"You know, back in the forty-niner days, every gold mining town in California had a nerd with a scale," Avi says. "The assayer. He sat in an office all day. Scary-looking rednecks came in with pouches of gold dust. The nerd weighed them, checked them for purity, told them what the stuff was worth. Basically, the assayer’s scale was the exchange point—the place where this mineral, this dirt from the ground, became money that would be recognized as such in any bank or marketplace in the world, from San Francisco to London to Beijing. Because of the nerd’s special knowledge, he could put his imprimatur on dirt and make it money. Just like we have the power to turn bits into money.