John Rist surveys the history of ethics from Plato to the present and offers a vigorous defence of an ethical theory based on a revised version of Platonic realism. In a wide-ranging discussion he examines well-known alternatives to Platonism, in particular—Epicurus, Hobbes, Hume and Kant, as well as contemporary "practical reasoners". His accessible study is enhanced by a strong sense of philosophical history, and will be of interest to students and scholars of ethics.