My old college roommate John R. Levine, who was a techie before anyone knew such creatures existed (let alone that they would rule the world), sends me a note about Bitcoin that confirms some of my own suspicions:

It occurs to me that part of the disconnect is that Bitcoin solved a major technical problem, one that people had been thinking about for about 20 years, and we nerds just can’t believe that it doesn’t also solve an economic problem. The technical problem is double spending–if I have some digital money, it’s easy enough to verify cryptographically that it’s real, but if I give it to you, how can you tell that I haven’t also given it to someone else? Until Bitcoin, the answer was to have a bank that knew which coins were valid, so you’d present my coin to the bank, which would check its database and if it’s valid, cancel it and give you a new

one. Bitcoin has its decentralized blockchain which is a very clever recasting of the problem so that the state of the “bank” is whatever the majority of bitcoin miners agree that it is. Getting enough of the miners to agree is known as the Byzantine Generals problem, and has a technical history of its own.

So with this breakthrough, we must have an economic breakthrough? We don’t? Well, then you just don’t understand/are in the pocket of the illuminati/whatever. If you belive that Bitcoin is a lot like paying for stuff with little bags of gold dust where every grain of dust has a publicly recorded serial number, well, then, uh.

My current guess is that the Bitcoin bubble will collapse when there is some bad news, e.g., a regulator demands registration of Bitcoin wallets, people try and cash out, and find that that while it’s easy to buy bitcoins, it’s much harder to find people willing to buy back nontrivial amounts, very hard to collect the sales proceeds, and completely impossible without revealing exactly who you are.