Simon, Herbert A.

American Professor of Computer Science and Psychology
1916–2001

Herbert A. Simon combined the study of social and behavioral science with the disciplines of mathematics, physics, and economics in a career that included a longtime focus on the science of decision-making in organizations. Of particular note is his analysis of decision-making and problem-solving, but he was also interested in artificial intelligence (AI) and the use of the computer to study intelligence and cognition, both in problem-solving, such as the discovery of theorems, and in game playing, such as chess.

Simon was born in Milwaukee, Wisconsin, on June 15, 1916. His father was an electrical engineer and his mother an accomplished pianist. He enrolled at the University of Chicago in 1933 and graduated in 1936 with a degree in political science. He received his doctorate through the University of Chicago in 1943 while heading a research group at the University of California, Berkeley, between 1939 and 1942. He taught at the Illinois Institute of Technology from 1942 to 1949, and he engaged in research with colleagues at the University of Chicago and the Cowles Commission for Research in Economics. His next professional post was at the Carnegie Institute of Technology (now Carnegie Mellon University), where he helped build the Graduate School of Industrial Administration.

Simon's career in Pittsburgh as an academic, researcher, and author spanned more than fifty years. He was well respected by colleagues and students. He believed that the approach of the "hard" sciences, such as physics and mathematics, could be applied to the behavioral sciences, both in economics and political science, his first field of study, and the behavioral sciences, primarily psychology and cognitive science.

One of Simon's earliest books, published in 1947, was Administrative Behavior. The book was an expansion of his doctoral dissertation, which began his studies of rationality. Later publications include Models of Man (1957), The Sciences of the Artificial (1969), Human Problem Solving, with Allen Newell (1972), and Models of Discovery (1977), among others. In 1991 he published an autobiography, Models of My Life.

Simon firmly believed that the computer could and should aid in the study of human cognition and, ultimately, that what the computer could do in terms of cognition was "think." He considered the computer to be a laboratory for epistemology, the study of knowledge or truth, as well as a tool for investigating the human mind. In 1954 Simon began using computers to model problem-solving.

Simon developed what he termed the theory of "satisficing," that is, the making of decisions on the basis of a satisfactory rather than optimal (absolute best) solution. This is a technique familiar to anyone who has done even such a routine task as develop a schedule of college courses for a term. One must make choices that meet certain requirements for one's degree, balancing other factors such as personal preferences for times of classes, subjects one is interested in, distance to and from classes, and cost to create a satisfactory, albeit possibly imperfect, schedule.

Simon studied "bounded rationality," the theory of making rational decisions under constraints such as a lack of knowledge, computational difficulty, and personal and social circumstances. The decisions are rational, but not in the sense of an all-knowing, infallible optimizer. This leads to finding acceptable, but not necessarily optimal, solutions to problems.

From 1966 until his death on February 9, 2001, Simon was Richard King Mellon University Professor of Computer Science and Psychology. He won the Nobel Prize in Economics in 1978 for "pioneering research into the decision-making process within economic organizations." He was awarded the National Medal of Science in 1986 and the A.M. Turing Award by the Association of Computing Machinery (ACM) in 1975, with Allen Newell (1927–1992). He collaborated with Newell and Clifford Shaw to write a computer program, the Logic Theorist, or the Logic Theorem Machine, designed to find logical proofs. Together, the three also collaborated on a software program designed to play chess as a human, not an expert. He was involved in several computer projects to study human cognition and form models of human learning, problem solving, and "thinking" using computer programs.