A Computational Method for Defeasible Argumentation Based on a Recursive Warrant Semantics

In a recent paper [2] the authors have formalized a recursive semantics for warranted conclusions in a general defeasible argumentation framework based on a propositional logic. The warrant recursive semantics is based on a general notion of collective (non-binary) conflict among arguments allowing to ensure direct and indirect consistency properties. This general framework was also extended by allowing levels of defeasibility and providing a level-wise recursive definition of warranted and blocked conclusions. In this paper we focus on the particular framework of Defeasible Logic Programming (DeLP) extended with levels of defeasibility for which we characterize programs with a unique output (extension) for warranted conclusions, and we design, for this type of programs, an algorithm for computing warranted conclusions in polynomial space and with an upper bound on complexity equal to PNP .

• Type: Journal
• Year: 2010
• Where: IBERAMIA
• Authors: Teresa Alsinet, Ramón Béjar, Lluis Godo
• Keywords: Artificial Intelligence, Defeasible Argumentation Framework, Defeasible Logic Programming, IBERAMIA 2010, Level-wise Recursive Definition