SOURCE: "The Ascent of Nature in Darwin's Descent of Man," in The Darwinian Heritage, edited by David Kohn, Princeton University Press, 1985, pp. 283-306.

In the following essay, Durant studies the development of Darwin's arguments for the transmutation of human beings through sexual and natural selection in The Descent of Man.

What a chance it has been . . . that has made a man.

(Darwin, E Notebook, 68-69)

It is a fact familiar to all historians of science that Darwin was extremely slow to put his most important ideas into print. Having become a convinced transmutationist in 1837, he made such rapid progress over the next few years that he soon foresaw the prospect of writing a work that would revolutionize natural history. Yet it was not until 1844 that he produced an essay that was suitable for publication by his family in the event of his death; and fourteen years later, the...