The Devil Is in the Deliberation: Thinking Too Much Reduces Preference Consistency

In five experiments we found that deliberation reduces preference consistency. In experiments 1 and 2, participants who deliberated on their preferences were less consistent in their evaluations compared to those who did not deliberate. Experiment 3 demonstrated that this effect is due to the impediment of deliberation and not to the benefit of nondeliberation. We hypothesized that deliberation leads to the inconsistent weighting of information, especially when the information is complex. As such, we predicted and found in experiments 4 and 5 that the extent to which deliberation decreases preference consistency depends upon the complexity of the information.