In this survey, John Passmore concentrates on the British tradition in logic, metaphysics and the theory of knowledge, yet he never neglects parallel developments in Europe and America. He considers the crucial new insights that were generated into probability, propositions and private languages, meaning, minds and bodies and the limits of science. Accounts explore the main schools and individual contributions of philosophers ranging from Ayer to Bradley, from Heidegger to Popper, from Moore to Merleau-Ponty and from Russell to Ryle.