Irving Fisher was born in Saugerties, New York, in 1867. He received a doctorate at Yale in 1891 in economics and mathematics. He taught mathematics at Yale from 1895 until he joined the political economy faculty (an older term for economics). In 1935, he became professor emeritus. He was one of the earliest American neoclassical economists, though his later work on debt deflation has been embraced by the post-Keynesian school. Although he damaged his reputation by insisting throughout the Great Depression that recovery was imminent, contemporary economic models of interest and capital are based on Fisherian principles. Similarly, monetarism is founded on Fisher’s principles of money and prices. Fisher made important contributions to the fields of statistics, econometrics and index number theory. Joseph Schumpeter described him as “the greatest economist the United States has ever produced”, an assessment later repeated by James Tobin and Milton Friedman. Fisher was also an active social and health campaigner, as well as an advocate of vegetarianism, prohibition and eugenics. In 1893, he married Margaret Hazard. He died in New York City in 1947, at the age of 80.
Key works: 1906 The Nature of Capital and Income, 1911 The Purchasing Power of Money, 1922, The Making of Index Numbers, 1930 The Theory of Interest, 1932, Booms and Depressions