On May 15, Robert E. Lucas, undoubtedly the economist with the greatest impact on the profession in the last quarter of the 20th century, died at the age of 85. Lucas was a professor emeritus at the University of Chicago, where he received his doctorate in 1964 and to which he returned as a professor in 1974, after 10 years teaching at Carnegie Mellon.
In the 1970s, Lucas led the rational expectations revolution, along with other authors such as T. Sargent, N. Wallace, E. Prescott or R. Barro. The new macroeconomics was explicitly dynamic, taking into account that consumers and businesses use all available information to form their expectations about the future. Expectations play a role, so macroeconomic policy outcomes crucially depend on how the private sector anticipates them. For these contributions, Lucas won the 1995 Nobel Prize in Economics. As has been repeated these days, there is a macroeconomics before and after Lucas.
Some have wanted to see in the revolution led by Lucas in the 1970s a political program or a confrontation between schools or between fields of economic analysis. It is not the case. Lucas changed the way macroeconomics was done, regardless of the starting assumptions —or arrival— of the different authors. For example, Olivier Blanchard, not exactly a disciple of Lucas, but one of the fathers of the "new Keynesian macroeconomics," said not long ago about Lucas's 1972 paper on which his Nobel prize was based: "I think what he did in that article was to define the rules of the game of what a macroeconomic model had to be: it had to be dynamic, it had to have general equilibrium, it had to have optimizing agents, it had to have expectations, in this case rational expectations, but that was not essential. Basically, he defined the rules and people started playing by those rules, and that was an immense challenge.”
Lucas's investigations, always original and profound, have opened fields that have given work for years to generations of economists who have followed in his footsteps. In addition to work that changed the analysis of macroeconomics, expectations, and monetary policy, Lucas has made seminal contributions to finance, optimal taxation, firm size distribution, the structure of cities, international trade, economic growth, human capital or the economy of ideas.
Lucas is dead, but his influence will last for many years. The great poet Jaime Gil de Biedma said that it gave him a special pleasure to find some of his verses incorporated into the common language and used by someone who did not know its origin. Many young economists today write their models in the language of Robert Lucas, without perhaps being fully aware of it.
In recent years, as a member of the academic council of the Barcelona School of Economics, Lucas has visited Barcelona on various occasions, giving lectures and participating in round tables. Andreu Mas-Colell has fired him warmly: “Bob was a great economist with a remarkable intellect and a special ability to write elegantly and sharply. He was a dear friend of the economic community of Barcelona, with whom he was very generous, and who will miss him”.
