Lower oil prices won't, by themselves, topple the mullahs in Iran. But it's significant that, historically, when oil prices have been low, Iranian reformers have been ascendant and radicals relatively subdued, and vice versa when prices have been high.

The fact that cognitive diversity matters does not mean that if you assemble a group of diverse but thoroughly uninformed people, their collective wisdom will be smarter than an expert's. But if you can assemble a diverse group of people who possess varying degrees of knowledge and insight, you're better off entrusting it with major decisions rather than leaving them in the hands of one or two people, no matter how smart those people are.

Developing countries often have hypertrophied bureaucracies, requiring businesses to deal with enormous amounts of red tape.

Lack of confidence, sometimes alternating with unrealistic dreams of heroic success, often leads to procrastination, and many studies suggest that procrastinators are self-handicappers: rather than risk failure, they prefer to create conditions that make success impossible, a reflex that of course creates a vicious cycle.

What corporations fear is the phenomenon now known, rather inelegantly, as 'commoditization.' What the term means is simply the conversion of the market for a given product into a commodity market, which is characterized by declining prices and profit margins, increasing competition, and lowered barriers to entry.

When Americans are asked to rank professions in terms of honesty and ethics, insurance agents routinely end up near the bottom of the list - somewhere between politicians and car salesmen. Generally, insurers are seen as clever hucksters who prey on insecurity and ignorance to sell people what they don't need at prices they shouldn't have to pay.

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.