If you’ve ever taken Philosophy 101 at university or had the misfortune of sitting next to a self-proclaimed philosopher at a party, you’ve probably heard of the Trolley Problem:
There is a runaway trolley barreling down the railway tracks. Ahead, on the tracks, there are five people tied up and unable to move. The trolley is headed straight for them. You are standing some distance off in the train yard, next to a lever. If you pull this lever, the trolley will switch to a different set of tracks. However, you notice that there is one person on the sidetrack. You have two (and only two) options:
- Do nothing, in which case the trolley will kill the five people on the main track.
- Pull the lever, diverting the trolley onto the sidetrack where it will kill one person.
Which is the more ethical option? Or, more simply: What is the right thing to do?
It’s a classic of ethics, and an untold number of hours have been spent trying to sort out the moral implications of this hypothetical situation. Many of you have probably seen this TED talk on the subject, which was one the truly great videos that rocketed TED into the mainstream – before it got bogged down in this TED X nonsense where hand drying techniques are apparently worth our attention. There’s even a whole book devoted to the subject (the Trolley Problem, not hand drying).
I’m not a huge fan of the Trolley Problem. It’s such a trite, simplified, and unrealistic conception of morality, where people line up on train tracks for some reason and every decision has obvious, expected consequences. If morality is about guiding our actions, what is the point of exploring a situation that has never occurred? We don’t lack moral conundrums that feature real people and real consequences, so why bother with this fabricated nonsense when there’s a whole world of moral decision-making happening around us just waiting for our attention? Worse, the Trolley Problem is annoying. It’s like the Matrix movies: a ham-fisted, frivolous, and downright goofy illustration of otherwise interesting philosophical ideas. I wouldn’t talk about the Trolley Problem unless I had to.
And, alas, I have to. Since it is a classic of moral philosophy, I have no choice but to discuss it, at least for a short time. As well, – I’m writing this through gritted teeth – there are some important insights that flow from the Trolley Problem that contribute to our understanding of the relationship between values and public policy. And I don’t say that lightly. So, strap in, put on those god-awful clothes you wore to your Philosophy 101 class, and let’s transport ourselves back in time. To keep things fun, I’ll break up the moral philosophy with some of my favourite images from the Trolley Problems forum throughout, which mostly poke fun at how overdone this moral paradox is:
Riffing on the Trolley Problem
The key insight of the Trolley Problem derives not from the problem itself, but from its variations and how they elicit different moral reactions based on relatively minor changes. For example, here’s the Fat Man Problem:
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 putting something very heavy 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?
In the body count, the Trolley Problem and the Fat Man Problem are identical. Pulling the lever and pushing the fat man lead to the same outcome: five people are spared and one person dies. However, people don’t react to the fat man problem in the same way. In the original Trolley Problem, surveys suggest that 90% of people would pull the lever (killing one person and saving five). This ratio is completely inversed when the Fat Man Problem is presented; 90% of people would prefer to see five people die than push the man to his death.
Things get more complicated when more variations are used. Here’s the Transplant Problem:
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.
Again, the body count is the same, but this example is clearly even more heinous than the Fat Man Problem. Pushing a man off a ledge is one thing, but violating the Hippocratic Oath, cutting open another human, and harvesting their organs is quite another.
Lessons from the Trolley Problem and Its Variations
The differing moral reactions from the Trolley Problem, the Fat Man Problem, and the Transplant Problem appear irrational, something that philosophers, who are trained to apply reason, seem unwilling to accept. They have dedicated a lot of time and grant money splitting hairs to determine the rational difference between these two situations. I’m not going to do that. However, I will provide three important insights that these problems illuminate (and explain why they are important for public policy).
Insight 1: Morals are not rational
Ethicists have folded themselves into pretzels in order to rationalize our moral reactions to these problems. A few common differences come up. One is the concept of consent. In the Trolley Problem, the consent of the single person would be impossible to get, while the doctor certainly could have asked if the healthy person wanted to sacrifice their lives for the good of the others. In cases where consent is possible, but not received, the act is more wrong (according to these ethicists, not me).
