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.

We are often confident even when we are wrong, and an objective observer is more likely to detect our errors than we are.

People's mood is really determined primarily by their genetic make-up and personality, and in the second place by their immediate context, and only in the third and fourth place by worries and concerns and other things like that.

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

An executive might have a very strong intuition that a given product has promise, without considering the probability that a rival is already ahead in developing the same product.

The evidence is unequivocal, there's a great deal more luck than skill in people getting very rich.

Employers who violate rules of fairness are punished by reduced productivity, and merchants who follow unfair pricing policies can expect to lose sales.