Abram Demski wrote: > Bruno, > > It seems to me that this runs head-on into the problem of the > definition of time... > > Here is my argument; I am sure there will be disagreement with it. > > Supposing that Alice's consciousness is spread out over the movie > billboards next to the train track, there is no longer a normal > temporal relationship between mental moments. There must merely be a > "time-like" relationship, which Alice experiences as time. But, then, > we are saying that wherever a logical relationship exists that is > time-like, there is subjective time for those inside the time-like > relationship. > > Now, what might constitute a time-like relationship? I see several > alternatives, but none seem satisfactory. > > At any given moment, all we can be directly aware of is that one > moment. If we remember the past, that is because at the present moment > our brain has those memories; we don't know if they "really" came from > the past. What would it mean to put moments in a series? It changes > nothing essential about the moment itself; we can remove the past, > because it adds nothing.
You raise some good points. I think the crux of the problem comes from chopping a process up into "moments" and assuming that these infinitesimal, frozen slices preserve all that is necessary for time. It is essentially the same as assuming there is a "subsitution level" below which we can ignore causality and just talk about states. It seems like a obvious idea, but it is contrary to quantum mechanics and unitary evolution under the Schrodinger equation which was the basis for the whole idea of a multiverse and "everything happens". > > The connection between moments doesn't seem like a physical > connection; the notion is non-explanatory, since if there were such a > physical connection we could remove it without altering the individual > moments, therefore not altering our memories, and our subjective > experience of time. How do we know that? Memories and brain processes are distributed and parallel, which means there are spacelike separated parts of the process - and neural signals are orders of magnitude slower than light. Brent >Similarly, can it be a logical relationship? Is it > the structure of a single moment that connects it to the next? How > would this be? Perhaps we require that there is some function (a > "physics") from one moment to the next? But, this does not exactly > allow for things like relativity in which there is no single universal > clock. Of course, relativity could be simulated, creating a universe > that was run be a universal clock but whose internal facts did not > depend on which universal clock, exactly, the simulation was run from. > My problem is, I suppose, that any particular definition of "timelike > relationship" seems too arbitrary. As another example, should any > probabilistic elements be allowed into physics? In this case, we don't > have a function any more, but a relation-- perhaps a relation of > weighted transitions. But how would this relation make any difference > from inside the universe? > > --Abram > > On Wed, Nov 26, 2008 at 4:09 AM, Bruno Marchal <[EMAIL PROTECTED]> wrote: >> MGA 3 >> >> It is the last MGA ! >> >> I realize MGA is complete, as I thought it was, but I was doubting this >> recently. We don't need to refer to Maudlin, and MGA 4 is not necessary. >> Maudlin 1989 is an independent argument of the 1988 Toulouse argument (which >> I present here). >> Note that Maudlin's very interesting "Olympization technic" can be used to >> defeat a wrong form of MGA 3, that is, a wrong argument for the assertion >> that the movie cannot be conscious. (the argument that the movie lacks the >> counterfactual). Below are hopefully correct (if not very simple) argument. >> ( I use Maudlin sometimes when people gives this non correct form of MGA 3, >> and this is probably what makes me think Maudlin has to be used, at some >> point). >> >> >> >> MGA 1 shows that Lucky Alice is conscious, and MGA 2 shows that the >> "luckiness" feature of the MGA 1 experiment was a red herring. We can >> construct, from MEC+COMP, an home made lucky rays generator, and use it at >> will. If we accept both digital mechanism, in particular Dennet's principle >> that neurons have no intelligence, still less prescience, and this >> *together with* the supervenience principle; we have to accept that Alice >> conscious dream experience supervenes on the projection of her brain >> activity movie. >> >> Let us show now that Alice consciousness *cannot* supervene on that >> *physical* movie projection. >> >> >> I propose two (deductive) arguments. >> >> 1) >> >> Mechanism implies the following tautological functionalist principle: if, >> for some range of activity, a system does what it is supposed to do, and >> this before and after a change is made in its constitution, then the change >> does not change what the system is supposed to do, for that range of >> activity. >> Example: >> - A car is supposed to broken but only if the driver is faster than 90 >> miles/h. Pepe Pepito NEVER drives faster than 80 miles/h. Then the car is >> supposed to do what she is supposed to do, with respect of its range of >> activity defined by Pepe Pepito. >> - Claude bought a 1000 thousand processors computer. One day he realized >> that he used only 990 processors, for his type of activity, so he decided to >> get rid of those 10 useless processors. And indeed the machine will satisfy >> Claude ever. >> >> - Alice has (again) a math exam. Theoreticians have correctly predict that >> in this special circumstance, she will never use neurons X, Y