Abstract
According to Hans Kelsen, the basic norm is the necessary presupposition of the positivistic cognition of law, making possible both descriptive legal cognition and Verbindlichkeit. The nature of the presupposition in question here has been a subject of controversy ever since. Presupposing the basic norm gives rise to formulations that are neither purely descriptive nor purely normative. The author contends that Kelsen's doctrine of the basic norm was intended to apply to all jurists irrespective of function. Kelsen, without being aware of it initially, invested the verb “to presuppose” with an ambiguity that suits precisely this purpose.