Pity then Bruce,
We humans could use the company and maybe the advice. -----Original Message----- From: Bruce Kellett <[email protected]> To: everything-list <[email protected]> Sent: Mon, May 8, 2017 1:01 am Subject: Re: What are atheists for? On 8/05/2017 2:45 pm, spudboy100 via Everything List wrote: Rather than use the Boltzmann Brain hypothesis to elucidate the conservation of energy in thermodynamics and entropy, why not take Boltzmann a bit more seriously, and search for these suckers in the galaxy, in other words, treat, as a working hypothesis BB's as real phenomena? There's nobody out there that is sending easy to listen to, signals. Maybe the BB's are probing people's butts as a prank, by pretending they are UFO's? Hardee Har Har! I think that, given a physical universe, Boltzmann brains are highly unlikely. The reasons are essentially those elucidated by Sean Carroll, http://arxiv.org/abs/1405.0298v1 . Namely de Sitter space is a quiescent vacuum in which there are no quantum fluctuations of the sort hypothesized to give rise to Boltzmann brains. The problem is that David (and Bruno) cannot appeal to such an argument, because Carroll presupposes a physical universe, and they can't do that on pain of circularity. Bruce In fact, just as Boltzmann realized in the Boltzmann brain problem, states of complete randomness both before and after our current conscious moment are overwhelmingly more likley than that our present moment is immersed in a physics that involves exceptionless conservation laws, so that the past and future can both be evolved from our present state by the application of persistent and pervasive physical laws. -----Original Message----- From: Bruce Kellett <[email protected]> To: everything-list <[email protected]> Sent: Sun, May 7, 2017 11:53 pm Subject: Re: What are atheists for? On 8/05/2017 3:14 am, David Nyman wrote: On 6 May 2017 11:04 p.m., "Brent Meeker" <[email protected]> wrote: On 5/6/2017 2:45 PM, David Nyman wrote: On 6 May 2017 10:16 p.m., "Brent Meeker" <[email protected]> wrote: But that's what I mean when I say Bruno's theory has no predictive success. QM (and Everett) would correctly predict that alcohol molecules in the blood will interfere with neuronal function and THEN invoking the physicalist theory of mind, i.e. that mind supervenes on material events, it predicts that your ability to do arithmetic will be impaired by drinking tequila. It will NOT predict the contrary with more than infinitesimal probability. So it's misdirection to say that it's just a measure problem. Without having the right measure a probabilistic theory is just fantasy...or magic as Bruno would say. I have no idea why you say that. I thought it was clear that if computationalism doesn't (ultimately) predict that its predominating computational mechanism (i.e. the one effectively self-selected by complex subjects, in this case, like ourselves) is the physics those selfsame subjects observe, That would certainly be an accomplishment - which in another post Bruno says is trivially accomplished even in RA (I don't see it). But to succeed in prediction it is not enough to show that some world exists in which mind and physics are consistent (that the physics that mind infers is also the real physics that predicts effects on the mind). You need also to show this has large measure relative to contrary worlds. One can make a logic chopping argument that it must be that way for otherwise minds would not be making sense of the physics they perceived - but that makes the whole computational argument otiose. I've been thinking a bit more about this and I'd like to set out some further tentative remarks about the above. Your professional expertise in these matters is orders of magnitude greater than mine and consequently any comments you might make would be very helpful. By the way, it would also be helpful if you would read beyond the next paragraph before commenting because I hope I will come by myself to the fly in the ointment. Firstly, and "assuming computationalism" on the basis of CT + YD, we are led to the view that UD* must include all possible "physical" computational continuations (actually infinitely reiterated). This of course is also to assume that all such continuations are finitely computable (i.e. halting). Now, again on the same assumptions, it might seem reasonable that our observing such a physics in concrete substantial form is evidence of its emergence (i.e. epistemologically) as the predominant computational mechanism underlying those very perceptions. Hence it might seem equally reasonable to conclude that this is the reason that these latter correspondingly appear to supervene on concrete physical manifestations in their effective environment. Now wait a minute. We cannot escape the question of measure. Why would it be reasonable to assume that a physics of this sort should predominate in the manner outlined above? Well, firstly, it would seem that the generator of the set of possible physical computations is infinitely reiterative​ and hence very robust (both in the sense of computational inclusiveness a la step 7, and that of internal self-consistency). But who is to say that the generators of "magical" or simply inconsistent continuations aren't equally or even more prevalent? After all we're dealing with a Library of Babel here and the Vast majority of any such library is bound to be gibberish. Well, I'm wondering​ about an analogy with Feynman's path integral idea (comments particularly appreciated here). Might a kind of least action principle be applicable here, such that internally consistent computations self-reinforce, whereas inconsistent ones in effect self-cancel? Also, absence of evidence isn't evidence of absence. I'm thinking here about the evaluation of what we typically remember having experienced. I can't help invoking Hoyle here again (sorry). Subjectively speaking, there's a kind of struggle always in process between remembering and forgetting. So on the basis suggested above, and from the abstract point of view of Hoyle's singular agent (or equally Bruno's virgin machine), inconsistent paths might plausibly tend to result, in effect, in a net (unintelligible) forgetting and contrariwise, self-consistent paths might equally plausibly result in a net (intelligible) remembering. I'm speaking of consistent and hence intelligible "personal histories" here. But perhaps you would substitute "implausibly" above. Anyway, your comments as ever particularly appreciated. I think the problem here is the use of the word "consistent". You refer to "internally consistent computations" and "consistent and hence intelligible 'personal histories'." But what is the measure of such consistency? You cannot use the idea of 'consistent according to some physical laws', because it is those laws that you are supposedly deriving -- they cannot form part of the derivation. I don't think any notion of logical consistency can fill the bill here. It is logically consistent that my present conscious moment, with its rich record of memories of a physical world, stretching back to childhood, is all an illusion of the momentary point in a computational history: the continuation of this computation back into the past, and forward into the future, could be just white noise! That is not logically inconsistent, or comutationally inconsistent. It is inconsistent only with the physical laws of conservation and persistence. But at this point, you do not have such laws! In fact, just as Boltzmann realized in the Boltzmann brain problem, states of complete randomness both before and after our current conscious moment are overwhelmingly more likley than that our present moment is immersed in a physics that involves exceptionless conservation laws, so that the past and future can both be evolved from our present state by the application of persistent and pervasive physical laws. Unless you can give some meaning to the concept of "consistent" that does not just beg the question, then I think Boltzmann's problem will destroy your search for some 'measure' that makes our experience of physical laws (any physical laws, not just those we actually observe) overwhelmingly likely. Bruce -- 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. -- 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.
