Actions with Indirect Effects (Extended Abstract)
Enrico Giunchiglia, Gopinath Kartha, Vladimir Lifschitz · 1995
) Enrico Giunchiglia, G. Neelakantan Kartha and Vladimir Lifschitz Department of Computer Sciences University of Texas at Austin Austin, Texas 78712 fenrico,kartha,[email protected] 1 Introduction Our goal is to extend and improve the action language AR 0 proposed in [ Kartha and Lifschitz, 1994 ] and to simplify the method for representing actions with indirect effects in circumscriptive theories described in that paper. The new action language AR differs from AR 0 in two ways. First, AR allows us to represent fluents whose values are non-Boolean, such as Location(x) or Color(x). In the situation calculus, such fluents can be always eliminated in favor of propositional fluents, just as function symbols in first-order logic can be eliminated in favor of predicate symbols. For instance, instead of Brighter(Color(x; s1); Color(x; s2)) we can write 8c 1 c 2 [HasColor(x; c1; s1) HasColor(x; c2; s2) oe Brighter(c 1 ; c 2 )]: But this may be unnatural and inconvenient. Surprisi...