On 15 July 2017 at 03:22, Bruce Kellett <[email protected]> wrote:
> On 15/07/2017 10:34 am, David Nyman wrote: > > On 15 July 2017 at 00:46, Bruce Kellett < <[email protected]> > [email protected]> wrote: > >> >> On 15/07/2017 4:00 am, David Nyman wrote: >> >> ISTM, on reflection, that my tentative suggestion that the alternative >> cases are in some deeper sense 'unphysical' have some sort of explanatory >> force. It's circular of course, but not I think in a vicious way. IOW it >> would be the case that there just were no well-formed physical >> circumstances in which such encounters could occur. >> >> >> Well yes, that is what the singlet state means -- there are no physical >> circumstances in which the branches that form could violate QM. But that is >> a statement of the fact, not an explanation of that fact. >> > > Well, it's at least pointing in the direction of a mode of explanation > in terms of a tight constraint on what could count as viably physical. > Others have noted that physics (at least a physics adequate to support our > kind of observer-hood) is suspiciously replete with such tight constraints. > As I said, this would be a mystery if regarded merely as a brute given > (i.e. it could simply have been otherwise) and hence it tends to point in > the direction of a constraint on observational selection from a more > general basis. And if so, it would of course then be the case that only > appropriately-constrained phenomena, arising from such states of affairs as > were physically capable of supporting observation, would thereby be > observable. > > > I think that this is looking at it in the wrong way. Things can look very > constrained and unnatural if you reverse the direction of explanation. If > you take the physical world, with all its complexity, as the starting > point, and then understand human consciousness as having evolved in this > environment, then there is no real mystery to be explained. > I'm not sure I follow your logic here. The point I was making is that "the physical world, with all its complexity" looks highly constrained, something that is indeed widely noted - a put up job, to quote Fred Hoyle. It has further been noted that such tightness of constraint might point to its being a prerequisite for sentient life and hence for the conditions of observation itself. Consequently, far from looking "very constrained and unnatural if you reverse the direction of explanation", it's the opposite that seems increasingly possible. IOW, things look less constrained and unnatural if you take the view that the observed conditions are observationally selected from a more generalised basis. As to mysteries, take your pick. The one to which I was referring was treating the complex physical world to which observation gives access as a brute given. Of course this is a viable metaphysical position at which to stop further enquiry. However, there remain motivations to look for a more general basis from which such complexity might be derived, such as those we are presently discussing. Such efforts cannot ultimately resolve the mystery, of course, but they can perhaps simplify it. > > >> ISTM however that any such notion implies a deeper level from which QM as >> we observe it gets 'selected' on what is essentially an anthropic (hate >> that term) basis. >> >> >> If you want to go down this route you still have to give an account of >> how this selection might come about -- why is it that violations of QM are >> fatal to consciousness? >> > > They would be fatal to consciousness if such violations precluded the > formation of physical states of affairs adequate to comprise the vehicles > of that consciousness and the environments on which their consistent > experiences depended (as Brent has often noted). > > > I think Brent has commented that consciousness needs a world to be > conscious of -- that doesn't, of itself, constrain that world in any way. > I am speaking here of our actual experience, not some hypothetical alternative. Consequently 'our' world is constrained to exhibit just those phenomena that we actually observe and that support our physical existence and that of our environment, and no others. > Even more so if the consciousness is a product of evolution in that world. > Evolution cannot produce anything that contradicts the laws of physics. > My point precisely. We may also hope and trust that it hasn't produced in us an intelligence that is condemned to be hopelessly deluded by its scientific investigation of the nature of its physical environment. > > > >> This in turn would imply that an entangled QM-physics is a prerequisite >> for (at least our species of) observation itself.Of course, if we >> hypothesise, on the basis of a computational theory of mind, that QM is >> indeed observationally selected from a deeper arithmetical level, then a >> 'canonical' physics of precisely this kind is indeed implied. In this >> scenario, computational continuations implying non-entangled encounters >> simply don't correspond to any of the observable 'physical worlds'. >> >> >> I have raised problems with the idea that consciousness "selects" >> specifically quantum behaviour in another thread. The basis of my worry >> with this is that there does not seem to be anything to rule out a purely >> Newtonian classical world exhibiting consciousness as we know it -- that is >> implied by substrate independence, strong AI, and the assumed ability to >> replace our consciousness with the equivalent computations carried out on a >> classical Turing machine. Hence quantum mechanics is not entailed by >> consciousness, so it is difficult to see how consciousness could select out >> specific facts about the world that were inconsistent with QM. >> > > But surely the counter-argument to that is that a truly Newtonian > classical world wouldn't in fact be a viable physical world at all? For > example, the Newtonian 'atom' would collapse more or less instantaneously. > > > A Newtonian classical world would not be our world explained in terms of > purely Newtonian physics: it would be a world in which everything was > explained by Newtonian and Maxwellian physics. So atoms would be solid > entities interacting according to some force law -- not Rutherford atoms > with a nucleus and surrounding electrons; stability questions would not > arise. This world would be quite different from ours in many respects -- > basically, as non-quantum, there would be no quantum effects. But Turing > machines do not rely on quantum effects, so they could exist, and support > consciousness, in such a world. > The point here is not whether Turing machines are classical in themselves, which is of course accepted. The point is rather what kind of worlds would appear in the observational spectra of such machines. And what is therefore at issue is whether, assuming QM-type phenomena are a prerequisite for our particular species of observer-hood, such phenomena do indeed fall within the spectra of such machines, in the limit argued for in the UDA. As I have remarked above, it is entirely reasonable to suppose, on the argument of tightness of constraints, that such phenomena are indeed a prerequisite rather than some baroque, optional feature of the world we happen to observe. Consequently, a Newtonian/Maxwellian world such as you posit might indeed be 'observable' by some collection of TMs, just not those that happen to be implicated in our own experience. > > > > So what I'm suggesting is that consciousness in practice would have to > depend on a physics actually capable of comprising its vehicles and their > environments and that evidently such a physics, to be viable, must be > quantum in nature. > > > I disagree. While quantum physics may be necessary to support our > carbon-based form of biological life, there could be non-quantum life > forms. Or, more particularly, classical Turing machine based consciousness, > whether or not you wanted to consider that as a life form. > You're disagreeing with an argument I'm not making. It's our own species of consciousness we must account for, since we are discussing the possible origins of our own particular situation as observers, namely carbon-based forms of biological life. Consequently, if we conjecture that such origins may lie in computation, the question then devolves on how phenomena within the observational spectra of TMs, as analysed for example in terms of the UDA, might display quantum-like features of entanglement, superposition and the like. I repeat that these phenomena might reasonably be assumed to be a prerequisite for our observing them, on penalty of the alternative conclusion that such features are merely arbitrary in this respect. > > > If so, this would likewise imply the observational selection of the > necessary physics from a more general background. > > > But even if it did imply the observational selection of the results of > quantum entanglement, you still have to give an account of how this comes > about. Or else you are just relying on magic. > > If CTM is assumed, this background would be computational and the > corresponding physics would be comprised by the 1-person-plural appearance, > via the FPI, of QM-like phenomena. On that assumption, Bruno attempts to > demonstrate (pace the current state of your discussion with him on this) > that the necessary quantum-like logic could in fact be derived from > classical computation, in the kind of infinite limit entailed by the UDA. > Or at least that the possibility of doing so has not yet been persuasively > ruled out. > > > I think the possibility of non-quantum consciousness in a non-quantum > world makes the success of this program less likely. > Why? You yourself aren't such a "non-quantum consciousness" are you? The question is rather whether your 'quantum-consciousness' could indeed be derived from a 'classical' computational basis. And, if so, whether the apparent predominance of this particular species of 'physical observation' (as exemplified by your current experience and the apparent history of your physical constitution) over possible alternatives can be rationalised in terms of relative measure or some other equally determinative argument. David > > > 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.
