Scenario 1: A trolley is hurrying down the track towards 5 men obliviously working on the rails. You cannot warn the men in time, but, by your side, is a switch that will divert the ill-fated trolley onto another track. BUT, on that track is a single man working on the rails. Flip the switch and the one man dies. If you don't, 5 men will die.
Question 1: Do you flip the switch?
Scenario 2: Same trolley as above but no switch, no second track. You are on a bridge above the track. There is a huge man watching in horror with you and it’s clear to your mind and truthful: if you push him off the bridge into the path of the trolley it will stop it in time to save the 5 men. (No you’re not big enough, yes the physics seem odd, and there’s no arguing with the hypothetical :-))
Question 2: Do you push the man?
Answered both yet?
Are you a normal human :-)?
It seems, in surveys, most all people choose to throw the switch (kill 1 man and save 5), but they will not push 1 man to his death and save 5. Why? Why does it seem right to so many to kill a man by moving one mass buy not by moving another? Five lives are saved in both actions, and you 100% know you’re murdering one man in both.
An interesting radio program on this question and possible reasons for why we take different paths on such moral quandaries is found streaming in mp3 here (the whole program), or here (just the trolley bit). From this radiolab program (I'd recommend the whole program).
Eh, it seemed relevant to some of these topics, but interesting nonetheless.