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Next: OBJECTIVES OF SITUATION CALCULUS

Combining Narratives

John McCarthy
Computer Science Department
Stanford University
Stanford, CA 94305
Tom Costello
Computer Science Department
Stanford University
Stanford, CA 94305

Abstract:

A theory is elaboration tolerant to the extent that new information can be incorporated with only simple changes. The simplest change is conjoining new information, and only conjunctive changes are considered in this paper. In general adding information to a theory should often change, rather than just enlarge, its consequences, and this requires that some of the reasoning be non-monotonic.

Our theories are narratives--accounts of sets of events, not necessarily given as sequences. A narrative is elaboration tolerant to the extent that new events, or more detail about existing events, can be added by just adding more sentences.

We propose a new version of the situation calculus which allows information to be added easily. In particular, events concurrent with already described events can be introduced without modifying the existing descriptions, and more detail of events can be added. A major benefit is that if two narratives do not interact, then they can be consistently conjoined.





John McCarthy
Thu Jul 8 18:10:07 PDT 1999