 If there have been so many revolutions, then why did the world have to wait for Kuhn to see them? Because, he said, they are largely invisible. For, after a revolution, the winners rewrite the history of science to make it look as if the present paradigm is the brilliant but rational sequel to previous work. The implication is that only someone of Kuhn’s historical sensitivity could be expected to notice this. (Skeptical critics reply that Kuhn invented the problem for which he had a solution.) Indeed, in his large book on the history of the early quantum theory (Kuhn 1978), he moved the origin of the quantum theory revolution forward five years, from Planck in 1900 to Einstein and Ehrenfest in 1905. Revisionist historiography by whiggish scientists, he claimed, had smoothed out the actual history by crediting Planck with a solution that he actually rejected at the time to a problem that he did not then have—and by diminishing the truly radical contribution of Einstein. Kuhn’s move again raises the question whether the authors of a revolution must knowingly break from the received research tradition.