Sheets of five dollar notes go through a machine to receive a serial number and the seals of the U.S. Treasury and Federal Reserve at the Bureau of Engraving and Printing in Washington, D.C., U.S., on Tuesday, April 23, 2013. Stocks rallied amid growth in U.S. home sales, better-than-forecast earnings and speculation the European Central Bank will cut interest rates. U.S. equities recovered after briefly erasing gains following a false report of explosions at the White House. Photographer: Andrew Harrer/Bloomberg

钱处在4种不同状态时的影响

在《纸上承诺》(Paper Promises)这本书中,作者Philip Coggan指出,当钱(money)处在不同状态时,对经济会有不同的影响。