DEFINITION of Gerard Debreu

Gerard Debreu was a mathematician and economist who was born in France but spent most of his academic career in the United States and most particularly at University of California at Berkeley. As the primary focus of his research was general equilibrium theory, his seminal works yielded his interests towards a possible balance between supply and demand that would trounce conventional economic theory about the nature of the marketplace.


Born in 1921, Gerard Debreu was quickly orphaned as a youngster when his father committed suicide and his mother died of natural causes. Born into a mercantile family who made lace, Debreu showed early promise in mathematics and was granted his high school with an eye towards prepping for the national exams to a grande ecole, an ambition achieved when he was admitted to École Normale Supérieure in Paris in 1941.

Debreu studied there for three years, but as he was preparing to take the final examinations, the landings in Normandy began and Debreu promptly enlisted in the French army. He was sent to Algeria for training and then released from service in 1945 after serving in French-occupied Germany. Towards the end of that year and extending into early 1946, Debreu took his examination Agregation de Mathematiques but began to make a transition from mathematics to economics, influenced in no small part by the general equilibrium theory of Leon Walrus and the Bourbaki brothers also. By 1948, his scholarship and interest in the issues of economists led him to be awarded a Rockefeller scholarship to visit and teach in the United States.

'Gerard Debreu' and Seminal Theories

Having joined the faculty at the University of Chicago in 1950 with intermittent travel back and forth to Paris, Debreu began working on the seminal theories that would earn him a career, the respect of other economists, and eventually attract the attention of the Nobel Committee. In 1954, along with Kenneth Arrow as co-author, he produced a paper titled “Existence of an Equilibrium for a Competitive Economy,” wherein the pair was able to prove the mathematical potential of a stable economy where supply and demand are on similar curves. The paper attracted attention for other noted economists and Debreu was offered a position at Yale University.

In 1958, Debreu would offer forth an elaboration of this theory within the pages of his most famous book, “Theory of Value: An Axiomatic Analysis of Economic Equilibrium,” a work that would prove itself over time as a seminal classic of modern economics. Later, between the years of 1960-1961, Debreu would work at Stanford’s Center for Advanced Study in the Behavioral Sciences towards the development of a general theory within the economics of the existence of an economic equilibrium.

In 1962, Debreu was given a position at UC Berkeley where he would find a permanent placement along with the titles of University professor and Class of 1958 Professor of Economics and Mathematics Emeritus. In 1976, he received the French Legion of Honor award and in 1983, he received the Nobel Prize in Economics. He died in December 2004.