On 10 May 2017 3:04 a.m., "Bruce Kellett" <[email protected]> wrote:
On 10/05/2017 12:41 am, Bruno Marchal wrote: On 09 May 2017, at 09:36, Bruce Kellett wrote: Yes, it does seem that we are each outlining positions and arguments that do not necessarily intersect at many points. I will try and answer some of your more direct questions. Why do I take the view that "the experience of a unique agent such as the one analogised by Hoyle or Barbour would be dominated by random events rather than the order imposed by the predominance of a robust physical-computational mechanism." The reason is that I am starting from a slightly different perspective -- I am looking at the UD as a system in its own right. The questions seem to concern statistics extracted from the behaviour of this system. When approaching such a question, I tend to look on the thermodynamic, or statistical mechanical properties of such a random system. If you take the UD, with its completely random operation over all possible (computer) programs, the analogy that comes to mind is that of thermal equilibrium -- every possible state has equal probability of occurring. Ergodic theory is possible also relevant, but I have less familiarity with that, so tend to stick to ideas deriving from Boltzmann. Given this state of thermal equilibrium, states of some order -- such as conscious moments -- are going to be unlikely, and fluctuations that give single conscious moments are overwhelmingly more likely than more extended fluctuations that give a sequence of related conscious moments. Not sure I understand. The UD is not random at all. The sequence of computational steps may be deterministic, but the net result in the infinite UD is random. Think of Boltzmann's case, a gas of a very large number of molecules. The molecules move and interact according to entirely deterministic laws, but ergodic theory indicates that after a suitable time, the motions of the molecules will be effectively random. I think the same must happen with the dovetailer: although each program is deterministic, the dovetailing of infinitely many such programs means that sequences of individual steps are random (or indistinguishable from random). What is random is the First Person Indeterminacy on all the stable continuations of my states, as seen by the first person, so the first thing to do is to get a mathematical theory of the first person (which I take to Theaetetus, as Gödel's incompleteness makes it work again, again Socrates opinion). Given also the insight from Barbour that each conscious moment -- time capsule -- is self contained, I am not sure that such an intuition is correct. A conscious moment needs at least two universal numbers, but in fine relies on an infinity of them. Nor do I conceive such a thing as an observer moment. the semantic of all first person view (the modalities with "& p" attached to them) are topological. Consciousness is always on an interval, not on a discrete point in some time frame. I was deliberately vague in specifying what was meant by a "conscious moment". I doubt that it is of zero duration, but the duration is indeterminate. Beside, there is no concept of time in the UD, so it is hard to say what a conscious moment might actually be -- some sequence of computational steps, perhaps -- but how many? A time capsule is certainly self-contained. Whether these overlap or not to give a sense of continuity is another question, and would seem merely to extend the notion of a conscious moment in time somewhat -- but what is time? and in itself, a complete explanation of our conscious experience, the computations that pass through our conscious moments are overwhelmingly likely to be random, with just small fluctuations from equilibrium. I.e., single conscious moments with no consistent continuation-- going from white noise to white noise. This is, of course, Russell's Occam catastrophe in a different guise. The experience of the agent is not random -- they experience conscious moments with a seemingly coherent chain of memories giving a comprehensible history -- but there is no reason to suppose that these memories are veridical. They will be more or less plausible, with respect to the normal computations, if they exist of course, but they have to exist if computationalism is correct. The computations underlying the conscious moment have, then, to also compute the physics that renders the memories veridicial -- but that involves memories stretching back tens of years. An awful lot of computations have to come together to make consciousness that means anything. Making the probability in the sea of random noise smaller and smaller all the time. Sure, but probability of what and from whose point of view? Aren't you continuing to think of this principally from a third person perspective (actually merely an abstract "view from nowhere")? Yes, from that impossible point of view there is no conceivable search function that could locate the critical computational structures of this sort; under this interpretation their measure is effectively zero. Nevertheless we know their presence is in fact assured by assumption. In point of fact these computations have the