All of Howard Halim's Comments + Replies

Isn't this identical to the proof for why there's no general algorithm for solving the Halting Problem? The Halting Problem asks for an algorithm A(S, I) that when given the source code S and input I for another program will report whether S(I) halts (vs run forever). There is a proof that says A does not exist. There is no general algorithm for determining whether an arbitrary program will halt. "General" and "arbitrary" are important keywords because it's trivial to consider specific algorithms and specific programs and say, yes, we can determine that this specific program will halt via this specific algorithm. That proof of the Halting Problem (for a general algorithm and arbitrary programs!) works by defining a pathological program S that inspects what the general algorithm A would predict and then does the opposite. What you're describing above seems almost word-for-word the same construction used for constructing the pathological program S, except the algorithm A for "will this program halt?" is replaced by the predictor "will this person one-box?". I'm not sure that this necessarily matters for the thought experiment. For example, perhaps we can pretend that the predictor works on all strategies except the pathological case described here, and other strategies isomorphic to it.

This objection to Newcomb-like problems (that IF I'm actually predicted, THEN what I think I'd do is irrelevant - either the question is meaningless or the predictor is impossible) does get brought up occasionally, and usually ignored or shouted down as "fighting the hypothetical".    The fact that humans don't precommit, and if they could the question would be uninteresting, is pretty much ignored. Replacing the human with a simple, transparent, legible decision process makes this a lot more applicable, but also a lot less interesting.   Whatever can be predicted as one-boxing makes more money, and per the setup, that implies actually one-boxing.  done.

If you precommit to act this way, then it's not the case that [the predictor predicts that you wouldn't take the small box regardless of what you see in the big one] (since you do take it if the big box is full, so in that case you can't be predicted not take the small box). By the stated algorithm of box-filling, this results in the big box being empty. The predictor is not predicting what happens in actuality, it's predicting what happens in the hypothetical situation where the big box is full (regardless of whether this situation actually takes place), and what happens in the hypothetical situation where the big box is empty (also regardless of what happens in reality). The predictor is not deciding what to do in these hypothetical situations, it's deciding what to do in reality.