Debt, the First 5,000 Years is not the only text on this subject and it isn't canon. He's meaningfully wrong about a lot of things, and he's missing the 75,000

Debt, the First 5,000 Years is not the only text on this subject and it isn't canon. He's meaningfully wrong about a lot of things, and he's missing the 75,000 years prior to his story beginning completely. I strongly suggest reading some Szabo to fill that picture in. Shell money (ivory money sometimes) was a lot more money-like than Yap stones are.