As a species of egoism, Hedonism holds that our only ultimate pleasure is the self-directed desire for pleasure and the avoidance of pain. Bishop Butler is widely regarded as having refuted hedonism. I argue that Butler's argument failed to undermine Hedonism, because his premises concern what people want, while Hedonism concerns why people have the wants they do. Even if the desires for external things were a prerequisite for obtaining pleasure, nothing would follow about why people desire external things.

Just as there are rational requirements on thought, there are rational requirements on action. This book defends a conception of ethics, and a related conception of human nature, according to which altruism is included among the basic rational requirements on desire and action. Altruism itself depends on the recognition of the reality of other persons, and on the equivalent capacity to regard oneself as merely one individual among many.