Tom Caylor wrote:

> can be expressed by a finite number, since the substitution itself can
> be expressed by a finite number (whatever is written on the tape/CD or
> other storage/transmitting device).

Does your 'interpretation' of 'Yes doctor' leave open all assumptions
about actual *instantiation* of S_p? You refer above to the 'tape/CD or
other storage/transmitting device'. Is an additional act of faith
required such that we trust the doctor not merely to leave S_p to
gather dust on a shelf? Or, if he does cause the instantiation of S_p
(even assuming it to be equivalent to S_c) in terms of some
unconstrained choice among arbitrarily many machine 'architectures'
(electronic, hydraulic, mechanical, Platonic, you-name-it) I am to
further trust that my experience will remain invariant to the actual
physical behaviour thus enacted? Or is the assumption of YD within a
'comp' that additionally assumes AR+CT supposed to subsume all the
above issues, and if so why?

How far do we up the ante here?


> As I remember it, my interpretation/expansion of the "Yes Doctor"
> assumption is that 1) there is a (finite of course) level of (digital)
> substitution (called the "correct level of substitution") that is
> sufficient to represent "all that I am", and "all that I could be if I
> hadn't undergone a substitution", and 2) we (including the doctor)
> cannot know what the correct level of substitution is, therefore we
> have to gamble that the doctor will get it right when we say "Yes
> Doctor".
> Suppose that the level of substitution actually *performed* by the
> Doctor is S_p.  Denote the *correct* level of substitution S_c.  S_p
> can be expressed by a finite number, since the substitution itself can
> be expressed by a finite number (whatever is written on the tape/CD or
> other storage/transmitting device).  We know what S_p is and it is a
> *fixed* finite number. But since S_c (*correct* level) is totally
> unknowable, all we "know" about it is our assumption that it is finite.
>  The next *obvious* step in the logical process is that the probability
> that S_p >= S_c is infinitesimal.  I.e. the probability that the doctor
> got it right is zilch.  This is because most numbers are bigger than
> any fixed finite number S_p.
> So it seems that our step of faith in saying Yes Doctor in not well
> founded.  It's definitely a bad bet.
> It seems that we need a stronger statement than S_c is finite.
> Tom
> Bruno Marchal wrote:
> > Le 21-août-06, à 07:11, Stathis Papaioannou a écrit :
> >
> > >
> > > It seems to me that there are two main sticking points in the
> > > discussions on
> > > several list threads in recent weeks. One is computationalism: is it
> > > right or wrong?
> > > This at least is straightforward in that it comes down to a question
> > > of faith, in the
> > > final analysis, as to whether you would accept a digital replacement
> > > brain or not
> > > (Bruno's "yes doctor" choice).
> >
> > Yes. Unfortunately this gives not a purely operational definition of
> > comp.
> > Someone could say yes to the doctor, just thinking that God exists, and
> > that God is infinitely Good so that he will manage to resuscitate him
> > through the reconstitution (he believes also God is infinitely
> > powerful).
> > So comp is really the belief that you can survive with an artificial
> > brain *qua computatio", that is, through the respect of some digital
> > relation only.
> >
> >
> >
> > > The other sticking point is, given computationalism
> > > is right, what does it take to implement a computation? There have
> > > been arguments
> > > that a computation is implemented by any physical system (Putnam,
> > > Searle, Moravec)
> > > and by no physical system (Maudlin, Bruno Marchal).
> >
> >
> >
> > OK. To be sure Maudlin would only partially agree. Maudlin shows (like
> > me) that we have:
> >
> >
> > But apparently Maudlin want to keep physical supervenience, and thus
> > concludes there is a problem with comp. I keep comp, and thus I
> > conclude there is a problem with physical supervenience.
> > Actually I just abandon the thesis of the physical supervenience, to
> > replace it by a thesis of number-theoretical supervenience.
> >
> >
> > > The discussion about Platonism
> > > and the ontological status of mathematical structures, in particular,
> > > relates to this
> > > second issue. Bruno alludes to it in several papers and posts, and
> > > also alludes to his
> > > "movie graph argument", but as far as I can tell that argument in its
> > > entirety is only
> > > available in French.
> >
> >
> > That's true. I should do something about that. I don't feel it is so
> > urgent in the list because there are more simple problem to tackle
> > before, and also, most "MWI", or "Everything"-people can easily imagine
> > the UD doesn't need to be run. But this is a subtle problem for those
> > who have faith in their uniqueness or in the uniqueness of the world.
> > Still you are right, I should write an english version of the movie
> > graph.
> > 
> > Bruno
> > 
> > 
> >

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