 Cohen sets the bar high. Given Copernicus’ own conservatism and the fact that few people paid attention to his work for half a century, the Copernican achievement was not a revolution by Cohen’s lights. Or if there was a revolution, should it not be attributed to Kepler, Galileo, and Descartes? This thought further problematizes the notion of revolution, for science studies experts as well as scientists themselves know that scientific and technological innovation can be extremely nonlinear in the sense that a seemingly small, rather ordinary development may eventually open up an entire new domain of research problems or a powerful new approach. Consider Planck’s semi-classical derivation of the empirical blackbody radiation law in 1900, which, under successively deeper theoretical derivations by himself and (mainly) others over the next two and a half decades, became a pillar of the revolutionary quantum theory. As Kuhn (1978) shows, despite the flood of later attributions to Planck, it is surprisingly difficult, on historical and philosophical grounds, to justify the claim that he either was, or saw himself as, a revolutionary in 1900 and for many years thereafter. (Kuhn 2000b offers a short summary.) Augustine Brannigan (1981) and Robert Olby (1985) defend similar claims about Mendel’s alleged discovery of Mendelian inheritance.