Textbook of AI

1931–, Cognitive psychologist, AI researcher

Also known as: M. Ross Quillian

M. Ross Quillian was an American cognitive psychologist whose 1968 paper Semantic Memory (in Marvin Minsky's edited volume Semantic Information Processing) introduced the semantic network as a model of human knowledge representation. In a semantic network, concepts are nodes and relations are labelled edges; reasoning proceeds by spreading activation from a query node along edges to retrieve related concepts.

Quillian's work was the conceptual ancestor of every subsequent semantic-network knowledge representation in AI (KL-ONE, conceptual dependency, Description Logics, RDF and OWL of the Semantic Web), and of associative-memory models in cognitive psychology (Anderson and Bower, Collins and Loftus). The notion of spreading activation has been quietly influential in modern neural network research, where attention mechanisms and graph neural networks operationalise its core insight.