On Wall Street, fraudulent schemes tend to thrive during economic booms, and to blow up when times turn tough.

There are lots of people who believe there may be at least some genetic component to procrastination, and even if there isn't, it seems to be the case that procrastination habits are often set relatively early in life (that's certainly the case with me). But I also think that there's lots of evidence that external tools can help quite a bit in getting people to stop procrastinating.

Framing effects can be very influential, and to the degree that you can think of a task as close rather than distant, you're more likely to actually get it done.

Self-dealing, essentially, occurs when managers run companies to line their own pockets instead of those of the companies' owners. It's been a perennial problem in American capitalism and became a real dilemma when America moved toward a model in which corporations would be run by professional managers who had only small ownership stakes.

Auto repair, piloting, skiing, perhaps even management: these are skills that yield to application, hard work, and native talent. But forecasting an uncertain future and deciding the best course of action in the face of that future are much less likely to do so. And much of what we've seen so far suggests that a large group of diverse individuals will come up with better and more robust forecasts and make more intelligent decisions than even the most skilled "decision maker."

Wall Street has come a long way from the insider-dominated world that was blown apart by the Great Depression.

Bubbles and crashes are textbook examples of collective decision making gone wrong. In a bubble, all of the conditions that make groups intelligent - independence, diversity, private judgement-disappear.