Abstract.The author gives a short survey of the different methods which have been proposed to deal with the logic of norm sentences on the basis of logical systems of descriptive language: deontic logic, logic of norms as an isomorphism of propositional logic, restriction of logical relations to the propositional content of norm sentences, transformation of norms into sanction sentences, preference interpretation of norm sentences, double interpretation of ought‐sentences and the use of the descriptive interpretation as a tool for establishing the (...) logic of norms, proposition about norms in the place of normative logic, the logic of admissible worlds, postulates addressed to the rational lawgiver and technical ought as a substitute for nor‐mological considerations. A critical analysis of these attempts may prove them inappropriate, but it is not sufficient to prove the impossibility of any method of founding normative logic on systems of a descriptive language. Therefore the author adds a general consideration on the chances of such approaches. (shrink)

Abstract.One of the theses of the present work is that, at the strictly logical and methodological level, practical logic has neither made, nor can it make any contribution to the philosophy of law, since none of the three branches of practical logic that have been taken into account, namely, the logic of norms, deontic logic and legal logic, seems to be theoretically possible. The contribution of practical logic to the analysis of legal language is assessed in terms of both the (...) instruments of analysis elaborated by practical logic, the artificial languages, and the results obtained in two capital subjects, the negations of norms and the permissions. (shrink)