Thank you for the link. It’s very interesting. I haven’t gotten that far yet in the paper I am taking a pause before going into sparse merkle trees. I suspect the specific details will be different but there is an aspect of this that reminds me of ecash. In that the money has value (y can accept x’s debt as money from z only if x is trust worthy) (I would only accept your ecash token as money if I trust the mint that gave you the token to follow through and pay me when I exchange the token back) there is a similar dynamic with the ecash mints. So I’m wondering if this doesn’t result in a similar system in practice if everyone ran their own ecash mint. Where you could bring your bitcoin to me, I would issue you a token IOU for the Bitcoin back (debt) back and you use the debt (IOU) as money. The specifics of ecash have parts for privacy that I suspect won’t be in this.

The specific idea that money is trust, I find very interesting. I will be mulling that one over for some time.