Systems of relational transformations: rules and realizability criterion

The paper describes and investigates basic constructions and semantics of an action description language developed to analyze transformations of relations between situation models (relational transformations). The main difference between KSL (Knowledge Specification Language) and traditional languages (STRIPS, ADL, PDDL, etc.) is the exploitation of not only traditional (STRIPS-like) rules but also their set-theoretic compositions. This greatly increases the expressiveness of a language. A clear first order logic characterization of relational transformations (without using additional constructions of a situation calculus) makes it possible to formulate and prove a natural criterion of realizability (consistency) of the system of relational transformations and, consequently, to describe and fix the logical contradictions of the given system.