Reasoning about permissions and obligations sometimes requires to distinguish more than one level of permission: certain actions are preferable to others, or one has more confiden...
Abstract. We show that a recently developed theory of positive permission based on the notion of derogation is hampered by a triviality result that indicates a problem with the und...
Abstract. To guarantee the security of computer systems, it is necessary to define security permissions to restrict the access to the systems' resources. These permissions enf...
We explain the raison d’ˆetre and basic ideas of input/output logic, sketching the central elements with pointers to other publications for detailed developments. The motivation...
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...
Guillaume Aucher, Davide Grossi, Andreas Herzig, E...