“If money is in essence transferable credit—rather than a commodity medium of exchange, as the academic economists insisted—then fundamentally different factors explain the economy’s demand for it. Meeting demand for commodities is a simple matter of ensuring a sufficient supply on the market. When it comes to transferable credit, however, volume alone is not enough: the creditworthiness of the issuer and the liquidity of the liability come into play. And both these factors are determined not technologically or physically but by the general levels of trust and confidence.”