Re: A Questionnaire for Bill Taylor
Le 12-mai-05, à 19:14, Peter D Jones a écrit : I don't see why. Surely what is beng asserted is that there is a set of physically real universes, and it is a subset of logically possible universes (Platonia) -- but logically possible universes are not real in any sense, they are just an abstrction. But logically possible universes are certainly real in one sense: as being logically possible. Or as being logically consistent. If they are furthermore enough rich in complexity to have abstract inhabitant, it is reasonable or plausible (at least) that for those inhabitants their abstract universe will look as it is real. And this will make sense if, furthermore again, their relative abstract computational continuations have the right measure. And theoretical computer science can justify the existence of such relative measure. And, finally, if such mathematical measure leads to the verified empirical measure, then, frankly, it seems to me that materialism in physics begins to look like ... late vitalism in 19th century biology. (And then my thesis shows that the mathematical measure extract from computer science looks sufficiently like the quantum measure to considerate that the case for a scientific materialism is at least premature. To sum up: real is just (abstract) consistency as seen from inside. Bruno http://iridia.ulb.ac.be/~marchal/
Re: Bruno's Thesis
Le 12-mai-05, à 19:33, Peter D Jones a écrit : but physics is a subset of Platonia -- our space has 3 macroscopic dimensions. Platonia contains spaces of every dimensionallity. I think it is misleading to consider physics as a subset of Platonia. As it is misleading to consider physical evoultion as one computational history among all comp histories. With the comp hyp, at least, physics can be shown to have a much more deep relationship with mathematical Platonia. Physics really emerges from the whole platonia structure, and like you are obliged to take into account all possible path of an electron to compute the probability that it will strikes some region on a screen, with comp you are obliged in fine to take into account all the topology space can take, and then also all possible fine grained logical consistent computational histories. An *image* which is related is that Platonia is an abstract volume and physics is the border of that volume as seen from its interior. Physics would be a sort of derivative of psychology (computer science), and psychology would be some integral of physics. But at this stage it is only an analogy, which could hardly be made more precise without being much more technical. What I want to say is that the physical world is not just a part of platonia, it is mathematically related to the global structure of that Platonia. Bruno http://iridia.ulb.ac.be/~marchal/
Re: Many worlds theory of immortality
What is the difference between a simulation and a representation? Is it just that a representation is a rather poor simulation, one that doesn't talk back to you, like a film? Is there a sharp dividing line between the two, or is it a continuum? --Stathis Papaioannou From: Saibal Mitra [EMAIL PROTECTED] To: everything everything-list@eskimo.com Subject: Re: Many worlds theory of immortality Date: Fri, 13 May 2005 03:11:21 +0200 One could say that the brain of some schizophrenic persons simulate other persons. I don't know if some of you have seen the film 'A Beautiful mind' about the life of mathematician Nash. In the film Nash was closely acquainted to persons that didn't realy exist. Only much later when he was treated for his condition did he realize that some of his close friends didn't really exist. One could argue that the persons that Nash was seeing in fact did exist (in our universe), precisely because Nash's brain was simulating them. Saibal Van: Stathis Papaioannou [EMAIL PROTECTED] Aan: [EMAIL PROTECTED]; [EMAIL PROTECTED] CC: everything-list@eskimo.com Verzonden: Thursday, May 12, 2005 03:25 PM Onderwerp: Re: Many worlds theory of immortality The obvious and sensible-sounding response to Jeanne's question whether it may be possible to access other universes through dreams or hallucinations is that it is not really any more credible than speculation that people can contact the dead, or have been kidnapped by aliens, or any other of the millions of weird things that so many seem to believe despite the total lack of supporting evidence. However, this response is completely wrong if MWI is correct. If I dream tonight that a big green monster has eaten the Sydney Opera House, then definitely, in some branch of the MW, a big green monster will eat the Sydney Opera House. Of course, this unfortunate event will occur even if I *don't* dream it, but I'm not saying that my dream caused it, only that I saw it happening. It might also be argued that I didn't really receive this information from another branch, but that it was just a coincidence that my dream matched the reality in the other branch. But seers don't see things by putting two and two together; they just, well, *see* them. And if I really could, godlike, enter at random another branch of the MW and return to this branch to report what I saw, how would the information provided be any different from my dream? The only difference I can think of is that with the direct method I would be more likely to visit a branch with greater measure, but I can probably achieve the same thing by trying not to think about green monsters when I go to sleep tonight. --Stathis Papaioannou I once read an article in, I believe, Time Magazine, about the relatively new field of neurotheology which investigates what goes on in the brain during ecstatic states, etc. One suggestion that intrigued me was that it may be possible that in such a state, and I believe that schizophrenics were also mentioned, that the brain is malfunctioning in such a way as to allow it to perceive states of reality other than that which the normal brain would perceive. In other words, the antenna (brain) is picking-up signals that are usually beyond the scope of the normal brain. I wondered if anyone could comment on this, and if there was any reason to even entertain the thought that perhaps some people have passed through a crack in the division between our universe or dimension, into perhaps another? I read this several years ago and wish that I could recall the details of the article, but I don't have it anymore. Jeanne _ MSN Messenger v7. Download now: http://messenger.ninemsn.com.au/ - Defeat Spammers by launching DDoS attacks on Spam-Websites: http://www.hillscapital.com/antispam/ _ REALESTATE: biggest buy/rent/share listings http://ninemsn.realestate.com.au
Re: many worlds theory of immortality
Le 13-mai-05, à 05:39, Lee Corbin a écrit : Brent writes I think that an observer must be physically instantiated - that seems well supported empirically. As it is used a observer moment seems to mean a unit of subjective experience. That there is an observer, i.e. something with continuity over many such subjective experiences, must be an inference or a construct within the theory. Personally, I would agree. But many here contend that abstract patterns---mathematical stings, really---can do *so* much cross- referencing and quoting of each other that a form of paste obtains that wields them in to something capable of having experiences. But a familiar abstract object, namely the real numbers between zero and one, evidently already does all of that (considering the decimal or binary expressions), and so I'm not sure what remains for the more abstruse inhabitants of Platonia to do. Such critics can be addressed to any block-universe view of physics, not just mathematical platonia. Yes, that's the simplest explanation! We have to suppose that physical objects continue to encode previously gained information in the default case. I don't know that we have to. I've know idealists who suppose that our memories are part of our immaterial spirits. But they have a hard time explaining the limitations of memory. Such idealists have a hard time being credible at all, if you ask me. But what John was perhaps saying---and what I would certainly claim along with all the adherents of observer-moments, I think---is that any particular version of you at any particular moment is not conscious of the facts encoded in all your memories. Hence the idea that an observer-moment is the net intersection across the multiverse and across other planetary systems of a particular sense-perception experience of a particular person. But if, for each subjective experience, there is no way to uniquely associate it with a sequence of subjective experiences, i.e. every such experience has many predecessors and successors, then I don't see how such sequences can constitute a particular person(s). I agree. That is, freed of memory, just how are all those subjective moments linked in a particular ordered sequence? I also agree with your statement, when *persons* (as you write) are being considered. I'll admit that there is something---but not very much---associated with a person that has nothing to do with the person's memories. It seems in these discussions that the existence of such sequences corresponding to a particular person, an observer, is taken for granted. It is a natural model given that observers are physical things - but it is problematic if physics is thrown out and you start from nothing but observer moments. Well said. A natural model does give us that observers are physical things, or at least *necessarily* instantiated in physical things. And I agree that starting from nothing but observer-moments won't take us any further than it took William James http://plato.stanford.edu/entries/james/ I can't blame the ancients and moderns up to the 19th century for being dualists. It seemed utterly impossible that mere atoms in motion could give rise to such as we. But the painful ---and painstaking---defeat of vitalism achieved finally in the 20th century leaves it the simplest hypothesis by far to say that we are machines. Our souls and we arise by natural means, just as do streams and mountains. Look at my recent posts to the FOR-LIST, which I have cc-send to the everything-list just two minutes ago. I agree the abandon of vitalism is a progress. And it is true that natural science has explained feature like self-reproduction, animal motion, energy transformation (sun - living matter) and so one. But it is just erroneous to conclude that the mind-body problem has been solved. And then if we are really digital machine, I offer a case that materialism will be abandoned from purely rational consideration. Matter? A lasting aristotelian superstition ... Observer-moments seems to arise simply from observers, Except that nobody has ever succeed in explaining how the 1-person observer moment can arise from any 3-person description of an observer. And myself and independently Maudlin has made a strong case why, with the comp hyp it is just impossible to make such a link. Reference can be found here: http://iridia.ulb.ac.be/~marchal/lillethesis/these/ node79.html#SECTION00130 and observers arise simply from highly intelligent mammals (or aliens) who can think about their own thinking. Unless you want (which is probably a good idea) to regard even photographic plates and other matter upon which impressions can be made as *observers*. Lee Bruno http://iridia.ulb.ac.be/~marchal/
Re: Which is Fundamental?
