Double effect and causal remoteness

I think some people feel that more immediate effects count for more than more remote ones in moral choices, including in the context of the Principle of Double Effect. I used to think this is wrong, as long as the probabilities of effects are the same (typically more remote effects are more uncertain, but we can easily imagine cases where this is not so). But then I thought of two strange trolley cases.

In both cases, the trolley is heading for a track with Fluffy the cat asleep on it. The trolley can be redirected to a second track on which an innocent human is sleeping. Moreover, in a nearby hospital there are five people who will die if they do not receive a simple medical treatment. There is only one surgeon available.

But now we have two cases:

1. All five people love Fluffy very much and have specified that they consent to life-saving treatment if and only if Fluffy is alive. The surgeon refuses to perform surgery that the patients have not consented to.

2. The surgeon loves Fluffy and after hearing of the situation has informed you that they will perform surgery if and only if Fluffy is alive.

In both cases, I am rather uncomfortable with the idea of redirecting the trolley. But if we don’t take immediacy into account, both cases seem straightforward applications of Double Effect. The intention in both cases is to save five human lives by saving Fluffy, with the death of the person on the second track being an unintended side-effect. Proportionality between the good and the bad effects seems indisputable.

However, in both cases, redirecting the trolley leads much more directly to the death of the one person than to the saving of the five. The causal chain from redirection to life-saving in both cases is mediated by the surgeon’s choice to perform surgery. (In Case 1, the surgeon is reasonable and in Case 2, the surgeon is unreasonable.) So perhaps in considerations of proportionality, the more immediate but smaller bad effect (the death of the person on the side-track) outweighs the more remote but larger good effect (the saving of the five).

I can feel the pull of this. Here is a test. Suppose we make the death of the sixth innocent person equally indirect, by supposing instead that Rover the dog is on the second track, and is connected to someone’s survival in the way that Fluffy is connected to the survival of the five. In that case, it seems pretty plausible that you should redirect. (Though I am not completely certain, because I worry that in redirecting the trolley even in this case you are unduly cooperating with immoral people—the five people who care more about a cat than about their own human dignity, or the crazy surgeon.)

If this is right, how do we measure the remoteness of causal chains? Is it the number of independent free choices that have to be made, perhaps? That doesn’t seem quite right. Suppose that we have a trolley heading towards Alice who is tied to the track, and we can redirect the trolley towards Bob. Alice is a surgeon needed to save ten people. Bob is a surgeon needed to save one. However, Alice works in a hospital that has vastly more red tape, and hence for her to save the ten people, thirty times as many people need to sign off on the paperwork. But in both cases the probabilities of success (including the signing off on the paperwork) are the same. In this case, maybe we should ignore the red tape, and redirect?

So the measure of the remoteness of causal chains is going to have to be quite complex.

All this confirms my conviction that the proportionality condition in Double Effect is much more complex than initially seems.

Two looping trolley scenarios

As part of an argument against the Principle of Double Effect, Thomson argued that if one thinks that it is permissible to redirect a trolley that is heading towards a branch with five people (“Branch” in my diagram) so it heads on a branch towards one, then this redirection remains permissible if one adds a looping track to the right branch that comes back to the left branch, as long as the one person on the right branch is large enough to stop the trolley from hitting the five.

But, Thomson insists, in the looping case the trolley’s hitting the large person on the right branch is a means to the five being saved, and so the defender of Double Effect cannot hold that there is something especially bad about intentionally harming someone.

Subsequently, it’s been noted, implicitly or explicitly (Liao et al.) that there is an ambiguity in Thomson’s story. On one version, “SymLoop” in my diagram, the track becomes symmetric, so that just as the one would block the trolley from hitting the five if the trolley went to the right branch, the five would block the trolley from hitting the one if the trolley stayed on the left branch. On the other hand, in AsymLoop, the left branch continues on, and if the trolley were to go on the left branch without the five being there, inertia would carry it harmlessly forward and away from everyone concerned.

When talking about all looping trolleys with Harrison Lee, it has occurred to me that there is a not implausible view on which:

1. Redirection in Branch is permissible.

2. Redirection in SymLoop is permissible.

3. Redirection in AsymLoop is impermissible.

Here is why. In Branch, we have the standard Double Effect considerations, which I won’t rehearse.

Now, redirecting in AsymLoop is morally the same as a case where a trolley is heading down a straight unbranching path towards five people, and you grab a random large bystander and push them in front of the trolley to save the five (call this “Bystander Push”). For in both AsymLoop and Bystander Push, you are interposing a bystander between the trolley and the five. The only difference is the mechanics of who or what is moved (and motion is relative anyway). And most non-utilitarians agree that pushing the bystander in front of the trolley is wrong.

However, SymLoop is a bit different. Here we have six people towards whom a dangerous trolley is heading, and we try to rearrange the six people in danger in such a way that as few of them die as possible. What is analogous to SymLoop is not Bystander Push, but a case where the trolley is heading down a single straight path in a narrow tunnel (so narrow that stepping off the track won’t save one), on which there are five small people just in front of one large person, and we reorder the large person to be in front of the small ones. Call this Reorder Push.

