A theory which is not refutable by any conceivable event is non-scientific.

Philosophers
Karl Popper
Austrian-British philosopher (1902-1994), a leading philosopher of science. He proposed falsifiability as the criterion of scientific status; The Open Society (1945) defended liberal democracy. Soros named him mentor.
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Source: ポパー『推測と反駁 (Conjectures and Refutations)』第1章 §1 (1963年)Verified
Karl Popper's Other Quotes
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