THE influence of Neo-Platonism on the official Christian philosophy of the succeeding period was mainly in the department of psychology. Biblical psychology by itself did not of course fix any determinate scientific view. Its literal interpretation might seem, if anything, favourable to a kind of materialism combined with supernaturalism, like that of Tertullian. Even the Pauline conception of "spirit," regarded at once as an infusion of Deity and as the highest part of the human soul, lent itself quite easily to a doctrine like that of the Stoics, which identified the divine principle in the world with the corporeal element most remote by its lightness and mobility from gross matter. For a system, however, that was to claim on behalf of its supernatural dogmas a certain justification by human reason as a preliminary condition to their full reception by faith, the idea of purely immaterial soul and mind was evidently better adapted. This conception, taken over for the practical purposes of the Church in the scientific form given to it by the Neo-Platonists, has accordingly maintained its ground ever since. The occasional attempts in modern times by sincerely orthodox Christians to fall back upon an exclusive belief in the resurrection of the body, interpreted in a materialistic sense, as against the heathen doctrine of the natural immortality of the soul, have never gained any appreciable following. At the end of the ancient world Platonic idealism, so far as it was compatible with the dualism necessitated by certain portions of the dogmatic system, was decisively adopted. In the East, Greek ecclesiastical writers such as Nemesius, who had derived their culture from Neo­Platonism, transmitted its refutations of materialism to the next age. In the West, St Augustine, who, as is known, was profoundly influenced by Platonism, and who had read Plotinus in a Latin translation, performed the same philosophical service. The great positive result was to familiarise the European mind with the elements of certain metaphysical conceptions elaborated by the latest school of independent philosophy. When the time came for renewed independence, long practice with abstractions had made it easier than it had ever hitherto been—difficult as it still was—to set out in the pursuit of philosophic truth from a primarily subjective point of view.

It was long, however, before Western Europe could even begin to fashion for itself new instruments by provisionally working within the prescribed circle of revealed dogma and subordinated philosophy. The very beginning of Scholasticism is divided by a gulf of more than three centuries from the end of Nco-Platonism; and not for about two centuries more did this lead to any continuous intellectual movement. In the meantime, the elements of culture that remained had been transmitted by Neo-Platonists or writers influenced by them. An especially important position in this respect is held by Boethius, who was born at Rome about 480, was Consul in 510, and was executed by order of Theodoric in 524. In philosophy Boethius represents an eclectic Neo-Platonism turned to ethical account. His translation of Porphyry's logical work has already been mentioned. He also devoted works of his own to the exposition of Aristotle's logic. It was when he had fallen into disgrace with Theodoric that he wrote the De Consolatione Philosophiae; and the remarkable fact has often been noticed that, although certainly a nominal Christian, he turned in adversity wholly to heathen philosophy, not making the slightest allusion anywhere to the Christian revelation. The vogue of the De Consolatione in the Middle Ages is equally noteworthy. Rulers like Alfred, eagerly desirous of spreading all the light that was accessible, seem to have been drawn by a secret instinct to the work of a man of kindred race, who, though at the extreme bound, had still been in living contact with the indigenous culture of the old European world. Another work much read in the same period was the commentary of Macrobius (fl. 400) on the Somnium Scipionis extracted from Cicero's De Republica. Macrobius seems not to have been even a nominal Christian. He quotes Neo-Platonist writers, and, by the impress he has received from their type of thinking, furnishes evidence of the knowledge there was of them in the West.

In the East some influence on theological metaphysics was exercised by Synesius, the friend of Hypatia. Having become a Christian, Synesius unwillingly allowed himself to be made Bishop of Ptolemais (about 410); seeking to reserve the philosophical liberty to treat portions of popular Christianity as mythical, but not quite convinced that this was compatible with the episcopal office. A deeper influence of the same kind, extending to the West, came from the works of the writer known under the name of that "Dionysius the Areopagite" who is mentioned among the converts of St Paul at Athens (Acts 17. 34). As no incontestable reference to those works is found till the sixth century, and as they are characterised by ideas distinctive of the school of Proclus, it is now held that they proceeded from some Christian Platonist trained in the Athenian school. It is possible indeed that the real Dionysius had been a hearer of Proclus himself. We learn from Marinus that not all who attended his lectures were his philosophical disciples. The influence of the series of works, in so far as they were accepted officially, was to fix the "angelology" of the Church in a learned form. They also gave a powerful impulse to Christian mysticism, and, through Scotus Erigena, set going the pantheistic speculations which, as soon as thought once more awoke, began to trouble the faith.

