The modern conception of money is that something is the a good of exchange and a good of account. I would argue both of those have been invented independently both in various decentralized ways and by a state.

You can also keep accounts in your head. The concept stays the same if you write it down or not.

If the notes you are circulation are IOUs for that good then that does not change the underlying concept.

> Maybe I misunderstand, but it's not the whole point that markets deliver better solutions for everybody that any kind of central planning?

Markets come about as soon as you have property rights. Property rights come about in many ways (I have other comments in this thread making this point).

When you of course go impose a property rights solution on a society then that is of course a form of central planning.

So I would say again, you can have both, you can central plan a market, but not all markets are centrally planed.