The Role of Demand in Macroeconomics

Abstract

I argue that the standard approach represented by real business cycle theory is misguided, and that a fundamentally different approach is necessary. The new approach, based on the method of statistical mechanics, leads us to a new concept of “equilibrium”. In equilibrium we must have a distribution of productivities rather than a unique level of productivity. We then find that demand plays a crucial role in the determination of the aggregate output, as the old Keynesian economics claims. I show that the demand constraint is important not only in short-run but also in long-run economic growth.