Le 12-mai-05, à 05:53, Lee Corbin a écrit : Bruno, I certainly wish you the absolute best of luck in deriving a law of physics from comp! Getting a version of string theory that afforded predictions would be as nothing in comparison from starting from incompleteness (in math) and deriving physics and observers. Many thanks, Lee. I have actually derived a quantum logic. I hope it is the good one, in von Neumann sense, which means that all the probabilities should be capable of being derived from that quantum logic (which you can seen as the logic of the yes-no experiments, or of the projections, or of the probability one/probability zero.). It is just a question of solving mathematical problems now. A rumor has circulated in Brussels that a (quite good) mathematical logician, M. Boffa, did solve one of the conjectures in my thesis. I contacted him and he confirms he has made some progress and that he would send me the solution by mail, but he dies before. I still don't know if the math are really hard, but the main (Solovay) technics clearly can't work. Some Dutch and Georgian logicians seems also to have try without success. A belgian student in math did find an error in my thesis, which has enriched the matter, because I have evacuated too early one of the most natural candidate for the arithmetical quantum logic. In any case the subject is rich, and I would say, that even if the comp-physics is different from the empircial physics, the comparison should be interesting: it would isolate the non-comp part of physics, and provides the first rational reason to believe in ... materialism. Bruno http://iridia.ulb.ac.be/~marchal/
Olympia's Beautiful and Profound Mind
Bruno recently urged me to read up on Tim Maudlin's movie-graph argument against the computational hypothesis. I did so. Here is my version of the argument. According to the computational hypothesis, consciousness supervenes on brain activity and the important level of organization in the brain is its computational structure. So the same consciousness can supervene on two different physical systems provided that they support the same computational structure. For example, we could replace every neuron in your brain with a functionally equivalent silicon chip and you would not notice the difference. Computational structure is an abstract concept. The machine table of a Turing Machine does not specify any physical requirements and different physical implementations of the same machine may not be comparable in terms of the amount of physical activity each must engage in. We might enquire: what is the minimal amount of physical activity that can support a given computation, and, in particular, consciousness? Consider that we have a physical Turing Machine that instantiates the phenomenal state of a conscious observer. To do this, it starts with a prepared tape and runs through a sequence of state changes, writing symbols to the tape, and moving the read-write as it does so. It engages in a lot of physical activity. By assumption, the phenomenal state supervenes on this physical computational activity. Each time we run the machine we will get the same phenomenal state. Let's try to minimise the amount of computational activity that the Turing Machine must engage in. We note that many possible pathways through the machine state table are not used in our particular computation because certain counterfactuals are not true. For example, on the first step, the machine might actually go from S_0 to S_8 because the data location on the tape contained 0. Had the tape contained a 1, it might have gone to S_10, but this doesn't obtain because the 1 was not actually present. So let's unravel the actual computational path taken by the machine when it starts with the prepared tape. Here are the actual machine states and tape locations at each step: S_0 s_8 s_7 s_7 s_3 s_2 . . . s_1023 t_0 t_1 t_2 t_1 t_2 t_3 . . . t_2032 Re-label these as follows: s_[0] s_[1] s_[2] s_[3] s_[4] s_[5] . . .s_[N] t_[0] t_[1] t_[2] t_[3] t_[4] t_[5] . . .t_[N] Note that t_[1] and t_[3] are the same tape location, namely t_1. Similarly, t_[2] and t_[4] are both tape location t_2. These tape locations are multiply-located. The tape locations t_[0], t[1], t[2], ..., can be arranged in physical sequence provided that a mechanism is provided to link the multiply-located locations. Thus t[1] and t[3] might be joined by a circuit that turns both on when a 1 is written and both off when a 0 is written. Now when the machine runs, it has to take account of the remapped tape locations when computing what state to go into next. Nevertheless, the net-effect of all this is that it just runs from left to right. If the machine just runs from left to right, why bother computing the state changes? We could just arrange for each tape location to turn on (1 = on) or off (0 = off) when the read/write head arrives. For example, if