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Mie Augier Stanford University James G. March Stanford University Remembering Herbert A. Simon (1916–2001) Herbert A. Simon died on February 9, 2001, at the age of 84. At the time of his death, he was the Richard King Mellon University Professor at Carnegie-Mellon University, an institution that he had graced for 52 years. During his long career, he produced scholarly publications at an annual rate that was substantially greater than the lifetime rate of the vast majority of his colleagues. Simon’s first published article appeared in 1937. His official vita lists more than 900 publications in the ensuing 64 years, excluding many reprintings and translations. It is an extraordinary record, and simply recounting the numbers significantly underestimates Simon’s influence. In a narrow sense, only a very small fraction of Simon’s productivity could be described as stemming from research in public administration. But in a broader sense, many of the ideas and visions that stayed with him throughout his career were first formulated within the framework of public administration. Simon’s link to public administration is threefold: First, he started there. His early academic appointments and most of his early research were in public administration. He coauthored a textbook in public administration. Second, his impact on the field was exceptional. Almost from the beginning, he was an intellectual force. Third, he never left the field conceptually. Throughout his career, he maintained a focus on a central concern of public administration—how do limited (but reasoned) human beings, individually and in social organizations, solve problems, and how might they do so more effectively? Simon influenced many disciplines, but he was, first of all, a political scientist and a student of public administration. His writings persistently reflect a perspective drawn from his early interest in administrative decision making and public administration. This history is often overlooked, but it is obvious to anyone who reviews the entire Simon œuvre. For example, the concept of bounded rationality, which became a vital platform for much of his subsequent work in artificial intelligence (Newell 1989), emerged within the context of early work in pub396 Public Administration Review • July/August 2001, Vol. 61, No. 4 lic administration, organization theory, and economics (Simon 1989). More generally, though Simon’s interest in human problem solving led to pioneering work in disciplines that are seemingly far removed from public administration, he retained a perspective familiar to that field—a commitment not only to understanding human behavior, but also to reforming human practices and institutions. He was a proper missionary. The Beginning: Young Jesus in the Temple Herbert Simon was born in 1916 in Milwaukee, Wisconsin, and educated in political science at the University of Chicago. According to his autobiography, he chose to go to Chicago because it had an intense and strong intellectual atmosphere that suited him well. Unlike some other universities, Chicago had abandoned its heavy investment in intercollegiate athletics—a change that also suited Simon well. According to Simon, he had intended to major in economics until he learned that in order to do so, he would have to take a course in accounting. He switched to a major in political science (Simon 1991, 39) and gravitated toward research in public administration. Simon attended the University of Chicago during the Great Depression of the 1930s. It was a time of political and economic unrest, and he saw himself, as well as other students at the university, as “intensely political animals” (1991, 119). In Simon’s case, however, these political instincts were directed less into an enthusiasm for mass popular movements than into an administrative/organizational/ planning conception of the requirements of democracy. The Mie Augier is a post-doctoral fellow at Stanford University. Her research interests include behavioral economics, organization theory and organizational economics, and the history of economic thought. Email: [email protected] stanford.edu. James G. March is a professor emeritus at Stanford University. He has four children, six grandchildren, and three step-grandchildren. He also does research and writing on decision making, learning, risk taking, and the pursuit of intelligence in organizations. Email: [email protected] political science department at Chicago in the 1930s included Charles Merriam, Harold Lasswell, and Quincy Wright. That “Chicago School” was united by a general belief that rational coordination (by large organizations, public and private) is necessary for an effective democracy, and it is possible to apply methods of rational planning to the allocation of public resources. They wrestled with the problem of reconciling a scientific (rational) approach to collective choice with democracy and human values. Simon was shaped significantly by the political science environment at Chicago in the 1930s and by the projects he undertook as a young student. In 1935, he wrote a term paper on municipal government, examining the relations between institutions of city government and school boards, and another on cooperation between city governments and school districts. To pursue questions of