and Z. Now >> Alice go (again, again) to this exam in the same condition, but with the >> neurons X, Y, Z removed. Again, not only will she behaved like if she >> succeed her exam, but her consciousness, with both MEC *and* MAT still >> continue. >> The idea is that if something is not useful, for an active process to go on, >> for some range of activity, then you can remove it, for that range of >> activity. >> >> OK? >> >> Now, consider the projection of the movie of the activity of Alice's brain, >> "the movie graph". >> Is it necessary that someone look at that movie? Certainly not. No more than >> it is needed that someone is look at your reconstitution in Moscow for you >> to be conscious in Moscow after a teleportation. All right? (with MEC >> assumed of course). >> Is it necessary to have a screen? Well, the range of activity here is just >> one dynamical description of one computation. Suppose we make a hole in the >> screen. What goes in and out of that hole is exactly the same, with the hole >> and without the hole. For that unique activity, the hole in the screen is >> functionally equivalent to the subgraph which the hole removed. Clearly we >> can make a hole as large as the screen, so no need for a screen. >> But this reasoning goes through if we make the hole in the film itself. >> Reconsider the image on the screen: with a hole in the film itself, you get >> a "hole" in the movie, but everything which enters and go out of the hole >> remains the same, for that (unique) range of activity. The "hole" has >> trivially the same functionality than the subgraph functionality whose >> special behavior was described by the film. And this is true for any >> subparts, so we can remove the entire film itself. >> >> Does Alice's dream supervene (in real time and space) on the projection of >> the empty movie? >> >> Remark. >> 1° Of course, this argument can be sum up by saying that the movie lacks >> causality between its parts so that it cannot really be said that it >> computes any thing, at least physically. The movie is just an ordered record >> of computational states. This is neither a physical computation, nor an >> (immaterial) computation where the steps follows relatively to some >> universal machine. It is just a description of a computation, already >> existing in the Universal Deployment. >> 2° Note this: If we take into consideration the relative destiny of Alice, >> and supposing one day her brain broke down completely, she has more chance >> to survive through "holes in the screen" than to the "holes in the film". >> The film contains the relevant information to reconstitute Alice from her >> brain description, contained on this high resolution film. Keeping comp, and >> abandoning the physical supervenience thesis, means that we do no more >> associate consciousness, neither on the movie, NOR on the brain special >> activity in a computation, but to the computation itself directly. A brain, >> and even a film, will "only" be a way to make bigger the probability >> for a consciousness to manifest itself relatively to a "probable" universal >> computational history. >> Strictly speaking, running the movie dimimish Alice chance to have her >> conscious experience (life) continue, at least relatively to you, because of >> the many scratches the projector makes on the pellicle, which remove >> relevant information for a safe reconstitution later (again relatively to >> you). >> >> >> 2) >> >> I give now what is perhaps a simpler argument >> >> A projection of a movie is a relative phenomenon. On the planet 247a, nearby >> in the galaxy, they don't have screen. The film pellicle is as big as a >> screen, and they make the film passing behind a stroboscope at the right >> frequency in front of the public. But on planet 247b, movies are only for >> travellers! They dress their film, as big as those on planet 247a, in their >> countries all along their train rails with a lamp besides each frames, which >> is nice because from the train, through its speed, you get the usual 24 >> frames per second. But we already accepted that such movie does not need to >> be observed, the train can be empty of people. Well the train does not play >> any role, and what remains is the static film with a lamp behind each frame. >> Are the lamps really necessaries? Of course not, all right? So now we are >> obliged to accept that the consciousness of Alice during the projection of >> the movie supervenes of something completely inert in time and space. This >> contradicts the *physical* supervenience thesis. >> >> >> Exercises. >> >> a) Someone could propose an alternate argument that a movie does not compute >> (and so consciousness does supervene on it) by alluding to the lack of >> causality in the movie: the movie does not handle the counterfactual >> existing implicitly in computations (physical or not). Use Maudlin's >> Olympization technic to refute that argument. >> b) Make fun by using a non dreaming Alice. Shows that the movie (film or >> screen) graph border is needed to get the accidental zombies (the puppet). >> >> And then the "important" exercise (the original goal). >> c) Eliminate the hypothesis "there is a concrete deployment" in the seventh >> step of the UDA. Use UDA(1...7) to define properly the computationalist >> supervenience thesis. Hint: reread the remarks above. >> Have a good day. >> >> >> Bruno >> >> >> http://iridia.ulb.ac.be/~marchal/ >> 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 PROTECTED] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list?hl=en -~----------~----~----~----~------~----~------~--~---
