Free Debt by David Graeber

political authority which minted the coin; on the other side is “tails”—the precise specification of the amount the coin is worth as payment in exchange. One side reminds us that states underwrite currencies and the money is originally a relation between persons in society, a token perhaps. The other reveals the coin as a thing, capable of entering into definite relations with other things. 1
    Clearly, money was not invented to overcome the inconveniences of barter between neighbors—since neighbors would have no reason to engage in barter in the first place. Still, a system of pure credit money would have serious inconveniences as well. Credit money is based on trust, and in competitive markets, trust itself becomes a scarce commodity. This is particularly true of dealings between strangers. Within the Roman empire, a silver coin stamped with the image of Tiberius might have circulated at a value considerably higher than the value of the silver it contained. Ancient coins invariably circulated at a value higher than their metal content. 2 This was largely because Tiberius’s government was willing to accept them at face value. However, thePersian government probably wasn’t, and the Mauryan and Chinese governments certainly weren’t. Very large numbers of Roman gold and silver coins did end up in India and even China; this is presumably the main reason that they were made of gold and silver to begin with.
    What’s true for a vast empire like Rome or China is obviously all the more true for a Sumerian or Greek city-state, let alone anyone operating within the kind of broken checkerboard of kingdoms, towns, and tiny principalities that prevailed in most of Medieval Europe or India. As I’ve pointed out, often what was inside and what was outside were not especially clear. Within a community—a town, a city, a guild or religious society—pretty much anything could function as money, provided everyone knew there was
someone
willing to accept it to cancel out a debt. To offer one particularly striking example, in certain cities in nineteenth-century Siam, small change consisted entirely of porcelain Chinese gaming counters—basically, the equivalent of poker chips—issued by local casinos. If one of these casinos went out of business or lost its license, its owners would have to send a crier through the streets banging a gong and announcing that anyone holding such chits had three days to redeem them. 3 For major transactions, of course, currency that was also acceptable outside the community (usually silver or gold again) was ordinarily employed.
    In a similar way, English shops, for many centuries, would issue their own wood or lead or leather token money. The practice was often technically illegal, but it continued until relatively recent times. Here is an example from the seventeenth century, by a certain Henry, who had a store at Stony Stratford, Buckinghamshire:

    This is clearly a case of the same principle: Henry would provide small change in the form of IOUs redeemable at his own store. As such, they might circulate broadly, at least among anyone who did regular business at that shop. But they were unlikely to travel very far from Stony Stratford—most tokens, in fact, never circulated more than a few blocks in any direction. For larger transactions, everyone, including Henry, expected money in a form that would be acceptable anywhere, including in Italy or France. 4
    Throughout most of history, even where we do find elaborate markets, we also find a complex jumble of different sorts of currency. Some of these may have originally emerged from barter between foreigners: the cacao money of Mesoamerica or salt money of Ethiopia are frequently cited examples. 5 Others arose from credit systems, or from arguments over what sort of goods should be acceptable to pay taxes or other debts. Such questions were often matters of endless contestation. One could often learn a lot about the balance of political forces