In order to work with perfection as a standard for deferred payments, the article chosen as that standard should place both debtors and creditors in exactly the same absolute, and the same relative, position to each other at the end of a contract that they occupied at its beginning; this implies that the chosen article should maintain the same exchange value in relation to goods, rents, and the wages of labour at the end as at the beginning of the contract, and it implies that the borrower and lender should preserve the same relative position as regards their fellow producers and consumers at the later as at the earlier point of time, and that they have not changed this relation, one at the loss of the other. This makes demands which any article that can be suggested as a standard cannot satisfy. And yet it is a practical necessity of society that some one article should in fact be selected as the standard. The business world has thus been forced to find some commodity which--while admittedly never capable of perfection--provides more nearly than anything else all the essentials of a desirable standard. The causes which may bring about changes in the relations between goods and labor, on the one side, and the standard, on the other, are various. We may, for instance, compare wheat with the existing gold standard. The quantity of gold for which the wheat will exchange is its price. As wheat falls in value relatively to gold, it exchanges for less gold, that is, its price falls; or, _vice versa_, gold exchanges for more wheat, and relatively to wheat gold has risen. As one goes up, the other term in the ratio necessarily goes down; just as certainly as a rise in one end of a plank balanced on a log necessitates a fall in the other end of the plank. Therefore, changes in prices can be caused by forces affecting either the gold side or the wheat side of the ratio; by forces affecting either the money standard or the goods compared with that standard. Consequences of importance follow from this explanation. First suppose that commodities and labor remain unchanged in their production and reward, respectively; then, anything affecting the supply of and demand for gold will affect in general the value of gold in comparison with goods and labor. Or, second, if we suppose an equilibrium between the demand for and supply of gold, then, prices and wages can be affected also by anything affecting the cost of obtaining goods or labor. It is one-sided to look for changes in prices solely from causes touching gold, or one term of the price ratio. If, however, it should be desired that prices should remain stationary, then this can be brought about only by finding for the standard an article that would automatically move in extent, and in the proper compensating direction, so as to meet any changes in value arising not only from causes affecting itself, but also from causes affecting labor and the vast number of goods that may be quoted in price.