Raúl Prebisch (April 17, 1901April 29, 1986) was an Argentine economist known for his contributions to structuralist economics such as the Prebisch–Singer hypothesis, which formed the basis of economic dependency theory. He became the executive director of the Economic Commission for Latin America (ECLA or CEPAL) in 1950. In 1950, he also released the very influential study The Economic Development of Latin America and its Principal Problems. Early years He was born in Tucumán, Argentina, to German settlers and studied at the University of Buenos Aires Faculty of Economic Sciences, where he later taught. His brother Alberto Prebisch became a well-known architect. As a young man his writing was marked by a complete adherence to the idea of free-trade but in the 1930s, as a result of the Great Depression he "converted" to protectionism. His previous beliefs had been supported by the spectacular economic growth of Argentina from the 1860s to 1920s as the country exported a large amount of beef and wheat to the United Kingdom. However, by the 1930s the Great Depression and the growing economic dominance of the United States, which exported beef and wheat rather than buying them, had significantly hurt the Argentinian economy. Centre and periphery The plight of Argentina forced Prebisch to reexamine the principle of comparative advantage described by David Ricardo, marking the creation of a new school of economic thought in the late 1940s. Prebisch separated out the purely theoretical aspects of economics from the actual practice of trade and the power structures that underlie trading institutions and agreements. His resulting division of the world into the economic "centre", consisting of industrialised nations such as the U.S., and the "periphery", consisting of primary producers, remains used to this day. As president of the Central Bank of Argentina he had noticed that during the Great Depression the prices of primary products, such as agricultural goods, fell much more than the prices of manufactured secondary products. However, he and his colleagues were unable to specify the exact mechanism for the difference, beyond hypothesizing that supply conditions of primary and secondary goods were different in that while farmers planted the same amount every year regardless of the price they would get, manufacturers were able to reduce or increase capacity to respond to expected changes in demand. However, these ideas remained unformed until he was appointed executive director of the Economic Commission for Latin America (ECLA