IS IT more morally acceptable to kill someone accidentally, or intend to kill them but fail? Most people would go for the first option ā unless their brains are impaired in regions key to feeling emotion or divining the intentions of others.
This discovery is helping to unravel how we make moral judgements and has implications for peopleās fitness to serve as jurors or judges.
To probe emotionās role in moral decision-making, and her colleagues at the Massachusetts Institute of Technology turned to nine people whose emotional responses were impaired due to damage in the ventromedial prefrontal cortex.
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Young presented these people with 24 moral dilemmas, each consisting of four different scenarios of varying acceptability. In one, for example, someone kills another by mistakenly adding poison to their coffee instead of sugar. In another scenario, a person tries but fails to kill another by deliberately poisoning their coffee. Participants ranked the moral acceptability of each scenario on a scale of 1 to 7.
The volunteers with brain damage gave failed attempts at intentional harm a 5, rating it twice as permissible as the other volunteers, who opted for 2.5. And the impaired group all rated accidental harm to someone as being less morally acceptable than failed attempts at deliberate harm (Neuron, ).
āThey would judge attempted harm, including murder, as permissible as long as no actual harm was done,ā says Young. Perhaps without intact emotional responses, a failed attempt to kill just doesnāt seem upsetting. āNormally, intention always trumps outcome,ā she adds.
āThey judged attempted harm, including murder, as permissible as long as no actual harm was doneā
But emotion isnāt all thatās required to make moral judgements. You must also be able to divine the intentions of others. So Youngās team temporarily disabled a brain region considered indispensable for this ā the right temporoparietal junction ā in 20 volunteers using transcranial magnetic stimulation. This time, volunteers rated failed attempts at harming others as 15 per cent more acceptable than when their brains were not undergoing TMS (Proceedings of the National Academy of Sciences, ). Young concludes that both emotion and recognising intent in others are key to moral judgements.
of Vanderbilt University in Nashville, Tennessee, highlights the findingsā relevance to the law. āThey reveal regions that simply must be intact and functioning for people to make important moral and legal decisions,ā he says.
