Maybe it’s better not to talk about causal networks. Let’s use an AIXI-like setup instead. The EDT agent starts with a Solomonoff prior over all computable functions that Omega could be. Part of the setup of Newcomb’s problem is that Omega convinces you that it’s a very good predictor, so some series of trials takes place in which the EDT agent updates its prior over what Omega is. The posterior will be concentrated at computable functions that are very good predictors. The EDT agent then reasons that if it two-boxes then Omega will predict this and it won’t get a good payoff, so it one-boxes.
But in the transparent-box variant, the EDT agent knows exactly how much money is in box A before making its decision, so its beliefs about the contents of box A do not change when it updates on its counterfactual decision.
If you want to change what you want, then you’ve decided that your first-orded preferences were bad. EDT recognizing that it can replace itself with a better decision theory is not the same as it getting the answer right; the thing that makes the decision is not EDT anymore.
We don’t usually let decision theories make precommitments. That’s why CDT fails Newcomb’s problem. I think CDT and EDT both converge to something like TDT/UDT when allowed to precommit as far in advance as desirable.
Maybe it’s better not to talk about causal networks. Let’s use an AIXI-like setup instead. The EDT agent starts with a Solomonoff prior over all computable functions that Omega could be. Part of the setup of Newcomb’s problem is that Omega convinces you that it’s a very good predictor, so some series of trials takes place in which the EDT agent updates its prior over what Omega is. The posterior will be concentrated at computable functions that are very good predictors. The EDT agent then reasons that if it two-boxes then Omega will predict this and it won’t get a good payoff, so it one-boxes.
But in the transparent-box variant, the EDT agent knows exactly how much money is in box A before making its decision, so its beliefs about the contents of box A do not change when it updates on its counterfactual decision.
Ah. I guess we’re not allowing EDT to make precommitments?
If you want to change what you want, then you’ve decided that your first-orded preferences were bad. EDT recognizing that it can replace itself with a better decision theory is not the same as it getting the answer right; the thing that makes the decision is not EDT anymore.
We don’t usually let decision theories make precommitments. That’s why CDT fails Newcomb’s problem. I think CDT and EDT both converge to something like TDT/UDT when allowed to precommit as far in advance as desirable.