Ирвинг Фишер: Экономист, пионер экономиметриясы және қарыз дефляциясының теориясы

American economist (1867–1947)
Fisher made important contributions to utility theory and general equilibrium. He was also a pioneer in the rigorous study of intertemporal choice in markets, which led him to develop a theory of capital and interest rates. Fisher was also a pioneer of econometrics, including the development of index numbers. Some concepts named after him include the Fisher equation, the Fisher hypothesis, the international Fisher effect, the Fisher separation theorem and Fisher market. Fisher was perhaps the first celebrity economist, but his reputation during his lifetime was irreparably harmed by his public statement, just nine days before the Wall Street Crash of 1929, that the stock market had reached "a permanently high plateau". His subsequent theory of debt deflation as an explanation of the Great Depression, as well as his advocacy of full reserve banking and alternative currencies, were largely ignored in favor of the work of John Maynard Keynes. Interest in him has also grown in the public due to an increased interest in debt deflation after the Great Recession. Fisher was one of the foremost proponents of the full reserve banking, which he advocated as one of the authors of A Program for Monetary Reform where the general proposal is outlined.

Fisher was born in Saugerties, New York. His father was a teacher and a Congregational minister, who raised his son to believe he must be a useful member of society. Despite being raised in religious family, he later on became an atheist. As a child, he had remarkable mathematical ability and a flair for invention. A week after he was admitted to Yale College his father died, at age 53. Irving then supported his mother, brother, and himself, mainly by tutoring. He graduated first in his class with a BA degree in 1888, having also been elected as a member of the Skull and Bones society. In 1891, Fisher received the first PhD in economics granted by Yale. His faculty advisors were the theoretical physicist Willard Gibbs and the sociologist William Graham Sumner. As a student, Fisher had shown particular talent and inclination for mathematics, but he found that economics offered greater scope for his ambition and social concerns. His thesis, published by Yale in 1892 as Mathematical Investigations in the Theory of Value and Prices, was a rigorous development of the theory of general equilibrium. When he began writing the thesis, Fisher had not been aware that Léon Walras and his continental European disciples had already covered similar ground. Nonetheless, Fisher's work was a very significant contribution and was immediately recognized and praised as first rate by such European masters as Francis Edgeworth. After graduating from Yale, Fisher studied in Berlin and Paris. From 1890 onward, he remained at Yale, first as a tutor, then after 1898 as a professor of political economy, and after 1935 as professor emeritus. He edited the Yale Review from 1896 to 1910 and was active in many learned societies, institutes, and welfare organizations. He was elected to the American Academy of Arts and Sciences in 1912. He was president of the American Economic Association in 1918. He was elected to the American Philosophical Society in 1927. The American Mathematical Society selected him as its Gibbs Lecturer for 1929. A leading early proponent of econometrics, in 1930 he founded, with Ragnar Frisch and Charles F. Roos the Econometric Society, of which he was the first president. Fisher was a prolific writer, producing journalism as well as technical books and articles, and addressing various social issues surrounding the First World War, the prosperous 1920s and the depressed 1930s. He made several practical inventions, the most notable of which was an "index visible filing system" which he patented in 1913 and sold to Kardex Rand (later Remington Rand) in 1925. This, and his subsequent stock investments, made him a wealthy man until his personal finances were badly hit by the Crash of 1929. 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, a granddaughter of Rhode Island industrialist and social reformer Rowland G. Hazard. in New York City in 1947, at the age of 80.

James Tobin, writing on the contributions of John Bates Clark and Irving Fisher to neoclassical theory in America argues that American economists contributed in their own way to the preparation of a common ground after the neoclassical revolution. In particular Clark and Irving Fisher "brought neoclassical theory into American journals, classrooms, and textbooks, and its analytical tools into the kits of researchers and practitioners." Already in his doctoral thesis, "Fisher expounds thoroughly the mathematics of utility functions and their maximization, and he is careful to allow for corner solutions." Already then, Fisher "states clearly that neither interpersonally comparable utility nor cardinal utility for each individual is necessary to the determination of equilibrium." In reviewing the history of utility theory, economist George Stigler wrote that Fisher's doctoral thesis had been "brilliant" and stressed that it contained "the first careful examination of the measurability of the utility function and its relevance to demand theory." This model, later generalized to the case of K goods and N periods (including the case of infinitely many periods) has become a standard theory of capital and interest, and is described in Gravelle and Rees, and Aliprantis, Brown, and Burkinshaw. This theoretical advance is explained in Hirshleifer.

