Justice is a function not of actions or behavior as such--and by implication not of material experience more generally--but rather of the just conceptualization, which must precede the just action if the action and the one who performs it are to be considered authentically just, either by oneself or by others:
[Justice] . . . is not a matter of external behaviour, but of the inward self . . . . The just man . . . sets his house in order, by self-mastery and discipline . . . . Only when he has linked these parts together in well-tempered harmony . . . will he be ready to go about whatever he may have to do, whether it be making money . . . or the affairs of state (Plato 141-2).
The mechanism of harmony in personal and civic relationships is political education and desire for wisdom, a "constant passion for any knowledge that will reveal to them something of that reality which endures for ever and is not always passing into and out of existence" (Plato 190-1). These traits are identified with the philosopher-king, whose commitment to virtue, justice, and wisdom is the basis for the community's depositing sovereignty with the ruler.
Implicit in the entitlement to sovereignty held by the "Guardian of a commonwealth and its laws" is that he must be groomed in governance and virtue with a view toward attaining the highest kind and object of knowledge, which is "the essential nature of the Good, from which everything that is good and right derives its value for us" (Plato 214-215). Accordingly, virtue must be taught, or at any rate it must be learned, by means of serious study of a variety of arts, physical exercise, and sciences: "If a sound education has made [the rulers] reasonable men, they will easily see their way through all these matters a well as others" (Plato 114).
The republic conceived by Plato is evidence of moral structures that make society coherent and give people access to the Good. To be sure, in practice, the ...