I think there is good reason to think Reorder Push is permissible. We have a group in danger. By chance, the status quo is that the five small people are protecting the large person. But is that fair? They are smaller in body, but no smaller in dignity. If they were all the same size, so that no matter what order they were in, the same number would die, it would be fair to roll dice to figure out the order—or to just count the status quo as “the dice having already been rolled”. But when they are not the same size, there is a naturally preferred arrangement of the people in danger: the large one first, and then the small ones. (For a variant case, suppose the six people are all standing in a line in the tunnel perpendicular to the track, so that when the trolley comes, they all will die. It would be perfectly reasonable for the five small ones to move behind the one large one, and utterly unreasonable for the large one to move behind the five small ones—the large person shouldn’t get defended at the expense of five.)

If Reorder Push is permissible, so is redirection in SymLoop. In both cases, the trolley is heading towards six, and we are just rearranging.

Now, it may seem that the reasoning behind Reorder Push should be rejected by a non-consequentialist. But I don’t think so. Prior to learning of Thomson’s Loop case (and hence not in order to generate a response to Loop), I wrote a paper on Double Effect where using an idea of Murphy’s I defend a distinction between accomplishing someone’s death and accomplishing someone’s being in lethal danger. On the view I defend, it’s always wrong to accomplish someone’s death, at least under such conditions as juridical innocence, but accomplishing someone’s being endangered, even lethally, is not always wrong. In particular, it’s not always wrong when the person consents to it, or when one has appropriate authority over the person. Thus, just as it is permissible to jump on a grenade to save comrades, it is permissible to push someone on a grenade with with their consent (suppose that the hero is unable to themselves jump, and the person pushing the hero is unable to reach the grenade with their own body), and it may be permissible for an officer to push a non-consenting soldier onto the grenade.

Now, the trolley case is not a case of intentional killing but of intentionally setting up a situation that in fact has lethal danger in it. One does not intend the death of the one in redirecting the trolley, but instead one intends the absorption of kinetic energy—which absorption happens to be a lethal danger to the absorber. This is not absolutely morally forbidden, but is only forbidden in some cases. In particular, it is not forbidden in cases of consent. That’s why pushing a random bystander is wrong, but it is not wrong to push a volunteer who is otherwise unable to move. In the same way, redirection in either SymLoop or AsymLoop would be permissible with the consent of the large person on the right track. But as the case is normally set up, you don’t have this consent.

Now, without the consent of the large person, AsymLoop and SymLoop come apart, as do Bystander and Reorder Push. Grabbing someone towards whom the trolley is not heading, and putting them in front of the trolley, whether by pushing (Bystander Push) or by moving the trolley (AsymLoop) is a wrongful case of accomplishing their lethal endangerment. But when that person happens to be in the lucky status quo where they are in the path of the trolley, but are being protected by the bodies of the five, they ought to refuse that costly protection. They ought in justice to consent to reordering or redirection. Now, in some cases, actual consent and obligation-in-justice to consent have different moral effects (e.g., in sexual cases the difference is very significant), but in other cases they may have similar moral effects. It is quite reasonable to say that in endangerment cases, actual consent and obligation to consent have similar moral effects. (One hint of this is that endangerment cases are ones where authority can have an effect to consent; sexual cases, for instance, are not like that—authority does nothing in the absence of consent there.) Thus, even without consent, redirection in SymLoop is permissible—but not so in AsymLoop.

Final remark: I wonder if it matters whether it is justice or something else that requires the consent in these kinds of cases. Intuition: One has a moral duty to jump in front of a trolley that is heading towards a hundred (but mabe not towards five) people. If so, and if it doesn’t matter whether the obligation is in justice or in some other way (say, charity), then once enough lives come to be at stake, then redirection in AsymLoop and pushing the non-consenting bystander become permissible. But if the obligation has to be one of justice, then one might hold that the redirection and pushing remains wrong even when there are more lives at stake.

Acknowledgment: The thinking here is greatly influenced by arguments from Harrison Lee about volunteering in loop trolley cases, but the conclusions differ.

Doing, allowing and trolleys

Consider a trolley problem where the trolley is heading for:

• Path A with two people,

but you can redirect it to:

• Path B with one person.

If that’s the whole story, and everyone is a stranger to you, redirection is surely permitted, and probably even required.

But add one more ingredient: the one person on Path B is you yourself. I am far from sure of this, but I suspect that you aren’t morally required to save two strangers at the expense of your life, though of course it would be praiseworthy if you did. (On the other hand, once the number on Path A is large enough, I think it becomes obligatory to save them.)

Now consider a reverse version. Suppose that the trolley is heading for Path B, where you are. Are you permitted to redirect it to Path A? I am inclined to think not.

So we have these two judgments:

1. You aren’t obligated to redirect from two people to yourself.

2. You aren’t permitted to redirect from yourself to two people.

This suggests that in the vicinity of the Principle of Double Effect there is an asymmetry between doing and allowing. For you are permitted to allow two people to be hit by the trolley rather than sacrifice your life, but you are not permitted to redirect the trolley from yourself to the two.

