J. S. ミル相互需要説をめぐる諸問題

W. ソーントンとW. ヒューウェルの影響

抄録

Though J. S. Mill's theory of reciprocal demand was developed in the chapter “Of International Values” in the first edition of his Principles of Political Economy (1848), Mill added new sections in the third edition (1852). In Mill's mind, the theory of reciprocal demand had not been complete, because the conditions of the Equation of Demand “might be equally satisfied by every numerical rate”. To determine a unique equilibrium, Mill introduced a new element, “the means of production available.”
In this paper, it is claimed that Mill's discussion in the new sections was influenced by William Thornton's criticism of the law of supply and demand, and by William Whewell's mathematical analysis.
Thornton's influence on Mill shows itself in Mill's recognitions of the multiple equilibria related to the price elasticity of demand. On the contrary, Whewell's influence stems from his treatment of theoretical subjects related to Mill's new approach to the theory of reciprocal demand. In particular, the amount of the inported-goods consumed in each country before trade, into which Mill translated the means of production available, is a variable in Whewell's mathematical model.