Perhaps the most useful lesson the student of history can learn is to avoid oversimplification, and to accept the notion of multiple causation or to resign himself to the fact that as yet we do not know enough to explain the causes of things. To yearn for a single, and usually simple, explanation of the chaotic materials of the past, to search for a single thread in the most tangled of all skeins, is a sign of immaturity.
Henry Steele Commager (1902-1998) American historian, writer, activist
The Nature and the Study of History, ch. 5 (1965)
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