The man who proposes to write large-scale history should not be expected himself to do the spade work. In the sciences, this sort of thing is recognized. Kepler's laws were based upon the observations of Tycho Brahe. Clerk Maxwell's theories rested upon the experiments of Faraday. Einstein did not himself make the observations upon which his doctrines are based. Broadly speaking the amassing of facts is one thing, and the digesting of them is another.
Source: Bertrand Russell: History as an art (1954)
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