Mental effort, I would argue, is relatively rare. Most of the time we coast.

Courage is willingness to take the risk once you know the odds. Optimistic overconfidence means you are taking the risk because you don't know the odds. It's a big difference.

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.

Nothing in life is quite as important as you think it is while you're thinking about it.

We were required to predict a soldier's performance in officer training and in combat, but we did so by evaluating his behavior over one hour in an artificial situation. This was a perfect instance of a general rule that I call WYSIATI, "What you see is all there is." We had made up a story from the little we knew but had no way to allow for what we did not know about the individual's future, which was almost everything that would actually matter. When you know as little as we did, you should not make extreme predictions like "He will be a star."

The concept of happiness has to be reorganised.

It was always assumed I would be a professor. I grew up thinking it.