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Author
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Topic: Multiple Realizability---Once Again
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warren_bergerson
Member
Member # 262
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posted 02. June 2002 10:48
Leonid,
LA: May I give you an example from my professional area to show that physical science indeed does not know the path from the structure to the biological function?
An interesting example. I certainly agree with your conclusion that physical science does not know the path from structure to biological function. More specifically the suggestion or hypothesis that biological function is a necessary result of physical/chemical properties is not valid. In other words, physical/chemical determinism or simple physical/chemical determinism is not a valid premise.
The alternative, or at least one alternative, to this simple determinism is teleological causation or determinism. The teleological determinism ‘assumption’ would assert that a given set of physical/chemical properties can potentially determine a range or set of biological functions. The form actually expressed is the form consistent with the survival of the organism. Would you agree that this is a possible interpretation or assumption?
LA: To sum up, let me reiterate that the chemical, biochemical, cellular and organism levels of life breaking through each new step by locating the only possible narrow path allowed by homeostasis, which in its turn is strictly regulated by environmental factors, were paid in cold hard cash in the form of energy supply and the right to continue evolving.
If I understand this statement, then I don’t agree with it. I would not at all agree that there is only ‘one possible narrow path allowed by homeostasis’. IMO, survival is, or can be viewed as a form of homeostasis. There are many paths which lead to or can lead to this homeostasis. Furthermore, the paths are not found. The path which is compatible with survival at one point in time may not be compatible the next. Evolution is not about finding the ‘one narrow path’, but about continually finding and refinding not the path, but a path to survival that works at a point in time. Is the concept of ‘changing paths’ consistent with your approach?
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James A. Barham
Member
Member # 50
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posted 02. June 2002 21:52
While I am attempting to assimilate Leonid's and Warren's postings, I would like to try to bring the discussion back to the main topic of this thread: multiple realizability.
I do not mean to imply that I think there is only one approach to studying life that is valid. As a supporter of the concept of emergence, naturally I believe that multiple approaches are valid and even necessary. There are many possible levels of description or explanation in understanding biological function (that is, natural teleology), some of which would include:
(1) common sense or "folk psychology" (ends & means, beliefs & desires)
(2) logic (game theory, boolean networks, cybernetic control theory, "autopoiesis," Artificial Life, etc.)
(3) molecular biology ("informational" interactions among macromolecules)
(4) biochemistry (rate-dependent interactions, metabolic pathways)
(5) thermodynamics (equilibrium & nonequlibrium [open systems, "dissipative structures," etc.])
(6) nonlinear dynamics (network thermodynamics, damped and forced oscillators, simulated annealing, spin glasses, connectionist networks)
(7) bulk-phase condensed-matter physics (hydrodynamics, electrodynamics, crystal lattices, liquid crystals, phase transitions, order parameters, universality, renormalization group, etc.)
(8) polymer physics
(9) quantum coherence? (quantum field theory---Davydov, Frohlich, Ho, Del Giudice, Vitiello, et al.)
However, the question that principally interests me is whether the "emergence" of natural teleology can be "reduced" to logical relations (as Warren is arguing, if I understand him) or to ordinary chemistry and physics (as Leonid is arguing, if I understand him), or whether quantum coherence is ultimately required to provide a complete explanation.
The vast majority of philosophers and cognitive scientists seem to believe that the key lies at Level (2). If we can just hit on the right kind of abstract organization, then a system will "take off" and become alive (or even conscious), no matter what its material constitution happens to be. This is the idea behind the Turing test, Hal, Kismet, and so much of our popular culture. The idea is that the organization per se is the key to functionality; the matter is basically irrelevant. Even computer games can be considered alive for someone who is caught up in this mindset. Let us call this idea "formal emergence."
According to formal emergence, there is no real need to inquire below the level of (2)---the fact that terrestrial life incorporates specific mechanisms at lower levels in order to "implement" life as we know it is a mere accident of history. Life elsewhere in the universe, and artificial life that we may create in the future, will supposedly be totally different.
Now, my first question is, Does formal emergence make sense?
Any my reply is: No, it does not. Formal emergence is a mistake of historic proportions, a dead end due to uncritical, gee-whiz enthusiasm for computers and too many science fiction comics and movies. Why do I believe this? For many reasons, but above all because the causal powers of things derive from their material constitution, not their organization per se.
We get confused on this issue because we impose a certain organization on inert matter in the form of machines, and these machines serve our purposes. We say that machines have "functions," forgetting that their functions are FOR US, not for the machines themselves. The multiple realizability thesis loses sight of the fact that the connection between structure and function in a machine can only be considered arbitrary because the agency that is constituting the structure of the machine AS its function lies outside the machine altogether---in us.
