The monetary character of trade, the existence of a common medium of exchange, is derived as an outcome of the economic general equilibrium in a class of examples. Two constructs are added to an Arrow-Debreu general equilibrium model: market segmentation with multiple budget constraints (one at...

This paper presents a class of examples where a barter economy develops through agents' optimizing decisions into a monetary economy. A barter economy with m commodities is characterized by m(m-1)/2 commodity pair trading posts for active trade of each good for every other. Monetary equilibrium...

Commodity money arises endogenously in a general equilibrium model with convex transaction cost technology and with separate budget constraints for each transaction. Transaction costs imply differing bid and ask (selling and buying) prices. The most liquid good --- with the smallest...

Jevons's double coincidence of wants condition is derived as the result of household level transaction costs in general equilibrium where N commodities are traded at (1/2)N(N-1) commodity-pairwise trading posts. Each household experiences a set-up cost on entering an additional trading post....

The microeconomic foundation of the theory of money has long represented a puzzle to economic theory. Why is there Money? derives the foundations of monetary theory from advanced price theory in a mathematically precise family of trading post models.

General equilibrium is investigated with N commodities deliverable at T dates traded spot and futures at ½ N 2T 3 dated commodity-pairwise trading posts. Trade is a resource-using activity recovering transaction costs through the spread between (bid) wholesale) and ask (retail) prices...