Gresham's law commonly states: "Bad money drives out good." This law applies specifically when there are two forms of commodity money in circulation which are required by legal-tender laws to be accepted as having similar face values for economic transactions. Gresham's law is named after Sir Thomas Gresham (1519 – 1579), an English financier during the Tudor dynasty. The terms "good" and "bad" money are used in a technical, non-literal sense, and with regard to exchange values imposed by legal-tender legislation, as follows: