MARX'S THEORY OF MONEY 61 the "market rate of interest'. . . The sole precondition of the division is then that the rate of interest cannot be zero, and that it cannot be equal to or exceed the average rate of profit. This contingent character of the rate of interest is tied to the special character of the capital market" (p 89). This view sharply differs from that of Keynes, who considers the rate ofinterst as an important factor responsible for the determination of investment through its influence on the marginal efficiency of capital. In a discussion on the balance of payments and the demand for world money, Marx pays attention to international monetary problems, of the determination of the rate of exchange, and shows how variations of the exchange rate depend mainly on a specific demand for foreign money for international transactions. Although Marx did not construct a theory of the business cycle, de Brunhoff presents his views, in the section on "Credit and Business Cycle" of her book, which examines the financal cycle, namely, financial crisis and monetary crisis, the monetary theory of financial structure and so on. Last, but not the least, Marx's views on monetary policy are outlined. Had Marx any clear-cut monetary policy like the present monetary theorists whose explicit aim is to improve monetary policies in modern societies? The study of Marx's monetary theory shows he had little interest in this direction. In his monetary policy he tries to present a correct understanding of the relation of money to the production and exchange of commodities which is necessary to understand and evaluate the performance of the monetary policy in a capitalist economy. The main virtues of this short book lie in its effort to put together all that Marx wrote on money, and in its coherent presentation within a general theoretical framework. Marx on Money, besides being a good introduction to Marx's theory of money, also provides an instructive guideline for the general structure and argument of the three volumes of Capital. De Brunhoff has followed Marx faithfully and sometimes has, if necessary, clarified the issues and pointed out the errors committed by other Marxists (for example, Paul Sweezy, Rosa Luxemburg) in their analysis of Marx. DEBESH GHAKRABORTY (The idea of reviewing this book was stimulated by a talk given by de Brunhoff at a workshop in Marxian economics at New York University, Jfew York) in the recent past).