On influence and contractions in defeasible logic programming

Abstract

In this paper, we investigate the problem of contraction in Defeasible Logic Programming (DeLP), a logic-based approach for defeasible argumentation. We develop different notions of contraction based on both, the different forms of entailment implicitly existent in argumentation-based formalisms and the influence literals exhibit in the reasoning process. We give translations of widely accepted rationality postulates for belief contraction to our framework. Moreover we discuss on the applicability of contraction for defeasible argumentation and the role of influence in this matter. © 2011 Springer-Verlag Berlin Heidelberg.