AT DIFFERENT PERIODS. 77

have imagined, that corn is of invariable value,
and supposing me to adopt so false a notion, I
should merely have to inquire what quantity of
corn a day’s labour would exchange for at each
period, and I should then have determined the
relations of value between labour at the two
periods *.”

It scarcely needs pointing out, after the explanation
 I have given, that no relation of value
could exist between labour at these two periods:
the only point to be ascertained would be, whether
 the same or a different relation existed at
both periods, between corn and labour, and this
would be equally well ascertained, without supposing
 the condition of corn being immutable
in value. This very supposition implies, either
that the fact which it is wished to ascertain
is already ascertained, or, that the value of
corn at one period may be compared with the
value of corn at another period, with no reference
 to anv other commodity in the world.

* Dialogue v, T.ondon Magazine for May, p. 558.