John Clark wrote:
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> >>It two things can be exchanged and no change can be detected
> by the
> >>outside world then the two things are identical.
> >christophe delriviere <firstname.lastname@example.org
> >Ah, but we are not in quantum mecanics here, brains are
> >objects, so we can track their positions in space-time.
> How can you track them? If your brain and mine are identical then
> there is no
> way to determine if they've switched positions or not, and it wouldn't
> if they did.
your concept of identity is only valuable for a time in witch occur no interactions between the respective brains and their environments. Very Very short time, probably equal to zero in the universe. With what kind of magic are you able to switch the two brains without interacting with them?
> >A brain is also strongly defined by his position.
> How? The input position of the sense organs is the only thing that's
> important, the only restriction is that the sense organs are not so
> far away
> that time delays caused by the speed of light start to become
No, if we discuss of human brain, all the brain can also be viewed as a big sense organ.It receive for example gamma rays from his environment. the gamma rays received in some points of the brain are function of his position in the space-time. the gamma rays are inducing reactions that obviously can change the configuration of a brain.
> A brain by itself has no way to determine it's position in space, or
> passage of time for that matter. I could stop your brain for a
> years, speed it up by a factor of a billion, or even make it run
> backward and
> you'd never notice a thing. In the future "people" might not know or
> care where
> their brain was, or if they were operating on their primary or backup
This is true if you are able to isolate *completly* a brain from the universe of reference and simulate the complete fabric of this universe inside this universe. Are you able to propose facts that it is possible to construct such simulator?(universe of reference = where is implemented the simulator)
you are asking for a complete identity of brains at a quantum level and perhaps beyond. I seriously doubt there is a substantial probability that such things can occur or are implementable.
I think a concept of identity form a brain as to take in consideration
In such view, a brain is then defined by the total configuration of the universe (the configuration of the brain and the configuration of his environment).