Robert Merton Solow,
GCIH (; August 23, 1924 – December 21, 2023) was an American economist who received the 1987
Nobel Memorial Prize in Economic Sciences, and whose work on the theory of
economic growth
In economics, economic growth is an increase in the quantity and quality of the economic goods and Service (economics), services that a society Production (economics), produces. It can be measured as the increase in the inflation-adjusted Outp ...
culminated in the
exogenous growth model named after him.
He was
Institute Professor Emeritus
''Emeritus/Emerita'' () is an honorary title granted to someone who retires from a position of distinction, most commonly an academic faculty position, but is allowed to continue using the previous title, as in "professor emeritus".
In some c ...
of Economics at the
Massachusetts Institute of Technology
The Massachusetts Institute of Technology (MIT) is a Private university, private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of moder ...
, where he was a professor from 1949 on. He was awarded the
John Bates Clark Medal in 1961, the
Nobel Memorial Prize in Economic Sciences in 1987, and the
Presidential Medal of Freedom in 2014. Four of his PhD students,
George Akerlof,
Joseph Stiglitz,
Peter Diamond, and
William Nordhaus, later received Nobel Memorial Prizes in Economic Sciences in their own right.
Biography
Robert Solow was born in Brooklyn, New York, into a
Jewish
Jews (, , ), or the Jewish people, are an ethnoreligious group and nation, originating from the Israelites of History of ancient Israel and Judah, ancient Israel and Judah. They also traditionally adhere to Judaism. Jewish ethnicity, rel ...
family on August 23, 1924, the oldest of three children. He attended local public school and excelled academically early in life.
In September 1940, Solow went to
Harvard College
Harvard College is the undergraduate education, undergraduate college of Harvard University, a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Part of the Harvard Faculty of Arts and Scienc ...
with a scholarship at the age of 16. At Harvard, his first studies were in
sociology
Sociology is the scientific study of human society that focuses on society, human social behavior, patterns of Interpersonal ties, social relationships, social interaction, and aspects of culture associated with everyday life. The term sociol ...
and
anthropology
Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, society, societies, and linguistics, in both the present and past, including archaic humans. Social anthropology studies patterns of behav ...
as well as elementary economics.
In 1942, Solow left the university and joined the
U.S. Army. Because he was fluent in German, the Army put him on a task force whose primary purpose was to intercept, interpret, and send back German messages to base.
He served briefly in
North Africa
North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...
and
Sicily
Sicily (Italian language, Italian and ), officially the Sicilian Region (), is an island in the central Mediterranean Sea, south of the Italian Peninsula in continental Europe and is one of the 20 regions of Italy, regions of Italy. With 4. ...
, and later in Italy until he was discharged in August 1945.
Shortly after returning, he proceeded to marry his girlfriend, Barbara Lewis (died 2014), whom he had been dating for six weeks.
Solow returned to Harvard in 1945, and studied under
Wassily Leontief. As Leontief's research assistant he produced the first set of capital-coefficients for the
input–output model. Then he became interested in
statistics
Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...
and
probability
Probability is a branch of mathematics and statistics concerning events and numerical descriptions of how likely they are to occur. The probability of an event is a number between 0 and 1; the larger the probability, the more likely an e ...
models. From 1949 to 1950, he spent a fellowship year at
Columbia University
Columbia University in the City of New York, commonly referred to as Columbia University, is a Private university, private Ivy League research university in New York City. Established in 1754 as King's College on the grounds of Trinity Churc ...
to study statistics more intensively. During that year he also worked on his Ph.D. thesis, an exploratory attempt to model changes in the size distribution of wage income using interacting
Markov process
In probability theory and statistics, a Markov chain or Markov process is a stochastic process describing a sequence of possible events in which the probability of each event depends only on the state attained in the previous event. Informally, ...
es for employment-unemployment and wage rates.
In 1949, just before going off to Columbia, he was offered and accepted an assistant professorship in the
Economics Department at Massachusetts Institute of Technology. At MIT he taught courses in statistics and
econometrics
Econometrics is an application of statistical methods to economic data in order to give empirical content to economic relationships. M. Hashem Pesaran (1987). "Econometrics", '' The New Palgrave: A Dictionary of Economics'', v. 2, p. 8 p. 8 ...
. Solow's interest gradually changed to
macroeconomics
Macroeconomics is a branch of economics that deals with the performance, structure, behavior, and decision-making of an economy as a whole. This includes regional, national, and global economies. Macroeconomists study topics such as output (econ ...