When, about the middle of the ninth century, there emerges the isolated figure of John Scotus Erigena, we may say, far as we still are from anything that can be called sunrise, that

 

now at last the sacred influence

Of light appears, and from the walls of Heaven

Shoots far into the bosom of dim Night

A glimmering dawn.

He has been regarded both as a belated Neo-Platonist and as the first of the Scholastics. In reality he cannot be classed as a Neo-Platonist, for his whole effort was directed towards rationalising that system of dogmatic belief which the Neo­Platonists had opposed from the profoundest intellectual and ethical antipathy. On the other hand, he was deeply influenced by the forms of Neo-Platonic thought transmitted through Dionysius, whose works he translated into Latin; and his own speculations soon excited the suspicion of ecclesiastical authority. His greatest work, the De Divisione Naturae, was in 1225 condemned by Pope Honorius III to be burned. Scotus had, however, begun the characteristic movement of Christian Scholasticism. And Dionysius, who could not well be anathematised consistently with the accredited view about the authorship of his writings—who indeed was canonized, and came to be identified with St Denys of France—had been made current in Latin just at the moment when the knowledge of Greek had all but vanished from the West.

The first period of Scholasticism presents a great gap between Scotus and the next considerable thinkers, who do not appear before the latter part of the eleventh century. Towards the end of the twelfth century, the second period begins through the influx of new Aristotelian writings and of the commentaries upon them by the Arabians. The Arabians themselves, on settling down after their conquest of Western Asia, had found Aristotle already translated into Syriac. Translations were made from Syriac into Arabic. These translations and the Arabian commentaries on them were now translated into Latin, sometimes through Hebrew; the Jews being at this time again the great intermediaries between Asia and Europe. Not long after, translations were made directly from the Greek, texts preserved at Constantinople. Thus Western Europe acquired the complete body of Aristotle's logical writings, of which it had hitherto only possessed a part; and, for the first time since its faint re­awakening to intellectual life, it was put in possession of the works dealing with the content as well as the form of philosophy. After prohibiting more than once the reading of the newly recovered writings, and in particular of the Physics and Metaphysics, the ecclesiastical chiefs at length authorised them; having come to see in the theism of Aristotle, which they were now able to discriminate from the pantheism of pseudo-Aristotelian writings, a preparation for the faith. It is from this period that the predominating scientific authority of Aristotle in the Christian schools must be dated. Taken over as a tradition from the Arabians, it had been by them received from the latest commentators of the Athenian school of Neo­Platonism.

