RE: Many Pasts? Not according to QM...
Lee Corbin writes: Stathis writes ...I think we may basically agree, but there are some differences. If you look at it from a third person perspective, continuity of personal identity over time is not only a delusion but a rather strange and inconsistent delusion. I'm not quite sure I understand why you say this. Do you only mean that *continuity* can be manipulated, e.g., on the one hand we suffer a discontinuity every night when we fall asleep; on the other, in the future it will be possible to record your Monday experience, your Tuesday experience, etc., and then a few months later play them back in reverse sequence? (We might even give the latter replays tremendous measure, so that so far as the parameter *time* is concerned, almost all of your Mondays occurred after your Wednesdays. Or do you mean more? The OM's are straightforward empirical observation: I'm now having the experience of typing this sentence. How this experience comes about, whether there really is a physical keyboard in front of me, and so on, may be in question, but not the fact that I am having the experience. Stringing the OM's together to construct an individual who persists through time, however, is not straightforward: I believe that tomorrow I will become one of the people in the multiverse who believe they are me and share my memories. When I think about this, I hope that my future selves will have good experiences, and I fear that they might have bad experiences. Once tomorrow comes, I no longer care about the other versions, because they aren't me even though they think they are me. Looking back, also, I believe that I was only one of the possible versions in the multiverse, and I no longer care about bad experiences that person might have had in the same way that I care about bad experiences I am having at present or one of the versions of me might have in the future. We normally take all this for granted, but if you think about it, it is quite arbitrary. Why should I believe I will become another person who thinks he is me? Why should I identify with multiple versions of me in the future, but not the present or the past? Why should I worry about what might happen to my future self but not my past self? The answer is, because that is the way human minds have evolved. But that is the only reason. It would be no logical contradiction to imagine a person whose mind functioned very differently; for example, a person who had no fear of the future because he considered the idea absurd that he could become someone with different spacetime coordinates to his present ones. It is the failure to take into account this rather complex scheme we use to create individuals that leads to mistakes in the application of OM measure, for example in criticising the QTI. I still feel that there is a 10% chance I will be tortured, and I still feel relieved that I am one of the lucky copies when tomorrow comes and I am not tortured. There is an inconsistency here in that today I identify with all the copies and tomorrow I identify with only one, but so what? As you say, that is how our minds have evolved. Yes. If the experiences of the copy who is to be tortured will eventually be merged with those of the non-tortured copies, that changes the situation, because then it is *guaranteed* that I will eventually experience the torture. Good point. To be precise let's say that tomorrow you will split into the ten copies, one of which will be tortured. Then one *year* from now merging is scheduled to occur. Therefore you behave differently? I don't think you should. (You may *have* to because that's how we are built, but you still shouldn't.) Given this information before the split occurs, it makes it more likely that I will experience torture: the 1/10 chance initially, then the certainty of merging in a year - although the merging may result in memory of the torture rather than the first hand experience. As I like to say just because you are not (locally) experiencing something, doesn't mean it isn't happening to you. Suppose that you don't know whether any merging is to ever happen. How should that change the way you feel about your copy being tortured? Now, I grant that you don't get the sweaty palms if there won't be any merging, but to me that's just a base animalistic reflex action. The truth is that *you* are in two places at the same time, and in the other place you are hurting a lot. The point is that *now* your duplicate is in pain. For purely selfish reasons, this should be a big deal to you, I contend. Whether or not eons from now some merging does or does not take place shouldn't change your approval or disapproval of physical events taking place now. I have to disagree with you here. Why should I care about the suffering of some guy in another universe who thinks he is me, and whom I can never meet? I would be more concerned about the suffering of strangers
RE: Equivalence
Sorry, but I don't have much of an idea of what is being discussed
in this thread. Could you try to enlighten me?
Rmiller originally wrote
Equivalence
If the individual exists simultaneously across a many-world manifold, then
how can one even define a copy?
Well, I would say this (i.e., those words mean the following to me):
Are you asking what the *meaning* of copy is in this context? That is,
are you suggesting that from a physics standpoint, if we have two
identical (or nearly identical) quantum states at different points
of the multiverse, then how can *one* of them be picked out as a
copy of the *other*? I agree it seems reflexive; that is, if A is
a copy of B, then B is a copy of A. But I don't see the significance
of where this is leading.
1. An *exact* copy (which I think you are talking about) could in
principle be obtained from a machine that made an exact molecular
replicant of one. Let us further stipulate that one's *exact*
environment (say out to a few light-seconds) is also duplicated.
