In the trolley problem some people think it is permissible for a bystander to turn the trolley onto the one to save the five. But many of those same people do not think it permissible to push a fat man onto the track to stop the trolley from running over the five.
The Trolley Problem is not to say whether this opinion is correct, but to explain what non-moral difference between these cases could reasonably lead people to these different verdicts in these two cases. This is a problem even for someone who does not think it permissible to turn from the one onto the five.
In what we may call the standard trolley case a bystander has the choice of throwing a switch which will divert the trolley or not throwing the switch. I take it that people who believe that it is permissible to throw the switch in the standard case believe the following.
It is permissible for you to do something, α, that kills one person if:
i) by doing α you prevent the death of five people.
ii) if you refrain from doing α the five people will die.
The Problem is why this principle does not also permit pushing the fat man in front of the trolley.
To see why consider the following cases.
Jones sees a runaway trolley coming down the track. He realizes that if it is not somehow stopped it will kill five people in its path and ....
- a fat man happens to be walking along the track when a gust of wind pushes him in front of the trolley. The trolley hits the fat man, killing him but stopping the trolley before it can hit the five.
- a fat man happens to be standing beside Jones. Jones points out the oncoming trolley to the fat man who otherwise would not have noticed it in time. Sizing up the situation, the fat man throws himself in front of the trolley. The trolley hits the fat man, killing him but stopping the trolley before it can hit the five.
- a fat man happens to be standing beside Jones. Jones points out to the fat man that if the fat man were to throw himself in front of the trolley this would likely prevent the trolley from killing the five, though it would almost certainly killl the fat man. The fat man would not have realized this unless Jones had pointed it out to him, but once he does, the fat man throws himself in front of the trolley.
- a fat man happens to be standing beside Jones. Jones realizes that the fat man’s bulk would stop the trolley and that the fat man does not see the trolley is coming. Jones tells the fat man that they are giving away free ice cream on the other side of track but supplies are running out. As Jones expected, the fat man runs across the track to get the ice cream. The Trolley hits the fat man, killing him but stopping the trolley before it can hit the five.
- a fat man and his son happen to be standing beside Jones. Jones grabs the fat man's son and puts a knife to his throat. Jones tells the fat man that unless he throws himself in front of the trolley, Jones will kill his son. The fat man throws himself in front of the trolley. The trolley hits the fat man, killing him but stopping the trolley before it can hit the five. Jones does not kill the fat man's son.
- a fat man and his two sons happen to be standing beside Jones. Jones grabs one of the fat man's sons and puts a knife to his throat. Jones tell the fat man that unless he throws himself in front of the trolley, Jones will kill his son. The fat man says he does not believe Jones will carry through on the threat. Jones cuts the son's throat, killing him. Jones then grabs the fat man's other son and repeats his threat. The fat man throws himself in front of the trolley. The trolley hits the fat man, killing him but stopping the trolley before it can hit the five. Jones does not kill the fat man's remaining son.
- a fat man happens to be standing beside Jones. Realizing the fat man's bulk would stop the trolley Jones pushes him onto the tracks. The trolley hits the fat man, killing him but stopping the trolley before it can hit the five.
My question is not about whether Jones behavior is permissible in any of these cases. My question is this: in cases 1 through 7, who prevents the death of the five?
It seems to me clear that in every case the answer is "the fat man".
In (1) the fat man saves the five involuntarily and unwittingly. In (2-3) the fat man saves the five voluntarily and wittingly. In (4) the fat man's voluntary action (crossing the track) prevents the death of the five, but the fat man prevents the deaths unwittingly. In (5) and (6) the fat man is coerced. Philosophers will disagree about whether coerced actions are truly voluntary, but never mind: What the fat man is coerced into doing is preventing the deaths of the five. In case (7) as in (1), the fat man prevents the death of the five involuntarily and unwittingly.
What about Jones? Well in (1) he does nothing to prevent any death. In cases (2-7) he is a cause of Jones preventing the death of the five. In case 3 he persuades the fat man to prevent the deaths. In cases 4, he tricks the fat man into preventing the deaths. In cases (4-5) he coerces the fat man into preventing the death. And in case (7) he forces the fat man to prevent the deaths. But in none of these cases does Jones prevent the deaths. If Jones were himself fat, we could, in each case, challenge him to explain why he didn't prevent the deaths himself instead of allowing or forcing the fat man to do so.
The difference then between the fat man cases and the standard case is that in fat man cases the agent does not satisfy (i).
