Since 1976 Hilary Putnam has drawn parallels between his "internal", "pragmatic", "natural" or "common-sense" realism and Kant's transcendental idealism. Putnam reads Kant as rejecting the then current metaphysical picture with its in-built assumptions of a unique, mind-independent world, and truth understood as correspondence between the mind and that ready-made world. Putnam reads Kant as overcoming the false dichotomies inherent in that picture and even finds some glimmerings of conceptual relativity in Kant's proposed solution. Furthermore, Putnam reads Kant as overcoming the (...) pernicious scientific realist distinction between primary and secondary qualities, between things that really exist and their projections, a distinction that haunts modern philosophy. Putnam's revitalisation of Kant is not just of historical interest, but challenges contemporary versions of scientific realism. Furthermore, Putnam has highlighted themes which have not received the attention they deserve in Kantian exegesis, namely, the problematic role of primary and secondary qualities in Kant's empirical realism, and the extent of Kant's commitment to conceptual pluralism.However, I argue that Putnam's qualified allegiance to Kant exposes him to some of the same metaphysical problems that affected Kant, namely, the familiar problem of postulating an absolute reality (Ding an sich), while at the same time disavowing the meaningfulness of so doing. In conclusion I suggest that Putnam might consider Hegel's attempts to solve this problem in Kant as a way of furthering his own natural realism. (shrink)