You’re confused about probability, causality in QM, and anthropics. (Note in particular that your objection can’t be particular to MWI, since even in a collapse theory, the wacky things could happen).
MWI seems to me to eliminate the prior state from having an influence on the next state of my language machine.
The current state of your brain corresponds to a particular (small neighborhood of) configurations, and most of the wavefunction-mass that is in this neighborhood flows to a relatively small subset of configurations (i.e. ones where your next sentence is in English, or gibberish, rather than in perfect Klingon); this, precisely, is what causality actually means.
Yes, there is some probability that quantum fluctuations will cause your throat cells to enunciate a Klingon speech, without being prompted by a patterned command from your brain. But that probability is on the order of 10^{-100} at most.
And there is some probability, given the structure of your brain, that your nerves would send precisely the commands to make that happen; but given that you don’t actually know the Klingon speech, that probability too is on the order of 10^{-100}.
The upshot of MWI in this regard is that very few of your future selves will see wacky incredibly-improbably-ordered events happen, and so you recover your intuition that you will not, in fact, see wacky things. It’s just that an infinitesimal fraction of your future selves will be surprised.
You’re confused about probability, causality in QM, and anthropics. (Note in particular that your objection can’t be particular to MWI, since even in a collapse theory, the wacky things could happen).
The current state of your brain corresponds to a particular (small neighborhood of) configurations, and most of the wavefunction-mass that is in this neighborhood flows to a relatively small subset of configurations (i.e. ones where your next sentence is in English, or gibberish, rather than in perfect Klingon); this, precisely, is what causality actually means.
Yes, there is some probability that quantum fluctuations will cause your throat cells to enunciate a Klingon speech, without being prompted by a patterned command from your brain. But that probability is on the order of 10^{-100} at most.
And there is some probability, given the structure of your brain, that your nerves would send precisely the commands to make that happen; but given that you don’t actually know the Klingon speech, that probability too is on the order of 10^{-100}.
The upshot of MWI in this regard is that very few of your future selves will see wacky incredibly-improbably-ordered events happen, and so you recover your intuition that you will not, in fact, see wacky things. It’s just that an infinitesimal fraction of your future selves will be surprised.
Thanks, this really helps to clarify the picture for me.