You and me live in the open desert, and our dear mother is trapped there (assume some mythology). She’ll die unless we stay and shade her. We want her to survive, but we want to live our lives as well. You plan to leave for Olympos, where you’ll have a really fun time, and will send some remittances and nymphs.
But instead, I leave before you do, safe in the knowledge that you will feel forced to stay behind and shade mother. So mother gets taken care of, and I get to enjoy the Olympos (and I won’t bother sending anything). Blackmail?
What if the problem were entirely symmetric, and we both had exactly the same preferences. One of us has to stay, one has to go. Is it blackmail if I go first, and thus force you to stay?
Note that if you were literally a rock, I’d leave joyfully, as you’d be shading mother with no problem. I’m “blackmailing” you to inaction, not to action (which shouldn’t really make a difference).
You and me live in the open desert, and our dear mother is trapped there (assume some mythology).
No mythology necessary, actually. Two daughters and an aging mother. Which of the two gets to marry and move away from home, and which is left behind? My mother, her sister, and their mother. All dead now, so I can’t ask any of them if there was any conflict over it.
This is not something I would call blackmail, any more than I would call theft blackmail. Fait accompli: one of the two simply does something to the disadvantage of the other. It may of course be morally wrong, but there are many varieties of wrong, only some of which are blackmail.
But this is just a terminological question. The real question here is presumably: how can a rational agent be designed not to be exploitable by fait accompli?
What if the problem were entirely symmetric, and we both had exactly the same preferences. One of us has to stay, one has to go. Is it blackmail if I go first, and thus force you to stay?
Well, If I have a chance to react to that before your decision is final, I could say that if you do that then I’ll go anyway (Thus leaving mother to burn) Then it seems to resolve to Chicken. (We both want the other person to back down first, so that we can go all the way to Olympos, but if neither backs down, mother burns in desert heat.)
And if I don’t have a chance to react to that before your decision is final, then it’s sort of like “What do you do if you are playing Chicken against someone who has already smashed his steering column with a rock?”
And I think that makes sense, since in both cases (blackmail, chicken) the goal is make the person back down because of some sort of threat. Does that help?
As I said elsewhere, I think identifying blackmail depends on identifying an agreed status quo state. This is fairly easy in ordinary life (if we had an affair, the ordinary human expectation is that you would keep the letters secret for free, etc.), but more difficult in outré cases like this one and the other one you suggest with the letters in the cave. It is not surprising therefore that in cases like this we do not have clear intuitions.
That said, following the definition I proposed, I’d say that in your first example if it is a plausible status quo that your brother would go to Olympos (maybe he got a job offer letter form there?) then it is blackmail for you to go instead. If he just happened to come up with the idea of leaving, then my intuition is that this is not a plausible status quo; there is no stability, no ordinary human expectation that you would abide by his decision of leaving you stranded. A more plausible status quo (which applies also to the perfectly symmetric case when both come up with the idea together) would be flipping a coin to decide who leaves. Relative to this, either of you leaving is blackmailing the other.
Blackmail with literal rocks!
You and me live in the open desert, and our dear mother is trapped there (assume some mythology). She’ll die unless we stay and shade her. We want her to survive, but we want to live our lives as well. You plan to leave for Olympos, where you’ll have a really fun time, and will send some remittances and nymphs.
But instead, I leave before you do, safe in the knowledge that you will feel forced to stay behind and shade mother. So mother gets taken care of, and I get to enjoy the Olympos (and I won’t bother sending anything). Blackmail?
What if the problem were entirely symmetric, and we both had exactly the same preferences. One of us has to stay, one has to go. Is it blackmail if I go first, and thus force you to stay?
Note that if you were literally a rock, I’d leave joyfully, as you’d be shading mother with no problem. I’m “blackmailing” you to inaction, not to action (which shouldn’t really make a difference).
No mythology necessary, actually. Two daughters and an aging mother. Which of the two gets to marry and move away from home, and which is left behind? My mother, her sister, and their mother. All dead now, so I can’t ask any of them if there was any conflict over it.
This is not something I would call blackmail, any more than I would call theft blackmail. Fait accompli: one of the two simply does something to the disadvantage of the other. It may of course be morally wrong, but there are many varieties of wrong, only some of which are blackmail.
But this is just a terminological question. The real question here is presumably: how can a rational agent be designed not to be exploitable by fait accompli?
I did the mythology simply so I could make one of them into a literal rock at the end :-)
It still has some similarities—in that they would only move away because of the expected behaviour of the other...
Well, If I have a chance to react to that before your decision is final, I could say that if you do that then I’ll go anyway (Thus leaving mother to burn) Then it seems to resolve to Chicken. (We both want the other person to back down first, so that we can go all the way to Olympos, but if neither backs down, mother burns in desert heat.)
And if I don’t have a chance to react to that before your decision is final, then it’s sort of like “What do you do if you are playing Chicken against someone who has already smashed his steering column with a rock?”
And I think that makes sense, since in both cases (blackmail, chicken) the goal is make the person back down because of some sort of threat. Does that help?
As I said elsewhere, I think identifying blackmail depends on identifying an agreed status quo state. This is fairly easy in ordinary life (if we had an affair, the ordinary human expectation is that you would keep the letters secret for free, etc.), but more difficult in outré cases like this one and the other one you suggest with the letters in the cave. It is not surprising therefore that in cases like this we do not have clear intuitions.
That said, following the definition I proposed, I’d say that in your first example if it is a plausible status quo that your brother would go to Olympos (maybe he got a job offer letter form there?) then it is blackmail for you to go instead. If he just happened to come up with the idea of leaving, then my intuition is that this is not a plausible status quo; there is no stability, no ordinary human expectation that you would abide by his decision of leaving you stranded. A more plausible status quo (which applies also to the perfectly symmetric case when both come up with the idea together) would be flipping a coin to decide who leaves. Relative to this, either of you leaving is blackmailing the other.