76 ON COMPARING COMMODITIES
involves an absurdity, — that they might have
talked with equal propriety of the possibility
of comparing the distance of the sun in the
year 100 with its distance in 1800, without re-
ference to any other body in space —and that
language can scarcely be found to express the
idea in direct terms, without a palpable contra-
diction : but that such a notion has extensively
prevailed no one will doubt, who attentively
turns over the pages of the first writers on the
subject.

The following passage from the Templars’
Dialogues on Political Economy, is a conspi-
cuous instance of the error in question.

“1 wish to know,” sayshe, ¢ whether a day's
labour at the time of the English Revolution
bore the same value as a hundred years after,
at the time of the French Revolution, and if
not the same value, whether a higher or a lower.
For this purpose, if I believe that there is
any commodity which is immutable in value, I
shall naturally compare a day’s labour with that
commodity at each period. Some for instance