A Logic of Arbitrary and Indefinite Objects, LA, has been developed as the logic for knowledge representation and rea- soning systems designed to support natural language under- standing and generation, and commonsense reasoning. The motivations for the design ofLA are given, along with an in- formal introduction to the theory of arbitrary and indefinite objects, and to LA itself. LA is then formally defined by presenting its syntax, proof theory, and semantics, which are given via a translation scheme betweenLA and the standard classical First-Order Predicate Logic. Soundness is proved. The completeness theorem forLA is stated, and its proof is sketched.LA is being implemented as the logic of SNePS 3, the latest member of the SNePS family of Knowledge Repre- sentation and Reasoning systems.
['Stuart C. Shapiro']
A Logic of Arbitrary and Indefinite Objects