Trolley Problem


Suppose there is a runaway trolley barreling down a train track towards four adult men tied to the main track and one adult man tied to a side track at a junction. If nothing is done than it will continue on this course and kill all four of those men. However, if you divert the lever than only one man will be killed. There is no third option; you can’t call for help, you can’t untie any of the men in time, you can’t derail the trolley, and shielding it with your own body won’t help. There is no uncertainty in the outcome either; the lever is 100% assured to work if you pull it and nothing is going to happen to stop the trolley. There is also no way to get all five men out of the situation alive; somebody is going to be dead no matter what you choose.

The Trolley Problem has countless variations but the underlying question is the same; Is it better to do harm knowing your action will minimize the total amount of harm, or is it better to not do harm knowing your inaction will maximize the total amount of harm?

Some (myself included) belief that the former is better because it results in the least number of deaths, arguing that there is little moral difference between doing harm by action and by allowing harm by inaction. Others believe that that the latter is better because harm is not resulting from your action, arguing that there is great moral difference between doing harm by action and allowing harm by inaction.

What do you think? Whichever you think is better, please be respectful and civil.


There are two problems I see here:

  1. Assuming you are not the reason the trolly is heading to them, by actively making a choice you are playing God over who lives and who dies.

  2. actively choosing to save the 4 is the “right decision” if there is no afterlife. If you don’t believe in an afterlife, saving the 4 is a no brainer. But if you believe in Heaven, you have faith that God will grant Mercy and that whomever dies will be in a better place.

The best answer is to not make a choice and do your best to save everyone, even if you fail.


I would try to repair the brake lever and stop the train so that no one will be killed.


We always “play” God when there are fewer ampoules of antidote than patients who need them.

You talk as if you had actual information about God’s actions. You do not.

No “active” action is still a choice. Just sayin’.


The problem is that not pulling the lever IS a choice, it is choosing inaction. I’ll feel just as responsible for letting four people die whom I could have saved as I would feel if I outright killed one person to save four others.

Refusing to make a painful decision to prevent four deaths, just to prevent one death from being the result of my direct action, feels (to me at least) like Pontius Pilate trying to wash his hands.


You’re not on the train. You are next to the train tracks, and your lever only controls the junction.


The principle of double effect.
That’s the Catholic answer to this kind of problem.

What is double effect? It is a principle which explains that we can choose to do something which has both a good and evil effect, given certain conditions:
*]The act which you do must, in itself, be morally good or neutral. You cannot do an evil act to bring about some good effect.
*]The good effect of your act must be greater than the evil effect, AND there must be sufficient reason to cause the two effects at all.
*]You must NOT will the evil effect directly. You must will the good effect only, and tolerate the evil effect.

If those three conditions are met, you can make the choice between the two options, choosing the choice that brings about the most good.

The answer to the current hypothetical is that you MAY flip the lever, intending to save the 4 people. You are, of course, sad that one person will still die, but you are acting to save the 4.
*]The act itself is morally neutral (flipping a lever)
*]The good effect is greater than the evil effect (good effect: saving 4 people; evil effect: killing 1 person)
*]You intend only the good effect.

To be clear, another option that would also be permissible is to do nothing. If in those moments you were unable to determine the moral course of action, no sin of omission would be committed by doing nothing.

These questions and others relating to the idea of “choose the lesser of two evils” (which is a WRONG moral principle, by the way) are discussed in this thread here.


Wow, the Church thinks of everything doesn’t it?


I would try to jump on the train and brake it to a stop so that no one would be killed.


You divert it, unless there is something extraordinary about the individuals who are involved.


She sure does. :smiley:


Me too. Till I realized that action could not succeed. What would be the best course now? Flip the lever, or leave it alone?


Though weighing up factors and balancing them against a body count is difficult.


I would keep trying to save everyone by stopping the train or some other action. I would never despair and give up hope. I would pray to the Lord to help me find a solution to save everyone. With the Lord’s help and support, I have faith and I have hope that I could find a way to stop the train in time to save everyone and no one would be hurt.


Certainly, if you were unable to see that only 4 could be saved, and thus failed to act accordingly, you would not be condemned for failing to save lives. You may later feel some remorse for not acting to save the 4 though.


You explained this FAR better than me. :thumbsup:


I have faith in the Lord. As Our Divine Lord has said perhaps some people do not have enough faith?
Matthew 17:20 ““You don’t have enough faith,” Jesus told them. “I tell you the truth, if you had faith even as small as a mustard seed, you could say to this mountain, ‘Move from here to there,’ and it would move. Nothing would be impossible.””
Now if we have faith, we can move a mountain. How much easier would it be to jump on a train and apply the brakes or to find an alternate way to stop a train, than it would be to move Mount Everest to a location near Palm Springs California?
You must have the faith and the hope to succeed in saving these unfortunate people by stopping the train. Do not despair and do not give up. Surely, with faith and hope in the Lord, a way can be found to make the brake work and stop the train.
If faith as small as a mustard seed (which is very small by the way) can move mountains, then why can’t our strong faith prevent a train from killing innocent people?


For those of us without such powerful faith Tom, we must fall back on our reason to discern the well-intentioned, good act that leads to the least harm.


Yes. It takes practical wisdom. Some are easier than others… Do I save the philosopher king, or 4 notorious reprobates?


If James Bond can perform stunts like this, it is only reasonable that with a small amount of faith, equal to that of a mustard seed, I can also succeed to stop the train in time to save everyone. I would work to save everyone involved, so that no one would be hurt in the slightest.

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