Another possible area of difference is the risk the victim takes. In the Trolley Problem, the one person is on the tracks, where any rational person could expect to get hit. In the Fat Man problem, it is a bystander, who has not taken any risk at all (expect by standing beside a potential murderer). In the Surgeon Problem, the potential victim has not run any risks. In fact, they were actually seeking treatment. In this view, perhaps it is the risk taken by the potential victims that makes the difference in our moral judgement.
There are others, but I won’t waste your time; these “explanations” are pointless. People’s reactions to the Trolley Problem (and its various iterations) are instant, emotional, and inexplicable. These are the hallmarks of the System 1 process of thinking, which contrasts with our System 2 thinking (i.e. slow, methodical, and rational).
As a result, it is missing the point to try to find a rule that justifies our every reaction. Morality is not rational. There is no moral law that can be applied to every situation to arrive at the proper outcome. Rather, individual moral preferences just exist. And it’s a waste of time to attempt to work backwards from the reaction to a consistent moral code that applies to every situation. The Trolley Problem and its iterations are an excellent illustration of this fact. Try as you might, you won’t land upon a convincing reason why pulling the lever is justified but stealing a traveller’s organs are not.
For policy makers, this is an extremely important point. Throw out your Bentham and your Kant. They may have a lot to say about morality in a theoretical sense, but they provide very little insight into how people actually think and act. If you’re interested in ensuring your policies are morally acceptable to your electorate, there’s only one way to do it: values analysis, which is built on the exploration of real moral reactions without judgement.
Insight 2: Moral reactions are broadly predictable (but not uniform).
Although moral reactions can’t be explained rationally, they can be predicted. We’re all human, and so we draw upon similar intuitions that serve as the basis of our moral compasses. Strong evidence of this comes from a 2020 paper that recorded reactions to the Trolley Problem and the Fat Man Problem from 70,000 participants in 40 countries. In every single country, pulling the lever to redirect a train was more acceptable than pushing the Fat Man to stop the train with his bulk.
However, this study showed that social convention can help shape moral views. In most Western countries, about 80% of people determined that it was correct to pull the lever under the Trolley Problem, but only about 55% believed that pushing the fat man was morally justified. However, Asian countries showed a far wider range of reactions. The statistics in Vietnam closely resembled those in Western countries, although Vietnamese participants showed a higher willingness to throw the Fat Man in front of the train (about 65% said they would). In contrast, Chinese participants were far more hesitant to act in both situations; 60% of them would have pulled the lever in the Trolley problem, and only about 30% would have pushed the fat man. Clearly, cultural norms and values play a role in shaping our moral reactions, and more research needs to be done to quantify these differences.
But demonstrating variance does not mean that moral reactions are unpredictable. With this evidence, I would hypothesise that all participants would be more disgusted by the Surgeon Problem than the Fat Man Problem. I may also predict that Chinese participants would be more repulsed than Western audiences overall. This doesn’t mean that I could predict exactly how an individual would react to any of the problems. That’s not possible. Rather, I could predict how large numbers of people would react, making use of social media, survey data, and comparative analysis as evidence.
Again, this is an important point for policy makers to consider. In the policy development stage, it is possible to take a systematic approach to predict moral reactions (and adapt the policy to reduce the violation of people’s values). If you can predict it, you can adapt to it.
Insight 3: Small changes can elicit very different moral reactions.
This is perhaps the most important insight of the Trolley Problem and its iterations. If Spock analysed these problems, he would probably conclude they are perfectly equivalent. On one hand, you can act and kill one person. On the other hand, five people die. That’s all there is to it.
But we’re not Spock, so seemingly insignificant alterations to the situation can create strongly different moral reactions. Our brain often processes inputs in unexpected (but predictable) ways, so minor points become prominent. Issues that appear similar at first glance are often very different in reality.
In developing policy, it’s critical to keep this in mind. One iteration of a government policy (such as a vaccination incentive program) could elicit a huge, negative moral reaction. A different way of setting up the same program may achieve the same ends for similar costs while avoiding backlash (it might even enjoy moral support). However, policy practitioners are unlikely to stumble upon the correct program design unless they do the work and analyse the issue through the lens of values.
Conclusion
And that’s a wrap. I’ll never bring up these types of hypotheticals ever again. If you want to discuss the technical and philosophical underpinnings of the Trolley Problem, I direct you to the nearest philosophy department. To close off, here’s a brilliant solution by some kid on the internet: