Trevor Evans writes:
"Thus although Marx's analysis of creidt money as permitting a displacment of the process of social validation is an insightful means of linking the expansion of credit to the process of production, this cannot be used to justify his view--part argued, part assumed--that credit money can in practice never be more than a substitute for real money. "Following the approach of [Suzanne]deBrunhoff and the Regulation school, the modern money monetary system can be understood asa hierarchy involving private bank money, central bank money, and international money. In this system, credit money is created by private banks and effectively guaranteed by the central bank. But while the system depends on active state management, the central bank does not control the creation of private bank money. A key feature of the system is that the process of social validation must be understood not as something that is ever accomplished definitively, but as something that,while it can be deferred at one level of the hierarchy, will reassert itself at a higher level. Consequently, the contradictions of capitalist accumulation which in the 19th century manifested themselves as an inability to sell commodities, can be displaced and will ultimately be manifestd in the markets for foreign exchange, where the different systems of national money are brought into relation with one another."
In "Issues in Marxian Theory of Money and Credit", ed Paolo Giusanni. International Journal of Political Economy, vol 27, no 1 (Spring 1997)