|
Author
|
Topic: Natural selection and teleology
|
Mark Elkington
Member
Member # 120
|
posted 13. March 2002 20:51
James,
I've been enjoying your input here. A question on NS and teleology.
Say we have a self-replicating RNA strand which we place in some suitable environment such that replication with heritable variation occurs. Over time, differential replication and breakdown rates of "offspring" produce an "evolving" population, determined by natural selection. (I believe such experiments have been done, and the RNA sequences tend to shorten over time).
Is there any need to invoke teleology here? As far as I can see, this process is reducible to the laws of physics and chemistry (in principle at least; the inherent stochastic and nonlinear effects may make it impossible for us to model and predict actual outcomes).
Now say we use a more complex molecule, one which has metabolism as well as self-replication, and repeat the experiment with similar results. Again, do we need to invoke teleogy? At what level of complexity on this spectrum does this process cease to be reducible?
[ 13 March 2002, 21:11: Message edited by: Mark Elkington ]
IP: Logged
|
|
marcus
Member
Member # 117
|
posted 14. March 2002 03:15
James A. Barham writes:
quote:
I think that, by agreeing with mainstream Darwinian science that organisms are machines, ID commits the same mistake that they do. Rather, than proving "design" (i.e., by an outside agent), the design inference can just as well be viewed as a reductio ad absurdum of the premise that organisms are machines. I simply believe that the most promising way forward is to reject this premise, to admit what is apparently obviou---namely, that organisms and machines belong to entirely different metaphysical categories---and to see where this line of thinking leads.
Can we think of an immanent teleology in terms of the pleasure principle? Existence simply feels better than non-existence? At least that seems to be the case with human psychology. People commit suicide because that have greatly reduced affect in their relations with the world, and babies deprived of sensory stimuli become retarded and sometimes die.
If we're going to attribute intelligence to cells, why not go all the way and attribute sensory experience to them as well? And then why not hedonic sensory experience?
It seems to me that the really big dispute is over the proper use of mental or subjective language in science. Materialists, of course, want to ban it completely, but it seems to keep popping up. Intelligent design is considered non-scientific in large measure because intelligence is a subjective term, but it can be made to appear scientific through the concept of information. But the real difficulty for ID, as it was for the vitalists, is to show how subjective terminology can be given some degree of scientific rigor.
Of course, I have no idea of how statistical mechanics could deal with the question of subjectivity, but I have no problem thinking of micro-organisms as intelligent agents that want more and more subjective experience and so develop greater complexity just as a leaf spreads out to get greater and greater sunlight.
Subjectivity would be the crucial factor that would distinguish an organism from a machine and would also allow for both immanence and teleology.
When I try to contemplate who I am, that is, where my self-identity lies, I have to say that it is in my experiences and my memory of those experiences. It is not primarily my in my body or in non-sensory information. Maybe it's a crazy idea, but I see no reason why even the smallest organism couldn't be share this characteristic in some degree or another.
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 18. March 2002 09:46
Mark:
There are a couple of separate issues here, as I see it.
First, with regard to "naked RNA" replication, even in the experiments by Eigen, Spiegelman and others, the replication is not truly self-catalyzed, as I understand it, but rather depends on RNA synthetases being added to the test tube. So the RNA is not really naked after all.
But let's ignore that problem and pretend that RNA could replicate purely spontaneously, all by itself. In that case, I would have to agree with you. We would be dealing with a non-teleological phenomenon analogous to crystal growth.
However, the deeper question is, Is this the key to understanding life, as the RNA world scenario and most origin of life experimenters assume? Or is this a red herring, as the proteins-first theorists believe? (In the latter category, I would place Morowitz, de Duve, Dyson, the Foxes [Sydney and Ronald], among others.)
