Conceptual graph

John F. Sowa's conceptual graphs (CGs) are a system of logic based on the existential graphs of Charles Sanders Peirce and the semantic networks of artificial intelligence. They express meaning in a form that is logically precise, humanly readable, and computationally tractable. With their direct mapping to language, conceptual graphs serve as an intermediate language for translating computer-oriented formalisms to and from natural languages. With their graphic representation, they serve as a readable, but formal design and specification language. CGs have been implemented in a variety of projects for information retrieval, database design, expert systems, and natural language processing.

Projects and tools
A list of projects in which CGs play a key role is to follow. A page about CG tools has been created; it compares CG tools on over 160 criteria.

Related work
Together with concepts like conceptual schema, semantic network, knowledge representation, principal components analysis, Teuvo Kohonen's self-organizing maps, and Bayesian inference, conceptual graphs may eventually make it possible to implement intelligent agents for unsupervised learning.

Reference

 * Sowa, J.F. (1984), Conceptual Structures: Information Processing in Mind and Machine, Addison-Wesley, Reading, MA, 1984.

People
There is a lively worldwide conceptual graphs research community. The community usually meets at the International Conferences on Conceptual Structures (ICCS) which have been held annually in Europe, Australia, and North America since 1993. The following is a sample listing of currently active researchers on conceptual graphs:


 * Galia Angelova – Bulgaria
 * Tru Cao – Vietnam
 * Michel Chein – France
 * Dan Corbett – USA
 * Harry Delugach – USA
 * David Genest – France
 * Ollivier Haemmerle – France
 * Adil Kabbaj – Morocco
 * Pavel Kocura – UK
 * Robert Levinson – USA
 * Philippe Martin – Australia
 * Guy Mineau – Canada


 * Aldo de Moor – Belgium
 * Bernard Moulin – Canada
 * Marie-Laure Mugnier – France
 * Engelbert Mephu Nguifo
 * Ulrik Petersen – Denmark
 * Heather Pfeiffer – USA
 * Simon Polovina – UK
 * Henrik Schaerfe – Denmark
 * Robert Spillers
 * John Sowa – USA
 * Albena Strupchanska – Bulgaria
 * Gerd Stumme

Resources

 * Conceptual Structures Home Page
 * Conceptual Graphs Home Page
 * John F. Sowa
 * University of Aalborg Online Course

Konzeptgraph Graphe conceptuel