There is, however, a limit to the capacity of this method to counter the downward pressure on profit rates-the number of hours in the working day. The number of hours per day that go into providing for the upkeep of the worker can fall from four to three, or from three to two, but it cannot fall below zero! By contrast investment in means of production can increase without limit.42
Take the example of a firm which employs a static workforce of 30,000. Even if it worked them as long as was physically possible each day (say, 1 6 hours) and paid them no wages, its daily profit could not exceed the value embodied in 30,000 x 16 hours labour. This is a limit beyond which profit cannot grow. But there is no such limit on the degree to which investment can grow (and with such a high level of exploitation there would be an enormous quantity of old surplus value to be turned into new enlarged investment). So a point will be reached where profits stop growing, even though competition forces the level of investment to continue rising. The ratio of profits to investment-the rate of profit-will tend to fall.
The second "countervailing factor" is that the increase in the productivity of labour means there is a continual fall in the amount of labour time-and therefore of value-needed to produce each unit of plant, equipment or raw materials. The "technical composition of capital" -the physical ratio of factories, machines, etc to workers-grows. But the factories, machines and so on get cheaper to buy. And so the expansion of investment in value terms would be rather slower than the expansion in material terms. This would counteract to some extent the tendency for the value of investment to outstrip the growth in surplus value.
There have been claims that this is more than just a "countervailing tendency" to Marx's law and in fact completely destroys it. Critics argue, using mathematical equations provided by Okishio, that technical progress means that goods are always being produced more cheaply than in the past.43 If a rise in the ratio of dead to living labour in a certain industry increases productivity, the price of its output will fall compared to the output of other industries. But that in turn will reduce the costs of investment in these industries and its ratio to labour. Lower investment costs will lower the organic composition of capital and raise the rate of profit.
The Dynamics of the System
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