Children, like grown-ups, enjoy the sense of achievement derived from mastering a difficulty, but this requires a consistency of effort of which few are capable without some outside encouragement. The capacity for consistent self-direction is one of the most valuable that a human being can possess. It is practically unknown in young children, and is never developed either by a very rigid discipline or by complete freedom.

Bertrand Russell (1872–1970) English mathematician and philosopher

Education and the Social Order [Education and the Modern World], ch. 2 “The Negative Theory of Education” (1932)
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