We develop a generic model of money and liquidity that identifies sources of liquidity bubbles and seignorage rents. We provide sufficient conditions under which a swap of monies leaves the equilibrium allocation and price system unchanged. We apply the equivalence result to the "Chicago Plan", cryptocurrencies, the Indian de-monetization experiment, and Central Bank Digital Currency (CBDC). In particular, we show why CBDC need not undermine financial stability.
Money creation monetary system inside money outside money equivalence CBDC Chicago Plan sovereign money