This is a defense of John Stuart Mill’s proof of the principle of utility in the fourth chapter of his Utilitarianism. The proof is notorious as a fallacious attempt by a prominent philosopher, who ought not to have made the elementary mistakes he is supposed to have made. This book shows that he did not. The aim is not to glorify utilitarianism, in a full sweep, as the best normative ethical theory, or even to vindicate, on a more specific level, (...) Mill’s universalistic ethical hedonism as the best form of utilitarianism. The book is concerned only with Mill’s utilitarianism, and primarily with his proof of the principle of utility. The purpose is to show that Mill proceeds intelligibly and systematically in pursuing a well-defined project in the fourth chapter of Utilitarianism, and that he successfully defends what he sets out to establish in his proof of the principle of utility. (shrink)