> how much money should be in the economy? How should it be created or destroyed?
Great questions.
Money is created when money is loaned out against collateral. Money is destroyed when the loan is repaid and the collateral returned. It's a natural process. The pressure on it is to have the supply of money match the value in the collateral.
> whoever has lisense to print money
Under a free banking system, anyone can print money. Of course, anyone printing money has to convince others that it has value. Did you know that anyone can print money today? We call them "IOUs", "checks", and more recently, "credit cards". We're all familiar with having to convince others that our IOUs, checks, and credit cards will be honored.
I'm not aware of any that managed to rule the world or collapse the economy.
> no answer
I just gave you one! I can only surmise you've been talking to the wrong people. May I suggest Milton Friedman's "Monetary History of the United States". It's tough sledding, but worth it if you really want to know.
> Is using a physical valuable substance as money, let's say gold, free market?
Of course. Are you familiar with the commodities marketplace? It's the same thing, but would you call that mercantilism? Shipping gold around to settle debts, however, is clumsy, expensive, and dangerous, hence the rise of trading receipts for the gold instead, and later those receipts turning into bank notes, and even later became electronic entries in a ledger.
> Do you want to have gold standard and fractional reserve banking?
That's how free banking worked in the United States. It's free market.
> they used to collapse all the time.
Not all the time, but banks did fail from time to time.
> That's why we invented central banks.
That was the public reason. The real reason was to inflate the money. As for collapse, now we have fewer bank failures, but when they do fail, it's a doozy (Great Depression, 2008, etc.). Also, did you notice that as of this month 9% of the money you had last year disappeared? You can thank our fiat money system for that.
I grew up in the Carter stagflation years, and learned to never keep more than pocket money around. It's all in things that aren't inflated into worthlessness by the central bank.
P.S. How do I know all this stuff? My dad spent the last years of his career as head of the finance department at a college. We had many long and happy conversations about how banks worked. It isn't an easy subject, but I wish more people could have such an experience.