Pensions aren't a Ponzi scheme. They just need to be calibrated that the years of pay-in and years of pay-out are balanced as to the ratio of the people in the

Pensions aren't a Ponzi scheme. They just need to be calibrated that the years of pay-in and years of pay-out are balanced as to the ratio of the people in the age cohorts. If you have 10 people paying in for 40 years and only 2 people receiving pay out for 10 years then the system is cheap.