and it seems detrimental when making the last one (I don’t need to be thinking about what I drew in other universes).
UDT doesn’t ask you to think about what you drew in the other universes, because presumably the decisions you’d have made with different cards aren’t a logical consequence of the decision you make with your current cards. So you still end up maximizing the sum of utility*weight over all universes using the original non-updated weights, but the terms corresponding to the other universes happen to be constant, so you only look at the term corresponding to the current universe. UDT doesn’t add value here, but nor does it harm; it actually agrees with CDT in most non-weird situation, like your casino example. UDT is a generalization of CDT to the extreme cases where causal intuition fails—it doesn’t throw away the good parts.
Overall, it seems that my attempt at communication in the original post has failed. Oh well.
Only if it’s costless to check that your decisions in this universe don’t actually impact the other universes. UDT seems useful as a visualization technique in a few problems, but I don’t think that’s sufficient to give it a separate name (intended as speculation, not pronouncement).
Overall, it seems that my attempt at communication in the original post has failed. Oh well.
Well, it was worth a shot. I think the main confusion on my end, which I think I’ve worked through, is that UDT is designed for problems I don’t believe can exist- and so the well is pretty solidly poisoned there.
UDT is supposed to be about fundamental math, not efficient algorithms. It’s supposed to define what value we ought to optimize, in a way that hopefully accords with some of our intuitions. Before trying to build approximate computations, we ought to understand the ideal we’re trying to approximate in the first place. Real numbers as infinite binary expansions are pretty impractical for computation too, but it pays to get the definition right.
Whether UDT is useful in reality is another question entirely. I’ve had a draft post for quite a while now titled “Taking UDT Seriously”, featuring such shining examples as: it pays to retaliate against bullies even at the cost of great harm to yourself, because anticipation of such retaliation makes bullies refrain from attacking counterfactual versions of you. Of course the actual mechanism by which bullies pick victims is different and entirely causal—maybe some sort of pheromones indicating willingness to retaliate—but it’s still instructive how an intuition from the platonic math of UDT unexpectedly transfers to the real world. There may be a lesson here.
That draft would be interesting to see completed, and it may help me see what UDT brings to the table. I find the idea of helping future me and other people in my world far more compelling than the idea of helping mes that don’t exist in my world- and so if I can come to the conclusion “stand up to bullies at high personal cost because doing so benefits you and others in the medium and long term,” I don’t see a need for nonexistent mes, and if I don’t think it’s worth it on the previously stated grounds, I don’t see the consideration of nonexistent mes changing my mind.
Again, that can be a potent visualization technique, by imagining a host of situations to move away from casuistry towards principles or to increase your weighting of your future circumstances or other’s circumstances. I’m not clear on how a good visualization technique makes for an ideal, though.
UDT doesn’t ask you to think about what you drew in the other universes, because presumably the decisions you’d have made with different cards aren’t a logical consequence of the decision you make with your current cards. So you still end up maximizing the sum of utility*weight over all universes using the original non-updated weights, but the terms corresponding to the other universes happen to be constant, so you only look at the term corresponding to the current universe. UDT doesn’t add value here, but nor does it harm; it actually agrees with CDT in most non-weird situation, like your casino example. UDT is a generalization of CDT to the extreme cases where causal intuition fails—it doesn’t throw away the good parts.
Overall, it seems that my attempt at communication in the original post has failed. Oh well.
Only if it’s costless to check that your decisions in this universe don’t actually impact the other universes. UDT seems useful as a visualization technique in a few problems, but I don’t think that’s sufficient to give it a separate name (intended as speculation, not pronouncement).
Well, it was worth a shot. I think the main confusion on my end, which I think I’ve worked through, is that UDT is designed for problems I don’t believe can exist- and so the well is pretty solidly poisoned there.
UDT is supposed to be about fundamental math, not efficient algorithms. It’s supposed to define what value we ought to optimize, in a way that hopefully accords with some of our intuitions. Before trying to build approximate computations, we ought to understand the ideal we’re trying to approximate in the first place. Real numbers as infinite binary expansions are pretty impractical for computation too, but it pays to get the definition right.
Whether UDT is useful in reality is another question entirely. I’ve had a draft post for quite a while now titled “Taking UDT Seriously”, featuring such shining examples as: it pays to retaliate against bullies even at the cost of great harm to yourself, because anticipation of such retaliation makes bullies refrain from attacking counterfactual versions of you. Of course the actual mechanism by which bullies pick victims is different and entirely causal—maybe some sort of pheromones indicating willingness to retaliate—but it’s still instructive how an intuition from the platonic math of UDT unexpectedly transfers to the real world. There may be a lesson here.
That draft would be interesting to see completed, and it may help me see what UDT brings to the table. I find the idea of helping future me and other people in my world far more compelling than the idea of helping mes that don’t exist in my world- and so if I can come to the conclusion “stand up to bullies at high personal cost because doing so benefits you and others in the medium and long term,” I don’t see a need for nonexistent mes, and if I don’t think it’s worth it on the previously stated grounds, I don’t see the consideration of nonexistent mes changing my mind.
Again, that can be a potent visualization technique, by imagining a host of situations to move away from casuistry towards principles or to increase your weighting of your future circumstances or other’s circumstances. I’m not clear on how a good visualization technique makes for an ideal, though.