Most people are highly optimistic most of the time.

That's one of the real dangers of leader selection in many organizations: leaders are selected for overconfidence.

We know that the French are very different from the Americans in their satisfaction with life. They're much less satisfied. Americans are pretty high up there, while the French are quite low - the world champions in life satisfaction are actually the Danes.

Clearly, the decision-making that we rely on in society is fallible. It's highly fallible, and we should know that.

A general “law of least effort” applies to cognitive as well as physical exertion. The law asserts that if there are several ways of achieving the same goal, people will eventually gravitate to the least demanding course of action. In the economy of action, effort is a cost, and the acquisition of skill is driven by the balance of benefits and costs. Laziness is built deep into our nature.

People have little idea, by and large, of the investment world. They are convinced they have an advantage.

The planning fallacy is that you make a plan, which is usually a best-case scenario. Then you assume that the outcome will follow your plan, even when you should know better.