@La_gar Capitalism is what happens when generations of thoughtlessness corrupt a good idea like, "hey, maybe I can carry some pieces of valuable metals around instead of a whole herd of goats to exchange for a nice warm blanket that I do not currently possess while these nights are getting nippy". Come to think of it, what we call Communism is also what happens when frustrated and often angry idealists don't catch the malice and selfishness behind the pursuit of any power, so just because a bunch of people say that wealth inequality won't be a problem anymore, that doesn't mean that the threat of violent physical force won't still be a problem, or that social clout won't still be something to trade on…equally corrupt. (Yes, yes, what laypeople call Communism is too authoritarian to truly qualify as what some academics define "communism" to be.)
So, for example, one issue in the world right now (and for decades before now) is that there actually IS enough food for everybody. It's just that the economic system has contrived famine during times of abundance, so if there's a huge glut in oranges or tomatoes (that is, an abundant harvest), then instead of putting in the effort to send that food to distributors who will give that food to people who don't have food…laborers bury what would have been perfectly delicious oranges or tomatoes, because there isn't the protocols or logistics in place for them to do the right thing, the system isn't built to allow anybody to do the right thing. Otherwise, the prices of oranges and tomatoes would, due to the glut, be re-sold at prices that is lower than the labour is worth, which is unsustainable in terms of a business. The Invisible Hands of determining value by balancing supply against demand never take into account the sustainability of something…if it's not a renewable resource, or if it's an overly abundant perishable resource. Fossil fuels shouldn't have been sold at an accessible enough price that we build so much of our civilizations around it, because its rarity would only increase and then what are we supposed to do with a civilization built upon the use of fossil fuels when there's no longer fossil fuels? Plastic shouldn't be ubiquitous and inescapable in the same civilization (indeed, in some of the same products) that plans for things to become obsolete, because it takes hundreds of years for it to not be shaped like itself anymore.
So…in your economic system, what is the "currency" through which activity flows held literally accountable to?
Traditional economics is held to the trust between people. If you want to trade a coin with the emperor's face on it for a delicious bowl of grilled snails, then the cook who has put in the work to grill and season those snails will only give it to you in exchange for the coin if they trust that they can exchange that coin later…for the favor that the snail-harvester does the cook for bringing those snails to them in the first place (and then some; a gift for their aunt who taught them how to cook, a bit to the metalsmith for a new grill, a bit of the value of that coin to the landowner for repairing the roof of the insula-apartment they rent, divide that coin into a pile of less valuable metals of equal value and maybe some of those go to some street urchins that the cook felt sorry for them not having any parents, whatever.)
The emperor is basically making a promise to the common people that whatever time or effort they take out of their lives and into contributing to society when they'd usually rather be doing something else, will be reimbursed. That's not a promise that the emperor can keep, between muggings, war economy, famines (like how can you exchange a coin for wheat that doesn't even exist?), invasion (like an enemy nation says, "now that we're here we'll tell you to stop using those coins, start using ours…or we'll kill you for sedition,") or maybe some wealthy foreign tourist does so much shopping in the market that gold becomes too common in that region (this actually happened). Or maybe a laborer has found what they truly love doing in life, and coincidentally it's something that society is willing to pay them regularly to do so it's not a matter of being compensated for when this person would "rather be doing something else".
But usually, it's going to be held together by trusting each other.
There are other things to hold the value to along with trust, such as the scarcity of a substance or object (such as precious metals, look at what Mansa Musa I of Mali did to Egypt while he was on vacation there), or the value put to labour and time (the job of grilling snails let's say is raised to $15 per hour, but somebody who has a more highly-valued skill such as predicting the future by looking at the entrails of a sacrificed owl can then charge clients $72 per hour for performing that service), I've also noticed for example where I live that communications service providers allow subscribers to exchange pre-paid minutes for things other than communicating over the phone through calls or texts (or to surf the internet on a specific broadband limit, as this bit of information technology is associated very closely with the evolution of the phone). Each purchase of pre-paid minutes comes with a rebate point that, if you collect enough of those, can be exchanged for things like stationery or an ice cream or any product from any business that has agreed to give their products away in exchange for deducting somebody else's prepaid minute rebate points. While this still requires use of the local currency to purchase prepaid minutes in the first place to get that sub/micro-economy system going, I think it's interesting to consider a currency of which the value is held to the ability to communicate or to share information.
So, I suppose…look at the nature of your society? What are the natural resources, or the material cultures? What needs to be done to keep the society together and trusting each other?
Because if the setting were somewhere that food forests grew naturally and the weather were perfect all the time, and nobody even accidentally edged in on the territory that had become a comfortable habit to another person and changed something there that the habitual person would rather they not have changed (such as chopped a favorite nearby fruit tree down to get at the fruits), or accidentally ate somebody else's pet, or wanted to organize extra attention and stuff to ritualize a rite of passage such as recognized adulthood or funeral, nobody needed to delegate tasks such as keeping apex predators away from all the children while their parents foraged for food…then nobody would own anything, because they wouldn't need anything, nobody would owe anybody else anything, nobody would need help with remembering who owes what to whom, and no boundaries or limits would need to be reinforced, no altercations would need to be resolved like a wergild or anything.
How far is your setting and cultures and the people in it, from this utopia? In what direction does that distance go?
Or maybe you are writing a utopia exactly as I described, in which case there would be no currency required.