Wednesday, January 3, 2018

Badness and deontological prohibitions

The following form of argument has some initial plausibility:

  1. Ordinarily, action type A is no better than action type B.

  2. So, if there is no deontological prohibition against A, there is no deontological prohibition against B.

But here’s an interesting fact. One can have pairs of action types A and B such that:

  1. under ordinary circumstances, A is worse than B, but

  2. there is a deontological prohibition against B but not against A.

For instance, let A be a train engineer’s choosing not to brake a slow moving train ahead of a section of track on which there are ten innocents tied up. Let B be the train engineer’s shooting one innocent dead (knowingly, without divine permission, etc.).

Under ordinary circumstances, A is worse than B. But if Alice reliably informs the train engineer that she will murder fifty people if the engineer brakes, the engineer is permitted (and probably obligated) to refrain from braking. Hence there is no deontological prohibition against A. But if Alice informs the train engineer that she will murder fifty people if the engineer refuses to shoot the innocent, the engineer must still still refuse. There is a deontological prohibition against B.

So, while there is some correlation between ordinary worseness and deontological prohibition, that correlation has exceptions.


Martin Cooke said...

I think that A is ordinarily better than B, in your specific example, precisely because there is that law against B (maybe also for other reasons that might be connected to that reason, e.g. whoever tied the ten up would probably want to kill them another way if the train braked). You may well be right on some readings of "better" though.

Walter Van den Acker said...

I really don't see why there is a deontological prohibition against B but not against A. "Refraining from braking" when there are innocent people on the track is decison by the engineer to kill ten people, that may be mitigated by the fact that he did it in order to save 50 people. Likewise, the engineers decision to shoot th innocent, may be mitigated by his desire to save the fifty others.
Let's suppose Alice gives the engineer the choice: here is John, an innocent guy and ahead of you are ten other innocent people on the track. Now, either you shoot John or I will kill 50 people, or you refrain from braking, in which case, the 50 innocent people, as well as John stay alive.
What should the engineer do? According to your deontology, he should still opt for A, but what, might I ask, is this deontology based on?

Alexander R Pruss said...


Normally we do not have an obligation to save lives when saving the lives costs more lives than it saves, and when the numbers are disproportionate, we have an obligation to refrain from saving the lives at that cost. If ten people are trapped in a cave, and the only way to rescue them is to blow up the blockage at the entrance, which however will cause an avalanche that will kill fifty people in the village below, it is normally wrong to blow up the blockage. When Alice informs the engineer in my story that she will kill fifty if he brakes, then his saving the lives of the people on the track costs more lives than it saves.

On the other hand, we do have an obligation to refrain from killing innocents even when we could save more lives by doing so.

In your case, the engineer has these choices:
1. Do nothing.
2. Shoot John.
3. Shoot John and brake.
4. Brake and not shoot John.

Options 2 and 3 include the murder of John, and so are wrong.
Options 4 saves 10 people at the cost of 50, and one shouldn't save lives at such a high cost.
That leave Option 1 as the only permissible option.

Maybe your intuitions are due to a feeling that an engineer's braking is a little different from saving lives. We don't usually say that when a driver stops at a cross-walk to avoid running into people that she has saved lives. Stopping for pedestrians is normal driving practice. On the other hand, if you saw a driverless car heading for a group of pedestrians and jumped into the car and hit the brakes, we would say that you saved lives. I think this has to do with background expectations ( see ): drivers routinely brake for pedestrians, but people don't routinely jump into cars to brake.

However, in special circumstances the background expectations change. Suppose that an engineer was told that if she brakes before the innocents, she (and only she) will be killed. And she brakes. In that case, we would say that she saved innocent lives at the cost of her own. This is because in those special circumstances, what is normally a routine act of braking becomes a heroic act. Likewise, in the special circumstances where 50 will be killed if she brakes, her braking would no longer be a routine act--it would be an act of saving 10 lives at too high a cost.

Martin Cooke said...

