I do not approve the maxim which desires a man to know a little of everything. Superficial knowledge, knowledge without principles, is almost always useless and sometimes harmful knowledge.

Luc de Clapiers, Marquis de Vauvenargues (1715-1747) French moralist, essayist, soldier

Reflections and Maxims [Réflexions et maximes] (1746) [tr. Lee (1903)]
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