The Internet has become a remarkable fount of economic and social innovation largely because it's been an archetypal level playing field, on which even sites with little or no money behind them - blogs, say, or Wikipedia - can become influential.

Defense contractors are able to reap tremendous profits while rarely confronting the risks for which those profits are supposed to be the reward.

The reason advertising is governed by fear, after all, is that most agencies rely on just a few clients to bring in the lion's share of their revenues.

Congressional Republicans themselves have vehemently defended the idea that preexisting conditions should not be used to deny people insurance.

The oil market is especially sensitive even to a hint of expansion or contraction in supply.

Campaigns fail if they waste resources courting voters who are unpersuadable or already persuaded. Their most urgent task is to find and persuade the few voters who are genuinely undecided and the larger number who are favorably disposed but need a push to actually vote.

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.