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Representation Theory for Default Logic

Victor Marek·Jan Treur·Miroslaw Truszczynski
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Abstract

Default logic can be regarded as a mechanism to represent families of belief sets of a reasoning agent. As such, it is inherently second-order. In this paper, we study the problem of representability of a family of theories as the set of extensions of a default theory. We give a complete solution to the representability by means of normal default theories. We obtain partial results on representability by arbitrary default theories. We construct examples of denumerable families of non-including theories that are not representable. We also study the concept of equivalence between default theories.

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Victor Marek, Jan Treur, Miroslaw Truszczynski. 1999-01-28. Representation Theory for Default Logic. https://arxiv.org/abs/cs/9901016

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