Naturally, I come down on the proteins-first side here. I simply regard metabolism as a more fundamental property of life than replication. The mere fact that proteins are simpler (in a statistical mechanical sense) than nucleic acids ought to make this obvious. I like Dyson's idea that nuclein acids evolved out of ATP, since the most fundamental symbiosis must be between proteins and ATP (and lipid membranes, of course). So, yes, I would say that metabolism is the key phenomenon, and replicationis secondary. Also, it should be pointed out that there is nothing at all resembling the Eigen scenario actually going on in the cell. Even in the bacterium, DNA replication is clearly under the control of the cell, it is not just occurring spontaneously. Here, the work of von Sternberg and others indicating that the genome should be regarded as essentially just another organelle out of many is fundamental, in my opinion.
Now, there remains the issue of how to understand the teleology that is manifest in cell organization. Here I am grasping at straws. I would simply refer to the work going on self-organizing systems theory (Kauffman, Fontana, Bak, et al.), nonlinear dynamical modeling of physiology (D. Mikulecky, F.E. Yates), and condensed matter physics (Mae-Wan Ho, Giuseppe Vitiello). No one has the answer yet, but it seems to me that these are the most fruitful lines of research being pursued at present. The problem of natural teleology is to explain the massive coherence and coordination of cellular processes, and these are the sciences than study collective and coherent phenomena. Makes sense.
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 18. March 2002 10:03
Marcus:
What you say about the possibility of subjective experience or consciousness in the cell is certainly not crazy. Lots of very thoughtful people (Whitehead, D.R. Griffin) would agree with you, and even extend some kind of experience below the level of life (panpsychism).
However, personally I would be more cautious. There are two major points I like to make in this regard.
First, I am a convinced emergentist, in the sense of P.W. Anderson's "more is different". I believe that emergence can be given a very rigorous scientific interpretation even quite apart from the question of life and telelology (see Robert W. Batterman's seminal new book, "The Devil in the Details"). As an emergentist, I am more comfortable saying that teleology (and possibly consciousness) emerge at the level of the living state, and are not evident below that level.
The second point I like to make is that while it is certainly conceivable that cells are conscious (i.e., that consciousness and teleology are co-extensive in nature), it is not necessary to assume so. The two have a very different epistemological status. The teleological organization of all life processes is simply an empirical fact that people can try to explain away if they choose, but which no one can deny on a purely phenomenological level. That is, it is apparent to us as outside observers in precisely the same way that it is apparent to us that the moon exists. Now, I am also a realist. Hence I believe the moon exists even when I am not looking at it. By parity of reasoning, I believe the manifest teleological properties of cells exist quite independently of our observations of them. Needless to say, we have no similar third-person access to the first-person states (if any) of cells.
So, in short, the problem of teleology and the problem of consciousness are conceptually distinct. Having said that, I admit there is something pleasing about the idea of identifying them. It may well be that cells, which surely strive to perpetuate themselves in existence, experience something vaguely analogous to pleasure in so doing. I have no problem at all with that. Unfortunately, the only evidence we have for consciousness is ourselves. Since consciousness seems to be closely associated with brains, we feel pretty safe in arguing by analogy to consciousness in other higher animals with brains. But whether each cell in my finger has its own dim consciousness is a much tougher question. I don't even know how to begin to address it scientifically. I guess the answer will have to wait on a much better understanding of consciousness at the level of the brain, and of teleology at the level of the cell. Then maybe the two bodies of theories can meet up somewhere in the middle.
IP: Logged
|
|
Bryan Cross
Member
Member # 51
|
posted 19. March 2002 22:55
James,
quote:
If we define natural selection as differential reproduction due to differential success of heritable functional variability, then it is clear that natural selection simply presupposes the notions of function and of success. Even the short-hand formula "survival of the fittest" makes this clear---"survival" is not a concept that can be cashed out in terms of physics and chemistry. It implies the active, intelligent striving of the organism to maintain itself in existence against the second law of thermodynamics. Function, success, fitness, survival---all of these are teleological notions through and through. Since natural selection presupposes these teleological phenomena, it cannot explain them.
How do the notions of ‘function’, ‘success’, ‘survival’, and ‘fitness’ presuppose teleology? Most philosophers of biology would disagree with you on this point. Whether these concepts are reducible to the terms of physics and chemistry is irrelevant to whether the biological processes they describe are reducible to ateleological processes or not.
quote:
The bottom line is that all life processes are functional or goal-directed at all times, in all generations.
