[magicsmoke]

This was a really enjoyable read and actually helped plugged a few gaps I got from Graeber's work. I personally think his model for where money originated is very solid. Early human tribes work on emotional kinship ties and obligations within the family without a need to precisely account for debts. Money first appeared with city-states as standardized clay tokens used to account for grain taxes owed to the state. Give grain to the city or provide labor and services, get token, give token to tax collector on tax day to keep your city-assigned plot of farmland. But after this point in his book he jumps straight to how gold currency appeared with the rise in warfare in ancient Mesopotamia, but doesn't really give a good explanation why.

Based on what I got from this post, humans are evolutionarily wired to like shiny things, and this gives us a competitive advantage. Instead of lazying around to enjoy the sunset after a good harvest, our ancestors would have used the time to make elaborate collectables for its artistic qualities. Despite collectables not being something you can eat or live in, they happen to be a good insurance mechanism during hard times. Other tribes, though untrusting and hostile, also like shiny things and will share their food with you for collectables during emergencies where you need to depend on the kindness of strangers, turning them into a way to store the value of the leisure time used to create them. I wouldn't call this currency because collectables have no standardized value, its value being entirely subjective based on artistic preferences. One hunter might really like the color of your beads and give you two pheasants. Another might only give you half, but will give you three for your ivory comb instead. But this system is enough to sustain basic barter circles between foreign tribes and account for social obligations over time.

This evolutionary tendency to like shiny collectables combined with standardized states is what I think creates our first metallic coins. King Croesus of Lydia is facing a major war crisis as the ancient near east enters an age of chaos and decides to hire foreign mercenaries. He can't pay them with standardized tax tokens since they aren't his citizens to tax. He can't negotiate a tribute with their leader in luxury goods and jewelry because they're ragtags gathered from all over the land with no single leader. What he can do is melt down his golden collectable statues, divide them into standard units reminiscent of existing tax tokens, stamp them with his symbol, give each individual soldier a coin for every battle they fight, and appeal to our inherent love for shiny things. And so the first gold coin based on the existing idea of clay tax tokens is born.

[lasagnaphil]

Graeber clearly explained the process of how gold currency appeared in his book (I recommend you to reread Chapter 8: The Axial Age for this). It’s because states needed some convenient medium to provide resources for the military to continue its conquests, and that was precisely what the military was already pillaging from its conquered territory: luxury items made of gold. So the state had to find a way to enforce people to sell other important commodities (such as food and equipment) in exchange for gold, and that made the state to enforce gold coins as a currency in areas near conquests.

You’re right that the social/cultural value associated with those luxury gold collectibles is an important part of the story. But I don’t think you need any other weird evolutionary argument in addition to Graeber’s view to complete the full picture.

[magicsmoke]

The state could already force people under their control to sell commodities to their soldiers for clay tokens. Why switch to gold, a much more difficult resource to obtain and produce coinage with? Was clay suddenly no longer convenient for some handwavey reason because we're now in the Axial Age, despite being used for centuries before? That's the gap in Graebers book that I don't think he covered adequately.

The reason was because now the various city states needed a way to convince people outside their jurisdiction to also provide goods and services for their wars, and those people could not be cowed into using clay. Clay only works within a states jurisdiction because they could punish counterfeits and ensure it's value among subjects as a tax credit to the state. Outside a state's jurisdiction, foreign soldiers have no guarantee that those clay tokens will continue to be a secure store of value. What if the state you were fighting for collapsed tomorrow? Now their tax credits are worthless. Gold, on the other hand, holds it's value because people like shiny things regardless of which king is stamped on it. But because the gold is issued by a state with their tendency for standardization, now your gold trinkets come in nice standardized units instead of a random assortment of jewelry, what gold would have been used for previously.

[ethn]

Graeber’s model is refuted by the existence of pre-fiat currencies, the Wampum, the Chinese copper cowrie, and Bitcoin. Where Bitcoin is a currency but just deflationary like gold. Optimal currencies of course are inflationary or stable [1].

[1] This is a simplification, the real optimal rate of inflation is really -0.8% as shown in the seminal paper The Optimum Quantity of Money.