This is the most authoritative and engaging philosophical reference work in English. It gives clear and reliable guidance to all areas of philosophy and to the ideas of all notable philosophers from antiquity to the present day. The scope of the volume is not limited to English-language philosophy: it surveys the foremost philosophy from all parts of the world. A distinguished international assembly of more than two hundred contributors provide almost 2,000 alphabetically arranged entries which are not only instructive but also entertaining: they combine learning, lucidity, elegance, and wit. There are more than fifty extended entries of 3,000 words on the main areas of philosophy and the great philosophers: these include essays by Alasdair MacIntyre on the history of moral philosophy, Paul Feyerabend on the history of the philosophy of science, Jaegwon Kim on problems of the philosophy of mind, Richard Swinburne on problems of the philosophy of religion, David Charles on Aristotle, Peter Singer on Hegel, Anthony Kenny on Frege, and Anthony Quinton on philosophy itself. Short entries deal with key concepts (for instance, personal identity, time) doctrines (utilitarianism, holism), problems (the mind-body problem, the meaning of life), schools of thought (Marxist philosophy, the Vienna Circle), and practical issues (abortion, vegetarianism). Individual thinkers past (Pythagoras, Confucius, Galileo, Goethe, Burke, Santayana, de Beauvoir, Radhakrishnan) and present (over 150 contemporary figures, such as Chomsky, Derrida, and Popper) are profiled, and eighty of them are depicted in black-and-white portraits. Interspersed throughout are short explanations of particular philosophical terms (qualia, supervenience, iff), puzzles (the Achilles paradox, the prisoner's dilemma), and curiosities (the philosopher's stone, slime). Every entry is accompanied by suggestions for further reading. A chronological chart of the history of philosophy is located at the end of the book, together with fourteen diagrams showing the structure of philosophy and the relations between its subjects and doctrines. This book will be an indispensable guide and a constant source of stimulation and enlightenment for anyone interested in abstract thought, the eternal questions, and the foundations of human understanding.