How people cope with uncertainty due to chance or deception

In making social judgments people process effects caused by humans differently from effects caused by non-human agencies. We assume that when they have to predict outcomes that are attributed to non-human causes, people acknowledge their ignorance and try to focus on what is most diagnostic. However, when events are attributed to human agency, they believe that nothing is arbitrary and that one can understand the decision situation well enough to eliminate error. If so, then people should behave differently when an uncertainty is attributed to chance (a non-human agency) or to deception (a human agency). We tested this prediction using the probability-matching paradigm and found reasonable support for our analysis in four experiments. Individuals who attributed uncertainty to deception were less likely to adopt the optimal rule-based strategy than those who attributed it to chance. Indeed, only when the former were prevented from thinking about and elaborating the outcomes (the high-interference condition in Experiment 3) was their performance comparable to the level of individuals in the chance condition.