Abstract (EN)

Studying normative change is of practical and theoretical interest. Changing legal rules pose interpretation problems in determining the content of legal rules. The question of interpretation is tightly linked to questions about determining the validity of rules and their ability to produce effects. Different formal models of normative change seem to be better suited to capturing these different dimensions: the dimension of validity appears to be better captured by the AGM approach, while syntactic methods are better suited to modelling how the effects of rules are blocked or enabled. Historically, the AGM approach to belief revision (on which we focus in this article) was the first formal model of normative change. We provide a survey of the AGM approach along with the main criticisms of it. We then turn to a formal analysis of normative change that combines AGM theory and input/output logic, thereby allowing a clear distinction between norms and obligations. Our approach addresses some of the difficulties of normative change, like combining constitutive and regulative rules (and the normative conflicts that may arise from such a combination), revision and contraction of normative systems, as well as contraction of normative systems that combine sets of constitutive and regulative rules. We end our article by highlighting and discussing some challenges and open problems with the AGM approach regarding normative change.