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.) 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.