Then the person has two copies both having identical experiences.
In fact, I would use this to help *define* what is meant by existing
simultaneously across a many-world manifold.
If the words match at some points and differ at others, then the
personality would at a maximum, do likewise---though this is not
necessary---or, for some perhaps, not even likely.
What? What do you mean by the words match? Do you mean that if
each copy happens to be speaking?
It's been long established that the inner world we navigate is an
abstraction of the real thing---even if the real world only consists of
one version. If it consists of several versions, blended into one another,
then how can we differentiate between them?
By the inner world being an abstraction of the real thing, I guess
that you mean our perception of 3 space around us is not an identical
map of the 3 space around us. Is that right? But how could the
real world be one version? Or do you mean one instance from a set
of identical versions?
From a mathematical POV, 200
worlds that are absolute copies of themselves, are equivalent to one world.
Yes, it is a convention of set theory that the set {1, 2, 3, 1, 4, 5}
really has only five elements, not six. But a good number of us here
suppose that just as in probability and measure theory, a single point
can be associated with either a high or low probability.
But one is free to observe, say, N electrons all in the same state. We
persist in regarding these as separate electrons, and I don't think
that there is anything wrong with that. It does depend on how you look
at it (is there only one electron in the universe? Feynman and Wheeler
suppose that there was in one paper).
If these worlds differ minutely in areas *not encountered or interacted
with by the percipient (individual), then again we have one percipient, one
world-equivalent...
I just couldn't follow any more of what you are saying.
Thanks for any clarification,
Lee
RE: Functionalism and People as Programs
R. Miller writes Lee Corbin wrote: Stephen writes I really do not want to be a stick-in-the-mud here, but what do we base the idea that copies could exist upon? It is a conjecture called functionalism (or one of its close variants). Functionalism, at least, in the social sciences refers to the proposition that everything exists because it has a function (use). Well, that is *not* at all the meaning of the term in philosophy. To put it simply, if it behaves like a duck in every particular, it is a duck. I notice that many people seek refuge in the no-copying theorem of QM. Well, for them, I have that automobile travel also precludes survival. I can prove that to enter an automobile, drive it somewhere, and then exit the automobile invariably changes the quantum state of the person so reckless as to do it. If someone can teleport me back and forth from work to home, I'll be happy to go along even if 1 atom in every thousand cells of mine doesn't get copied. Exposure to a nuclear detonation at 4000 yds typically kills about 1 in a million cells. When that happens, you die. I would suggest that is a bad metaphor. Well, my numbers, above, are *entirely* different from yours. One in a million cells is a *terrible* loss. But one atom? There are 10^14 atoms per cell. (And 10^14 cells in a typical human.) I would stick with my numbers. But in case you are somehow right, and that each cell would be wrecked by the loss of a single atom, my point can be made by relaxing the numbers: replace what I've written by I'll be happy to teleport even if 100 trillion atoms are destroyed: a whole cell, gone. Lee P.S. Thanks for the interesting fact that death of 1/10^6 cells kills one.
RE: Functionalism and People as Programs
At 12:36 PM 6/4/2005, Lee Corbin wrote: R. Miller writes Lee Corbin wrote: Exposure to a nuclear detonation at 4000 yds typically kills about 1 in a million cells. When that happens, you die. I would suggest that is a bad metaphor. Well, my numbers, above, are *entirely* different from yours. One in a million cells is a *terrible* loss. But one atom? There are 10^14 atoms per cell. (And 10^14 cells in a typical human.) I would stick with my numbers. But in case you are somehow right, and that each cell would be wrecked by the loss of a single atom, my point can be made by relaxing the numbers: replace what I've written by I'll be happy to teleport even if 100 trillion atoms are destroyed: a whole cell, gone. Lee, As I indicated earlier, I was out to lunch on that one-in-a-million cells/atoms deal. As I understand it, one cell killed out of a million is lethal, however. R.
