High Quality Content by WIKIPEDIA articles! John Florian Sowa is the computer scientist who invented conceptual graphs, a graphic notation for logic and natural language, based on the structures in semantic networks and on the existential graphs of Charles S. Peirce. He is currently developing high-level "ontologies" for artificial intelligence and automated natural language understanding. International conferences on conceptual graphs have been held for over a decade since before 1992. Sowa combines ideas from numerous disciplines and eras modern and ancient, for example, applying ideas from Aristotle, the medieval Scholastics to Alfred North Whitehead and including database schema theory, and incorporating the model of analogy of Islamic scholar Ibn Taymiyyah in his works.