From 1933 to 1940 he lectured on philosophy at Christ Church, Oxford.

Ayer was born in St John's Wood, in north west London, to a wealthy family from continental Europe.

In the Second World War he served as an officer in the Welsh Guards, chiefly in intelligence (Special Operations Executive (SOE) and MI6 After the war he briefly returned to Oxford University where he became a fellow and Dean of Wadham College.

He was also obsessed with sport: he had played rugby for Eton, and was a noted cricketer and a keen supporter of the Tottenham Hotspur football team.After graduation from Oxford University Ayer spent a year in Vienna, returned to England and published his first book, Language, Truth and Logic in 1936.The first exposition in English of Logical Positivism as newly developed by the Vienna Circle, this made Ayer at age 26 the 'enfant terrible' of British philosophy.Ayer was educated at Ascham St Vincent's School, a former boarding preparatory school for boys in the seaside town of Eastbourne in Sussex, in which he started boarding at the comparatively early age of seven for reasons to do with the First World War, and Eton College, a boarding school in Eton (near Windsor) in Berkshire.It was at Eton that Ayer first became known for his characteristic bravado and precocity.