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A Hands-on Approach to the Trolley Problem

New research finds our moral impulses may vary considerably depending on whether we're thinking about them, or acting on them.

The Good Place, surely the best moral-philosophy-grounded sitcom ever, recently dealt head-on with a seminal experiment in ethical decision-making: the Trolley Dilemma. This classic features several scenarios that pose the same tough question: whether you are willing to kill one person to save the lives of five others.

The non-human character played by Ted Danson, who is attempting to understand human behavior, finds he is dissatisfied with simply considering this issue in a classroom setting. So he snaps his fingers and, voila: He and his ethics teacher find themselves in a trolley that is speeding toward a group of workmen. Actively kill someone, or passively let five die? Suddenly the decision is real and immediate.

New research suggests that, whatever his motivation, Danson's decision to take the problem out of the realm of the theoretical was a good one. In two studies, people's responses to this sort of moral dilemma varied enormously, depending on whether their response required the exertion of physical force.

Perhaps surprisingly, it found people who experienced the actual sensation of pushing someone to his death were more likely to do just that—and thereby save the five others—than those who simply pondered the issue and made a decision.

"This research highlights our proneness to moral inconsistency," lead author Kathryn Francis, a philosopher and psychologist at the University of Reading, said in announcing the findings, which are published in the journal Scientific Reports. "What we say and what we do can be very different."

To discover just how different they are, the researchers used a sophisticated virtual-reality system. In their key experiment, they compared how three groups of participants reacted to a version of the problem in which they had the option to push one person in front of a speeding train. They understood that doing so would stop the train—and save the lives of five workmen on a nearby bridge.

One group of 20 participants was simply presented with the dilemma and asked to make a judgment. (They were given eight seconds to do so.) For another 20 participants, there was a physical component added: Those who chose to push the person to his death did so by applying pressure to a joystick.

The experience was still more realistic for the final group of 25; to stop the trolley, they had to apply pressure to a human figure. This "interactive sculpture mechanism" was "designed in the shape of a large person's back."

The results: Only 10 percent of those in the first group said it was morally acceptable to push one person to his death to save five others. But that figure increased to 63.3 percent in the joystick group, and 56 percent among those who encountered the human-like figure.

The researchers aren't sure what accounts for these large differences, but they note that, according to one school of thought, mental judgments are "influenced by cultural norms," whereas "action choices are driven by egocentric perspectives." This suggests those who are simply thinking about the problem may focus more on how they will be judged by others, making them more hesitant to act.

The results yielded one additional interesting finding: Participants with psychopathic tendencies tended to exert more force in pushing the guy onto the tracks, or taking similar actions. This implies that, under certain circumstances, there might be an upside to these otherwise destructive traits.

So the next time you are pondering a moral dilemma, be aware that how you respond in the moment may be quite different from how you respond in theory. But then, any demon could have told you that.