Now, you might object that the whole thing here is founded on the idea, which I am not sure of, that you are not obligated to save two strangers at the expense of your life. While I am pretty confident that you are not obligated to save one stranger at the expense of your life, with two I become unsure. If this is the sticking point, I can modify my case. Instead of having two people fully on Path A, we could suppose that there is one person fully on Path A and the other has a limb on the track. I don’t think you are obligated to sacrifice your life to save one stranger’s life and another’s limb. But it still seems wrong to redirect the trolley from yourself at the expense of a stranger and a limb. So we still have an allowing-doing asymmetry.

Another interesting question: Are you permitted to redirect a trolley heading for you in a way that kills one stranger? I am not sure.

Double Effect and trivially good ends

Suppose I am facing the classic trolley situation: a trolley is hurtling towards five persons on the left track, but I can redirect the trolley onto the right track where there is only one person.

A normal decent person will redirect the trolley in order to save the five persons, tolerating the unintended death of the one person as a side-effect. But now imagine that Alice redirects the trolley solely in order to enjoy the feeling of moving the railway switch. She realizes that this spells the death of the person on the right track. But she reasons as follows:

I am not intending the death of that person. I am intending the pleasant feeling of moving the railway switch. I foresee the death of one person on the right track. However, the overall foreseen consequences of the action are positive: five live, one dies and I have fun, instead of five dying and one living. Thus the Principle of Double Effect applies. I am aiming at a good (fun), with the bad effect (death of one) not intended as either an end or as a means, and the good effect is proportionate to the overall consequences, since the overall consequences are positive.

There is something with Alice’s failure to intend to save the lives of the five. What is wrong? Here is one suggestion:

1. In the proportionality condition of the Principle of Double Effect, we do not simply compare the good and the bad effects, but we compare the intended good effects to all the foreseen bad effects.

In the case of a normal decent person, saving the five persons is intended, and proportionality holds. But Alice doesn’t intend to save the five and so there is no proportionality.

I am inclined to think the suggested proportionality condition asks for too much. Suppose Bob is an agent much like in the original trolley situation, except that he is tied down, near the switch, in such a way that his leg protrudes onto the left track after the switch. Bob is (rightly) terrified of getting his leg amputated, and decides to redirect the trolley. He then notices that on the right track there is a person, and so if he redirects the trolley, that person will die. He is about to resign himself to loss of the leg, when he looks at the left track and notices that there are five people there. He reasons that while a person will die, on balance the consequences of redirecting are good, and redirects the trolley solely in order to save his leg.

While we would prefer it if Bob intended to save the five people on the left track, I do not think Bob did anything wrong. What was wrong with Alice’s action was that her end, the pleasure of flipping the switch, was execrably trivial in comparison to the death of the person on the right track. Bob’s end is far from trivial. Thus, I suggest:

2. In the proportionality condition of the Principle of Double Effect, we do two comparisons. First, we ensure that the intended good effects are not trivial in comparison to all the foreseen bad effects. Second, we ensure that the foreseen good effects are proportionate to the foreseen bad effects.

The five-five trolley

The standard trolley case is where a trolley is heading to a track with five people, and you can redirect it to a track with one person. It seems permissible to do so.

But now imagine that a trolley is heading to a track with five people, and you can redirect it to another track also with five people. Why would you bother? Well, suppose that you enjoy turning the steering wheel on the trolley, and you reason that there is no overall harm in your redirecting the trolley.

This seems callous.

Yet we are in cases like the five-five trolley all the time. By the butterfly effect, many minor actions of ours affect the timings of human mating (you have a short conversation with someone as they are leaving work; this affects traffic patterns, and changes the timing of sexual acts for a number of people in the traffic), which then changes which sperm reaches an ovum, and hence affects which human beings exist in the next generation, and the changes balloon, and pretty soon there are major differences as to who is in the path of a hurricane, and so on.

But of course there is still a difference between the five-five trolley and the butterfly effect cases. In the five-five trolley, you know some of the details of the effects of your action: you know that these five will die if you don’t redirect and those five if you do. But note that these details are not much. You still may not know any of the ten people from Adam. In the butterfly effect cases, you can say a fair amount about the sort of effects your minor action has, but not much more than that.

What’s going on? I am inclined to think that here we should invoke something about the symbolic meaning of one’s actions. In the case where one turns the steering wheel on the trolley for fun, while knowing epistemically close effects, one exhibits a callous disregard for the sanctity of human life. But when one has a conversation with someone after work, given the epistemic distance, one does not exhibit the same callous disregard.

It is not surprising if callousness and regard for sacredness should depend on fine details of epistemic and other distance. Think of the phenomenon of jokes that come “too soon” after a terrible event: they show a callous disregard for evil. But similar jokes about temporally, personally and/or epistemically distant events may be acceptable.

Probabilistic trolleys

Suppose a trolley is heading towards five people, and you can redirect it towards one. But the trolley needs to go up a hill before it can roll down it to hit the five people, and your best estimate of its probability of making it up the hill is 1/4. On the other hand, if you redirect it, it’s a straight path to the one person, who is certain to be killed. Do you redirect? Expected utilities:  − 1.25 lives for not redirecting and  − 1 lives for redirecting.

