Philosophy’s critics have a variety of criteria from which to choose. The first question to ask about any philosopher’s claims is whether they are true. But there are other questions which sometimes crowd this one out. Is his work accessible and persuasive? Does it touch our lives? Will it last? With so many options there is no pretending that it is obvious what counts as success. Certainly we can’t always hope to have everything now that the subject has acquired a complexity which makes it almost impossible to combine accuracy and accessibility. The technicalities of philosophy may not be as great as those of science, but they are enough to put much of what is written beyond the reach of most people. Even etnics, which touches our lives more closely than any other branch of philosophy, is now developing formidable intricacies, and in theory of knowledge, logic and metaphysics the questions themselves often need specialists to formulate them. So we look back with envy at earlier ages when the fruit that few could pick was shared and digested by many.
However, it does still occasionally happen that a philosopher writes a book without any practical implications and yet with a wide appeal both inside and outside the profession. It is still possible to present a piece of purely theoretical philosophy in a way that connects it with the interests, or, at least, fires the imaginations, of people who have had no special training in the subject. A.J. Ayer’s first book, Language, Truth and Logic, published in 1936, achieved this effect, perhaps surprisingly, given that its main thesis was that much of what we say inside and outside philosophy is strictly meaningless. But there is pleasure in self-denial, especially when it involves sweeping away the results of other people’s self-indulgence. Anyway, the book is written with such spirit and dash, that, though it is an attempt to limit our minds, it is paradoxically liberating, like any cavalry charge, whatever its purpose.
But is it true that so much of what we say is strictly meaningless? If metaphysics and theology are relinquished, can we really see our ascriptions of moral or aesthetic value going the same way? They do at least seem to be more directly based on our experience. But Ayer’s test of meaning was a coarse-meshed sieve, which only retained statements with plain sensory content and let all the rest go, including our moral and aesthetic reactions. According to him, they were no more than expressions of feeling. Statements about the past, about other people’s minds, and even about the physical world at the present moment, were in temporary jeopardy, because it was not obvious how the mesh could retain them. Science seemed to be trying to eliminate its rivals by a method which would force it to eliminate itself.
The radical empiricism of Ayer’s first book places it in a well-marked tradition in British philosophy. Hume’s Treatise of Human Nature, another young man’s book, is its greatest precursor, and the theme was carried on by Mill and Russell. In Russell’s work it was associated with a theory of meaning, and Ayer’s contribution was to weave into this pattern the philosophy of language which the Vienna Circle had extracted from Wittgenstein’s Tractatus. The result was a linguistic minimalism, which more or less matched the psychological minimalism of Hume, and which, like it, precariously occupied the margin of the picture of the world from which it had started. Science inspired this philosophy, but the reaction against unscientific speculation was so extreme that it put science itself in jeopardy and even left its own status unsecured.
If this extreme form of empiricism cannot be accepted as true, perhaps it fares better when it is judged by some other criterion. It may be the inadequate expression of a valuable insight, and as such it may produce lasting effects even though the verdict goes against it on the question of truth. It is not uncommon for philosophical theories to possess this kind of pragmatic value. Ayer’s early minimalism, as John Foster shows, was the point of departure for much of his later, authoritative work in philosophy: it has largely determined his choice of subjects in the history of ideas – Moore, Russell, the Vienna Circle, the Pragmatists, Wittgenstein and now the evidently congenial Voltaire; and it has just inspired a collection of articles dealing with its problems and marking the 50th anniversary of the publication of Language, Truth and Logic.
Nobody doubts the need to make philosophy widely accessible. It starts as an examination of ordinary experience and thought, and its results should not be kept esoteric. What is not so obvious is that philosophers can themselves learn a lot from clear and uncompromising theories which they do not accept. For they do not always command a clear view of where they stand, and they can often fix their own positions more accurately by relating them to something more extreme. This has been one of the functions of Ayer’s early version of empiricism: it shows how the curve of the graph develops beyond the point where it can be used.
Ayer has come to see his own early work in this light. He was right, he thinks, to let much that passes as meaningful fall through the mesh of his sieve, but wrong to retain so little. A purely phenomenal language could not capture what he wanted, which was the world as it is described in ordinary life and in science. So, like Russell and Wittgenstein before him, but not for the same reasons, he moved to a less extreme position.
That is one way of becoming a moderate empiricist, but a philosopher who takes up this position today is unlikely to have arrived by that route. However, he can still learn a lot from the possibility of such an approach, even if he knows that he could never actually find himself at its starting-point. It fixes his position on a larger map. Wittgenstein exploited extreme philosophical theories in this way in his later work. There is nothing quite like it in science. A scientific theory does not occupy the intersection of different co-ordinates, each with more extreme values, or, if it does, that is not the way to arrive at an understanding of it. This is why a philosopher’s interest in the history of philosophy is so close to his interest in the subject itself whereas a scientist’s interest in the history of science is separate.
Only a pragmatist would be happy to have his first philosophical work recommended on pragmatic grounds. But there is another criterion which Ayer would be more likely to accept: quality of argument. That is a scale on which all his work, early and late, comes as high as anyone’s. His thought is agile and strong and it is always expressed with perfect economy and lucidity. Philip Toynbee once compared him to the master of a gymnasium, lithe, elegant and ready to take on all comers: one by one, the great problems of philosophy advanced on him like Sumo wrestlers, only to be laid flat by a flick of the wrist. That fits Language, Truth and Logic exactly, but not his later work, in which the quick disposal of problems is no longer his aim. The same skill is now used to make the dialectical situation perfectly clear in all its details. If a conclusion is reached, you can see exactly how it was done, and where it might be possible to diverge to a different destination.
It is this virtuosity that explains why his work has been so influential, and the actual positions adopted by him have probably counted for less. If philosophy were like science, this would not be a possible explanation. But it is not like science – perhaps even less like it than Ayer would allow – and so its pursuit of understanding need not always end with theories, and when it does, they may matter less than the details of the investigation. The usual sharp distinction between practice and product seems not to be valid here.