A semantics for open normal defaults via a modified preferential approach
to derive existentially quantified formulae from other existentially quantified formulae by default,
to derive universally quantified formulae by default, and
to treat cardinality formulae analogously to other formulae.
Differing from previous approaches that do not satisfy all these properties, we will not view open defaults as schemata for certain instantiated defaults. Instead they will be used to define a preference relation on models. In modification of the usual approaches to preferential semantics we shall consider limits instead of minimal models.
KeywordsPreference Relation Minimal Model Default Rule Default Theory Ground Term
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