Shortly after the outbreak of the Peloponnesian war Plato was born, probably in 427. During the eighty years of his life he travelled to Sicily at least twice, founded the Academy at Athens and saw the beginning of the end of the Greek freedom. He represents the reflective spirit in a nation which seems to appear when its development is well advanced. After the madness of a long war the Athenians, stripped of their Empire for a time, sought a new outlet for their restless energies and started to conquer a more permanent kingdom, that of scientific speculation about the highest faculties of the human mind.

The death of Socrates in 399 disgusted Plato; democracy apparently was as intolerant as any other form of political creed. His writings are in a sense a vindication of the honesty of his master, although the picture he draws of him is not so true to life as that of Xenophon. The dialogues fall into two well-marked classes; in the earlier the method and inspiration is definitely Socratic, but in the later Socrates is a mere peg on which Plato hung his own system. In itself the dialogue form was no new thing; Plato adopted it and made it a thing of life and dramatic power, his style being the most finished example of exalted prose in Greek literature. The order in which the dialogues were written is a thorny problem; there is good reason for believing that Plato constantly revised some of them, removing the inconsistencies which were inevitable while he was feeling his way to the final form which his speculations assumed. It is perhaps best to give an outline of a series which exhibits some regular order of thought.

It is sometimes thought that Philosophy has no direct bearing on practical questions. A review of the Crito may dispel this illusion. In it Socrates refuses to be tempted by his young friend Crito who offers to secure his escape from prison and provide him a home among his own friends. The question is whether one ought to follow the opinions of the majority on matters of justice or injustice, or those of the one man who has expert knowledge, and of Truth. The laws of Athens have put Socrates in prison; they would say;

Socrates had by his long residence of seventy years declared his satisfaction with the Athenian legal system. The laws had enabled him to live in security; more, he could have taken advantage of legal protection in his trial, and if he had been dissatisfied could have gone away to some other city. What sort of a figure would he make if he escaped? Wherever he went he would be considered a destroyer of law; his practice would belie his creed; finally, the Laws say,

Sound and concrete teaching like this is always necessary, but is hardly likely to be popular. The doctrine of disobedience is everywhere preached in a democracy; violation of contracts is a normal practice and law-breakers have been known to be publicly feasted by the very members of our legislative body.

A different lesson is found in the Euthyphro. After wishing Socrates success in his coming trial, Euthyphro informs him that he is going to prosecute his father for manslaughter, assuring him that it would be piety to do so. Socrates asks for a definition of piety. Euthyphro attempts five—"to act as Zeus did to his father"; "what the gods love"; "what all the gods love"; "a part of righteousness, relating to the care of the gods"; "the saying and doing of what the gods approve in prayer and sacrifice". Each of these proves inadequate; Euthyphro complains of the disconcerting Socratic method as follows:

It is noticeable that no definite result comes from this dialogue; Plato was within his rights in refusing to answer the main question. Philosophy does not pretend to settle every inquiry; her business is to see that a question is raised. Even when an answer is available, she cannot always give it, for she demands an utter abandonment of all prepossessions in those to whom she talks—otherwise there will be no free passage for her teaching. Though refuted, Euthyphro still retained his first opinions, for his first and last definitions are similar in idea. To such a person argument is mere waste of time.

An admirable illustration of Plato's lightness of touch is found in the Laches. The dialogue begins with a discussion about the education of the young sons of Lysimachus and Melesias. Soon the question is raised "What is courage?" Nicias warns Laches about Socrates; the latter has a trick of making men review their lives; his practice is good, for it teaches men their faults in time; old age does not always bring wisdom automatically. Laches first defines courage as the faculty which makes men keep the ranks in war; when this proves inadequate, he defines it as a stoutness of spirit. Nicias is called in; he defines it as "knowledge of terrors and confidence in war"; he is soon compelled to add "and knowledge of all good and evil in every form"—in a word, courage is all virtue combined. The dialogue concludes that it is not young boys but grown men of all ages who need a careful education. This spirited little piece is full of dramatic vigour—the remarks of Laches and Nicias about each other as they are repeatedly confuted are most human and diverting.

