I was just reading someone saying that the dollar, being fiat currency, was a Ponzi scheme, just like cryptocurrency. Not so. There is a crucial difference. First, though: cryptocurrency is much like a Ponzi scheme (using the term loosely, as a way to sell something worthless to people because they hope to resell it some other sucker later) . When you own a bitcoin, that doesn’t obligate anyone to accept it as payment. You can sell it if someone wants to buy it, but nobody has to buy it, or to pay any particular price. There is not even a moral obligation or an implicit promise: it is entirely Buyer Beware. If we knew the world would end 5 years from today, everybody would know that bitcoin would be worthless 4 years from today, so its price would have to be zero then, which means nobody would want to hold it 3 years from today, which means, following the chain, nobody would want to hold it today. You only hold it to sell it somebody else.