Overconfidence is a powerful source of illusions, primarily determined by the quality and coherence of the story that you can construct, not by its validity.
Daniel KahnemanPeople'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.
Daniel KahnemanHowever, 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.
Daniel KahnemanTo 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.
Daniel Kahneman