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by jjk166 981 days ago
The problem here stems from trying to have some universal utility values for acts. You can't say cutting off a finger is fundamentally worse than losing 10 pounds, even if it frequently would be. I wouldn't give up one of my fingers for 10 pounds, and I think most sane people wouldn't either, but here the mugger is willing to do that. So in this particular instance, the mugger is valuing the utility of keeping his finger at 10 pounds, and thus the decision on whether or not to give it to him is a wash. The moment you start dictating what the utility values are of consequences for other people you get absurd outcomes (e.g. some of you may die, but it's a sacrifice I'm willing to make).
1 comments
hgomersall 980 days ago
He's not, he's explicitly saying the value to him of his finger is more than £10. The finger is clearly a case where the utility disparity is obvious.
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jjk166 980 days ago
He can say it's worth whatever he wants, but the fact is he is willing to cut off his finger in an effort to get £10, thus £10 must provide equal or greater utility.

> The finger is clearly a case where the utility disparity is obvious.

This is the erroneous assumption that leads to the false conclusion. There's no such thing as an obvious utility disparity. It's a decent heuristic that works fine in the real world, but in this imaginary scenario where a person would actually be willing to cut off their own fingers simply because they have not gained £10, it no longer holds true.

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hgomersall 980 days ago
He's not willing to do it. He explicitly does not want to do it and is only going to do it to lower overall utility by more than the £10 can provide to either party. That is, it only makes sense if he values his finger by more than £10.
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jjk166 980 days ago
We're dealing with two different definitions of "willing." You're using willing to mean a desire to do it. I'm using willing to mean he will choose to do it. It's like I desire to quit my job, but I don't actually quit, because I'm not willing. I desire to be fit, but I'm not willing to give up desert.

It doesn't matter how much the mugger claims he doesn't want to lose his fingers, the fact that he will nevertheless choose a path that causes him to lose his fingers of his own volition means that he has set the utility as being lower.

Yes, the premise only makes sense if he values his finger more than £10, but he demonstrably does not, ergo the premise is contradicted.

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