“ The labour of exploiting is just as much labour as exploited labour. ”
 Karl Marx, Das Kapital (1894). copy citation

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“Due to the alienated character of capital, its antithesis to labour, being relegated to a place outside the actual process of exploitation, namely to the interest-bearing capital, this process of exploitation itself appears as a simple labour-process in which the functioning capitalist merely performs a different kind of labour than the labourer. So that the labour of exploiting and the exploited labour both appear identical as labour. The labour of exploiting is just as much labour as exploited labour. The social form of capital falls to interest, but expressed in a neutral and indifferent form. The economic function of capital falls to profit of enterprise, but abstracted from the specific capitalist character of this function.” source