this sort, Simon enrolled in a class taught by Clarence Ridley, “Measuring Municipal Governments.” He wrote a paper for the class, drawing ideas from economics, which led Ridley to invite Simon to participate as a research assistant in a project for the International City Manager’s Association (Simon 1991, 64). The first significant output of this study of the prosaics of city government was a series of papers written with Ridley. The papers were published in the journal Public Management and culminated in their book Measuring Municipal Activities (Ridley and Simon 1938). Simon’s work on city management was linked to the municipal reform movement. Many members of the Chicago political science environment were involved in advocating and refining the city manager form of local government. Charles Merriam, for example, had brought the International City Manager’s Association (where Simon worked as a graduate student) and the Public Administration Clearing House to Chicago. Clarence Ridley had served as a city manager for several local communities, and he argued that professional management was an important instrument for improving the efficiency of local governments (1991, 70). From Ridley, Simon learned that effective organizations can be powerful tools for achieving societal goals; he later used this as inspiration for arguing that organizations can serve as aids of human rationality and thereby improve the achievement of human goals (Simon 1947). He was to become a steady critic of pure rationality as a description of human behavior, but he never wavered from a goal of improving human rationality. March (1978b, 858) described him as “an unrepentant knight of the enlightenment.” The International City Manager’s Association provided Simon with what he later described as a “marvelous school in administration” (1991, 70), and he went on to serve as an assistant editor to the journal Public Management and the Municipal Year Book. In the course of working on the statistical sections of the yearbook, Simon first encoun- tered IBM punch-card equipment. Although counter-sorters were a relatively long step from digital computers, this experience was the beginning of his enduring fascination with digital computers, a fascination that would later become crucial for his work (McCorduck 1979; Simon 1991). As Simon studied city management, however, he became dissatisfied with public administration as a field and particularly with administrative theory. He thought the field lacked the measurement techniques and concepts necessary to develop a useful theory. At the outset, he focused on problems of measuring output, then (as now) the New Public Management. Demands about honest and efficient municipal government, Ridley and Simon argued, implied a need for standards of measurement (Ridley and Simon 1938). They called for the application of statistical knowledge in government organizations. Their study of municipal activities dealt with both historical and theoretical approaches to government, but their main emphasis was supremely pragmatic. They discussed practical tools for the management of such familiar things as fire protection, police, and education. Theoretical ideas about administration were seen as important, but as securing legitimization from their acceptance and utilization by practical administrators and decision makers (Ridley and Simon 1938, 2). The idea that theories should be both sophisticated and empirically relevant became a consistent theme of Simon’s work (1991, 1997b). Measuring Municipal Activities was well received. Its vision of planning, rationality, and science in the service of democratic values and institutions fit the political temper of the time. It portrayed administrative science as the ally of democracy and the enemy of corruption, self-interest, and waste. City planning was seen as a necessary part of democracy, setting the standards and goals for agencies in local government. Planning was seen as a vital part of democratic governance and an opportunity to integrate the desires of the people into a rational program for the community. It was a time of great hope for rationality and planning in democracy, and Ridley and Simon’s report established Simon as a promising student of city management. In his autobiography, he reports that on this road to a career, he felt like “the young Jesus in the Temple” (1991, 65), a characterization that may have exaggerated both the sacredness of Ridley and Simon’s text and his own position. But it was a heady time for a young scholar only 22 years old, and there is no question that Simon was identified as a “comer.” The Early Works: The Rebel and the Kernel As a result of his early recognition, Simon was invited to join the University of California’s Bureau of Public Tribute to Herbert A. Simon 397 Administration to study local government. He arrived in California in the fall of 1939 and began his assignment by directing a study of the administration of state relief programs. In Simon’s mind, the study was intended to demonstrate how quantitative empirical research could contribute to understanding and improving municipal government problems (1991, 82). In the course of this work, he studied the economics literature on taxation, and the conclusions from the study were published in a leading economics journal, Quarterly Journal of