melting. Palestinian economist Adel Zagha also attributes a similar concept to medieval Islamic thinker Al-Maqrizi, who offered, claims Zagha, a close approximation to what would become known as Gresham's law centuries later. In the 14th century it was noted by Nicole Oresme , 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. Johannes de Strigys, an agent of Ludovico III Gonzaga, Marquis of Mantua in Venice, wrote in a June 1472 report ("that the bad money will chase out the good"). In the year that Gresham was born, 1519, it was described by Nicolaus Copernicus in a treatise called : "bad (debased) coinage drives good (un-debased) coinage out of circulation". Copernicus was aware of the practice of exchanging bad coins for good ones and melting down the latter or sending them abroad, and he seems to have drawn up some notes on this subject while he was at Olsztyn in 1519. He made them the basis of a report which he presented to the Prussian Diet held in 1522, attending the session with his friend Tiedemann Giese to represent his chapter. Copernicus's was an enlarged, Latin version of that report, setting forth a general theory of money for the 1528 diet. He also formulated a version of the quantity theory of money. For this reason, it is occasionally known as the Gresham–Copernicus law. Sir Thomas Gresham, a 16th century financial agent of the English Crown in the city of Antwerp, was one in a long series of proponents of the law, which he did to explain to Queen Elizabeth I what was happening to the English shilling. Her father, Henry VIII, had replaced 40% of the silver in the coin with base metals, to increase the government's income without raising taxes. Astute English merchants and ordinary subjects saved the good shillings from pure silver and circulated the bad ones. Hence, the bad money would be used whenever possible, and the good coinage would be saved and disappear from circulation. According to the economist George Selgin in his paper "Gresham's Law": Gresham made his observations of good and bad money while in the service of Queen Elizabeth, with respect only to the observed poor quality of British coinage. Earlier monarchs, Henry VIII and Edward VI, had forced the people to accept debased coinage by means of legal