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)