The distinction between the real and the nominal price of commodities and
labour is not a matter of mere speculation, but may sometimes be of
considerable use in practice. The same real price is always of the same
value; but on account of the variations in the value of gold and silver, the
same nominal price is sometimes of very different values. When a landed
estate, therefore, is sold with a reservation of a perpetual rent, if it is
intended that this rent should always be of the same value, it is of
importance to the family in whose favour it is reserved, that it should not
consist in a particular sum of money. Its value would in this case be liable
to variations of two different kinds: first, to those which arise from the
different quantities of gold and silver which are contained at different
times in coin of the same denomination; and, secondly, to those which arise
from the different values of equal quantities of gold and silver at
different times.

Princes and sovereign states have frequently fancied that they had a
temporary interest to diminish the quantity of pure metal contained in their
coins; but they seldom have fancied that they had any to augment it. The
quantity of metal contained in the coins, I believe of all nations, has
accordingly been almost continually diminishing, and hardly ever augmenting.
Such variations, therefore, tend almost always to diminish the value of a
money rent.

The discovery of the mines of America diminished the value of gold and
silver in Europe. This diminution, it is commonly supposed, though I
apprehend without any certain proof, is still going on gradually, and is
likely to continue to do so for a long time. Upon this supposition,
therefore, such variations are more likely to diminish than to augment the
value of a money rent, even though it should be stipulated to be paid, not
in such a quantity of coined money of such a denomination (in so many pounds