@LаngLаngС I agree it would do better on Hermeneutics, but the type of argument allowed on each site is very different, so duplication between the sites isn't necessarily a bad thing.

@LаngLаngС I am not convinced I understand what you mean here, but if it is "We don't accept essay-style arguments, where people come up with their own conjectures, and use rhetoric to support it" then I agree. That's a reason for being here rather than other Q&A sites.

This answer quotes the Bible as a source, but not for something scientific but as evidence that people were using money at the time. Is that a valid source?

@gerrit It's a bad answer because the logic is "Abraham used money, and because his story is so old, I don't think 'barter' systems was ever really a thing." It's pretty evident that barter systems both were and still are a thing.

It also seems quite non-controversial to me to suggest that barter preceded money.

@fredsbend I agree it's a poor answer.

And evidently it is controversial to suggest that barter preceded money, because multiple prominent sources challenge this. Sometimes the most widely held beliefs are exactly the ones that need to be put to a thorough test.

@gerrit I flagged as "very low quality", so I guess I agree that quoting the Abraham story from the bible is not a relevant source on the topic.

@gerrit I have a hard time believing barter did not precede currency, but as I noted on Paul's answer, the semantics I mean here might be in play.

For example, I think some do not include services in barter, but as something else. I do, and I think many others would. A quid pro quo is so basic to human interaction and success as a species, even children understand it. "I will do this, and you will do that, and together we have a better outcome."

At this point I concede that I take it as a given that from that proceeds "I will give you this, if you will give me that."

Naturally, ancient humans produced what they needed for themselves. Considering these products as possessions (a unique behavior in the animal kingdom) that we have exclusive right to keep and use is not uniformly understood in all cultures, but the kernel of it is. With an understanding of possession, humans learned next to trade them.

This Graeber in Avery's answer seems to claim that a pure barter system never existed anywhere. That is a nuance that I think could be true. I surmise that if humans are smart enough to understand and respect possession, and intuitively understand quid pro quo, then the use of trade and means of trade arising together is interesting and sounds possible.

I don't know if even the word "system" is not subject to a semantic problem. How much "system" is there in a hunter-gather prehistoric band 100 members large?

Now how much trade do we expect it's members to have done? How much use for currency?

Is that barter when they did trade? (I say yes.) A barter system. (Uhhhh, not really.)

Now that I'm thinking out loud, what the hell is a barter system anyway? Is Graeber attacking a straw man? Can we possibly imagine any community with long-term success that has a defined and maybe even codified barter system, as opposed to a currency system?

Wouldn't the act of codifying barter trades (e.g. sheepskins are equal in worth to calfskins) make certain items into currency?

If (following my calf/sheep skins example) calf and sheep skins are equal in value, that is only a half step away from requiring merchants to accept them for their other goods. It seems like it would naturally arise in less than 1 generation that the people of such a system would accept sheep and calf skins out of convenience, knowing another will accept them. American fur trade put up animal skins as a de facto currency. People hoarded them like cash, and that period was only 250 years or so.

The real invention was the "note of ownership", where by being a holder of a sealed paper you were proven to have ownership of X number of skins. That is currency proper, in my definitions, whereas the skins by themselves are not quite, but pretty close.

So I guess I'd say true and complete currency is not consumed, and the substance of the currency itself (e.g. paper) is completely divorced from it's value.