 The first Critique argues that there has hitherto been no real progress in metaphysics. In the second edition Preface, Kant proudly proclaims that his book has finally put metaphysics on “the sure path of a science” (Bvii; cf. Axiii). What, then, is the relation of metaphysics—or philosophical reasoning more generally—to those areas of human enquiry that do seem to generate certainty (geometry and mathematics) and the expansion of knowledge (science in general)?