A short life of the author
Sir Karl Raimund Popper CH FBA FRS (28 July 1902 – 17 September 1994) was an Austrian-born British philosopher of science and political theorist whose ideas fundamentally changed the way scientists, philosophers, and policymakers think about knowledge, scientific method, and political organisation. His principle of falsifiability — the idea that a scientific theory must be capable of being refuted by evidence — became the most widely accepted criterion for distinguishing science from non-science. His political philosophy, articulated in The Open Society and Its Enemies (1945), mounted one of the most powerful defences of liberal democracy against totalitarianism ever written.
Life
Popper was born in Vienna into a prosperous, assimilated Jewish family. His father was a lawyer with a large library; his mother was musical. He grew up in the intellectually explosive Vienna of the early twentieth century — the city of Freud, Wittgenstein, the Vienna Circle, Schoenberg, and Klimt. As a young man, he was briefly attracted to Marxism, then to individual psychology (he worked with Alfred Adler), and then to the philosophy of science through his engagement with the Vienna Circle, the group of logical positivists led by Moritz Schlick.
Popper was never a member of the Vienna Circle, and his relationship with its members was contentious. His first major work, Logik der Forschung (1934), was partly a response to the Circle’s verificationism — their claim that a statement is meaningful only if it can be empirically verified. Popper argued that this criterion was too strong (it excluded too much) and proposed falsifiability instead.
With the rise of Nazism, Popper — who was of Jewish descent — left Austria in 1937 for New Zealand, where he taught at Canterbury University College in Christchurch. He wrote The Open Society and Its Enemies during the war years. In 1946, he moved to England, where he spent the rest of his career at the London School of Economics, becoming professor of logic and scientific method.
The Logic of Scientific Discovery (1934 / 1959)
Popper’s central argument is deceptively simple: no amount of confirming evidence can prove a universal scientific theory true (you cannot observe all swans to prove “all swans are white”), but a single counterexample can prove it false (one black swan suffices). Therefore, the hallmark of a genuinely scientific theory is not that it can be verified but that it can, in principle, be falsified — that it makes predictions that could be shown to be wrong.
This criterion allowed Popper to draw a sharp line between science and what he called “pseudo-science.” He argued that Marxism and Freudian psychoanalysis, while presenting themselves as scientific theories, were in fact unfalsifiable: they could accommodate any possible observation and therefore explained nothing. Einstein’s general relativity, by contrast, made precise, risky predictions — and was therefore genuinely scientific.
The practical consequence of Popper’s philosophy is that science proceeds not by accumulating certainties but by proposing bold conjectures and subjecting them to severe tests. Progress comes through error elimination. This “conjectures and refutations” model has been enormously influential among working scientists, even as philosophers have debated its adequacy.
The Open Society and Its Enemies (1945)
Written in New Zealand during World War II, this two-volume work is one of the great polemics of the twentieth century. Popper traces the intellectual roots of totalitarianism back to Plato, Hegel, and Marx — thinkers who, he argued, shared a “historicist” belief that history follows predetermined laws and that the ideal society can be designed from first principles.
Against this, Popper defended the “open society” — a society that relies on critical discussion, piecemeal reform, democratic institutions, and the willingness to acknowledge error. The open society makes no claims to possess the truth; it creates institutional mechanisms for correcting mistakes. The closed society, by contrast, claims to know the direction of history and suppresses dissent in the name of progress.
The work’s influence extended far beyond philosophy. It was read by politicians, cited in Cold War debates, and invoked by George Soros, who named his philanthropic network the Open Society Foundations after Popper’s concept.
Legacy and Criticism
Popper’s falsificationism has been challenged by Thomas Kuhn (The Structure of Scientific Revolutions, 1962), who argued that scientists do not actually abandon theories when confronted with anomalies — they work within “paradigms” that resist falsification. Imre Lakatos and Paul Feyerabend, both Popper’s students, developed alternative philosophies of science that modified or rejected his framework. Popper and Kuhn engaged in a famous debate that remains unresolved.
Popper was notoriously combative, and his intellectual disputes — with the Vienna Circle, with Wittgenstein (the famous “poker incident” at Cambridge), with Kuhn, with the Frankfurt School — were legendary.
Collecting Popper
Logik der Forschung (1934, Julius Springer, Vienna) in first German edition is rare and brings $1,000–$5,000. The Open Society and Its Enemies (1945, Routledge) in first edition brings $300–$1,500. The English translation, The Logic of Scientific Discovery (1959, Hutchinson), brings $100–$400. Signed copies are available but not common.