The Architecture of Complexity

Author: Herbert A. Simon
Date: Read April 26, 1962
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Herbert A. Simon’s essay on complexity is the most cited paper in Hierarchy Theory. Herbert is a psychologist who is most noted for his work on decision theory and on organization theory. He is one of the founding figures in artificial intelligence, a winner of the Turing Award, a recipient of the Nobel Prize in Economics and a co-founder of the School of Computer Science at Carnegie Mellon University.

The central theme of the essay is that complexity frequently takes the form of hierarchy and that hierarchic systems have some common properties that are independent of their specific context. He claims that the hierarchic nature of complex systems enables us to decompose the systems into understandable and describable parts and “see” them. “If there are important systems in the world that are complex without being hierarchic, they may to a considerable extent escape our observation and our understanding.”