Bruno, So, basically, you are saying that I'm offering an alternative argument against materialism, correct? Supposing that reality has a purely mathematical basis eliminates the problem, because removing the past is like removing the number 13.
You say that the argument by counterfactuals won't work, thanks to Olympization... I don't know what Olympization is, so I'd like to hear the argument. As for the remainder of your comments, I suppose I'll just have to go read UDA. --Abram On Thu, Nov 27, 2008 at 3:37 PM, Bruno Marchal <[EMAIL PROTECTED]> wrote: > Hi Abram, > > On 27 Nov 2008, at 20:02, 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. > > Assuming MAT (and MEC). OK. > > > 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. > > With MAT, (in a block view or not). OK. > > > > > 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. > > With MAT! As Stathis said, once consciousness supervenes on mathematical > computations (up to some equivalence class), you can no more remove a past > than you can remove the number 13 from elementary arithmetic. > > > > > 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. > > All right. > > > > 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? > > It is here that we have to take into account what I think to be a major > discovery, if not THE first big(**) discovery of humanity: the discovery > of the (mathematical) Universal Machine (of Turing, if you want, but with > Church thesis it is considerably more general). > That concept makes it possible to define a "space" of all computations. It > is defined unambiguously by the Universal Dovetailer, a program itself. Or > equivalently by the set of sigma_1 sentences and their proofs (note that the > false sigma_1 sentences inherit infinite proofs). > Now, consider some trace of that program. It executes all computations. But > (see the UDA), from our personal point of view, even between just two > distinguishable computational states, there will be a continuum of > computations going through those states, if only due to the "dumbness" of > the UD, who re-execute each step of any computation by dovetailing them on > all "real" oracle. And MEC predict that this "mutiplication" of computations > appearing below our substitution level is indirectly observable. > > > > But, this does not exactly > allow for things like relativity in which there is no single universal > clock. > > (Sure, but we were trying to suppose here only MEC + MAT (not MEC + MAT + > relativity). And this points to a little weakness of the second argument I > gave. > But I would find only funny to just conclude that the falsity of relativity > would safe "MAT". That would be a type of ad hoc move I was hoping to > exclude in some dreamy "MGA 5" some posts ago. > > > 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. > > You have to read the UDA here I'm afraid: no "emulable physical reality" can > save the problem. With MEC, "physical reality" has to emerge from ALL > emulable histories, and this, as viewed by any universal machine, is really > an infinite sum. That sum is hardly emulable, a priori, but I agree that > quantum mechanics seems to show that such a sum is perhaps emulable (albeit > with exponential slow down) by the sharable indeterminate part making our > probable sharable neighborhood. > MEC has everything to justify it, or to refute it (in which case the success > of quantum computing would confirm or refute MEC). Up to now, QM confirms > MEC (I can say more precise technical things here if interested). > > > > My problem is, I suppose, that any particular definition of "timelike > relationship" seems too arbitrary. > > There is a big difference between first person non sharable time, and > sharable local (clock measurable) time. The first you experience, the second > you guess, and you guess it only from an implicit bet on your own > > consistency. It makes a big "modal" difference. > > > > 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? > > > We are supported by infinity(*) of computations. We can only bet on our > most probable "histories", above our level of constitution. Those historie > which can multiplie themselves from below, and thus in front of pure > probabilistic event (noise) can win the measure game (on the computations or > the OMs). The question is: can we explain from MEC, as we have too, why, as > we can see empirically, the "probabilities" can also be subtracted. To we > get here too classical mechanics in the limit? Open problem of course. > Now the crazy thing is that we can already (thanks to Gödel, Löb, Solovay > ...) interview a (Lobian) universal machine on that subject, and she gives a > shadow of reason (and guess!) why indeed subtraction occurs. And thanks to > the Solovay split between G (the provable part of self-reference, and G*, > the true but unprovable part of self-reference, some intensional variant of > G and G* split temselves into the sharable physics (indeteminate quanta) and > unsharable physics (the qualia? the perceptible field, what you can only be > the one to confim: a bit like being the one in Moscow after a > self-duplication experiment). > > Bruno > > (*) Even infinitIES, from the "third person point of view on the first > person points of view. Hmmm do you know the first person comp indeterminacy? > (step 3 of UDA). > (**) The second BIG discovery being the quantum computer ! (don't hesitate > to use grain salts if it helps to swallows what I say). of course "nature" > made those discoveries before us. Well, with MEC we have to consider that > elementary arithmetic did those "discoveries" even out of time and space. > > > > > > 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/ > > > > > > > > > > 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 -~----------~----~----~----~------~----~------~--~---
