ECAI 2004 Conference Paper

Extending Defeasible Logic and Defeasible Prolog

Ahti-Veikko Pietarinen

Defeasible logic promotes enthymemic, argumentative reasoning on incomplete set of premisses that are retracted on the presence of contrary information. Defeasible Prolog (d-Prolog) is a Prolog metainterpreter designed by Donald Nute to implement nonmonotonic inference based on a system of defeasible logic. In this paper, it is shown how to give proof conditions for the 'even-if' conditions of defeasible logic. This is done by allowing the pre-emption of defeaters, in other words by preventing some rules from rebutting other, more specific rules. These proof conditions are implemented to d-Prolog. Computational results are presented for the given examples, and fundamental goals of defeasible reasoning are assessed.

Keywords: Logic Programming, Nonmonotonic Reasoning

Citation: Ahti-Veikko Pietarinen: Extending Defeasible Logic and Defeasible Prolog. In R.López de Mántaras and L.Saitta (eds.): ECAI2004, Proceedings of the 16th European Conference on Artificial Intelligence, IOS Press, Amsterdam, 2004, pp.1075-1076.

ECAI-2004 is organised by the European Coordinating Committee for Artificial Intelligence (ECCAI) and hosted by the Universitat Politècnica de València on behalf of Asociación Española de Inteligencia Artificial (AEPIA) and Associació Catalana d'Intel-ligència Artificial (ACIA).