Shelley E. Taylor and Peter M. Gollwitzer
JOURNAL OF PERSONALITY AND SOCIAL PSYCHOLOGY, 1995
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S. E. Taylor and J. D. Brown's (1988) position that mentally healthy people exhibit positive illusions raises a dilemma: How do people function effectively if their perceptions are positively biased? Using Gollwitzer's deliberative-implemental mindset distinction, we assessed whether people in a deliberative mindset show less evidence of positive illusions than people in an implemental mindset. Participants completed a mindset task and assessments of mood, self-perceptions, and perceived (invulnerability to risk. Deliberation led to worsened mood, greater perceived risk, and poorer self-perceptions, relative to implementation; control (no mindset) participants typically scored in between. Study 3 demonstrated that the mindset manipulation corresponds to how people actually make decisions or implement them. Results suggest that people use relatively realistic thinking when setting goals and more positive thinking when implementing them.

This paper makes a big step toward answering how Positive Illusions are tolerable. Why doesn't all this delusion result in failure? It seems that when we debate a difficult problem the bias largely disappears. Interestingly, it also seems that positive bias is generally enhanced when we are pursuing a goal already decided on. This is consistent with the general idea that positive bias can be regarded as an accommodation the intractability of predicting success. In other words, it is an aid to risk-taking.