This is a messy reply but I already rewrote it 2.5 times, haha.
I do think there’s a, not quite conflation, but a meaningful social and practical distinction to be made between “universal metaphysics” and “identity metaphysics”. The former requires stronger arguments, but the latter is generally much weaker. I don’t believe FDT requires the former, but that it serves as good intuition pumps. For the latter, I think there’s more legitimate ground to dispute there, but I still think many disputes are confusions. Such as “I believe in free will, so I don’t believe in perfect predictors”, wherein the confusion is presuming we need perfect predictors to justify FDT, and that all you need there is some decent amount of prediction of decisions which is much weaker and much more commonly believed to be possible even if perhaps not physically feasible. Similarly, FDT is much easier to conceptualize with more computationalist theory of identity/mind, but is mostly not required; yet it does lead to pushback due to considering algorithms more primitively.
I also think I disagree with your son of CDT. In justification for FDT, sure everyday commitments aren’t necessarily FDT, but are often used in terms of “we use predictions of other people’s actions to decide what actions to take” which is very much in spirit of FDT and closer than how people conceptualize CDT or commitments. Though there’s of course some problems that feel more natural in either, and some in neither even if related (ex: virtues). But I don’t think this is central beyond pushing people away from typical naive CDT.
I generally avoided Bentham’s posts because I’ve seen him argue against FDT some years ago and on X he doesn’t seem to have gotten substantially better so it never felt worthwhile (though I guess I got convinced to argue against his recent post on SSA implying theism...)
But, looking at the top comments, it is pretty direct. Mark saying “It is fine to give the wrong answer in a probabilistic sense” which is explicitly about the mechanics and justification for FDT. Vaniver is talking about concrete justifications for/against concrete payoffs. Etc. I don’t think this is dominantly semantics. Sure, it isn’t metaphysics, but generally it isn’t believed metaphysics is the problem. I think you’re over interpreting by your issue with lack of metaphysics to think most of it is missing the point.
Separately, the definition of “rationality” does matter. If you defined rationality as CDT-rational (as is often implicit in decision theory texts) then FDT will be worse by that definition.
If you’re just saying “use rationality for near-term naive optimal decision making” as you do in your commitment theory post, then we can do that, but I also think it is an active distortion of what humans mean by rational in order to waffle between “well, it doesn’t matter, we’re just making ourselves be irrational to get more utility”. That is, why add more epicycles with commitment theory over decision theory? Why not just be exact with what is being constructed? Collapse these layers and extract The Right Answer, and then move on to studying bounded agents, embedded agents, etc. to make our understanding of the nature of decisions ever more complete.
(That is, the semantics matter because words mean something, and also because they matter to interlocutors, if they consider that a relevant “resolution” of the problem at hand rather than a minor fiddly bit to ignore)
This is a messy reply but I already rewrote it 2.5 times, haha. I do think there’s a, not quite conflation, but a meaningful social and practical distinction to be made between “universal metaphysics” and “identity metaphysics”. The former requires stronger arguments, but the latter is generally much weaker. I don’t believe FDT requires the former, but that it serves as good intuition pumps. For the latter, I think there’s more legitimate ground to dispute there, but I still think many disputes are confusions. Such as “I believe in free will, so I don’t believe in perfect predictors”, wherein the confusion is presuming we need perfect predictors to justify FDT, and that all you need there is some decent amount of prediction of decisions which is much weaker and much more commonly believed to be possible even if perhaps not physically feasible. Similarly, FDT is much easier to conceptualize with more computationalist theory of identity/mind, but is mostly not required; yet it does lead to pushback due to considering algorithms more primitively.
I also think I disagree with your son of CDT. In justification for FDT, sure everyday commitments aren’t necessarily FDT, but are often used in terms of “we use predictions of other people’s actions to decide what actions to take” which is very much in spirit of FDT and closer than how people conceptualize CDT or commitments. Though there’s of course some problems that feel more natural in either, and some in neither even if related (ex: virtues). But I don’t think this is central beyond pushing people away from typical naive CDT.
I generally avoided Bentham’s posts because I’ve seen him argue against FDT some years ago and on X he doesn’t seem to have gotten substantially better so it never felt worthwhile (though I guess I got convinced to argue against his recent post on SSA implying theism...) But, looking at the top comments, it is pretty direct. Mark saying “It is fine to give the wrong answer in a probabilistic sense” which is explicitly about the mechanics and justification for FDT. Vaniver is talking about concrete justifications for/against concrete payoffs. Etc. I don’t think this is dominantly semantics. Sure, it isn’t metaphysics, but generally it isn’t believed metaphysics is the problem. I think you’re over interpreting by your issue with lack of metaphysics to think most of it is missing the point.
Separately, the definition of “rationality” does matter. If you defined rationality as CDT-rational (as is often implicit in decision theory texts) then FDT will be worse by that definition. If you’re just saying “use rationality for near-term naive optimal decision making” as you do in your commitment theory post, then we can do that, but I also think it is an active distortion of what humans mean by rational in order to waffle between “well, it doesn’t matter, we’re just making ourselves be irrational to get more utility”. That is, why add more epicycles with commitment theory over decision theory? Why not just be exact with what is being constructed? Collapse these layers and extract The Right Answer, and then move on to studying bounded agents, embedded agents, etc. to make our understanding of the nature of decisions ever more complete. (That is, the semantics matter because words mean something, and also because they matter to interlocutors, if they consider that a relevant “resolution” of the problem at hand rather than a minor fiddly bit to ignore)