d-Graph: an argument-based system incorporating defeasible graphs

We describe a tool to help users construct and explore graphs representing possibly incomplete or uncertain relations between propositions in a domain of interest selected by the user. The inference engine for this argument-based system (ABS) is derived from defeasible logic. Our prototype ABS implements a modification of an algorithm for reasoning with these graphs first reported in (Nute and Erk, 1996). We also report improved soundness and completeness results of the sort found in (Nute and Erk, 1996)