Money is debt. Debt is a promise of something. You default when you can't keep your promise. If you promise gold or another country currency in exchange of you

Money is debt. Debt is a promise of something. You default when you can't keep your promise. If you promise gold or another country currency in exchange of yours, you can be in a position where you can't pay. If the only thing you promise is to accept your currency back as tax payment, you are never in a position where you can't pay. That inflation is low now is relevant because it invalidate the quantity of money view of inflation. We are in the middle of a huge "quantitative easing" and we don't see inflation. In fact we see the opposite. For instance, the ECB is injecting (if I remember properly, I didn't check) 80000 millions every month. So, the "common sense" view of inflation have been proved wrong again and again but, we continue hearing the same thing again and again.