Arsène Jules Étienne Juvenal Dupuit (18 May 1804 – 5 September 1866) was a French civil engineer and economist.
He received a Légion d'honneur in 1843 for his work on the French road system, and shortly after moved to Paris.
Conversely as the quantity rises (people allowed on the bridge), the willingness of a person to pay for that good (the price) declines.
Dupuit's reputation as an economist does not rest on his advocacy of laissez-faire economics (he wrote "Commercial Freedom" in 1861) but on frequent contributions to periodicals.
Wanting to evaluate the net economic benefit of public services, Dupuit analysed capacities for economic development, and attempted to construct a framework for utility theory and measuring the prosperity derived with public works.