 Thus Kuhn’s new emphasis is on synchronic revolutions, in which a field splits into subfields, rather than on the diachronic replacement of one paradigm complex by another that his early account featured. His conception of a science is therefore less monolithic. A vibrant field such as evolutionary biology can tolerate several distinct species concepts at the same time, a fact that contributes rather than detracts from its vibrancy. The overall result is a less tightly integrated, less dogmatic conception of normal science under an overarching paradigm, a view that has implications also for the necessity and size of future revolutions. For no longer need an esoteric discrepancy get the leverage to trigger a crisis that eventuates in the replacement of an entire, tightly integrated system. In this respect, Kuhn’s conception of physics becomes somewhat closer to Godfrey-Smith’s characterization of progress in biology as “a deluge” rather than a full-scale Kuhnian revolution (see below and Godfrey-Smith 2007). Given that progress in biological evolution is better regarded as the remarkable proliferation of intricate, useful design rather than movement toward a goal, the explicit parallels that Kuhn draws to biological evolution suggest that he is moving toward the same conception of scientific progress as some see in biological evolution—as the proliferation of adaptive design. We may know more about his final position once more of the book manuscript, left incomplete at his death, is published.