. For almost 40 years, Solow and
Paul Samuelson
Paul Anthony Samuelson (May 15, 1915 – December 13, 2009) was an American economist who was the first American to win the Nobel Memorial Prize in Economic Sciences. When awarding the prize in 1970, the Swedish Royal Academies stated that he "h ...
worked together on many landmark theories:
von Neumann growth theory (1953),
theory of capital (1956),
linear programming
Linear programming (LP), also called linear optimization, is a method to achieve the best outcome (such as maximum profit or lowest cost) in a mathematical model whose requirements and objective are represented by linear function#As a polynomia ...
(1958) and the
Phillips curve (1960).
Solow also held several government positions, including senior economist for the
Council of Economic Advisers (1961–62) and member of the President's Commission on Income Maintenance (1968–70). His studies focused mainly in the fields of employment and growth policies, and the theory of capital.
In 1961 he won the American Economic Association's
John Bates Clark Award, given to the best economist under age forty. In 1979 he served as president of that association. In 1987, he won the
Nobel Prize
The Nobel Prizes ( ; ; ) are awards administered by the Nobel Foundation and granted in accordance with the principle of "for the greatest benefit to humankind". The prizes were first awarded in 1901, marking the fifth anniversary of Alfred N ...
for his analysis of economic growth
and in 1999, he received the
National Medal of Science
The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral science, behavior ...
. In 2011, he received an honorary degree in Doctor of Science from
Tufts University.
Solow was the founder of the Cournot Foundation and the Cournot Centre. After the death of his colleague
Franco Modigliani, Solow accepted an appointment as new Chairman of the I.S.E.O Institute, an Italian nonprofit cultural association which organizes international conferences and summer schools. He was a founding trustee of the
Economists for Peace and Security.
Solow's students include Nobel Prize winners
Peter Diamond, George Akerlof, Joseph Stiglitz, and William Nordhaus, as well as
Michael Rothschild,
Halbert White,
Charlie Bean,
Michael Woodford, and
Harvey Wagner.
Solow was one of the signees of a 2018 ''amicus curiae'' brief that expressed support for Harvard University in the ''
Students for Fair Admissions v. President and Fellows of Harvard College'' lawsuit. Signers of the brief include
Alan B. Krueger,
George A. Akerlof,
Janet Yellen, and
Cecilia Rouse.
Solow was one of the supporters of
Joe Biden
Joseph Robinette Biden Jr. (born November 20, 1942) is an American politician who was the 46th president of the United States from 2021 to 2025. A member of the Democratic Party (United States), Democratic Party, he served as the 47th vice p ...
's
Inflation Reduction Act of 2022.
Solow died at his home in
Lexington, Massachusetts
Lexington is a suburban town in Middlesex County, Massachusetts, United States, located 10 miles (16 km) from Downtown Boston. The population was 34,454 as of the 2020 United States census, 2020 census. The area was originally inhabited by ...
, on December 21, 2023, at the age of 99.
Model of economic growth
Solow's model of
economic growth
In economics, economic growth is an increase in the quantity and quality of the economic goods and Service (economics), services that a society Production (economics), produces. It can be measured as the increase in the inflation-adjusted Outp ...
, often known as the
Solow–Swan neoclassical growth model as the model was independently discovered by
Trevor W. Swan and published in "The Economic Record" in 1956, allows the determinants of economic growth to be separated into increases in inputs (
labour and
capital) and technical progress. The reason these models are called "
exogenous" growth models is the saving rate is taken to be exogenously given. Subsequent work derives savings behavior from an inter-temporal utility-maximizing framework. Using his model, Solow (1957) calculated that about four-fifths of the growth in US output per worker was attributable to technical progress.

Solow also was the first to develop a growth model with different vintages of capital.
The idea behind Solow's vintage capital growth model is that new capital is more valuable than old (vintage) capital because new capital is produced through known technology. He first states that capital must be a finite entity because all of the resources on the earth are indeed limited.
Within the confines of Solow's model, this known technology is assumed to be constantly improving. Consequently, the products of this technology (the new capital) are expected to be more productive as well as more valuable.