Or suppose you are driving a fire truck to a place where five people are about to die in a fire, and you know that you have a 1/4 chance of putting out the fire and saving them if you get there in time. Moreover, there is a person sleeping on the road in front of the only road to the fire, and if you stop to remove the person from the road, it will be too late for the five. Do you brake? Expected utilities:  − 5 lives for braking and  − 1 − 3.75 =  − 4.75 lives for continuing to the fire and running over the person on the road.

I think you shouldn’t redirect and you should brake. There is something morally obnoxious about certainly causing death for a highly uncertain benefit when the expected values are close. This complicates the proportionality condition in the Principle of Double Effect even more, and provides further evidence against expected-value utilitarianism.

Probabilistic trolleys

Generally people think that if a trolley is heading for a bunch of people, it’s wrong to push an innocent bystander in front of the trolley to stop it before it kills the other people, with the innocent bystander dying from the impact.

But imagine that it is 99% likely that the bystander will survive the impact, but 100% certain that the five people further down the track would die. Perhaps the trolley is accelerating downhill, and currently it only has a 1% chance of lethality, but by the time it reaches the five people at the bottom of the hill, it has a 100% chance of lethality. Or perhaps the five people are more fragile, or the bystander is well-armored. For simplicity, let’s also suppose that the trolley cannot inflict any major injury other than death. At this point, it seems plausible that it is permissible to push the bystander in front of the trolley.

But now let’s suppose the situation is repeated over and over, with new people at the bottom of the track but the same unfortunate bystander. Eventually the bystander dies, and the situation stops (maybe that death is what convinces the railroad company to fix the brakes on their trolleys). We can expect about 500 people to be saved at this point. However, it seems that in the case where the bystander wasn’t going to survive the impact, it would have been wrong to push them even to save 500.

There are at least two non-consequentialist ways out of this puzzle.

1. It is wrong to push the bystander in front of the trolley in the original case where doing so is fatal. After all, one is not intending the bystander’s death, but only their absorption of kinetic energy. In my 2013 paper, I argued that this constitutes wrongful lethal endangerment when the bystander does not consent, even if it is not an intentional killing. But perhaps that judgment is wrong.

2. It is wrong to push the bystander to save five, but not wrong to push them to save five hundred. While this is a special case of threshold deontology, one can make this move without embracing threshold deontology. One can say that no matter how many are saved, it is wrong to intentionally kill the innocent bystander, but lethal endangerment becomes permissible once the number of people saved is high enough.

Initially, I also thought the following was an appealing solution: It matters whether it is the same bystander who is pushed in front of the trolley each time or a different one. Pushing the same bystander repeatedly unjustly imposes a likely-lethal burden on them, and that is wrong. But it would be permissible to push a different bystander each time onto the track, even though it is still almost certain that eventually a bystander will die. The problem with this solution is this. When the sad situation is repeated with different bystanders, by adopting the policy of pushing the bystander, we are basically setting up a lethal lottery for the bystanders—one of them will be killed. But if we can do that, then it seems we could set up a lethal lottery a different way: Choose a random bystander out of, say, 500, and then keep on pushing that bystander. (Remember that the way the story was set up, death is the only possible injury, so don’t think of that bystander as getting more and more bruised; they are unscathed until they die.) But that doesn’t seem any different from just pushing the same bystander without any lottery, because it is pretty much random which human being will end up being the bystander.

More on proportionality in Double Effect and prevention

In my previous post, I discuss cases where someone is doing an evil for the sake of preventing significantly worse goods—say, murdering a patient to save four others with the organs from the one—and note that a straightforward reading of the Principle of Double Effect’s proportionality condition seems to forbid one from stopping that evil. I offer the suggestion, due to a graduate student, that failure to stop the evil in such cases implies complicity with the evils.

I now think that complicity doesn’t solve the problem, because we can imagine case where there is no relevant evildoer. Take a trolley problem where the trolley is coming to a fork and about to turn onto the left track and kill Alice. There is no one on the right track. So far this is straightforward and doesn’t involve Double Effect at all—you should obviously redirect the trolley. But now add that if Alice dies, four people will be saved with her organs, and if Alice lives, they will die.

Among the results of redirecting the trolley, now, are the deaths of the four who won’t be saved, and hence Double Effect does apply. To save one person at the expense of four is disproportionate, and so it seems that one violates Double Effect in saving the one. And in this case, a failure to save Alice would not involve any complicity in anyone else’s evildoing.

It is tempting to say that the deaths of the four are due to their medical condition and not the result of trolley redirection, and hence do not count for Double Effect proportionality purposes. But now imagine that the four people can be saved with synthetic organs, though only if the surgery happens very quickly. However, the only four surgeons in the region are all on an automated trolley, which is heading towards the hospital along the left track, is expected to kill Alice along the way, but will continue on until it stops at the hospital. If the trolley is redirected on the right path, it will go far away and not reach the hospital in time.

In this case, it does seem correct to say that Double Effect forbids one from redirecting the trolley—you should not stop the surgeons’ trolley even if a person is expected to die from a trolley accident along the way. (Perhaps you are unconvinced if the number of patients needing to be saved is only four. If so, increase the number.) But for Double Effect to have this consequence, the deaths of the of the patients in the hospital have to count as effects of your trolley redirection.