Economics (Simon 1943). In retrospect much later, Simon argued that his conclusions in this first publication in economics could be interpreted as questioning some aspects of the assumption of rationality found in conventional economic theory (Simon 1991, 83). Simon’s fame within public administration, however, depended neither on the Ridley and Simon report nor on his Quarterly Journal of Economics piece, but rather on his writings in the 1940s and 1950s, particularly Administrative Behavior, Public Administration (with Smithburg and Thompson), Organizations (with March), and the associated journal articles. He was determined to reform public administration, carrying forward the spirit of his mentors from Chicago but going to the heart of administrative theory as it was then perceived. The first working title of Administrative Behavior, developed from his dissertation, was “The Logical Structure of an Administrative Science.” Simon made a frontal assault on received doctrine, criticizing existing theories and principles of administration as being worse than useless as guides to practical action because of their vagueness and contradictions. He pointed out, for example, that the dictum that one should minimize span of control is not consistent (in a hierarchy) with the dictum that one should minimize the number of levels in an organization. Such contradictions led Simon to describe the principles of administration as “proverbs” and to consign them to an intellectual purgatory. This attack did not immediately impress everyone in the field, nor was it immune to criticism over the years (see Waldo 1952; Simon, Drucker, and Waldo 1952). However, it became standard reading for courses on public administration and a rallying call for young students who sought to create a new vision of public administration, one embedded in research on human behavior and organizations. Simon’s critique of administrative theory became the one part of his work that became most imprinted on the field of public administration. That critique played, however, only a minor role in his reputation outside public administration, and it did not figure prominently in Simon’s subsequent interpretation of Administrative Behavior. On the contrary, the vital step taken in the book, as he saw it, was the identification of decision making as the ultimate keystone for the reconstruction of administrative theory. In Simon’s view, Ad398 Public Administration Review • July/August 2001, Vol. 61, No. 4 ministrative Behavior was the first place he had systematically examined the importance of limits to human rationality. For him, the book contained both the foundation and “much of the superstructure of the theory of bounded rationality that has been my lodestar for nearly fifty years” (Simon 1991, 86). Decision making, as it is portrayed in Administrative Behavior, is purposeful, but not rational. Rational decision making would involve a comprehensive specification of all possible outcomes, conditional on possible actions, in order to choose the single, alternative action that is best— but such comprehensive calculation is not possible. In this way, Simon introduced his well-known thoughts on limits to human rationality. Administrative theory, he argued, must be concerned with the limits of rationality, and the manner in which organization affects those limits. Organizations make it possible to make decisions because they constrain the set of alternatives to be considered and the considerations that can be treated as relevant. Organizations can be improved by improving the ways in which those limits are defined and imposed. In the same book, Simon began to formulate his ideas about the relation between “facts” and “values” and the hierarchical organization of means and ends. To Simon, all decisions, administrative and otherwise, involve elements of both facts and values, creating challenges to articulating a proper relationship between administrative authority and democratic principles. He never wavered from this concern, though his work after leaving public administration tended to subordinate politics and values to problem solving, where objectives and values were not conspicuously problematic. Ideas about the hierarchical organization of problem solving, first hinted at in Administrative Behavior, became much more central to his later work. He recognized the attraction of the idea of a hierarchy of decisions, where one stage in the hierarchy influences the next step, and so on, and purposeful action is achieved through a hierarchical chain of decisions guided by general goals and objectives (1947, 4–5). To link the idea of hierarchical control and subordination with the reality of conflict of interest, he took from Chester Barnard the idea of inducements and contributions—the notion that individuals in a hierarchy might be induced to accept the authority of superiors through some kind of compensatory inducement for their contributions. Simon would later apply this theme to the study of employment relations in a well-known article (Simon 1951). The theme of hierarchy became very important to Simon’s later work on near-decomposability, causality, and complex systems (1952, 1953, 1969). It also influenced his work in computer science, where he saw the underlying structure of computational memory as hierarchical (1977), and in