James Tobin on Overlapping Generations Models and the Microeconomic Foundations of Macroeconomics Reconsidered

Abstract

The American Keynesian economist and Nobel laureate James Tobin entitled his contribution to the inaugural issue of Journal of Money, Credit and Banking “A General Equilibrium Approach to Monetary Theory” (1969) yet he was sharply critical of the version of general equilibrium analysis used in the now-prevalent dynamic stochastic general equilibrium (DSGE) approach to macroeconomic modeling. He also rejected claims that overlapping generation (OLG) models provided a choice-theoretic foundation for the holding of fiat money, denying that the assumption that people held fiat money because no other asset existed was less arbitrary than allowing costs of transactions between assets to be non-zero. Yet, while not accepting OLG as the explanation of why people hold fiat money, Tobin, in a series of articles from 1967 to 1983 (some joint with Walter Dolde), placed the life-cycle model of consumption and saving (whose origins he attributed to an earlier Yale economist, Irving Fisher) into an OLG setting. This article examines Tobin’s critiques of DSGE and OLG modelling in macroeconomics, what he meant by “a general equilibrium approach to monetary theory,” and his contribution placing the life-cycle model in an OLG setting.