DUPUIT, ARSNE-JULES-TIENNE-JUVNAL

born May 18, 1804, Fossano, Piedmont, French Empire [now in Italy] died Sept. 5, 1866, Paris, Fr. French engineer and economist who was one of the first to analyze the cost-effectiveness of public works. Dupuit studied at the cole Polytechnique (Polytechnic School) in Paris and then joined the civil-engineering corps, rising to the rank of inspector general of bridges and highways. Through his professional work, Dupuit became interested in the economic problems associated with constructing public works and charging for their use. He concentrated on the benefits of public works over and above their cost to users. He was one of the first to develop the concept of a demand curve, and he pioneered the use of the concept of diminishing marginal utility. In determining the cost-benefit of public works, he was led to the concept that was later, by British economist Alfred Marshall, termed consumer surplus, i.e., the welfare enjoyed by a consumer in excess of the price paid. Dupuit is undoubtedly the founder of cost-benefit analysis of public works. He also analyzed price elasticity, leading to, among other ideas, the development of what has become known as the Laffer curve of taxation.