Evidently, these two questions cannot stand together. In answering the second, Sokrates presupposes a certain determination of the first; inconsistent with that unqualified ignorance, of which he had just made profession. Sokrates now professes to know, not merely that Justice is a good, but to what class of good things it belongs. The first question has thus been tacitly dropped without express solution, and has given place to the second. Yet Sokrates, in providing his answer to the second, includes implicitly an answer to the first, so far as to assume that Justice is a good thing, and proceeds to show in what way it is good.
Some say that Justice is good (i.e. that it ensures, or at least contributes to, the happiness of the agent), but not per se: only in its ulterior consequences. Taken per se, it imposes privation, loss, self-denial; diminishing instead of augmenting the agent’s happiness. But taken along with its results, this preliminary advance is more than adequately repaid; since without it the agent would not obtain from others that reciprocity of justice, forbearance, and good treatment without which his life would be intolerable.
If this last opinion be granted, Glaukon argues that Justice would indeed be good for weak and middling agents, but not for men of power and energy, who had a good chance of extorting the benefit without paying the antecedent price. And Thrasymachus, carrying this view still farther, assumes that there are in every society men of power who despotise over the rest; and maintains that Justice consists, for the society generally, in obeying the orders of these despots. It is all gain to the strong, all loss to the weak. These latter profit by it in no other way than by saving themselves from farther punishment or ill usage on the part of the strong.
Position to be proved by Sokrates — Justice makes the just man happy per se, whatever be its results.
Sokrates undertakes to maintain the opposite — That Justice is a good per se, ensuring the happiness of the agent by its direct and intrinsic effects on the mind: whatever its ulterior consequences may be. He maintains indeed that these ulterior consequences are also good: but that they do not constitute the paramount benefit, or the main recommendation of Justice: that the good of Justice per se is much greater. In this point of view, Justice is not less valuable and necessary to the strong than to the weak. He proceeds to show, what Justice is, and how it is beneficial per se to the agent, apart from consequences: also, what Injustice is, and how it is injurious to the agent per se, apart from consequences.[43]
[43] Plato, Republic, ii. pp. 368 seq.
Argument of Sokrates to show what Justice is — Assumed analogy between the city and the individual.
He begins by affirming the analogy between an entire city or community, and each individual man or agent. There is justice (he says) in the entire city — and justice in each individual man. In the city, the characteristics of Justice are stamped in larger letters or magnified, so as to be more easily legible. We will therefore first read them in the city, and then apply the lesson to explain what appears in smaller type in the individual man.[44] We will trace the steps by which a city is generated, in order that we may see how justice and injustice spring up in it.
[44] Plato, Republic, ii. pp. 368-369.
It is in this way that Plato first conducts us to the formation of a political community. A parallel is assumed between the entire city and each individual man: the city is a man on a great scale — the man is a city on a small scale. Justice belongs both to one and to the other. The city is described and analysed, not merely as a problem for its own sake, but in order that the relation between its constituent parts may throw light on the analogous constituent parts, which are assumed to exist in each individual man.[45]