Friday, May 04, 2007
Notre Dame Phil. Review of Strawson
For those interested, Leopold Stubenberg has a well-written summary of the recent special edition of the Journal of Consciousness Studies featuring Galen Strawson's panpsychism papers and 17 commentaries. (Hat tip - A brood comb's "power-blogroll"). My posts on this topic are here.
Posts
14 comments:
Hi Steve,
I read Strawson's fun target paper but haven't gotten my hands on the commentaries or his response yet. I read through the Stubengerg summary.
I'm sympathetic to Strawson's arguments. I'm not sure if you have already covered them, but similar cases have been put forward in two recent books by Griffiths and Rosenberg. I think both books went into further detail than Strawson in attempting to address the problems that panpsychism raises. Rosenberg especially emphasized the micro-to-macro or unity problem and the causality problems.
I also agree with your suggestion (in comments on your previous Strawson post) that a quantum substrate for consciousness could solve the micro-to-macro or unity problem. Rosenberg also suggested this, although given that he was already defending an unpopular viewpoint he didn't emphasize the quantum angle. I can't remember if Griffiths also mentioned the quantum possibility in a footnote or something....
I don't know how far you've gone in investigating this quantum possibility, but if you're just starting, "do not be cowed by physicists or philosophers of physics" or biologists either, who declare that macroscopic effects are impossible in the "hot, wet, chaotic" brain. The published calculations purporting to establish this impossibility (by Tegmark) assume the brain is at thermodynamic equilibrium, which is is not, since ATP energy is continually pumped through it. In fact a rigorous model by Frohlich (1968) shows how pumping energy through a system of electric dipoles (i.e. bio-molecules) can "condense" the system into a coherent state, at high temperatures. The observation of weak coherent photons radiated from living matter (by Popp & co.) supports that such coherent states are indeed present in living matter.
It is amusing to hear a professional philosopher say out loud some of the things I've thought myself, about how people can subscribe to apparently insane beliefs by getting themselves trapped in a conceptual box. His example is the denial of conscious experience by Dennett & co.; I also think of externalists about consciousness in the same way--i.e., people who believe that some or all the contents of consciousness are fixed by things outside the head, based on "silly" theoretical arguments about the referents of identical twin mental states and such. Apparently this is mainstream philosophy. Have you covered externalism on your site?
Cheers,
Mike
Hi Mike. Thanks very much for your thoughts. With regard to Gregg Rosenberg, his book, which I first discovered in 2004, made a big favorable impression (see posts here -- although I would write those posts a little differently today). With regard to Griffiths (Paul Griffiths?), could you give me a reference?
I firmly believe quantum effects play a non-trivial role in life and mind, but have no idea about the details. I hope enough biologists and neuroscientists are at least open to investigating the possibilities so that we might see some results in the not-too-distant future!
I don't think I've blogged much about radical externalism. I think some externalist leaning is OK and actually a necessary corrective to anyone who has a brain as disembodied computer paradigm model; but I agree with you that radical versions seem obviously incompatible with what we already know about the brain.
I also wanted to leave a link here to Jerry Fodor's review of Strawson for those interested (hat tip to David Chalmers' blog).
Yeah I actually found Strawson through that Fodor review.
Sorry, I misremembered the author of the other recent panpsychist book: it's by David Ray Griffin, called "Unsnarling the World-knot" (http://www.amazon.com/Unsnarling-World-Knot-Consciousness-Freedom-Mind-Body/dp/0520209443).
My amazon review reminded me that he also discusses the relevance of quantum theory. I read that one before Rosenberg so I didn't compare them in my review. Griffin is based on Whitehead; Rosenberg is based on his own theory of causality and "genuine individuals."
Thanks Mike. I don't buy into all of the ideas of Griffin and his process colleagues, but I liked and would also recommend "Unsnarling the World-knot". On many of the important ideas, Strawson and Rosenberg are right in tune with where Whitehead was 80 years ago!
Mike: also, thank you for your thoughtful comments on the older posts -- I want to follow up on these as well. - Steve
I'm starting to lose track of where I commented on the older posts...
Re: Rosenberg. It seems to me there were two ideas in there about how to solve the epiphenomenalism problem:
1) Qualia are the carriers of causality, so nothing gets done without them, or
2) Compound individuals (with corresponding qualia) can instantiate new higher-level causal laws not implicit in the lower-level.
Here's the issue I'm bothered about: solution number 2 would seem to have empirical consequences (that might map onto holistic quantum effects), but I think Rosenberg insists that his theory does not have empirical consequences. I like empirical consequences because it seems easier to avoid being labelled epiphenomenal if you have empirical consequences.
If we retreat to number 1 I can't decide whether to think of those qualia as epiphenomenal or not...and yet I find the idea very attractive.
Should I be asking this on a Rosenberg post?
Woops! "Paige" = "Mike" in the previous post. I accidentally logged in with my wife's account. Sorry.
Hi Mike:
Its fine to have the discussion here. Yeah, one of the drawbacks of the blog format is the way old posts get buried. After 3 years now I have trouble remembering some of the things I posted on here.