problem solving, where he saw problems as generally decomposable into hierarchical structures (Simon 1989). In Simon’s visions for a science of administration, the fact that decisions are hierarchically ordered led him to focus on hierarchically organized decision processes and the organization of decision making and problem solving into hierarchies of ends and means. In his visions for artificial intelligence, the general problem solver (Newell, Shaw, and Simon 1962) was an implementation of a means– ends analysis as a computational tool for problem solving. Administrative Behavior was first published in 1947. The thesis version was defended by Simon when he returned to Chicago in 1942 as a faculty member at the Illinois Institute of Technology. Simon taught topics in political science, such as American political institutions and ideas, constitutional law and administrative aspects of planning (1991, 94); in 1946, after the end of the World War II, Simon became the chairman of the Department of Political and Social Sciences. The department was joined by Donald Smithburg and Victor Thompson, and the three of them extended the framework of Administrative Behavior into a textbook on public administration. Their book, Public Administration, was published in 1950. Like Administrative Behavior, Public Administration became a standard text for the “young Turks” of public administration. Like Administrative Behavior, it was based partly on Simon’s dissatisfaction with existing texts on that subject. Public Administration aimed at applying sociological and psychological theory to problems of administration in the public sector. It addressed many of the problems discussed in Administrative Behavior, but it embedded the abstract discussion of the earlier book in considerably greater institutional and practical detail. Simon and his coauthors provided detailed discussions of real-world behavior of real-world organizations, covering issues such as the origins of government organization, organizational behavior, group values and authority, problems of evaluating administrative efficiency, and administrative responsibility. The Later Works: The Continuity and the Glory Though a paper written shortly before his death addresses public administration and its relations to organizations and markets (Simon 2000), most of Simon’s papers after Public Administration appeared not in public administration journals, but in major journals in every social science discipline except anthropology. Although almost every field claims Simon as their Nobel Prize winner, public administration must share him with much of social science (Feigenbaum 1989). His best-known books after 1950 included Organizations (1958, with James G. March), Sciences of the Artificial (1969), Human Problem Solving (1972, with Allen Newell), Models of Bounded Rationality (three volumes, 1982 and 1997a), and his autobiography, Models of My Life (1991). Through these books and his hundreds of articles, Simon made significant contributions to economics, psychology, political science, sociology, administrative theory, public administration, organization theory, computer science, cognitive science, and philosophy. As a result of these extraordinary contributions, Simon received innumerable prestigious awards, such as the A.M. Turing Award (1975), the Nobel Prize in Economics (1978), and the National Medal of Science (1986). He received the James Madison Award from the American Political Science Association, the Dwight Waldo Award from the American Society for Public Administration, and the Gold Medal Award for Life Achievement in Psychological Science from the American Psychological Association. He was a Fellow of the Econometric Society and was elected to the American Philosophical Society, the National Academy of Sciences, and the American Academy of Arts and Sciences, as well as numerous foreign honorary societies. He was awarded honorary doctorates by Harvard University, Columbia University, Yale University, and the University of Chicago, among many others in the United States and abroad. He was pre-eminently a scholar, but he was also actively involved in giving advice on public policy, having served on the Committee on Science and Public Policy and the President’s Science Advisory Committee. Simon was precociously inattentive to disciplinary or field boundaries. In his autobiography, Simon identified his three main teachers outside the political science department at the University of Chicago as Henry Schultz, Nicholas Rashevsky, and Rudolph Carnap. He thought Schultz’s book, The Theory and Measurement of Demand, provided an example of the possibilities of applying mathematics to the study of human behavior (1991, 51). Schultz also taught him to appreciate the philosophical problems involved in measurement and model making in economics, particularly those associated with the identification problem. He was also inspired by the use of mathematics in the social sciences pioneered by Rashevsky, a biophysicist. They shared both an interest in applying sophisticated mathematics to empirical problems and a conviction about the centrality of organization in social and biological life. Finally, he gained from Carnap, a central figure in the Vienna Circle, both a philosophical foundation (logical positivism) upon which to build his epistemology and