Literary criticism is the subject of the Ion. Coming from Ephesus, Ion claimed to be the best professional reciter of Homer in all Greece. Acknowledging that Homer made him all fire, while other poets left him cold, he is made to admit that his knowledge of poetry is not scientific; otherwise he would have been able to discuss all poetry, for it is one. Socrates then makes the famous comparison between a poet and a magnet; both attract an endless chain, and both contain some divine power which masters them. Ecstasy, enthusiasm, madness are the best descriptions of poetic power. Even as a professional reciter Ion admits the necessity of the power of working on men.

Homer is the subject of the Hippias Minor. At Olympia Hippias once said that every single thing that he was wearing was his own handiwork. He was a most inventive person—one of his triumphs being an art of memory. In this dialogue he prefers the Iliad to the Odyssey because Achilles was called "excellent" and Odysseus "versatile". Socrates soon proves to him that Achilles was false too, as he did not always keep his word. He reminds Hippias that he never wastes time over the brainless, though he listens carefully to every man. In fact, his cross-examination is a compliment. He never thinks the knowledge he gains is his own discovery, but is grateful to any who can teach him. He believes that unwitting deceivers are more culpable than deliberate tricksters. Hippias finds it impossible to agree with him, whereupon Socrates says that things are for ever baffling him by their changeability; it is pardonable that unlearned men like himself should err; when really wise people like Hippias wander in thought, it is monstrous that they are unable to settle the doubts of all who appeal to them.

Channides, the young boy after whom the dialogue was named, was the cousin and ward of Critias, the infamous leader of the Thirty Tyrants. On being introduced to him Socrates starts the discussion "What is self-control?" The lad makes three attempts to answer; seeing his confusion, Critias steps in, "angry with the boy, like a poet angry with an actor who has murdered his poems". But he is not more successful; his three definitions are proved wanting.

The dialogue gives no definite answer to the discussion. It is a vivid piece of writing; the contrast between the young lad and the elder cousin whose pet phrases he copies is very striking.

In the Lysis the characters and the conclusion are similar. Lysis is a young lad admired by Hippothales. The first portion of the dialogue consists of a conversation between Lysis and Socrates; the latter recommends the admirer to avoid foolish converse. On the entry of Lysis' friend Menexenus, Socrates starts the question "What is friendship?" It appears that friendship cannot exist between two good or two evil persons, but only between a good man and one who is neither good nor bad, exactly as the philosopher is neither wise nor ignorant, yet he loves knowledge. Still this is not satisfactory; up conclusion being reached, Socrates winds up with a characteristic remark; they think they are friends, yet cannot say what friendship is. This dialogue was carefully read by Aristotle before he gave his famous description in the Ethics: "A friend is a second self". Perhaps Socrates avoided a definite answer because he did not wish to be too serious with these sunny children.

The Euthydemus is an amusing study of the danger which follows upon the use of keen instruments by the unscrupulous. Euthydemus and his brother Dionysodorus are two sophists by trade to whom words mean nothing at all; truth and falsehood are identical, contradiction being an impossibility. As language is meaningless, Socrates himself is quickly reduced to impotence, recovering with difficulty. Plato was no doubt satirising the misuse of the new philosophy which was becoming so popular with young men. When nothing means anything, laughter is the only human language left. The Cratylus is a similarly conceived diversion. Most of it is occupied with fanciful derivations and linguistic discussions of all kinds. It is difficult to say how far Plato is serious. Perhaps the feats of Euthydemus in stripping words of all meaning urged him to some constructive work—for Plato's system is essentially destructive first, then constructive. At any rate, he does insist on the necessity for determining a word's meaning by its derivation, and points out that a language is the possession of a whole people.

In the Protagoras Socrates while a young man is represented as meeting a friend Hippocrates, who was on his way to Protagoras, a sophist from Abdera who had just arrived at Athens. Socrates shows first that his friend has no idea of the seriousness of his action in applying for instruction to a sophist whose definition he is unable to give.

They proceed to the house of Callias, where they find Protagoras surrounded by strangers from every city who listened spell-bound to his voice.

