A.J. Ayer burst like a supernova upon the Anglo-American philosophical world in 1936, with "Language, Truth and Logic", an eloquent, uncompromising manifesto for logical positivism which transformed the thinking of a generation. Inside a few years, philosophers were retreating from the position set forth in "Language Truth and Logic" with Ayer himself leading the retreat. The ensuing vogue for "ordinary language" philosophy was not admired by Ayer who became one of its most telling critics. In his subsequent writings he displayed a rare capacity for self-criticism, manifested in a readiness to admit that his earlier arguments had been inadequate. He modified his position on many issues, but remained to the end what he had been all along - an empiricist in the demanding tradition of Hume and Russell. Ayers's grace and clarity of style, his lack of pretentiousness, his logical rigour and his gift for penetrating to the heart of a problem are all exemplified in a succession of works, including "Thinking and Meaning" (1947), "The Problem of Knowlegde" (1956), "Probability and Evidence" (1973) and "Freedom and Morality" (1985).
This, the 21st volume in the "Library of Living Philosophy", is more than Sir Alfred Ayer's final word on the philosophical issues which preoccupied him for 60 years. The list of contributors is a roll-call of some of the greatest living figures in philosophy, each addressing a key problem arising from Ayer's work. Most of the critical papers are answered directly and in detail by Sir Alfred - he completed his replies to 20 of the 24 papers before his death.