be legitimate, to be on par with what we take for granted, which is currencies that are from governments? well, i think first of all it s going to be a long time before that happens. but what bitcoin needs is what any money in the world needs, and that is confidence of the people using it. the willingness of people to accept it. and that s been one of the great things about this bitcoin experiment is that it s sort of been this reminder that all money is in some ways now digital money. it just exists on ledgers on a computer. and the question of whether it is successful is a question of whether people have any confidence in it. indeed you re getting at the core point which you talk about at the beginning of the book money requires faith. people believe that this dollar or this coin will be able to be spent for something they want in the future so they have to pay. how is it the folks behind bitcoin have tried to inject that sort of faith in the bitcoin and why is it that they ve la