Former Sterling Professor of Economics at Yale University, was on the Yale faculty from 1950. He retired from his teaching position in 1988. He was graduated from Harvard College summa cum laude in economics in 1939.   He received a Ph.D. in economics from Harvard in 1947 and was a Junior Fellow of the Society of Fellows for three years 1947-50, the last of which he spent at the Department of Applied Economics at the University of Cambridge, England. In 1961-62, on leave from Yale, he was a Member of President Kennedy’s Council of Economic Advisers in Washington. He was President of the Econometric Society 1958, of the American Economic Association 1971, and of the Eastern Economics Association 1977. In 1955 the American Economic Association awarded him the John Bates Clark Medal, given to one economist under age 40. He was a member of the National Academy of Sciences since 1972. In 1981 he received in Stockholm the Prize in Economic Science, established by the Bank of Sweden in Memory of Alfred Nobel. He was author or editor of sixteen books and more than four hundred articles. His main professional subjects were macroeconomics, monetary theory and policy, fiscal policy and public finance, consumption and saving, unemployment and inflation, portfolio theory and asset markets, econometrics. He wrote both for professional readers and for the general public.