True, we can use a hammer or the heel of a shoe to pound in nails. So a "hammer" is a kind of abstraction independent of its material constitution. But that does not mean that the same principle applies to living things. In living things, the agency that constitutes structure AS function does not lie outside the organism; rather, it lies inside the organism itself. In life, there is an INTRINSIC connection between the structure of organic matter and its function. (This is especially evident in the phenomenon of cryptobiosis, where metabolism is abolished---either through deep freezing or drastic desiccation---but the structure remains intact. When heat or water is restored, the organism begins to function normally again. This shows that the functioning of life is directly linked to its particular type of structure.)
Let us call this second view of natural teleology "material emergence" (that is what its friends may call it---its enemies will call it "vitalism").
Given that formal emergence is wrong, and material emergence is right, then my second question is: In order to understand natural teleology, can we stop at Level (8)? Or do we have to go all the way down to Level (9)?
And my answer is: No amount of cleverness in combining levels (1) through (8) is ever going to give a complete explanation of the phenomenon of natural teleology. Why? Just because there is nothing in levels (1) through (8) that can explain in physical, material terms how the massive coherence and coordination that constitutes natural teleology is possible. To do this, no combination of local interactions will ever be sufficient. Rather, there must be a physical principle giving rise to the global coherence and holistic responsiveness that constitute the intelligent agency of life, and such a principle is most likely going to be found in (9)---quantum coherence---at least, so far as we can see at present.
There is a great deal more that could be said, but perhaps I could pause here to ask for others' reactions to this way of posing the problem.
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Leonid Andreev
Member
Member # 282
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posted 03. June 2002 02:50
Warren:
1. I implied that the biological phenomenon was strictly determined physically and chemically and is intrinsically specific and teleological. The life seed with a powerful teleological potential has grown, through horizontal and vertical evolution, into the biosphere. You can’t really study it by the “let’s see what happens if we smack it with a rock” approach. The core of the notion of the biological is common for all what we call ‘living organisms’, but it cannot be discovered through singular experiments. The reductionism approach to investigation of life is merely a form of description of objects under study. On the other hand, both denial of the emergence of life and creationism are defeatism.
2. By ‘homeostasis’ I meant a purely quantitative factor that varies for various organisms and various environments. The core point to realize is that the essence of the development thrust is in the fact that upon overcoming each new barrier, the energy accumulation mechanism supplies energy for the next obstacle negotiation.
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warren_bergerson
Member
Member # 262
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posted 03. June 2002 10:54
James,
To answer your question, I think you first need to address the question "What is science?". If you view science as ‘the search for truth, the search for absolute truth, or the search for knowledge of how life really works’ then, IMO, the questions you ask can never be answered. There is no ‘real cause’ for anything. I believe it can even be demonstrated mathematically that the ‘real world’ involves an infinite number of causal structures.
Science in my view, is not the search for truth, but the search for practical human knowledge which can used to solve practical human problems. This view of science can be explained in terms of teleological causation. For any given problem, humans have a wide range of options or ‘potential options’. In order to pick the best available option, the option most likely to result in the goal of survival, humans need ‘reliable expectations or predictions’ of the likely outcomes of the choice selected. Science or the scientific paradigm, when rigorously applied, is by far the most powerful and effective of all known techniques for generating the reliable expectations needed to make the choices which make human behavior teleological. [If you are curious, human scientific behavior is a manifestation of certain key features of an LFS.]
Starting with the pragmatic or engineering view of science, the question of ‘explaining biological function or natural teleology’ becomes ‘What predictive knowledge or theories of biological function do we need to solve specific problems or survival problems?’ For rather obvious reasons, it is better to have a set of scientific theories or a knowledge structure which can be used to solve a wide range of problems. [As should be apparent, the scientific process takes huge amounts of energy or resources. The scientific method of problem solving is only ‘practical’ when it results in either ‘valuable’ solutions to very difficult problems or in knowledge structures which can be used to solve a wide range of problems. ]
Again, in terms of the pragmatic approach to science, the adaptive approach is based on the discovery (or claim) or assumption that essentially all problems involving biological systems can be analyzed and addressed in terms of teleological causation and the processes or causes which make causal relationships teleological. The adaptive approach is based on the further ‘discovery’, claim, or hypothesis that all the different processes responsible for creating and modifying teleological causation in biological systems can be modeled by a single paradigm.
It might be argued that these assumptions and hypothesis are consistent with what you describe as the widely accepted ‘logical’ explanation of biological function. I would agree with you, however, that this is not a complete explanation of biological function. In terms of the engineering view of science, a general model or theory is an important piece of knowledge needed to solve a problem, but it is not in itself all the knowledge required. [IMO, the view that a theory by itself constitutes an explanation is an outgrowth of the view that pure science is the work of scientific royalty and applied science is the work of scientific peons or commoners. This concept of scientific class distinction, IMO, has resulted in a seriously distorted concept of the scientific process. This distorted concept of science explains, IMO, many of the problems that exist today in the life sciences.]
