Belief Updating in Moral Dilemmas

Moral psychologists have shown that people's past moral experiences can affect their subsequent moral decisions. One prominent finding in this line of research is that when people make a judgment about the Trolley dilemma after considering the Footbridge dilemma, they are significantly less likely to decide it is acceptable to redirect a train to save five people. Additionally, this ordering effect is asymmetrical, as making a judgment about the Trolley dilemma has little to no effect on people's judgments about the Footbridge dilemma. We argue that this asymmetry is the result of a difference in how each dilemma affects people's beliefs about the importance of saving lives. In two experiments, we show that considering the Footbridge dilemma disconfirms these beliefs, while considering the Trolley dilemma does not significantly affect them. Consistent with predictions of sequential learning models, our findings offer a clear and parsimonious account of the asymmetry in the ordering effect.