Intellectual-property rules are clearly necessary to spur innovation: if every invention could be stolen, or every new drug immediately copied, few people would invest in innovation. But too much protection can strangle competition and can limit what economists call 'incremental innovation' - innovations that build, in some way, on others.

If you work for Google or Apple, stock options give you a chance to share in the increasing value of the company. In the N.F.L., nothing like this happens; the players, though rich, are just working stiffs like the rest of us.

The stock market has an insidious effect on C.E.O.s' moods, because of its impact not just on their companies but on their own bank accounts.

Tough times have always lent themselves to nativist sentiments and closed-door policies. But in the case of highly skilled immigrants these policies are a recipe for stagnation.

In practice, downsizing is too often about cutting your work force while keeping your business the same, and doing so not by investments in productivity-enhancing technology, but by making people pull 80-hour weeks and bringing in temps to fill the gap.

Behavioral economists have shown that a sizable percentage of people are willing to pay real money to punish people who are taking from a common pot but not contributing to it. Just to insure that shirkers get what they deserve, we are prepared to make ourselves poorer.

Although oil is a commodity, it's still not a commodity like coffee, which, thank God, we will have with us always. At some point the oil will run out.