It has long been common for scholars to maintain that the science of Galileo posed most of the central philosophical and methodological problems for early modern philosophy. Historians as diverse in orientation as Whewell and Mach, Koyré, and Cassirer have seen in Galilean physics the roots of the major philosophical problems of early modern science.¹ Doubtless, there are some very important philosophical issues raised by Galilean physics (among them: why nature is quantifiable, the role of ideal cases in physical theory, the character of thought experiments). But it is seriously misleading historically to assert that the philosophical issues implicit in Galileo's mechanics — or in any science like Galileo's mechanics — were the central source of intellectual Angst for scientifically-minded philosophers of the 17th and early 18th centuries. I shall suggest briefly and tentatively that we must look elsewhere in the scientific revolution to find those doctrines about nature which were responsible for the chief features of the "epistemological revolution" of the early modern era.