A runaway trolley rushes toward five people standing on the tracks, and it will surely kill them all. Fortunately, you can reach a switch that will turn the trolley onto a side track – but then you notice that one other person is standing there. Is it morally permissible for you to turn the trolley to that side track, where it will kill one person instead of five? Is it not only morally permissible, but even morally required? This classic thought experiment is a mainstay in the repertoire of law school hypotheticals, often raised alongside cases about cannibalism at sea, tossing people from overcrowded lifeboats, or destroying buildings to save a city from fire.
Bert I. Huang,
Law and Moral Dilemmas,
Harv. L. Rev.
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