Ought-Sentences and the Juristic Description of Rules

Abstract .
According to the normative theory of legal science, juristic ought-sentences describe rules, since legal science just deals with rules, and rules cannot be described but by means of ought-sentences. The author challenges this view. Two different constructions of "describing rules" are proposed: Namely, either interpreting or stating the validity of rules. "Interpreting rules," in its turn, can be understood in three different senses: listing all the possible meanings of rule-formulations, reporting the different interpretations a rule-formulation has in fact received by courts, or ascribing meaning to rule-formulations. However, the author argues that ought-sentences are not the proper tools to accomplish such tasks. At the same time, juristic ought-sentences cannot be understood as validity statements, since they neither mention any rule whatsoever, nor include the term "valid." Further, if validity-statements were ought-sentences, their logical behaviour would reflect the logic of rules themselves. However, as the late Kelsen argued, things do not run this way, since two inconsistent ought-sentences, if understood as validity statements, can paradoxically both be true, as well as both false. Hence, validity-statements cannot be reduced to ought-sentences iterating the rules which they (are supposed to) refer to.