Sidgwick maintains, plausibly, that the concept of a person's good is a normative one and takes for granted that it is normative for the agent's own choice and action. I argue that the normativity of a person's good must be understood in relation to concern for someone for that person's own sake. A person's good, I suggest, is what one should want for that person in so far as one cares about him, or what one should want for him for (...) his sake. I examine Sidgwick's defence of the axioms of rational prudence and argue that it is powerless to convince anyone who lacks self-concern or thinks he has no reason to care for himself. To the extent that Sidgwick is persuasive, I argue, it is because he insinuates an assumption of self-concern. Similarly, Sidgwick's defence of the axiom of rational benevolence tacitly assumes, not just impersonality, but equal concern. (shrink)