ABSTRACT
Recent advances in economic theory contributed to the reconsideration of a former analytical problem which had been neglected after World War II; that is, the relation between economic dynamics and financial structures. The introduction of the assumption of asymmetric information into macrodynamicS provided the foundations for this re-examination. This hypothesis indeed explains the emergence of banks and banking institutions which fundamentally differ from financial markets since they prevent economic agents &om settling contracts among themselves, which would typically permit an optimal allocation of resources. Because of informational asymmetries, banks cannot be characterized as pure intermediaries, as "brokers," helping the workings of the market. They appear rather to be "social accountants" who substitute a set of asymmetric relations among firms for an auction market ruled by the usual law of supply and demand (Stiglitz and Weiss 1988). This conception of financial structures will obviously exert strong effects on macrodynamics especially in the realm of the business cycles theory.
