Moral principles or consumer preferences? Alternative framings of the trolley problem.

We created paired moral dilemmas with minimal contrasts in wording, a research strategy that has been advocated as a way to empirically establish principles operative in a domain-specific moral psychology. However, the candidate "principles" we tested were not derived from work in moral philosophy, but rather from work in the areas of consumer choice and risk perception. Participants were paradoxically less likely to choose an action that sacrifices one life to save others when they were asked to provide more reasons for doing so (Experiment 1), and their willingness to sacrifice lives depended not only on how many lives would be saved, but on the number of lives at risk (Experiment 2). The latter effect was also found in a within-subjects design (Experiment 3). These findings suggest caution in the use of artificial dilemmas as a key testbed for revealing principled bases for moral judgment.