t_[2] would have been turned on in the original computation, then there would be a local mechanism that turns that location on when the read/write head arrives (note that t_[4] would also turn on because it is linked to t_[2]). The state S_[i] is then defined to occur when the machine is at tape location t_[i] (this machine therefore undergoes as many state changes as the original machine). Now we have a machine that just moves from left to right triggering tape locations. To make it even simpler, the read/write head can be replaced by a armature that moves from left to right triggering tape locations. We have a very lazy machine! It's name is Olympia. What, then, is the physical activity on which the phenomenal state supervenes? It cannot be in the activity of the armature moving from left to right. That doesn't seem to have the required complexity. Is it in the turning on and off of the tape locations as the armature moves? Again that does not seem to have the required degree of complexity. It might be objected that in stripping out the computational pathway that we did, we have neglected all the other pathways that could have been executed but never in fact were. But what difference do these pathways make? We could construct similar left-right machines for each of these pathways. These machines would be triggered when a counterfactual occurs at a tape location. The triggering mechanism is simple. If, say, t_[3] was originally on just prior to the arrival of the read/write head but is now in fact off, then we can freeze the original machine and arrange for another left-right machine to start from that tape location. This triggering and freezing
Re: Olympia's Beautiful and Profound Mind
Thanks for that very nice summary. I let people think about it. We have discussed it a long time before on the Everything-list. A keyword to find that discussion in the everything list archive is crackpot as Jacques Mallah named the argument. Good we can come back on this, because we didn't conclude our old discussion, and for the new people in the list, as for the for-list people, it is a quite important step to figure out that the UDA is a ``proof, not just an ``argument. Well, at least I think so. Also, thanks to Maudlin taking into account the necessity of the counterfactuals in the notion of computation, and thanks to another (more technical) paper by Hardegree, it is possible to use it to motivate some equivalent but technically different path toward an arithmetical quantum logic. I propose we talk on Hardegree later. But I give the reference of Hardegree for those who are impatient ;) (also, compare to many paper on quantum logic, this one is quite readable, and constitutes perhaps a nice introduction to quantum logic, and I would add, especially for Many-Wordlers. Hardegree shows that the most standard implication connective available in quantum logic is formally (at least) equivalent to a Stalnaker-Lewis notion of counterfactual. It is the David Lewis of plurality of worlds and Counterfactuals. Two books which deserves some room on the shell of For-Lister and Everythingers, imo. Also, I didn't knew but late David Lewis did write a paper on Everett (communicated to me by Adrien Barton). Alas, I have not yet find the time to read it. Hardegree, G. M. (1976). The Conditional in Quantum Logic. In Suppes, P., editor, Logic and Probability in Quantum Mechanics, volume 78 of Synthese Library, pages 55-72. D. Reidel Publishing Company, Dordrecht-Holland. Bruno Le 13-mai-05, à 09:50, Brian Scurfield a écrit : Bruno recently urged me to read up on Tim Maudlin's movie-graph argument against the computational hypothesis. I did so. Here is my version of the argument. According to the computational hypothesis, consciousness supervenes on brain activity and the important level of organization in the brain is its computational structure. So the same consciousness can supervene on two different physical systems provided that they support the same computational structure. For example, we could replace every neuron in your brain with a functionally equivalent silicon chip and you would not notice the difference. Computational structure is an abstract concept. The machine table of a Turing Machine does not specify any physical requirements and different physical implementations of the same machine may not be comparable in terms of the amount of physical activity each must engage in. We might enquire: what is the minimal amount of physical activity that can support a given computation, and, in particular, consciousness? Consider that we have a physical Turing Machine that instantiates the phenomenal state of a conscious observer. To do this, it starts with a prepared tape and runs through a sequence of state changes, writing symbols to the tape, and moving the read-write as it does so. It engages in a lot of physical activity. By assumption, the phenomenal state