been thinking - today we are currently using a system by the central bank giving governments unlimited supply of money that cannot be sustained.
say everything is shifting back to gold / silver.
today gold and silver is currently a finite limited supply on earth
what happens when we become a space civ in the next 10-100 years when we harvest comets which pretty much give us an endless supply of gold /silver other oras?
aren't we back into the same system to which the value of gold & silver is pretty must as limited to the vast amount of space devaluing its worth.
is crypto the only possible way?
The same reason any currency has existed throughout history: Perceived value.
Again.. even a fiat currency (that which is not backed by commodity, and has no intrinsic value) can work very well, but it can't be controlled behind closed doors, the way our current fiat currency is by the Fed. If you look into Lincoln's administration and his real goal of protecting the Union's currency from central banking (also the reason he was assassinated, and likely JFK as well), and thus protecting the nation from having their wealth syphoned from them by the vampiric banks, you'll find the original assertion to be true.
Trading sticks, coffee beans, gold and silver, or pieces of paper: It doesn't matter what form the currency takes (although I'm definitely partial to using a commodity with intrinsic value because it's much harder to counterfeit), because the value is in its potential to create wealth, not in its immediate utility.