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Popper, Sir Karl


POPPER, SIR KARL (Raimund ; 1902–1994), philosopher. Popper was born in Vienna of Jewish parents who had converted to Christianity. In the early 1920s he worked with juvenile delinquents in Alfred *Adler's clinic in Vienna. In 1930 he became a secondary school teacher of mathematics and science. The rise of Fascism led to his leaving Austria in 1937, and until 1945 he taught philosophy at Canterbury University College, New Zealand, where he wrote The Open Society and Its Enemies. He then moved to the University of London, and in 1949 became professor of logic and scientific method at the London School of Economics. He was knighted in 1965, and in 1982 was made a Companion of Honour (ch). Popper's philosophical views were profoundly influenced by the Einsteinian revolution in physics.

As early as 1919 Popper began to draw the philosophical consequences of this revolution. He saw that the "inductive method," hitherto supposed to be the distinguishing mark of science, was a myth. Empirical evidence was used in science, not to establish cautious hypotheses, which is impossible, but to refute bold ones. The mark of a scientific theory was its refutability, and the scientific pretensions of those other contemporary revolutions in thought, the theories of *Marx, *Freud, and Adler, were suspect on this count. Popper's revolutionary philosophy of science was eventually published in Die Logik der Forschung (1934; The Logic of Scientific Discovery, 1959). He had close contact in these early years with the logical positivist movement. He criticized the postivists' inductivism, and their attempt to dismiss all metaphysics as meaningless. This, he argued, ignored the suggestive value of many metaphysical ideas for science. Popper wrote The Open Society and Its Enemies (2 vols., 1945, 1965), which criticized the authoritarian political philosophies then in vogue. He attacked their belief in the inexorable laws of history, and the idea that the task of the social sciences was to discern these laws and to prophesy the future development of society. His elaboration of these criticisms, and his positive views on the method of the social sciences, later appeared in his book The Poverty of Historicism (1957). From the time Popper began working in England a stream of articles issued forth, witnessing to his new, more metaphysical interests in such things as indeterminism and emergent evolutionism. A collection of these, entitled Conjectures and Refutations: The Growth of Scientific Knowledge, appeared in 1963. Popper also wrote an interesting autobiography, Unended Quest (1976). Popper's influence, through his fertile and original contributions to a wide variety of problems, has been great: his concept of critical fallibilism is an important trend in contemporary philosophy. His view that to be scientific a theory must be falsifiable, and his insistence that the so-called "scientific socialism" of Marxism is not scientific, have had profound effects upon postwar Western thought. Popper is often grouped with such influential writers in Britain as George Orwell and Frederick von Hayek whose key works, which also appeared in the mid-late 1940s, undermined the intellectual attractiveness of Marxism in the West and, eventually, everywhere.


M.A. Bunge (ed.), Critical Approach to Science and Philosophy (1964), incl. his bibl.; K. Popper, in: C.A. Mace (ed.), British Philosophy in the Mid-Century (1957), 155–91 (philosophical autobiography); P. Edwards (ed.), Encyclopedia of Philosophy (1967), index. add. bibliography: M.H. Hacohen, Karl Popper: The Formative Years, 1902–1945 (2000).

[Alan E. Musgrave]

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