supervenes on this physical computational activity. Each time we run the machine we will get the same phenomenal state. Let's try to minimise the amount of computational activity that the Turing Machine must engage in. We note that many possible pathways through the machine state table are not used in our particular computation because certain counterfactuals are not true. For example, on the first step, the machine might actually go from S_0 to S_8 because the data location on the tape contained 0. Had the tape contained a 1, it might have gone to S_10, but this doesn't obtain because the 1 was not actually present. So let's unravel the actual computational path taken by the machine when it starts with the prepared tape. Here are the actual machine states and tape locations at each step: S_0 s_8 s_7 s_7 s_3 s_2 . . . s_1023 t_0 t_1 t_2 t_1 t_2 t_3 . . . t_2032 Re-label these as follows: s_[0] s_[1] s_[2] s_[3] s_[4] s_[5] . . .s_[N] t_[0] t_[1] t_[2] t_[3] t_[4] t_[5] . . .t_[N] Note that t_[1] and t_[3] are the same tape location, namely t_1. Similarly, t_[2] and t_[4] are both tape location t_2. These tape locations are multiply-located. The tape locations t_[0], t[1], t[2], ..., can be arranged in physical sequence provided that a mechanism is provided to link the multiply-located locations. Thus t[1] and t[3] might be joined by a circuit that turns both on when a 1 is written and both off when a 0 is written. Now when the machine runs, it has to take account of the remapped tape locations when computing what state to go into next. Nevertheless, the net-effect of all this is that it just runs from left to right. If the machine just runs from left to right, why bother computing the state
Re: Final Announcement
Thank you for telling us, Bruno Le 12-mai-05, à 17:44, Ti Bo a écrit : Final Announcement Data Ecologies 2005 will take place from 9:30 until 16:00 at the Time's Up laboratories in Linz this Friday 13th and Saturday 14th May. Themes include the physics of virtual spaces, whether real space is computed (do we live in a giant computer?) and how to use this for interesting immersive mixed reality spaces. Speakers will be Tom Toffoli Edward Fredkin Juergen Schmidhuber Nik Gaffney Maja Kuzmanovic Daniel Miller Hartwig Thim All the talks will be streamed, so remote participation will be possible and is encouraged. There will be an email address in order to pose questions to the speakers. We look forward to your participation! http://www.timesup.org/laboratory/DataEcologies/ -Tim Boykett TIME'S UP::Research Department \ / Industriezeile 33b A-4020 Linz Austria X+43-732-787804(ph) +43-732-7878043(fx) / \ [EMAIL PROTECTED]http://www.timesup.org - http://www.timesup.org/fieldresearch/setups/index.html http://iridia.ulb.ac.be/~marchal/
Re: Olympia's Beautiful and Profound Mind
We had some discussion of Maudlin's paper on the everything-list in 1999. I summarized the paper at http://www.escribe.com/science/theory/m898.html . Subsequent discussion under the thread title implementation followed up; I will point to my posting at http://www.escribe.com/science/theory/m962.html regarding Bruno's version of Maudlin's result. I suggested a flaw in Maudlin's argument at http://www.escribe.com/science/theory/m1010.html with followup http://www.escribe.com/science/theory/m1015.html . In a nutshell, my point was that Maudlin fails to show that physical supervenience (that is, the principle that whether a system is conscious or not depends solely on the physical activity of the system) is inconsistent with computationalism. What he does show is that you can change the computation implemented by a system without altering it physically (by some definition). But his desired conclusion does not follow logically, because it is possible that the new computation is also conscious. (In fact, I argued that the new computation is very plausibly conscious, but that doesn't even matter, because it is sufficient to consider that it might be, in order to see that Maudlin's argument doesn't go through. To repair his argument it would be necessary to prove that the altered computation is unconscious.) You can follow the thread and date index links off the messages above to see much more discussion of the issue of implementation. Hal Finney
RE: Olympia's Beautiful and Profound Mind
