AJ Ayer’s Language, Truth, & Logic

1,952 words

The principle of verification is supposed to furnish a criterion by which it can be determined whether or not a sentence is literally meaningful. A simple way to formulate it would be to say that a sentence had literal meaning if and only if the proposition it expressed was either analytic or empirically verifiable.
-A. J. Ayer, Language, Truth and Logic

When I use a word it means just what I choose it to mean – neither more nor less.
-Humpty-Dumpty, from Lewis Carroll’s Through the Looking-Glass

Alfred Jules Ayer was an English philosopher usually associated with the school of thought known as Logical Positivism. His first book, Language, Truth and Logic (LTL), was published in 1936 when Ayer was 26 years old, and although he later thought it suffered from being a young man’s book, it had a powerful effect on British philosophy. It is a short volume, extremely clearly written, and remains an excellent introduction to language-based philosophy.

The central tenet of LTL is that there are only two types of sentence or proposition which can have meaning. These are empiric or synthetic, and analytic. The former requires verification from experience, the latter does not, being indicative only of the relationship between the symbols or words used, and not requiring reference to the outside world to be verified: “The criterion which we use to test the genuineness of apparent statements of fact is the criterion of verifiability.”

LTL thus relies on Kantian categories, and Ayer discusses the German in some detail. In particular, Ayer stresses the importance of Kant’s view that existence is not an attribute of any existing thing, but a prerequisite for any attributes to exist at all .

The book is punctuated with examples that illustrate Ayer’s overall thesis. Thus:

The proposition “There are ants which have established a system of slavery” is a synthetic proposition. For we cannot tell whether it is true or false merely by considering the definitions of the symbols which constitute it. We have to resort to actual observation of the behaviour of ants. On the other hand, the proposition “Either some ants are parasitic or none are” is an analytic proposition. For one need not resort to observation to discover that there either are or are not ants which are parasitic.

Ayer names his primary influences as Wittgenstein and Bertrand Russell, themselves an extension of aspects of the work of the great British empiricists Locke, Berkeley, and Hume. LTL is also a good and simple (albeit brief) introduction to these philosophers.

Ayer’s debut is also indicative of the British unease with the formative period of Continental European philosophy, and it is significant that LTL’s first chapter is a rejection of metaphysics. This branch of philosophy never sat easily with the British, and was nicely ridiculed by Lord Byron in 1819’s Don Juan, when he satirized fellow-poet Coleridge as “Explaining metaphysics to the nation. I wish he would explain his explanation”.

I was delighted to see, incidentally, that Byron’s magnificent ottava rima poem was one of the boyhood favorites of Argentinian President Javier Milei.

But Ayer’s critique of the metaphysicians is less poetic. “Our object”, he writes, “is merely to show that philosophy, as a genuine branch of knowledge, must be distinguished from metaphysics.”

This is not simply the marking out of philosophical boundaries. Ayer has grounds for his rejection:

One way of attacking a metaphysician who claimed to have knowledge of a reality which transcended the phenomenal world would be to enquire from what premises his propositions were deduced. Must he not begin, as other men do, with the evidence of his senses? And if so, what valid process of reasoning can possibly lead him to the conception of a transcendent reality?

That Ayer is aiming squarely at the post-Kantian Continent is affirmed by the fact that the only philosopher named in LTL who is not in the classic empirical tradition is Martin Heidegger:

In general, the postulation of real non-existent entities results from the superstition… that, to every word or phrase that can be the grammatical subject of a sentence, there must somewhere be a real entity corresponding. For as there is no place in the empirical world for many of these “entities”, a special non-empirical world is invoked to house them. To this error must be attributed, not only the utterances of a Heidegger, who bases his metaphysics on the assumption that “Nothing” is a name which is used to denote something peculiarly mysterious.

Heidegger’s treatment of “Nothingness” is a vast topic, and one subsequently thematized by Sartre in Being and Nothingness, but Ayer’s ascription of grammar as the source of philosophical misdirection has a curious and Venn-like overlap with Nietzsche, who writes often of grammatical error as the source of erroneous philosophical beliefs. This is remarkably similar to Ayer’s position in LTL.

So, having dismissed metaphysics, Ayer must now explain what remains to the province of the philosopher, and this is one of the cornerstones of LTL, which defines philosophy privatively, not so much by what it is as by what it is not: “The philosopher, as an analyst, is not directly concerned with the physical properties of things. He is concerned only with the way in which we speak about them.”

