We tend not to discuss ethical dilemmas in the abstract, if for no other reason that they usually tend to be real posers.Take this famous dilemma: There is a runaway trolley headed in your direction, and in its path there are five people tied to the track. You find you are standing right next to a switch which could shunt the trolley off on a siding. You proceed to pull the switch, only to find there is a single person tied to the track on the siding.
The Utilitarians would say that it is a better thing to sacrifice one life rather than five—all other things being equal. But are they really equal? What if the five people tied to the track are all serial child molesters, and the single person tied to the siding is Pope Francis? Also, are there any people on the trolley? If so, wouldn’t they all risk dying in any case?
There is a variant of this dilemma, but without a switch and a siding. Again, we have a runaway trolley, again with five people tied to the track. You are standing on a footbridge over the track with a fat man whom you don’t know. You are between the runaway trolley and the five persons on the track. Should you push the fat man off the footbridge so that he lands in the path of the trolley, leading to a derailment upon impact?
In the first case, most people would throw the switch in the first case, but few would push the fat man to his death in the path of the trolley.
My own preference is to avoid situations where I am anywhere near any runaway trolleys, especially since I could be considered a fat man myself.