I'm pretty much agnostic on these issues, because I haven't really studied them as much as I'd like to. But I think the possibility of gold still playing an important role cannot be ruled out simply because it's "plain to see" that nobody uses gold as money anymore.
If the foundation of the credit system is "fiat money", what is the foundation of fiat money (say, dollar)? Is fiat money commodity? If it isn't, well that's one fundamental theorem of Marx's solution to the "riddle of money" that has to be given up. So was Fullarton right, as opposed to Marx?1 What determines the purchasing power of fiat money? I've heard various answers to this: the political and military dominance of the US, the promise of future accumulation, etc., but no book-length treatment of the issue (which it deserves, in my view). I'd appreciate any suggestions you might have.
On the other hand, I find some of the works by people who insist on the role of the money-commodity persuasive, as long as they don't shy away from empirical investigations. An example is the German economist Stefan Krüger. In an article published in 2009, he argues that there are four factors influencing the average prices (which he documents statistically): 1. the development of the productivity of labor within the national economy, 2. the development of the value-producing capability of the national productive labor in relationship to the universal labor on the world market, 3. the development of the productivity of labor in the world production of gold, 4. the changes in the relation of representation between national money and gold in the sense of the rate of inflation. He says that the so-called demonetization of gold served to increase the ability of central banks to regulate national currencies, but the ultimate frontiers to this ability are still determined, to a certain extent, by the value of gold.
BTW, to those who read German, Krüger has a new book which came out in January 2012. It's title is "The Political Economy of Money" (Politische Ökonomie des Geldes). With over 600 pages, it's another nice paperweight.
- 1. See Ch3 of Vol1: "The following passage from Fullarton shows the want of clearness on the pan of even the best writers on money, in their comprehension of its various functions: 'That, as far as concerns our domestic exchanges, all the monetary functions which are usually performed by gold and silver coins, may be performed as effectually by a circulation of inconvertible notes paying no value but that factitious and conventional value they derive from the law is a fact which admits, I conceive, of no denial. Value of this description may be made to answer all the purposes of intrinsic value, and supersede even the necessity for a standard, provided only the quantity of issues be kept under due limitation.' (Fullarton: “Regulation of Currencies,” London, 1845, p. 21.) Because the commodity that serves as money is capable of being replaced in circulation by mere symbols of value, therefore its functions as a measure of value and a standard of prices are declared to be superfluous!"
. Marx makes it clear that in currency (as "medium of circulation", i.e. cash), the money-commodity can be replaced by various tokens, coins, basically anything. Same goes for means of payment (i.e. promissory notes of all kinds, and credit money as a more developed form).



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No, it's foundation is still money, but now in the form of fiat money (inconvertible paper -- and electronic -- money) issued by the State and from which it can't detach itself (despite what the currency cranks who say banks can create money out of thin air think).
You don't think it's still money in the form of precious metals, do you?