conveniencies, and amusements. In proportion as this quantity is great or small, so are his real riches, his real weekly revenue. His weekly revenue is certainly not equal both to the guinea, and to what can be purchased with it, but only to one or other of those two equal values; and to the latter more properly than to the former, to the guinea’s worth rather than to the guinea.
If the pension of such a person was paid to him, not in gold, but in a weekly bill for a guinea, his revenue surely would not so properly consist in the piece of paper, as in what he could get for it. A guinea may be considered as a bill for a certain quantity of necessaries and conveniencies upon all the tradesmen in the neighbourhood. The revenue of the person to whom it is paid, does not so properly consist in the piece of gold, as in what he can get for it, or in what he can exchange it for. If it could be exchanged for nothing, it would, like a bill upon a bankrupt, be of no more value than the most useless piece of paper.
Though the weekly or yearly revenue of all the different inhabitants of any country, in the same manner, may be, and in reality frequently is paid to them in money, their real riches, however, the real weekly or yearly revenue of all of them taken together, must always be great or small in proportion to the quantity of consumable goods which they can all of them purchase with this money. The whole revenue of all of them taken together is evidently not equal to both the money and the consumable goods; but only to one or other of those two values, and to the latter more properly than to the former.
Though we frequently, therefore, express a person’s revenue by the metal pieces which are annually paid to him, it is because the amount of those pieces regulates the extent of his power of purchasing, or the value of the goods which he can annually afford to consume. We still consider his revenue as consisting in this power of purchasing or consuming, and not in the pieces which convey it.