This assumes that no life process could possible arise from a non-life process. Why should anyone simply grant you that assumption, for it begs the question against those who believe that life arose from non-life.
quote:
When new functional "traits" arise (whether via point mutations or in a more functionally directed way), they are immediately recruited into some functional system. The only traits that get transmitted are ones that are capable of functional recruitment in this way (otherwise, they would be lethal). So, there is no such thing as a non-functional trait that can have functionality magically conferred upon it by natural selection, as Darwinian philosophers like Dretske and Millikan argue.
Why should we believe that there can be no non-functional traits, or that non-functional traits cannot be transmitted? These appear to be mere assertions, and they clearly beg the question against Dretske and Millikan.
- Bryan
[ 19 March 2002, 22:57: Message edited by: Bryan Cross ]
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 19. March 2002 23:09
Bryan:
When I wrote that "all life processes are teleological," I was not addressing the issue of the origin of life, only making a statement about life once it has already gotten going. I agree that there there must have been a transition from non-life to life, or from mechanistic causation only to mechanistic causes teleologically organized for the sake of the whole.
I realize of course that most "philosophers of biology" do not agree with what I am saying---I am saying I believe they are mistaken!
As for begging the question, I would say that Dretsek and Millikan are doing that---they are simply assuming that natural selection successfully reduces functionality to mechanism, and then trying to understand higher-level cognitive phenomena on that basis.
The absurdity of their claim is most evident in the Swampman thought experiment---as though the mere fact of the "selection history" of a natual system per se could have any bearing on its occurrent causal powers. This is contrary to everything we know about the way the world works---in fact it is magical thinking. They commit this gross blunder because they are thinking about the way that human socially-constructed mental categories work, but I am claiming that this is altogether the wrong way to think about living matter. Whatever else we may say about the cell, surely its ability to act intelligently within its environment depends on its current material constitution. (The constitution itself of course will have a history, but that is not the issue.)
It is like trying to explain the fact that I know French and not German by explaining what classes I atended in College. Well, that's all well and good, but don't we need to say something about the actual synaptic weights of the nerve cell assemblies of the brain itself? My claim is that when we look at the functional abilities of cells, we must look for an analogous explanation---natural selection per se is just not enough.
IP: Logged
|
|
Bryan Cross
Member
Member # 51
|
posted 20. March 2002 00:44
James,
The only evidence I can find in your post in support of your position is the Swampman claim.
quote:
The absurdity of their claim is most evident in the Swampman thought experiment---as though the mere fact of the "selection history" of a natual system per se could have any bearing on its occurrent causal powers.
Why must anyone who denies that natural selection presupposes teleology claim that differences in selective history necessarily have any bearing on something's occurrent causal powers? It does not seem to me that anyone denying teleology must make this claim.
If you allow that teleology arose from non-teleological processes, then either the teleology is reducible (which is exactly what people like Millikan and Dretske argue) or you are appealing to strong emergence, which has its own problems. (See my thread titled Etiological Epicureanism and Intelligent Design.)
- Bryan
IP: Logged
|
|
Mark Elkington
Member
Member # 120
|
posted 20. March 2002 07:52
James,
Now, there remains the issue of how to understand the teleology that is manifest in cell organization. Here I am grasping at straws.
I think you're overstating the strength of your argument ![[Smile]](smile.gif) Seriously though, an essay by Dembski, The Act of Creation: Bridging Transcendence and Immanence, might be worth a read for some related ideas:
"...Supervenience is therefore an insulating strategy, designed to protect a naturalistic account of intelligent agency until a full reductive explanation is found. Supervenience, though not providing a reduction, tells us that in principle a reduction exists. Given that nothing like a full reductive explanation of intelligent agency is at hand, why should we think that such a reduction is even possible? To be sure, if we knew that naturalism were correct, then supervenience would follow. But naturalism itself is at issue."
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 20. March 2002 15:52
Bryan:
I have posted so many little snippets in so many places recently that I forget what I said where. So let me start from scratch, as it were, on the question of the way in which natural selection begs the question of teleology.