Existence of Copies (was RE: Functionalism and People as Programs)
Stephen writes Stephen writes I really do not want to be a stick-in-the-mud here, but what do we base the idea that copies could exist upon? Don't worry about not going along with someone's program ;-) I think that you're just being polite by calling yourself a stick-in-the-mud. Why, if I had to interpose such a disclaimer every time that I was stubborn and mule-headed, 90% of my posts would be consist of nothing but apologies!! :-) To prevent most of us from feeling inadquate, you should suppress some of your southern politeness in these discussions :-) It is a conjecture called functionalism (or one of its close variants). I guess the strong AI view is that the mind can be emulated on a computer. And yes, just because many people believe this---not surprisingly many computer scientists---does not [necessarily] make it true. [though I myself (Lee and his copies) believe it] [SPK] I am aware of those ideas and they seem, at least to me, to be supported by an article of Faith and not any kind of empirical evidence. Maybe that is why I have such an allergy to the conjecture. ;-) Well for Pete's sake! Of *course* there is some faith here---as you wryly note, you yourself are hardly exempt from indulging in a little (or a lot) of speculation. What you have written is not even an argument. Whereas what Brent Meeker wrote I think there is considerable evidence to support the view that human level intelligence could be achieved by a (non-quantum) computer and that human intelligence and consciousness are dependent on brain processes; e.g. see the many studies of brain damaged patients. Also, I think it is well established that consciousness corresponds to only a small part of the information processing in the brain. definitely constitutes a strong argument, even if from your point of view it does not constitute evidence. (Thanks, Brent!) [LC] An aspect of this belief is that a robot could act indistinguishably from humans. At first glance, this seems plausible enough; certainly many early 20th century SF writers thought it reasonable. Even Searle concedes that such a robot could at least appear intelligent and thoughtful to Chinese speakers. I suspect that Turing also believed it: after all, he proposed that a program one day behave indistinguishably from humans. And why not, exactly? After all, the robot undertakes actions, performs calculations, has internal states, and should be able to execute a repertoire as fine as that of any human. Unless there is some devastating reason to the contrary. [SPK] What I seem to rest my skepticism upon is the fact that in all of these considerations there remains, tacitly or not, the assumption that these internal states have an entity to whom they have a particular valuation. This is the central problem from those who are deeply concerned as to *why* 1st person experiences exist. Too bad that to me, it's just obvious that they must. I literally cannot conceive of how it could be different! (Poor me, I suppose---in some ways some of us just have too little imagination, I truly guess.) I see this expressed in the MWI, more precisely, in the relative state way of thinking within an overall QM multiverse. Okay; On closer reading, I think that you are talking about the way that many people cannot stand MWI because it seems to require that they observe both outcomes of an experiment. Additionally, we are still embroiled in debate over the sufficiency of a Turing Test to give us reasonable certainty to claim that we can reduce 1st person aspects from 3rd person, Searle's Chinese Room being one example. What if I, or any one else's 1st person aspect, can not be copied? If the operation of copying is impossible, what is the status of all of these thought experiments? I notice that many people seek refuge in the no-copying theorem of QM. Well, for them, I have that automobile travel also precludes survival. I can prove that to enter an automobile, drive it somewhere, and then exit the automobile invariably changes the quantum state of the person so reckless as to do it. [SPK] Come on, Lee, your trying to evade the argument. ;-) Am not! If the shoe doesn't fit, then don't wear it. I thought (mistakenly, it appears) that you were seeking refuge in the no-clone QM theorem. Sorry for the misattribution. What you are saying---PLEASE CORRECT ME IF I AM WRONG---is that copying just might not be possible at all. But I don't understand! Surely you admit that it is conceivable that a machine might scan your brain and body and create a duplicate. (As I say, it doesn't have to be **exact**.) But didn't you see it happen many times on Star Trek? Or were you in the other room (as I often was) visiting the refrigerator? Is this or is this not what you mean by suppose that copying is impossible?
