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Author
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Topic: GA evolves 1,800 bits of CSI?
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Micah Sparacio
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Member # 6
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posted 23. March 2002 13:05
James,
I think a necessary distinction needs to be made between "organisms as machines" and "systems within organisms as machines". In other words, there are certain biological systems that can be properly addressed as machines. I think ID theorists would agree with me on this. Whether or not organisms can be understood as machines themselves, or whether they extend beyond the machine analogy is a question that I think is still up in the air.
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Mark Elkington
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Member # 120
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posted 24. March 2002 06:27
James,
One definition of emergence is: "a property of a set of elements, which is neither explicable nor predictable solely on the basis of the properties of those elements together with some simple aggregative operation such as addition, multiplication, or integration (in the math sense)"
Just some clarifying questions. In your own understanding of emergence, is causality broken or transcended in some way?
In the above definition, what could make an emergent property not explicable or predictable from the lower level, at least in principle? Quantum non-determinism?
In thinking about machine vs. organism, if an organism can function solely by and in accordance with natural physical laws (i.e. without ongoing supernatural intervention), then irrespective of its origin, it could qualify as a machine using this as one criterion of machine-ness. How useful or relevant that criterion is is another question again.
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James A. Barham
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Member # 50
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posted 24. March 2002 11:38
Micah: Thanks for the clarification.
That is very frank, and I find it helpful. Certainly, I agree that many of the individual reactions in the cell are best characterized as linear or mechanistic, so if ID is willing to leave open the possibility that mechanism is transcended at the level of the whole cell, there is a lot of room for agreement between ID and self-ogranization theory.
Mark: On Emergence:
There are a number of related but distinct issues here. First, I want to suggest that the word "cause" be allowed to refer to any sort of intrinsic natural process whatsoever, and not be restricted by definition to a linear or mechanistic form of cause and effect relation. Now this is a merely verbal point, but if you are willing to grant it, it makes it easier to discuss the idea that there are different forms of "causes," and that causality itself has evolved over the course of cosmic evolution (an idea especially associated with the German physicist Walter Thirring).
The basic idea is that the universe started out relatively uniform and featureless, and has acquired structure through a succession of symmetry breaking events. As Pierre Curie wrote a century ago, "It is the dyssymmetry that creates the phenomenon." Now, it seems intuitively obvious that you can't have the laws governing solid matter before solid matter exists, or the laws governing life before life exists. So, that is the sense in which the laws of nature, or causal principles themselves, have evolved. But at the same time we want to acknowledge that the potential was there all along, and we want to understand how the laws unique to the various levels of reality are nevertheless related to each other, and are not just arbitrary.
This is where quantum field theory comes in. According to the "effective field" interpretation, each length scale has associated with it a characteristic "order parameter," which is emergent with respect to lower levels in terms of its actual content, but continuous across levels in terms of its form. The "form" in this context is given by the renormalization group, which is a mathematical technique for basically throwing out negligible terms in your equations and rescaling the few terms that are really important for governing the physics at a given length scale.
So, in short, the emergence lies in the "more is different" principle---longer length and time scales give rise to new order parameters and new qualitative behavior. But the universality lies in the fact that the renormalization technique allows us to fold all levels into a common theoretical structure, basically repeating the same procedure at each level.
There are a lot of things to say about this. One set of issues deals with the epistemology/ontology distinction. Many physicists (especially particle physicists) are die-hard reductionists and would stress that the renormalization methodology is a makeshift reflecting our ignorance of the details. But I do not see any justification for this claim. The only reason we ever have for believing that our theories have hold of reality is their success, and the renormalization technique is extraordinarily successful. I take this to mean that reality itself is indeed hierarchically structured.
The other problem of course is whether this whole scenario can be extended to life itself. That is the most controversial part of what I am saying. But I do not see any good reason in principle why it couldn't. I view it as an open question that future scientific progress must determine.
Another thing to stress is that this picture puts paid to Laplacian determinism at all levels, not just at the transition to life. Solid matter itself is fully emergent in this sense. There is no way, even in principle, to derive the properties of solid matter analytically from the lower-level laws of quantum mechanics. The rigidity of crystals arises from the long-range interactions among the Goldstone modes (called "phonons" in this context), which have no existence at all apart from the crystal itself. They are a global property of the crystal state as such.
What I want to say is that there must be some analogous holistic modes associated with the lviing state. I have speculated that they may be connected with the "minimum frustration principle" in proteins articulated by Hans Frauenfelder, but I am no physicist, so I wouldn't want to place much stress on that. It is just something that I find heuristically suggestive.