First of all, natural selection says nothing about the origin of new functions. It simply says that IF a new function (arising from we know not where) is better at what it does, relative to a population and an environment, then it will proliferate throught he population in subsequent generations. So, obviously the notion of function and also that of relative succes are presupposed here. But these are teleological notions! Natual selection cannot explain why organisms possess goal-directed functions, because it simply presupposes that they do, and then explain why certain ones proliferate instead of others.
It is kind of like saying that, if we have a widget factory, with a quality control inspector at the end of the conveyor who decides which widgets pass and which ones are discarded, then that explains widgets. But obviously it does not. The quality control inspector merely makes an up or down decision on what he is given, he doesn't create anything. Likewise, natural selection creates nothing. To explain biological functionality, we need to explain the factory itself.
Now, lots of people agree with this analysis. See, for example, W. Fontana and L.W. Buss, "The Arrival of the Fittest: Towards a Theory of Biological Organization," Bulletin of Mathematical Biology, 1994, 56: 1-64. Even Ernst Mayr would probably agree with what I have said so far. But where the mainstream mechanist-reductionist biologist would disagree is in the next step. He would say that everything is explained by biochemistry and molecular biology.
However, I disagree. There is absolutely nothing in conventional molecular biology that can explain the teleological organization of the cell. As many of the individual reactions as you wish---yes. The overall purposive organization---no. Molecular biology helps itself liberally to teleological concepts ("messengers," "codes," "proofreading," etc.). It must do so because nothing makes sense in the cell except in the light of functional logic. But molecular biology certainly does not explain the source of that functional logic.
So, in summary, in my judgment, neither natural selection, nor molecular biology, nor both together, can explain the teleological character of biological organization and biological processes.
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 20. March 2002 16:02
Mark:
I agree with what Bill says about "supervenience." I consider that a fairly useless philosophical concept. (Jaegwon Kim has an excellent critique of supervenience in his most recent book, Mind in a Physical World.)
I never speak of supervenience, I always speak of emergence. What's the difference? Supervenience is just a philosophical term of art, unconnected with anything in science. It is just a promissory note, to be cashed in later. Emergence is in a much stronger position, especially recently. It has been fairly rigorously defined within condensed-matter physics in terms of symmetry breaking and order parameters (new qualitative parameters that characterize the physical interactions characteristic of a particular length scale). The best book by far on this subject is Robert W. Batterman's "The Devil in the Details," just published.
Now, the question remains, of course, whether it is legitimate to suppose that this physical notion of emergence can be extended to encompass life. We have no idea how to do this at present, so it is perfectly understandable that ID folks should be skeptical. But then the question arises, what is the alternative? Is a supernatural explanation really a live option, from a scientific point of view? For some of us, it is not. But this gets us into a whole different set of issues. I would be happy to discuss them, but perhaps this is not the proper forum for that discussion.
IP: Logged
|
|
Moderator
Administrator
Member # 1
|
posted 20. March 2002 17:08
quote:
But then the question arises, what is the alternative? Is a supernatural explanation really a live option, from a scientific point of view? For some of us, it is not. But this gets us into a whole different set of issues. I would be happy to discuss them, but perhaps this is not the proper forum for that discussion.
James Barham is right. Just thought I'd point this out before the discussion enters into "a whole different set of issues."
IP: Logged
|
|
Bryan Cross
Member
Member # 51
|
posted 20. March 2002 19:11
James,
quote:
First of all, natural selection says nothing about the origin of new functions. It simply says that IF a new function (arising from we know not where) is better at what it does, relative to a population and an environment, then it will proliferate throught he population in subsequent generations. So, obviously the notion of function and also that of relative succes are presupposed here. But these are teleological notions! Natual selection cannot explain why organisms possess goal-directed functions, because it simply presupposes that they do, and then explain why certain ones proliferate instead of others.
If (as Millikan et al argue) activities become functions only when selected for, any function (including a brand new function) is the product of natural selection. So, I don’t see why Millikan et al should grant you that natural selection says nothing about the origin of new functions. Millikan et al might grant you that natural selection does not explain the origin of new activities, features, capacities, etc. that are not yet functions; but requiring her to agree that natural selection does not explain the origin of new functions would be requiring her to contradict herself.
