Supply

The larger the number of beavers I have eaten, the smaller the number of deer I am willing to trade you in order to acquire one more beaver. The larger the number of beavers you have hunted, the larger the number of deer you demand from me if you are to barter me one more beaver. As we become, each in his own way, more and more fed up, we approach a point where my demand curve cuts your supply curve, a point at which equilibrium quantity coexists with equilibrium price, a point at which there is no tendency for any further change to take place. Once that point has been reached the tâtonnement and the auctioneer are declared surplus to requirements, the numéraire is served up for dinner with a small portion of manna from Heaven, and the student turns to the next question on the examination-paper confident in the expectation that he will soon be certified as an economist. When the scripts are marked, however, it is found that one idle boy, while drawing the usual Marshallian cross, as indeed he should, has dared to introduce a credo all his own: ‘In the real world a simple doctrine of value is worse than none.’1 We, the examiners, are neither amused nor satisfied.