And if the deaths count in this case, they should count in the original case where Alice’s organs are needed. After all, in both cases the patients die of their medical condition because the trolley redirection has prevented the only possible way of saving them.

Here’s another tempting response. In the original version of the story, if one refrains from redirecting the trolley in light of the people needing Alice’s organs, one is intending that Alice die as a means to saving the four, and hence one is violating Double Effect. But this response would not save Double Effect: it would make Double Effect be in conflict with itself. For if my earlier argument that Double Effect prohibits redirecting the trolley stands, and this response does nothing to counter it, then Double Effect both prohibits redirecting and prohibits refraining from redirecting!

I think what we need is some careful way of computing proportionality in Double Effect. Here is a thought. Start by saying in both versions of the case that the deaths of the four patients are not the effects of the trolley redirection. This was very intuitive, but seemed to cause a problem in the delayed-surgeons version. However, there is a fairly natural way to reconstrue things. Take it that leaving the trolley to go along the left track results in the good of saving the four patients. So far we’ve only shifted whether we count the deaths of the four as an evil on the redirection side of the ledger or the saving of the four as a good on the non-redirection side. This makes no difference to the comparison. But now add one more move: don’t count goods that result from evils in the ledger at all. This second move doesn’t affect the delayed-surgeons case. For the good of saving lives in that case is not a result of Alice’s death, and the proportionality calculation is unaffected. In particular, in that case we still get the correct result that you should not redirect the trolley, since the events relevant to proportionality are the evil of Alice’s death and the good of saving four lives, and so preventing Alice’s death is disproportionate. But in the organ case, the good of saving lives is a result of Alice’s death. So in that case, Double Effect’s proportionality calculation does not include the lives saved, and hence, quite correctly, we conclude that you should redirect to save Alice’s life.

Maybe. But I am not sure. Maybe my initial intuition is wrong, and one should not redirect the trolley in the organ case. What pulls me the other way is the hungry bear case here.

Trolleys and chaos

Suppose that determinism is true and Alice is about to roll a twenty-sided die to determine which of twenty innocent prisoners to murder. There is nothing you can do to stop her. You are in Alice’s field of view. Now, a die roll, even if deterministic, is very sensitive to the initial conditions. A small change in Alice’s throw is apt to affect the outcome. And any behavior of yours is apt to affect Alice’s throw. You frown, and Alice becomes slightly tenser when she throws. You smile, and Alice pauses a little wondering what you’re smiling about, and then she throws differently. You turn around not to watch, and Alice grows annoyed or pleased, and her throw is affected.

So it’s quite reasonable to think that whatever you do has a pretty good chance, indeed close to a 95% chance, of changing which of the prisoners will die. In other words, with about 95% probability, each of your actions is akin to redirecting a trolley heading down a track with one person onto a different track with a different person.

Some people—a minority—think that it is wrong to redirect a trolley heading for five people to a track with only one person. I wonder what they could say should be done in the Alice case. If it’s wrong to redirect a trolley from five people to one person, it seems even more wrong to redirect a trolley from one person to another person. So since any discernible action is likely to effectively be a trolley redirection in the Alice case, it seems you should do nothing. But what does “do nothing” mean? Does it mean: stop all external bodily motion? But stopping all external bodily motion is itself an effortful action (as anybody who played Lotus Focus on the Wii knows). Or does it mean: do what comes naturally? But if one were in the situation described, one would likely become self-conscious and unable to do anything “naturally”.

The Alice case is highly contrived. But if determinism is true, then it is very likely that many ordinary actions affect who lives and who dies. You talk for a little longer to a colleague, and they start to drive home a little later, which has a domino effect on the timing of people’s behaviors in traffic today, which then slightly affects when people go to sleep, how they feel when they wake up, and eventually likely affects who dies and who does not die in a car accident. Furthermore, minor differences in timing affect the timing of human reproducive activity, which is likely to affect which sperm reaches the ovum, which then affects the personalities of people in the next generation, and eventually affects who lives and who dies. Thus, if we live in a deterministic world, we are constantly “randomly” (as far as we are concerned, since we don’t know the effects) redirectly trolleys between paths with unknown numbers of people.

Hence, if we live in a deterministic world, then we are all the time in trolley situations. If we think that trolley redirection is morally wrong, then we will be morally paralyzed all the time. So, in a deterministic world, we better think that it’s OK to redirect trolleys.

Of course, science (as well as the correct theology and philosophy) gives us good reason to think we live in an indeterministic world. But here is an intuition: when we deal with the external world, it shouldn’t make a difference whether we have real randomness or the quasi-randomness that determinism allows. It really shouldn’t matter whether Alice is flipping an indeterministic die or a deterministic but unpredictable one. So our conclusions should apply to our indeterministic world as well.

Triple effect, looping trolley and felix culpa

Frances Kamm uses her principle of triple effect to resolve the loop version of the trolley problem. On the loop version, as usual, the main track branches into are two tracks, track A with five people and track B with one person, and the trolley is heading for track A. But now the two tracks join via a loop, so if there were no one on either track, a trolley that goes on track A will come back on track B and vice versa. If we had five people on track A and no one on track B, and we redirected the trolley to track B, it would go on track B, loop around, and fatally hit the people on track A anyway. But the one person actually on track B is big enough that if the trolley goes on track B, it will be stopped by the impact and the five people will be saved.

