Kenneth Joseph Arrow (August 23, 1921 – February 21, 2017) was an American economist, mathematician and political theorist. He received the John Bates Clark Medal in 1957, and the Nobel Memorial Prize in Economic Sciences in 1972, along with John Hicks. In economics, Arrow was a major figure in postwar neoclassical economic theory. Four of his students (Roger Myerson, Eric Maskin, John Harsanyi, and Michael Spence) went on to become Nobel laureates themselves. His contributions to social choice theory, notably his "impossibility theorem", and his work on general equilibrium analysis are significant. His work in many other areas of economics, including endogenous growth theory and the economics of information, was also foundational.
Education and early career Arrow was born on August 23, 1921, in New York City. Arrow's mother, Lilian (Greenberg), was from Iași, Romania, and his father, Harry Arrow, was from nearby Podu Iloaiei. The family was of Romanian-Jewish descent, and very supportive of Kenneth's education. Growing up during the Great Depression, he embraced socialism in his youth. He would later move away from socialism, but his views retained a left-leaning philosophy. He graduated from Townsend Harris High School and then earned a bachelor's degree in mathematics from the City College of New York in 1940, where he was a member of Sigma Phi Epsilon. He then attended Columbia University for graduate studies, obtaining a master's degree in mathematics in June 1941. At Columbia, Arrow studied under Harold Hotelling, who influenced him to switch fields to economics. He served as a weather officer in the United States Army Air Forces from 1942 to 1946.
Academic career From 1946 to 1949, Arrow was a graduate student at Columbia University, and also worked as a research associate at the Cowles Commission. During that time he also was an assistant professor of economics at the University of Chicago and worked at the RAND Corporation in California. He left the University of Chicago to become an acting assistant professor of economics and statistics at Stanford University. In 1951, he received a PhD degree from Columbia University. He served in the government on the staff of the Council of Economic Advisers in the 1960s with Robert Solow. In 1968, he left Stanford for Harvard University, where he was appointed Professor of Economics; it was during his tenure there that he received the Nobel Prize in Economics. Arrow returned to Stanford University in 1979 and became the Joan Kenney Professor of Economics and Professor of Operations Research. He retired in 1991. As a Fulbright Distinguished Chair, in 1995 he taught economics at the University of Siena. He was also a founding member of the Pontifical Academy of Social Sciences and a member of the board at the Santa Fe Institute. At various stages in his career he was a Fellow of Churchill College, Cambridge. He was one of the founding editors of the Annual Review of Economics, which was first published in 2009. Four of his former students have gone on to become Nobel Prize winners, namely John Harsanyi, Eric Maskin, Roger Myerson, and Michael Spence. A collection of Arrow's papers is housed at the Rubenstein Library at Duke University.
Arrow's impossibility theorem
Arrow's monograph Social Choice and Individual Values derives from his 1951 PhD thesis.
If we exclude the possibility of interpersonal comparisons of utility, then the only methods of passing from individual tastes to social preferences which will be satisfactory and which will be defined for a wide range of sets of individual orderings are either imposed or dictatorial. In what he named the General Impossibility Theorem, he theorized that, unless we accept to compare the levels of utility reached by different individuals, it is impossible to formulate a social preference ordering that satisfies all of the following conditions:
Nondictatorship: The preferences of an individual should not become the group ranking without considering the preferences of others. Individual Sovereignty: each individual should be able to order the choices in any way and indicate ties Unanimity: If every individual prefers one choice to another, then the group ranking should do the same Freedom From Irrelevant Alternatives: If a choice is removed, then the others' order should not change Uniqueness of Group Rank: The method should yield the same result whenever applied to a set of preferences. The group ranking should be transitive. The theorem has implications for welfare economics and theories of justice, and for voting theory (it extends the Condorcet paradox). Following Arrow's logical framework, Amartya Sen formulated the liberal paradox which argued that given a status of "Minimal Liberty" there was no way to obtain Pareto optimality, nor to avoid the problem of social choice of neutral but unequal results.
General equilibrium theory
Work by Arrow and Gérard Debreu and simultaneous work by Lionel McKenzie offered the first rigorous proofs of the existence of a market clearing equilibrium. For this work and his other contributions, Debreu won the 1983 Nobel Prize in Economics. Arrow went on to extend the model and its analysis to include uncertainty, the stability. His contributions to the general equilibrium theory were influenced by Adam Smith's Wealth of Nations. Written in 1776, The Wealth of Nations is an examination of economic growth brought forward by the division of labor, by ensuring interdependence of individuals within society. In 1974, The American Economic Association published the paper written by Kenneth Arrow, General Economic Equilibrium: Purpose, Analytic Techniques, Collective Choice, where he states:
… excerpt ends here. Continue reading the full article.
