Markets work best when there's lots of information available and a historical track record to go on; they excel at predicting things like horse races, election outcomes, and box-office results. But they're bad at predicting things like who will be the next Supreme Court nominee, as that depends on the whim of the president.

Political risk is hard to manage because so much comes down to the personal choices of policymakers, whether prime ministers or heads of central banks.

This intelligence, or what I'll call "the wisdom of crowds," is at work in the world in many different guises. It's the reason the Internet search engine Google can scan a billion Web pages and find the one page that has the exact piece of information you were looking for. It's the reason it's so hard to make money betting on NFL games, and it helps explain why, for the past fifteen years, a few hundred amateur traders in the middle of Iowa have done a better job of predicting election results than Gallup polls have.

The problem is that groups are only smart when the people in them are as independent as possible. This is the paradox of the wisdom of crowds.

In confusing stock options with ownership, corporations confuse trappings with substance.

In effect, dividing your attention means that neither (or none) of the things you're working on is really getting the full effect of your intelligence, and that it in the end takes you longer than it would if you did one thing at a time.

Businesses that have gone through an episode of hyperinflation become understandably alert to the threat of it: at the first hint of inflation, they're likely to increase prices, since they've learned that if they don't, and inflation hits, their businesses will be wrecked.