>>> Other investors see X going up, and put money in X because it's going up. That's the start of a bubble - when people buy, not because they think the fundame

>>> Other investors see X going up, and put money in X because it's going up. That's the start of a bubble - when people buy, not because they think the fundamentals are good, but because it's going up and they don't want to miss out. So of course X goes up more because of all the new money coming in. That isn't just the start of the bubble, that's pretty much the definition - asset trading at the price that exceeds the asset's intrinsic value. If people are buying on speculation and not for it's utility, it's a bubble. >>> So, if my understanding of bubbles is correct, and if Bitcoin is going to be a typical bubble, the relevant question is, how much of the money invested in Bitcoin is borrowed? The amount of borrowed money used to purchase Bitcoin is certainly a lot greater than zero, which while not strictly a characteristic of a bubble, probably is a sign of nearing critical levels.