with equal quantities of corn, the subsistence of the labourer, than with
equal quantities of gold and silver, or, perhaps, of any other commodity.
Equal quantities of corn, therefore, will, at distant times, be more nearly
of the same real value, or enable the possessor to purchase or command more
nearly the same quantity of the labour of other people. They will do this, I
say, more nearly than equal quantities of almost any other commodity; for
even equal quantities of corn will not do it exactly. The subsistence of the
labourer, or the real price of labour, as I shall endeavour to shew
hereafter, is very different upon different occasions ; more liberal in a
society advancing to opulence, than in one that is standing still, and in
one that is standing still, than in one that is going backwards. Every
other commodity, however, will, at any particular time, purchase a greater
or smaller quantity of labour, in proportion to the quantity of subsistence
which it can purchase at that time. A rent, therefore, reserved in corn, is
liable only to the variations in the quantity of labour which a certain
quantity of corn can purchase. But a rent reserved in any other commodity is
liable, not only to the variations in the quantity of labour which any
particular quantity of corn can purchase, but to the variations in the
quantity of corn which can be purchased by any particular quantity of that
commodity.

Though the real value of a corn rent, it is to be observed, however, varies
much less from century to century than that of a money rent, it varies much
more from year to year. The money price of labour, as I shall endeavour to
shew hereafter, does not fluctuate from year to year with the money price of
corn, but seems to be everywhere accommodated, not to the temporary or
occasional, but to the average or ordinary price of that necessary of life.
The average or ordinary price of corn, again is regulated, as I shall
likewise endeavour to shew hereafter, by the value of silver, by the
richness or barrenness of the mines which supply the market with that metal,