24 SEPTEMBER 1994, Page 27


Why all of us should observe the Eleventh Commandment of Karl Popper


philosophers have not been of much use to us in this century. Ideally, a philosopher ought to be a thinker of pure and penetra- tive intelligence, who uses it both to seek truth and acquire wisdom and to convey them to the rest of us in ways we can use in our life and work. By this definition we have been ill-served, or rather scarcely served at all.

Bertrand Russell wrote innumerable books and magazine articles aimed at the general public, but it is impossible to point to any salient message of his which has stood the test of time. Most of his asser- tions in fact are contradicted by other state- ments, following one of his abrupt changes of opinion. And he snootily held that his `serious' work, by which he meant his Prin- cipia Mathematica, had nothing to do with ordinary people. For 70 years he enter- tained us as one of the leading actors in the intellectual soap opera 'What's Cooking Among the Eggheads?' but as for convey- ing wisdom he might never have lived.

Jean-Paul Sartre was less snooty and gen- uinely tried to make a philosophy of life available to the young. But half a century after he launched Existentialism there is nothing to show for it except the stale aroma of hot air. And, later, he went out of his way to teach bad morality, notably in the use of violence: one of his many apt pupils in the Third World, Pol Pot, is still around killing people. The best that can be said for Russell and Sartre is that they scorned the academic parlour tricks which occupied most 20th- century philosophers. Both Wittgenstein and Freddy Ayer, the most famous of them, went a long way towards persuading me and countless other people that modern philosophy was a frivolous affair, a sort of rarefied quiz game which had no relevance to the great tragedies of our time. The mes- sage I got from Wittgenstein was that noth- ing could be proved at all. Ayer, in so far as he had any influence on most people, actu- ally did harm: as Lord Hailsham points out in his new book -- a remarkable effort for a man of 86, beautifully printed in his own handwriting -- Ayer persuaded many of his readers that most of the great moral and aesthetic truths on which civilisation depends are mere 'value judgments', inca- pable of philosophic validation, and there- fore meaningless. There was, however, one marvellous exception to this dismal showing by the professional philosophers of our time. Karl Popper, who died in London at the week- end, was not only a truly wise man but he contrived to spread enlightenment where it really matters: among men and women of affairs, the movers and shakers, people who actually exercise power or influence those who do. One would have to go back to Locke, or at any rate to Adam Smith, to find a philosopher who was more widely read and absorbed by politicians, senior civil servants, businessmen and scientists, writers and journalists. Popper was unable to prevent the monumental catastrophes of the 20th century but his teaching played a considerable part in bringing them to an end and will help to ensure they do not recur.

The messages he conveyed cover a wide area and mesh together with impressive strength. He was not a one-book man. His most famous work, The Open Society and Its Enemies (1945), was the most devastat- ing exposure of the crimes of totalitarian- ism ever written, which should have laid to rest for ever the absolutist strain which runs through philosophy from Plato on. But he followed this with his remarkable The Poverty of Historicism (1957), which exposes the folly of all gigantic attempts to explain the world, history, human behaviour etc., and to give it a determinist twist. All clever young men and women should be encour- aged to read these two books in their last year at school, or first at university, before they risk falling victim to the fashionable ism. Popper is an all-purpose vaccination course, a super-potent jab which, once administered, should protect the brilliant young from most intellectual diseases.

However, underlying these books, and in some ways even more important than them,

is his Logic of Scientific Discovery (1934), which embodies his whole approach to evi- dence and proof. Popper learned from Ein- stein, the hero of his youth, to be wary of the enthusiasm of discovery. When we are working on a problem, in science or any- thing else, we form a hypothesis and then endeavour to verify it empirically. Human nature being what it is, if the hypothesis is exciting in embodying a new and important truth, or if it accords with our preconceived ideas, we tend to look eagerly for evidence which supports it, and to ignore or brush aside evidence which doesn't fit. Worse still, if negative evidence thrusts itself on us, we brazenly modify the theory to accommodate it, instead of bravely admit- ting the hypothesis is false and starting all over again.

Popper cited Marx and Freud as out- standing examples of pseudo-scientists who fought to the death for their false hypothe- ses rather than admit the weight of evi- dence against them. By contrast, Einstein deliberately constructed his General Theo- ry of Relativity in such a way that it was easily falsified by empirical evidence and could not be considered valid until it passed the three vital tests he set it. Even so, it was no more than a provisional theo- ry, subject to constant verification. Popper taught us that all empirical knowledge is provisional, that the pride of certitude is the deadly sin, and that the endless quest for truth requires heroic intellectual courage.

These are lessons everyone can make use of and which apply to almost all higher forms of human activity, from the art of government and legislation to the writing of history. As a historian, I have taken Popper's methodology to heart though it requires terrific self-discipline. Once you have satisfied yourself that a certain inter- pretation of history is correct, nothing is harder than to force yourself systematically to grub around for evidence to refute it. But it must be done, to qualify for Popper's definition of a scientist.

The piece of paper I prize above all oth- ers is a letter he wrote me last year, approv- ing in the most generous terms of my book Modern Times. I have had it framed and it hangs in my study just above where I write to remind me daily that the principles of falsification and verification for which Pop- per stood are the Eleventh Commandment which all writers must observe at their peril.