The history of finance is partly the history of a struggle for a stable, secure way to measure value. And, like any quest for certainty in our unpredictable world, it was doomed to failure. The latest financial crisis powerfully highlights this vulnerability, as it destroys any sense that we can put an accurate price on assets. Most people are convinced this shortcoming is inherent in the financial system. But uncertainties about value also expose deep problems in the political order.

In the past, metallic money provided an inconvenient and unsatisfactory solution to the question of value. It was inconvenient because gold was awkward for everyday transactions, and silver had too little value for major transfers.