A Modal Computational Framework for Default Reasoning
نویسندگان
چکیده
Usually a default rule A : B/C is intended to mean that if A holds in a state of affairs a B is consistent, then C follows by default. However, C is not a necessary conclusion: different states of affairs are possible (conceivable). According to this view, Meyer and van der Hoek [MvH92] developed a multimodal logic, called S5P(n), for treating non-monotonic reasoning in a monotonic setting. In this paper we shall describe a proof search algorithm for S5P(n) which has been implemented as a Prolog Interpreter. S5P(n) arises as a combination of S5 with n distinctK45 “preference” modalities Pi (1 ≤ i ≤ n) characterized by the following axioms:
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