Nearly all philosophers of law agree that nonnormative, nonevaluative, contingent facts—descriptive facts, for short—are among the determinants of the content of the law. In particular, ordinary empirical facts about the behavior and mental states of people such as legislators, judges, other government officials, and voters play a part in determining that content. It is highly controversial, however, whether the relevant descriptive facts, which we can call law-determining practices, or law practices (or simply practices) for short, are the only determinants of legal content, or whether legal content also depends on normative or evaluative facts—value facts, for short. In fact, a central—perhaps the central—debate in the philosophy of law is a debate over whether value facts are among the determinants of the content of the law (though the debate is not usually characterized in this way).