Rent, Interest and Profit Under Capitalism

To Marx, surplus value was a heterogeneous fund. Despite its homogeneous entrance into the coffers of the capitalist employer, it comes to be split into a number of kinds of individual income. Rent, interest (to the moneylending capitalist as distinguished from the more active capitalist employer), and industrial profit are only different names for different parts of the surplus value of the commodity, or the unpaid labor realized in it, and they are equally derived from this source, and from this source alone.

In another connection Marx refers to all surplus value, whatever particular form it may subsequently crystallize into, as in substance the materialization of unpaid labor. Thus, recipients of rent, interest, and profits, and subsidiary classes drawing their incomes from them, are all in effect acquiring unearned surplus, they are beneficiaries of the capitalist processes of labor exploitation. In such a society Marx and Engels, indulging in some exaggeration, hold that those of its members who work acquire nothing, and those who acquire anything do not work.