The trolley problem: would you kill one person to save many others?

A decades-old thought experiment reveals our inconsistent moral intuitions. What would you do?

In the 2015 British thriller Eye in the Sky, a military team locates a terrorist cell preparing an attack expected to kill hundreds. They command a drone that can drop a bomb on the terrorists, preventing their attack. As the team readies the bomb, their cameras spy a little girl selling bread within the blast radius. Should they go through with their mission - killing the girl in order to prevent the deaths of many others?

This modern-day moral dilemma has its roots in a classic philosophical thought experiment known as the trolley problem. Introduced in 1967 by Philippa Foot, the trolley problem illuminates the landscape of moral intuitions - the peculiar and sometimes surprising patterns of how we divide right from wrong.