Theoretical Disagreement and the Semantic Sting

Scott Shapiro recently suggested that Ronald Dworkin's critique in Chapter 1 of Law's Empire represents the greatest threat currently facing legal positivism. Shapiro had in mind, not the semantic sting argument ('the SSA'), but rather what I call 'the argument from theoretical disagreement' (or 'the ATD'). I contend that Shapiro was right to focus on the ATD, but that even he underestimated just how serious a challenge it poses to positivism (and perhaps to other theories of law as well). The ATD, I argue, is an objection to any theory of law that denies that legal officials can engage in theoretical disagreement-that is, disagreement about the grounds of law. The SSA then seeks to explain why so many legal philosophers adopt such theories. I argue that the SSA is an implausible explanation of why many legal philosophers deny that theoretical disagreement exists, but that this does not undermine the ATD's contention that they are wrong to do so. Indeed, given the variety of forms that theoretical disagreement can take, Dworkin's positivist critics face a very significant challenge in seeking either to explain away the appearance of theoretical disagreement or to develop forms of positivism that can allow for such disagreement