Your point was that a fix-money-supply system is logically provable to be inherently unstable. Have we moved the goal post?
I don't quite understand what you mean. Anyway, you should keep in mind that if you want to logically disprove something you should yourself use logic but not refer to examples. Regarding your examples themselves, the Italian Renaissance cities are irrelevant as such since their economies are not sustainable on their own at all, in the first place. They were basically bankers and traders (read resellers). Without the rest of the world, they would quickly die out in a matter of months if not weeks. And which book are you talking about?
The producer-consumer example was my invention, just in case
Sorry, you're the one who has to prove that a fixed-money-supply economy is inherently unstable, since that was your assertion. I only have to provide counter-examples.
I am not asserting the stability of anything, since there are so many factors, that you can't guarantee stability, without looking at all of them. But I'm proving that fixed-money-supply systems are not inherently unstable by giving you two counter-examples (Renaissance city states and 3 centuries near the end of Imperial China.)
Trade was only one of many supporting factors for the Renaissance economy. Every economy has them. I suppose you're going to say that if a Medieval crop economy was subject to destruction by climate change, it would prove that fixed-supply-money is inherently unstable?
Or that the economy was no example of a stable, fixed-money-supply system?
You still have not addressed the core issue with your model, that having only actors who must increase their savings will naturally not work with a fixed money supply, so that the model was unrealistic and actually could be argued to have been chosen for its conclusions
I assume that all other actors ain't relevant. If you disagree, explain how they should be
See my original statement. I guess I'll just have to keep waiting.
That fixed-money-supply is unstable is an establishment-promoted myth that has become something of an orthodoxy today, in a world where the 'top' mainstream economists are essentially bought off by the establishment (that is, surely blind on purpose unless they are so obtuse as to miss the elephant in the room.)
Talk is cheap, show me how it is actually sustainable
In this case, I'll stick to cheap talk. Thank you very much.