for those who say that bitcoin is a ponzi scheme, they do not understand what a ponzi scheme really is and they do not know bitcoin. they do not understand the concept of bitcoin and just open their mouths saying that bitcoin is a ponzi scheme. if only they understood that bitcoin is fundamentally different from a ponzi scheme, which has intrinsic value, many holders globally, and a trading market for it, then they would not think like that... but that's how it is, there are always people who don't like bitcoin and spread negative news about it, though it only shows how stupid they are.