INTRODUCTION: WHY SO SO MUCH POLITICS? DEFENSE OF JUSTICE

In the Republic, Socrates argues that justice ought to be valued both for its own sake and for the sake of its consequences (358a1–3). His interlocutors Glaucon and Adeimantus have reported a number of arguments to the effect that thes value of justice lies purely in the rewards and reputation that are the usual consequence of being seen to be just, and have asked Socrates to say what justice is and to show that justice is always intrinsically better than is acting contrary to justice when doing so would win you more non-moral goods. Glaucon presents these arguments as renewing Thrasymachus' Book 1 position that justice is “another's good” (358b–c, cf. 343c), which Thrasymachus had associated with the claim that the rulers in any constitution frame laws to their own advantage and call these laws' prescriptions “justice” (338d–339e); Glaucon picks up this claim in his account of the founding of the terms of justice by social contract (359a–b). In reply, on the assumption that the justice in the soul is the same sort of thing as the (more abundant or at any rate more visible) justice in the city (368e–369a), a claim he will later justify in the Book 4 argument for the tripartition of the soul, Socrates first describes a city based on need and specialization (369b–372d), then introduces and elaborates the musical and physical education of the citizens (376c–402a, 403c–412b), and then identifies the four virtues, which he assumes he will find in such a city (427e).