For the full explanation, see Ethical Dilemmas and Human Morality, part 1, written almost exactly a year ago.
We had a particular debate recently on consistency in moral dilemmas. In particular, we went over two variants of the Trolley Problem: the fat man and the transplant. One side argued that you must pick the same answer in both variants, while the other side argued that it was rational to have opposite answers in the two cases. I argued for the latter.
Here is Wikipedia’s preferred formulations of the two variants:
As before, a trolley is hurtling down a track towards five people. You are on a bridge under which it will pass, and you can stop it by dropping a heavy weight in front of it. As it happens, there is a very fat man next to you – your only way to stop the trolley is to push him over the bridge and onto the track, killing him to save five. Should you proceed?
A brilliant transplant surgeon has five patients, each in need of a different organ, each of whom will die without that organ. Unfortunately, there are no organs available to perform any of these five transplant operations. A healthy young traveler, just passing through the city the doctor works in, comes in for a routine checkup. In the course of doing the checkup, the doctor discovers that his organs are compatible with all five of his dying patients. Suppose further that if the young man were to disappear, no one would suspect the doctor.
In the original trolley problem, most people would sacrifice one person to save five. However, in the fat man variation, not as many people are willing to take the action. And in transplant, very few people agree that harvesting the healthy traveler’s organs is the correct move.
This is quite inconsistent. Why would you be willing to sacrifice one person to save five in some cases, but not in others? Shouldn’t the results be the same?
I argued that it is morally feasible to have different answers to this question, especially in regards to saying yes to the original or fat man case, and saying no in the transplant case.
From a utilitarian perspective, these scenarios are not the same, namely because people contribute different values to society. In the standard trolley example, there is no reason to suspect that the one person laid on one of the tracks is different from any of the five people laid on the other track. Since we are given no other information as to who these people are (of course, the situation changes if we have more information), the best bet is to save the five. Similar is the fat man scenario.
In the transplant case, however, we are given additional information: given that someone is about to die due to the failure of some vital organ, they are probably contributing less to society than the healthy traveler undergoing a routine checkup. Now, this effect may not be strong enough to warrant the sacrifice of 5 people, but it clearly makes the transplant scenario different from the trolley or the fat man.
Now, if the transplant case were replaced with sacrificing one life to save a million, then the problem is entirely changed as well. Similarly, in the trolley problem, if we said the five people were all serial killers and the one person on the other track was a normal hard-working person, that changes the situation.
Since we can change around the answers so easily, there doesn’t seem to be a fundamental one life versus five lives struggle at hand, but rather, a combination of other factors. We can answer the question based on what information we have about the people involved, and since these situations imply different types of people, we are not morally obliged to answer the same for all variants of the problem.