[antiscam]

Bitcoin marketers invariably use formal analogies to suggest that Bitcoin isn't a scam. "The early adopters benefit just like in Google, so there can't be anything wrong with that" or "If Bitcoin is a pyramid scheme, then US dollars are as well."

The problem is that these analogies neglect all context and substance. Just because some schemes that benefit early adopters aren't scams doesn't mean that all such schemes aren't scams. Just because not everything called a "currency" isn't dishonest doesn't mean that this one isn't being marketed dishonestly and without regard to the people who will lose money as a result.

What's different between Bitcoin and gold? Bitcoin has very limited history, whereas gold has a much deeper history. Gold doesn't face existential security problems; Bitcoin has faced security compromises (such as an integer overflow in the block chain) even in its short history, and these compromises have had to be corrected using out-of-band mechanisms. The Bitcoin market is tiny, subject to market manipulation, and operates through unregulated and probably illegitimate exchanges. Finally, people buy gold without most people who own it spending a good chunk of their time promoting it dishonestly to others.