Extending Prolog with Nonmonotonic Reasoning

Nonmonotonic reasoning has been developed to capture common sense inferences. This paper considers nonmonotonic reasoning in logic programs with negation { its implementation using Prolog and its integration with Prolog execution. Even within logic programming frameworks, a variety of inferencing methods, model-theoretic semantics, and language features have been proposed for diierent forms of nonmonotonic reasoning. A challenging problem is to incorporate them into an integrated system. This paper describes an implementation of such a system, including the interoperation between Prolog execution and tabled evaluation, and diierent reasoning capabilities that are supported. By combining Prolog technology with various mechanisms of nonmonotonic reasoning, the resulting system ooers a more realistic testbed for applications of common sense reasoning.