Monetae cudendae ratio ("Treatise on Coin") and "Modus cudendi monetam" ("The Way to Strike Coin"). He made these the basis of a report which he presented to the Prussian Diet at Grudziądz (Graudenz) in 1522; Copernicus' friend Tiedemann Giese accompanied him on the trip to Graudenz. For the 1528 Prussian Diet, Copernicus wrote an expanded version of this paper, "Monetae cudendae ratio", setting forth a general theory of money. In the paper, Copernicus postulated the principle that "bad money drives out good", which later came to be referred to as Gresham's Law after a later describer, Sir Thomas Gresham. This phenomenon had been
Say's law real shocks cause recessions and that the market responds efficiently to these real economic shocks. Paul Krugman dismisses Say's law as, "at best, a useless tautology when individuals have the option of accumulating money rather than purchasing real goods and services". It is not easy to say what exactly Say's law says about the role of money apart from the claim that recession is not caused by lack of money. The phrase "products are paid for with products" is taken to mean that Say has a barter model of money; contrast with circuitist and post-Keynesian monetary theory. One can read