Protagoras readily promises that Hippocrates would be taught his system which offers "good counsel about his private affairs and power to transact and discuss political matters". Socrates' belief that politics cannot be taught provokes one of the long speeches to which Plato strongly objected because a fundamental fallacy could not be refuted at the outset, vitiating the whole of the subsequent argument. Protagoras recounted a myth, proving that shame and justice were given to every man; these are the basis of politics. Further, cities punish criminals, implying that men can learn politics, while virtue is taught by parents and tutors and the State. Socrates asks whether virtue is one or many. Protagoras replies that there are five main virtues, knowledge, justice, courage, temperance and piety, all distinct. A long rambling speech causes Socrates to protest; his method is the short one of question and answer. By using some very questionable reasoning he proves that all these five virtues are identical. Accordingly, if virtue is one it can be taught, not however, by a sophist or the State, but by a philosopher, for virtue is knowledge.

This conclusion is thoroughly in harmony with Socrates' system. Yet it is probably false. Virtue is not mere knowledge, nor vice ignorance. If they were, they would be intellectual qualities. They are rather moral attributes; experience soon proves that many enlightened persons are vicious and many ignorant people virtuous. The value of this dialogue is its insistence upon the unity of virtue. A good man is not a bundle of separate excellences; he is a whole. Possessing one virtue he potentially has them all.

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.

The Phaedo describes Socrates' discussion of the immortality of the soul on his last day on earth. Reminiscence of Ideas proves pre-existence, as in the Meno; the Ideas are similarly used to prove a continued existence after death, for the soul has in it an immortal principle which is the exact contrary of mortality; the Idea of Death cannot exist in a thing whose central Idea is life. Such in brief is Socrates' proof. To us it is singularly unconvincing, as it looks like a begging of the whole question. Yet Plato argues in his technical language as most men do concerning this all-important and difficult question. That which contains within itself the notion of immortality would seem to be too noble to have been created merely to die. The very presence of a desire to realise eternal truth is a strong presumption that there must be something to correspond with it. The most interesting portion of this well-known dialogue is that which teaches that life is really an exercise for death. All the base and low desires which haunt us should be gradually eliminated and replaced by a longing for better things. The true philosopher at any rate so trains himself that when his hour comes he greets death with a smile, the life on earth having lost its attractions.

Such is the connection between the Meno and the Phaedo; the life that was before and the life that shall be hereafter depend upon the Ideal world. That salvation is in this life and in the practical sphere of human government is possible only through a knowledge of these Ideas is the doctrine of the immortal Republic. This great work in ten books is well known, but its unique value is not always recognised. It starts with a discussion of Justice. Thrasymachus, a brazen fellow like Callicles in the Gorgias, argues that Justice is the interest of the stronger and that law and morality are mere conventions. The implications of this doctrine are of supreme importance. If Justice is frank despotism, then the Eastern type of civilisation is the best, wherein custom has once for all fixed the right of the despot to grind down the population, while the sole duty of the latter is to pay taxes. The moral reformation of law becomes impossible; no adjustment of an unchanging decree to the changing and advancing standard of public morality can be contemplated; constitutional development, legal reformation and the great process by which Western peoples have tried gradually to make positive law correspond with Ethical ideals are mere dreams.

But the verbal refutation of Thrasymachus does not satisfy Glaucus and Adeimantus who are among Socrates' audience. In order to explain the real nature of Justice, Socrates is compelled to trace from the very beginning the process by which states have come into existence. Economic and military needs are thoroughly discussed. The State cannot continue unless there is created in it a class whose sole business it is to govern. This class is to be produced by communistic methods; the best men and women are to be tested and chosen as parents, their children being taken and carefully trained apart for their high office. This training will be administered to the three component parts of the soul, the rational, the spirited and the appetitive, while the educational curriculum will be divided into two sections, Gymnastic for the body and Artistic for the mind—the latter including all scientific, mathematical and literary subjects. After a careful search, in this ideal state Justice, the principle of harmony which keeps all classes of the community coherent, will show itself in "doing one's own business".

