This paper aims to explore two objections raised against Bulygin’s second approach to the definition of the nature of legal power-conferring rules. According to the first objection, such an account is vague about what is defined by legal power-conferring rules qua constitutive rules. I maintain that this vagueness is rooted in the lack of a suitable definition of legal power. I shall be arguing for the reduction of the complexity of the definientia by defining legal power as a species of (...) competence. According to the second objection, this non-reductive approach cannot explain the normativity of this kind of rules. Against this approach, it argues that legal powerconferring rules perform a deontic and a definitional function as constitutive rules of legal practice. (shrink)

Dialogues and dialectics have come to playan important role in the field of ArtificialIntelligence and Law. This paper describes thelegal-theoretical and logical background of this role,and discusses the different services into whichdialogues are put. These services include:characterising logical operators, modelling thedefeasibility of legal reasoning, providing the basisfor legal justification and identifying legal issues,and establishing the law in concrete cases. Specialattention is given to the requirements oflaw-establishing dialogues.

The author investigates how the conception of legal validity as a specific mode of existence, adopted by Kelsen in Allgemeine Theorie der Normen (General Theory of Norms), can be reconciled with a conception of the legal system in which conflicts of legal norms remain of logical concern. To this end he makes use of Ludwig Wittgenstein's picture theory of the proposition as set out in the Tractatus Logico-Philosophicus. The conclusion is that in order to reconcile the two conceptions, the legal (...) system itself must be conceived of as consisting of three sub-systems, namely, (i) a sub-system of perceptible legal judgments, (ii) a sub-system of valid legal conditions, and (iii) a sub-system of observable social practices. (shrink)