Mental simulation of causality.

Abstract

We propose that people imagine alternatives to reality (counterfactuals) in assessing the causal role of a prior event. This process of mental simulation (Kahneman & Tversky, 1982) is used to derive novel predictions about the effects of default events on causal attribution. A default event is the alternative event that most readily comes to mind when a factual event is mentally mutated. The factual event is judged to be causal to the extent that its default undoes the outcome. In Experiment 1, a woman was described as having died from an allergic reaction to a meal ordered by her boss. When the boss was described as having considered another meal without the allergic ingredient, people were more likely to mutate his decision and his causal role in the death was judged to be greater than when the alternative meal was also said to have the allergic ingredient. In Experiment 2, a paraplegic couple was described as having died in an auto accident after having been denied a cab ride. People perceived the cabby's refusal to take the couple as a stronger cause of the deaths when his taking the couple would have undone the accident than when it would have not have. We conclude that an adequate theory of causal judgment requires an understanding of these counterfactual simulations.