 This view is foreshadowed both in Thomas Hobbes and John Locke, but its most influential contemporary version is due to Joseph Raz (1975 [1990: 35–84]). Raz argues that obligations are categorical reasons for action that are “protected” insofar as they are combined with special second-order reasons that require us to exclude from our deliberation some of the competing first order reasons for action. “First-order reasons” are normal reasons for action grounded in self-interest, desires or morality; “second-order reasons” are reasons that we have to act (or refrain from acting) on first-order reasons. Thus, the distinctive feature of obligations, according to Raz, is that they exclude some contrary reasons—typically at least reasons of convenience and ordinary preference—from our practical deliberation. Some but not all. An “exclusionary reason” is not necessarily a conclusive reason. The stringency of an obligation is thus a consequence not of its weight or practice features, but of the fact that it supports the required action by special normative means, insulating it from the general competition of reasons. Or at any rate this is what obligations do when they have the force they claim, i.e., when they are binding. The theory does not assume that all legal obligations actually are binding from the moral point of view, but it does suppose that the legal system puts them forth as if they were—a consequence that some have doubted (Hart 1982: 263–267; Himma 2001: 284–297). And while this account is invulnerable to the objections to sanction-based and practice-based theories, it does need to make good the general idea of an “exclusionary reason”, and some philosophers have expressed doubts on that score also.