Ayer’s thesis is that while philosophers often behave as though they are examining and explaining a “real world”, what they are in fact doing – and should be doing, albeit knowingly – is analyzing the way in which we talk about any such world. Thus, in the third chapter, which concerns the methodology of philosophy, the very notion of philosophical questioning undergoes an important shift:

The question, ‘What is the nature of a material thing?’ is, like any other question of that form, a linguistic question, being a demand for a definition. And the propositions which are set forth in answer to it are linguistic propositions, even though they may be expressed in such a way that they seem to be factual. They are propositions about the relationship of symbols, and not about the properties of the things which the symbols denote.

This looks as though all philosophy is left with after an epistemological clear-out is the dry analysis of logical convention and the relation between symbols, and that it is not equipped to provide knowledge in any real sense. Not so, says Ayer: “There is a sense in which analytic propositions do give us new knowledge. They call attention to linguistic usages, of which we might otherwise not be conscious.”

Again, there is a link, however apparently tenuous, between Ayer’s philosophy in LTL and the Continental metaphysics he rejects. Nietzsche, and even Derrida, note that language is a part of the real world, not merely some encyclopedic recording device of that world, and thus requires the same analysis as any concerning facts about reality in terms of its composition outside of analytic statements, propositions concerning things “out there” in the world. But no philosophy exists in isolation from its history.

Of course, there are limits to logic. It is hermetically sealed, apparently functioning within its own limits and having no need of any real world in which to operate. The French mathematician Poincaré, Ayer notes, believed that a danger for mathematics was that it was ultimately an immense tautology, 2 + 2 = 4 writ large. But the influence of Wittgenstein is always present in LTL, and the world and its relations have themselves an intimate relationship with language that is essential for any philosophy at all to take place.

A determinate factor in describing reality is not, or not only, truth – usually the Grail of the philosopher – but falsehood and its function in either the analytic or the empirical:

To say that a geometrical proposition, or a system of geometrical propositions, is false is to say that it is self-contradictory. But an empirical proposition, or a system of empirical propositions, may be free from contradiction, and still be false. It is said to be false, not because it is formally defective, but because it fails to satisfy some material criterion. And it is our business to discover what this criterion is.

And this function carries over to the non-geometrical. Thus, although it is self-contradictory to say that the author of Hamlet did not write Hamlet, it is not so to say that the author of Hamlet did not write Macbeth, although it is false.

Ayer does not shy away from the big philosophical questions, no matter how restrained and limited his analytical and verificationist approach may appear. His treatment of religion is both cursory and thoroughly in line with the main thesis of LTL:

We are often told that the nature of God is a mystery which transcends the human understanding. But to say that something transcends the human understanding is to say that it is unintelligible. And what is unintelligible cannot significantly be described.

Ayer was also associated with what came to be called “emotivism”, the belief that some apparently verifiable language is in fact merely an assertion of personal belief, as with ethical statements:

Our contention is simply that, in our language, sentences which contain normative ethical symbols are not equivalent to sentences which express psychological propositions, or indeed empirical propositions of any kind.

There is an excellent science-fiction novel lurking in Ayer’s imagining a being who would have no need for the analytic: “A being whose intellect was infinitely powerful would take no interest in logic and mathematics. For he would be able to see at a glance everything that his definitions implied.”

The existence of other minds, the external world, ethics and morals, and the nature and relevance of probability are all addressed in the second half of LTL. Ayer rather casually dismisses the age-old mind/body problem, which he does not consider to be such, again using the filtration system of verification.

In the final chapter of LTL, Ayer examines three great oppositions within philosophy hitherto: Rationalism and empiricism, realism and idealism, and monism and pluralism. For those new to philosophy, this section makes of LTL an excellent introduction to philosophy’s internal tensions, and lays out clearly the grounding concepts and belief systems of proponents of these various allegiances. I would recommend LTL to anyone looking for a “way in” to philosophy.

I first read this book over 40 years ago, when I was first coming to grips with philosophy, which went on to become the great love of my life. Despite becoming enchanted with existentialism and post-structuralism as my reading progressed – and philosophy is almost all reading – I never forgot about it. Some sentences in LTL this time around came back to me like memories of a dream. Speaking of which, I have a rather tenuous but very strange connection with A. J. Ayer.

In July of 1989 I was coming round after an operation in Queen Mary’s University Hospital, London. It is customary to have a nurse in attendance when a patient recovers consciousness, and I believed at first that I was dreaming, as the name-badge of my nurse read “Penny Lane”. As I came to realize I was not in some Beatles-themed dream and became able to converse, Penny asked me what I did. I told her my job, and that I was also completing a PhD in philosophy. She became interested and said that a famous philosopher had been in the very bed in which I lay, and had indeed passed away there recently. I asked her who it was, and she replied, “Freddie. Freddie Ayer. He was a lovely man.”

I can’t verify this story, either analytically or empirically, but it was an odd sensation. I don’t believe any transmigration of souls took place. That would have been too metaphysical for one of England’s finest 20th-century philosophers.