 Another of Kuhn’s declared tasks in Structure was to solve the problem of social order for mature science, that is, how cohesive modern science (especially normal science) is possible (Barnes 1982, 2003). Yet another was to bring scientific discovery back into philosophical discussion by endogenizing it in his model, while denying the existence of a logic of discovery. Whereas the logical empiricists and Popper had excluded discovery issues from philosophy of science in favor of theory of confirmation or corroboration, Kuhn was critical of confirmation theory and supportive of historical and philosophical work on discovery. He argued that discoveries are temporally and cognitively structured and that they are an essential component of an epistemology of science. In Kuhnian normal science the problems are so well structured and the solutions so nearly guaranteed in terms of the resources of the paradigm that the problems reduce to puzzles (Nickles 2003b). Kuhn kept things under control there by denying that normal scientists seek essential innovation, for, as indicated above, major, unexpected discoveries threaten the extant paradigm and hence threaten crisis and revolution. So, even in normal science, Kuhn had to admit that major discoveries are unexpected challenges to the reigning paradigm. They are anomalous, even exogenous in the sense that they come as shocks from outside the normal system.