The Arabian philosophy, highly interesting in itself, is still more interesting to us for its effect on the intellectual life of Europe. Aristotelian in basis, it was Neo-Platonic in super­structure. Its distinctive doctrine of an impersonal immortality of the general human intellect is, however, as contrasted both with Aristotelianism and with Neo-Platonism, essentially original. This originality it does not owe to Mohammedanism. Its affinity is rather with Persian and Indian mysticism. Not that Mohammedanism wanted a speculative life of its own; but that which is known to history as "Arabian philosophy" did not belong to that life. The proper intellectual life of Islam was in "theology." From the sharp antagonism which sprang up between the Arabian philosophers and "theologians " seems to date the antithesis which became current especially in the Europe of the Renaissance. For the Greek philosophers, "theology " had meant first a poetic exposition of myths, but with the implication that they contained, either directly or when allegorised, some theory of the origin of things. Sometimes—as occasionally in Aristotle and oftener in the Neo-Platonists—it meant the highest, or metaphysical, part of philosophy. It was the doctrine of God as first principle of things, and was accordingly the expression of pure speculative reason. With Islam, as with Christianity, it might mean this; but it meant also a traditional creed imposed by the authority of Church and State. The creed contained many articles which philosophy might or might not arrive at by the free exercise of reason. To the Mohammedan "theologian," however, these were not points which it was permissible to question, except hypothetically, but principles to argue from. Hence the "philosophers," having made acquaintance with the intellectual liberty of Greece, which they were seeking to naturalise in Arabian science, were led to adopt the custom of describing distinctively as a "theologian" one who speculated under external authority and with a practical purpose. Of course the philosophers claimed to deal equally—or, rather, at a higher level—with divine objects of speculation; but, according to their own view, they were not bound by the definitions of the theologian. At the same time, they were to defer to theology in popular modes of speech, allowing a "theological" truth, or truth reduced to what the multitude could profit by, in distinction from "philosophical" or pure truth. The Jews and the Christians too, they allowed, were in possession of theological truth; each religion being good and sufficient in practice for the peoples with whom it was traditional. The reason of this procedure—which has no precise analogue either in ancient or in modern times—was that the Arabian Hellenising movement was pantheistic, while the three religions known to the philosophers all held to the personality of God. Hence the Arabian philosophy could not, like later Deism, find what it regarded as philosophic truth by denuding all three religions of their discrepant elements. Since they were expressed in rigorously defined creeds, it could not allegorize them as the ancient philosophers had allegorized polytheism. Nor was the method open to it of ostensibly founding a new sect. The dominant religions were theocratic, claiming the right, which was also the duty, of persecution. The consequence was, formulation of the strange doctrine known as that of the "double truth."

Under the dominion of Islam, the "philosophers," in spite of their distinction between the two kinds of truth, were treated by the "theologians" as a hostile sect and reduced to silence. Their distinction, however, penetrated to Christian Europe, where, though condemned by Church Councils, it long held its ground as a defence against accusations of heresy. The orthodox distinction between two spheres of truth, to be investigated by different methods but ultimately not in contradiction, may easily be put in its place. Hence a certain elusiveness which no doubt helped to give it vogue in a society not inwardly quite submissive to the authority of the Church even at the time when the theocracy had apparently crushed all secular and intellectual opposition. The profundity of the revolt is evident alike in the philosophical and in the religious movements that marked the close of the twelfth and the opening of the thirteenth century. The ideas that animated both movements were of singular audacity. In philosophy, the intellectual abstractions of Neo-Platonism, and in particular the abstraction of "matter," were made the ground for a revived naturalistic pantheism. Ideas of "absorption," or impersonal immortality, genuinely Eastern in spirit, may have appealed as speculations to the contemplative ascetics of Orientalized Europe. These were not the only ideas that came to the surface. In common with its dogmas, the Catholic hierarchy was threatened; and, to suppress the uprising, the City of God on earth was completed by the Dominican Inquisition. Yet philosophy, so far as it could be made subservient to orthodoxy, was to be a most important element in the training of the Dominicans themselves. From their Order proceeded Thomas Aquinas, the most systematic thinker of the Middle Ages, at whose hands scholastic Aristotelianism received its consummate perfection. Against older heresies, against "Averroism," against the pantheism of heterodox schoolmen, the Angelic Doctor furnished arguments acceptable to orthodoxy, marshalled in syllogistic array. For a short time, his system could intellectually satisfy minds of the highest power, skilled in all the learning of their age, if only they were in feeling at one with the dominant faith.

Over and above its indirect influence through the psychology of the Fathers, Neo-Platonic thought found direct admission into the orthodox no less than into the heterodox speculation of the Scholastic period. Aquinas quotes largely from Dionysius; and Dante was, as is well known, a student both of Aquinas and of Dionysius himself, whose classification of the "Heavenly Hierarchy" he regarded as a direct revelation communicated by St Paul to his Athenian proselyte. Thus, if we find Neo-Platonic ideas in Dante, there is no difficulty about their source. The line of derivation goes straight back to the teaching of Proclus. We are not reduced to the supposition of an indirect influence from Plotinus through St Augustine. Incidental Neo-Platonic expressions in Dante have not escaped notices. More interesting, however, than any detailed coincidence is the fundamental identity of the poet's conception of the beatific vision with the vision of the intelligible world as figured by Plotinus. Almost equally prominent is the use he makes of the speculative conception of emanation. That the higher cause remains in itself while producing that which is next to it in order of being, is affirmed by Dante in terms that might have come directly from Plotinus or Proclus. And it is essentially by the idea of emanation that he explains and justifies the varying degrees of perfection in created things.

