotus Erigena; while other Realists were only prevented from reaching the same goal by the restraint either of Christian faith or of ecclesiastical authority. But if they failed to draw the logical consequences of their premises, it was drawn for them by others; and Abélard did not fail to twit his opponents with the formidable heresy implied in their realistic principles.[534] As yet, however, the weight of authority inclined towards Plato’s side; and the persecution suffered by Abélard himself, as compared with the very mild treatment accorded to his contemporary, Gilbert de la Porrée, when each was arraigned on a charge of heresy, shows that while the Nominalism of the one was an aggravation, the Realism of the other was an extenuation of his offence.[535]

So matters stood when the introduction of Aristotle’s entire system into western Europe brought about a revolution comparable to that effected two centuries later by the complete recovery of ancient literature. It was through Latin translations from the Arabic, accompanied by Arabic commentaries, that the Peripatetic philosophy was first revealed in its entirety; and even Albertus Magnus, living in the thirteenth century, seems to have derived his knowledge of the subject from these exclusively. But a few years after the capture of Constantinople by the Crusaders in 1204, the Greek manuscripts of Aristotle were brought to Paris; and, towards the middle of the century, a new Latin version was made from these under the supervision of St. Thomas Aquinas.[536] The triumph of Aristotle was now, at least for a time, secured. For, while in the first period of the Middle Ages we find only a single great name, that of Abélard, among the Nominalists, against a strong array of Realists, in the second period the proportions are reversed, and Realism has only a single worthy champion, Duns Scotus, to pit against Albertus, Aquinas, and William of Ockham, each of them representing one of the principal European nations.[537] The human intellect, hitherto confined within the narrow bounds of logic, now ranged over physics, metaphysics, psychology, and ethics; and although all these subjects were studied only at second-hand, and with very limited opportunities for criticism, still the benefit received must have been immense. The priceless service of the later Schoolmen is to have appropriated and successfully upheld, against Platonism on the one hand and theological mysticism on the other, a philosophy which, however superficial, took in the whole range of natural phenomena, derived all knowledge from external observation, and set an example of admirable precision in the systematic exposition of its results. If no positive addition was made to that vast storehouse of facts and ideas, the blame does not lie with Aristotle’s method, but with the forcible suppression of free mental activity by the Church, or its diversion to more profitable fields by the study of Roman jurisprudence. Even as it was, Aristotle contributed largely to the downfall of ecclesiastical authority in two ways: directly by accustoming men to use their reason, and indirectly by throwing back mysticism on its proper office—the restoration of a purely personal religion.

But before the dissolving action of Nominalism had become fully manifest, its ascendency was once more challenged; and this time, also, the philosophical impulse came from Constantinople. Greek scholars, seeking help in the West, brought with them to Florence the complete works of Plato; and these were shortly made accessible to a wider public through the Latin translation of Ficino. Their influence seems at first to have told in favour of mysticism, for this was the contemporary tendency to which they could be most readily affiliated; and, besides, in swinging back from Aristotle’s philosophy to the rival form of spiritualism, men’s minds naturally reverted, in the first instance, to what had once linked them together—the system of Plotinus. Thus Platonism was studied through an Alexandrian medium, and as the Alexandrians had looked at it, that is to say, chiefly under its theological and metaphysical aspects. As such, it became the accepted philosophy of the Renaissance; and much of what we most admire in the literature—at least the English literature—of that period, is directly traceable to Platonic influence. That the Utopia of Sir Thomas More was inspired by the Republic and the Critias is, of course, obvious; and the great part played by the ideal theory in Spenser’s Faery Queen, though less evident, is still sufficiently clear. As Mr. Green observes in his History of the English People (II., p. 413), ‘Spenser borrows, in fact, the delicate and refined forms of the Platonic philosophy to express his own moral enthusiasm.... Justice, Temperance, Truth are no mere names to him, but real existences to which his whole nature clings with a rapturous affection.’ Now it deserves observation, as illustrating a great revolution in European thought, that the relation of Plato to the epic of the English Renaissance is precisely paralleled by the relation of Aristotle to the epic of mediaeval Italy. Dante borrows more than his cosmography from the Stagirite. The successive circles of Hell, the spirals of Purgatory, and the spheres of Paradise, are a framework in which the characters of the poem are exhibited, not as individual actors whom we trace through a life’s history, but as types of a class and representatives of a single mental quality, whether vicious or virtuous. In other words, the historical arrangement of all previous poems is abandoned in favour of a logical arrangement. For the order of contiguity in time is substituted the order of resemblance and difference in idea. How thoroughly Aristotelian, indeed, were the lines within which mediaeval imagination moved is proved by the possibility of tracing them in a work utterly different from Dante’s—the Decameron of Boccaccio. The tales constituting this collection are so arranged that each day illustrates some one special class of adventures; only, to make good Aristotle’s principle that earthly affairs are not subject to invariable rules, a single departure from the prescribed subject is allowed in each decade; while during one entire day the story-tellers are left free to choose a subject at their own discretion.

Now what distinguishes Spenser from Dante is that, while he also disposes his inventions according to an extremely artificial and abstract schematism, with him, as with Plato, abstractions acquire a separate individual existence, being, in fact, embodied as so many persons; while Dante, following Aristotle, never separates his from the concrete data of experience. And it may be noted that, in this respect at least, English literature has not deserted the philosophy which presided over its second birth. It has ever since been more prone to realise abstractions than any other literature, whether under the form of allegories, parables, or mere casual illustrations drawn from material objects. Even at this day, English writers crowd their pages with dazzling metaphors, which to Continental readers must have sometimes a rather barbaric effect.

Another and profounder characteristic of Plato, as distinguished from Aristotle, is his thorough-going opposition of reality to appearance; his distrust of sensuous perception, imagination, and opinion; his continual appeal to a hidden world of absolute truth and justice. We find this profounder principle also grasped and applied to poetical purposes in our Elizabethan literature, not only by Spenser, but by a still greater master—Shakespeare. It is by no means unlikely that Shakespeare may have looked into a translation of the Dialogues; at any rate, the intellectual atmosphere he breathed was so saturated with their spirit that he could easily absorb enough of it to inspire him with the theory of existence which alone gives consistency to his dramatic work from first to last. For the essence of his comedies is that they represent the ordinary world of sensible experience as a scene of bewilderment and delusion, where there is nothing fixed, nothing satisfying, nothing true; as something which, because of its very unreality, is best represented by the drama, but a drama that is not without mysterious intimations of a reality behind the veil. In them we have the

Fallings from us, vanishings,