Plato was one of the ﬁrst social scientists and undoubtedly by far the most inﬂuential. In the sense in which the term ‘sociology’ was understood by Comte, Mill, and Spencer, he was a sociologist; that is to say, he successfully applied his idealist method to an analysis of the social life of man, and of the laws of its development as well as the laws and conditions of its stability. In spite of Plato’s great inﬂuence, this side of his teaching has been little noticed. This seems to be due to two factors. First of all, much of Plato’s sociology is presented by him in such close connection with his ethical and political demands that the descriptive elements have been largely overlooked. Secondly, many of his thoughts were taken so much for granted that they were simply absorbed unconsciously and therefore uncritically. It is mainly in this way that his sociological theories became so inﬂuential.