The Neo-Platonism of the Divina Commedia, as might be expected, is found almost exclusively in the Paradiso; though one well-known passage in the Purgatorio, describing the mode in which the disembodied soul shapes for itself a new material envelope, bears obvious marks of the same influence. Here, however, there is an important difference. Dante renders everything in terms of extension, and never, like the Neo­Platonists, arrives at the direct assertion, without symbol, of pure immaterialism. This may be seen in the passage just referred to, as compared with a passage from Porphyry's exposition of Plotinus closely resembling it in thought. While Dante represents the soul as having an actual path from one point of space to another, Porphyry distinctly says that the soul's essence has no locality, but only takes upon itself relations depending on conformity between its dispositions and those of a particular body; the body, whether of grosser or of finer matter, undergoing local movement in accordance with its own nature and not with the nature of soul. Again, the point of exact coincidence between Dante and Plotinus in what they say of the communications between souls that are in the world of being, is that, for both alike, every soul "there" knows the thought of every other without need of speech. Plotinus, however, says explicitly that the individualized intelligences within universal mind are together yet discriminated without any reference to space. What Dante says is that while the souls are not really in the planetary spheres, but only appear in them momentarily, they are really above in the empyrean. Even in his representation of the Deity, the Christian poet still retains his spatial symbolism. God is seen as the minutest and intensest point of light, round which the angels—who are the movers of the spheres—revolve in their ninefold order. At the same time, the divine mind is said to be the place of the primum mobile, thus enclosing the whole universe. Viewed in relation to the universe as distinguished from its cause, the angelic movers are in inverted order, the outermost and not the innermost being now the highest. Thus, by symbol, it is finally suggested that immaterial essence is beyond the distinction of the great and the small in magnitude; but even at the end the symbolism has not disappeared.

Like the completed theocratic organisation of society, the Scholastic system which furnished its intellectual justification was hardly finished before it began to break up from within. St Thomas Aquinas was followed by John Duns Scotus, who, while equally orthodox in belief, limited more the demonstrative power of reason in relation to ecclesiastical dogma. Soon after came William of Ockham, whose orthodoxy is to some extent ambiguous. The criticisms of the Subtle and of the Invincible Doctor had for their effect to show the illusoriness of the systematic harmony which their great predecessor seemed to have given once for all to the structure composed of dominant Catholic theology and subordinated Aristotelian philosophy. Duns Scotus was indirectly influenced by Neo­Platonism, which came to him from the Jewish thinker Ibu Gebirol, known to the schoolmen as Avicebron. This was the source of his theory of a "first matter" which is a component of intellectual as of corporeal substances. His view that the "principle of individuation" is not matter but form, coincides with that of Plotinus. Ockham was a thinker of a different cast, representing, as against the Platonic Realism of Duns Scotus, the most developed form of mediaeval Nominalism. In their different ways, both developments contributed to upset the balance of the Scholastic eirenicon (peace) between science and faith. The rapidity with which the disintegration was now going on may be judged from the fact that Ockham died about 1349, that is, before the end of the half-century which had seen the composition of the Divina Commedia.

The end of Scholasticism as a system appealing to the living world is usually placed about the middle of the fifteenth century. From that time, it became first an obstruction in the way of newer thought, and then a sectarian survival. The six centuries of its effective life are those during which Greek thought was wholly unknown in its sources to the West. John Scotus Erigena was one of the very last who had some knowledge of Greek before the study of it revived in the Italy of Petrarch and Boccaccio. For the new positive beginning of European culture, the classical revival, together with the impulse towards physical research,—represented among the schoolmen by Roger Bacon,—was the essential thing.