When and How Unconscious Processes Matter
Brent wrote -Original Message- From: Brent Meeker [mailto:[EMAIL PROTECTED] Sent: Friday, June 03, 2005 8:39 AM To: Everything-List Subject: RE: Functionalism and People as Programs I think there is considerable evidence to support the view that human level intelligence could be achieved by a (non-quantum) computer and that human intelligence and consciousness are dependent on brain processes; e.g. see the many studies of brain damaged patients. Also, I think it is well established that consciousness corresponds to only a small part of the information processing in the brain. Yes. That's something that bothers me about the discussion of observer moments with the implication that only the conscious observation matters. That's an interesting point. I could retort that if it's unconscious, then it doesn't matter. But that sounds too facile. That is, how do I know that the quality of life is really the same were (over any moment) my unconscious processes omitted? Now, firstly, one is sort of aware of certain unconscious processes. For example, a moment later, you may become aware that you were tapping your foot. What would you say about us substituting conscious and unconscious experience for conscious experience in our discussions OMs? That would be fine with me. It would allow us to bypass your point and continue to address what we were talking about. But I do feel that perhaps you are onto something here that maybe should not be bypassed. Lee
RE: Observer-Moment Measure from Universe Measure
Hal Finney has provided some intriguing notions and possibly some very useful explanations. But I would like help in clarifying even the first several paragraphs, in order to maximize my investment in the remainder. But first a few comments; these may be premature, but if so, the comments should be ignored. Some time back Lee Corbin posed the question of which was more fundamental: observer-moments or universes? I would say, with more thought, that observer-moments are more fundamental in terms of explaining the subjective appearance of what we see, and what we can expect. But in general, what do observer-moments explain? Or what does the hypothesis concerning them explain? I just don't get a good feel that there are any higher level phenomena which might be reduced to observer-moments (I am still very skeptical that all of physics or math or something could be reduced to them---but if that is what is meant, I stand corrected). Rather, it always seems like a number of (other) people are trying to explain observer-moments as arising from the activity of a Universal Dovetailer, or a Platonic ensemble of bit strings, or something. An observer-moment is really all we have as our primary experience of the world. The world around us may be fake; we may be in the Matrix or a brain in a vat. Even our memories may be fake. But the fact that we are having particular experiences at a particular moment cannot be faked. Nothing could be truer. But the universe is fundamental, in my view, in terms of the ontology, the physical reality of the world. Universes create and contain observers who experience observer-moments. This is the Schmidhuber/Tegmark model... Yes, but now arises my need for clarification: In terms of measure, Schmidhuber (and possibly Tegmark) provides a means to estimate the measure of a universe. Consider the fraction of all bit strings that create that universe as its measure. I think that perhaps I know exactly what is meant; but I'm unwilling to take the chance. Let's say that we have a universe U, and now we want to find its measure (its share of the mega-multi-Everything resources). So, as you write, we consider all the bit strings that create U. Let's say for concreteness that only five bit strings really exist in some deep sense: 010101110100101010011101010110001010110101... 10110111010001010111001011010110100101... 0010101001110101001110100010011010... 1101110100010011010l11011101010011... 1100101110101011101000110100101001... and then it just so happens that only 2 out of these five actually make the universe U manifest. That is, in the innards of 2 of these, one finds all the structures that U contains. Am I following so far? In practice this is roughly 1/2^n where n is the size of the shortest program that outputs that universe. So each of these universes (each of the five, in my toy example) has a certain Kolmogorov complexity? Each of the five can be output by some program? But is that program infinite or finite? Argument for finite: normally we want to speak of *short* programs and so that seems to indicate the program has a limited size. Argument for infinite: dramatically *few* bit strings that are infinite in length have just a finite amount of information. Our infinite level-one Tegmark universe, for example, probably is tiled by Hubble volumes in a non-repeating irregular way so that no program could output it. Thanks, Lee The Tegmark model may allow for similar reasoning, applied to mathematical structures rather than computer programs. Now, how to get from universe measure to observer-moment (OM) measure? This is what I want to write about
Hypothetical shaman's dilemma
Here's a hypothetical situation. Your plane goes down in the wilds and you're rescued by a tribe indigenous to the area. You're wearing the latest clothes from the GAP, so the tribe elders decide you're a candidate for shaman apprentice--a position that comes with nice lodging and pays well indeed. The chief shaman likes you and decides to let you in on a secret: shamans exploit a brand of multiverse QM theory in that they do their magic by scanning various future branches of the tribe's world line in order to predict what will take place (rain, good weather, winning tickets at the lottery, etc.) Getting the branch right is a bit difficult, but with practice one can get within a few worlds of the path on the world line the tribe eventually takes. You discover that each branch is very deterministic and causal-based---and once on a path, one thing reliably leads to another. You discover that your job as shaman is to keep everyone's attention, and once you've done that, to direct them down a reliable path. You decide it's not too different from the corporate world, so you're eager to have a go at it. You learn quickly and after a month or so, you can generally intuit (no pun intended) what the possibilities (paths) are for the tribe, and you're able to steer them as a unit down that path. With that, the shaman retires and you take his place. Then, the chief takes ill. You saw it coming but you thought it would be on another path---but you were wrong. Now you look ahead and all the paths forward are deterministic and end with the death of the chief. But, the tribe is relying on you to make the chief well. So you go to the retired shaman and ask him what to do. He replies that you *can't* make the chief well---especially if all the paths forward are deterministic and all end in death for the chief. But as a shaman there are things you can do that will shake things up that will result in placing the entire tribe---and you included---on a completely new track---that might save the chief's life. The downside: both you and tribe will be on an entirely different path--determined by completely unknown histories. You might save the chief's life, but on that new path, an errant virus (from a different history) could hit the tribe, wiping it out. Worse, to save the chief's life, you as a shaman would (for a few weeks or months) have no access to the future. By performing a miracle you'd be placing the entire tribe--as well as yourself--onto a completely different path, with different histories and thus different rules (though the history would *seem* the same). Would you take the chance and shake things up? Or would you keep the tribe on the familiar world line and end up losing the chief (and everyone's confidence.) RM
RE: Observer-Moment Measure from Universe Measure
Lee Corbin writes: But in general, what do observer-moments explain? Or what does the hypothesis concerning them explain? I just don't get a good feel that there are any higher level phenomena which might be reduced to observer-moments (I am still very skeptical that all of physics or math or something could be reduced to them---but if that is what is meant, I stand corrected). Rather, it always seems like a number of (other) people are trying to explain observer-moments as arising from the activity of a Universal Dovetailer, or a Platonic ensemble of bit strings, or something. I would say that observer-moments are what need explaining, rather than things that do the explaining. Or you could say that in a sense they explain our experiences, although I think of them more as *being* our experiences, moment by moment. As we agreed: An observer-moment is really all we have as our primary experience of the world. The world around us may be fake; we may be in the Matrix or a brain in a vat. Even our memories may be fake. But the fact that we are having particular experiences at a particular moment cannot be faked. Nothing could be truer. That is the sense in which I say that observer-moments are primary; they are the most fundamental experience we have of the world. Everything else is only a theory which is built upon the raw existence of observer-moments. In terms of measure, Schmidhuber (and possibly Tegmark) provides a means to estimate the measure of a universe. Consider the fraction of all bit strings that create that universe as its measure. I think that perhaps I know exactly what is meant; but I'm unwilling to take the chance. Let's say that we have a universe U, and now we want to find its measure (its share of the mega-multi-Everything resources). So, as you write, we consider all the bit strings that create U. Let's say for concreteness that only five bit strings really exist in some deep sense: 010101110100101010011101010110001010110101... 10110111010001010111001011010110100101... 0010101001110101001110100010011010... 1101110100010011010l11011101010011... 1100101110101011101000110100101001... and then it just so happens that only 2 out of these five actually make the universe U manifest. That is, in the innards of 2 of these, one finds all the structures that U contains. Am I following so far? In the Schmidhuber picture, it's not that the strings contain U, rather the strings are programs which when run on some UTM produce U as the output. This corresponds to the concept you mention below, the Kolmogorov complexity. KC is based on the length of programs that output the objects (strings, or universes, or any other information based entity). Measure as I am using it is 1/2^KC where KC is the Kolmogorov complexity of an object. In practice this is roughly 1/2^n where n is the size of the shortest program that outputs that universe. So each of these universes (each of the five, in my toy example) has a certain Kolmogorov complexity? Each of the five can be output by some program? Yes, I think this is equivalent to my conception, although when I spoke of bit strings I was thinking of the inputs to the UTM while you are talking about the outputs. But the basic idea is the same. But is that program infinite or finite? Argument for finite: normally we want to speak of *short* programs and so that seems to indicate the program has a limited size. Argument for infinite: dramatically *few* bit strings that are infinite in length have just a finite amount of information. Our infinite level-one Tegmark universe, for example, probably is tiled by Hubble volumes in a non-repeating irregular way so that no program could output it. Now I think we are both talking about the inputs to the UTM. Should we consider infinite length inputs? I don't think it is necessary, for three reasons. First, due to the way TM's work, in practice a random tape will only have some specific number of input bits that ever get used. The chance of an infinite number of bits being used is zero. Second, you could construct tapes which used an infinite number of bits, but they would be of measure zero and hence would make no detectable contribution to the actual numeric predictions of the theory. Third, there are variants on UTMs which only accept self-delimiting input tapes that have, in effect, lengths that are easily determined. Greg Chaitin's work focuses on the use of self-delimiting programs to achieve a more precise picture of algorithmic complexity (which is equivalent to KC). The lengths of such programs are inherently finite. These UTMs are equivalent to all others. Note that you could, I think, create an infinite universe even using a finite tape. I believe that our universe, even if infinite in Tegmark's level-one sense, could be output by a finite program, at least in an MWI model. The amount of
