Since then, however, a number of Marxists have been able completely to rescue Marx's position by challenging the fundamental assumption made by von Bartkiewicz, Sweezy, Shaikh and many others-the reliance on simultaneity.25 The method of simultaneous equations assumes that the prices of the inputs to production have to equal the prices of the outputs. But they do not. The outputs are produced after the inputs have gone into production. Or, to put it another way, the value of the inputs for a process A will differ from that of the same inputs for a later process B-even if in terms of their physical composition as use values they are identical. The value of a ton of steel used to make a machine today will not be the same as the value used to make an identical machine next week. 26
But, argue the critics of Marx, this still leaves the inputs into production as prices, not as values, and to reduce them to labour values involves an infinite regress. The investment need to produce the inputs needs to be broken down into labour values, but that is not possible without breaking down in turn the investment needed to produce it, ad infinitum.
There is a simple response to those who pose the problem like this: Why? Why do the investments needed to produce the inputs have to be broken down in terms of their labour value when they themselves were produced?27
The starting point for looking at any cycle of production is the money price of the inputs needed to undertake it. The exercise of labour in the production process then adds a certain amount of new value, which forms the basis of the new commodity, the price of which in turn is formed through the movement of surplus value from capitalists who would otherwise get a higher than average rate of profit to those who would get a lower one.
Marx and His Critic
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