Labour was the first price, the original purchase-money that was paid for all things. It was not by gold or by silver, but by labour, that all the wealth of the world was originally purchased; and its value, to those who possess it, and who want to exchange it for some new productions, is precisely equal to the quantity of labour which it can enable them to purchase or command.7
This understanding Marx also incorporated into his own analysis:
The exchange values of commodities must be capable of being expressed in terms of something common to them all, of which thing they represent a greater or less quantity. This common "something" cannot be a geometrical, a chemical, or any other natural property of commodities . . . If then we leave out of consideration the use value of commodities, they have only one common property left, that of being products of labour.
But Marx refined the analysis of Smith and Ricardo in a very important way. It was not the particular concrete exertions of labour as such that determined exchange value. For different people with different skills take different amounts of time and use different amounts of efort to produce particular commodities:
Some people might think that if the value of a commodity is determined by the quantity of labour spent on it, the more idle and unskilful the labourer, the more valuable would his commodity be, because more time would be required in its production.8
Rather the exchange value of a commodity depends on the "socially necessary labour time":
that is required to produce an article under the normal conditions of production, and with the average degree of skill and intensity prevalent at the time . . . 9
Marx's Concepts
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