Cryptocurrencies have the advantage that they can be spent worldwide, instantaneously, with little friction, while most commodities require that you be physically present to exchange them. They're also significantly easier to store and more resistant to garden-variety theft, as long as they're secured by passphrases. But they exist in the uncanny valley of requiring electricity and Internet. It is fairly unlikely that the government collapses and yet you still retain always-on electricity and Internet. What will you use to pay the electric company, and how do you enforce the contract that they keep providing you power?
There's perhaps an interesting role for a digital cryptocurrency that does not require always-on connectivity, eg. something that can be carried over SneakerNet for local transactions, and then automatically syncs up with the global system when the community regains Internet connectivity. In actual conflict zones today, people seem to get intermittent electrical & Internet connectivity, eg. the electricity will come on for an hour a day with rolling blackouts, and then you try to get everything charged in that one hour. And there are enough solar installations out there that several communities are likely to retain significant power even in the event of a societal collapse. But current crypto's consensus mechanisms aren't built for intermittent connectivity: you'd need to build and design something that is eventually consistent, where a weeks-long fork does not result in two competing cryptocurrencies.
Are cigarettes really currency in this case? Aren't they more like one of many possible barter units? Can't you also price things in ramen packs in prison?
Similarly, I thought the sea shells thing had been sort of debunked. In that scale of society you don't need currency, you know the guy. David Graeber summarizes this rather intuitively. Why would you need to give a guy a sea shell in a "hunter gatherer group"? You're gonna see him every day of your life and everyone is gonna know/remember he owes you one. It would be like giving your sibling a sea shell because you did them a little favor or something. It doesn't actually happen that way because it would be a complete waste of time, just actually return the favor next time. I believe the sea shell thing is more like a gift, rather than a currency. Like you might give someone a flower to tell them you think they're swell. Presumably you think that because they helped you at some point. That doesn't make it currency. People just liked giving each other shells.
I think on most modern theories, currency really comes about from conquest. The idea is as you expand these informal IOUs are not enough. You don't want to have to lug around ramen packs or cigarettes. So at the point of a sword or w/e you say hey take this coin and give us food and then you honor the coin enough and people trust it, not because it's "fungible, tradable, generally-durable commodity that the bulk of society decides to accept as being worthwhile" but because if you don't accept it the government will kill you. And if you do accept it then not only will they not kill you but they'll give things back to you later, which you will end up being a positive incentive for everyone. Now instead of a presiding over a killing field you've created a market. But without the threat of the state, it is not coherent. That's what government is.
That's basically what it says on American money. "This note is legal tender for all debts, public and private". So sure a business can refuse you service, that's a separate issue. But if you have a debt in the United States and you try to give them US dollars and they refuse and say, no thanks actually we demand cigarettes - well now they are breaking the law, aka inviting the wrath of the state. So everyone uses dollars because the last thing anyone wants is to be in debt and think a pack of ramen is gonna work and they just get to say no thanks cigarettes for me please.
And of course, you also don't want to get impaled on a spike by a dude who looks suspiciously like that guy on the coin you probably should have taken.
The point is that they weren’t just used within a single group where everyone had access to more for the cost of only labor.
You actually see this on a small scale today in the functioning of many small communities, eg. you don't actually exchange currency to pay the host of a party, but you are expected to reciprocate and host sometimes yourself if you want to keep getting invited. There's a surprisingly large amount of these unpaid micro-transactions that happen, eg. my wife has gotten free childcare, free advice, free (used) furniture, free baby clothes, etc, all in the heart of Silicon Valley, because she reciprocates and also gives away her old furniture, baby toys, baby clothes, advice, introductions, childcare, etc. But when we have to pay the contractor for work on our house, we need dollars. When we buy a computer, we need dollars. When we buy all those goods that we give away new, we need dollars. That again reinforces the "credit is for people you know, currency is for people you don't" distinction.
Barter is used when a previous currency system collapses. The currency is no longer guaranteed to be accepted, so people want hard goods that they know they can use. But barter is an unstable equilibrium: as you mentioned, currency is just barter where one particular good becomes so widely accepted that people will take it not because they want it, but because it can be traded for other things that they want. There are reports of the Bosnian War [2] that described how alcohol and ammo quickly became pseudo-currencies because they were universally accepted and could easily be traded for what you actually needed.
Graeber isn't wrong, but as an anthropologist he over-indexes on the within-group interactions. There are lots of documented examples of currency emerging spontaneously from trade between groups where the groups all mutually decided that one type of object had value.
[1] https://news.ycombinator.com/item?id=49708431
[2] https://www.scribd.com/document/664716931/How-I-survived-a-y...
I'm not sure your in group/out group thing really holds up. I think of your credit/wife examples as not "credit" but something like basic reciprocity, closer to barter.
I think it's just a bit of blurring of terms. In my mind, bullets and ammo are just not currency in the same way a coin is. You can call it a "pseudo-currency" but the pseudo is kind of cheating.
I'm also not sure "There are lots of documented examples of currency emerging spontaneously from trade between groups where the groups all mutually decided that one type of object had value" disproves the point about violence/government. Can't I do the "pseudo" move back at you? What is the mechanism of the "mutual decision"? Would it be unlike the ones that lead to states? It sounds like everyone agrees something has value so we can have a dispute resolution mechanism. The implication being if you don't agree the other choice is violence? What if I say this "spontaneous collective of groups" is a "pseudo-government"?
Where would that leave us?
Kind of like how the local church might traditionally manage birth/death/land records, but that doesn't mean the documents are sacred or a religious observance.
Well I mean technically they are always for credit purposes, even if they are the "default/convenient payment method"? That's part of the advantage, but it's still credit. You get to spend and pay later. It wouldn't be a very good evaluation for credit purposes if it didn't work like credit? Or am I misunderstanding you?
It's just to say that "credit" isn't just about an in vs out group anymore than debt is. Or anymore than "currency" is? I'm not sure how the distinction you make helps clarify that question. The point is why would credit be for people you know, and currency for people you don't? Isn't credit just a particular agreement around said currency?
You don't need a government backed paper currency, you need a mint making precious metal coins. History has several examples like the mints at the Potosí silver mines or those by the East India Company that enabled trade without effective governments to back them up by just providing reliable coinage that spread to many other polities.
As long as there isn't some crazy inflationary force like colonizers arriving with an unlimited supply, we can use something as simple as beads or seashells for currency quite fine. It just means more labor overhead to create that currency in the first place.
Somalia operated on paper money valued at the cost of producing it
How something comes to be is distinct from how it is used.