Following the stock market crash of 1929, and in light of the ensuing Great Depression, Fisher developed a theory of economic crises called debt deflation, which attributed the crises to the bursting of a credit bubble. Initially, during the upswing over confident economic agents are lured by the prospect of high profits to increase their debt in order to leverage their gains. According to Fisher, once the credit bubble bursts, this unleashes a series of effects that have serious negative impact on the real economy:
Debt liquidation and distress selling. Contraction of the money supply as bank loans are paid off. A fall in the level of asset prices. A still greater fall in the net worth of businesses, precipitating bankruptcies. A fall in profits. A reduction in output, in trade and in employment. Pessimism and loss of confidence. Hoarding of money. A fall in nominal interest rates and a rise in deflation adjusted interest rates. Crucially, as debtors try to liquidate or pay off their nominal debt, the fall of prices caused by this defeats the very attempt to reduce the real burden of debt. Thus, while repayment reduces the amount of money owed, this does not happen fast enough since the real value of the dollar now rises ('swelling of the dollar'). This theory was largely ignored in favor of Keynesian economics, in part because of the damage to Fisher's reputation caused by his public optimism about the stock market, just prior to the crash. Debt deflation has experienced a revival of mainstream interest since the 1980s, and particularly with the Late 2000s recession. Steve Keen predicted the 2008 recession by using Hyman Minsky's further development of Fisher's work on debt deflation. Debt deflation is now the major theory with which Fisher's name is associated. Irving Fisher stated on October 21 that the market was "only shaking out of the lunatic fringe" and went on to explain why he felt the prices still had not caught up with their real value and should go much higher. On Wednesday, October 23, he announced in a banker's meeting "security values in most instances were not inflated." For months after the Crash, he continued to assure investors that a recovery was just around the corner. Once the Great Depression was in full force, he did warn that the ongoing drastic deflation was the cause of the disastrous cascading insolvencies then plaguing the American economy because deflation increased the real value of debts fixed in dollar terms. Fisher was so discredited by his 1929 pronouncements and by the failure of a firm he had started that few people took notice of his "debt deflation" analysis of the Depression. People instead eagerly turned to the ideas of Keynes. Fisher's debt deflation scenario has since seen a revival since the 1980s.

In 1898, Fisher was diagnosed with tuberculosis, the same disease that had killed his father. He spent three years in sanatoria, finally making a full recovery. That experience sparked in him a vocation as a health campaigner. He was one of the founders of the Life Extension Institute, under whose auspices he co authored the bestselling book How to Live: Rules for Healthful Living Based on Modern Science, published in 1915. He advocated regular exercise and the avoidance of red meat, tobacco, and alcohol. In 1924, Fisher wrote an anti smoking article for the Reader's Digest, which argued that "tobacco lowers the whole tone of the body and decreases its vital power and resistance [it] acts like a narcotic poison, like opium and like alcohol, though usually in a less degree". Fisher supported the legal prohibition of alcohol and wrote three booklets defending prohibition in the United States on grounds of public health and economic productivity. As a proponent of Eugenics he helped found the Race Betterment Foundation in 1906. He also defended eugenics, serving in the scientific advisory board of the Eugenics Record Office and as first president of the American Eugenics Society. When his daughter Margaret was diagnosed with schizophrenia, Fisher had her treated at the New Jersey State Hospital at Trenton, whose director was the psychiatrist Henry Cotton. Cotton believed in a "focal sepsis" theory, according to which mental illness resulted from infectious material in the roots of teeth, bowel recesses, and other places in the body. Cotton also claimed that surgical removal of the infected tissue could alleviate the patient's mental disorder. At Trenton, Margaret Fisher had sections of her bowel and colon removed, which eventually resulted in her death. Irving Fisher nonetheless remained convinced of the validity of Cotton's treatment.