Alan Greenspan chose the perfect moment to release his memoirs: the day before a high-stakes Federal Reserve policy meeting in the middle of a financial market crisis. Even the title of his book, The Age of Turbulence, looks uncannily - if not uncharacteristically - prescient.

The turbulence to which Mr Greenspan refers in the title has two meanings: the wrenching change driven by the dynamic force of global capitalism and the bouts of dysfunction that periodically afflict the market mechanism that lies at its heart.