Forgive me, but you do not have a decent handle on it. You possess a conformists understanding of money, and I think the condescending tone with which you have spoken to this gentleman is both inappropriate and unjustified. You don't seem to know what the fuck you are talking about.

@idealist had it correct. All money is debt. And it could never be paid back, because every time new money is printed and loaned to the governments of the world, there is interest attached. And where does the money to pay that interest come from? Nowhere. Because it doesn't exist. This is clearly what they were getting at, and I think you owe him or her an apology for the way you spoke to them. You can do better.