This is part of a three-volume collection of most of David Lewis's papers in philosophy, except for those which previously appeared in his Philosophical Papers (Oxford University Press, 1983 and 1986). This third volume is devoted to Lewis's work in ethics and social philosophy.. "The purpose of this collection, and the two preceding volumes, is to disseminate more widely the work of an eminent and influential contemporary philosopher. The volume will serve as a useful work of reference for teachers and students of philosophy.