And if individuals are to retain that measure of initiative and flexibility which they ought to have, they must not be all forced into one rigid mold; or, to change the metaphor, all drilled into one army. Diversity is essential in spite of the fact that it precludes universal acceptance of a single gospel. But to preach such a doctrine is difficult especially in arduous times. And perhaps it cannot be effective until some bitter lessons have been learned by tragic experience
Source: Bertrand Russell: Reflections on My Eightieth Birthday (1952)
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