On the other hand, if the driver had earlier tied those ten to the tracks, how then would his decision to kill them by not braking be so fundamentally different to a decision to kill them by shooting them?

Alexander R Pruss said...

Imagine, though, that the driver who tied the ten to the tracks repented of the deed. However, now an associate tells him that if he brakes, fifty will be killed. Should he brake? I don't think so.

Martin Cooke said...

And yet I do think so, reasoning thus: he is responsible for those ten being there, and so this is indeed a lot like shooting ten people. But I also think that even if someone else had tied them up, he should brake, reasoning thus: he only has hearsay on those fifty, and hearsay from a maniac at that, whereas he can see the ten in front of his eyes.

btw ... might one chop up the shooting of an innocent (outside of a just war etc.) into actions that are individually permissible and collectively exhaust the shooting? What would that mean?

Martin Cooke said...

I could have got the wrong end of the stick, of course.

Usually, tying the ten to the tracks will be murder. But if they do not die then it is not murder. So he should brake so that he is not a murderer.

Alternatively, it is not murder, and then I wonder about the shooting: is that not the doing of lots of permissible actions?

Walter Van den Acker said...

Dr Pruss

But why is "the murder of John" not permissible?
You keep saying that there is a deotological prohibition against murdering someone, but what is the basis for that prohibition? After all, if the train driver doesn't brake, he kills ten people. How is that nor murder?
Suppose he wanted to get rid of his wife and one day sees her lying unconscious on the track.
Wouldn't you say that if he doesn't brake, he will be conisdered a murderer?

The only difference I see between the two scenarios is his motive. In one case he wants his wife's death, in the other case he wants to save the lives of 50 people.
But that's exactly the same in the case of shooting John. His motive would be to save lives.

So, there seems to be something arbitrary in the deontologic prohibition.

Alexander R Pruss said...

There are two relevant differences: (a) commission vs. omission, and (b) intention. The second is probably the more important one. If he shoots John, he intends to to shoot John, even if it's only a means to a further (and good end). If he doesn't brake, however, he isn't intending to run over the innocents, even as a means. He is intending simply not to brake.

Walter Van den Acker said...

That's a difference, all right, but I don't agree that he's simply intending not to brake. He is, from the moment he knows that there are people on the track, by his decision not to brake, intending to run over the innocents.

Lets forget about motives for a moment. If he decides to shoot a guy,his intent is to shoot the guy, that's clear. Now suppose he sees a guy on the track, never mind how he gets there, and decides not to brake even though he has plenty of time to reflect on it, then according to you he doesn't intend to run over this guy?

I really don't see the relevance of this diffence. And neither will any judge, I am afraid.

Angra Mainyu said...


I think that shooting the innocent is permissible (or even obligatory) under certain circumstances, like (for at least permissibility):

1. A powerful alien threatens to torture that innocent horribly for 1000 years (I can come up with a graphic account if needed), and then also very painfully killing him. The innocent is unconscious. The person told to shoot him reckons and should reckon that if he fails to shoot him, the alien will in fact carry out the threat. Then, shooting is permissible.

2. Like 1., but the innocent is conscious, and begs to be shot dead, to avoid a far worse fate.

Granted, you disagree that it's permissible to kill under those circumstances as well, or any other circumstances, no matter what. But I find this highly counterintuitive (also, apart from my own moral sense, I think a claim like this would very probably look clearly false to most people, especially when one can make the horrific torture last longer, describe it vividly, etc.).

That said, it may well always be immoral to (intend to) kill an innocent because there is a threat that otherwise, someone else will kill more innocents. But in that case, the deontological prohibition is against doing something for such-and-such reason, so we do not have B anymore, but rather, intending to kill for such-and-such reason.

Alexander R Pruss said...


Intentions help explain actions. If the belief that he will run someone over does not help explain why he is not braking, then he doesn't intend to run that person over. He may, of course, still be guilty of a grave moral failing, but not of intending to run someone over.

The law's determination of mens rea in the case of murder is oversimplified.

