Placed in a scenario where you are in control of a train that is set in course to run over and kill 5 people, with the only way of avoiding such a catastrophe being to change the course to the only other available track onto which 1 person will be killed, would you change the course and kill 1, or do nothing and kill 5?
To most this seems obvious, change the course, and kill one, basically saving net lives. However ponder the similarities of the following scenario.
Placed in a scenario where you are in control of 6 people, in a future in which organ transplants are nearly 100% efficient, 5 people are in need of 5 different organs or they will die shortly, and 1 living person has all of their healthy organs, would you harvest the organs of the 1 healthy person to save the lives of the 5 in need of organs?
in the train scenario i would divert the track to the siding. though it would kill the one person i think it's the right thing to do since it will save the other five on the train.
in the case of the organ transplants i wouldn't kill the one person to harvest his organs. the person is perfectly healthy and i'm not prepared to kill that person with my own hands to secure organs for the other five.
to me it's the difference between being insulated from the act of causing a person to die in the first scenario and actually having to murder the person in the second scenario.
is that an answer to the questions posed by each scenario? there's no doubt that it's a thought experiment meant to poke at our moral compasses and it can be boiled down to cold logic of survival like in the scenarios you mention. but in those scenarios you're talking about making tough decisions to ensure you're own survival or or that of a loved one a la Sophie's choice.
the scenarios in Ninja's questions are not that at all. you have to decide whether you'd kill the man by diverting the train to a siding and in so doing save the 5 people on board the train. and in the second scenario would you murder the organ donor so you could harvest their organs thereby saving the 5 patients in need of transplants.
I think this is a little bit more complex, because I'm trying to ascertain as to why one choice seems so obvious and the other so hazy, when at the core they are so similar. It isn't as simple as "what can one do out of desperation?" This question is more "what is the ethical choice given the scenario?"
Well put, I think you've analyzed the mechanism that is the cause of difficulty when deciding, very well. However this leads me to another, possibly more important question. What is the ethical choice? Selfishly what makes the transplant scenario seem wrong, is that I'm an immediate victim, and in no way do I feel deserving. However to think selflessly, if possible, executing the transplants would seem logical, and in effect ethical it would seem. So the dilemma I would say is torn between viewing oneself as a victim, and logic. When reviewing the question, I feel compelled to somehow sway logic into finding a way to describe it as unethical, however such attempts fail. So in conclusion I would say that executing the procedure would be the right choice to make, as difficult as it would be.
I'm not sure there is a "right" ethical decision to be made. In both scenarios, regardless of the decision, your action (or inaction) results in saving a life or lives.
Why are five lives better than one? Are ethics a matter of quantity? If the five people were convicts, then it certainly doesn't seem right to sacrifice an innocent person to save them - so why does sacrificing an innocent person, who might otherwise live a happy life if not for these 5 people, seem right if the five people are "good" citizens?
I'm not saying I wouldn't save 5 lives instead of 1, but the moment a doctor saves several patients at the expense of my life, or a loved one, I have to question the ethic behind his decision.
Common Dawkins analogy. For the inevitable death/train scenario, I prefer the utilitarian method.
In the other scenario, in choosing not to kill the one does not mean you are choosing to kill the other five, but simply refusing to kill, period. Rhetorically, you can say that you're technically choosing to kill in both situations, but in the practical sense, you have more control over the latter than the former and the assertion doesn't really have legs to stand on.
So really the only difference is that in the second scenario you don't feel qualified to make a decision regarding another life, where as in the first, it is your decision to make. Practically that is what makes the difference.