You’re on a footbridge above some tram tracks; a tram approaches out of control; five people have been tied to the track by a mad philosopher; the tram can only be stopped by a heavy weight; you could push a fat man standing next to you onto the track into the path of the tram, killing him but saving the five on the track.
This time, there’s a crucial difference. You know with absolute certainty that the fat man standing next to you on the bridge is the mad philosopher. He is responsible not only for tying the five people to the track but also for sabotaging the tram’s brakes. Incensed by a philosophical argument and rising tram prices, he deliberately set out to cause an accident.
As before, the only way to stop the tram and save the lives of the five people tied to the track is to push the fat philosopher off the footbridge into the path of the tram.
Do you push him onto the track or allow the tram to continue?