If I let myself believe anything on insufficient evidence, there may be no great harm done by the mere belief; it may be true after all, or I may never have occasion to exhibit it in outward acts. But I cannot help doing this great wrong towards Man, that I make myself credulous. The danger to society is not merely that it should believe wrong things, though that is great enough; but that it should become credulous, and lose the habit of testing things and inquiring into them; for then it must sink back into savagery.

William Kingdon Clifford (1845-1879) English mathematician and philosopher

“The Ethics of Belief,” Part 1 “The Duty of Inquiry,” Lecture, London (11 Apr 1876)
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