The novels Going Postal and Making Money by Terry Pratchett actually use this as a plot device; they're comic Fantasy books that roughly parallel the invention of fiat currency.
It goes from people starting to use stamps instead of coins because they were lightweight and "backed by the government" for postage, to people slowly accepting notes of credit which are backed by gold in a vault, to people realizing that the notes aren't really backed by the gold, so much as they are by the city-state's entire economy and potential to do useful work.
"What is the value of a coin compared to that of the hand that holds it?"
It goes from people starting to use stamps instead of coins because they were lightweight and "backed by the government" for postage, to people slowly accepting notes of credit which are backed by gold in a vault, to people realizing that the notes aren't really backed by the gold, so much as they are by the city-state's entire economy and potential to do useful work.
"What is the value of a coin compared to that of the hand that holds it?"