As I have stated earlier (see this post), a seller does not receive a payment when he receives an IOU. To claim otherwise would be illogical. "IOU" is an abbrevation for "I owe you"; it is synonymous with a "promise to pay (back) (later)".
I understand very well how this might cause confusion. And, as my statement is strictly unconventional, and for many even counterintuitive, it would be only natural if the ones I manage to confuse assumed that I, the writer, must ultimately be the one who is confused. The source of the confusion must be me, because the "facts" seem to be clear: money must exist and it is silly to suggest that money cannot pay for anything.
Perhaps I could be dismissed as a confused philosopher -- a logician who doesn't understand economics and the real world. But that would be wrong. Everything I say here is either derived from real world observations, or, tested against real world evidence.
This is science. This is economics.
Once we accept that where we used to see money is only IOUs, then many things start to make more sense. There's no more mysterious money that can be created "out of nothing". Paul Krugman's "debt is money we owe ourselves" loses all the meaning it might have previously had. The money which sloshes around the world is drained -- for good. (Was money yet another "flood myth"?) No more headlines like "ECB unleashes a wall of money" in The Financial Times. Note that here I'm only referring to respected sources, not to any fringe theory advocates who think that real money must assume material form.