THREE:It will be remembered that in an earlier section of this chapter we accompanied Plato to a period when he had provisionally adopted a theory in which the Protagorean contention that virtue can be taught was confirmed and explained by the Socratic contention that virtue is knowledge; while this knowledge again was interpreted in the sense of a hedonistic calculus, a prevision and comparison of the pleasures and pains consequent on our actions. We have now to trace the lines of thought by which he was guided to a different conception of ethical science."What did Mr. Balmayne tell you?" Hetty asked in reply.