Abstract
It is now generally recognized that Plato's whole theory of the Ideal State is based upon the principle that human society is ‘natural’ . As against the antisocial doctrines of certain sophists, this proposition means, in the first place, a denial of the view that society originated in a primitive contract. But Plato does not merely reject this false opinion; he also sets up an alternative doctrine that the state is natural, in the sense that a human society constructed on ideal lines1 would be one that should reflect the structure of man's soul, and give full play to the legitimate functions of every part of his nature. Accordingly, it is vital to his purpose in the Republic to show that the division of the Ideal State into three classes—Guardians, Auxiliaries, Producers—corresponds to the division of the soul into three ‘parts’ , ‘kinds’, or ‘forms’ —the Reflective, Spirited, and Appetitive