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.