Schopenhauer is not one of the philosophers who have founded a school, though he has had many disciples and enthusiastic admirers. The pessimism that was for a time a watchword with certain literary groups has passed as a mode, and his true significance must be sought elsewhere. Of the thinkers who have followed him in his pessimism, two indeed stand out as the architects of distinct systems, Eduard von Hartmann and Philipp Mainländer (both already incidentally referred to); but while they are to be classed unquestionably as philosophers, their systems contain an element that their master would have regarded as mythological. Schopenhauer declared as clearly as any of the Greeks that the phenomenal world is without beginning and without end. Kant's positing of an 'antinomy' on this point he regarded as wholly without rational justification. What Kant calls the 'antithesis,' namely, the infinite series, can be logically proved for phenomena. The 'thesis,' which asserts a beginning in time, is defended by mere fallacies. Now Hartmann and Mainländer both hold, though in different fashions, that there is a world-process from a beginning to an end, namely, the extinction of consciousness. This is the redemption of the world. Their affinity, therefore, seems to be with the Christian Gnostics rather than with the pure philosophers of the Greek tradition, continued in modern times by Bruno, Spinoza, and Schopenhauer.
Whatever may be thought of the pessimism by which Schopenhauer's mood is distinguished from that of his precursors, few will fail to recognise that special doctrines of his system contain at least a large portion of truth. His theories of Art, of Genius, and of Love are enough to found an enduring reputation for any thinker, even if there were nothing else of value in his writings. But there is much else, both in systematic construction and in the illumination of detail. I have been inclined to put forward first of all the translation into idealistic terms of the universal sentiency held by the Ionian thinkers to be inherent in the primordial elements of nature. While they viewed the world as an objective thing having psychological qualities, Schopenhauer, after the long intermediate process of thought, could treat it as phenomenal object with a psychological or subjective essence. For both doctrines alike, however, mind or soul is immanent. Still, it must be allowed that a difference remains by which Schopenhauer was even more remote than they were from the later Greek idealism. As they were not materialists, so they did not exclude reason from the psychical properties of their substances. Schopenhauer, while he rejected the materialism of their ancient and modern successors alike, took the step of formally derationalising the elements of mind. This, no doubt, is unsustainable ultimately, if reason is ever to emerge from them. Yet the one-sidedness of the position has had a peculiar value in combating an equally one-sided rationalistic idealism. This is recognised by clear-sighted opponents. And Schopenhauer's calling the non-rational or anti-rational element in the world 'will' helps to make plainer the real problem of evil. There is truth in the Hegelian paradox that 'pessimism is an excellent basis for optimism.' An optimist like Plotinus saw that, even if good comes of evil, the case of the optimist must fail unless evil can be shown to be a necessary constituent of the world. The Platonic and Neo-Platonic 'matter,' a principle of diremption or individuation, like time and space for Schopenhauer, was an attempt to solve this problem; but something more positive seemed to be needed as the source of the stronger manifestations of evil. To the strength of these Plato drew attention in a passage (_Republic_, x. 610[5]) where it is acknowledged that injustice confers a character of vitality and sleeplessness upon its possessor. In the notion of a blind and vehement striving, Schopenhauer supplies something adequate; only, to maintain a rational optimism, it must be regarded as a necessary element in a mixture, not as the spring of the whole.