George Levy wrote:
I have been following the latest very scholarly exchange involving different logical models in relation to the MWI, however I fail to see how it relates to my own perception of the world and my own consciousness unless I think according to those formal systems which I think is unlikely.
Using different logical models to describe possible worlds is interesting but isn't it true that if the problem of consciousness (as an observer, and definer, for these worlds) is to be addressed, then the only logic that matters is the one in my, or in your, own head? Of all these logical models which one is the "right" one? Are all of them "right?"
One thing is sure. Those modal logics are right for the consistent machines.
This is essentially what Godel (followed by Lob, ...) proves.
The rest is a matter of definition.
Can we find those logic by pure introspection? The S4 first person: yes (it
happens all the time from Heraclite to "toposes" ...
The G and G* logics? Not at all, they formalize by construction the most
counter-intuitive feature of the computationalist hypothesis.
When Copernicus formulated the heliocentric system, he didn't go around saying that a "new" logic had to be used to explain the central position of the sun. He simply used a physical model. People just had to accept the new paradigm that the Earth "moves" even though they do not feel the Earth move. Can't we just accept the fact that the world - and our consciousness - "split" or "merge" even though we do not feel them "split" and "merge?" It seems to me that if we define a good physical model, then classical probability could do the job of formulating the decision theory desired by Wei.
I think all the problem relies in the question "what is a physical model"?
Even what is a "physical reality"? Does that exists in some absolute sense?
With the comp hyp, that's doubtful, as I am used to argue.
I think this is coherent with your relativism, as we concluded before,
independently of comp!