Summary: A few months back, we bought a tiny gold coin. The idea was to understand gold and its role in the history of money. That coin got us thinking about this really basic question: What is money? The question led us to Yap -- a tiny island in the middle of the Pacific Ocean, where for hundreds of years people used giant stone discs as a form of money. As it turns out, those stone discs say a lot about the meaning of money. If you don't believe us, just ask Milton Friedman.
