ON PRACTICES AND THE LAW

In a recent paper, “How Facts Make Law,” I launch an attack on a fundamental doctrine of legal positivism. I argue that nonnormative facts cannot themselves constitutively determine the content of the law. In a response published in this journal, Ram Neta defends the view that nonnormative social facts are sufficient to determine normative facts, including both moral and legal facts. Neta's paper provides a useful opportunity to address a spelled-out version of this view, which in various forms is widely held in philosophy of law and other areas of philosophy. I begin by addressing Neta's attempts to show that descriptive facts can alone determine moral and legal facts. First, Neta's account of why it is wrong to break promises fails. In addition to other problems, it begs the question by taking for granted that a person's desires or other motivational states necessarily justify the actions that they motivate. Next, I turn to Neta's attempt to provide a counterexample to my view about law. In my original paper, I claim that the nature of the constitutive determination relation in the legal domain is what I callrational determination. Roughly speaking, a full constitutive account of the legal facts must include reasons that explain the relation between the determining facts and the legal facts. The facts on which Neta's putative counterexample depends cannot be reasons of the required sort because they take for granted what they are supposed to explain—the way in which nonnormative social facts contribute to the content of the law. Finally, I address the larger issue of how far my argument applies to other domains. I consider and reject Neta's argument that purports to show that all normative domains have the relevant features of the legal domain. I then sketch a competing picture of some normative domains.