One of the interesting differences between high art and great science is that the former is both unique and its emergence unpredictable in a way that is not quite true of the latter. If Newton had not lived, I have seen it argued, Huygens and Leibniz would have gone on to do his principal work; Wallace was closing in on the theory of evolution for which Darwin has since been recognized as a hero of science; and Edison's work could as readily have been done by Swan (on the incandescent lamp) and Hughes (on the microphone), or so it is said. If Albert Einstein had never lived, it is possible that Ernst Mach or Max Planck or another German physicist would have set to work on the problem of relativity; but if Proust had died in his twenties, there would be no Remembrance of Things Past, nor, it...