I really enjoyed this post, but have a few issues that make me less concerned about the problem than the conclusion would suggest:
- Your dismissal in section X of the “weight by simplicity” approach seems weak/wrong to me. You treat it as a point against such an approach that one would pay to “rearrange” people from more complex to simpler worlds, but that seems fine actually, since in that frame it’s moving people from less likely/common worlds to more likely/common ones.
- I lean towards conceptions of what makes a morally relevant agent (or experience) under which there are only countably many of them. It seems like two people with the exact same full life experience history are the same person, and the same seems plausible for two people whose full-life-experience-histories can’t be distinguished by any finite process, in which case each person can be specified by finitely much information and so there are at most countably many of them. I think if you’re willing to put 100% credence on some pretty plausible physics you can maybe even get down to finitely many possible morally relevant morally distinct people, since entropy and the speed of light may bound how large a person can be.
- My actual current preferred ethics is essentially “what would I prefer if I were going to be assigned at random to one of the morally-relevant lives ever eventually lived” (biting the resulting “sadistic conclusion”-flavoured bullets). For infinite populations this requires that I have some measure on the population, and if I have to choose the measure arbitrarily then I’m subject to most of the criticisms in this post. However I believe the infinite cosmology hypotheses referenced generally come along with fundamental measures? Indeed a measure over all the people one might be seems like it might be necessary for a hypothesis that purports to describe the universe in which we in fact find ourselves. If I have to dismiss hypotheticals that don’t provide me with a measure on the population as ill-formed and assign zero credence to universes without a fundamental measure that’s a point against my approach but I think not a fatal one.
I really enjoyed this post, but have a few issues that make me less concerned about the problem than the conclusion would suggest:
- Your dismissal in section X of the “weight by simplicity” approach seems weak/wrong to me. You treat it as a point against such an approach that one would pay to “rearrange” people from more complex to simpler worlds, but that seems fine actually, since in that frame it’s moving people from less likely/common worlds to more likely/common ones.
- I lean towards conceptions of what makes a morally relevant agent (or experience) under which there are only countably many of them. It seems like two people with the exact same full life experience history are the same person, and the same seems plausible for two people whose full-life-experience-histories can’t be distinguished by any finite process, in which case each person can be specified by finitely much information and so there are at most countably many of them. I think if you’re willing to put 100% credence on some pretty plausible physics you can maybe even get down to finitely many possible morally relevant morally distinct people, since entropy and the speed of light may bound how large a person can be.
- My actual current preferred ethics is essentially “what would I prefer if I were going to be assigned at random to one of the morally-relevant lives ever eventually lived” (biting the resulting “sadistic conclusion”-flavoured bullets). For infinite populations this requires that I have some measure on the population, and if I have to choose the measure arbitrarily then I’m subject to most of the criticisms in this post. However I believe the infinite cosmology hypotheses referenced generally come along with fundamental measures? Indeed a measure over all the people one might be seems like it might be necessary for a hypothesis that purports to describe the universe in which we in fact find ourselves. If I have to dismiss hypotheticals that don’t provide me with a measure on the population as ill-formed and assign zero credence to universes without a fundamental measure that’s a point against my approach but I think not a fatal one.