Herbert Hart's significance can be understood only when his work is measured against conceptions of political philosophy that were dominant in Oxford in the years between his postwar return and the publication of The Concept of Law. In Hart's own terminology, the central case of morality understood from the internal point of view is critical, that is, justified, morality. Hart's exclusive focus on positive morality cut the debate off from the main political-philosophic tradition, and from reason. That Hart had a political philosophy at all was an act of conscious resistance to skepticism. Yet the resistance was itself shaped and limited by Hart's own skepticism about something more foundational: the truth-value, and truth, of moral judgments intended as critical because asserted as true, sound, really justified. Hart criticized On Liberty for relying on a presumption of middle-aged psychological caution and stability to justify rejecting paternalism.