What is less recognized is that we all suffer, to a greater or less degree, from nervous disorders having an emotional origin. A man is called sane when he is as sane as the average of his contemporaries; but in the average man many of the mechanisms which determine his opinions and actions are quite fantastic, so much so that in a world of real sanity they would be called insane.

Bertrand Russell (1872–1970) English mathematician and philosopher

Education and the Social Order [Education and the Modern World], ch. 4 “Emotion and Discipline” (1932)
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