CONCEPTUAL GRAPH PROGRAMS AND THEIR DECLARATIVE SEMANTICS

Conceptual graph formalism is a knowledge representation language in A l based on a graphical form of logic. Although logic is the basis of t he conceptual graph theory, there is a strongly felt absence of a form al treatment of conceptual graphs as a logic programming language. In this paper, we develop the notion of a conceptual graph program as a k ind of graph-based order-sorted logic program. First, we define the sy ntax of the conceptual graph program by specifying its major syntactic elements. Then, we develop a kind of model theoretic semantics and fi xpoint semantics of the conceptual graph program. Finally, we show tha t the two types of semantics coincide for the conceptual graph program s.