Yet even this method of describing Justice is not satisfactory to Plato, who was not content unless he started from the universal concepts of the Ideal world. The second portion of the dialogue describes how knowledge is gained. The mind discards the sensible and material world, advancing to the Ideas themselves. Yet even these are insufficient, for they all are interconnected and united to one great and architectonic Idea, that of the Good; to this the soul must advance before its knowledge can be called perfect. This is the scheme of education for the Guardians; the philosophic contemplation of Ideas, however, should be deferred till they are of mature age, for philosophy is dangerous in young men. Having performed their warlike functions of defending the State, the Guardians are to be sifted, those most capable of philosophic speculation being employed as instructors of the others. Seen from the height of the Ideal world, Justice again turns out to be the performance of one's own particular duties.

This ideal society Plato admits to be a difficult aim for our weak human nature; he stoutly maintains, however, that "a pattern of it is laid up in heaven", man's true home. He mournfully grants that a declension from excellence is often possible and describes how this rule of philosophers, if established, would be expected to pass through oligarchy to democracy, the worst form of all government, peopled by the democratic man whose soul is at war with itself because it claims to do as it likes. The whole dialogue ends in an admirable vision in which he teaches that man chose his lot on earth in a preexisting state.

Such is a fragmentary description of this masterpiece. What is it all about? First it is necessary to point out a serious misconception. Plato is not here advocating universal communism; his state postulates a money-making class and a labouring class also. Apart from the fact that he explicitly mentions these and allows them private property, it would be difficult to imagine that they are not rendered necessary by his very description of Justice. Not all men are fit for government—and therefore those who are governed must "do their particular business" for which they are fitted; in some cases it is the rather mean business of piling up fortunes. Communism is advocated as the only means of creating first and then propagating the small Guardian caste. Nor again is the caste rigid, for some of the children born of communistic intercourse will be unfit for their position and will be degraded into the money-making or property owning section. Communism to Plato is a high creed, too high for everybody, fit only for the select and enlightened or teachable few.

Nor is the Republic an instance of Utopian theorising. It is a criticism of contemporary Greek civilisation, intended to remove the greatest practical difficulty in life. Man has tried all kinds of governments and found none satisfactory. All have proved selfish and faithless, governing for their own interests only. Kings, oligarchs, democrats and mob-leaders have without exception regarded power as the object to be attained because of the spoils of office. Political leadership is thus a direct means of self-advancement, a temptation too strong for weak human nature. As a well-known Labour leader hinted, five thousand a year does not often come in men's way. There is only one way of securing honest government and that is Plato's. A definite class must be created who will exercise political power only, economic inclinations of any sort disqualifying any of its members from taking office. The ruling class should rule only, the money-making class make money only. In this way no single section will tax the rest to fill its own pockets. The one requisite is that these Guardians should be recognised as the fittest to rule and receive the willing obedience of the rest. If any other sane plan is available for preserving the governed from the incessant and rapacious demands of tax-collectors, no record of it exists in literature. Practical statesmanship of a high and original order is manifest in the Republic; in England, where the official qualifications for governing are believed to be equally existent in everybody whether trained or untrained in the art of ruling, the Republic, if read at all, may be admired but is sure to be misunderstood.

It seems that Plato's teaching at the Academy raised formidable criticism. The next group of dialogues is marked by metaphysical teaching. The Parmenides is a searching examination of the Ideas. If these are in a world apart, they cannot easily be brought into connection with our world; a big thing on earth and the Idea of Big will need another Idea to comprehend both. Besides, Ideas in an independent existence will be beyond our ken and their study will be impossible. Socrates' system betrays lack of metaphysical practice; at most the Ideas should have been regarded as part of a theory whose value should have been tested by results. This process is exemplified by a discussion of the fundamental opposition between the One and the infinite Many which are instances of it.

This criticism shows the advantage Plato enjoyed in making Socrates the mouthpiece of his own speculations; he could criticise himself as it were from without. He has put his finger on his own weak spot, the question whether the Ideas are immanent or transcendent. The results of this examination were adopted by the Aristotelian school, who suggested another theory of Knowledge.

The Philebus discusses the question whether Pleasure or Knowledge is the chief good. A metaphysical argument which follows that of the Parmenides ends in the characteristic Greek distinction between the Finite and the Infinite. Pleasure is infinite, because it can exist in greater or less degree; there is a mixed life compounded of finite and infinite and there is a creative faculty to which mind belongs. Pleasure is of two kinds; it is sometimes mixed with pain, sometimes it is pure; the latter type alone is worth cultivating and includes the pleasures of knowledge. Yet pleasure is not an end, but only a means to it. It cannot therefore be the Good, which is an end. Knowledge is at its best when it is dealing with the eternal and immutable, but even then it is not self-sufficient—it exists for the sake of something else, the good. This latter is characterised by symmetry, proportion and truth. Knowledge resembles it far more than even pure pleasure.

