Confidence is the philosopher's stone of economic expansion. In the abstract, it is limited only by the imagination of individuals who, when sufficiently inspired, can be persuaded to assign a value to anything. In practice, a loose supply of money will help prime the imagination. In the nineteenth century, paper currency provided the innovation and nobody was more innovative, in this regard, than Americans. In the United States, greenbacks were issued as promissory notes against the undeveloped wealth of the American frontier. The frontier was vast. Alas, man's faith was not. And when a rumor floated that a useless scrap of paper would no longer be redeemed for a useless bit of gold, people went for the gold, which held the psychological appeal of both precedence and substance. Confidence was shattered and many suffered.