I disagree with that definition of money. I don't think it actually defines what money is or what it does. I think that if you want to think of money in terms o

I disagree with that definition of money. I don't think it actually defines what money is or what it does. I think that if you want to think of money in terms of "value" that rather than a "store" of value, it is a "record" of value. If you want to think of it as a unit of account, it has to be a state unit of account in order to actually function as money. And finally I think that the function of money as a medium of exchange is actually a side effect; that is to say that money is the most liquid asset because it is created by an obligation in common to all citizens of a sovereign entity. As such, it is the most likely medium of exchange because it is universally accepted. However, anything can be a medium of exchange. Hot rocks can be used to heat a room, but you wouldn't call a pile of hot rocks a heater. In the same way, virtually anything can be a medium of exchange, but money (by virtue of being created by the imposition of a tax liability) is the most effective medium of exchange. My definition of money is: a credit that can be used to extinguish a tax liability imposed by a sovereign. Everything else is a commodity.