Gresham's law. This is not an enactment but a law of political economy as expounded by Sir
Thomas Gresham, a former master of the British mint. It is that where there are two forms of
money the inferior or depreciated tends to drive the other from circulation owing to the hoarding
and exportation of the better form. As commonly stated, bad money drives out good.  Gresham's
words were: "When two sorts of coin are current in the same nation, of like value by denomination,
but not intrinsically, that which has the least value will be current and the other as much as
possible will be hoarded."