Hal wrote: We had some discussion of Maudlin's paper on the everything-list in 1999. I summarized the paper at http://www.escribe.com/science/theory/m898.html . Subsequent discussion under the thread title implementation followed up; I will point to my posting at http://www.escribe.com/science/theory/m962.html regarding Bruno's version of Maudlin's result. Thanks for those links. I suggested a flaw in Maudlin's argument at http://www.escribe.com/science/theory/m1010.html with followup http://www.escribe.com/science/theory/m1015.html . In a nutshell, my point was that Maudlin fails to show that physical supervenience (that is, the principle that whether a system is conscious or not depends solely on the physical activity of the system) is inconsistent with computationalism. What he does show is that you can change the computation implemented by a system without altering it physically (by some definition). But his desired conclusion does not follow logically, because it is possible that the new computation is also conscious. So the system instantiates two different computations, when all things are considered. The first instantiation is when the counterfactuals are enabled (block removed) and the second instantiation is when the counterfactuals are disabled (block added). Because there are two different computations, we can't conclude that the second instantiation does not lead to a phenomenal state of consciousness. But would you agree though that there does not appear to be sufficient physical activity taking place in the second instantiation to sustain phenomenal awareness? After all, Maudlin went to a lot of trouble to construct a lazy machine! To carry out the second computation, all that needs to happen is that the armature travel from left to right emptying or filling troughs (or, as in my summary, triggering tape locations). It is supposed to be transparently obvious from the lack of activity that if it is conscious then it can't be as a result of physical activity. Now you maintain it is conscious, so wherein lies the consciousness? (In fact, I argued that the new computation is very plausibly conscious, but that doesn't even matter, because it is sufficient to consider that it might be, in order to see that Maudlin's argument doesn't go through. To repair his argument it would be necessary to prove that the altered computation is unconscious.) You can follow the thread and date index links off the messages above to see much more discussion of the issue of implementation. OK, I'm making my way through those. Apologies to the list if the points I raise have been covered previously. Brian Scurfield
RE: Olympia's Beautiful and Profound Mind
Brian Scurfield wrote: Bruno recently urged me to read up on Tim Maudlin's movie-graph argument against the computational hypothesis. I did so. Here is my version of the argument. According to the computational hypothesis, consciousness supervenes on brain activity and the important level of organization in the brain is its computational structure. So the same consciousness can supervene on two different physical systems provided that they support the same computational structure. For example, we could replace every neuron in your brain with a functionally equivalent silicon chip and you would not notice the difference. Computational structure is an abstract concept. The machine table of a Turing Machine does not specify any physical requirements and different physical implementations of the same machine may not be comparable in terms of the amount of physical activity each must engage in. We might enquire: what is the minimal amount of physical activity that can support a given computation, and, in particular, consciousness? Consider that we have a physical Turing Machine that instantiates the phenomenal state of a conscious observer. To do this, it starts with a prepared tape and runs through a sequence of state changes, writing symbols to the tape, and moving the read-write as it does so. It engages in a lot of physical activity. By assumption, the phenomenal state supervenes on this physical computational activity. Each time we run the machine we will get the same phenomenal state. Let's try to minimise the amount of computational activity that the Turing Machine must engage in. We note that many possible pathways through the machine state table are not used in our particular computation because certain counterfactuals are not true. For example, on the first step, the machine might actually go from S_0 to S_8 because the data location on the tape contained 0. Had the tape contained a 1, it might have gone to S_10, but this doesn't obtain because the 1 was not actually present. So let's unravel the actual computational path taken by the machine when it starts with the prepared tape. Here are the actual machine states and tape locations at each step: S_0 s_8 s_7 s_7 s_3 s_2 . . . s_1023 t_0 t_1 t_2 t_1 t_2 t_3 . . . t_2032 Re-label these as follows: s_[0] s_[1] s_[2] s_[3] s_[4] s_[5] . . .s_[N] t_[0] t_[1] t_[2] t_[3] t_[4] t_[5] . . .t_[N] Note that t_[1] and t_[3] are the same tape location, namely t_1. Similarly, t_[2] and t_[4] are both tape location t_2. These tape locations are multiply-located. The tape locations t_[0], t[1], t[2], ..., can be arranged in physical sequence provided that a mechanism is provided to link the multiply-located locations. Thus t[1] and t[3] might be joined by a circuit that turns both on when a 1 is written and both off when a 0 is