A computational framework for institutional agency

This paper provides a computational framework, based on Defeasible Logic, to capture some aspects of institutional agency. Our background is Kanger-Lindahl-P\"orn account of organised interaction, which describes this interaction within a multi-modal logical setting. This work focuses in particular on the notions of counts-as link and on those of attempt and of personal and direct action to realise states of affairs. We show how standard Defeasible Logic can be extended to represent these concepts: the resulting system preserves some basic properties commonly attributed to them. In addition, the framework enjoys nice computational properties, as it turns out that the extension of any theory can be computed in time linear to the size of the theory itself

Obligation change in dependence logic and situation calculus

Also part of the Lecture Notes in Artificial Intelligence book sub series (LNAI, volume 3065)International audienceObligation change raises the ”frame problem” which is to characterise what obligations remain unchanged after an action has been performed. Many general solutions have been proposed but even if they are attractive from a thoretical point of view they have practical drawbacks. In this paper simple solutions are proposed thanks to the restriction to obligations that take the form of modal literals. These solutions are presented in the framework of dependence logic and of situation calculus, and it is shown that they are based on the same intuitive idea. This idea is to express that we have a complete representation of actions and circumstances that can change an obligation