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.

There are some conditions where you have to trust your intuition.

However, optimism is highly valued, socially and in the market; people and firms reward the providers of dangerously misleading information more than they reward truth tellers. One of the lessons of the financial crisis that led to the Great Recession is that there are periods in which competition, among experts and among organizations, creates powerful forces that favor a collective blindness to risk and uncertainty.

Human beings cannot comprehend very large or very small numbers. It would be useful for us to acknowledge that fact.

I don't try to be clever at all. The idea that I could see what no one else can is an illusion.

There is general agreement among researchers that nearly all stock pickers, whether they know it or not-and few of them do-are playing a game of chance.

The confidence people have in their beliefs is not a measure of the quality of evidence but of the coherence of the story the mind has managed to construct.