institutional economics School of economics that flourished in the U.S. in the 1920s and ’30s, which viewed the evolution of economic insti¬ tutions as part of the broader process of cultural development. Thorstein Veblen laid the foundation for institutionalism with his criticism of tradi¬ tional economic theory. He tried to replace the concept of people as the makers of economic decisions with a more realistic image of people as influenced by changing customs and institutions. John R. Commons empha¬ sized the collective action of various groups in the economy, viewed within a system of continually evolving institutions and laws. Other U.S. institu¬ tional economists include Rexford Tugwell and Wesley C. Mitchell. See also
CLASSICAL ECONOMICS, GERMAN HISTORICAL SCHOOL OF ECONOMICS.
Institutional Revolutionary Party (PRI) Political party that domi¬ nated Mexico’s political life for most of the time since its founding in 1929. It was established as a result of a shift of power from political-military chieftains to state party units following the Mexican Revolution (1910-20). Until the late 1990s, nomination to public office by the PRI virtually guar¬ anteed election, but in 1997 Mexico City elected its first non-PRI mayor. At
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instrumentalism ► integral transform I 945
the national level, the president, as leader of the party, typically selected the party’s next presidential candidate—thus effectively choosing his own suc¬ cessor. Pres. Ernesto Zedillo broke from that tradition in 1999, and the fol¬ lowing year opposition candidate Vicente Fox won the presidency, although the PRI maintained control of several state governments.
instrumentalism or experimentalism Philosophy advanced by John Dewey holding that what is most important in a thing or idea is its value as an instrument of action and that the truth of an idea lies in its usefulness. Dewey favored these terms over the term pragmatism to label the philosophy on which his views of education rested. His school claimed that cognition has evolved not for speculative or metaphysical purposes but for the practical purpose of successful adjustment. Ideas are conceived as instruments for transforming the uneasiness arising from facing a prob¬ lem into the satisfaction of solving it.
instrumentation In technology, the development and use of precise measuring, analysis, and control equipment. Among the oldest known instruments of measurement was the armillary sphere, an astronomical instrument used in ancient China and Greece. The compass was a striking advance in navigational instrumentation made about the 11th century. Theodolites made accurate determination of locations possible in the 18th century. Instrumentation developed rapidly in the Industrial Revolution. Manufacturing required precision instruments, such as the screw microme¬ ter, which could measure 0.0001 in. (0.0025 mm). The industrial appli¬ cation of electricity required instruments to measure current, voltage, and resistance. Today most manufacturing processes rely on instrumentation for monitoring chemical, physical, and environmental properties. Instru¬ ments used in medicine and biomedical research are just as varied as those in industry. See also analysis.
insulator Substance that blocks or retards the flow of electric current or heat. An insulator is a poor conductor because it has a high resistance to such flow. Electrical insulators are commonly used to hold conductors in place, separating them from one another and from surrounding structures to form a barrier between energized parts of an electric circuit and con¬ fine the flow of current to wires or other conducting paths. Electrical insulators include rubber, plastic, porcelain, and mica. Thermal insulators, which break up the heat-flow path by absorbing radiant heat, include fiberglass, cork, and rock wool.
insulin Polypeptide hormone (see peptide) that regulates blood glucose levels. Secreted by the islets of Langerhans (see Langerhans, islets of) in the pancreas when blood glucose rises, as after a meal, it helps transfer the glucose into the body’s cells to be oxidized (see oxidation-reduction) for energy or converted and stored as fatty acids or glycogen. When blood glucose falls, insulin secretion stops and the liver releases more glucose into the blood. Insulin has various related functions in the liver, muscles, and other tissues, controlling the balance of glucose with related com¬ pounds. Insulin-related disorders include diabetes mellitus and hypoglycemia. Frederick Banting and J.J.R. Macleod won a Nobel Prize in 1923 for dis¬ covering insulin, and Frederick Sanger won one in 1958 for determining its amino acid sequence.
Insull Vin-solX, Samuel (b. Nov. 11, 1859, London, Eng.—d. July 19, 1938, Paris, France) British-born U.S. public-utilities magnate. He moved to the U.S. in 1881 to become the private secretary of Thomas Alva Edi¬ son and rose to become president of the Chicago Edison Co. in 1892. By 1907 he had taken control of Chicago’s transit system. By 1912 his vast electric-power system, enlarged by various mergers, was operating sev¬ eral hundred power plants. He vigorously promoted the stock of his hold¬ ing companies. When they collapsed in 1932, he fled to Europe; extradited in 1934, he was tried three times for fraud, violation of bankruptcy laws, and embezzlement but was acquitted each time.
insurance Contract that, by redistributing risk among a large number of people, reduces losses from accidents incurred by an individual. In return for a specified payment (premium), the insurer undertakes to pay the insured or his beneficiary a specified amount of money in the event that the insured suffers loss through the occurrence of an event covered by the insurance contract (policy). By pooling both the financial contributions and the risks of a large number of policyholders, the insurer is able to absorb losses much more easily than is the uninsured individual. Insurers may offer insurance to any individual able to pay, or they may contract with members of a group (e.g., employees of a firm) to offer special rates for group insurance. Marine insurance, covering ships and voyages, is the oldest form of insurance; it originated in ancient times with loans to ship¬
owners that were repayable only on safe completion of a voyage, and it was formalized in medieval Europe. Fire insurance arose in the 17th cen¬ tury, and other forms of property insurance became common with the spread of industrialization in the 19th century. It is now possible to insure almost any kind of property, including homes, businesses, motor vehicles, and goods in transit. See also casualty insurance; health insurance; liability insurance; life insurance.
intaglio \in-'tal-yo\ Engraved or incised work on gemstones, glass, ceramics, stone, or similar material in which the design is sunk beneath the surface, the opposite of cameo and relief. It is the most ancient form of gem engraving; the earliest known Babylonian cylinder seals date from c. 4000 bc. The term intaglio is also used to describe printmaking processes in which the design is cut, scratched, or etched into a printing surface of cop¬ per, zinc, or aluminum; ink is then rubbed into the incisions or grooves, the surface is wiped clean, and the paper is embossed into the incised lines with pressure from a roller press. Intaglio processes are the most versatile of printmaking methods, as they can produce a wide range of effects.
intarsia \in-'tar-se-9\ Form of wood inlay. Italian intarsia, or inlaid mosaic of wood, which probably derived from East Asian ivory and wood inlay, found its richest expression during the Renaissance in Italy (c. 1400-1600). It was often used in panels over the backs of choir stalls and in private studies and chapels of princes.