The idea lay dormant for some time perhaps because
Dale W. Jorgenson (1966) argued that it was observationally equivalent with disembodied technological progress, as advanced earlier in Solow (1957). It was successfully advanced in subsequent research by Jeremy Greenwood,
Zvi Hercowitz and
Per Krusell (1997), who argued that the secular decline in capital goods prices could be used to measure embodied technological progress. They labeled the notion
investment-specific technological progress. Solow (2001) approved. Both
Paul Romer and
Robert Lucas, Jr. subsequently developed alternatives to Solow's neoclassical growth model.
To better communicate the meaning behind his work, Solow used a graphical design to illustrate his concepts. On the x-axis he puts capital per worker and for the y-axis he uses output per worker. The reason for graphing capital and output per worker is due to his assumption that the nation is at full employment. The first (top) curve represents the output produced at each given level of capital. The second (middle) curve shows the depreciating nature of capital which remains constantly positive. The third curve (bottom) conveys savings/investment per worker. As the old machinery wears down and breaks, new capital goods must be bought to replace the old. The point where the two lines meet is known as the steady state level, which means that the nation is producing just enough to be able to replace the old capital. Countries that are closer to the steady state level, on the left side, grow more slowly when compared to countries closer to the vertex of the graph. When countries are to the right of the steady state level, they are not growing because all the returns they create need to go to replacing and repairing their old capital.
Since Solow's initial work in the 1950s, many more sophisticated models of economic growth have been proposed, leading to varying conclusions about the causes of economic growth. For example, rather than assuming, as Solow did, that people save at a given constant rate, subsequent work applied a consumer-optimization framework to derive savings behavior endogenously, allowing saving rates to vary at different points in time, depending on income flows, for example.
In the 1980s efforts have focused on the role of technological progress in the economy, leading to the development of
endogenous growth theory (or new growth theory). Today, economists use Solow's sources-of-
growth accounting to estimate the separate effects on economic growth of
technological change
Technological change (TC) or technological development is the overall process of invention, innovation and diffusion of innovations, diffusion of technology or business process, processes.From ''The New Palgrave Dictionary otechnical change by S. ...
, capital, and labor.
In 2022, Solow was still an emeritus
Institute Professor in the
MIT economics department.
Honors
*

Grand-Cross of the
Order of Prince Henry
The Order of Prince Henry () is a Portuguese order of knighthood created on 2 June 1960, to commemorate the quincentenary of the death of the Portuguese ''infante'' Prince Henry the Navigator, one of the main initiators of the Age of Discovery. M ...
,
Portugal
Portugal, officially the Portuguese Republic, is a country on the Iberian Peninsula in Southwestern Europe. Featuring Cabo da Roca, the westernmost point in continental Europe, Portugal borders Spain to its north and east, with which it share ...
(September 27, 2006)
*Member,
American Academy of Arts and Sciences
The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...
(1956)
*Member, United States
National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...
(1972)
*Member,
American Philosophical Society
The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...
(1980)
Publications
Books
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Book chapters
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Journal articles
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Pdf.*
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::See also:
Nicholas Georgescu-Roegen and
Joseph Stiglitz.
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See also
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List of economists
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List of Jewish Nobel laureates
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Backstop resources
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Solow residual
References
Sources
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External links
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Video Interview with Solow from NobelPrize.orgArticleswritten by Solow for the
New York Review of Books
Robert M. Solow – Prize Lecture*
Robert M. Solow Papers, 1951–2011 and undated Rubenstein Library, Duke University.
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Robert M. Solowat
MITbr>
Infinite HistoryBiography of Robert M. Solowfrom the Institute for Operations Research and the Management Sciences
{{DEFAULTSORT:Solow, Robert
1924 births
2023 deaths
20th-century American economists
20th-century American non-fiction writers
21st-century American economists
21st-century American non-fiction writers
American Nobel laureates
Center for Economic and Policy Research
Columbia University alumni
Corresponding fellows of the British Academy
Distinguished fellows of the American Economic Association
Fellows of the American Academy of Arts and Sciences
Fellows of the Econometric Society
Growth economists
Harvard College alumni
Jewish American social scientists
MIT School of Humanities, Arts, and Social Sciences faculty
Members of the American Philosophical Society
Members of the United States National Academy of Sciences
National Medal of Science laureates
Nobel laureates in Economics
Presidential Medal of Freedom recipients
Presidents of the American Economic Association
Presidents of the Econometric Society
Recipients of the Pour le Mérite (civil class)
Russell Sage Foundation
United States Army personnel of World War II
United States Army soldiers