Well, yes. Any sane choice of UTM is famously pretty equivalent in terms of epistemology, if you’re willing to presume that sanity. Eg, to end up thus convinced against all evidence that Guam is planning to invade the United States, you’d have to twist up the UTM to make it hugely costly to internally simulate other UTMs that would assign greater than negligible probability to “Guam is not planning to invade the United States”. And even then, it washes out in the limit, etcetera.
But if we suppose it to be a prior metaphysical fact out there in the territory, you’d think the territory actually would have to fix some choice of UTM; the territory cannot just say, “Eh, they’re pretty much equivalent” and leave itself uncertain, for all uncertainty exists in the map rather than the territory.
If the territory has picked any sane UTM, all sane UTMs will do well pretty well predicting it.
But how would the territory pick any UTM whatsoever to decide which universes got exactly how much reality-fluid?
I dunno. Maybe the mathematical realists would say that this is one of the very few things that actually are nailed down to one particular option in the laws of metaphysical reality, rather than all the mathematically self-consistent options getting a little bit of reality fluid?
It seems sort of counter to the ethos of the whole endeavour as I understand it, but I don’t really see any other way for them to do it. It seems to me like you’ve got to make some statements of the form “metareality is like this thing, not like this other thing” at some point, if you want to make meaningful statements about some sort of metareality at all. And any statement like that will presumably end up being expressible mathematically.
Well, yes. Any sane choice of UTM is famously pretty equivalent in terms of epistemology, if you’re willing to presume that sanity. Eg, to end up thus convinced against all evidence that Guam is planning to invade the United States, you’d have to twist up the UTM to make it hugely costly to internally simulate other UTMs that would assign greater than negligible probability to “Guam is not planning to invade the United States”. And even then, it washes out in the limit, etcetera.
But if we suppose it to be a prior metaphysical fact out there in the territory, you’d think the territory actually would have to fix some choice of UTM; the territory cannot just say, “Eh, they’re pretty much equivalent” and leave itself uncertain, for all uncertainty exists in the map rather than the territory.
If the territory has picked any sane UTM, all sane UTMs will do well pretty well predicting it.
But how would the territory pick any UTM whatsoever to decide which universes got exactly how much reality-fluid?
I dunno. Maybe the mathematical realists would say that this is one of the very few things that actually are nailed down to one particular option in the laws of metaphysical reality, rather than all the mathematically self-consistent options getting a little bit of reality fluid?
It seems sort of counter to the ethos of the whole endeavour as I understand it, but I don’t really see any other way for them to do it. It seems to me like you’ve got to make some statements of the form “metareality is like this thing, not like this other thing” at some point, if you want to make meaningful statements about some sort of metareality at all. And any statement like that will presumably end up being expressible mathematically.