Few scientists, or philosophers, have patience for a priori science. It is widely supposed that modern science owes its progress to subjecting hypotheses to experimental tests, and that nature is simply too intricate and surprising to determine without empirical investigation. Philosophers who have tried to study issues of substantial scientific doctrine or theory are regarded as embarrassments, and recent philosophers of science have narrowed their vision to scientific method. Probably no philosopher is more embarrassing than Hegel because he couples a priori science with a dialectical method that purports to derive concepts from each other in ways that bear no connection with either experience or material processes. Some contemporary scholars emphasize the empirical elements in his text, hoping, perhaps, to make his philosophy of nature more palatable against the long tide of philosophers who quickly dismiss his philosophy of nature. In my view, the current antipathy toward a priori science is misplaced: many great scientific achievements came from thinking through the implications of concepts through so-called thought experiments and other modes of nonempirical or, at least, not wholly empirical inference. Be that as it may, my concern here is Hegel's account of mechanics and, in particular, his criticism of Newtonian mechanics. I argue that Hegel not only discovered a contradiction in Newton or, rather, in Newton plausibly interpreted, but proposed a solution that carried the day in its tenor if not in its substance. Whether the solution was accepted because of Hegel is an historical question that I cannot address here.