"In England the functions of a standardising commodity and of a medium of exchange are both alike performed by gold. Gold is applied to a vast number of purposes in the arts and sciences, and were it more abundant it would replace other metals in many more. Consequently a great number of easily accessible persons actually give a relatively high place to gold on their scales of preference, in virtue of its direct significance to them. It is established by custom (and, so far as that is possible, by law) as the universally accepted commodity; and at the same time it is used as the common measure in terms of which our estimates of all exchangeable things may be stated."