It Is Whimsical to Suggest that to Increase Surplus Value, the Capitalist Cuts Down That Part of Capital Which Yields Surplus Value and Replaces It By That Part of Capital Which Can Yield None

Along these lines, then, capital seeks to satisfy its insatiable lust for increased surplus value. But here we encounter the first of the two snares which, quite apart from many other besetting difficulties, in the end brought the Marxian system, on this side· at least, to irremediable confusion. The capitalist, thirsting for surplus value, introduces more and more machinery, in order thereby to cut down the time required for the worker's maintenance and so increase the number of hours available for the production of surplus value. But, as we have seen, constant capital [machinery] yields no surplus value, which can be derived only from variable capital [wages]. There is something whimsical in the suggestion that, in order to increase surplus value, the capitalist thus cuts down that part of capital which yields surplus value, replacing it by that part of capital which can yield none. The contradiction is glaring, and Marx's explanation will resolve it only for those who can humbly say: Credo quia impossibile.

--Alexander Gray, The Socialist Tradition: Moses to Lenin (London: Longmans, Green, 1946), 312.

Capital Is Differentiated by Marx into Constant and Variable Capital (Machinery and Wages); Machinery Yields No Surplus Value; Labour Has the Whole Burden of Providing Surplus Value

It will be observed that the whole of the surplus value is derived from labour. Indeed, on the theory, as initially stated, it would appear to be derived from the individual worker; each individual worker would appear to be robbed by his own particular employer. This view is, however, modified by later elaborations of the analysis. That the surplus value comes from labour, and from labour alone, is reinforced by a distinction which is fundamental to the Marxian analysis. Capital is differentiated by Marx into constant and variable capital, corresponding broadly to the distinction between machinery and wages. But machinery yields no surplus value. It is of the essence of a machine that, in being used up, it transfers its value, neither more nor less, to the product. Whatever be thought of the validity of the argument, it has at least the advantage that it thrusts on labour the whole burden of providing surplus value. It should be noted for its significance later that industries will vary from each other according to their 'organic composition'; the ratio of constant to variable capital, low in some industries, will be high elsewhere.

--Alexander Gray, The Socialist Tradition: Moses to Lenin (London: Longmans, Green, 1946), 311.