Formation of Cartels in Large Markets

The von Neumann-Morgenstern concept of solution is applied to nonatomic pure exchange markets consisting of a finite number of different types of trader, initially owning disjoint sets of goods. It is proved that if all traders of each type form a cartel and behave like a single (atomic) trader (their "representative"), then one gets solutions of the original market from those of the finite market of the representatives, and all solutions are obtained in this manner-i.e., the market must organize itself in cartels, and this will indeed be stable.