In Money, Income and Time, Alvaro Cencini examines how money has been alternatively defined as a commodity and as the general equivalent of all commodities to be, subsequently, identified with the concept of num raire, and, finally, reduced to the actual notion of credit. To better clarify the terms of the problem, the writer analyses it through the main theories of money which have been developed since the works of the classical economist. The book does not take the form of a history of economic doctrines, however, since its aim is at the same time less ambitious and more precise, that is defining the true nature of money through a critical and synthetic appraisal of its various analyses.