Trolley problem
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The trolley problem is a thought experiment in ethics, first introduced by Philippa Foot[1], but also extensively analysed by Judith Jarvis Thomson[2][3] and, more recently, by Peter Unger[4] and Frances Kamm[5]. Similar problems have traditionally been addressed by criminal lawyers and are sometimes regulated in penal codes, especially in civil legal systems. A classical example of these problems became known as "the plank of Carneades", designed by Carneades to attack Stoic moral theories as inconsistent. Outside of the domain of traditional philosophical discussion, the trolley problem has been a significant feature in the fields of cognitive science and, more recently, of neuroethics, which tends to approach philosophical questions from a neuroscientific approach. Such dilemmas are intended to test the limits and weakness of the major moral theories addressing the issues set forth by ethics and morality in general.
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[edit] Overview
The problem is this[1]:
- A trolley is running out of control down a track. In its path are 5 people who have been tied to the track. Fortunately, you can flip a switch, which will lead the trolley down a different track to safety. Unfortunately, there is a single person tied to that track. Should you flip the switch?
A utilitarian view asserts that it is permissible to flip the switch. According to simple Utilitarianism, flipping the switch would be not only permissible, but, morally speaking, the better option (the other option being no action at all).
While simple utilitarian calculus seeks to justify this course of action, some non-utilitarians may also accept the view. Opponents might assert that, since moral wrongs are already in place in the situation, flipping the switch constitutes a participation in the moral wrong, making one partially responsible for the death when otherwise the mad philosopher would be the sole culprit. Additionally, opponents may point to the incommensurability of human lives.
It might also be justifiable to consider that simply being present in this situation and being able to influence its outcome constitutes an obligation to participate. If this were the case, then deciding to do nothing would be considered an immoral act.
Some critics argue that the actual fact of producing an all inclusive moral theory, capable of addressing with clarity such staged or otherwise very real dilemmas, might not be attainable after all. These critics point to the fact that moral standards are relative in every society. This position in philosophy is known as moral relativism.
[edit] Related problems
The initial trolley problem becomes more interesting when it is compared to other moral dilemmas.
[edit] The fat man
One such is that offered by Judith Jarvis Thomson:
- 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?
Resistance to this course of action seems strong; most people who approved of sacrificing one to save five in the first case do not approve in the second sort of case. This has led to attempts to find a non-relevant moral distinction between the two cases.
One clear distinction is that in the first case, one does not intend harm towards anyone - harming the one is just a side-effect of switching the trolley away from the five. However, in the second case, harming the one is an integral part of the plan to save the five. This is an argument Shelly Kagan considers, and ultimately rejects, in The Limits of Morality. [6]
So, some claim that the difference between the two cases is that in the second, you intend someone's death to save the five, and this is wrong, whereas in the first, you have no such intention. This solution is essentially an application of the doctrine of double effect, which says that you may take action which has bad side-effects, but deliberately intending harm (even for good causes) is wrong.
On the other hand, Thomson argues that an essential difference between the original trolley problem and this version with the fat man, is that in the first case, you merely deflect the harm, whereas in the second case, you have to do something to the fat man to save the five. Thomson says that in the first case, nobody has any more right than anyone else not to be run over, but in the second case, the fat man has a right not to be pushed in front of the trolley.
Act utilitarians deny this. So do some non-utilitarians such as Peter Unger, who rejects that it can make a substantive moral difference whether you bring the harm to the one or whether you move the one into the path of the harm. Note, however, that rule utilitarians do not have to accept this, and can say that pushing the fat man over the bridge violates a rule to which adherence is necessary for bringing about the greatest happiness for the greatest number.
Another distinction is that the first case is similar to a pilot in an airplane that has lost power and is about to crash and currently heading towards a heavily populated area. Even if he knows for sure that innocent people will die if he redirects the plane to a less populated area - people who are "uninvolved", he will actively turn the plane without hesitation. Whereas the second case is more related to the situation of "would you torture someone's family to get him to reveal the location of a nuclear bomb in a city". It may well be considered noble to sacrifice your own life to protect others, but morally or legally allowing murder of an innocent person in order to save five people is insufficient justification and falls far short of the nuclear bomb scenario normally invoked to try to get people to accept evil in some circumstances". The fact that either an accident or crime is already in progress does not normally justify miscellaneous murder.