a framework for understanding the nature of formal logic and how it could be used in social science. Simon’s subsequent work on causality and purpose combined Carnap’s empiricism with a firm (non-empiricist) belief that theories represented important aspects of reality. Tribute to Herbert A. Simon 399 These early excursions out of political science were elaborated and given a more profoundly economic twist by his exposure to the Cowles Commission at the University of Chicago (Simon 1991). After World War II, the Cowles Commission drew together an exceptional group of mathematical economists doing pioneering research in econometrics, linear and dynamic programming and decision theory, among other things (Christ 1994). The economists connected with the Cowles Commission included such wellknown names as Kenneth Arrow, Jacob Marshak, Tjalling Koopmans, and Gerard Debreu. During the last years of Simon’s stay at Chicago, he was persuaded by his friend William W. Cooper to begin attending the Cowles Commission seminars. These seminars placed him in contact with a group of economists who would become the leaders of modern American economics and lifelong friends. As a group, the Cowles Commission economists of the 1940s and 1950s were committed to seeing human decision making in terms of unconstrained rationality, but Simon felt at home with their emphasis on clarity and mathematics. Indeed, Simon’s activities at the Cowles Commission “almost converted [him] into a full time economist” (Simon 1991). The major stumbling block to such a conversion was the conception of decision making held by the economists at Cowles. Simon had little faith in the idea that decision makers make rational choices by maximizing utility. He thought it did not describe human behavior very well, and he wanted to outline a more behavioral model for understanding decision making. Despite his attraction to economics, and subsequently to other disciplines, Simon kept returning to the central questions of his public administration research: He asked how ordinary humans and ordinary organizations make intelligent decisions when people are only boundedly rational. This question was central to Simon’s work in economics, computer science, psychology, and organizations. As he noted (1989, 378), “A problem I found in 1935 has lasted [with] me. I never had to find another.” Kernels of the answers that he pursued can be found in his public administration work, but the earliest clear exposition was provided in two very influential articles in the 1950s (Simon 1955, 1956), one published in a major economics journal, the other in a major psychology journal. These two papers argued that the cognitive limitations of human decision makers were important constraints on rational action, and they developed the idea of “satisficing,” the notion that decision makers seek alternatives that are “good enough” rather than “the best.” March (1978a) summarized Simon’s argument: It started from the proposition that all intendedly rational behavior is behavior within constraints. Simon added the idea that the list of technical con- 400 Public Administration Review • July/August 2001, Vol. 61, No. 4 straints on choice should include some properties of human beings as processors of information and as problem solvers. The limitations were limitations of computational capability, the organization and utilization of memory, and the like. He suggested that human beings develop decision procedures that are sensible, given the constraints, even though they might not be sensible if the constraints were removed. As a short-hand label for such procedures, he coined the term “satisficing.” (590). Over the subsequent years of his career, Simon continued to expand and elaborate the idea that human agents, although intending to make rational decisions, were constrained by their limited ability to process information. The core ideas of bounded rationality were published after Simon had moved from Chicago to the historically important and very interdisciplinary environment of the Graduate School of Industrial Administration at Carnegie Institute of Technology (later Carnegie-Mellon University). Persuaded (again) by Bill Cooper to come to Carnegie Institute of Technology, Simon joined the emerging graduate school in 1949 as both the head of the Department of Industrial Administration and as associate dean of the new school. Carnegie became an important chapter in Simon’s life and he stayed there, despite the enticements of places such as Chicago, MIT, and Harvard. During the 1950s and 1960s, this small school gathered together a truly unique collection of scholars and created an environment that, during a brief two decades, produced four Nobel laureates and 10 members of the National Academy of Sciences. At GSIA, Simon found (and created) an environment that could accommodate and elaborate the broad and interdisciplinary interests he had developed during his student years at the University of Chicago. With his colleagues there, he set out to build an interdisciplinary, behavioral social science relevant for many disciplines (Augier 2001). When Simon came to Carnegie in 1949, he believed that research in organizational psychology and sociology was necessary to understand human decision making. He also had a strong interest in mathematics, and he wanted to apply these interests to a major study of organizations. He set out to combine insights from social psychology, organization theory, and sociology with knowledge from economics and mathematical tools such as linear programming, operations research, and formal modeling to the understanding of decision making in organizations. In 1958, he published a book (Organizations, written with March) in that spirit, which became widely cited throughout the social sciences. Simon also worked with Jack Muth, Charles Holt, and Franco Modigliani on dynamic programming techniques. Over time, he began to focus more intensively on human problem solving, particularly with Allen Newell. Through their collaboration, which began in 1954, they produced the first artifi- cial intelligence program, the Logic Theorist. Simon’s collaboration with Newell culminated in their joint work, published in 1972 as Human Problem Solving, a book that became as influential in cognitive science and artificial intelligence as Simon’s earlier works have been in economics and organizations. In the midst of all this, Simon became increasingly interested in the potential of the digital computer. Although he had been interested in computers before, he first got a chance to work seriously with them at the RAND Corporation and quickly recognized their significance. Simon saw computers as an instrument for understanding and improving human decision making. Computers could play chess, solve problems, even think (McCorduck 1979). Using this premise, he made major contributions to artificial intelligence and computer science. For instance, the development of expert systems (specialized computer programs that can make expert judgments in a particular field) such as EPAM (designed with Edward Feigenbaum), a simulation study of human behavior and learning (Feigenbaum and Simon 1963) are products of this insight. While it was basically a learning system, EPAM showed expert capabilities by recognizing and sorting stimuli and producing responses from its data memory. This research has been influential for subsequent work on expert systems (see Feigenbaum, McCorduck, and Nii 1988; Feigenbaum, 1989). Simon also worked on other AI programs such as BACON and DALTON (Langley et al. 1987), which try to extract laws from regularities in empirical data (Simon 1991, 371–2), and KEKADA (Kulkarni and Simon 1988), a program that designs sequences of experiments and adapts each new experiment to the findings of the previous ones. In this work, Simon returned to the spirit of his earliest efforts to reform practice, now focusing not on attacking inefficiency in city management but on attacking inefficiency in human problem solving, including the work of scientists. For Simon, these programs represented a continuation of his research in bounded rationality. “It is not a theory of global rationality but one of human limited computation in the face of complexity,” he wrote (1991, 386). In one of his more magisterially poetic pronouncements, he said of his work on scientific discovery: “[I]t views discovery as problem solving; problem solving as heuristic search through a maze; and heuristic problem solving as the only fit activity for a creature of bounded rationality’ (386). The Ending: The Sorrows and the Pride Any brief discussion of this major figure in twentiethcentury social science omits many of his important contributions—contributions to modeling group behavior, to theories of the size distribution of firms, to the analysis of aggregation problems, and to a host of other things that attracted his attention during his career. He wanted to create a broad, interdisciplinary, behavioral social science. In order to do that, he became a political scientist, a sociologist, an economist, a psychologist, and a computer scientist, establishing himself in each field as a leader. He was a giant, and several disciplines claim him. It may, however, be legitimate for public administration to observe that the foundations of his work were laid in his early participation in the pursuit of a science of administration (Ridley and Simon 1938; Simon 1947; Simon, Smithburg, and Thompson 1950). His research and writings in public administration set the style and agenda for his subsequent career in four major ways. • First, his work in public administration taught him to be driven by ideas and practical problems. Throughout his life, he was convinced that science must deal with concrete and practical problems to be theoretically fruitful and empirically relevant (1997b). His interest in interdisciplinary work stemmed not from an abstract belief in the unity of knowledge, but from the pragmatic necessity of many forms of knowledge to deal with real problems. • Second, from working in public administration he drew the conclusion that good theory comes out of engaging practical problems, that working on serious problems from the real world is a major source of theoretical progress. • Third, his training in public administration convinced him not only of the difficulties of acting rationally in life, but also of the necessity of doing so. In his later career, he would return to a concern reflected in his early writings—a concern for improving the intelligence of human decision. • Fourth, it was in the context of public administration that he first conceived the focus on decision