MAN, some modern philosophers tell us, is alienated from his world: he is a stranger and afraid in a world he never made. Perhaps he is; yet so are animals, and even plants. They too were born, long ago, into a physico-chemical world, a world they never made. But although they did not make their world, these living things changed it beyond all recognition and, indeed, remade the small corner of the universe into which they were born. Perhaps the greatest of these changes was made by the plants. They radically transformed the chemical composition of the earth's whole atmosphere. Next in magnitude are perhaps the achievements of some marine animals which built coral reefs and islands and mountain ranges of limestone. Last came man, who for a long time did not change his environment in any remarkable way, apart from contributing, by deforestation, to the spread of the desert. Of course, he did build a few pyramids; but only during the last century or so , did he begin to compete with the reef-building corals. Still more recently he began to undo the work of the plants by slightly, though significantly, raising the carbon dioxide content of the atmosphere.

Anthony O'Hear's An Introduction to the Philosophy of Science is an excellent book; but the purpose here is not a general review. Instead, there is one important point that will be considered, where O'Hear settles on what seems to be a decisive criticism of Karl Popper's theory of falsification as the key to scientific method.

E' noto come il problema della legittimazione scientifica di una teoria viene posto in forma radicale e innovatrice da Popper. Egli stesso racconta come la concezione Freudiana, cui si era accostato lavorando con Adler, ebbe un ruolo essenziale nello spingerlo alla individuazione di un criterio di demarcazione: "Fu durante l'estate del 1919 che cominciai a sentirmi sempre più insoddisfatto di queste tre teorie: la teoria marxista della storia, la psicoanalisi e la psicologia individuale; e cominciai a dubitare delle loro pretese di scientificità. Il mio problema dapprima assunse, forse, la semplice forma: 'che cosa non va nel marxismo, nella psicoanalisi e nella psicologia individuale? Perché queste dottrine sono così diverse dalle teorie fisiche, dalla teoria newtoniana e, soprattutto dalla teoria della relatività?'".

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Popperian Ideas on Progress and Rationality in Science References Author Contact Information Copyright Retrieval About The Critical Rationalist

The most important philosopher of science since Francis Bacon (1561-1626), Sir Karl Popper finally solved the puzzle of scientific method, which in practice had never seemed to conform to the principles or logic described by Bacon -- see The Great Devonian Controversy, by Martin J. S. Rudwick, for a case study of Baconian rhetoric and expectations being contradicted by actual practice and results. Instead of scientific knowledge being discovered and verified by way of inductive generalizations, leaping from perceptual data into blank minds, in terms that go back to Aristotle, Popper realized that science advances instead by deductive falsification through a process of "conjectures and refutations