recursive characteristic of exploding into an infinite fractal-like structure of extremely high frequency (as Brent has recently put it) which would give them in a certain and possibly critical sense a highly robust and non-trivial structure. But the key point is that, on the basis of Bruno's theory of computational subjectivity (again, implied by assumption of the CTM), they must be *self-locating* from the first person perspective. This is the key difference that would unleash the creative subjective potential of the torrential output of the UD, as distinct from Borges's merely alphabetical Babel which can only ever be a zero-informational wasteland. But how can we assess "probability" in such a context? Very controversial point as you know. Nonetheless, Hoyle gives us an intuitive heuristic that allows us to think of this in what is effectively a quasi-frequentist manner (i.e. the relative subjective frequency of "encountering" any particular momentary perspective over any finite segment of their abstract serialisation). This heuristic has both absolute (in the first instance) and relativising (in the second) self-sampling characteristics. If we think of it in something like this intuitive way (which IMO is the absolute key to the argument) then the justification of a measure assessed in the above manner has to lie in the direction of understanding how and why the "organised" threads of narrative subjectivity shouldn't be effectively swamped in a sea of subjective chaos because of competition from "pathological" quasi-narrative fragments. I've tried to pump our collective intuition with various analogies to suggest why this wouldn't necessarily be the case, to supplement Bruno's more rigorous logico-mathematical argument. Hardly conclusive of course but the intention is principally to encourage a harder look in this direction. The sea of pathological dross that must form the overwhelming but fragmented majority of the "conscious potential" of UD* must somehow be effectively suppressed from the perspective of the relatively tiny, but mightily persistent and powerful narrative threads of veridical consciousness (i.e. those that refer truthfully to an externality that in turn explicates their perceptions of it, or what we call physics). A pathway of least effort through the phase space of possible subjectivity? Russell's solution to the possibility of an Occam catastrophe that would sink this fragile vessel is simply to assume that this physics is the unique requirement for its own observation. Open problem, as Bruno would say? David So there is no order imposed by the computational mechanism. All computation are ordered structure, ordered by the universal numbers which implement them. But indeed, the first person duration is not directly ordered by this or that universal numbers, but by all those who operate the computations which exists below my substitution level. Which probably involves the whole universe, from the big bang to the eventual heat death -- else memories are not veridical. The statistics over these conscious moments does not give rise to any consistent physics. I say that "physics has to have an independent existence" because the failure of the attempt to extract physics from the UD means that the only way one can connect these independent 'conscious moments' is if they are, following Barbour, points in an independently existing configurations space. Barbour calls this "Platonia", within which physics is defined, but this is far from the platonia of arithmetical realism. The upshot is that physics does not come from the UD, but from somewhere else -- that elsewhere not necessarily clearly specified at this point. Since the reversal, or the extraction of physics, seems to me to be the weak point of Bruno's argument, Well, the goal of the UDA is just to transform the mind-body problem into a body problem in arithmetic. Then what is weak in the AUDA, the math part, is that nobody seems to be interested in solving the open problems, but that is contingent. I am not sure you can say that it is weak. It is only unfinished, but the complexity comes from the difficulty of the subject, which is naturally reflected in the open problems? To find quantum logic where it is needed is on the contrary a good sign that we might extract the full measure, then works à-la-Hardy or Russell's, can be used to progress. it is right that we should spend more time looking at alternative interpretations of the UDA. UDA is a argument, as such it does not admit any interpretation. It is valid, or non valid. I guess you mean to search an alternative to mechanism. Not really at this stage -- just an alternative understanding of the dovetailer. Bruce This, I would understand if the material hypostases would have collapsed into classical logic, or would be strongly opposed to quantum logic, but without evidence for non mechanism, I am not sure if it is not premature to abandon mechanism , given that mechanism already give a quantum logic. To abandon computationalism at this stage, before testing the logic of the observable that we already have, seems weird to me. Bruno -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
