The market can quickly seize up. Prices don't adjust in a smooth continuous fashion, but instead abruptly reconfigure themselves, like the earth's cr… - David Orrell

Adam Smith's invisible hand does exist, but as an emergent property of a complex system. It has a fuzzy tendency to reduce big price discrepancies, but it acts in a rather haphazard way.

There is something intrinsically upside down and counter-intuitive in the relationship between money and happiness.

It has become increasingly evident, at least among those who aren't currency traders or true believers in the optimality of free markets, that it would be nice if this system could calm down a touch. One option is the Tobin tax, which would impose a tax of around 0.1 percent on currency trades, and act as a kind of damper on speculation.