Taxes solve the buy-in and the problem of getting everyone to collectively agree on which money to standardize on, but fundamentally any token which the issuer

Taxes solve the buy-in and the problem of getting everyone to collectively agree on which money to standardize on, but fundamentally any token which the issuer agrees to accept in exchange for a debt is "money". Forget about NCG. Suppose you move somewhere without any government. Heinlein ran through this example as a thought experiment in _Time Enough for Love_. You open up a general store. Nobody has any money to pay you, so whenever someone wants to buy something, they have to trade something. You can't set prices because there's no currency unit (numeraire) to set prices in. So what you do is you offer to let people buy things on credit, knowing that they will later have stuff to trade you to satisfy the debt. All this requires is a book to track debts. That leaves you having to haggle at time of repayment what that thing in the past they bought was worth, in terms of what they have to trade for it now. So, you as the owner print up "notes" and give them out to people, typically for larger projects, with contractual promise of repayment later. These can be called loans. They don't have to be for projects, though. You could give everyone some "notes" every month and keep track in a ledger that they owe you that back with interest, or maybe no interest if you think people using your notes will give you an advantage over your competition, the general store in the next valley over that everyone is sick of bartering with. Whatever the reason for handing out these "notes", you can then set all your prices in terms of the numeraire on these "notes" you hand out, so the person you loaned money to can buy stuff from you. The people you loan to can also buy stuff from other people using these "notes" as long as those other people also want to buy stuff from your general store. Maybe the loanee starts up a farm with the loan. As the farm produces food, they sell the food to other people, and maybe they accept the "notes" back as payment for the food. The loanee can use the "notes" they received from the food they sold to pay back their debt to your general store. With interest, of course. Trying to balance money supply with economic activity — and only the activity of people willing to use that type of money — is a challenge in such a small economy like that, with privately-issued currency. However, no taxes are necessary.