[edit] The track that loops back
The claim that it is wrong to use the death of one to save five runs into a problem with "loop" variants like this:
- As before, a trolley is hurtling down a track towards five people. As in the first case, you can divert it onto a separate track. On this track is a single person. However, beyond that person, this track loops back onto the main line towards the five, and if it weren't for the presence of that person, who will stop the trolley, flipping the switch would not save the five. Should you flip the switch?
The only difference between this case and the original trolley problem is that an extra piece of track has been added, which seems a trivial difference (especially since the trolley won't travel down it anyway). So intuition may suggest that the answer should be the same as the original trolley problem – one may flip the switch. However, in this case, the death of the one actually is part of the plan to save the five.
The loop variant may not be fatal to the "using a person as a means" argument. This has been suggested by M. Costa in his 1987 article "Another Trip on the Trolley", where he points out that if we fail to act in this scenario we will effectively be allowing the five to become a means to save the one. If we do nothing then the impact of the trolley into the five will slow it down and prevent it from circling around and killing the one. As in either case some will become a means to saving others, then we are permitted to count the numbers. This approach requires that we downplay the moral difference between doing and allowing.
However, this line of reasoning is no longer applicable if a slight change is made to the track arrangements such that the one person was never in danger to begin with, even if the 5 people were absent. Or even with no track changes, if the one person is high on the gradient while the five are low, such that the trolley cannot reach the one. So the question has not been answered.
One way of justifying flipping the switch in this scenario is that this is actually a crime. The fat man tied to the track is there because of a criminal act. Thus it is similar to a hostage situation. The SWAT may choose to shoot through an innocent person in order to kill the hostage-taker, sparing the other hostages. Responsibility for the death in either case lies with the criminal, not the person who chose the least worst option to fight the crime. The parallel here is closer to a scenario where there is no loop, or even a person on the alternate track, but instead a hostage-taker says "don't flip the switch or I will kill the hostage". The person flipping the switch is not morally bound to give in to criminal blackmail.
Even in the situation where the people aren't tied down due to a criminal act, but simply happen to be there without the ability to warn them, the out-of-control trolley is similar to the out-of-control airplane. Either 5/500 or 1/100 people are going to die as a result of the accident already in progress, and it is normal to minimize the loss of life, despite the fact that the 1/100 are effectively being "used" to spare the life of the 5/500. The 100 people (and their property) in the less-densely-populated area do in fact stop the plane too. Responsibility for this goes back to any criminal negligence that caused the accident to occur in the first place.
[edit] Transplant
Here is an alternate case, due to Thompson, containing similar numbers and results, but without a trolley:
- 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.
As rare as it is to find someone who does not think we should turn the trolley, it is even rarer to find someone who thinks it is permissible for the doctor to murder this patient and harvest his organs.
One may attribute this to the specific role that doctors play in our society. They have sworn the hippocratic oath to "never do harm," not to "maximize good."
[edit] The man in the yard
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Unger argues extensively against traditional non-utilitarian responses to trolley problems. This is one of his examples:
- As before, a trolley is hurtling down a track towards five people. You can divert its path by colliding another trolley into it, but if you do, both will be derailed and go down a hill, and into a yard where a man is sleeping in a hammock. He would be killed. Should you proceed?
Responses to this are partly dependent on whether the reader has already encountered the standard trolley problem (since there is a desire to keep one's responses consistent), but Unger notes that people who have not encountered such problems before are quite likely to say that, in this case, the proposed action would be wrong.
Unger therefore argues that different responses to these sorts of problems are based more on psychology than ethics – in this new case, he says, the only important difference is that the man in the yard does not seem particularly "involved". Unger claims that people therefore believe the man is not "fair game", but says that this involvedness cannot make a moral difference.
