Evaluating Epistemic Negation in Answer Set Programming (Extended Abstract).

Epistemic negation not along with default negation ¬ plays a key role in knowledge representation and nonmonotonic reasoning. However, the existing approaches behave not satisfactorily in that they suffer from the problems of unintended world views due to recursion through the epistemic modal operator K or M (K F and M F are shorthands for ¬not F and not ¬ F , respectively). In this paper we present a general approach to epistemic negation which is free of unintended world views and thus offers a solution to the long-standing problem of epistemic specifications which were introduced by [Gelfond, 1991] over two decades ago.