Legal Positivism discusses the autonomy of law in three directions: in respect of social and psychological facts; non-legal normativity, particularly morals; and other normative legal orders. In Kelsen’s Pure Theory, all three aspects are explicitly present. In the Hartian camp, the main emphasis is on the relationship between law and morals; especially on what has come to be called the separability thesis, which has sometimes been elevated to the core idea of Legal Positivism. Hartians have never been equally strict about the distinction between law and society; the Kelsenian dichotomy of Is and Ought has even been explicitly disclaimed. In the preface to The Concept of Law, Hart famously characterised his project as an exercise in descriptive sociology and, in the same vein, some contemporary Hartian positivists even declare the social-facts or social-sources thesis, instead of separability, the central tenet of Legal Positivism. The same theorists are wont to see an important difference from Dworkin in the social-facts thesis. Yet what the social-facts thesis actually boils down to is the claim of the rule of recognition as a social rule or a convention: legal validity ultimately depends on and is defined by a social rule; hence, the edifice of law rests on social facts. The way Hartians specify the rule of recognition and, for instance, demarcate legal validity from efficacy is remarkably similar to Kelsen’s treatment of the Grundnorm. In line with the Grundnorm, the rule of recognition, although itself breaking the separation of Is and Ought, produces autonomy in all three dimensions: in respect not only of morals and other legal orders but also of society and social facts. And because legal positivists derive the separability thesis from the rule of recognition as a social rule, the difference between the separability and social-facts theses as characterisations of the core of Legal Positivism vanishes.