Ante litteram “cooperative thinking”: Ramsey, Harrod and Keynes about the Life Cycle Hypothesis and economic growth

In this paper we reconstruct the early insights that Frank Ramsey and Roy Harrod provided into the Life Cycle Hypothesis (LCH) in their 1928 and 1948 contributions, respectively, well before the publication of the 1954 Modigliani-Brumberg (M-B) formalized framework. In 1970 Modigliani acknowledged Harrod’s forerunning contribution to the LCH, that was included in the Lecture Two of his 1948 volume Towards a Dynamic Economics. Yet, he never mentioned Ramsey’s insight on the LCH, presented in the pathbreaking article “A mathematical theory of saving” published in The Economic Journal in 1928. A fact that is at odds with the large credit that the two English economists, who were both mentored by John M. Keynes, had in the academic community since 1950s. Adding oddity to oddity, although largely drawing from Ramsey’s analytical framework, in his book Harrod himself cites Ramsey’s work only in a footnote on a secondary issue. We offer in this work a reconstruction of these facts, ending with the analysis of the interplay between Harrod and Keynes in the elaboration of Harrod’s Fundamental Equation on economic growth, which also emerges in M-B’s LCH model.