The problem with redirecting to track B on the loop version of the trolley problem is that it seems that a part of your intention is that the trolley should hit the person on track B, since it is that impact which stops the trolley from hitting the five people on track A. And so you are intending harm to the person on track B.

In her Intricate Ethics book, Kamm gives basically this story about redirecting the trolley in the loop case:

• Initial Intention: Redirect trolley to track A to prevent the danger of five people being hit from the front.

• Initial Defeater: The five people come to be in danger of being hit from the back by the trolley.

• Defeater to Initial Defeater: The one person on track B blocks the trolley and prevents the dangers of being hit from the back.

The important point here is that the defeater to the defeater is not intended—it is just a defeater to a defeater. Thus there is no intention to block the trolley via the one person on track B, and hence that person’s being hit is not a case of their intentionally being used as a means to saving lives.

But this defeater-defeater story is mistaken as it stands. For given the presence of the person on track B, there is no danger of the five people being hit from the back. Thus, there is no initial defeater here.

Now, if you don’t know about the one person on track B, you would have a defeater to the redirection, namely the defeater that there is danger of being hit from the back. But learning about the person on track B would not provide a defeater to that defeater—it would simply remove the defeater by showing that the danger doesn’t exist.

That the story doesn’t have a defeater-defeater structure does not mean that one is intending the one person to be hit. Kamm might still be right in thinking there is no intention to block the trolley via the one person on track B. But I am dubious of Kamm’s story now, because I am dubious that the danger of being hit from the front yields a worthy initial intention. For there is nothing particularly bad about being hit from the front. It is only the danger of being hit simpliciter that seems worth preventing.

It is interesting to me to note that even if Kamm’s story doesn’t have defeater-defeater form, the main place where I want to use her triple effect account seems to still have defeater-defeater form. That place is the felix culpa, where God allows Adam and Eve to exercise their free will, even though he knows that this would or might well (depending on details about theories of foreknowledge and middle knowledge) result in their sinning, and God’s reasoning involves the great goods of salvation history that come from Adam and Eve’s sin.

• Initial Intention: Allow Adam and Eve to exercise their free will.

• Initial Defeater: They will or might well sin.

• Defeater to Initial Defeater: Great goods will come about.

Here the initial defeater is not mistaken as in the looping trolley case—the sin or its possibility is really real. Moreover, while it’s not an initially worthy intention to prevent people from being hit from the front, unless they aren’t going to be hit from behind (or some other direction) either, it is an initially worthy intention to allow Adam and Eve to exercise their free will, even if no further goods come about, because free will is intrinsically good.

Thus we can criticize Kamm’s own use of triple effect while yet preserving what I think is a really important theological application.

Doing and refraining, and proportionality

In my previous post, I suggested that proportionality considerations in Double Effect work differently for positive actions (doings) than for negative ones (refrainings). One thing that is now striking me is that there is an interesting asymmetry with respect to relational features that is brought out by thinking about pairs of trolley cases with different groups of people on the two tracks, but where we vary which track the trolley is initially heading for.

For an initial pair of cases, suppose on one track is someone one has a close relationship with (one’s child, spouse, parent, sibling, close friend, etc.)—“friend” is the term I will use for convenience—and on the other track a stranger. Then:

• It’s completely clear that if the trolley is heading for the stranger, it is permissible not to redirect the trolley

• It’s significantly less clear but plausible that if the trolley is heading for the friend, it is permissible to redirect the trolley.

In this case, I already feel a moral difference between doing, i.e., redirecting the trolley, and refraining, i.e., leaving the trolley be, even though my permissibility judgment is the same in the two cases: redirecting the trolley towards the stranger and allowing the trolley to hit the stranger are both permissible. And yet regardless of where the trolley is initially heading, there are the same two outcomes: either a stranger dies or a friend dies. The difference between the cases seems to be solely grounded in which outcome is produced by doing (redirecting) and which by refraining (not redirecting).

Suppose we vary the ratio of strangers to friends in this case. At a 2:1 ratio of strangers to friends, my intuitions say:

• It’s very plausible that if the trolley is heading for the strangers, it is permissible not to redirect the trolley

• I can’t tell whether if the trolley is heading for the friends, it is permissible to redirect the trolley.

As the ratio of strangers to friends increases, my intuition shifts in favor of saving the greater number of strangers. But, nonetheless, my intuition consistently favors saving the strangers more strongly when this is done by refraining-from-redirecting than when this is done by redirecting. Thus, even at a 10:1 ratio of strangers to friends:

• It’s almost completely clear that if the trolley is heading for the strangers, it is morally required to redirect

• It’s completely clear that if the trolley is heading for the friends, it is morally forbidden to redirect.

In fact, I think there are points where the ratio of strangers to friends is both sufficiently high that:

• If the trolley is heading for the friends, it is forbidden to redirect

and yet still sufficiently low that:

• If the trolley is heading for the strangers, it is not required to redirect.

