The Extensional Semantics of the Conceptual Graph Formalism

Abstract

This paper gives the extensional semantics definitions associated with simple conceptual graphs (CG) under a simple paradigm closely related to relational database (RDB) theory. We believe that by providing such definitions, the implementation of a CG system using this paradigm would be greatly facilitated. Considering the nature of CGs, existentially quantified assertions, the use of a RDB at the implementation level becomes attractive for applications with huge volume of data (like with deductive databases). Furthermore, RDB theory provides years of experience, stability and on-going support of the many tools that the industry offers today. These advantages become prerequisite when choosing a technological platform for a large scale industrial project. This paper provides a formal basis for understanding the deep semantics of the CG notation, including the compositional semantics of the canonical formation operators. It also provides a simple procedure that performs model c hecking of graphs in a CG system.