Would you kill the fat man?

Most people agree that it is a good idea to be… well, good. In a lot of ways, the question of why is pretty simple; after all, it’s pretty nice being able to take a walk without worrying that people are constantly trying to murder you!

But how should we be good? Even if we do good simply because it is better for everyone, what is the best way we can be good? And how do we decide? It is questions like these that make up the study of ethics, or moral philosophy.

When people study ethics, they pose what are known as ‘thought experiments’. A thought experiment is a little bit like a scientific experiment: it’s an attempt to test for something very specific, in a controlled environment. So, just like you might test the flammability of magnesium in a lab, away from other things that might be flammable, so too do you test certain ethical principles inside your head, away from the messiness of the real world.

Furthermore, after we have the results of our experiment, we can then apply those results to the real world, safe in the knowledge that the knowledge that we have has not been compromised.

Now, a very famous set of philosophical thought experiments are called the “trolley problems” – so called because they involve a trolley (an old-fashioned name for a tram):

The problem goes as follows:

Imagine that you are having a lovely day out and about, and you are walking along some tram tracks. As you walk along the tracks you see, up in the distance, that the tracks split in two.

However, that is not all: as you draw closer to the split, you are astounded to see six people tied up, struggling to escape. Clearly, some villain has trapped these poor souls! Furthermore, out of the six, you see that five are tied up on the right fork of the track, and one is tied up on the left fork.

Just as you see the six people, you feel the tracks beside you begin to rumble, and you turn to see a tram hurtling towards the fork in the track. Unless you do something, the tram will kill the five people on the right fork of the track.

Two things are immediately clear: first, that the tram is going too fast to stop; and second, that the people are too far away for you to untie any of them. However, as you begin to panic, you realise a third thing: that there is a railway switch beside you. If you pull it, you can redirect the course of the tram and kill only the one person on the left fork, instead of the five on the right.

What do you do?

Now, most people, when asked, choose to pull the lever, making sure that only one person dies. After all, even if one person dies, you still have a net gain of four lives, whereas if you call all five on the right track, you have a net loss of four lives. It seems reasonable to save as many people as possible!

In philosophy, this view is called ’utilitarianism’ (yoo-TILL-i-TAR-i-AN-ism) – that is, the best way how to do good is to do the best for the largest number of people. Famous Australian philosopher, Peter Singer, is a modern philosopher who holds utilitarian views.

Conversely, if you decided to not pull the lever because, say, you think it is more wrong to kill one person than to let five people die, then that is called deontology (DEY-on-TOLL-o-DJEE). American philosopher Thomas Nagel is a modern philosopher who holds deontological views.

“Okay,” you might be thinking. “That was easy. Now what?”

All right, wise guy. How’s this for a curve ball?

Imagine that, instead of standing by the track with a lever, you are instead standing on a footbridge over the track. Also imagine that, instead of there being a fork, the tram is on a straight stretch of track, at the end of which are five people who are tied up and can’t escape.

Once again, the tram is going so fast that it doesn’t have time to slow down, and nor do you have time to untie anyone. Instead, you are sharing the footbridge with an extremely large, fat man, who is standing on the edge, oblivious to what is below.

You realise then that the man is so large and so fat that, if you pushed him at the right time, he would fall and block the train from killing the other five passengers. Of course, the fat man would not survive the fall, let alone being run over by a train.

You also realise, that being young and fit, you are unable to stop the train with your own mass. Although the fat man is certainly big enough to stop a speeding train, you are altogether too small to make an impression, and would simply splat against the train’s windshield.

So… what do you do?

Do you push the fat man off the bridge, thus stopping the train? Or do you save the fat man, and doom the five people tied up on the track to certain death?

You might be disgusted by the choice: after all, there is something very deeply personal about pushing someone to their deaths. Or perhaps you simply see it as an ethical problem no different to pulling the lever in the first trolley problem. There is, after all, no real difference: in either case, one person dies so that five may live.

As I said earlier, it is interesting that most people when faced with the first trolley problem choose to pull the lever. However, when faced with the second trolley problem, most people do not push the fat man. Despite the fact that they seem to be equally good alternatives, very few people are willing to bodily push someone to their deaths.

So what does this tell us about how to be good? Depending on the kind of opinion you might have, you might see it as an argument in favour of thinking that murder, for any reason, is wrong. Now, this position – the deontological position – provides the same result in all similar cases: you would not pull the lever or push the fat man.

However, someone else might argue that letting five people die is as good as killing them. They might also say that it is better that more people live, so even if killing one person is murder, then letting five people die is also murder, just five times more of it. This position – the utilitarian position – also provides the same result in all similar cases: you would pull the lever, and you would also push the fat man to his messy death.

Finally, you might not agree with either position! Instead, you might say that it is more wrong to push someone to their death than to kill someone by pulling a lever. You might think that, for some reason, it is important that the lever is far away, or that in the first problem you are killing the single man with technology instead of your hands.

Not matter what the case, thought experiments like this help us to work how we can best be good. Because once you have a rule or a system in mind, you can start applying those rules to your everyday life. Thought experiments in action!

So have a think about it! But it’s pretty cool, huh?