No man holding a strong belief on one side of a question, or even wishing to hold a belief on one side, can investigate it with such fairness and completeness as if he were really in doubt and unbiased; so that the existence of a belief not founded on fair inquiry unfits a man for the performance of this necessary duty.

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

“The Ethics of Belief,” Part 1 “The Duty of Inquiry,” Contemporary Review (Jan 1877)
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