It was not till Plato arose that a more complete system of philosophy was founded. He was born of noble Athenian parents B.C. 429, the year that Pericles died, and the second year of the Peloponnesian War, and the most active period of Grecian thought. He had a severe education, studying poetry, music, rhetoric, and blending these with philosophy. He was only twenty when he found out Socrates, with whom he remained ten years, and from whom he was separated only by death. He then went on his travels, visiting every thing worth seeing in his day, especially in Egypt. When he returned, he commenced to teach the doctrines of his master, which he did, like him, gratuitously, in a garden near Athens, planted with lofty plane-trees, and adorned with temples and statues. This was called the Academy, and gave a name to his system of philosophy. And it is this only with which we have to do. It is not the calm, serious, meditative, isolated man that I would present, but his contribution to the developments of philosophy on the principles of his master. And surely no man ever made a richer contribution. He may not have had the originality or breadth of Socrates, but he was more profound. He was preeminently a great thinker—a great logician—skilled in dialectics, and his "Dialogues" are such exercises of dialectical method that the ancients were divided whether he was a skeptic or a dogmatist. He adopted the Socratic method, and enlarged it. "Socrates relied on inductive reasoning, and on definitions, as the two principles of investigation. Definitions form the basis of all philosophy. To know a thing, you must know what it is not. Plato added a more efficient process of analysis and synthesis, of generalization and classification." [Footnote: Lewes, Biog. Hist. of Philos.] "Analysis," continues the same author, "as insisted on by Plato, is the decomposition of the whole into its separate parts—is seeing the one in many. Definitions were to Plato, what general or abstract ideas were to later metaphysicians. The individual thing was transitory; the abstract idea was eternal. Only concerning the latter could philosophy occupy itself. Socrates, insisting on proper definitions, had no conception of the classification of those definitions which must constitute philosophy. Plato, by the introduction of this process, shifted philosophy from the ground of inquiries into man and society, which exclusively occupied Socrates, to that of dialectics." Plato was also distinguished for skill in composition. Dionysius of Halicarnassus classes him with Herodotus and Demosthenes in the perfection of his style, which is characterized by great harmony and rhythm, as well as the variety of elegant figures. [Footnote: See Donaldson's quotations, Hist. Lit. of Greece, vol. ii. p. 257.]
[Sidenote: His doctrines.]
[Sidenote: The end of science is the contemplation of truth.]
Plato made philosophy to consist in the discussion of general terms, or abstract ideas. General terms were synonymous with real existences, and these were the only objects of philosophy. These were called Ideas; and ideas are the basis of his system, or rather the subject matter of dialectics. He was a Realist, that is, he maintained that every general term, or abstract idea, has a real and independent existence. Here he probably was indebted to Pythagoras, for Plato was a master of the whole realm of philosophical speculation; but his conception of ideas is a great advance on the conception of numbers. He was taught by Socrates that beyond this world of sense, there was the world of eternal truth, and that there were certain principles concerning which there could be no dispute. The soul apprehends the idea of goodness, greatness, etc. It is in the celestial world that we are to find the realm of ideas. Now God is the supreme idea. To know God should be the great aim of life. We know him by the desire which like feels for like. The divinity within feels for the divinity revealed in beauty, or any other abstract idea. The longing of the soul for beauty is Love. Love then is the bond which unites the human to the divine. Beauty is not revealed by harmonious outlines which appeal to the senses, but is Truth. It is divinity. Beauty, truth, love, these are God, the supreme desire of the soul to comprehend, and by the contemplation of which the mortal soul sustains itself, and by perpetual meditation becomes participant in immortality. The communion with God presupposes immortality. The search for the knowledge of God is the great end of life. Wisdom is the consecration of the soul to the search; and this is effected by dialectics, for only out of dialectics can correct knowledge come. But man, immersed in the flux of sensualities, can never fully attain this high excellence—the knowledge of God, the object of all rational inquiry. Hence the imperfection of all human knowledge. The supreme good is attainable; it is not attained. God is the immutable good, and justice the rule of the universe. "The vital principle of his philosophy is to show that true science is the knowledge of the good; is the eternal contemplation or truth, or ideas; and though man may not be able to apprehend it in its unity, because he is subject to the restraints of the body, he is, nevertheless, permitted to recognize it, imperfectly, by calling to mind the eternal measure of existence, by which he is in his origin connected." [Footnote: Ritter, Hist, of Phil., b. viii. p. 2, chap. i.] He was unable to find a transition from his world of ideas to that of sense, and his philosophy, vague and mystical, though severely logical, diverts the mind from the investigations of actual life—from that which is the object of experience.
