Kant claims that an indirect proof of transcendental idealism is furnished by the “Antinomy of Pure Reason,” the second of the three “Dialectical Inferences of Pure Reason” (A 338 / B 396), the discussion of which comprises the bulk of the “Transcendental Dialectic” of the Critique of Pure Reason. On the assumption that things as they are in themselves really are spatial and temporal, he argues, reason is necessarily ensnared in paradoxes, certainly those concerning the upper and lower bounds of spatial and temporal extent, the infinite, and atoms, which had plagued philosophers since Zeno and which had been pressed with renewed vigor in Kant's time by Bayle and Hume, but also the paradoxes about causality and freedom, both human and divine, which had given Leibniz such trouble. But on the assumption that space and time are merely features of our representations of objects but not of the objects themselves, Kant claims, and only on this assumption, these paradoxes can be avoided. As he puts it in the preface to the second edition of the Critique, the pretension of traditional metaphysics to transcend the limits of possible experience