So, there's a vehicle traveling down the train tracks, and there are 5 people that are tied up on the train tracks, but there is a fat man at the top of the bridge with you that you can push down to prevent the vehicle from killing all 5 of the tied up people at the bottom, do you push the fat man to save the 5 people, or do you let the vehicle run over the five people while sparing the fat man at the top of the bridge?
This is a thought experiment on ethics, on if sacrificing a person for a larger number of people is considered ethical by others.