But even if natural selection does not explain the origin of new activities, features, capacities, etc., this does not mean that these new activities, features, capacities, etc. cannot arise ateleologically. So you have not shown that natural selection presupposes teleology. If these activities can arise ateleologically, then natural selection need not presuppose any teleology at all. One of your pieces of evidence is that we presently don’t have any biochemical explanation for the organization of the cell. But absence of evidence is not evidence of absence. Your other piece of evidence is biologists’ use of functional concepts. But as I said before, biologists’ use of functional concepts shows absolutely nothing at all about whether those functions are reducible to ateleological processes or not. Most philosophers of biology believe that biological teleology is reducible to ateleology, and they use functional concepts all the time. The use of functional concepts by biologists does not indicate that the functions they are referring to are irreducibly teleological. This is because the use of functional concepts by biologists is perfectly compatible with all these functions being ultimately reducible to ateleological processes. So, I still see no reason to believe that natural selection somehow presupposes teleology.
- Bryan
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 20. March 2002 23:17
Bryan:
I realize that Millikan and philosophers of her ilk, and most practicing scientists, disagree with me. I am not impressed. I believe that they have not thought through their position far enough. I gave several reasons for this belief, none of which you addressed substantively.
I know that Millikan believes that selection turns a mechanism into a function. But this is sheer magical thinking. It corresponds to nothing we know about in nature. I believe it seems superficially plausible because it confuses a case like the difference between a genuine Old Master painting and a perfect fake---where it is the value that we place on the history that makes one valuable but not the other one---with the altogether different case of a natural system with its own inherent teleology. In the latter case, it is not the selection history per se that creates function, but rather the dynamical change undergone by the system that causes an adjustment in its functional powers.
As for the biologists, I know they think there is no problem about reducing everything to mechanism, but until they can show me how you get the fantastically complex coordination of the cell out of biochemistry, I will beg to differ.
Maybe there is a sense in which we are talking past each other. I, too, believe that there is a physical explanation for this teleological coherence and coordination. It is just that I believe it is an emergent phenomenon that transcends mechanistic interactions---something specific to the living state of matter which we do not properly understand yet. Maybe, if pressed, that is what the biologists you speak of would say, too. But I doubt it. I think that most mainstream scientists have convinced themselves that teleology is somehow unreal, that it would all disappear if we just knew all the biochemical details. I just don't buy it.
It is interesting that an increasing number of fairly mainstream thinkers are willing to admit publicly that the emperor has no clothes---i.e., that the reductionist faith is incoherent. See, e.g., Franklin M. Harold, The Way of the Cell, and Stephen Rothman, Lessons from the Living Cell, both recently published by well-respected researchers (and entirely secular thinkers, so far as one can tell), but both of which are saying the same thing I am saying---teleology is real and it is irreducible to mechanistic causation. (Many other thinkers have made the same point in a more sophisticated way---Robert Rosen, F.E. Yates, Howard Pattee, and many others---I only mention these two because they have been mainstream laboratory researchers who are finally going public with their doubts.)
IP: Logged
|
|
Bryan Cross
Member
Member # 51
|
posted 21. March 2002 01:08
James,
You argued that natural selection presupposes teleology. But I showed that if biological functionality has an ateleological explanation, then natural selection does not presuppose teleology. Hence your claim [that natural selection presupposes teleology] assumes that biological functionality cannot in principle be explained ateleologically. In other words, your argument begs the question.
You claimed that all the mechanistic processes in living things are organized in such a way as to achieve proximate goals, with the ultimate goal of maintaining the life of the organism. This is not a controversial claim, since most everyone would acknowledge this.