With regard to Rosenberg:
I guess we should distinguish between epiphenomenal meaning "has no causal impact" vs. "having consequences beyond what is empirically known."
So, your #1 is basically right, experience is the carrier of receptive properties necessary for causation in Rosenberg's model. Science, which by methodology only looks at effective properties, underexplains causality, but the patterns of effective properties detected are what they are and don't change because we have metaphysically explained causality.
You raise an interesting point in #2. In the model, receptive properties also bind systems together, allowing the composition of individuals (and new emergent behaviors) at various levels. I'm thinking that the point here is meant to be similar: science underexplains how natural systems clump together, but the description of the individuals won't change because of the theory.
But, thinking about our other discussions of the role quantum effects might be having in macroscopic systems where they are typically assumed to be absent, the discovery of these effects (which will be a real empirical development) might be a validation of the existence of something like Rosenberg's #2. That's an interesting thought. I'm not sure what he thinks about that.
I think it's on the last page of his book that he explicitly denies that his theory can have empirical consequences. But it still seems to me that particular models of the higher-level "receptive field" interactions could give you the kinds of "effective quasi-particles" that give rise to, e.g., superconductivity.
In the theory of superconductivity, you know charge is carried by the electrons, but if you just start doing calculations in terms of electrons you never find superconductivity. Rather, you have to "realize" that the electrons can form loosely bound pairs that interact very differently than lone electrons.
I'm not certain this is a valid example of the kind of thing Rosenberg is talking about, but it seems pretty similar.... I guess the crucial question is whether the superconducting pair states are derivable from the lone electron states in principle, if not in practice. If they are in principle derivable then maybe there is no "new higher level dynamic." But I think a field theory text book by Umezawa claims the pair states are NOT derivable in principle from free electron states.
Hm...maybe there's an easier toy example to work with, like EPR entangled states...
The superconductivity example seems interesting as do other macro-level phenomena (like liquid crystals, lasers, etc.?) where emergent behaviors occur. Maybe these have something to teach us about bodies and brains?
On the other hand, when it comes to the paradigm examples of coherence in quantum physics (EPR entanglement and superposed states) I'm not as sure about direct applicability. I know you disagreed with Tegmark's paper, but I'm chastened by how difficult it is to maintain coherence in experimental setups: witness the extreme practical difficulty involved in creating even a simple quantm computer.
"Emergence" is such a subtle and hairy subject. It seems clear to me that there can be no strong emergence in any classical physics model. But the community at large does not seem to have come to any consensus about that and they still argue about global parameters in chaotic systems and so on. So I feel lonely as I try to figure out if any of the quantum candidates qualify...
You make a fair point about how hard it is to maintain quantum coherence in experimental setups. But remember your laser pointer! Of course you can't compute much with it, but it shows that you can have quantum coherence at room temp by spending a few milliwatts of power. Frohlich's model describes a similar dynamic in a biological context.
So I guess what I'm suggesting is that quantum computer people are trying to do it the hard way, as compared to the way biological systems do it (if they do it at all). A number of people have talked about how dissipative systems (like us) can stabilize states against environmental noise, but I don't know whether experimentalists have tried this approach. Maybe no one can see yet how to apply this insight. If you're more familiar with the quantum computing literature or coherent state experiments maybe you've come across discussion of this alternative approach? Or maybe someone has already seen why this approach can never be practical?
In the meantime my feeling is that it is way to early to rule out quantum coherence in the exquisite structures in cells, and independent considerations (i.e. causally efficatious perceptual binding) motivate me to think it has to be the case. I mean, I think the experimentalists trying to make quantum computers and Bose condensates and such would admit the field is young.
How do you feel about my claim that you can't appeal to quantum mechanics to solve the unity (or combination) problem unless you accept a macroscopically coherent substrate?
Hi Mike: I missed seeing your last comment somehow which is why I didn't reply earlier.
I'll have to read more, but the quantum computer stuff seems to be about maintaining superpositions of micro-scopic quantum systems without reference to the kind of emergent coherent behavior of the kind you reference in a laser. This may be because you can't control and utilize the behavior in a large system like that. A biological system would have self-organized itself into its apparent use of such coherent emerged behavior.
On your last question, I would agree with that. Although the question of what different kinds of situations really count as coherence is still a bit fuzzy for me.
Hi Steve,
There was a quantum computation experimental paradigm where they used spin polarizations in some macroscopic fluid; I think it was billed as "quantum coherence in a coffee cup." I think they used a similar principle to an MRI machine. I think the lead guy on the study I saw was named Chuang.
Anyway that's still not using energy pumping like in a laser, as I'm suggesting biology might. I'm not clear on if or why the dissipative or pumping approach is considered not viable...I've just seen it mentioned on occasion, but without discussion.
Re: the binding/unity/combination problem (what do you prefer to call it?). So, have you given up on a solution to that one? Once you see that it is a problem, I think you also see it's a BIG one (not to say a HARD problem). It seems a shame, when you had the courage to embrace panexperientialism AND quantum mechanics, slaying the hard problem with a single stroke, and now you're balking at a mere improbability!? I'm teasing...it shows you're sincerely and honestly trying to weigh the evidence.
Cheers,
Mike
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