Government and private retirement strategies both rely on cash transfers from younger workers. In a government system, the younger workers pay taxes which are transferred to retirees. In a private retirement system, younger workers are the purchasing counterparties as retirees sell off their investments.

Retirement financing in general relies on future economic growth for future cashflow. That said, you don't necessarily need a growing population to make it work. If the population declines 15%, but the average worker's productivity goes up 20% during that time, you still come out ahead.

>Government and private retirement strategies both rely on cash transfers from younger workers. In a government system, the younger workers pay taxes which are transferred to retirees. In a private retirement system, younger workers are the purchasing counterparties as retirees sell off their investments.

The core unit of the economy is not cash, it's value. Saving roughly corresponds to avoiding consumption and preserving value; in a very basic economy, this would take the form of e.g. preserving grain in a granary rather than eating it all. People or government savings systems that save for retirement are then able to consume the value they saved when they retire; they don't require any value transfer from the working population.

In a society that wishes to support people who are not producing value, the people who are producing value will need to overproduce.

Whether you measure the overage in units of lifetime granaries, or running annual surpluses, is primarily an accounting choice.

As a practical matter, it's impossible for one farmer to save up enough food to span their entire retirement. Storage is an expense, and food goes bad eventually. The concept of a retirement is only possible in a society that transacts value regularly.

Yeah but we have money that can be stored and anyone that is old and have reserves of money will be treated and get food etc.

Society doesn’t reward you based on the value you produce but based on how much fictional currency you have. This could be entirely granted to you for example in a a lottery and you never produced anything of value.

Money spoils (aka inflation) just as much as food does. To maintain the value of your money you have to actively utilize it in the economy by investing it. This is not a flaw. It is necessary to keep the economy running. Otherwise we would see Scrooge McDuck in real life.

This is why we have bank accounts and index funds.

You can't store medical workers in a silo for later. That's the big problem. Older people don't need to eat more but they do need more attention from nurses and doctors.

You'd still need someone to sell that 20% more product (or service) your worker is producing and with 15% less people your entire market has just shrunk.

That money is worthless if it is not backed by a young labor force that can produce what the pensioners need. There are not many things that you can buy during your 30s and keep using in your 80s.

Think of a reverse Corona virus that only kills the young. Retirees have lots of money but the shops and factories are closed.

But then our lifespans are getting longer and longer so we might be able/doomed to work forever and not need that pension.

The system was obviously designed for a "reasonable" amount of retirement from 5 to 10 years. Nowadays everyone is exceeding that despite a raised retirement age.

The key is who saves/invests the most and they will have access. This is how it works with everything in capitalism and this is the only efficient way we know of distributing resources.

The boomers will be dead long before the system shocks itself. Probably the tail end of Gen Xers or Millenials that will get royally screwed, if I had to guess.