a1 Purdue University, West Lafayette, IN, USA.
Nearly a half-century has passed since Ronald Meek (1956, p. 63) warned us that Adam Smith's notion of the labor commanded by a commodity in the marketplace is to be understood not as an expression of the “substance” of value, varying “directly with the quantity of social labor used to produce” the object, but rather as nothing more than a unit of value measure with no fixed relationship to the labor “embodied” in production. It was this distinction that he sought to fix in our minds with his memorable image of the magnet. Indeed, it is more than three times as long since John Stuart Mill (1848, p. 568) conveyed the same distinction with his particularly apt metaphor of “the thermometer and the fire.” Further, it is now forty years since Mark Blaug (1959), reminding us of that distinction, returned our attention to Smith's use of his measure as an expression of potential productive capacity (a view advanced earlier yet by Hla Myint 1948, pp. 20–21 and by Meek 1956, p. 65), but one that conveys a subjective dimension as well. Yet in spite of a now widespread concurrence in this reading, the “legend” that Smith's concept of labor commanded is to be understood as expressing, in some way, price ratios proportional to ratios of labor embodied in production remains remarkably resilient.