Pulling the Lever in a Subway Problem

A passenger on the MBTA Red Line pulled the emergency brake after a rider’s arm appeared caught in a closing door, stopping the train before it accelerated out of the station. The author, who was aboard and had shouted for someone to act, estimated the delay could have cost roughly 25,000 riders an hour, or about 4.3 years of waking life in aggregate, against a worst case of permanent arm injury. Other passengers closer to the door later said only the man’s bag was trapped, not his arm, and that he refused to let go of it as the train began moving. The episode, revisited at an effective altruism dinner, illustrates how real-world moral choices unfold under uncertainty rather than with the clear stakes of thought experiments like the trolley problem. The key question is how decision-makers can act robustly when they may have misread the situation, a theme the author ties to Scanlon’s Transmitter Room case.