According to Plato’s Republic, the human soul has three different elements, one consisting of raw appetites, another consisting of drives (such as anger and ambition), and a third consisting of thought or intellectual idea. In the virtuous or a “just” person, each of these elements fulfill a unique function and does so under the governance of reason. Likewise, according to Plato, in the ideal or “just” state there are also three elements, each of which fulfill its unique function and does so in accordance with the dictates of reason.
The lowest element in the soul-the appetitive element-corresponds in the well-ordered state to the class of a craftsman. The souls drive element corresponds in the state to the class of police-soldiers, who are auxiliaries to the governing class. This last class, in the well ordered state, corresponds to the intellectual, rational element of the soul.
The governing class, according to Plato, compromises a select few highly educated and profoundly rational individuals, including women so qualified. An individual becomes the member of a class by birth, but he or she has to move to a higher or lower class according to aptitude.
In a healthy state, said Plato, as in a well ordered soul, the rational element is in control. Thus, for Plato, the ideal state is a class structured aristocracy ruled by “Philosopher Kings”.
Unlike the craftsmen, the ruling elite and their auxiliaries, who jointly are the guardians of society, should have neither private property nor even private families: property, wives, and children are all possessions held in common. Reproduction among the guardians is to be arranged in such a way as to improve the blood line of their posterity in terms of intelligence, courage and other qualities apt for leadership. The guardians not only must be trained appropriately for soldering but also must be given a rigorous intellectual that, for the few whose unique abilities allow it, prepares them for advance work in mathematics and dialectic (that is the Socratic Method). These few at the age of fifty and after many years of public service, advance to membership in the ruling aristocracy and to leadership of the state. Such is Plato’s vision of political structure.