Abstract
On the reading of Kant's resolutions of the first two antinomies advanced here, Kant not only denies that the empirical world has a ground floor of empirical objects lacking proper parts in the resolution of the second antinomy, but he also denies that it has a ceiling consisting in a composite whole enclosing all other empirical objects in the resolution of the first antinomy. Indeed, the order of explanation in the first antinomy runs from wholes to the proper parts they spatially enclose, whereas the order of explanation runs in the opposite direction in the second antinomy. But this appears to involve viciously circular explanation, and hence to generate the problem of circular conditioning. Working out a solution to this problem involves closer investigation of Kant's account of real conditioning relations, and how these relations are connected to the structure of space and time.