🔗 Gresham's Law

In economics, Gresham's law is a monetary principle stating that "bad money drives out good". For example, if there are two forms of commodity money in circulation, which are accepted by law as having similar face value, the more valuable commodity will gradually disappear from circulation.

The law was named in 1860 by Henry Dunning Macleod, after Sir Thomas Gresham (1519–1579), who was an English financier during the Tudor dynasty. However, the concept itself had been previously expressed by others, including by Aristophanes in his play The Frogs, which dates from around the end of the 5th century BC, in the 14th century by Nicole Oresme c. 1350, in his treatise On the Origin, Nature, Law, and Alterations of Money, and by jurist and historian Al-Maqrizi (1364–1442) in the Mamluk Empire; and in 1519 by Nicolaus Copernicus in a treatise called Monetae cudendae ratio For this reason, it is occasionally known as the Gresham–Copernicus' law.