In the familiar story of the rise of Humanism, the point that interests us here is that the first ancient system to be appropriated in its content, and not simply studied as a branch of erudition, was Platonism. And it was with the eyes of the Neo-Platonists that the Florentine Academy read Plato himself. Marsilio Ficino, having translated Plato, turned next to Plotinus. His Latin translation of the Enneads appeared in 1492. Platonism was now set by its new adherents against Aristotelianism, whether in the Scholastic form or as restored by some who had begun to study it with the aid of the Greek instead of the Arabian commentaries. The name of Aristotle became for a time to nearly all the innovators the synonym of intellectual oppression.

The Platonists of the early Renaissance were sincere Christians in their on manner. This was not the manner of the Middle Age. The definitely articulated system of ecclesiastical dogma had no real part in their intellectual life. They were Christians in a general way; in the details of their thinking they were Neo-Platonists. In relation to astrology and magic, indeed, they were Neo-Platonists of a less critical type than the ancient chiefs of the school. Belief in both magic and astrology, it is hardly nesessary to say, had run down through thewhole course of the intervening centuries; so that there was little as yet in the atmosphere of the modern time that could lead to a renewal of the sceptical and critical sifting begun by thinkers like Plotinus and Porphyry. The influence of Christianity shows itself in the special stress laid on the religious aspect of Neo-Platonism. An example of this is to be met with at the end of Marsilio Ficino's translation of Plotinus. In the arguments prefixed to the closing chapters, Ficino tries to make Plotinus say definitely that the union of the soul with God, once attained, is perpetual. He has himself a feeling that the attempt is not quite successful; and he rather contends that Plotinus was logically bound to make the affirmation than that it is there in his very words. As a matter of fact, Plotinus has nowhere definitely made it; and it seems inconsistent alike with his own position that differences of individuality proceed with necessity from eternal distinctions in the divine intellect, and with his hypothetical use of the Stoic doctrine that events recur in exactly repeated cycles. When he says that in the intelligible world, though not in earthly life, the vision is continuous, this does not by itself mean that the soul, when it has ascended, remains above without recurrent descents. It is true, nevertheless, that Plotinus and Porphyry did not so explicitly as their successors affirm that all particular souls are subject to perpetual vicissitude.

This point is of special interest because Ficino's interpretation may have helped to mislead Bruno, who, in a passage in the dedication of his Eroici Furori to Sir Philip Sidney, classes Plotinus, so far as this doctrine is concerned, with the "theologians." All the great philosophers except Plotinus, he says, have taught that the mutations in the destiny of souls are without term. On the other hand, all the great theologians except Origen have taught that the soul either attains final rest or is finally excluded from beatitude. The latter doctrine has a practical reference, and may be impressed on the many lest they should take things too lightly. The former is the expression of pure truth, and is to be taught to those who are capable of ruling themselves. Great as is for Plotinus the importance of the religious redemption to which his philosophy leads, the theoretic aspect of his system is here misapprehended. Nothing, however, could bring out more clearly than this pointed contrast, Bruno's own view. Coming near the end of Renaissance Platonism, as Ficino comes near its beginning, he marks the declared break with tradition and the effort after a completely independent philosophy.

Other elements as well as Neo-Platonism contributed to Bruno's doctrine; yet he too proceeds in his metaphysics from the Neo-Platonic school. In expression, he always falls back upon its terms. The system, indeed, undergoes profound modifications. Matter and Form, Nature and God, become antithetic names of a single reality, rather than extreme terms in a causal series descending from the highest to the lowest. Side by side with the identity, however, the difference is retained, in order to express the "circle" in phenomenal things. In Bruno's cosmological view, modifications were of course introduced by his acceptance and extension of the Copernican astronomy. Yet he seeks to deduce this also from propositions of the Neo-Platonic metaphysics. The Neo-Platonists held, as he did, that the Cause is infinite in potency, and necessarily produces all that it can produce. The reason why they did not infer that the extended universe is quanti­tatively infinite was that, like some moderns, they thought actual quantitative infinity an impossible conception.

