As soon as labour, in its direct form, has ceased to be the main source of wealth, then labour time ceases, and must cease, to be its standard of measurement, and thus exchange value must cease to be the measurement of use value. The surplus labour of the masses has ceased to be a condition for the development of wealth in general; in the same way that the non-labour of the few has ceased to be a condition for the development of the general powers of the human mind. Production based on exchange value therefore falls apart, and the immediate process of material production finds itself stripped of its impoverished, antagonistic form. Individuals are then in a position to develop freely.
(Grundrisse, Karl Marx, translated by David McLellan. p.142)
Marx’s meaning here is clear enough. If the tendency which exists under capitalism to produce goods more and more cheaply thanks to advances in science and technology were continued indefinitely, a stage would eventually be reached where goods could be produced so cheaply — would require so little labour power to produce — that it would no longer make sense to sell them; the only thing to do would be to give them away or make them available for people to take freely, according to their needs, without having to pay for them. In conditions of abundance it makes no sense to put a price on goods. As Marx points out, the price of a product reflects the amount of labour time needed to produce it; in the early days of capitalism when direct labour was still the main production force, pricing goods according to the time it took an average individual using average techniques of production to produce them had a certain logic. However, when the main productive force has become science and technology, in which labour intervenes not as an individual contribution by a skilled worker but as the co-operative effort of a collective workforce, then it no longer makes sense to measure output in terms of its labour time content; it no longer makes sense to put a price on goods and sell them. The abundance made possible by modern technology points to a different system in which goods will be freely available.
Of course capitalism will never reach this stage of its own accord. It will not automatically collapse and be replaced by a society of free access to goods and services. It merely tends to make the price system — in fact, the whole money-wages-prices system — redundant. It is in this sense that it paves the way for a society of free access. But the end of “production based on exchange value” has to be a conscious political act.