The idea behind the Ponzi scheme is fairly straightforward, and exploits the basic human tendency towards greed. The scheme then perpetuates itself using envy. Although there are variations, here is a classic scenario:
However, the catch is that at some point in time the scheme will vanish, typically at a point where a "critical mass" of capital has been achieved, and the operators disappear taking all of the capital amassed with them. A sad aspect of this is that typically all of those who actually made a "profit" at an earlier stage of the scheme will have (voluntarily) re-invested that money back in, so they lose it anyway.
A common variation involves a smaller return for a short-term investment (say 10% over 30 days), but a fantastic return for a longer investment (say 200% after six months). Once the intial trust has been achieved after making the shorter term gain, people are far more likely to leave their funds for this longer period. This naturally gives the operators more time to plan their disappearance.
It has been suggested that some state pension schemes, e.g. the U.S. Social Security and the U.K. State pension schemes bear disturbing resemblances to Ponzi schemes in their mode of financing. This is because benefits are paid from taxes currently being collected, rather than from the taxes previously paid by the current beneficiaries. This also explains why the aging of the Baby Boomer generation presents a threat to the U.S. Social Security system: as more of the Baby Boomers retire, there will be more people collecting social security benefits than there will be workers paying taxes for social security benefits. However, critics of this view state that the balance income and outgoings from Social Security is sustainable because the returns from Social Security are not high enough to cause the system to run out of money.
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Are state pensions a Ponzi scheme?