Gold has been a central currency from about 600 BC down to the twentieth century. From Isaac Newton's recoinage of 1717 to the final closure of the Bretton Woods gold window by President Nixon, it was the pivot of the world exchange system. Gold reserves remain important to central banking. The role of gold in the world's exchange system has been hotly contested by leading economists like John Locke, David Hume and Maynard Keynes - who attacked gold - and Jacques Rueff. Nevertheless, the arguments in favour of gold, which includes the quantity theory of money, have remained scattered. With the assistance of the World Gold Council, Pickering & Chatto has collected the most important arguments in favour of gold, including such seminal works as David Ricardo's High Price of Bullion and W Stanley Jevons, Money and the Mechanism of Exchange.