Putting Philosophy to Work: Karl Popper's Influence on Scientific Practice

‘I think Popper is incomparably the greatest philosopher of science that has ever been’, writes Sir Peter Medawar, winner of the Nobel Prize for medicine and himself an experienced analyst of scientific thought and scientific practice. Medawar’s judgement has been echoed by many other eminent scientists. Sir Hermann Bondi states that: ‘There is no more to science than its method, and there is no more to its method than Popper has said’. Similarly Sir John Eccles, another Nobel Prizewinner, testifies to the impact of Popper’s writings on his approach to research: ‘my scientific life owes so much to my conversion in 1945.. . to Popper’s teachings on the conduct ofinvestigations . . . I have endeavoured to follow Popper in the formulation and in the investigation of fundamental problems in neurobiology’. In the book from which these quotations are taken,’ Magee emphasizes that Popper’s philosophy is a philosophy of action. It is intended to influence people’s practical acts and choices, .in science as well as in politics. Popper himself, in his 1958 Preface to The LogicofScientific Discoveely, stresses that his attempts to resolve certain problems in the philosophy of science are to be regarded as successful insofar as they contribute not only to philosophical knowledge but also to science.* Popper, then, seeks to have an impact on scientific practice and several aspects of his philosophy of science clearly reveal this concern with practical intervention. In Popper’s own words: ‘I shall try to establish the rules, or if you will the norms, by which the scientist is guided when he is engaged in research or in discovery, in rhe sense liere ~mders tood’ .~ That last qualifying phrase is all-important, if one is not to misunderstand Popper’s intention. Without it, Popper’s statement would read likea preface toa sociological description of the cognitive and technical norms which scientists actually employ. But Popper says clearly that this is not his goal. He defines ‘scientific knowledge’, and by implication ‘genuine scientist’ and ‘truly scientific action’, onthe basis ofapurelylogical analysis ofwhat isentailed in proofand disproof. His argument is that, in the realm of empirical knowledge, only disproof or falsification can logically be demonstrated. As a result, he proposes that ‘scientists’, in the ordinary sense of that word, ought to use a set of rules which ensure that their propositions are falsifiable and that propositions are accepted only if