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Popper

Original nameKarl Popper

Austrian-Born Philosopher, Proposer of Falsificationist Philosophy of Science

Those Who Reanswered "How Should We Live" · Modern & Contemporary Thinkers

FalsificationismPhilosophy of ScienceThe Open Society

Who they are

Karl Popper (1902–1994) was a Vienna-born philosopher, proposer of "falsificationism" in the philosophy of science. To the "demarcation problem" of "what kind of theory counts as truly scientific," he offered a revolutionary answer: a theory is scientific not by how much evidence can be found to support it (since almost any theory can find some degree of supporting evidence), but by whether it possesses "falsifiability" — whether it can clearly specify what kind of observation would refute it. By this standard he placed Marxist historical determinism and Freudian psychoanalysis outside strict science, holding that both theoretical frameworks have an "excessive elasticity" that can adjust themselves at any time to fit any counterexample, and so cannot truly be falsified. In political philosophy his chief work The Open Society and Its Enemies criticized Plato’s conception of the "philosopher-king," Hegel’s historical determinism, and Marxism together as the utopian engineering of "historicism," holding that only an "open society" permitting continual criticism, trial and error, and gradual reform can effectively avoid the catastrophe of totalitarianism.

Primary sourcesPopper, The Logic of Scientific Discovery, The Open Society and Its Enemies

Key stories

The Demarcation Standard of "Falsifiability"

Popper held that Einstein’s general relativity is a truly scientific theory precisely because it made concrete, bold, refutable predictions (such as that light passing near the sun would bend by a specific angle), and that Eddington’s 1919 eclipse observation could indeed have falsified this prediction (though it in the end confirmed it); by contrast, Freud’s psychoanalysis seemed always able to explain itself and fit any patient case into its framework, and this "never-wrong" elasticity exposes precisely its unscientific character.

The Poker Incident

In 1946 Popper, invited to speak at a Cambridge seminar on "whether genuine philosophical problems exist," clashed fiercely with Wittgenstein, who is said to have brandished a fireplace poker in agitation while pressing him, then stormed out — a dramatic scene later written up in the book Wittgenstein’s Poker, one of the most widely told scholarly anecdotes in twentieth-century philosophy.

Relationships

Nemesis

🗣️Wittgenstein　The two had the famous "poker" clash at a Cambridge seminar 🌀Hegel　In The Open Society and Its Enemies he criticized Hegel’s historical determinism as a breeding ground for totalitarianism

Echoes today

Below are how modern works borrow or reinterpret this name or story — not the original material. The two differ, so keep them apart.

"Falsifiability" (a term in scientific methodology)Still one of the core standards in modern philosophy-of-science education for judging whether a theory is scientific.

Appears in

The Twentieth Century: Analytic Philosophy and Scientific ReasonPopper’s "Falsifiability" and the Poker Incident

⏳ Who lived at the same time as Popper? →🔗 Who taught whom →

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