Whatever may be thought of a social system which tolerates slavery, it is to gentlemen in the above sense that we owe pure mathematics.
 Bertrand Russell, A History of Western Philosophy (1945). copy citation

Context

“It should be observed that this definition includes the saint and the sage, insofar as these men’s lives are contemplative rather than active.
Modern definitions of truth, such as those of pragmatism and instrumentalism, which are practical rather than contemplative, are inspired by industrialism as opposed to aristocracy.
Whatever may be thought of a social system which tolerates slavery, it is to gentlemen in the above sense that we owe pure mathematics. The contemplative ideal, since it led to the creation of pure mathematics, was the source of a useful activity; this increased its prestige, and gave it a success in theology, in ethics, and in philosophy, which it might not otherwise have enjoyed.
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