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.

Groups tend to be more extreme than individuals.

I have always believed that scientific research is another domain where a form of optimism is essential to success: I have yet to meet a successful scientist who lacks the ability to exaggerate the importance of what he or she is doing, and I believe that someone who lacks a delusional sense of significance will wilt in the face of repeated experiences of multiple small failures and rare successes, the fate of most researchers.

We have associations to things. We have, you know, we have associations to tables and to - and to dogs and to cats and to Harvard professors, and that's the way the mind works. It's an association machine.

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

Nobody would say, 'I'm voting for this guy because he's got the stronger chin,' but that, in fact, is partly what happens.

Experienced happiness refers to your feelings, to how happy you are as you live your life. In contrast, the satisfaction of the remembering self refers to your feelings when you think about your life.