Again, Plato may be regarded as the 'captain' ('arhchegoz') or leader of a goodly band of followers; for in the Republic is to be found the original of Cicero's De Republica, of St. Augustine's City of God, of the Utopia of Sir Thomas More, and of the numerous other imaginary States which are framed upon the same model. The extent to which Aristotle or the Aristotelian school were indebted to him in the Politics has been little recognised, and the recognition is the more necessary because it is not made by Aristotle himself. The two philosophers had more in common than they were conscious of; and probably some elements of Plato remain still undetected in Aristotle. In English philosophy too, many affinities may be traced, not only in the works of the Cambridge Platonists, but in great original writers like Berkeley or Coleridge, to Plato and his ideas. That there is a truth higher than experience, of which the mind bears witness to herself, is a conviction which in our own generation has been enthusiastically asserted, and is perhaps gaining ground. Of the Greek authors who at the Renaissance brought a new life into the world Plato has had the greatest influence. The Republic of Plato is also the first treatise upon education, of which the writings of Milton and Locke, Rousseau, Jean Paul, and Goethe are the legitimate descendants. Like Dante or Bunyan, he has a revelation of another life; like Bacon, he is profoundly impressed with the unity of knowledge; in the early Church he exercised a real influence on theology, and at the Revival of Literature on politics. Even the fragments of his words when 'repeated at second-hand' (Symp. 215 D) have in all ages ravished the hearts of men, who have seen reflected in them their own higher nature. He is the father of idealism in philosophy, in politics, in literature. And many of the latest conceptions of modern thinkers and statesmen, such as the unity of knowledge, the reign of law, and the equality of the sexes, have been anticipated in a dream by him.
The argument of the Republic is the search after Justice, the nature of which is first hinted at by Cephalus, the just and blameless old man—then discussed on the basis of proverbial morality by Socrates and Polemarchus—then caricatured by Thrasymachus and partially explained by Socrates—reduced to an abstraction by Glaucon and Adeimantus, and having become invisible in the individual reappears at length in the ideal State which is constructed by Socrates. The first care of the rulers is to be education, of which an outline is drawn after the old Hellenic model, providing only for an improved religion and morality, and more simplicity in music and gymnastic, a manlier strain of poetry, and greater harmony of the individual and the State. We are thus led on to the conception of a higher State, in which 'no man calls anything his own,' and in which there is neither 'marrying nor giving in marriage,' and 'kings are philosophers' and 'philosophers are kings;' and there is another and higher education, intellectual as well as moral and religious, of science as well as of art, and not of youth only but of the whole of life. Such a State is hardly to be realized in this world and quickly degenerates. To the perfect ideal succeeds the government of the soldier and the lover of honour, this again declining into democracy, and democracy into tyranny, in an imaginary but regular order having not much resemblance to the actual facts. When 'the wheel has come full circle' we do not begin again with a new period of human life; but we have passed from the best to the worst, and there we end. The subject is then changed and the old quarrel of poetry and philosophy which had been more lightly treated in the earlier books of the Republic is now resumed and fought out to a conclusion. Poetry is discovered to be an imitation thrice removed from the truth, and Homer, as well as the dramatic poets, having been condemned as an imitator, is sent into banishment along with them. And the idea of the State is supplemented by the revelation of a future life.
The division into books, like all similar divisions (Cp. Sir G.C. Lewis in the Classical Museum, vol. ii. p 1.), is probably later than the age of Plato. The natural divisions are five in number;—(1) Book I and the first half of Book II down to the paragraph beginning, 'I had always admired the genius of Glaucon and Adeimantus,' which is introductory; the first book containing a refutation of the popular and sophistical notions of justice, and concluding, like some of the earlier Dialogues, without arriving at any definite result. To this is appended a restatement of the nature of justice according to common opinion, and an answer is demanded to the question—What is justice, stripped of appearances? The second division (2) includes the remainder of the second and the whole of the third and fourth books, which are mainly occupied with the construction of the first State and the first education. The third division (3) consists of the fifth, sixth, and seventh books, in which philosophy rather than justice is the subject of enquiry, and the second State is constructed on principles of communism and ruled by philosophers, and the contemplation of the idea of good takes the place of the social and political virtues. In the eighth and ninth books (4) the perversions of States and of the individuals who correspond to them are reviewed in succession; and the nature of pleasure and the principle of tyranny are further analysed in the individual man. The tenth book (5) is the conclusion of the whole, in which the relations of philosophy to poetry are finally determined, and the happiness of the citizens in this life, which has now been assured, is crowned by the vision of another.
Or a more general division into two parts may be adopted; the first (Books I - IV) containing the description of a State framed generally in accordance with Hellenic notions of religion and morality, while in the second (Books V - X) the Hellenic State is transformed into an ideal kingdom of philosophy, of which all other governments are the perversions. These two points of view are really opposed, and the opposition is only veiled by the genius of Plato. The Republic, like the Phaedrus (see Introduction to Phaedrus), is an imperfect whole; the higher light of philosophy breaks through the regularity of the Hellenic temple, which at last fades away into the heavens. Whether this imperfection of structure arises from an enlargement of the plan; or from the imperfect reconcilement in the writer's own mind of the struggling elements of thought which are now first brought together by him; or, perhaps, from the composition of the work at different times—are questions, like the similar question about the Iliad and the Odyssey, which are worth asking, but which cannot have a distinct answer. In the age of Plato there was no regular mode of publication, and an author would have the less scruple in altering or adding to a work which was known only to a few of his friends. There is no absurdity in supposing that he may have laid his labours aside for a time, or turned from one work to another; and such interruptions would be more likely to occur in the case of a long than of a short writing. In all attempts to determine the chronological order of the Platonic writings on internal evidence, this uncertainty about any single Dialogue being composed at one time is a disturbing element, which must be admitted to affect longer works, such as the Republic and the Laws, more than shorter ones. But, on the other hand, the seeming discrepancies of the Republic may only arise out of the discordant elements which the philosopher has attempted to unite in a single whole, perhaps without being himself able to recognise the inconsistency which is obvious to us. For there is a judgment of after ages which few great writers have ever been able to anticipate for themselves. They do not perceive the want of connexion in their own writings, or the gaps in their systems which are visible enough to those who come after them. In the beginnings of literature and philosophy, amid the first efforts of thought and language, more inconsistencies occur than now, when the paths of speculation are well worn and the meaning of words precisely defined. For consistency, too, is the growth of time; and some of the greatest creations of the human mind have been wanting