In Memoriam: Karl Popper

Sir Karl Popper, the Austrian philosopher of science, died on September 17 in England at the age of 92. He was one of the major anti-authoritarians of our troubled century.

He was anti-authoritarian in his politics. In his 1945 two-volume work The Open Society and its Enemies, he explored and criticized with cogency and passion the totalitarian views of government and society inherent in the ideas of some of his philosophical predecessors, particularly Plato, Hegel, and Marx. He inveighed mightily against "historicism," a much-confused term that to Popper meant the notion that history evinces laws of development that dictate the singular purpose toward which it strives. Popper saw this idea inextricably linked with a totalitarian political temperament.

He was also anti-authoritarian in his epistemology, the field where he did much of his philosophical work. To Popper, there was no final authority for deciding truth–although he fervently believed that truth exists, and that the purpose of science is to strive to reach it. He cut the Gordian Knot of the problem of induction–the question of how it is that humans come to sure knowledge of universal laws based on individual experience.

Popper maintained that there was no such thing as induction; we do not come to sure knowledge of universal laws from collecting observations. We theorize first and always, and then attempt to test our theories against empirical observations. He is most widely known for his principle of falsification, the notion that the true test of a theory's scientific status is that some empirical evidence could refute it. To Popper, the advance of science required a never-ending series of conjectures and attempts at refutation. His role in the philosophy of science was to apotheosize the spirit of free criticism, a spirit central to the open society he championed.

Popper was not a doctrinaire libertarian. Though a long-time friend and correspondent of F.A. Hayek's, he embraced social safety nets and believed in the efficacy of what he called "piecemeal social engineering" to ameliorate social problems. But he did fight brave intellectual battles for greater freedom against the dominant trends in both political and scientific philosophy.

The spirit of free inquiry and an open society that Popper championed will go a long way toward ensuring that his often-expressed optimism about the future of freedom and civilization will be borne out.