Conclusions
In the end we wonder which result our reappraisal of a repeatedly debated issue has achieved. First, we hope that the argument developed above has identified a minimal set of measurable magnitudes that are observable in principle and, for a given value of either the rate of profit or the real wage rate, are the direct determinants of the prices of production in the presence of nonproduced commodities and in a self-contained period of production.
The flow of an exhaustible resource used for the production of commodities belongs to such a minimal set of measurable magnitudes; however, its total stock left in the ground does not. Secondly, the previous argument has led us to revisit the notions of price of production, which have been illustrated by means of two different metaphors: the center of gravity in Garegnani versus the snapshot in Roncaglia. The main divide between our view and the latter, and perhaps the former as well, rests on our asserted correspondence between prices of production and quantities in demand and supply. Such a correspondence neither implies nor presupposes that Sraffa’s equations are a sort of slice of a Walrasian general equilibrium model that is lurking in the background.