"To distinguish the meaningful graphs that represent real or possible situations in the external world, certain graphs are declared to be canonical."

“John F. Sowa homepage”

“Conceptual graphs are system of logic based on the existential graphs of Charles Sanders Peirce and the semantic networks of artificial intelligence. The purpose of the system is to express meaning in a form that is logically precise, humanly readable, and computationally tractable. With their direct mapping to language, conceptual graphs can serve as an intermediate language for translating computer-oriented formalisms to and from natural languages. With their graphic representation, they can serve as a readable, but design and specification language.”

“A conceptual graph is a finite connected bipartite graph which consists of concepts and conceptual relations. Every conceptual relation has one or more arcs, each of which is linked to a concept. We define a multilevel conceptual graph to be a conceptual graph in which some of the concepts and conceptual relations arc sensitive.”

“An analysis of the concept of mind is an important philosophical issue, but the analysis cannot be reduced to programming of physiological terms... the way people think and the way computers can simulate thinking.”

“Soon, the enterprise of the information age will find itself immobilized if it does not have the ability to tap the information resources within and without its boundaries.”

“We define a semantic network as "the collection of all the relationships that concepts have to other concepts, to percepts, to procedures, and to motor mechanisms" of the knowledge.”