Right now, Cashu is being used as a money warehouse receipt. In history, it actually started that way when people deposited their gold and started to use the receipts as cash. The warehouse operators discovered when holding all that gold, they could issue bogus receipts, so long as they could cover redemptions.

Bills of exchange are a little bit different. If I couldn’t pay for something right away, I could issue a ‘promise to pay’ sometime in the future. This promise could be transferred by endorsing it. When the promise to pay came due, someone else could present the note, I could look at the string of signatures and say, ‘yep, that’s mine, I’ll pay’.

So both are treated as ‘cash’ but slightly different mechanisms. In the end, what is acceptable as ‘cash’ is in the eye of the beholder and whatever is used to facilitate a trade transaction.

Cashu can serve both use cases. The first, you’ll have mint operators that are in the business, the second is a more distributed case where everybody is their own mint. Who knows what will play out? I’m all in for the experimentation.