October 28, 2024
Kai Macann
The Trolley Problem
Would you kill one person to save five?
The Trolley Problem
You've probably heard of it before. The most famous thought experiment in philosophy, but if you haven't, it goes like this...
The brakes of a trolley have seized. It’s out of control. Given the trolley’s speed and direction it will inevitably run over five people working on the track, killing them instantly. As you watch the trolley barrelling towards the workers your hands reach out for the lever in front of you. If you pull the lever, instead of killing the five workers, the trolley will divert onto a second track where only one person is working.
Discussion Question: Should you pull the lever?
History
This dilemma is a common retelling of the thought experiment known as "the trolley problem". Originally thought of by Philippa Foot in 1967, the trolley problem is designed to ask what we should do when the interests of human beings conflict.
Consequentialist Approaches
Many people don’t see the dilemma here. Kill one instead of five, right? Isn’t it obvious? You want to choose actions that avoid the most pain and create the most pleasure by saving lives. This line of thinking is known as “consequentialism”, where actions are picked purely based on what will lead to the best consequences.
This line of thinking is a slippery slope, however. Philosopher Judith Jarvis Thomson poses a variant of Philippa Foot's Trolley Problem...
The brakes of a trolley have seized. It’s out of control. This time there are no workers at all, but instead five mafia members in workmen's clothing. The mafia left one of the workers tied up on the second track, assuming you would kill the one to save the five.
Discussion Question: Who do you kill?
In this variation, you are taking into consideration the accountability of each person on the track. If you kill the five mafia members because they are guilty, where does it end?
- Would you kill a regular person over a doctor because the doctor is more able to save other people?
- Would you kill an adult over a child because of their life span?
- Or a man over a woman because women live longer?
One website that tests out your bias through trolley problem variations such as Thomson's is The Moral Machine.
I think you get my point though... Where do you draw the line? Most people start feeling uncomfortable making these decisions. "Playing God".
More Variations
Things get more complicated however when you contrast it with some other variations of the thought experiment.
The brakes of a trolley have seized. It’s heading down the track ready to kill five workers. This time there is no second track, instead, you watch from a bridge directly above. In front of you is large man, and pushing his body onto the track is the only thing that will slow the trolley enough to save the five workers.
Discussion Question: Do you push the man?
In surveys when this question is asked, most people say that they would not push the large man. But what's the difference? In both situations you're killing one to save five. Is it different just because you feel more responsible for the death?
Philippa Foot poses a similar dilemma known as the transplant problem...
You are a doctor. You have five patients in dire need of various transplants; two need one lung each, two need a kidney each, and the fifth needs a heart. If they do not get these organs today, they will die. A young man with the right blood-type and in excellent health has just entered the clinic. You ask him if he is willing to be a donor, and he says that while he is sympathetic, he is unwilling to donate at the cost of his life.
Discussion Question: Should you harvest the man’s organs anyway?
While most people says that they would flip the switch, many don't think it is justified to harvest someone’s organs against their will, or push someone in front of a trolley. But why not? In each of these cases, it’s a matter of killing one to save five.
Some philosophers say that the difference is consent. This patient did not consent to the transplant, and so a doctor cannot operate. However, as Thomson points out:
One of the other variants Thomson provided was the Mayor Variant.
There's a runaway trolley, about to kill five workmen on the track. The righthand track is a dead end, unused in ten years. The mayor has set up picnic tables on it and invited convalescents at the nearby City Hospital to have their meals there. In the words of Thomson, "guaranteeing them that no trolleys will ever, for any reason, be turned onto the track." Only one convalescent has arrived yet, he is there because of you and your promise alone. Do you kill him, or let the five workers die?
Discussion Question: Who do you kill?
Does the fact that you made a promise make it acceptable to kill five instead of one? Wouldn’t sacrificing the one create the best consequence? Here enters “deontology”, the belief that some rules and principles are more important than consequences alone.
Deontology
Deontological theories tend to explain this dissonance between the trolley problem and the other thought experiments. Agent-centred deontology for example, suggests that you have more of an obligation to the people you are personally responsible for, such as the convalescent you made a promise to. Or if you were a parent and your kids were on one track, you'd have more of an obligation to protect them as their wellbeing is your responsibility while a stranger's is not.
Another theory, "the Doctrine of Doing and Allowing" states that it is worse to do harm than to allow it. This theory explains why you might be permitted to “let die” in the Trolley Problem but are not permitted to "kill" in The "Fat Man" Problem or The Transplant Problem.
Similarly, "The Doctrine of Double Effect" states that you are permitted to do an action with a negative consequence, if the good outweighs the bad and the good thing is not the same as the bad thing. For example, you are permitted to divert the track in the trolley problem because you’re saving five lives, the death of one is merely an unfortunate by-product. In the words of Philippa Foot:
This might also be why you are not permitted to push the large man, as his death is inherently part of your plan, not just a by-product. If he didn't get run over, then you would have failed.
These deontological theories are not without flaw however. Philippa Foot has pointed out that one could argue that it wasn't their intention for the man to die, they just wanted his body to slow down a 40-tonne vehicle travelling at 50km/h... "if he happened to die because of that, that's not on me."
Real-World Applications
It’s easy at this point to say that “trolleyology” is too abstract, with no real-world value. Many people also criticise the thought experiments for being too sterile—people would likely act differently in real life.
However, there are many situations in the real world where people sit down and make decisions based on what they cannot see in front of them. Whether it's a runaway trolley, a self-driving car, or even something that doesn't involve murdering people with runaway vehicles.
The point of thought experiments such as the trolley problem is to provide "edge cases" where our values and intuition are inconsistent and lead to unexpected results. Having these simple case studies help keep ourselves accountable for our ethical decisions.