The Theaetetus discusses more fully the theory of knowledge. It opens with a comparison of the Socratic method to midwifery; it delivers the mind of the thoughts with which it is in travail. The first tentative definition of knowledge is that it is sensation. This is in agreement with the Protagorean doctrine that man is the measure of all things. Yet sensation implies change, whereas we cannot help thinking that objects retain their identity; if knowledge is sensation a pig has as good a claim to be called the measure of all things as a man. Again, Protagoras has no right to teach others if each man's sensations are a law unto him. Nor is the Heracleitean doctrine much better which taught that all things are in a state of flux. If nothing retains the same quality for two consecutive moments it is impossible to have predication, and knowledge must be hopeless. In fact, sensation is not man's function as a reasoning being, but rather comparison. Neither is knowledge true opinion, for this at once demands the demarcation of false opinion or error; the latter is negative, and will be understood only when positive knowledge is determined. Perhaps knowledge is true opinion plus reason; but it is difficult to decide what is gained by adding "with reason", words which may mean either true opinion or knowledge itself, thus involving either tautology or a begging of the question. The dialogue at least has shown what knowledge is not.

Locke, Berkeley and Hume, the eighteenth century sensation philosophers, were similarly refuted by Kant. The mind by its mere ability to compare two things proves that it can have two concepts at least before it at the same time, and can retain them for a longer period than a mere passing sensation implies. Yet the problem of knowledge still remains as difficult as Plato knew it to be.

"Is the Sophist the same as the Statesman and the Philosopher?" Such is the question raised in the Sophist. Six definitions are suggested, all unsatisfactory. The fixed characteristic of the Sophist is his seeming to know everything without doing so; this definition leads straight to the concept of false opinion, a thing whose object both is and is not. "That which is not" provokes an inquiry into what is, Being. Dualism, Monism, Materialism and Idealism are all discussed, the conclusion being that the Sophist is a counterfeit of the Philosopher, a wilful impostor who makes people contradict themselves by quibbling.

The Politicus carries on the discussion. In this dialogue we may see the dying glories of Plato's genius. In his search for the true pastor or king he separates the divine from the human leader; the true king alone has scientific knowledge superior to law and written enactments which men use when they fail to discover the real monarch. This scientific knowledge of fixed and definite principles can come only from Education. A most remarkable myth follows, which is practically the Greek version of the Fall. The state of innocence is described as preceding a decline into barbarism; a restoration can be effected only by a divine interposition and by the growth of a study of art or by the influence of society. The arts themselves are the children of a supernatural revelation.

The Timaeus and the long treatise the Laws criticise the theories of the Republic. The former is full of world-speculations of a most difficult kind, the latter admits the weakness of the Ideal State, making concessions to inevitable human failings.

Though written in an early period, the Apology may form a fitting end to these dialogues. Socrates was condemned on the charge of corrupting the Athenian youth and for impiety. To most Athenians he must have been not only not different from the Sophists he was never weary of exposing, but the greatest Sophist of them all. He was unfortunate in his friends, among whom were Critias the infamous tyrant and Alcibiades who sold the great secret. The older men must have regarded with suspicion his influence over the youth in a city which seemed to be losing all its national virtues; many of them were personally aggrieved by his annoying habit of exposing their ignorance. He was given a chance of escape by acknowledging his fault and consenting to pay a small fine. Instead, he proposed for himself the greatest honour his city could give any of her benefactors, public maintenance in the town-hall.

His defence contains many superb passages and is a masterpiece of gentle irony and subtle exposure of error. Its conclusion is masterly.

Two lessons of supreme importance are to be learned from Plato. In the first place he insists on credentials from the accepted teachers of a nation. On examination most of them, like Gorgias, would be found incapable of defining the subjects for the teaching of which they receive money. The sole hope of a country is Education, for it alone can deliver from ignorance, a slavery worse than death; the uneducated person is the dupe of his own passions or prejudices and is the plaything of the horde of impostors who beg for his vote at elections or stampede him into strikes.

