On 23 August 2014 23:50, meekerdb <meeke...@verizon.net> wrote: *You're saying it may be incoherent to reduce consciousness to computation, if computation is reducible to physics? Why would that be incoherent? Must 'reduction' necessarily be reduction to the bottom to be coherent? Or are you assuming consciousness can't be reducible to physics therefore it can't be reducible to some intermediate (computation) that risks be reducible to physics?*
No, I'm definitely not saying, in principle, that consciousness couldn't be reduced to physics. Indeed my whole point has been that if computation is, in the end, nothing over and above physical action, any theory that links consciousness to computation is tacitly a claim that consciousness is itself nothing over and above physical action. That claim may be true, but it can't be a claim about computation, only one about physics. Indeed, your own "engineering-level" analogies exploit precisely this ambiguity. You have yourself expressed the view (re Tegmark's ideas, as I recall) that mathematics is a human invention: i.e. a collection of abstractions from physical reality. On that basis, the very notion of computation *could only be* a meta-mathematical metaphor approximated by certain classes of physical action. I'm grateful to Bruno for pointing out that CTM, taken seriously, rather than being merely a "psychological" theory riding on the coat-tails of physics, must entail a profound "reversal" of explanatory priority. I have no idea whether this insight will lead, in the end, to a correct TOE, but it seems clear that it does require computation to take explanatory priority over physics. David On 8/23/2014 9:09 AM, David Nyman wrote: > > On 23 August 2014 05:02, meekerdb <meeke...@verizon.net> wrote: > > *What we observe in practice are physical devices of various kinds > (indeed, in principle, indefinitely many kinds) that we accept FAPP as > adequately instantiating particular classes of computation within certain > fairly stringent limits.* > > > *What we observe, aside from observing our own thoughts and maybe even > then, is always theory laden. Partly we see the world through a theory of > objects that evolution has provided us, sort of naive physics, but a theory > nonetheless as optical illusions demonstrate.* > > > And the relevance of this remark to my point is what, precisely? > > > Just a cautionary remark that observing a physical device already involves > assumptions that it is an experience that can in principle be shared and > agreed on by other observers - i.e. that it assumes some physics. > > > > *To put it another way, we are prepared to interpret the normal > physical behaviour of such devices *as if* it instantiated the mathematical > notion of computation.* > > > *Right, because it usually (modulo a dropped bit or so) does.* > > > Obviously. And your point is...? > > *These considerations should make it clear that any description of > the normal behaviour of a physical device as computation can only be in a > sense that is, ultimately, metaphorical.* > > > *I think you are too hung up on ontology. You denigrate everything > that's not in terms of the ur-stuff of (some unknown) true ontology as > metaphor or fiction. Why not accept that knowledge, including knowledge of > ontology, is always provisional and uncertain and it's best to think of it > as a model summarizing our best idea - but not necessarily the one TRUE > idea.* > > > Maybe you are getting a little too hung up on what you imagine me to be > hung up on. If that is the case, it might make you somewhat unreceptive at > the outset to what you assume to be my line of argument. I'm not trying to > grind any axe in particular but only to articulate what I suspect are > sometimes unrecognised assumptions as clearly as I can and then examine the > consequences. Of course I may well be wrong on any point and so my aim is > to encourage discussion from which I might learn. > > In this particular case what I'm driving at isn't that either matter or > computation need be considered as some kind of mystical "ur-stuff" > (whatever that would be). What I'm questioning is whether it is really > coherent to attribute *first-person* consciousness to "computation" against > the background of any theory that is committed to a physically primitive > level of explanation. > > > You're saying it may be incoherent to reduce consciousness to computation, > if computation is reducible to physics? Why would that be incoherent? > Must 'reduction' necessarily be reduction to the bottom to be coherent? Or > are you assuming consciousness can't be reducible to physics therefore it > can't be reducible to some intermediate (computation) that risks be > reducible to physics? > > > I know you cross swords with Bruno over the meaning of primitive in > this context, but I don't see why this has to be problematic. Primitive > simply means the level of explanation to which it is *assumed* every other > level can be reduced. > > > I think we only "cross swords" when Bruno implies that any reduction of > consciousness to physical processes is the same as asserting that some > (undefined) physics is primitive. The way theoretical physics has > developed over the last century I wouldn't be surprised if someone > developed a fundamental theory of physics based on homotopy theory or knots > or numbers. But it wouldn't affect the reduction of chemistry to physics > and it might not affect the reduction of computation to physics. I take > "physics" to mean the most fundamental science of what we can empirically > agree on - whatever it's ontology is. I think Bruno only differs in that > he thinks we can agree on things that are not empirical, like arithmetic. > > > The point is not that we can know any particular theory of this sort > to be TRUE, but only that we should rigorously pursue its consequences *as > if it were*. > > My point then is that we should start by treating a theory of physical > primitivism "as if true". If so, it is only consistent to suppose that any > phenomenon under consideration in terms of that theory must be assumed to > be adequately and fully accountable (at least in principle) at its lowest > level of physical reduction. You persistently demur from this line of > argument, but I think you miss my point, which is entirely harmless in > every case except (I contend) that of the "1p part" of consciousness. It is > entirely possible to understand a physically-instantiated computation (and > hence, on CTM, an associated state of consciousness) to be the same > physical process regardless of the "level of reduction" at which it is > considered. After all, any such "level" is, in the end, merely a term of > art associated with the theory in question. But what I'm questioning is > whether it is coherent to (tacitly) treat the 1p part as merely such a term > of art. > > > ?? Does "term of art" imply a third person description? > > > > My sense is that you equivocate on this, because if we only consider the > 3p part (as in your analogy of the Mars Rover) the point (i.e. > 3p-reducibility) is indeed harmless. But the 1p part resists 1p-reduction. > It stubbornly is what it is. Hence my question essentially is about the > kind of theory required to make sense of associating an irreducible 1p part > with a reducible 3p part. AFAICS such a question cannot even be posed > coherently in terms of physical primitivism. > > > Suppose that you have a theory which reliably tells you which 1p qualia go > with which 3p brain processes (the engineering level solution to the > mind-body problem). Does that "make sense of associating an irreducible 1p > part with a reducible 3p part."? Or are you saying that such an > association can't be a brute fact? > > > > Indeed you have suggested that it is unreasonable to ask for this. > What inclines me to Bruno's ideas (assuming CTM of course) is that this > particular question may be better posed in terms of a theory that takes > computation, not physics, as its primitive. > > > Yes, I agree that it might be. But even if it provides a better answer to > the relation of qualia to brains, that doesn't make it a better TOE if it > can't solve the "white rabbit" problem. It will just have traded one > problem for another. > > > > I think the remainder of your remarks equivocate on precisely this 3p-1p > distinction, so I won't comment on them specifically. If I've read you > wrongly on this I'd be grateful for clarification. > > > No, I think that's a fair reading. As you note, I don't think it's > possible to have a 1p-reduction of the 1p part (if I understand what you > mean by 1p-reduction). I think the engineering level solution may be the > best that can be done. > > Brent > > -- > 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 everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://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 everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
