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 on an average according to the quantity of labour employed to obtain them; and in comparing the values of commodities so produced at one period with the commodities so produced at the other period, it seems scarcely possible not to allow that those commodities which had been produced at each period with exactly the same quantity of labour of the same description, and brought to market immediately, would be supplied ordinarily in the same proportion to the demand at each period, and be considered as of the same value.

Now in regard to commodities produced by labour alone, and brought to market immediately, it is evident that the labour employed upon them must on an average be precisely the same as the labour which they will command. But it is allowed that the relations of all commodities to one another, however variously composed, are at the same time and place, exactly in proportion to the quantity of labour which they will severally command. Consequently if the values of the commodities produced by labour alone in the time of Edward III. be to the values of commodities produced by labour alone in the time of William IV. as the quantities of labour which at each period they will command, it follows necessarily, that the values of all and each of the commodities in the time of Edward III. however variously composed, must be to the values of all and each of the commodities in the time of William IV. however composed, in the proportion of the quantity of labour which all and each will severally command.

The value, therefore, of any commodity at either period, whether arising from the intrinsic cause of labour alone, or from labour combined in various proportions with profits, rent, and taxes, or affected by temporary scarcity or abundance, will be measured by the quantity of the labour of each period which it will command.

And that the correctness of so measuring the values of commodities, will not be in any degree disturbed by the varying quantity of produce, or the varying