Recent work shows an important asymmetry in lay intuitions about moral dilemmas. Most people think it is permissible to divert a train so that it will kill one innocent person instead of five, but most people think that it is not permissible to push a stranger in front of a train to save five innocents. We argue that recent emotion-based explanations of this asymmetry have neglected the contribution that rules make to reasoning about moral dilemmas. In two experiments, we find (...) that participants show a parallel asymmetry about versions of the dilemmas that have minimized emotional force. In a third experiment, we find that people distinguish between whether an action violates a moral rule and whether it is, all things considered, wrong. We propose that judgments of whether an action is wrong, all things considered, implicates a complex set of psychological processes, including representations of rules, emotional responses, and assessments of costs and benefits. (shrink)

The psychological and neurobiological processes underlying moral judgement have been the focus of many recent empirical studies1–11. Of central interest is whether emotions play a causal role in moral judgement, and, in parallel, how emotion-related areas of the brain contribute to moral judgement. Here we show that six patients with focal bilateral damage to the ventromedial prefrontal cortex (VMPC), a brain region necessary for the normal generation of emotions and, in particular, social emotions12–14, produce an abnor- mally ‘utilitarian’ pattern of (...) judgements on moral dilemmas that pit compelling considerations of aggregate welfare against highly emotionally aversive behaviours (for example, having to sacrifice one person’s life to save a number of other lives)7,8. In contrast, the VMPC patients’ judgements were normal in other classes of moral dilemmas. These findings indicate that, for a selective set of moral dilemmas, the VMPC is critical for normal judgements of right and wrong. The findings support a necessary role for emotion in the generation of those judgements. (shrink)