born Aug. 28, 1801, Gray, France died March 31, 1877, Paris French economist and mathematician. The first economist to apply mathematics effectively to the treatment of economic questions, he made important contributions with his discussion of supply and demand functions, the shifting of taxes, and problems of international trade, and he is best remembered for his discussion of strategic behaviour in a market with only two producers, a so-called duopoly. His principal work is Researches into the Mathematical Principles of the Theory of Wealth (1838)