Trolley problem

The trolley problem is a thought experiment in moral philosophy and moral psychology with many variations, involving hypothetical ethical dilemmas about whether to sacrifice one person to save a larger number of people. The series usually begins with a scenario in which a runaway trolley (tram) or train is on course to collide with and kill a number of people (traditionally five) tied to the tracks, but a driver or bystander can intervene and divert the vehicle to kill just one person on a different track. Then other variations of the runaway vehicle, and analogous life-and-death dilemmas (medical, judicial, etc.) are posed, each containing the option either to do nothing—in which case several people will be killed—or to intervene and sacrifice one initially "safe" person to save the others. Opinions on the ethics of each scenario turn out to be sensitive to details of the story that may seem immaterial to the abstract dilemma. The question of formulating a general principle that can account for the differing judgments arising in different variants of the story was raised in 1967 as part of an analysis of debates on abortion and the doctrine of double effect by the English philosopher Philippa Foot. Later dubbed "the trolley problem" by Judith Jarvis Thomson in a 1976 article that catalyzed a large literature, the subject refers to the meta-problem of why different judgements are arrived at in particular instances. Thomson and the philosophers Frances Kamm and Peter Unger have analyzed the trolley problem extensively. Thomson's 1976 article initiated the literature on the trolley problem as a subject in its own right. Characteristic of this literature are colourful and increasingly absurd alternative scenarios in which the sacrificed person is instead pushed onto the tracks as a way to stop the trolley, has his organs harvested to...