Unger also considers cases which are more complex than the original trolley problem, involving more than just two results. In one such case, it is possible to (e) do nothing and let five die, or to do something which will (a) save the five and kill four (passengers of one or more trolleys and/or the hammock-sleeper), (b) save the five and kill three, (c) save the five and kill two, or (d) save the five and kill one. Most naïve subjects presented with this sort of case, claims Unger, will choose (d), to save the five by killing one, even if this course of action involves doing something very similar to killing the fat man, as in Thomson's case above.
This scenario is similar to the fact that whenever a crime is in progress and someone calls the police, even though it is known well in advance that calls to police each year end up creating pedestrian and motorist deaths due to accidents, very few people would consider disbanding the police to ensure that no innocents should die en-route to a crime scene. And in the case where the five aren't tied down due to a criminal act, it still falls into the category of diverting a crashing plane into a less-densely-populated area.
[edit] In cognitive science
The trolley problem was first imported into cognitive science from philosophy in a systematic way by John Mikhail[7], who began testing trolley problems on different groups of people, including children and people from non-Western cultures, in 1996, when he was a visiting graduate student in MIT’s Department of Brain and Cognitive Sciences. Mikhail hypothesized that factors such as gender, age, education level, and cultural background would have little influence on the judgments people make, in part because those judgments are generated by an unconscious “moral grammar” that is analogous in some respects to the unconscious linguistic grammars that support ordinary language use.[8] Preliminary results pointed in that direction, and Mikhail’s initial findings have been confirmed and expanded to more than 200,000 individuals from over 100 countries.[9]
[edit] In neuroethics
In taking a neuroscientific approach to the trolley problem, Joshua Greene[10] under Jonathan Cohen decided to examine the nature of brain response to moral and ethical conundra through the use of fMRI. In their more well-known experiments[11], Greene and Cohen analyzed subjects' responses to the morality of responses in both the trolley problem involving a switch, and a footbridge scenario analogous to the fat man variation of the trolley problem. Their hypothesis suggested that encountering such conflicts evokes both a strong emotional response as well as a reasoned cognitive response that tend to oppose one another. From the fMRI results, they have found that situations highly evoking a more prominent emotional response such as the fat man variant would result in significantly higher brain activity in brain regions associated with response conflict. Meanwhile, more conflict-neutral scenarios, such as the relatively disaffected switch variant, would produce more activity in brain regions associated with higher cognitive functions. The potential ethical ideas being broached, then, revolve around the human capacity for rational justification of moral decision making.
[edit] See also
[edit] References
This article includes a list of references or external links, but its sources remain unclear because it lacks inline citations. Please improve this article by introducing more precise citations where appropriate. (February 2008) |
- ^ a b Philippa Foot, The Problem of Abortion and the Doctrine of the Double Effect in Virtues and Vices (Oxford: Basil Blackwell, 1978)
- ^ Judith Jarvis Thomson, Killing, Letting Die, and the Trolley Problem, 59 The Monist 204-17 (1976)
- ^ Judith Jarvis Thomson, The Trolley Problem, 94 Yale Law Journal 1395-1415 (1985)
- ^ Peter Unger, Living High and Letting Die (Oxford: Oxford University Press, 1996)
- ^ Francis Myrna Kamm, Harming Some to Save Others, 57 Philosophical Studies 227-60 (1989)
- ^ Shelly Kagan, The Limits of Morality (Oxford: Oxford University Press, 1989)
- ^ Homepage of John Mikhail
- ^ John Mikhail, Universal Moral Grammar: Theory, Evidence, and the Future, Trends in Cognitive Sciences, 11, 143-152 (2007)
- ^ Greg Miller, The Roots of Morality, Science, 320, 734-737 (2008)
- ^ Homepage of Joshua Greene
- ^ Joshua D. Greene, "The secret joke of Kant’s soul", in Moral Psychology, Vol. 3: The Neuroscience of Morality, W. Sinnott-Armstrong, Ed., (Cambridge, MA: MIT Press)