One of Bruno's most interesting points of contact with Plotinus is in his theory of the beautiful. For this he may have got the hint from the difference that had struck Plotinus between the emotion that accompanies pursuit of knowledge and beauty on the one hand, and mystical unification with the good on the other. By this unification, however, Plotinus does not mean moral virtue; so that when Bruno contrasts intellectual aspiration with a kind of stoical indifference to fortune, and treats it as a "defect" in comparison, because there is in the constantly baffled pursuit of absolute truth or beauty an element of pain, he is not closely following Plotinus. Yet in their account of the aspiration itself, the two thinkers agree. The fluctuation and pain in the aesthetic or intellectual life are insisted on by both. In Bruno indeed the thought is immensely expanded from the hint of Plotinus; the Eroici Furori being a whole series of imaginative symbols interpreted as expressive of the same ardour "to the unknown God of unachieved desire." There is here manifest a difference of temperament. Bruno had more of the restlessness which Plotinus finds in the soul of the artist and the theorist. Plotinus, along with his philosophical enthusiasm, had more of the detachment and repose of the religious mystic.

The most striking difference between the Platonism of the Neo-Platonists and that of the Renaissance, is the stronger accentuation by the latter of naturalistic pantheism. This, though not absent in Neo-Platonism itself, is subordinate. Plotinus, as we saw, regards the heavenly bodies as divine, and can on occasion speak like Bruno of the earth as one of the stars. This side of his doctrine, however, is less prominent than his conception of intellectual and superessential divinity. With Bruno the reverse is the case. And Campanella too seizes on the naturalistic side of the doctrine to confound the despisers of the visible world. Among his philosophical poems there is one in particular which conveys precisely the feeling of the book of Plotinus against the Gnostics.

Deem you that only you have thought and sense,

While heaven and all its wonders, sun and earth,

Scorned in your dullness, lack intelligence ?

Fool! what produced you ? These things gave you birth:

So have they mind and Godl.

 

This tone of feeling, characteristic of the Renaissance, passed away during the prevalence of the new "mechanical philosophy," to reappear later when the biological sciences were making towards theories of vital evolution. It is thus no accident that it should then have been rendered by Goethe, who combined with his poetic genius original insight in biology.

While the Platonizing movement was going on, other ancient doctrines had been independently revived. For the growth of the physical sciences, now cultivated afresh after long neglect, the revival of Atomism was especially important. The one scientific doctrine of antiquity which Neo-Platonism had been unable to turn to account was seen by modern physicists to be exactly that of which they were in need. Thus whether, like Descartes and Hobbes, they held that the universe is a plenum, or, with Democritus himself, affirmed the real existence of vacuum, all the physical thinkers of the seventeenth century thought of body, for the purposes of science, as corpuscular. Corpuscular physics was the common foundation of the "mechanical philosophy." Now it is worthy of note that the first distinctively Platonic revival, beyond the period we call the Renaissance, decisively adopted the corpuscular physics as not incompatible with "the true intellectual system of the universe." The Cambridge Platonists, as represented especially by Cudworth, did not, in their opposition to the naturalism of Hobbes, show any reactionary spirit in pure science; but were so much awake to the growing ideas of the time that, even before the great impression made by Newton's work, they were able to remedy for themselves the omission that had limited the scientific resources of their ancient predecessors. And More, in appending his philosophical poem on The Infinity of Worlds to that on The Immortality of the Soul, does not shrink from appealing to the authority of Democritus, Epicurus and Lucretius in favour of those infinite worlds in space which the Neo-Platonists had rejected. Neither on this question nor on the kindred one as to the manifestation of Deity in a phenomenal universe without past or future limit in time, does he commit himself to a final conclusion; but evidently, after at first rejecting both infinities as involving impossibilities of conception, he inclined to the affirmation of both.

