In science, “fact” can only mean “confirmed to such a degree that it would be perverse to withhold provisional assent.” I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.

Stephen Jay Gould (1941–2002) American paleontologist, geologist, biologist

“Evolution as Fact and Theory” in Speak Out Against the New Right [ed. Herbert Vetter] (1982)

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