Good questions. I am bracing for Bruno's reply to include something about the dependence on Church Thesis and "effective computability" to put some constraints on S_c, more than finiteness. My question on the weakness of the finiteness of S_c was valid even when giving "the benefit of the doubt" to the doctor and his trustworthiness, and independent of methods of instantiation.
Tom David Nyman wrote: > Tom Caylor wrote: > > 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). > > 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? > > David > > > > 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: > > > > > > 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/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to email@example.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list -~----------~----~----~----~------~----~------~--~---