corruption, and manipulation, precisely as it does not satisfy the criteria for a medium of exchange cited above. Specifically, prevailing fiat money is free-floating, and depending upon its supply market finds or sets a value to it that continues to change as the supply of money shifts with respect to the economy's demand. Increasing free-floating money supply with respect to needs of the economy reduces the quantity of the basket of the goods and services. It is not a unit or standard measure of wealth and so the manipulation impedes the market mechanism by setting or determining just prices. This leads to a situation where no value-related economic data is just or reliable. On the other hand, Chartalists claim that the ability to manipulate the value of fiat money is an advantage, in that fiscal stimulus is more easily available in times of economic crisis. Requisites needed Although the unit of account must be in some way related to the medium of exchange in use, e.g. ensuring coinage is in denominations of that unit, making accounting simpler to perform, it is more often the case that media of exchange have no natural relationship to that unit, and must be 'minted' as having that value. Further, there may be variances in quality of the underlying good which may not have fully agreed perceived value grading. The difference between the two functions becomes obvious when one considers the fact that coins were very often 'shaved.' Precious metal was removed from them, leaving them still useful as an identifiable coin in the marketplace, for a certain number of units in trade, but which no longer had the quantity of metal supplied by the coin's minter. It was observed as early as Oresme, Copernicus and then in 1558 by Sir Thomas Gresham, that "bad" money drives out "good" in any marketplace; (Gresham's Law states "Where legal tender laws exist, bad money drives out good money"). A more precise definition follows that: "A currency that is artificially overvalued by law will drive out of circulation a currency that is artificially undervalued by that law." Gresham's law is a specific application of the general law of price controls. A common explanation is that people will always keep the less adultered, less clipped, less filed, less trimmed coin, and offer the other in the marketplace for the full units for which it is marked. It is inevitably