You went beyond that, however, to make the stronger claim that mechanistic (ateleological) processes cannot produce the teleological organization of living things. But you have offered no substantive support for this stronger claim. I went back and read each of your posts in this thread, and the only evidence (I can find) that you have put forward in support of this stronger claim is:
(1) biologists’ use of functional language/concepts
(2) the absence of evidence showing how biochemistry and molecular biology produce teleological organization
(3) the Swampman example
(4) the fact that some other academics agree with you
I showed why biologists’ use of functional language proves nothing about the teleological nature of the processes to which this language refers. I also pointed at that the absence of evidence is not evidence of absence. I also pointed out that the Swampman example does not show that biological functionality cannot have been produced through an ateological process. Lastly, the fact that some reputable people agree with you enhances your credibility, but it isn’t direct evidence in support of your position. I am interested in this subject, and I am open-minded to the possibility of irreducible biological teleology. But at least in this thread you have not provided any substantial evidence that biological teleology is in principle irreducible to ateleological processes.
What you are left with is the mere assertion that natural, mechanistic (ateleological) processes cannot in principle produce teleological organization. To deny this is, in your view, “sheer magical thinking”. But that is an ad hominen. Millikan could just reply that you are guilty of “sheer uncreative thinking”, and the debate would not be advanced by these sorts of comments. In your view, Millikan’s view “corresponds to nothing we know about in nature”. Well of course; we have only been observing nature for a nanosecond in evolutionary time. Hence, if we haven’t observed natural processes producing teleological organization, this tells us nothing about whether such a thing is possible. Do you have any real evidence that mechanistic (ateleological) processes cannot in principle produce teleological organization?
- Bryan
IP: Logged
|
|
James A. Barham
Member
Member # 50
|
posted 21. March 2002 17:46
Bryan:
Perhaps you would grant me a substantive disagreement with Millikan (instead of accusing me of begging the question) if I had worded my claim differently. Let me try again.
Millikan is claiming that natural selection naturalizes functionality. I am claiming that her claim is false, that she has not achieved what she claims to have achieved. How is that begging the question??
What is my argument that her claim is false? That the principle of natural selection itself relies on the teleological organization of the organism surreptitiously. I think that even Millikan would agree that to make good on her claim, she has to have an account of function that does not itself involve teleology anywhere along the line. But natural selection by itself does not meet this criterion, since in its logical structure it assumes the prior existence of the organism as a functionally organized system.
Probably, Millikan herself would reply, like Mayr and other Darwinians usually do, that, okay, Barham is right, natural selection alone can't do the trick, but that molecular biology with the aid of natural selection can. But molecular biology doesn't help, either, because it too is replete with teleological concepts (messengers, proofreading, etc.). In general, molecualr biology simply assumes that molecules have functions and explains how these functions are carried out in biochemical terms. But molecular biology has no conceptual resources with which to explain what it is about the individual biochemical reactions that makes them functions. What the molecular biologist will then do, when confronted with this problem, is pass the baton back to selection theory.
In short, we have a shell game going---whichever you theory you look under, the final reduction of teleology to mechanism is always underneath the other one.
By the way, when I said that Millikan's use of natural selection to bestow functionality on what would otherwise be a mechanistic process was "magical," I did not mean it ad hominem (that is, I was not claiming that she as a person is prone to magical thinking). I meant that the claim itself is magical, in the sense I indicated---namely, it corresponds to nothing that is material or physical or causal, nothing that could make a real difference in the real world (except at the human level, where the way we choose to regard things itself determines the way we interact with them). She is confusing the way that humans determine the functions of their tools and social constructs with the way that material systems work---which is in virtue of their intrinsic causal powers. This goes back to the fact that organisms and machines belong to distinct metaphysical categories.
Now I realize full well that none of this is likely to convince Millikan (or perhaps you), but will you at least admit that this is a substantive dispute, and not merely "question begging"? Anyway, the dispute is only partly conceptual; it is also partly empirical. Namely, What is, empirically speaking, the reason for the massive coherence and coordination of the individual biochemical reactions in the cell?
Therefore, I would like to hear my actual arguments addressed in rebuttal. I do not feel that Darwinism is automatically the default position and that all the burden of proof is on my shoulders. Let the Darwinian justify himself (or herself), as well!
IP: Logged
|
|
|
Printer-friendly view of this topic