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A.J. Ayer (1910-1989)

Alistair MacFarlane considers the populariser of Logical Positivism.

Sir Alfred Ayer (Freddie to friends) achieved great success with his first book Language, Truth and Logic (1936). Written with verve and enthusiasm, it gave a clear statement of Logical Positivism. This doctrine maintained that there are only two ways in which one can make meaningful statements: first by making statements which can be verified by observation; second, by making ones which are true in virtue of the rules of language. Anything else is meaningless. In particular, the idea that philosophy is a search for first principles was “a superstition from which we are freed by the abandonment of metaphysics.”

According to Logical Positivism, metaphysics is nonsense. Then in June 1988 Ayer had what might unkindly be called a metaphysical experience. While in intensive care in University College Hospital his heart stopped beating, and he was clinically dead for four minutes. Astonishingly, he gave a detailed account o f his experience during that time in the London Sunday Telegraph for 28th August 1988 in an article luridly entitled by a sub-editor ‘What I Saw When I Was Dead’. In an attempt to retrieve the situation, he published an article in the Spectator of 15th October 1988 in which he said that he’d wished to call the first article ‘That Undiscovered Country’. But he had come a long way from the blithe certainties of Logical Positivism.

Alfred Jules Ayer was born in London on 29th October 1910, the only child of immigrants. His father came from Switzerland, and eventually became a partner in a firm of timber merchants. His mother, whose maiden name was Citroën, came from a family of jewellers in Amsterdam, a branch of which moved to France and founded the famous car firm. As the only son of well-connected parents, his family were determined to make him into an English gentleman, which as a first step meant sending him to a good preparatory school. And in the summer of 1923, his prep school sent him on a trip to Eton to keep their star scholarship candidate company. Taking the entrance exam himself purely to pass the time, he succeeded while the official candidate failed. Unwilling to go to what he felt would be a snobbish environment, he was persuaded by his paternal grandfather that “becoming an Etonian would be a source of future advantages” – and it evidently was good preparation for the Oxford scholarship examinations. Elected by Christ Church to the first of its open Classical scholarships in the winter of 1928-29, he became a pupil of Gilbert Ryle, a well-known philosopher. Ayer graduated in 1932 and was appointed to a research fellowship in Christ Church. Before taking up this post, he had a few months leave of absence, and discussed with Ryle how to make the best use of it. Ryle had met Moritz Schlick at a philosophical congress two years earlier. Despite only talking to him for half an hour, Ryle became convinced of the originality and importance of what Schlick and his colleagues were doing. So Ryle said, “something important is happening in Vienna. Go there and find out what it is.”

Modern philosophy has been said to have begun in 1903, when G.E. Moore and Bertrand Russell broke away from the Idealism which had dominated philosophy in the nineteenth century. The first fully-fledged school of twentieth century philosophy, which became known as the Vienna Circle, developed in Austria during the 1920s, and its new approach was called ‘Logical Positivism’. Schlick, its leader, was a German who had been trained in physics, and who sought to create a philosophy which had the clarity and certainty he had found there. Other prominent members of the Vienna Circle were Otto Neurath and Rudolf Carnap. Schlick warmly welcomed Ayer to the Circle, and Ayer stayed in Vienna from November 1932 until the spring of 1933. Although only twenty-two, he found himself working closely with some of the most famous names in modern philosophy.

Ayer returned to Oxford full of excitement for the ideas of Logical Positivism. Isaiah Berlin, with whom he regularly discussed philosophy, was impressed by his enthusiasm and asked him, “Why don’t you write a book about it?” So in eighteen months he wrote Language, Truth and Logic, published when he was just twenty-five. The older philosophers in Oxford were outraged by its brutal demolition of the claims of metaphysics, and so Ayer found it difficult to get a permanent position there. He remained a research fellow there until the outbreak of war. Enlisting in the Welsh Guards, in 1941 he was seconded to Military Intelligence, spending time in London, New York and Algiers. After the allied invasion of Europe he spent most of 1945 in the British Embassy in Paris, and was demobbed with the rank of Captain. Although unable to pursue philosophical work during the war, he was elected in his absence to a Fellowship and Tutorship at Wadham College, Oxford, where he returned after leaving military service. Soon afterwards he became the Grote Professor of the Philosophy of Mind and Logic at University College, London. In 1946 a second edition of Language, Truth and Logic was published and became a huge success. Having established a very successful department of philosophy in London, he returned to Oxford as Wykeham Professor of Logic in 1959. In the early summer of 1989, he was admitted to hospital with a collapsed lung, and died on the 27th June.

In the second edition of Language, Truth and Logic, Ayer conceded that “the questions [of knowledge] with which the book deals are not in all respects so simple as it makes them appear.” He spent most of his subsequent career investigating them in more depth. The confidence so characteristic of the early book was replaced by a painstaking investigation of issues which he felt he had disposed of too quickly. These lengthy studies established his reputation as a first-rate philosopher. The Problem of Knowledge (1956) is considered his best book.

Ayer was widely known beyond the narrow field of professional philosophy. He did not deny he was a vain man – said to be part of his attraction to a wide circle of famous friends – but he carefully distinguished it from egotism. An egotist, he said, thought he should have more medals, whilst a vain man just enjoyed those he had. Among his own ‘medals’ were a knighthood, Fellow of the British Academy, and Chevalier of the Legion d’Honneur. But after the huge success of Language, Truth and Logic, it was never glad, confident morning again.

© Sir Alistair Macfarlane 2011

Sir Alistair MacFarlane is a former Vice-President of the Royal Society and a retired university Vice-Chancellor.

Language, Truth and Logic

In Language, Truth and Logic A.J. Ayer put forward the verification principle, the idea that in order to be meaningful, statements must be tautological (true by definition, or because of the meaning of the words involved) or empirically verifiable (scientific). To the first category belong mathematical and logical statements whose truth can be known a priori (i.e., without looking at the world), whilst to the latter belong statements about the observable world around us. For Ayer, a meaningful statement must be one of these two types of propositions, and is either true or false. According to Ayer, tautologies are ‘analytic’, and (unlike, say, Kant) for Ayer, analytic statements, such as Pythagoras’ Theorem, can present new knowledge, since they reveal latent truths in the information we already have. However, they cannot give us knowledge regarding ‘matters of fact’, such as ‘birds can fly’. Matters of fact are not true by necessity, and are only reached via ‘synthetic’ statements, which involve information we didn’t already have.

Ayer differentiates between ‘strong verification’ and ‘weak verification’, which indicates how rigorously a proposition (idea) can be confirmed. ‘Strong verification’ refers to propositions which are true by their very definition, whilst ‘weak verification’ refers to the gradual corroboration of empirically testable statements.

The (logical?) conclusion of the verification principle, adopted by the Logical Positivists, is that metaphysical and religious statements are meaningless, since they cannot be expressed either in an empirically verifiable or a tautological form. Arguably however, by presenting rules for the limits of knowledge, Ayer’s criteria present a metaphysical theory – which is of course forbidden by that very theory.

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