To know whether you can trust a particular intuitive judgment, there are two questions you should ask: Is the environment in which the judgment is made sufficiently regular to enable predictions from the available evidence? The answer is yes for diagnosticians, no for stock pickers. Do the professionals have an adequate opportunity to learn the cues and the regularities? The answer here depends on the professionals' experience and on the quality and speed with which they discover their mistakes.

When people think of the outcomes of their decisions, they think much more short term than that. They think in terms of gains and losses.

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.

Although professionals are able to extract a considerable amount of wealth from amateurs, few stock pickers, if any, have the skill needed to beat the market consistently, year after year.

Odd as it may seem, I am my remembering self, and the experiencing self, who does my living, is like a stranger to me.

Knowing the importance of luck, you should be particularly suspicious when highly consistent patterns emerge from the comparison of successful and less successful firms. In the presence of randomness, regular patterns can only be mirages.

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.