The Gorgias is a refutation of three distinct and popular notions. Gorgias of Leontini used to invite young men to ask him questions, none of whom ever put to him a query absolutely new. It soon appears that he is quite unable to define Rhetoric, the art by which he lived. Socrates said it was a minister of persuasion, that it in the long run concerned itself with mere Opinion, which might be true or false, and could not claim scientific Knowledge. Further, it implied some morality in its devotees, for it dealt with what was just or unjust. Polus, a young and ardent sophist, was compelled to assent to two very famous doctrines, first that it is worse to do evil than to experience it, second, that to avoid punishment was the worst thing for an offender. But a more formidable adversary remained, one Callicles, the most shameless and unscrupulous figure perhaps in Plato's work. His creed is a flat denial of all authority, moral or intellectual. It teaches that Law is not natural, but conventional; that only a slave puts up with a wrong, and only weak men seek legal protection. Philosophy is fit only for youths, for philosophers are not men of the world. Natural life is unlimited self-indulgence and public opinion is the creation of those who are too poor to give rein to their appetites; the good is pleasure and infinite self-satisfaction is the ideal. Socrates in reply points out the difference between the kinds of pleasures, insists on the importance of Scientific knowledge of everything, and proves that order is requisite everywhere—its visible effects in the soul being Justice and Wisdom, not Riot. To prevent injustice some art is needed to make the subject as like as possible to the ruler; the type of life a man leads is far more important than length of days. The demagogue who like Callicles has no credentials makes the people morally worse, especially as they are unable to distinguish quacks from wise men. Nor need philosophers trouble much about men's opinions, for a mob always blames the physician who wishes to save it. A delightful piece of irony follows, in which Socrates twits Callicles for accusing his pupils of acting with injustice, the very quality he instils into them. Callicles, though refuted, advises Socrates to fawn on the city, for he is certain to be condemned sooner or later; the latter, however, does not fear death after living righteously.
Most men have held doctrines similar to those refuted here. There is an idea abroad that what is "natural" must be intrinsically good, if not godlike. But it is quite clear that "Nature" is a vague term meaning little or nothing—it is higher or lower and natural in both forms. Those who wish to know the lengths of impudence to which belief in the sacredness of "Nature" can bring human beings might do worse than read the Gorgias.
Plato's dramatic power and fertility of invention are displayed fully in the Symposium. Agathon had won the tragic prize and invited many friends to a wine-party. After a slight introduction a proposition was carried that all should speak in praise of Love. First a youth Phaedrus describes the antiquity of love and gives instances of the attachments between the sexes. Pausanias draws the famous distinction between the Heavenly and the Vulgar Aphrodite; the true test of love is its permanence. A doctor, Eryximachus, raises the tone of the discussion still further. To him Love is the foundation of Medicine, Music, Astronomy and Augury. Aristophanes tells a fable of the sexes in true comic style, making each of them run about seeking its other half. Agathon colours his account with a touch of tragic diction. At last it is Socrates' turn. He tells what he heard from a priestess called Diotima. Love is the son of Fulness and Want; he is the intermediary between gods and men, is active, not passive; he is desire for continuous possession of excellent things and for beautiful creation which means immortality, for all men desire perpetual fame which can come only through the science of the Beautiful. In contemplation and mystical union with the Divine the soul finds its true destiny, satisfying itself in perfect love.
At this moment Alcibiades arrives from another feast in a state of high intoxication. He gives a most marvellous account of Socrates' influence over him and likens him in a famous passage to an ugly little statue which when opened is all gold within. At the end of the dialogue one of the company tells how Socrates compelled Aristophanes and Agathon to admit that it was one and the same man's business to understand and write both tragedy and comedy—a doctrine which has been practised only in modern drama.
In this dialogue we first seem to catch the voice of Plato himself as distinct from that of Socrates. The latter was undoubtedly most keenly interested in the more human process of questioning and refuting, his object being the workmanlike creation of exact definitions. But Plato was of a different mould; his was the soaring spirit which felt its true home to be the supra-sensible world of Divine Beauty, Immortality, Absolute Truth and Existence. Starting with the fleshly conception of Love natural to a young man, he leads us step by step towards the great conclusion that Love is nothing less than an identification of the self with the thing loved. No man can do his work if he is not interested in it; he will hate it as his taskmaster. But when an object of pursuit enthrals him it will intoxicate him, will not leave him at peace till he joins his very soul with it in union indissoluble. This direct communication of Mind with the object of worship is Mysticism. It is the very core of the highest form of religious life; it purifies, ennobles, and above all it inspires. To the mystic the great prophet is the Athenian Plato, whose doctrine is that of the Christian "God is love" converted into "Love is God". It is not entirely fanciful to suggest that Plato, in saying farewell to the definitely Socratic type of philosophy, gave his master as his parting gift the greatest of all tributes, a dialogue which is really the "praise of Socrates".
