 So, Kant concludes, in order to be necessarily true throughout their domain, the synthetic a priori propositions about space and time—and this includes not just the specific propositions of geometry or mathematics more generally but also the general propositions derived in the metaphysical expositions, such as that space and time are infinite singular wholes with parts rather than instances—must be true only of the representations on which we impose our own forms of intuition, and cannot be true of things as they are in themselves. This is Kant’s chief argument for transcendental idealism, the view that the way things appear to us essentially reflects our cognitive capacities rather anything intrinsic to them, combined with what we could call theoretically indeterminate ontological realism, the view that there are things independent of our representations of them but because our most fundamental ways of representing things cannot be true of them we cannot know anything about them other than this fact itself—until, that is, Kant brings his practical argument for our own ultimately mental nature and the mental nature of God on board.