## Autoepistemic Logic As A Unified Basis For Nonmonotonic Reasoning (1993)

Citations: | 5 - 1 self |

### BibTeX

@MISC{Niemelä93autoepistemiclogic,

author = {Ilkka Niemelä},

title = {Autoepistemic Logic As A Unified Basis For Nonmonotonic Reasoning},

year = {1993}

}

### OpenURL

### Abstract

Autoepistemic logic is investigated in a general setting where autoepistemic reasoning based on a given classical logic is studied. The possible sets of autoepistemic conclusions from a set of premises are defined in terms of expansions of the premises. First Moore style expansions defined by a fixed point equation are considered and a simple finitary characterization of expansions is developed. An alternative definition is proposed where autoepistemic reasoning is formalized as a sequence of introspection steps using an enumeration of sentences. The resulting enumeration-based expansions are a proper subclass of Moore style expansions. An even more tightly grounded subclass is captured by considering only L-hierarchic enumerations. Finitary characterizations of enumeration-based and L-hierarchic expansions are developed. It is shown that autoepistemic reasoning based on Moore style, enumeration-based, and L-hierarchic expansions is decidable if the monotonic consequence relation giv...