On Thu, Dec 29, 2011 at 9:47 AM, Bruno Marchal <marc...@ulb.ac.be> wrote:
> > Which computation? I don't see any computation in the projection of the > computation-movie. The Boolean graph nodes are broken. The light patterns > is exactly the same, with the boolean graph turned, or not, upside down. > You argument seems to rely on non relevant (with respect to the possible > computation) idiosyncracies of this thought experience implementation. I > will think about a version of MGA making this more obvious. > OK, I think I see where my error lies. I thought the absurdity arose later in the argument than it actually does. I see that by my reasoning we would have conscious supervening on the particular physical system and not the "computation" itself, which would contradict comp. If we "extract" the computation from the glass/node system in the form of the film, then by comp consciousness should supervene on the film, when clearly it cannot. Is that roughly what you are saying? > > It *does *matter for the computation what the light lands on. > > > But what is the computation in this case? > > > > This doesn't violate 323, or comp. It means that the whole system > (crystal/glass+film) must be taken into account in your analysis. > > > The whole system is considered, and then changed in a way which does not > change the physical activity, except for operating nodes which are > retreived, and this to show that the physical activity does not implement > the computation, but is only a mimicking of non relevant appearances > associated accidentally with the "original computation". > > > > It is no better than taking half of the brain and ignoring the other half. > It isn't a matter of substitution level. > > > OK. But you have to explain me the role of the broken node, in the > computation, or even in the light patterns. You might try, as an exercise > to refute your own argument by changing the original device. > I will think about it. > > > >> >> >> >> >> >> >>> >>> >>> >>> Let me restate my concern: Consciousness supervenes on the optical >>> graph+the recording, *even when the nodes are completely disconnected. *It >>> is true that "most of the work" is being done by the recording, but not all >>> of the work. The optical graph still matters, and the "physical activity" >>> of the system is not solely provided by the recording, as it still depends >>> on how the projected light interacts (physically) with the glass/crystal >>> surface. >>> >>> >>> But this is no more relevant in term of the computation, which is >>> supposed to be a copy of the brain processing at the right level or below. >>> >>> >>> >>> There is a point in the argument at which you ignore the glass/crystal >>> system and focus solely on the movie/recording, claiming that Alice's >>> consciousness supervenes on the movie/recording. But this is false. *At >>> no point *does Alice's consciousness supervene on the recording, *not >>> even *when the nodes are completely disconnected. >>> >>> >>> Yes. That's why it is a reductio ad absurdum. >>> >> >> Its a reductio ad absurdum only if you artificially ignore the >> interaction between the projected light and the crystal medium and lasers. >> Because consciousness supervenes on crystal/glass/nodes+film, it is not >> meaningful to make this move. >> >> > What is removed does not change the light pattern. The nodes are broken > and play no role in that computation, in case we could find one (as opposed > to find just a description of a computation, for which the nodes are also > irrelevant). > > > > > Consciousness changes do not imply film changes (even though the converse >> may well be true). You have isolated a subsystem from the machine, mistaken >> this subsystem for being sufficient for consciousness to supervene on -- >> little wonder an absurd conclusion follows! >> >> >> I could because all this is supposed to be done below the substitution >> level. >> > > I understand that, but I don't understand how it addresses my point. > > > If the boolean graph is no more working, to insist we don't remove the > nodes gives them a special role not accounted in original computation, > which can be said to exist (relatively to us) by the fact the nodes did > operate the relevant elementary computable steps defining the (relative) > implementation of the computation. The role you give to the node, for > making the projection conscious seems magical and unrelated to the original > computation. > > > > >> >> >> >> >> I am trying to think of an analogy to another system which would make my >> argument clearer (and in the process learning how tricky the concept of >> supervenience can be). >> >> >> >> Actually, I do the same. I search a system where I can make it clearer >> why the idiosyncrasies of the movie-graph are simpler to evacuate. >> But in the present case, it seems rather obvious to me that the absurdity >> is already there, before replacing the glass+smoke by a usual screen. There >> is already no more computations, we can already use the stroboscopic >> argument to make that absurd. >> > > I am not familiar with the stroboscopic argument. > > > It is an argument used to show (if that was necessary) that a movie of a > computation is not a computation, nor even a well defined physical reality. > Instead of moving the film behind a lamp, we move the (stroboscopic) lamps > and the observer along the film. Then the existence of a movie is shown to > be relative to an observer, making the idea that a consciousness supervene > on the movie non sensical. I think this should work also with the situation > where the broken nodes are not removed. > Such an argument avoid some special tailored critics based on that type of > thought experiment, like the heap sand critics (which by itself leads to > the absurd notion of partial zombie, which some materialist accepts, but > just as way to avoid the consequence of comp). Anyway, the stroboscopic > argument shows that a projection of a movie is not even a well defined > physical events, as needed for a primitive supervenience thesis. > > Bruno > > > > > >> >> 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 >> everything-list+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/everything-list?hl=en. >> > > > > -- > Joseph Knight > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To post to this group, send email to firstname.lastname@example.org. > To unsubscribe from this group, send email to > everything-list+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/everything-list?hl=en. > > > 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 > everything-list+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/everything-list?hl=en. > -- Joseph Knight -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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