I completely agree with your assertion that ‘formal emergence’ doesn’t by itself explain life or biological function. I would also agree that:
QUOTE JB- "According to formal emergence, there is no real need to inquire below the level of (2)---the fact that terrestrial life incorporates specific mechanisms at lower levels in order to "implement" life as we know it is a mere accident of history. Life elsewhere in the universe, and artificial life that we may create in the future, will supposedly be totally different."
this view of non-biological life is at least a great over-simplification. Life, biological function, and teleological causation as it occurs in life forms is a very complex paradigm or set of processes. While other forms of life could in theory exist, the complexity of the requirements involved would seem to make such alternative life forms somewhat unlikely.
While I agree with your suggestion that formal emergence is not an adequate explanation, I do not agree with your claim that biological function or teleological causation is in anyway intrinsic. In fact, as I view it, intrinsic and teleological are logically inconsistent. In the definitions I use, a causal relationship is teleological if it is part of a set of different ‘possible’ forms of the causal relationship, and the particular form that exists at a point in time is the form(or one of the possible forms) which increases the likelihood or expected likelihood of achieving some goal.
In the examples I have studied, teleological causation not only involved multiple possible forms, but the teleological or purposeful form was always highly changeable, dynamic or unstable. The form of a PCR which ‘served a purpose or function’ at one point in time, would not be teleological at another point in time. In the absence of processes to keep causal relationships adaptive or teleological, they quickly become non-adaptive(In the nervous system, for example, the adaptive form of the PCR which defines the information processing or input-output causal relationship in a neuron, changes every few milliseconds.)
I assume that your concept of intrinsic teleological causation, must be based on a definition of teleological causation which is different than the one I use. I would be interested in seeing how you define and model teleological causation.
Back to the subject on which we agree. In order to understand and explain specific occurrences of teleological causation, you need to identify, understand, explain, model and simulate the physical/chemical processes and mechanisms involved. You cannot, I would claim, understand and explain the evolution of the bacterial flagellum without identifying, analyzing, modeling and explaining the physical/chemical ‘teleological’ processes that generate the flagellum, the likely teleological forms from which the flagellum developed, and the physical/chemical processes which ‘caused’ the changes which produced the changes which resulted in the flagellum. The adaptive approach in no way reduces or eliminates the need to identify and explain the physical/chemical mechanisms underlying a process being analyzed. The adaptive approach does, however, provide useful guidance in identifying what types of physical/chemical processes to look for.
Again I think you are raising very good and interesting (at least to me issues). I will address your final question/comment in a separate post.
Warren
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warren_bergerson
Member
Member # 262
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posted 03. June 2002 11:40
James,
Your final question/comment was-
QUOTE JB: And my answer is: No amount of cleverness in combining levels (1) through (8) is ever going to give a complete explanation of the phenomenon of natural teleology. Why? Just because there is nothing in levels (1) through (8) that can explain in physical, material terms how the massive coherence and coordination that constitutes natural teleology is possible. To do this, no combination of local interactions will ever be sufficient. Rather, there must be a physical principle giving rise to the global coherence and holistic responsiveness that constitute the intelligent agency of life, and such a principle is most likely going to be found in (9)---quantum coherence---at least, so far as we can see at present.
To answer this very interesting question I will start with a story I remember from long, long ago. The setting is a castle somewhere with a King who claims no one can smuggle anything past his very observant gatekeepers. The hero of the story, one of those nasty little non-conformists, decides to accept the King’s challenge. Day after day, he brings to the castle gate his little red wagon filled with various items which the gatekeepers examine in great detail. Despite exhaustive searches, they find no contraband. As you may have guessed, the little boy succeeded in smuggling a whole lot of little red wagons into the castle.
To some extent, I think the ‘massive coherence and coordination’ observed in biological systems is explained, not in terms of some deep, hidden, physical process but in terms of the easily observed, and easily overlooked little red wagons. The massive coherence and coordination, which I agree clearly exists in biological systems, is the result of the interaction of many ‘simple’ and readily observable processes.
To use a similar analogy, it is difficult to visualize the ‘forest’ that is biological functionality, if you focus too closely on the ‘trees’ that make up that functionality. As I suggested in my earlier post, the explanation of the teleological nature of biological systems is easier to visualize if you start by asking questions like ‘how do I find a practical solution to this practical problem’.
When you start asking the question, ‘How does it really work?" you run into the problem of multiple realizability. When you dig down and analyze the details underlying one teleological process, you find one set of physical/chemical mechanisms. When you dig down and analyze the details underlying a second teleological process you may find a second very different set of physical/chemical mechanisms. The two occurrence of teleological causation, the adaptive approach suggests, share a common logical structure. The common logical structure does not however ‘explain’ both occurrences. To explain both occurrences you need to know both the shared logical structure, and the difference in specific physical/chemical mechanisms. [Note: The engineer in designing and analyzing bridges faces exactly the same issues. The engineer must be aware of both 1)general concepts and principles applicable to bridge construction, and 2)to the specific details associated with specific bridges and specific locations. ]
In reviewing the above comments, I realize I there is a not insignificant change I am not addressing the question you are asking. If this is the case, could you make another effort to restate the issue. Thank you.
Warren
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