The other point to stress is that once we get beyond the idea that "cause" inevitably implies mechanical (or linear) causation and universal determinism, then the important issue for life becomes not determinism, but rather energy.
A hurricane is not "deterministic" or even strictly mechanistic (because it has nonlinear, many-to-one causality, which breaks time symmetry), but it is still the result of pure energy minimization. What life seems to be adding to such nonequilibrium, self-organizing systems, is the ability to coordinate its activities with external conditions in a predictive way---as though the cell or even the protein were saying to itself---Wait, wait, Ok now, go for it---where the timing of the action is coordinated with external conditions in the "appropriate" way, where appropriate is cashed out in terms of the continued dynamical stability of the system conceived of as a nonlinear oscillator.
In short, this kind of functional causality is sui generis or emergent at the level of life, but still not just a miracle, but something tha can potentially be understood as just another level in the "tower" of emergent levels described by effective field theoy.
Another way of looking at is this. In the philosophical literature on the mind-body problem, it is always stressed that neither determinism nor indeterminism can buy us free will. What is necessary is a third, independent form of causality which acts according to reasons, and does not just minimize energy. This is what is going on the cell (call it "agent causation" if you like), and this is what condensed matter physicists are now struggling to understand.
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Mark Elkington
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Member # 120
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posted 25. March 2002 07:27
James,
This is stretching stuff. O that the universe was assuredly a Newtonian-Laplacean clockwork of linear causal chains! Certainly quantum mechanics overthrows strict determinism. I'm trying to come to grips with the concept of "circular causality," which I'm guessing is what you're referring to?
Time seems to be a key concept here. Linear causality requires "the strict temporal order between the antecedent cause and the subsequent effect. No effect can precede a cause, but every cause is an effect of a preceding cause." In contrast, circular causality allows "simultaneity in the bidirectional flow or exchange of influences, which are not merely 'very fast', but which transcend time and space and become nonlocal in their conjointness."
One question that springs from this for me is, Is circular causality just a workable way of modelling an underlying reality of unmeasurable micro linear causal component events? The definition given seems to suggest more than this, i.e. time is in some sense "transcended" altogether.
Is the term "nonlocal" used here formally related to quantum nonlocality, or is it a less rigorous, illustrative use of the concept? It's hard to imagine the former being possible, in which case we come back to, as you described, a "verbal" point, but one that's hard to pin down. Not denying though the possible usefulness of allowing this and exploring where it may lead.
Renormalisation sounds like a hierachy of black box approximations, but perhaps only when using reductionistic presuppositions. A question on the crystal example. If I had an N-order simulator, with large enough N, could I not in principle model a crystal with sufficient resolution to include phonons in the model? Would this give them an "existance" aside from the actual physical entity itself? Or would they be themselves a corresponding emergent proprty of my simulator?!
I agree that "neither determinism nor indeterminism can buy us free will." Indeed, closely bound with that idea is the definition I gave for non machine-ness, which could be restated as, "a third, independent form of causality which acts according to reasons" in the ongoing operation of the organism. The implication being that organisms without free will are machines, and organisms with free will (= moral accountability?) are not. That might take some unpacking and justifying ![[Smile]](smile.gif)
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James A. Barham
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Member # 50
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posted 25. March 2002 08:14
Mark:
On "circular causality": I am not at all trying invoke any sort of effect of the future onto the past. On the contrary, I am a convinced "temporalist," in the sense that I believe the process of becoming is real, not some sort of perspectival illusion. On this view, the future does not yet exist, therefore it can scarcely have any real effects.
All that is required, in my view, is cyclicity, but of a special sort. Ordinary cycles in inanimate objects (pendulums, hurricanes) are just minimizing energy under constraints. Life is certainly doing more than this, and this "more" currently eludes us. However, F.E. Yates speculates that ultimately living processes may be fruitfully modeled as highly nonlinear oscillators, and I have added the element that they are coordinated with external conditions via a low-energy trigger, and that this is what allows them to act intelligently on the world.
This is not backward temporal causation and it is not clairvoyance; it is just acknowledging that intelligence consists in the ability to recognize favorable circumstances for functional action, based on past experience. Nearly all living processes can be analyzed as trigger-dependent nonlinear oscillators in this way, from enzymes on up. It is just a model, of course, and it is so abstract as to be of little scientific value. However, I think it has heuristic value for the philosophical problems that concern us.
