In my earlier investigations of the ‘longer road’ in Books IV and VI–VII of the Republic (pp. 19–44 above), I come to the conclusion that the good which the Form of the Good is the Form of is benefit or advantage pure and simple. It is not some moral good, or some ‘intrinsic good’ (whether utilitarian or quite impersonal), or some mystical good. This, in spite of the fact that moral, ‘intrinsic’, utilitarian, impersonal or mystical goods are nowadays almost universally supposed to exhaust the possibilities as to what the Form of the Good is all about. The Form of the Good is, quite simply, the Form of Advantage.

This identity, I also noted, suggests two important possibilities. First, suppose we could show that the greater advantage of the just human being is that human being's greater happiness. Then we might be able to show that the announced main question of the Republic – ‘Is the just individual happier than the successfully unjust individual?’ – actually is the main question of the Republic. To show this would be to reject two other entirely natural candidates for being the main question or questions – one concerning utopian political philosophy, and one concerning the metaphysics of the Forms. A second possibility is this: we might be able to bring the ethical theory of the Republic into rather closer relation to the ethics of the Socratic dialogues than would usually be allowed.