[giantg2]

How is this a Ponzi Scheme ? "Currently working people help sustain retired people the same way retired people help the retired people when they were working and the same way young people will sustain the currently working people when they retire."

The only reason ponzi schemes fail is when they don't have enough fresh blood to pay out the prior investors. Your mention of population shrinkage after a baby boom is fairly similar.

"You can disagree with the idea but calling it a Ponzi scheme is incorrect."

Yes, it may operate similar to a ponzi scheme but cannot technically be called one. Usually the owner of the ponzi fund siphons off money for themselves, which is pretty similar to congress siphoning off social security for other pet programs. So I do agree with the sentiment, at least here in the US where the programs are expected to be insolvent in the coming decades.