 Dworkin [1986] considered identification of the grounds of law the central question for the philosophy of law. The grounds of law identify the truth conditions of propositions of law. The doctrinal concept of law answered this question. For him, the jurisprudential debate thus focused on whether the grounds of law included moral principles or not. Implicitly, then, Dworkin interpreted Hart [1961] as centrally addressing this doctrinal question. 