ABSTRACT. The notion social class attains a well-defined theoretical content in the works of the classical political economists, who defined classes on the basis of the specific income form that each category of people (class) obtains. This approach to class constitutes a first form of a "friendly merger" between political economy and sociology. When combined with the classical labor value theory, it has led to a theory of class exploitation of the laboring class by the capitalist class. As economic theory became increasingly apologetic after the "Marginalist Revolution" (setting itself the aim of justifying capitalism), the theory of class has been totally banished from the corpus of "modern (neoclassical) economic science." This paper claims that the scientific elements inherent in classical political economy's class theory were preserved by the Marxist class theory, which further revolutionized the classical approach, creating a new, purely non-economistic and non-mechanistic "relationist" class theory, an d forming thus a vivid economic-sociological approach to social classes. On the basis of the Marxist approach, complex problems concerning the class structure of contemporary societies can be tackled.
I
Introduction
THE THEORY OF CLASSES MAKES UP one of the most controversial chapters of the social sciences, in the sense that it comprises a forefront of confrontation between the different theoretical schools that are formulated within the field.
To clarify what is to follow, I therefore reiterate the position that was stated by de Ste. Croix: "It seems to me hardly possible for anyone today to discuss problems of class, and above all class struggle (or class conflict), in any society, modern or ancient, in what some people would call an 'impartial' or 'unbiased' manner, I make no claim to 'impartiality' or 'lack of bias,' let alone 'Wertfreiheit,' freedom