Dynamic context logic and its application to norm change

Building on a simple modal logic of context, the paper presents a dynamic logic characterizing operations of contraction and expansion on theories. We investigate the mathematical properties of the logic, and use it to develop an axiomatic and semantic analysis of norm change in normative systems. The proposed analysis advances the state of the art by providing a formal semantics of norm-change which, at the same time, takes into account several different aspects of the phenomenon, such as permission and obligation dynamics, as well as the dynamics of classificatory rules.