his economic theories; and thirdly, the sociologists, that is to say those who concern themselves chiefly with Marx's theories of the laws which govern the development of the capitalistic system of society. That does not mean that this division is in any way strictly observed. To begin with, there are those who, like Bernstein, treat of all the three subdivisions of the subject, although separately from each other. Then there are those who, while making one of the divisions their chief topic permit their discussion to overlap into the other provinces.
In order that the reader may have well in mind during the following discussion the co-relation of the different parts of the Marxian system, and particularly the inseparability of his "philosophy" from his sociology and economic theory, properly so-called, a brief outline of the system is herewith given:
"In making their livelihood together men enter into certain necessary involuntary relations with each other, industrial relations which correspond to whatever stage society has reached in the development of its material productive forces. The totality of these industrial relations constitutes the economic structure of society, the real basis upon which the legal and political superstructure is built, and to which definite forms of social consciousness correspond. The method of producing the material livelihood determines the social, political and intellectual life process in general. It is not men's consciousness which determines their life; on the contrary, it is their social life which determines their consciousness.
"At a certain stage of their development the material productive forces of society come into conflict with the old conditions of production, or, what is its legal expression, with the old property relations under which these forces have hitherto been exerted. From forms of development of the productive forces these relations turn into fetters of production. Then begins an epoch of social revolution.
