An uncontrolled train is heading towards 5 people on the tracks. These people will be killed if the train continues to run. You are standing next to a tall man on a catwalk over the rails. The only way to save the five is to push the man over the catwalk so that he stops the bandwagon, but if you do that the big man will be killed. Is it morally permissible to push the man over the catwalk in order to save the other five people?