The economist **Gérard Debreu** was awarded the 1983 **Nobel Prize in Economics** for his work “introducing new analysis methods in economic theory and for a rigorous reformulation of the theory of general equilibrium”. This brilliant economist was born in Calais on 4 July 1921, and it was in Calais that he completed his primary and secondary schooling, graduating in 1939. However, instead of continuing his studies in a Parisian lycée, he was admitted directly to a higher mathematics class (because of the war) and then to a special mathematics course in Grenoble.

He attended** the École Normale Supérieure in 1941**. Still, due to the war situation, he was unable to take the mathematics teaching exams, so he joined the French army after the landing and was assigned to the German occupation troops until July 1945. However, things changed when he returned to France, as he sat the competitive examinations to become a mathematics teacher, coming first in his class in 1946. This period allowed him to have his first contact with economic sciences, more specifically with **the theory of general equilibrium**, through the work of M. Allais (who would go on to win **the Nobel Prize for Economics in 1989**) entitled “A la recherche d’une discipline économique” written in 1943.

**Gérard Debreu** held a research post at **the Centre National de la Recherche Scientifique** (**CNRS**). He then spent the next two years working on his thematic transformation from mathematics to economics. At the end of 1948, he was awarded a **Rockefeller scholarship** to the United States, where he spent time at various universities such as **Harvard**, **Berkeley**, **Columbia**, **Chicago**, etc. Finally, he was at the University of Chicago, where he was awarded a scholarship to study mathematics and economics. At the University of Chicago, he was offered the post of researcher at the **Cowles Commission**, where he remained active for eleven years from 1950 to 1961.

His doctoral thesis in science was defended in 1956, a work that allowed him to create the basis for his most famous work, “** Theory of Value: An Axiomatic Analysis of Economic Equilibrium**“, published in 1959. Then, in 1962, he accepted a position at the University of Berkeley, where he remained except for stays at European, New Zealand and, of course, American universities.

## The work of Gérard Debreu

As already mentioned, his great work was **Theory of value: An Axiomatic Analysis of Economic Equilibrium**, where he provided **mathematical foundations **for understanding the phenomenon of equilibrium established in **supply and demand** also described by **Adam Smith** in 1776 as the “invisible hand” that leads selfish men unknowingly to help society. **Gérard Debreu** also developed methods to analyse the factors influencing equilibrium.

“Among all the Nobel laureates in economics, I have done the most abstract work”, were **Gérard Debreu**‘s own words in 1985, just two years after receiving the Nobel Prize for his contribution to **the theory of economic equilibrium**. Nevertheless, he chose to remain a theoretician all his life, his **mathematical models **providing the basis for generations of economists to explore how individuals and firms interact and how a **market economy **really works.