On the global/local distinction: There is a crucial distinction between the global coherence that follows from quantum field theory and the nonlocal or entanglement effects found at the elementary particle level in quantum mechanics. We are talking here about very large-scale objects in relation to quantum non-locality, so I try to steer clear of that whole set of issues, which seem not too relevant to life. But quantum field theory, which is our mainstream theory of macroscopic objects, is obviously another matter altogether.
On the N-order simulation: As I understand it (and, again, I emphasize that I am no physicist---I just do the best I can with this literature), there is no way to predict the qualitatively new emergent properties of the new higher level system as we travel up the "tower" of effective field theories. At each new level, the characteristic "order parameters" have to be discovered experimentally and then put into the equations "by hand." So, no, the rigidity of solid matter cannot in fact be predicted by your N-order simulation. At least, that is how I understand it. I can direct you to the literature if you like, or if you know of some literature that contradicts this interpretation, I would very much appreciate your sharing it with me.
On free will: My claim is that all living processes involve functional actions which involve both a conative (or striving) and a cognitive (or intelligent) element, that are irreducible to mechanistic causes alone. This is going to have to be cashed out in terms of Yates's homeodynamics and ultimately condensed matter physics.
I do believe that this is the basis of free will; however, I believe that free will (or voluntary action) is a relative attribute, not an either/or matter. Clearly a dog has a lot more of it than an amoeba. Basically, I think it is a matter of the number of competing motivations and reasons and instrumental informational inputs than can be integrated by the organism in question. As for human beings, and morality, that is a whole different emergent level---one which I have addressed tentatively in my "Back to the Stoics" paper that was available in the ISCID archives (I don't know if it is still there now)---but perhaps a question for a different forum.
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Mark Elkington
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Member # 120
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posted 27. March 2002 17:24
James,
I'd be interested to have a look at some of the literature on effective field theories, order parameters, crystals etc, if you have some references. I don't know of any specific counter examples relating to our discussion.
I'll give your Stoic article a re-read over the weekend.
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James A. Barham
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Member # 50
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posted 27. March 2002 19:01
Mark:
I am unable to use highly technical material, so this is a sort of QFT lite list, but here goes.
The best single source on QFT written for a general philosophical audience is Tian Yu Cao's Conceptual Developments of 20th Century Field Theories, Cambridge UP, 1997.
An excellent short article on the effective field theory version of QFT is Howard Georgi's "Effective Quantum Field Theories," in Paul Davies (ed.), The New Physics, Cambridge UP, 1989, pp. 446--457.
The most important discussion of ideas coming out of QFT for philosophy is the brand-new book by Robert W. Batterman, The Devil in the Details, Oxford UP, 2002. This is a pathbreaking book that every philosopher ought to read carefully, in my humble opinion.
There are a number of good articles for a general intellectual audience which develop the "moral" of QFT for the doctrine of emergence.
The most famous by far is of course the seminal article by Philip W. Anderson, "More is Different," Science, 1972, 177: 393--396. See also the recent follow-up by Anderson, "More is Different---One More Time," in N.P. Ong and R.N. Bhatt (eds.), More is Different: Fifty Years of Condensed Matter Physics, Princeton UP, 2001, pp. 1--8.
There are quite a few other good articles in a similar vein. Two of my favorites are T.Y. Cao, "Monism, but not through reductionism," in Robert S. Cohen and Alfred I. Tauber (eds.), Philosophies of Nature, Kluwer Academic, 1998, pp. 39--51
and Sylvan S. Schweber, "The Metaphysics of Science at the End of a Heroic Age," in Robert S. Cohen et al. (eds.), Experimental Metaphysics, Kluwer Academic, 1997, pp. 171--198.
Note that none of the above really deal with biology. The best two books by far that do discuss biology from at QFT perspective are Giuseppe Vitiello, My Double Unveiled: The dissipative Quantum Model of Brain, John Benjamins, 2001,
and Mae-Wan Ho, The Rainbow and the Worm: The Physics of Organisms, World Scientific, 1993.
If you know physics and can follow the math, then you might want to use:
P.M. Chaikin & T.C. Lubensky, Principles of Condensed Matter Physics, Cambridge UP, 1995,
or Alexei M. Tsvelik, Quantum Field Theory in Condensed Matter Physics, Cambridge UP, 1995,
or Robert E. Marshak, Conceptual Foundations of Modern Particle Physics, World Scientific, 1993.
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