In a rising market, enough of your bad ideas will pay off so that you'll never learn that you should have fewer ideas.

Many ideas happen to us. We have intuition, we have feeling, we have emotion, all of that happens, we don't decide to do it. We don't control it.

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

When you analyze happiness, it turns out that the way you spend your time is extremely important.

There are domains in which expertise is not possible. Stock picking is a good example. And in long-term political strategic forecasting, it's been shown that experts are just not better than a dice-throwing monkey.

Intuitive diagnosis is reliable when people have a lot of relevant feedback. But people are very often willing to make intuitive diagnoses even when they're very likely to be wrong.

Many people will admit that they made a mistake [putting money in dot-coms or telecoms at their peak] But that doesn’t mean that they’ve changed their mind about anything in particular. It doesn’t mean that they are now able to avoid that mistake.