Killing 1 Person to Save 5

Researchers test a famous ethical dilemma called the "trolley problem" in a very real setting. Christie Nicholson reports

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Would you kill one person to save five others?

Philosophers have posed this moral dilemma for decades. Typically they present the situation as a mental exercise. A runaway train is about to strike five people walking along the track. You can reroute the train and save the five people. But you will wind up killing one person walking on the other track.

Recently, researchers tried to make the dilemma feel much more real. They placed 147 subjects in a 3-D virtual environment where they are in front of a railroad switch controlling two tracks. They watch five people hike along a track bordered by a ravine. A single person hikes along the other track. Suddenly a train comes barreling toward the five people. The subject has the option to reroute the train using a joystick.


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Ninety percent of the study subjects switched tracks, killing the lone hiker to save five. These findings match past studies that were only abstract thought experiments. The study is in the journal Emotion.

It appears that even in very realistic, action oriented situations, people will go through with a Sophie’s Choice, motivated by accomplishing the apparently greater good.

—Christie NIcholson

[The above text is a transcript of this podcast.]

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