This, the 21st volume in the Library of Living Philosophers, is more than Sir Alfred Ayer's final word on the philosophical issues that preoccupied him for more than sixty years; the list of contributors is a roll-call of some of the greatest living figures in philosophy, each expertly addressing a key problem arising in Ayer's work. Most of the critical papers are answered directly and in detail by Sir Alfred-he completed his replies to 21 of the 24 papers before his death. Contributors include: A. J. Ayer, Evandro Agazzi, James Campbell, David S. Clarke, Michael Dummett, Elizabeth Eames, John Foster, Dimitri Ginev, Paul Gochet, Martin Hollis, Ted Honderich, Tscha Hung, Peter Kivy, Arne Naess, D. J. O'Connor, Desiree Park, David Pears, Azarya Polikarov, Hilary Putnam, Francisco Miró, Quesada C., A. Anthony Quinton, Emanuele Riverso, Ernest Sosa, T. L. S. Sprigge, Barry Stroud, and David Wiggins.