Gerard Debreu (1921–2004)

Who They Were

Gerard Debreu (1921-2004) was a French-born economist who spent much of his career in the United States, notably at the University of California, Berkeley. Trained originally in mathematics, he brought an exacting axiomatic style to economic theory and became one of the leading figures in the mathematical formalisation of general equilibrium. With Kenneth Arrow he produced the landmark existence proof of competitive general equilibrium, and he later distilled the framework into its most rigorous form in his short book Theory of Value (1959). He received the Nobel Memorial Prize in Economic Sciences in 1983 for having incorporated new analytical methods into economic theory and for his rigorous reformulation of general equilibrium. He stands with Walras, Marshall, Samuelson and Arrow among the economists who built the modern theory of equilibrium.

Key Contributions

In 1954 Debreu and Kenneth Arrow published a proof in Econometrica that, under a stated set of assumptions, a competitive general equilibrium exists, using fixed-point methods to establish one of the central results of twentieth-century economic theory. Debreu's Theory of Value (1959) presented the framework in its most austere axiomatic form, treating commodities, prices and equilibrium with the rigour of pure mathematics and setting a standard for formal economic reasoning. His work clarified exactly which assumptions, such as convexity, competitive behaviour and complete markets, are needed for a decentralised price system to be internally consistent. This axiomatic approach shaped the subsequent development of microeconomic theory. He received the Nobel Memorial Prize in 1983, eleven years after his collaborator Arrow was honoured for the shared result.

On EconRecall

French-American economist and 1983 Nobel laureate; co-author of the Arrow-Debreu existence proof and author of Theory of Value. Play the games that feature Gerard Debreu:

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