The sceptic holds that the truth is undiscoverable, while the dogmatist holds that it is already discovered. The man of science holds that the truth is discoverable though not discovered, at any rate in the matters which he is investigating. But even to say that the truth is discoverable is to say rather more than the genuine man of science believes, since he does not conceive his discoveries as final and absolute, but as approximations subject to future correction. Absence of finality is of the essence of the scientific spirit.

Bertrand Russell (1872–1970) English mathematician and philosopher

Education and the Social Order [Education and the Modern World], ch. 1 “The Individual versus the Citizen” (1932)
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