How to refute Friedman's claim that social security is the biggest Ponzi scheme in history?

There is no need to refute it, let's see how you understand Ponzi scheme. The essence of Ponzi scheme is to borrow new debts to repay old debts, and so is its social security system, realizing pay-as-you-go system. A social security fee is actually used by the state to invest in construction. The social security that these people receive is actually part of the social security that the next part of people pay.

But there are two points worth noting:

1. The social security system in this country is covered by financial funds. Once there is any problem, you can support it with financial funds. In the Ponzi scheme, Ponzi didn't have the money. He can escape at any time, but the country can't escape at any time. It is credible.

2. If the cumulative social security system is adopted, this problem will not exist.