written. Now when the machine runs, it has to take account of the remapped tape locations when computing what state to go into next. Nevertheless, the net-effect of all this is that it just runs from left to right. If the machine just runs from left to right, why bother computing the state changes? We could just arrange for each tape location to turn on (1 = on) or off (0 = off) when the read/write head arrives. For example, if t_[2] would have been turned on in the original computation, then there would be a local mechanism that turns that location on when the read/write head arrives (note that t_[4] would also turn on because it is linked to t_[2]). The state S_[i] is then defined to occur when the machine is at tape location t_[i] (this machine therefore undergoes as many state changes as the original machine). Now we have a machine that just moves from left to right triggering tape locations. To make it even simpler, the read/write head can be replaced by a armature that moves from left to right triggering tape locations. We have a very lazy machine! It's name is Olympia. The main objection that comes to my mind is that in order to plan ahead of time what number should be in each tape location before the armature begins moving and flipping bits, you need to have already done the computation in the regular way--so Olympia is not really computing anything, it's basically just a playback device for showing us a *recording* of what happened during the original computation. I don't think Olympia contributes anything more to the measure of the observer-moment that was associated with the original computation, any more than playing a movie showing the workings of each neuron in my brain would contribute to the measure of the observer-moment associated with what my brain was doing during that time. What, then, is the physical activity on which the phenomenal state supervenes? It cannot be in the activity of the armature moving from left to right. That doesn't seem to have the required complexity. Is it in the turning on and off of the tape
RE: many worlds theory of immortality
Bruno writes [Lee writes] But many here contend that abstract patterns---mathematical stings, really---can do *so* much cross- referencing and quoting of each other that a form of paste obtains that wields them in to something capable of having experiences. But a familiar abstract object, namely the real numbers between zero and one, evidently already does all of that (considering the decimal or binary expressions), and so I'm not sure what remains for the more abstruse inhabitants of Platonia to do. Such critics can be addressed to any block-universe view of physics, not just mathematical platonia. I believe that the discussions have established that many people have something broader in mind when they use the term block universe. But you could be right: best usage may be as you say. I can't blame the ancients and moderns up to the 19th century for being dualists. It seemed utterly impossible that mere atoms in motion could give rise to such as we. But the painful ---and painstaking---defeat of vitalism achieved finally in the 20th century leaves it the simplest hypothesis by far to say that we are machines. Our souls and we arise by natural means, just as do streams and mountains. Look at my recent posts to the FOR-LIST, which I have cc-send to the everything-list just two minutes ago. Okay, and under the same Subject, I am writing this to both lists. I agree the abandoning of vitalism is progress. And it is true that natural science has explained features like self-reproduction, animal motion, energy transformation (sun - living matter) and so on. But it is just erroneous to conclude that the mind-body problem has been solved. No, it is not just erroneous. I know of many thoughtful people, and include myself as one of them, who believe that the so-called mind body problem is some sort of verbal or linguistic problem. We see it as arising most likely in the minds of people who think there must be a deeper explanation for why highly advanced products of natural selection can report their internal states. And then if we are really digital machine, I offer a case that materialism will be abandoned from purely rational consideration. Matter? A lasting aristotelian superstition ... Well, you could be right! The jury's still out! :-) Observer-moments seems to arise simply from observers, Except that nobody has ever succeed in explaining how the 1-person observer moment can arise from any 3-person description of an observer. And the aforesaid we don't think that anything needs explaining. Almost everyone reading this believes that an AI program could be written such that even if you single-step through it, it will report on its feelings, and that they'll be no less genuine than ours. And from this, I conclude that in all likelihood, there really isn't a problem :-) Lee
