Study of the Day: Almost Everyone Would Kill 1 Person to Save 5

By Hans Villarica

Nine out of 10 participants in a recent 3-D simulation of the classic "trolley problem" would sacrifice a person for the greater good

main shutterstock_27372304.jpg

PROBLEM: Would you kill one person so that five may live? As a thought experiment, most people would say yes and cite the greater good in their justification. But what if the sights, sounds, and stakes involved in that theoretical scenario became more real?

METHODOLOGY: Michigan State University researchers rebooted the classic trolley problem by giving it a virtual-reality twist. Instead of relying on pure imagination, the scientists used a head-mounted device to place the 147 participants in a 3-D setting where they could stop a malfunctioning boxcar threatening the lives of five people by flicking a switch that would reroute it toward a single person. (See the video below for a 2-D rendition of what the respondents saw.)

RESULTS: More than 90 percent of the participants diverted the boxcar. Only 14 allowed it to kill the five in its original path.

CONCLUSION: Most people would violate a moral rule for the welfare of the majority.

IMPLICATION: Our innate aversion to harming others can be overridden by rationality. As lead author Carlos David Navarrete puts it in a statement: "'Thou shalt not kill' can be overcome by considerations of the greater good."

SOURCE: The full study, "Virtual Morality: Emotion and Action in a Simulated Three-Dimensional Trolley Problem," is published in the journal Emotion.

Image: olly/Shutterstock. Video: Navarrete Research Lab.

This article available online at: