Every time we let ourselves believe for unworthy reasons, we weaken our powers of self-control, of doubting, of judicially and fairly weighing evidence. We all suffer severely enough from the maintenance and support of false beliefs and the fatally wrong actions which they lead to, and the evil born when one such belief is entertained is great and wide. But a greater and wider evil arises when the credulous character is maintained and supported, when a habit of believing for unworthy reasons is fostered and made permanent.

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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