I feel that 3:2 may be such a ratio, though the details will depend on the exact nature of one’s relationship with the friends.

These cases suggest to me that the proportionality requirements governing refrainings and doings are different. It is consistently easier to justify refraining from redirect than to justify redirecting even when the consequences are the same. Nonetheless, even though the proportionality requirements are different, in the cases above they do not look qualitatively different, but only quantitatively so.

Mystery and religion

Given what we have learned from science and philosophy, fundamental aspects of the world are mysterious and verge on contradiction: photons are waves and particles; light from the headlamp on a fast train goes at the same speed relative to the train and relative to the ground; objects persist while changing; we should not murder but we should redirect trolleys; etc. Basically, when we think deeper, things start looking strange, and that’s not a sign of us going right. There are two explanations of this, both of which are likely a part of the truth: reality is strange and our minds are weak.

It seems not unreasonable to expect that if there were a definitive revelation of God, that revelation would also be mysterious and verge on contradiction. Of the three great monotheistic religions, Christianity with the mystery of the Trinity is the one that fits best with this expectation. At the same time, I doubt that this provides much of an argument for Christianity. For while it is not unreasonable to expect that God’s revelation would be paradoxical, it is a priori a serious possibility that God’s revelation might be so limited that what was revealed would not be paradoxical. And it would also be a priori a serious possibility that while creation is paradoxical, God is not, though this last option is a posteriori unlikely given what we learn from the mystical experience traditions found in all the three monotheistic religions.

So, I am not convinced that there is a strong argument for Christianity and against the other two great monotheistic religions on the grounds that Christianity is more mysterious. But at least there is no argument against Christianity on the basis of its embodying mysteries.

Cupcakes and trolleys

A trolley is heading towards a person lying on the tracks. Also lying on the tracks is a delicious cupcake. You could redirect the trolley to a second track where there is a different person lying on the tracks, but no cupcake.

Utilitarianism suggests that, as long as you are able to enjoy the cupcake under the circumstances and not feel bad about the whole affair, you have a moral duty to redirect the trolley in order to save the cupcake for yourself. This is morally perverse.

Besides showing that utilitarianism is false, this example shows that the proportionality condition in the Principle of Double Effect cannot simply consist in a simple calculation comparing the goods and bads resulting from the action. For there is something morally disproportionate in choosing who lives and dies for the sake of a cupcake.

Four plausibilistic arguments for redirecting the trolley

Start with the standard scenario: trolley speeding towards five innocent strangers, and you can flip a lever to redirect it to a side-track with only one innocent stranger. Here are four arguments each making it plausible that redirecting the trolley is right. [Unfortunately, as you can see from the comments, the first three arguments, at least, are very weak. - ARP]

1. Back and forth: Suppose there is just enough time to flip the lever to redirect and then flip it back--but no more time than that. Assuming one shouldn't redirect, there is nothing wrong with flipping the lever if one has a firm plan to flip it back immediately. After all, nobody is harmed by such a there-and-back movement. The action may seem flippant (pun not intended--I just can't think of a better term), but we could suppose that there is good reason for it (maybe it cures a terrible pain in your arm). But now suppose that you're half-way through this action. You've flipped the lever. The trolley is now speeding towards the one innocent. At this point it is clearly wrong for you to flip it back: everyone agrees that a trolley speeding towards one innocent stranger can't be redirected towards five. This seems paradoxical: the compound action would be permissible, but you'd be obligated to stop half way through. If redirecting the trolley is the right thing to do, we can block the paradox by saying that it's wrong to flip it there and back, because it is your duty to flip it there.

2. Undoing. If you can undo a wrong action, getting everything back to the status quo ante, you probably should. So if it's wrong to flip the lever, then if you've flipped the lever, you probably should flip it back, to undo the action. But flipping it back is uncontroversially wrong. So, probably, flipping the lever isn't wrong.

3. Advice and prevention. Typically, it's permissible to dissuade people who are resolved on a wrong action. But if someone is set on flipping the lever, it's wrong to dissuade her. For once she is resolved on flipping the lever, it is the one person on the side-track who is set to die, and so dissuading the person from flipping the lever redirects death onto the five again. But it's clearly wrong to redirect death onto the five. So, probably, flipping the lever isn't wrong. Similarly, typically one should prevent wrongdoing. But to prevent the flipping of the lever is to redirect the danger onto the five, and that's wrong.

4. Advice and prevention (reversed). The trolley is speeding towards the side-track with one person, and you see someone about to redirect the trolley onto the main track with five persons. Clearly you should try to talk the person out of it. But talking her out of it redirects death from the five innocents to the one. Hence it's right to engage in such redirection. Similarly, it's clear that if you can physical prevent the person from redirecting the trolley onto the main track, you should. But that's redirection of danger from five to one.

Trolleys, breathing, killing and letting die

Start with the standard trolley scenario: trolley is heading towards five innocent people but you can redirect it towards one. Suppose you think that it is wrong to redirect. Now add to the case the following: You're restrained in the control booth, and the button that redirects the trolley is very sensitive, so if you breathe a single breath over the next 20 seconds, the trolley will be redirected towards the one person.