making and the basic ideas of bounded rationality and the hierarchical organization of problems that structured much of his later thought. Over the years, these ideas were enriched and modified, but their core notions date from Simon’s earliest work in public administration. Simon’s career began with an inquiry into the practical concerns of city management and extended into the fundamentals of public administration, economics, organization theory, psychology, and artificial intelligence. In all of these fields, his intellectual legacy constitutes a remarkable basis for understanding human behavior, and, with his death, each of his disciplines has suffered a major loss. In the last year of his life, he violated a personal rule against travel and journeyed to Washington to deliver the John Gaus Lecture, perhaps because he, like the rest of us, felt it was time for him to come home. In a deep sense, he was a child of public administration, and it is the parents who suffer the greatest anguish—and take the greatest pride. Tribute to Herbert A. Simon 401 References Augier, Mie. 2001. Sublime Simon: The Consistent Vision of Economic Psychology’s Nobel Laureate. Journal of Economic Psychology, forthcoming. Christ, Carl. 1994. The Cowles Commission’s Contributions to Econometrics at Chicago, 1939–55. Journal of Economic Literature 32: 30–59. Feigenbaum, Edward. 1989. What Hath Simon Wrought? In Complex Information Processing: The Impact of Herbert A. Simon, edited by D. Klahr and K. Kotovsky. Hillsdale, NJ: Lawrence Erlbaum Associates Publishers. Feigenbaum, Edward, and Herbert A. Simon. 1963. Brief Notes on the EPAM Theory of Verbal Learning. In Verbal Behavior and Learning, edited by C.N. Cofer and B.S. Musgrave. New York: McGraw-Hill. Feigenbaum, Edward, Pamela McCorduck, and H.P. Nii. 1988. The Rise of the Expert Company. New York: Times Books. Holt, Charles C., Franco Modigliani, John F. Muth, and Herbert A. Simon. 1960. Planning, Production, Inventories, and Work Force. Englewood Cliffs, NJ: Prentice-Hall. Kulkarni, D., and Herbert A. Simon. 1988. The Processes of Scientific Discovery: The Strategy of Experimentation. Cognitive Science 12: 139–75. Langley, P., Herbert A. Simon, G. Bradshaw, and J. Zytkow. 1987. Scientific Discovery: Computational Explorations of the Creative Processes. Cambridge, MA: MIT Press. McCorduck, Pamela. 1979. Machines Who Think. San Francisco, CA: Freeman. March, James G. 1978a. Bounded Rationality, Ambiguity, and the Engineering of Choice. Bell Journal of Economics 9: 587– 608. ———. 1978b. The 1978 Nobel Prize in Economics. Science, November 24, 858–61. March, James G., and Herbert A. Simon. 1958. Organizations. New York: Wiley. Newell, Allen. 1989. Putting It All Together. In Complex Information Processing: The Impact of Herbert A. Simon, edited by D. Klahr and K. Kotovsky. Hillsdale, NJ: Lawrence Erlbaum Associates Publishers. Newell, Allen, and Herbert A. Simon. 1972. Human Problem Solving. Englewood Cliffs, NJ: Prentice-Hall. Newell, Allen, C. Shaw, and Herbert A. Simon. 1962. The Process of Creative Thinking. In Contemporary Approaches to Creative Thinking, edited by H.E. Grubert and W. Wertheimer. New York: Atherton Press. 402 Public Administration Review • July/August 2001, Vol. 61, No. 4 Ridley, Clarence E., and Herbert A. Simon. 1938. Measuring Municipal Activities. Chicago: International City Manager’s Association. Schultz, Henry. 1938. The Theory of Measurement and Demand. Chicago: University of Chicago Press. Simon, Herbert A. 1943. The Incidence of a Tax on Urban Real Property. Quarterly Journal of Economics 57: 398–420. ———. 1947. Administrative Behavior. New York: Free Press. ———. 1951. A Formal Theory of the Employment Relationship. Econometrica 19: 293–305. ———. 1952. On the Definition of the Causal Relation. The Journal of Philosophy 49: 517–28. ———. 1953. Causal Ordering and Identifiability. In Studies in Econometric Method, edited by W.C. Hood and J.C. Koopmans. New York: Wiley. ———. 1955. A Behavioral Model of Rational Choice. Quarterly Journal of Economics 69: 99–118. ———. 1956. Rational Choice and the Structure of the Environment. Psychological Review 63: 129–38. ———. 1969. The Sciences of the Artificial. Cambridge, MA: MIT Press. ———. 1977. Models of Discovery. Dordrecht, Holland: Reidel. ———. 1982. Models of Bounded Rationality. Vol. 1, 2. Cambridge, MA: MIT Press. ———. 1989. The Scientist as Problem Solver. In Complex Information Processing: The Impact of Herbert A. Simon, edited by D. Klahr and K. Kotovsky. Hillsdale, NJ: Lawrence Erlbaum Associates Publishers. ———. 1991. Models of My Life. Cambridge, MA: MIT Press. ———. 1997a. Models of Bounded Rationality. Vol. 3. Cambridge, MA: MIT Press. ———. 1997b. An Empirically Based Microeconomics. Cambridge, UK: Cambridge University Press. ———. 2000. Public Administration in Today’s World of Organizations and Markets. Political Science and Politics 33(4): 749–56. Simon, Herbert A., Peter F. Drucker, and Dwight Waldo. 1952. Development of Theory of Democratic Administration: Replies and Comments. American Political Science Review 46(2): 494–503. Simon, Herbert A., Donald W. Smithburg, and Victor A. Thompson. 1950. Public Administration. New York: Alfred A. Knopf. Waldo, Dwight. 1952. The Development of Theory of Democratic Administration. American Political Science Review 46(1): 81–103.