On 19 Aug 2009, at 02:31, Brent Meeker wrote:
> Bruno Marchal wrote:
>> This is not the point. The point is that if you develop a correct
>> argumentation that you are material, and that what we "see" around us
>> is material, then the arithmetical P. Jone(s) will also find a
>> argumentation that *they* are material, and that what they see is
>> material. The problem is that if you are correct in "our physical
>> reality" their reasoning will be correct too, and false of course.
>> then your reasoning has to be false too.
>> The only way to prevent this consists in saying that you are not
> Why can't I just say I'm not Turing emulated? It seems that your
> argument uses MGA to
> conclude that no physical instantaion is needed so Turing-
> emulable=Turing-emulated. It
> seems that all you can conclude is one cannot *know* that they have
> a correct argument
> showing they are material. But this is already well known from
> "brain in a vat" thought
OK. But this seems to me enough to render invalid any reasoning
leading to our primitive materiality.
If a reasoning is valid, it has to be valid independently of being
published or not, written with ink or carbon, being in or outside the
UD*. I did not use MGA here.
>> But if you are correct in your reasoning, the simulated you has to be
>> correct to. It is the same reasoning.
>> Or you have a special sense making you know that you are the "real"
>> one, but either that special sense is Turing emulable and your
>> doppelganger inherit them, or it is not Turing emulable, and you
>> better should say "no" to the doctor, because you would loose that
> Or it is a relation to the rest of the world and you can say yes so
> long as the doctor
> maintains your relations to the rest of the world - i.e. physically
> instantiates your
This means, by definition of the "generalized brain", that you have
not choose the right substitution level/context.
You can say yes because the doctor substitute correctly a *part* of
your brain, but you have to introduce a non computational element in
the environment to prevent its appearance in the mathematical UD*.
You do *seem* to have a sort of point here, though. You provide a
situation where comp is false, yet we can say"yes" to the doctor. But
in this case your survival is no more "qua computatio". Your survival
comes from the fact that your consciousness supervene on some magical
(non turing emulable) property of the material moon (say), and that
your doctor did not give you an artificial brain, just an artificial
part of your brain. This is no more comp or CTM. It is not different
than saying yes to the doctor because you believe there is a God who
will save your soul and put it back in the reconstitution.
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