[Sidenote: The object of Plato's inquiries.]
The writings of Plato have come down to us complete, and have been admired by all ages for their philosophical acuteness, as well as beauty of language. He was not the first to use the form of dialogue, but he handled it with greater mastery than any one who preceded him, or has come after him, and all with a view to bring his hearers to a consciousness of knowledge or ignorance. He regarded wisdom as the attribute of the godhead; that philosophy is the necessity of the intellectual man, and the greatest good to which he can attain. This wisdom presupposes, however, a communion with the divine. He regarded the soul as immortal and indestructible. He maintained that neither happiness nor virtue can consist in the attempt to satisfy our unbridled desires; that virtue is purely a matter of intelligence; that passions disturb the moral economy.
[Sidenote: God the immutable good.]
"When we review the doctrines of Plato, it is impossible to deny," says Hitter, "that they are pervaded with a grand view of life and the universe. This is the noble thought which inspired him to say, that God is the constant and immutable good; the world is good in a state of becoming, and the human soul that in and through which the good in the world is to be consummated. In his sublimer conception, he shows himself the worthy disciple of Socrates. His merit lies chiefly in having advanced certain distinct and precise rules for the Socratic method, and in insisting, with a perfect consciousness of its importance, upon the law of science, that to be able to descend from the higher to the lower ideas by a principle of the reason, and reciprocally from the multiplicity of the lower to the higher, is indispensable to the perfect possession of any knowledge. He thus imparted to this method a more liberal character. While he adopted many of the opinions of his predecessors, and gave due consideration to the results of the earlier philosophy, he did not allow himself to be disturbed by the mass of conflicting theories, but breathed into them the life-giving breath of unity. He may have erred in his attempts to determine the nature of good; still he pointed out to all who aspire to a knowledge of the divine nature, an excellent road by which they may arrive at it."
Plato is very much admired by the Germans, who look upon him as the incarnation of dialectical power; but it were to be hoped that, some day, these great metaphysicians may make a clearer exposition of his doctrines, and of his services to philosophy, than they have as yet done. To me, Ritter, Brandis, and all the great authorities, are obscure. But that Plato was one of the greatest lights of the ancient world, there can be no reasonable doubt. Nor is it probable that, as a dialectician, he has ever been surpassed; while his purity of life, and his lofty inquiries, and his belief in God and immortality, make him, in an ethical point of view, the most worthy of the disciples of Socrates. He was to the Greeks what Kant was to the Germans, and these two great thinkers resemble each other in the structure of their minds and their relations to society.
The ablest part of the lectures of Archer Butler of Dublin, is devoted to the Platonic philosophy. It is a criticism and an eulogium. No modern writer has written more enthusiastically of what he considers the crowning excellence of the Greek philosophy. The dialectics of Plato, his ideal theory, his physics, his psychology, and his ethics, are most ably discussed, and in the spirit of a loving and eloquent disciple. He represents the philosophy which he so much admires as a contemplation of, and the tendency to, the absolute and eternal good. The good is enthroned by Plato in majesty supreme at the summit of the whole universe, and the sensible world is regarded as a development of supreme perfection in an inferior and transitory form. Nor are ideas abstractions, as some suppose, but archetypal conceptions of the divine mind itself—the eternal laws and reasons of things. The sensible world is regarded as an imperfect image of ideal perfection, yet the uncertainty of physical researches is candidly admitted. The discovery of theological and moral truth, is the great object even of the "Timoeus." Hence the physics of Plato have a theological character—are mathematical rather than experimental. The psychology represents the body as the prison of the soul, somewhat after the spirit of oriental theogonists, and the aim of virtue is to preserve the distinctness of both, and realize liberty in bonds. The doctrine of preexistence is maintained, as well as a future state. In the ethics, the perfection of the human soul—the perfection which it may attain—is distinctly unfolded, and also the unity of the great ideas of the beautiful, just, and good. The "Phoedo" enforces the supremacy of wisdom, and the "Philebus" the "summum bonum." Love is the aspiration after a communion with perfection. The chief excellence of the philosophy which Plato taught, consists in the immutable basis assigned to the principles of moral truth; the defects are a want of distinct apprehension of the claims of divine justice in consequence of human sin, and an indirect discouragement of active virtue.