To breathe or not to breathe, that is the question. If you breathe, you redirect. Suppose you hold your breath, thinking that redirecting is wrong. Why are you holding your breath, then? To keep the trolley away from the one person. But by holding your breath, you're also keeping the trolley on course towards the five. If in the original case it was wrong to redirect the trolley towards the one, why isn't it wrong to hold your breath so as to keep the trolley on course towards the five? So perhaps you need to breathe. But if you breathe, your breathing redirects the trolley, and you thought that was wrong.

I suppose the intuition behind not redirecting in the original case is a killing vs. letting die intuition: By redirecting, you kill the one. By not redirecting, you let the five die, but you don't kill them. However, when the redirection is controlled by the wonky button, things perhaps change. For perhaps holding one's breath is a positive action, and not just a refraining. So in the wonky button version, holding one's breath is killing, while breathing is letting die. So perhaps the person who thinks it's wrong to redirect in the original case can consistently say that in the breath case, it's obligatory to breathe and redirect.

But things aren't so simple. It's true that normally breathing is automatic, and that it is the holding of one's breath rather than the breathing that is a positive action. But if lives hung on it, you'd no doubt become extremely conscious of your breathing. So conscious, I suspect, that every breath would be a positive decision. So to breathe would then be a positive action. And so if redirecting in the original case is wrong, it's wrong to breathe in this case. Yet holding one's breath is generally a decision, too, a positive action. So now it's looking like in the breath-activated case, whatever happens, you do a positive action, and so you kill in both cases. It's better to kill one rather than killing five, so you should breathe.

But this approach makes what is right and wrong depend too much on your habits. Suppose that you have been trained for rescue operations by a utilitarian organization, so that it became second nature to you to redirect trolleys towards the smaller number of people. But now you've come to realize that utilitarianism is false, and you haven't been convinced by the Double Effect arguments for redirecting trolleys. Still, your instincts remain. You see the trolley, and you have an instinct to redirect. You would have to stop yourself from it. But stopping yourself is a positive action, just as holding your breath is. So by stopping yourself, you'd be killing the five. And by letting yourself go, you'd be killing the one. So by the above reasoning, you should let yourself go. Yet, surely, whether you should redirect or not doesn't depend on which action is more ingrained in you.

Where is this heading? Well, I think it's a roundabout reductio ad absurdum of the idea that you shouldn't redirect. The view that you should redirect is much more stable until such tweaks. If, on the other hand, you say in the original case that you should redirect, then you can say the same thing about all the other cases.

I think the above line of thought should make one suspicious of other cases where people want to employ the distinction between killing and letting-die. (Perhaps instead one should employ Double Effect or the distinction between ordinary and extraordinary means of sustenance.)

Pacifism and trolleys

In the standard trolley case, a runaway trolley is heading towards five innocent people, but can be redirected onto a side-track where there is only one innocent person. I will suppose that the redirection is permissible. This is hard to deny. If redirection here is impermissible, it's impermissible to mass-manufacture vaccines, since mass vaccinations redirect death from a larger number of potentially sick people to a handful of people who die of vaccine-related complications. But vaccinations are good, so redirection is permissible.

I will now suggest that it is difficult to be a pacifist if one agrees with what I just said.

Imagine a variant where the one person on the side-track isn't innocent at all. Indeed, she is the person who set the trolley in motion against the five innocents, and now she's sitting on the side-track, hoping that you'll be unwilling to get your hands dirty by redirecting the trolley at her. Surely the fact that she's a malefactor doesn't make it wrong to direct the trolley at the side-track she's on. So it is permissible to protect innocents by activity that is lethal to malefactors.

This conclusion should make a pacifist already a bit uncomfortable, but perhaps a pacifist can say that it is wrong to protect innocents by violence that is lethal to malefactors. I don't think this can be sustained. For protecting innocents by non-lethal violence is surely permissible. It would be absurd to say a woman can't pepper-spray a rapist. But now modify the trolley case a little more. The malefactor is holding a remote control for the track switch, and will not give it to you unless you violently extract it from her grasp. You also realize that when you violently extract the remote control from the malefactor, in the process of extracting it the button that switches the tracks will be pressed. Thus your violent extraction of the remote will redirect the trolley at the malefactor. Yet surely if it is permissible to do violence to the malefactor and it is permissible to redirect the trolley, it is permissible to redirect the trolley by violence done to the malefactor. But if you do that, you will do a violent action that is lethal to the malefactor.

So it is permissible to protect innocents by violence that is lethal to malefactors. Now, perhaps, it is contended that in the last trolley case, the death of the malefactor is incidental to the violence. But the same is true when one justifies lethal violence in self-defense by means of the Principle of Double Effect. For instance, one can hit an attacker with a club intending to stop the malefactor, with the malefactor's death being an unintended side-effect.

This means that if it is permissible to redirect the trolley, some lethal violence is permissible. What is left untouched, however, by this argument is a pacifism that says that it is always impermissible to intend a malefactor's death. I disagree with that pacifism, too, but this argument doesn't affect it.

Double Effect

In case anybody's thought that the trolley problem is made-up, here it is, for real, with even higher stakes.