4:38 PHILOSOPHY originally chaotic and formless, but along with this is the ideal world. The cosmos was pro- duced by the best artificer, the moving deliber- ative principle, after an eternal pattern. Pla- to's explanation of nature, in contrast with the earlier ones, is thoroughly teleological. The human soul, kindred to the world-soul, which mediates ideas, and is the invisible dynamical principle of order and motion, is a dualism of forces, the one culminating in the pure thought of reason, the other impulsive and gravitating downward, thus attesting man's apostasy from his preexistent state. Of this state, by a pure and reasonable life, he awakens reminiscences, and by it also he may hope to escape the evil, and attain to the blessedness of those whose lives please God. Plato's life is marked by three stages of philosophical progress. To the last belongs his founding of the Academy, and the application of his principles to nature and the state. His philosophy, when not identified with dialectic, as it sometimes is, is reached by it ; for this discriminates ; it teaches to divide and to combine ; and beneath the tangible and visible, which are but shadows of the reality, it searches out the true and real. By dialectic the soul attains to true knowledge ; it is eman- cipated from its bondage to body and to sense, and restored to its preexistent perfection. While Plato esteemed only abstract types, Aris- totle laid stress on concrete individualities, as- sailed the theory of ideas as baseless and fantas- tic, and proposed instead the theory of causes. He recognized four metaphysical causes or prin- ciples, matter, form, motive power, and end, which all resolve themselves into the funda- mental antithesis of matter and form. The form, which is life, being added to matter, to which also is ascribed an element of desire, transforms potentiality into actuality ; thus a statue results from matter in the quarry and form in the mind of the artist, and nature is but an evolution of the forms of divine intelli- gence. These forms, unlike the Platonic ideas, are not accomplished, self-subsistent, and per- manent entities, but constitute at once an eternal energy or entelechy and its eternal product. The actual does not follow, but co- incides with the potential ; the form or essence of nature is nothing else than the way to na- ture, its realizing activity and also its proper end. The ideal and real elements which Plato had set apart were thus closely bound together. Forms, as motive principles pervading the universe, have their source in God the first mover, who is being in perfect activity, and bears nothing in himself which is merely po.- tential. As Platonism culminated in the con- ception of ideas, Aristotelianism culminated in that of motion, energy, or life, working in all things, and the ground of their existence and development. Reality belongs only to particulars ; complete knowledge requires com- plete experience; but all possible determina- tions of being are contained in ten categories, their relation to which may be discovered by syllogistic reasoning. The Aristotelian sys- tem of logic was scarcely improved until the present century. The systems of Plato and Aristotle (often designated respectively as the academic and the peripatetic philosophy) are illustrious examples of the ideal and real, or a priori and a posteriori schools, which have existed in every age of speculation. The de- cline of the Greek spirit and civilization was marked by three systems of philosophy, con- ceived with indifference to speculative truth. The skepticism of Pyrrho denied the possibil- ity of certitude concerning anything objective, and proposed a thoughtless and aimless acqui- escence in the impulses of nature as the law of life. His system was maintained by the leaders of the new academy, Arcesilaus and Carneades, and anticipated the absolute doubt of JEnesidemus and Sextus Empiricus. Epi- curus proposed as the goal of philosophy a scheme of morals that should inevitably lead to happiness. The aim of his physics was to rid mankind of the terrors that come from belief in God and immortality, and the aim of his logic was to banish the troubles that come from error. The universe is an aggregation of atoms, moving by chance ; the soul termi- nates with death ; and in a remote space the gods lead a changeless, careless life, ignoring all management of things. Plutarch reproached this system with total sterility of great men and great actions. Stoicism, on the contrary, was recommended by its heroes. Founded by Zeno, a native of Cyprus, and developed by Cleanthes and Chrysippus, it sought to establish a disci- pline of virtue in an age of degeneracy. As- suming that all the materials of knowledge are furnished by sense, it maintained that assent or the free exercise of reason is also required to constitute opinion, and thus proposed a sub- jective criterion of truth. Nature is composed of passive matter and active ruling reason, and to live harmoniously with nature or conform- ably to reason is the moral law. Intellectual or rational existence is thus alone recognized ; passions, pleasures, and pains are to be ignored and despised. The Romans, to whom the re- sults of the Greek schools were made known by Cicero, originated nothing in the progress of philosophy. Epicureanism was represent- ed among them by Lucretius, and stoicism by Seneca, Epictetus, and Marcus Aurelius, but neither acquired new speculative elements ; the former inspired the lower, and the latter, which was an anticipation of the national genius, inspired the higher qualities of Roman life. Seeking only a rule of conduct and gov- ernment, excelling only in the arts of legisla- tion, the Romans aimed to apply rather than discover principles, and borrowed the ideas not only of Greece, but also, through the Ptole- mies and Seleucidae, of Egypt and Asia. The Alexandrian school originated in the collision of Christian, Jewish, and pagan thought. Its problem, suggested by Philo Judaeus, and by oriental dualism, which ascribed evil to mat-
