E. E. Slutsky's enduring but enigmatic fame as an economist far outweighs the limited understanding of most interested scholars as to his very productive life and unusually wide range of research interests. To begin to compensate for this deficit a previousJHET article entitled “E.E. Slutsky: Mathematical Statistician, Economist, and Political Economist?” provided some biographical information on Slutsky's life, together with an account of a few of his little-known contributions to political economy (see Barnett, 2004b). In this current article the inception and immediate influence of Slutsky's two most famous papers in economics written in 1915 and 1927 are considered directly, in addition to further discussion of relevant aspects of Slutsky's life and times. The full significance of the content of the two groundbreaking papers will not be discussed in detail, as this has been adequately covered elsewhere (see for example Barnett 2006, Weber 1999, and Klein 1999). Rather, an attempt will be made to provide a historical and intellectual context for Slutsky's two most important contributions in economics, given that the circumstances surrounding their composition are not sufficiently well known among economists in the West.

Richard Cantillon is considered by many to be the first economic theorist. His contributions span such diverse topics as methodology, value and price theory, population, money, international trade, business cycles, the circular-flow model of the economy, and the price-specie-flow mechanism. His only known book, Essai sur la Nature du Commerce en Général (hereafter, the Essai), may represent one of the single largest steps forward in the social sciences. Many attempts have been made to classify Richard Cantillon into a well-defined school of thought and he has been claimed as a forerunner by many schools of economic thought, but for purposes of categorization, he is most often placed with the mercantilists. Cantillon lived and wrote before the Physiocrats. He was involved in John Law's Mississippi Bubble, one of the grandest attempts to actualize the mercantilist dream of increasing the supply of money, and he was involved in the merchant trade and merchant banking business, so it would be natural to consider him a mercantilist writer. Those who have classified him as a mercantilist, however, base their categorization mainly on excerpts from the Essai where Cantillon seems to display sympathy with mercantilist policy objectives in such areas as international trade, monetary policy, and economic development.

A few years ago, an article by Arnold Heertje and Peter Heemeijer (2002) triggered an articulate and stimulating debate among scholars on the intellectual origins of Paul Samuelson's multiplier-accelerator model (1939a, 1939b). The discussion, which involved the participation of Samuelson himself, centered on whether, and to what extent, Samuelson's 1939 seminal contributions were inspired by Roy Harrod's The Trade Cycle (1936). Heertje and Heemeijer argue that “there is little factual support for Samuelson's suggestion ascribing the model mainly to Alvin Hansen, his mentor in the days of the creation of the model” (Heertje and Heemeijer 2002, p. 207). Instead, they provide convincing evidence indicating that it was Roy Harrod who actually played the major role in developing the ideas leading to the multiplier-accelerator interaction. “Theoretically speaking,” they assert, “it was Harrod who provided the most important contribution to the model. His interesting 1936 work The Trade Cycle contained valuable ideas regarding the combination of the multiplier and accelerator” (p. 217).

The association of the equilibrium real rate of interest with the marginal product of capital is a staple of modern mainstream economics. Indeed, when graduate students are asked to find a typical model's equilibrium values of the real wage and interest rate, there is apparently nothing more natural than calculating the derivative of the production function with respect to labor and capital, respectively. This seems to make perfect economic sense, because under competitive conditions, the laborer gets paid the marginal product of his labor, while the capitalist gets paid the marginal product of his capital. Students can even derive the “factor-price frontier” (developed in, for example, Samuelson 1953) to show the inverse relationship between real wages and the real rate of interest, where the “factors” are, of course, labor and capital.

The history of economic thought remembers António Horta Osório for Schumpeter's reference to him in the History of Economic Analysis, in the context of a general appraisal of available works using mathematical instruments and language. This, however, does not do him justice, as he should also be praised for his pioneering interpretation of Pareto's general equilibrium. According to Stigler (1965), the definitive substitution of the cardinal utility hypothesis for the ordinal utility perspective was achieved by Johnson (1913) and Slutsky (1915). Weber (2001) discusses how far Pareto used cardinality, elects Slutsky (1915) as a pioneer of demand theory and prefers to reserve to R. G. Allen (1932–34), L. R. Klein and H. Rubin (1947–48), Samuelson (1947–48), R. C. Geary (1950–51), and Richard Stone (1954) the role of establishing ordinal utility in studying the utility function. This paper shows that Osório (1911) considered the subject of ordinalism before Johnson and Slutsky addressed the issue, as he had rejected the possibility of measuring utility and clearly stated that general equilibrium is not affected if cardinality is replaced by the ordinal conception for utility, according to Pareto's last formulation. Upon reading his book it becomes clear that not only was he perfectly aware of Edgeworth's contribution on the utility indifference curves, but also of Pareto's attempts to preserve general equilibrium from Fisher's criticism against cardinalism. Historians of economic thought have forgotten one of the early twentieth-century neoclassical economists. In this way the History of Economics has neglected an interesting proof of the consolidation of the Paretian ideas on ordinality, an issue that was an exciting and uncharted territory at that moment.