Trolley Problem

What is the Trolley Problem?

The Trolley Problem is a question of ethics—the study of what is right and wrong. Picture a big, heavy trolley rolling quickly on train tracks. Ahead, there are five people tied up on the tracks who cannot move. The trolley will hit them if it stays on the same path. You are right next to a lever that can make the trolley switch to a different set of tracks, but there’s a catch: there is one person tied up on that alternative path. Now, the big question: Do you pull the lever to make the trolley switch tracks, saving the five people but causing it to hit the one person, or do you not touch the lever and let the trolley hit the five?

This challenge encourages us to explore what makes an action right or wrong. It brings us to think about whether it’s okay to step in and make something bad happen to prevent an even worse result, or if we should avoid getting involved, even though that means not stopping a foreseeable tragedy.


Understanding the Trolley Problem involves two core definitions:

1. Moral Dilemma: At its heart, the Trolley Problem is a moral dilemma—a situation where a person must choose between two difficult scenarios, each of which has a moral weight. In this case, the dilemma is about whether you should intervene in a way that you prevent the loss of five lives at the cost of one, or abstain from acting, leading to five people losing their lives.

2. Ethical Decision-Making: The Trolley Problem also forces us to face ethical decision-making. This is a fancy term for how we think and decide what is the right or wrong thing to do when our choices could hurt someone or have big impacts. The Trolley Problem asks us if it’s more ethical to actively prevent a greater harm at the cost of causing a smaller one, or if it’s better to not cause harm directly, even if that means a worse outcome will happen because we did nothing.


  • Sacrificing One for Many: If you are making food for a group of friends, and you only have enough for either one person to be fully satisfied or for everyone to have a small portion, choosing to spread the food evenly is like pulling the lever to save the five people. It’s about sharing the resources you have to benefit the greater number of people, even if it means that no one is fully satisfied.
  • Emergency Situations: Imagine a lifeguard has to decide between saving one swimmer who is close by or swimming farther out to save a group of three swimmers. Choosing the group aligns with the utilitarian view of the Trolley Problem—maximizing the number of people saved.
  • Giving to Charity: Deciding to donate to a charity that helps many people with a small benefit, as opposed to a charity that greatly helps a single individual, is another reflection of the Trolley Problem’s ethical considerations.
  • School Group Projects: When you have a group project, and one person isn’t contributing, sometimes the group decides to cover for that person to ensure everyone gets a good grade. In this way, most people benefit, somewhat similar to pulling the lever to save more lives, even though it’s unfair to the hardworking students.
  • Resource Allocation in Disaster: During a natural disaster, rescuers may have to decide where to send limited aid. Sending it to the location with more people in danger reflects the utilitarian aspect of the Trolley Problem, which aims to minimize overall harm.

Why is it Important?

This dilemma matters because it helps us understand how people think about tough choices. Most of us won’t ever face a runaway trolley, but life is full of hard decisions where we have to think about what’s best for the most people. It’s especially relevant when leaders or policy makers have to decide on things that will affect lots of people, like laws or how to spend public money. Also, the Trolley Problem comes into play with new technology like self-driving cars; these cars will have to be programmed to make decisions when accidents are about to happen. As we grow up and face more responsibilities, understanding how to make these tough decisions and what they say about our values can help us navigate the challenges we encounter.

For the average person, this problem pushes us to think about what we would actually do versus what we think we should do. We all feel things like fear or the desire to do right by others, and these feelings can sometimes disagree with rules or ideas about fairness. If we can understand the Trolley Problem, it can help us understand ourselves and others better, whether we’re deciding who should do chores at home or how we should act in more serious situations involving other people’s well-being.

Related Topics

  • Autonomous Ethics: This is the study of how machines, like robots or AI, should make moral decisions. It’s closely linked to the Trolley Problem because it involves programming machines to handle dilemmas where harm is inevitable, just as humans would.
  • Bioethics: This field of study looks at how we make decisions in medicine and biology, including who gets life-saving treatments when there’s not enough for everyone. Decisions like these are where the Trolley Problem’s ethical exploration goes from theoretical to very real.
  • Game Theory: Game theory involves mathematical models of conflict and cooperation between intelligent rational decision-makers. It connects to the Trolley Problem because it analyzes how people are likely to behave in situations where their actions will affect others.


In sum, the Trolley Problem asks us to weigh lives and decide between two undesirable choices. It teaches us about the nature of moral dilemmas, pitting the desire to do the least harm against the instinct to not cause harm explicitly. It shows up in daily life, from personal decisions to global policies, and influences how we design technology that has to make split-second choices. Although the Trolley Problem might feel like just a philosophical puzzle, it’s a reflection of real-world decision-making and ethics that impact how we live together and shape our future society.