The new metaphysical position that philosophy had in the meantime gained, was the subjective point of view fixed by Descartes as the principle of his "method for conducting the reason and seeking truth in the sciences." This, as has been indicated, was remotely Neo-Platonic in origin; for the Neo­Platonists had been the first to formulate accurately those conceptions of immaterial subject and of introspective consciousness which had acquired currency for the later world through the abstract language of the schools. Thus Descartes, with Scholasticism and Humanism behind him, could go in a summary way through the whole process, without immersing himself in one or the other as a form of erudition; and could then start, so far as the problem of knowledge is concerned, where the ancients had left off. Knowledge of that which is within, they had found, is in the end the most certain. The originality of Descartes consisted in taking it as the most certain in the beginning. Having fixed the point of view, he could then proceed, from a few simple positions ostensibly put forward without appeal to authority, to construct a new framework for the sciences of the inner and of the outer world.

Here was the beginning of idealism in its modern form. The other great innovation of the modern world in general principle, was the notion that there is a mode of systematically appealing to experience as the test of scientific truth; that rational deduction, such as was still the main thing for Descartes, must be supplemented by, if not ultimately subordinated to, the test of inductive verification. This, though not exclusively an English idea, has been mainly promoted by English thinkers, in its application first to the physical, and then, still more specially, to the mental sciences. In antiquity, experience had indeed been recognized as the beginning of knowledge in the genetic order. Its priority in this sense could be allowed by a school as rationalist as Neo-Platonism. It had not, however, even by the experiential schools, been rigorously defined as a test applicable to all true science. On this side Bacon and Locke, as on the other side Descartes, were the great philosophical initiators of the new time.

The essential innovations of modern thought, as we see, were innovations in method. They did not of themselves suggest any new answer to questions about ultimate reality or the destiny of the universe. It is not that such answers have been lacking; but they have always remained, in one way or another, new formulations of old ones. The hope cherished by Bacon and Descartes that the moderns might at length cut themselves loose from the past and, by an infallible method, discover all attainable truth, has long been seen to be vain. Not only individual genius, but historical study of past ideas and systems, have become of more and not of less importance. The most original and typical ontologies of modern times are those of Spinoza and Leibniz; and, much as they owe to the newer developments of science and theory of knowledge, both are expressed by means of metaphysical conceptions that had taken shape during the last period of ancient thought. Pantheism and Monadism are not merely implicit in the Neo­Platonic doctrine; they receive clear formulation as different aspects of it. lf, as some modern critics think, the two conceptions are not ultimately irreconcilable, the best hints for a solution may probably still be found in Plotinus. No one has ever been more conscious than he of the difficulty presented by the problem of comprehending as portions of one philosophical truth the reality of universal and that of individual intellect.

Perhaps the strongest testimony to the intrinsic value of the later Greek thought is Berkeley's Siris. For if that thought had really become obsolete, Berkeley was in every way prepared to perceive it. He had pushed the Cartesian reform as far as it would go, by reducing what Descartes still thought of as real extended substance to a system of phenomena for consciousness. He had at the same time all the English regard for the test of experience, fortified by knowledge of what had been done in his own age in investigating nature. Thus, he had taken most decisively the two steps by which modern philosophy has made a definite advance. Besides, as a theologian, he might easily have assumed that anything there was of value in the work of thinkers who, living long after the opening of the Christian era, had been the most uncompromising antagonists of the Christian Church, must have been long superseded. His own early Nominalism, which, as may be seen in Siris itself, he had never abandoned, might also have been expected to prejudice him against Platonic Realism. Yet it is precisely in the Neo-Platonists that Berkeley, near the end of his philosophical career, found hints towards a tentative solution of ontological questions which he had at first thought to settle once for all by a resolutely logical carrying out of the principles of Descartes and Locke. It is true that in actual result Siris makes no advance on the original Neo­Platonic speculations, which are not really fused with Berkeley's own early doctrine, but are at most kept clear of contradiction with it. For all that, Siris furnishes the most decisive evidence of enduring vitality in a school of thought which, to Berkeley's age if to any since the classical revival, must have seemed entirely of the past.

Berkeley's work here seems in a manner comparable with that of the Platonising English poets from Spenser to Shelley. The influence of Platonism on literature is, however, too wide a subject to be treated episodically. The one remark may be made, that not till modern times did it really begin to influence poetic art. In antiquity it had its theories of art—varying greatly, as we have seen, from Plato to Plotinus—but artistic production was never inspired by it. If poetic thought, as some think, is an anticipation of the future, this influence on poetry may be taken as further evidence that the ideas of the philosophy itself are still unexhausted.

During the seventeenth and eighteenth centuries, the great controversies of metaphysics did not centre in Platonism. There is truth in the view that would make this first period of distinctively modern philosophy a kind of continuation of later Scholasticism, more than of the Renaissance which immediately preceded it. Its ostensible questions were about method. The usual division of its schools or phases by historians is into "Dogmatism" (by which is meant the rationalistic theory of certitude) and its opposite "Empiricism," followed by "Scepticism" and then by "Criticism." As these names show, it is concerned less with inquiry into the nature of reality than with the question how reality is to be known, or whether indeed knowledge of it is possible. And, with all its differences, the modern "Enlightenment" has this resemblance to Scholasticism, that a particular system of doctrine is always in the background, to which the controversy is tacitly referred. This system is in effect the special type of theism which the more rationalistic schoolmen undertook to prove as a preliminary to faith in the Catholic creed. Even in its non-Christian form, as with the "Deists," it is still of the Judaeo-Christian tradition. The assumption about the relation of God to the world is that the world was created by an act of will. Ordinary Rationalism is "dogmatic" by its assertion that "natural religion" of this type can be demonstrated. "Empiricism" usually holds that the same general positions can be established sufficiently on at least "probable" grounds. The Scepticism of Hume proceeds to show the failure of Empiricism—with which he sides philosophically as against Rationalism—to establish anything of the kind. Hume's philosophical questioning, while this was the practical reference which aroused so much lively feeling in his own age, had of course a wider reach. Yet when Kant, stirred by the impulse received from Hume, took up again from a "Critical" point of view the whole problem as to the possibility of knowledge, he too thought with a reference to the same practical centre of the controversy. Having destroyed the Wolffian "Dogmatism," he still aimed at reconstructing from its theoretical ruin a generalised theology of essentially the same type. For Kant, as for the line of thinkers closed by him, there was only one ontology formally in question; and that was Christian theism, with or without the Christian revelation.

The German movement at the opening of the nineteenth century, if it did nothing else, considerably changed this aspect of things. In its aims, whatever may now be thought of its results, it was a return to ontology without presuppositions. The limited dogmatic system which was the centre of interest for the preceding period has for the newer speculation passed out of sight. Spinoza perhaps on the positive side exercises a predominant influence; but there are returns also to the thinkers of the Renaissance, to Neo-Platonism, and to the ancient systems of the East, now beginning to be known in Europe from translations of their actual documents. A kind of Nco-Christianity too appears, which again treats Christian dogma in the spirit of the Gnostics or of Scotus Erigena. And all this is complicated by the necessity imposed on every thinker of taking up a definite attitude to the Kantian criticism of knowledge. Among the systems of the time, that of Hegel in particular has frequently been compared to Neo­Platonism; but here the resemblance is by no means close. The character of Hegel's system seems to have been deter­mined mainly by its relation to preceding German philosophy and to Spinoza. Both on Spinoza himself and on Leibniz, the influence of Neo-Platonism, direct or indirect, was much more definite, and points of comparison might be sought with more profit. In Hegel, as in the other philosophers of the period, the resemblance is partly of a quite general kind. They are again ontologists, interested in more possibilities than in the assertion or denial of the rudiments of a single creed. But, knowing the historical position of the Neo-Platonists, they find in them many thoughts that agree with their personal tendencies.

Up to this point the outline given of the course of later philosophy may, it seems to me, on the whole be regarded as abbreviated history. The next stage may perhaps be summed up as another return from ontology to questions about the possibility of knowledge, and to logical and methodological inquiries. To pursue further the attempt to characterise the successive stages of European thought would be to enter the region where no brief summary can fairly pretend to be a deposit of ascertained results. The best plan, from the point now reached, will be to try to state the law of philosophic development which the history of Neo-Platonism suggests; and then to make some attempt to learn what positive value the doctrine may still have for the modern world. This will be the subject of the concluding chapter.