Hm, so you're saying that anticipation isn't a primitive, it's just part of one's decision-making process. But isn't there a sense in which I ought to expect the Born rule to hold in ordinary circumstances? Call it a set of preferences that all humans share — we care about futures in proportion to the square of the modulus of their amplitude (in the universal wavefunction? in the successor state to our Everett branch?). Do you have an opinion on exactly how that preference works, and what sorts of decision problems it applies to?
Induction. You have uncertainty about the extent to which you care about different universes. If it turns out you don't care about the born rule for one reason or another the universe you observe is an absurdly (as in probably-a-Boltzmann-brain absurd) tiny sliver of the multiverse, but if you do, it's still an absurdly tiny sliver but immensely less so. You should anticipate as if the born rule is true, because if you don't almost only care about world where it is true, then you care almost nothing about the current world, and being wrong in it doesn't ma...
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