The intoxication of Plato's thought is evident in the Phaedrus. This splendid dialogue marks even more clearly the character of the new wine which was to be poured into the Socratic bottles. Phaedrus and Socrates recline in a spot of romantic beauty along the bank of the Ilissus. Phaedrus reads a paradoxical speech supposed to be written by Lysias, the famous orator, on Love; Socrates replies in a speech quite as unreal, praising as Lysias did him who does not love. But soon he recants—his real creed being the opposite. Frenzy is his subject—the ecstasy of prophecy, mysticism, poetry and the soul. This last is like a charioteer driving a pair of horses, one white, the other black. It soars upwards to the region of pure beauty, wisdom and goodness; but sometimes the white horse, the spirited quality of human nature, is pulled down by the black, which is sensual desire, so that the charioteer, Reason, cannot get a full vision of the ideal world beyond all heavens. Those souls which have partially seen the truth but have been dragged down by the black steed become, according to the amount of Beauty they have seen, philosophers, kings, economists, gymnasts, mystics, poets, journeymen, sophists or tyrants. The vision once seen is never quite forgotten, for it can be recovered by reminiscence, so that by exercise each man can recall some of its glories.
The dialogue then passes to a discussion of good and bad writing and speaking. The truth is the sole criterion of value, and this can be obtained only by definition; next there must be orderly arrangement, a beginning, a middle and an end. In rhetoric it is absolutely essential for a man to study human nature first; he cannot hope to persuade an audience if he is unaware of the laws of its psychology; not all speeches suit all audiences. Further, writing is inferior to speaking, for the written word is lifeless, the spoken is living and its author can be interrogated. It follows then that orators are of all men the most important because of the power they wield; they will be potent for destruction unless they love the truth and understand human nature; in short, they must be philosophers.
The like of this had nowhere been said before. It opened a new world to human speculation. First, the teaching about oratory is of the highest value. Plato's quarrel with the sophists was based on their total ignorance of the enormous power they exercised for evil, because they knew not what they were doing. They professed to teach men how to speak well, but had no conception of the science upon which the art of oratory rests. In short, they were sheer impostors. Even Aristotle had nothing to add to this doctrine in his treatise on Rhetoric, which contains a study of the effects which certain oratorical devices could be prophesied to produce, and provides the requisite scientific foundation. Again, the indifference to or the ridicule of truth shown by some sophists made them odious to Plato. He would have none of their doctrines of relativity or flux. Nothing short of the Absolute would satisfy his soaring spirit. He was sick of the change in phenomena, the tangible and material objects of sense. He found permanence in a world of eternal ideas. These ideas are the essence of Platonism. They are his term for universal concepts, classes; there are single tangible trees innumerable, but one Ideal Tree only in the Ideal world beyond the heavens. Nothing can possibly satisfy the soul but these unchanging and permanent concepts; it is among them that it finds its true home. Lastly, the tripartite division of the nature of the soul here first indicated is a permanent contribution to philosophy. Thus Plato's system is definitely launched in the Phaedrus. His subsequent dialogues show how he fitted out the hulk to sail on his voyages of discovery.
The Meno is a rediscussion on Platonic principles of the problem of the Protagoras: can virtue be taught? Meno, a general in the army of the famous Ten Thousand, attempts a definition of virtue itself, the principle that underlies specific kinds of virtues such as justice. After a cross-examination he confesses his helplessness in a famous simile: Socrates is like the torpedo-fish which benumbs all who touch it. Then the real business begins. How do we learn anything at all? Socrates says by Reminiscence, for the soul lived once in the presence of the ideal world; when it enters the flesh it loses its knowledge, but gradually regains it. This theory he dramatically illustrates by calling in a slave whom he proves by means of a diagram to know something of geometry, though he never learned it. Thus the great lesson of life is to practise the search for knowledge—and if virtue is knowledge it will be teachable.
But the puzzle is, who are the teachers? Not the sophists, a discredited class, nor the statesmen, who cannot teach their sons to follow them. Virtue then, not being teachable, is probably not the result of knowledge, but is imparted to men by a Divine Dispensation, just as poetry is. But the origin of virtue will always be mysterious till its nature is discovered beyond doubt. So Plato once more declares his dissatisfaction with a Socratic tenet which identified virtue with knowledge.