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:
NOT COMP or NOT PHYSICAL SUPERVENIENCE
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
http://iridia.ulb.ac.be/~marchal/