Again, the possibility of knowledge depends upon accurate definition and the scientific comparisons of instances. These involve long and fatiguing thought and very often the reward is scanty enough; no conclusion is possible sometimes except that it is clear what a thing cannot be. The human intelligence has learned a most valuable lesson when it has recognised its own impotence at the outset of an inquiry and its own limitations at the end thereof. Knowledge, Good, Justice, Immortality are conceptions so mighty that our tiny minds have no compasses to set upon them. Better far a distrust in ourselves than the somewhat impudent and undoubtedly insistent claim to certitude advanced by the materialistic apostles of modern non-humanitarianism. When questioned about the ultimates all human knowledge must admit that it hangs upon the slender thread of a theory or postulate. The student of philosophy is more honest than others; he has the candour to confess the assumptions he makes before he tries to think at all.

At times it must be admitted that Plato sounds very unreal. His faults are clear enough. The dialogue form makes it very easy for him to invent questions of such a nature that the answer he wants is the only one possible. Again, his conclusions are often arrived at by methods or arguments which are frankly inadmissible; in the earlier dialogues are some very glaring instances of sheer logical worthlessness. Frequently the whole theme of discussion is such that no modern philosopher could be expected to approve of it. A supposed explanation of a difficulty is sometimes afforded by a myth, splendid and poetical but not logically valid. Inconsistencies can easily be pointed out in the vast compass of his speculations. It remained for Aristotle to invent a genuine method of sorting out a licit from an illicit type of argument.

These faults are serious. Against them must be placed some positive excellences. Plato was one of the first to point out that there is a problem; a question should be asked and an answer found if possible, for we have no right to take things for granted. More than this, he was everywhere searching for knowledge, ridding himself of prejudice, doing in perfect honesty the most difficult of all things, the duty of thinking clearly. These thoughts he has expressed in the greatest of all types of Greek prose, a blend of poetic beauty with the precision of prose.

But Plato's praise is not that he is a philosopher so much as Philosophy itself in poetic form. His great visions of the Eternal whence we spring, his awe for the real King, the real Virtue, the real State "laid up in Heaven" fill him with an inspired exaltation which lifts his readers to the Heaven whence Platonism has descended. There are two main types of men. One is content with the things of sense; using his powers of observation and performing experiments he will become a Scientist; using his powers of speculation he will become an Aristotelian philosopher; putting his thoughts into simple and logical order, he will write good prose. The other soars to the eternal principles behind this world, the deathless forms or the general concepts which give concrete things their existence. These perfect forms are the main study of the Artist, Poet, Sculptor, whose work it is to give us comfort and pleasure unspeakable. So long as man lives, he must have the perfection of beauty to gladden him, especially if Science is going to test everything by the ruler or balance or crucible. This love of Beauty is exactly Platonism. It has never died yet. From Athens it spread to Alexandria, there to start up into fresh life in the School of which Plotinus is the chief; its doctrines are described for the English reader in Kingsley's Hypatia. It planted its seed of mysticism in Christianity, with which it has most strange affinities. At the Renaissance this mystic element caught the imagination of northern Europe, notably Germany. Passing to England, it created at Cambridge a School of Platonists, the issue of whose thought is evident in the poetry of Coleridge and Wordsworth. Its last outburst has been the Transcendental teaching of the nineteenth century, so curiously Greek and non-Greek in its essence.

For there is in our nature that undying longing for communion with the Divine which the mere thought of God stirs within us. Our true home is in the great world where Truth is everything, that Truth which one day we, like Plato, shall see face to face without any quailing.

TRANSLATIONS:

The version in 4 volumes by Jowett (Oxford) is the standard. It contains good introductions.

The Republic has been translated by Davies and Vaughan.

Two volumes in the Loeb Series have appeared.

A new method of translation of Plato is needed. The text should be clearly divided into sections; the steps of the argument should be indicated in a skeleton outline. Until this is done study of Plato is likely to cause much bewilderment.

Plato and Platonism, by Pater, is still the best interpretation of the whole system.