"It is certain that all things appear incredible to us in proportion as they differ from known customs; but one who can judge aright will not wonder to find that, since their constitution differs so much from ours, their value of gold and silver should be measured by a very different standard; for since they have no use for money among themselves, but keep it as a provision against events which seldom happen, and between which there are generally long intervening intervals, they value it no farther than it deserves—that is, in proportion to its use. So that it is plain they must prefer iron either to gold or silver, for men can no more live without iron than without fire or water; but Nature has marked out no use for the other metals so essential as not easily to be dispensed with. The folly of men has enhanced the value of gold and silver because of their scarcity; whereas, on the contrary, it is their opinion that Nature, as an indulgent parent, has freely given us all the best things in great abundance, such as water and earth, but has laid up and hid from us the things that are vain and useless.