Now suppose that thereâs only you, and youâre about to flip a coin to decide if youâll go to study bednets or deworming. Youâd prefer to commit to not then switching to the other thing.
Maybe? Iâm not sure Iâd want to constrain my future self this way, if it wonât seem best/ârational later. I donât very strongly object to commitments in principle, and it seems like the right thing to do in some cases, like Parfitâs hitchhiker. However, those assume the same preferences/âscale after, and in the two envelopes problem, we may not be able to assume that. It could look more like preference change.
In this case, it looks like youâre committing to something you will predictably later regret either way it goes (because youâll want to switch), which seems kind of irrational. It looks like violating the sure-thing principle. Plus, either way it goes, it looks like youâll fail to follow your own preferences later, and it will seem irrational then. Russell and Isaacs (2021) and Gustafsson (2022) also argue similarly against resolute choice strategies.
Iâm more sympathetic to acausal trade with other beings that could simultaneously exist with you (even if you donât know ahead of time whether youâll find bednets or deworming better in expectation), if and because youâll expect the world to be better off for it at every step: ahead of time, just before you follow through and after you follow through. Thereâs no expected regret. In an infinite multiverse (or a non-negligible chance of one), we should expect such counterparts to exist, though, so plausibly should do the acausal trade.
Also, I think youâd want to commit ahead of time to a more flexible policy for switching that depends on the specific evidence youâll gather.[1]
Now if you only think about it later, having studied bednets, Iâm imagining that you think âwell I would have wanted to commit earlier, but now that I know about how good bednets are I think deworming is better in expectation, so Iâm glad I didnât commitâ. Is that right? (I prefer to act as though Iâd made the commitment I predictably would have wanted to make.)
Ya, that seems mostly right on first intuition.
However, acausal trade with counterparts in a multiverse still seems kind of compelling.
Also, I see some other appeal in favour of committing ahead of time to stick with whatever you study (and generally making the commitment earlier, too, contra what I say above in this comment): you know thereâs evidence you could have gathered that would tell you not to switch, because you know you would have changed your mind if you did, even if you wonât gather it anymore. Your knowledge of the existence of this evidence is evidence that supports not switching, even if you donât know the specifics. It seems like you shouldnât ignore that. Maybe it doesnât go all the way to support committing to sticking with your current expertise, because you can favour the more specific evidence you actually have, but maybe you should update hard enough on it?
This seems like it could avoid both the ex ante and ex post regret so far. But, still you either:
canât be an EU maximizer, and so youâll be vulnerable to money pump arguments anyway or abandon completeness and often be silent on what to do (e.g. multi-utility representations), or
have to unjustifiably fix a single scale and prior over it ahead of time.
The same could apply to humans vs aliens. Even if weâre not behind the veil of ignorance now and never were, thereâs information that weâd be ignoring: what real or hypothetical aliens would believe and the real or hypothetical existence of evidence that supports their stance.
But, itâs also really weird to consider the stances of hypothetical aliens. Itâs also weird in a different way if you imagine finding out what itâs like to be a chicken and suffer like a chicken.
Suppose youâre justifiably sure that each intervention is at least not net negative (whether or not you have a single scale and prior). But then you find out bednets have no (or tiny) impact. I think it would be reasonable to switch to deworming at some cost. Deworming could be less effective than you thought ahead of time, but no impact is as bad as it gets given your credences ahead of time.
Maybe? Iâm not sure Iâd want to constrain my future self this way, if it wonât seem best/ârational later. I donât very strongly object to commitments in principle, and it seems like the right thing to do in some cases, like Parfitâs hitchhiker. However, those assume the same preferences/âscale after, and in the two envelopes problem, we may not be able to assume that. It could look more like preference change.
In this case, it looks like youâre committing to something you will predictably later regret either way it goes (because youâll want to switch), which seems kind of irrational. It looks like violating the sure-thing principle. Plus, either way it goes, it looks like youâll fail to follow your own preferences later, and it will seem irrational then. Russell and Isaacs (2021) and Gustafsson (2022) also argue similarly against resolute choice strategies.
Iâm more sympathetic to acausal trade with other beings that could simultaneously exist with you (even if you donât know ahead of time whether youâll find bednets or deworming better in expectation), if and because youâll expect the world to be better off for it at every step: ahead of time, just before you follow through and after you follow through. Thereâs no expected regret. In an infinite multiverse (or a non-negligible chance of one), we should expect such counterparts to exist, though, so plausibly should do the acausal trade.
Also, I think youâd want to commit ahead of time to a more flexible policy for switching that depends on the specific evidence youâll gather.[1]
Ya, that seems mostly right on first intuition.
However, acausal trade with counterparts in a multiverse still seems kind of compelling.
Also, I see some other appeal in favour of committing ahead of time to stick with whatever you study (and generally making the commitment earlier, too, contra what I say above in this comment): you know thereâs evidence you could have gathered that would tell you not to switch, because you know you would have changed your mind if you did, even if you wonât gather it anymore. Your knowledge of the existence of this evidence is evidence that supports not switching, even if you donât know the specifics. It seems like you shouldnât ignore that. Maybe it doesnât go all the way to support committing to sticking with your current expertise, because you can favour the more specific evidence you actually have, but maybe you should update hard enough on it?
This seems like it could avoid both the ex ante and ex post regret so far. But, still you either:
canât be an EU maximizer, and so youâll be vulnerable to money pump arguments anyway or abandon completeness and often be silent on what to do (e.g. multi-utility representations), or
have to unjustifiably fix a single scale and prior over it ahead of time.
The same could apply to humans vs aliens. Even if weâre not behind the veil of ignorance now and never were, thereâs information that weâd be ignoring: what real or hypothetical aliens would believe and the real or hypothetical existence of evidence that supports their stance.
But, itâs also really weird to consider the stances of hypothetical aliens. Itâs also weird in a different way if you imagine finding out what itâs like to be a chicken and suffer like a chicken.
Suppose youâre justifiably sure that each intervention is at least not net negative (whether or not you have a single scale and prior). But then you find out bednets have no (or tiny) impact. I think it would be reasonable to switch to deworming at some cost. Deworming could be less effective than you thought ahead of time, but no impact is as bad as it gets given your credences ahead of time.