A. J. Ayer

A. J. Ayer, full name Alfred Jules Ayer (1910-89), British philosopher, who influenced the development of contemporary analytic philosophy. He taught at the universities of Oxford and London and became Wykeham Professor of Logic at Oxford in 1959.

Ayer's book Language, Truth, and Logic (1936) was an influential expression of logical positivism. Although his views were later modified, he early maintained that all meaningful statements are either logical or empirical. According to his principle of verification, a statement is considered empirical only if some sensory observation is relevant to determining its truth or falseness. Sentences that are neither logical nor empirical—including traditional religious, metaphysical, and ethical sentences—are judged nonsensical. Other works of Ayer include The Problem of Knowledge (1956), the Gifford Lectures of 1972-73 published as The Central Questions of Philosophy (1973), and Part of My Life: The Memoirs of a Philosopher (1977).