About the Author

Patrick Henry Winston (1943– 2019) was Ford Professor of Artificial Intelligence and Computer Science at MIT. Sarah A. Shellard is an editorial assistant at the Artificial Intelligence Laboratory. Daniel G. Bobrow is a Research Fellow in the Intelligent Systems Laboratory, Xerox Palo Alto Research Center, editor-in-chief of the Journal of Artificial Intelligence, and Chair of the Governing Board of the Cognitive Science Society. Michael Brady is Senior Research Scientist at MIT's Artifical Intelligence Laboratory.