Yes, money is an illusion. No, the economic system isn't a Ponzi scheme, which would mean that later arrivals to the system would fund the earlier arrivals. If you would trouble yourself to do the actual work of learning Modern Monetary Theory, and not simply responding with a knee-jerk answer repeating your fondly-held beliefs, you would find out that Congress creates the currency every time they pass an appropriations bill. It's new money every time. They don't get funds from the later arrivals in the system to pay off the earlier arrivals. Please try learning something new. You'll be glad you did.