Walter Van den Acker said...

Dr Pruss

But that's my whole point. The belief that he will run someone over does help explain why he is not braking.

Martin Cooke said...

Logically, either Walter is right: the driver is choosing to run them over and is therefore murdering them; or else this is not murder: but then how is A ordinarily worse than B? The sum of the tying them to the tracks and the running of them over would be worse than a single murder, insofar as we can do such sums with murders, but it would be the tying them to the tracks that was the worst of it.

Martin Cooke said...

"Imagine, though, that the driver who tied the ten to the tracks repented of the deed. However, now an associate tells him that if he brakes, fifty will be killed. Should he brake? I don't think so."

Similarly, though, what if I point a gun at you and fire, but as I feel the trigger go I have a massive worry about it, and as I hear the retort I totally repent? What if that is a fleeting reaction on my part, and I proceed to dispassionately watch you bleed out, not even phoning for an ambulance? A devil might whisper in my ear, after I have shot you and repented, telling me that many souls will suffer if I offer you assistance: you think that I should not make you good?

Alexander R Pruss said...

Yeah, it seems that if the cost of calling for an ambulance is really high, you shouldn't call for the ambulance. Imagine that you know that if the ambulance comes, on the way it will run over a dozen people who are lying on the road (maybe you have a button that calls an ambulance, and you can't explain about the people on the road). Clearly you shouldn't call the ambulance.

Martin Cooke said...

I see; presumably there is still that prohibition against shooting you in the first place.
And yet, there is presumably no deontological prohibition against tying people to train tracks; and I did try to get the scenarios to be parallel (I'm probably just confusing myself though).

Alexander R Pruss said...

There is a prohibition against tying innocent people to train track *in order to kill them*, though.

Martin Cooke said...

Indeed; and I also imagine that if a demon tells me to tie someone to a track and drive a train over them or else he will kill more people, then I should not do it because I think that that would kill them, even though I would be doing it in order to save others: it is just like the prohibition against shooting some innocent even if it would save other lives. But, what if the demon tells me to tie someone to tracks, or else? That might not kill them; indeed, I may be intending to untie them, so that must be OK. The demon then tells me not to untie them, which worries me, but I am assured that this is like not applying brakes, and so is OK too. And similarly for starting and not braking the train. So in short, it seems to me that the prohibition can be evaded: I might intend to save lives by killing someone, and then carry out that action in a way that is not prohibited by using my worry about it being prohibited to adopt, at deontologically crucial stages, an open mind about whether or not I will carry it out. And that does not seem good enough?

Alexander R Pruss said...


Yeah, this is hard. I think there needs to be some principles in moral thought about cooperation with evil. The Catholic moral tradition has a basic distinction between "formal" and "material" cooperation: in formal cooperation you share the evildoer's intention; in material cooperation, you don't. Formal cooperation is always wrong. Material cooperation varies from case to case, with closer and more direct forms being more morally problematic. This seems right, but measuring closeness and directness is hard.

Normally, I think, tying someone down and leaving them on the train track would count as a very close form of cooperation with killing. But what if you planned to return before the train came, and remove them? Then it seems like it should be OK. In that case, as far as you know, you aren't even cooperating with the evil of murder, because you don't expect the evil to take place--you think you can prevent it.

But what if, when you return, the evildoer is there and tells you not to remove them or else something much worse will happen? Then it seems you've been tricked. You thought that you weren't cooperating with an evil, but you were. Your cooperation was pretty close. But it was unwitting, and hence excused. So in the case where you first planned to untie, your initial tying up could have been justified. But if at the beginning you already foresaw that the evildoer would do that, then it's wrong to cooperate with the tying up.

How close is too close? I don't know. It is clear that aiming a gun at an innocent person and pulling the trigger is too close. Giving poison to an innocent person is also too close, unless you have a reasonable hope you'll be able to give them an antidote.

Martin Cooke said...

Yes: "material cooperation" seems to hit the nail on the head; interesting ...

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