Herbert A. Simon (1916-2001) was one of the most influential social scientists of the 20th century, making foundational contributions to artificial intelligence, cognitive psychology, economics, organizational theory, and philosophy of science. He won the Nobel Prize in Economics in 1978 for his theory of bounded rationality, and the Turing Award in 1975 (with Allen Newell) for contributions to artificial intelligence. His work consistently addressed a central question: how do humans think, decide, and solve problems given their limited cognitive resources?
Bounded Rationality
Simon's concept of bounded rationality challenged the economic assumption of perfect rational agents. Human decision-makers have limited information, limited computational capacity, and limited time. Rather than optimizing (finding the best possible option), people satisfice — they search through options until they find one that meets their aspiration level ("good enough"). This is not irrational but is adaptive given cognitive constraints. Bounded rationality has influenced economics, organizational theory, AI, and the heuristics and biases research of Kahneman and Tversky.
With Allen Newell, Simon developed the information processing theory of human problem solving. Their General Problem Solver (1957) was one of the first AI programs and also a theory of human thinking: problems are solved by searching through a problem space using heuristics like means-end analysis. Their verbal protocol analysis method — having people think aloud while solving problems — became a standard research methodology. Their work on expert chess players showed that expertise depends on pattern recognition from stored chunks rather than superior search, with grandmasters storing approximately 50,000 chess patterns in long-term memory.