I In Leviathan Hobbes presents a definition of civillaw which he claims to contain "nothing that is not at first sight evident."1 He writes that "CIVILL LAW, Is to every Subject, those Rules, which the Commonwealth hath Commanded hirn, by Word, Writing, or other sufficient Sign of the Will, to make use of, for the Distinction of Right, and Wrong; that is to say, of what is contrary, and what is not contrary to the Rule."2 It seems to be a matter of consensus among commentators on Hobbes that this theory of law is quite straightforwardly a variety
oflegal positivism.3 H. L. A. Hart in The Concept 0/ Law treats Hobbes as a positivist; John Watkins describes Hobbes's theory as "peculiar in its ... stark legal positivism"; Brian Barry, though attempting to distance Hobbes's account of law from that presented by John Austin, does not suggest that Hobbes and Austin differ in their positivism; and the writers of three of the best recent commentaries on Hobbes, Jean Hampton, Gregory Kavka, and Sharon Lloyd, seem to think that it can be asserted with little argument that in Leviathan Hobbes was a legal positivist. 4
What, though, does it mean to assert that Hobbes's theory of law is a variety of positivism? Hampton suggests that it is a positivist view because "law is understood to depend on the sovereign's will. No matter what a law's content, no matter how unjust it seems, if it has been commanded by the sovereign, then and only then is it law."s Hampton seems to ascribe two characteristics to Hobbes's legal theory that mark it as a variety of positivism: first, that in Hobbes's theory the pedigree of a norm alone determines wh ether that norm is legally valid,6 and second, that there is a conceptual separation between law and morality such that the legal validity of an enactment does not depend on its moral content. Although both of these theses commonly appear in positivist theories of law, I shall, following Hart, David Lyons, Joseph Raz, and Jules Coleman, take the second to be the defining feature of legal positivism.7 All varieties of legal positivism, that is, necessarily adhere to the separability thesis: "There exists at least one conceivable rule of recognition (and therefore one possible legal system) that does not specify truth as a moral principle among the truth conditions for
848 Ethics July 1995 any proposition oflaw."s Hampton's view, then, is that Hobbes's legal theory entails the separability thesis: since all that is necessary for something to be a law is that it be the command of the sovereign, there are no moral constraints on the content of law that could preclude a sovereign's command from attaining the status oflaw. Hobbes's theory is therefore a variety of legal positivism.