   It would be a mistake, however, to look for an explanation of Kelsen’s argument in the logic of Kant’s transcendental argument. (Kelsen himself seems to have changed his views about this over the years; he may have started with a kind of neo-Kantian perspective one can discern in PT1, and gradually shifted to a Humean version of his main argument, which is quite evident in GT. However, this is a very controversial issue; for a different view, see Paulson 2013 and Green 2016.) Kant employed a transcendental argument to establish the necessary presuppositions of some categories and modes of perception that are essential for rational cognition, or so he thought. They form deep, universal, and necessary features of human cognition. Suffice it to recall that it was Hume’s skepticism about knowledge that Kant strove to answer by his transcendental argument. Kelsen, however, remains much closer to Hume’s skeptical views than to Kant’s rationalism. In particular, Kelsen was very skeptical of any objective grounding of morality, Kant’s moral theory included. Kelsen’s view of morality was relativist all the way down. (More on this, below). Second, and not unrelated, as we shall see, Kelsen has explicitly rejected the idea that the basic norm (in law, or of any other normative domain) is something like a necessary feature or category of human cognition. The presupposition of a basic norm is optional. One does not have to accept the normativity of law; anarchism, as a rejection of law’s normative validity is certainly an option, Kelsen maintained. The basic norm is presupposed only by those who accept the “ought”, that is, the normative validity, of the law. But one is not rationally compelled to have this attitude: