Complexity

Discussion in 'Health and medical' started by Chupacabra, Apr 14, 2004.

  1. "Tim Tyler" <[email protected]> wrote in message
    news:[email protected]...
    > Guy Hoelzer <[email protected]> wrote or quoted:
    > > Jim Menegay at [email protected] wrote on 4/28/04
    2:44 PM:
    > > > Guy Hoelzer <[email protected]> wrote in message
    > > Cosma Shalizi offers some criticism of the whole idea -
    and winds up
    > offering a purely mem
    > > > And, I think that the whole field of "complexity" is
    plagued by bad
    > > > choices of terminology and some very, very bad
    intuitions.
    > > > Furthermore, I don't see the situation as likely to
    improve when
    > > > books can be sold by coining meaningless, but
    evocatative, phrases
    > > > such as "the edge of chaos". IMO.
    > >
    > > "Edge of chaos" is much more than a catchy phrase. Do
    you know what it
    > > means in this context?
    >
    > "Edge of chaos" *is* an evocative phrase.
    >
    > However... subsequent researchers generally failed to
    confirm Langton's
    > suggestion that the location might be of interest in terms
    of being a
    > particulary attractive spot for performing computations -
    and his Lambda
    > parameter hasn't actually proved to be of much use :-(
    >
    etic explanation for the existence of the phrase:
    >
    > ``Given that that the opinion of specialists was never
    unanimous behind
    > ?life at the edge of chaos,? and there is every
    possibility it?s wrong,
    > why was this idea picked up by some segments of educated
    opinion and
    > adopted? ? even adopted pretty widely; I seem to recall
    Al Gore making
    > some hay with the notion, and hearing that it was being
    touted by
    > management witch-doctors. The obvious answer is that it
    fits nicely with
    > some wide-spread prejudices: basically, antinomianism, a
    dislike of
    > rules and rigidity and formality, a positive relish for
    rule-breaking.''
    >
    > -
    http://cscs.umich.edu/~crshalizi/notebooks/edge-of-
    chaos.html
    >
    > However... I have to number myself as among those who
    thinks that
    > there really /is/ something to Langton's intuitive idea
    ;-)
    >
    > "Self-organised criticality" (e.g. the
    pile-of-sand/landslide effect)
    > is the simplest way I know to clearly illustrate to
    sceptics that
    > there really /is/ something to the notion that complex
    systems can
    > tend to migrate towards the "edge" of zones where chaotic
    behaviour
    > arises.

    Perhaps another example of such "Self-organised criticality"
    (or at least a similar idea) that is easier to rationalize
    is the formation of substances into different allotropic
    forms when stressed by differing environmental conditions
    such as temp., pressure, or other energy constraints--the
    formation of water into several different forms of ice, or
    carbon into graphite, diamond, or buckeyballs/tubes, are
    beautiful examples of compounds or elements "evolving" under
    stress to go from one quantitatively changing-properties-
    regime, through transition points, into another,
    qualitatively different regime, then so on into others
    (allotropes having radically different properties such as
    structures, densities, etc., etc.)

    Transition points can easily be seen as points on the edge
    of chaotic boundarys of specific phase diagrams. In fact,
    they can be viewed as characteristic of many different types
    of phase changes...even the evolution of a massive star into
    a neutron star, or black hole, under the influence of
    gravity may be considered the same type process. Evolution
    and change...and then more evolution... Quite a beautiful
    universal process in a way, one which blends order,
    complexity, and chaos, all together. ...tonyC

    > --
    > __________
    > |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     


  2. Jim Menegay

    Jim Menegay Guest

    Tim Tyler <[email protected]> wrote in message news:<[email protected]>...
    > Jim Menegay <[email protected]> wrote or quoted:
    > > Tim Tyler <[email protected]> wrote in message
    > > news:<[email protected]>...
    > > > E.g. these days we know the patterns on zebras have at
    > > > least as much to do with reaction-diffusion
    > > > equations as they do with natural selection.
    > >
    > > Under which definition of complex/complexity do you
    > > think that zebra patterns are complex? [snip]
    >
    > Now you're trying to get me to give a binary definition of
    > complexity ;-)

    Actually, I was hoping that you would continue to adhere to
    Kolmogoroff, but back down from your claim that Zebra
    stripes are complex. After all, you do have a simulator of
    reaction-diffusion on your WEB site, which presumably can
    generate zebra striping patterns given a few simple
    parameter choices. The whole point of Kolmogoroff is to show
    that some things that naively seem complex when viewed
    descriptively are actually simple when viewed as the output
    of an algorithm.
     
  3. Guy Hoelzer

    Guy Hoelzer Guest

    in article [email protected], Jim Menegay at
    [email protected] wrote on 4/30/04 8:14 AM:

    > Tim Tyler <[email protected]> wrote in message
    > news:<[email protected]>...
    >> TV-screen static has very large Kolmogorov complexity -
    >> but shows not the slighest hint of self-organising
    >> processes.
    >
    > I'm not disagreeing, exactly, but I can't resist pointing
    > out that your example suggests yet another ambiguity in
    > the concept of complexity. Wolfram's book contains many
    > pictures of something that looks a lot like TV static that
    > were generated by very simple algorithms. That is very low
    > Kolmogorov complexity.

    This is a great point. I hate to do this, but, I want to
    argue that these relations are more complicated that
    suggested here. It is a central observation in the
    complexity literature that simple rules at one scale of
    organization can lead to unforeseen (some argue
    unforeseeable in principle, but I disagree) emergence of
    structure/process at large scales of organization. How all
    of this related to Kolmogorov complexity (KC) depends on
    what aspects of the system you are measuring. Jim focused on
    the simple rules, which do not change in this scenario.
    Hence, KC for the system does not evolve from this point of
    view. If, however, you measure KC using data on the
    structure of the system, then it can and does evolve. In
    fact, it changes suddenly and coincidently with the
    emergence of higher order structure/function. I can't recall
    at the moment whether the structural KC jumps up or down
    when emergence occurs.

    > I understand that your point was that a particular
    > instance of TV static probably cannot be generated by a
    > simple algorithm. But then, who is interested in the
    > complexity of a particular instance?
    >
    > Second (hopably amusing) point: Ever wonder what happens
    > if you point a video camera at a TV screen which is being
    > fed from the camera? I have seen it claimed that
    > (depending on the zoom) this is an example of self
    > organization.

    Interesting. This seems to set up a visual analog to
    feedback in a sound system, which manifests when you point a
    microphone at a speaker. I often use auditory feedback as an
    example of natural selection in an abiotic system, and I see
    natural selection as a mechanism of self-organization; so
    your suggestion makes perfect sense to me.

    Guy
     
  4. Guy Hoelzer

    Guy Hoelzer Guest

    Hi Jim,

    in article [email protected], Jim Menegay at
    [email protected] wrote on 4/30/04 8:14 AM:

    > Guy Hoelzer <[email protected]> wrote in message
    > news:<[email protected]>...
    >> in article [email protected], Jim Menegay
    >> at [email protected] wrote on 4/28/04 2:44 PM:
    >>
    >>> Guy Hoelzer <[email protected]> wrote in message
    >>> news:<[email protected]>...
    >>>> While you and I come to different conclusions, or
    >>>> speculations, on the prospects for a coherent theory of
    >>>> complex systems, I agree with you that there are some
    >>>> key conceptual links that must be hammered out before
    >>>> complexity theory should become taken for granted.
    >>>> AFAIK nobody has yet proven (or argued convincingly)
    >>>> that there is a consistent set of necessary and
    >>>> sufficient conditions for the emergence of complexity.
    >>>
    >>> IMO, no one has given a sufficiently clear definition of
    >>> either "emergence" or "complexity" so that it even makes
    >>> sense to talk about necessary and sufficient conditions.
    >>
    >> I disagree. I suspect that the confusion resides more in
    >> your mind than in scientific communication within the
    >> complexity community. I don't mean this as an insult. It
    >> is our responsibility to make these terms clear to those
    >> who see their meanings as vague.
    >
    > Here is a resource regarding some of the meanings of
    > "complexity" as used within the scientific community.
    > http://www.santafe.edu/projects/CompMech/tutorials/Comp-
    > lexityMeasures.pdf I think that each of these meanings
    > has been adequately made clear. What has not been made
    > clear on this thread is which of these meanings the
    > poster is using.

    That link appears to be dead at this point, but I think I
    tracked it down under a new URL at SFI. If I found the right
    page, it was written by Murray Gell-Mann and Jim
    Crutchfield, and it was more about the diversity of proposed
    measures of complexity than about the concept itself. In
    support of my comment, I did not have much difficulty in
    speaking with Gell-Mann about complexity during my
    sabbatical at SFI. On the other hand, I found that
    Crutchfield was less comfortable talking about the concept
    without specifying a particular measure.

    >>> For example, you are now using "emergence" in a sense
    >>> which is totally different from the sense in which I had
    >>> paraphrased Bar-Lev as using it as the distinguishing
    >>> characteristic of a complex system.
    >>
    >> I presume you meant "Yaneer Bar-Yam", rather than
    >> Bar-Lev.
    > You are right, of course. My mistake.
    >> I have know Yaneer for years, and our views and semantics
    >> are very closely aligned on these issues. Again, your
    >> suspicion that we are at odds seems to result from a
    >> combination of our lack of precision in describing our
    >> views and the way you perceive our descriptions.
    >
    > No, it was my lack of precision that caused you to suspect
    > that I suspect... I was not accusing you of using
    > "emergence" incorrectly. I was just pointing out that
    > there are two meanings to the word.
    >
    >>> You seem to be using "emergence" to mean a process of
    >>> change occuring in time.
    >>
    >> Yes. Emergence is a process and all processes
    >> fundamentally depend on the temporal dimension.
    >>
    >>> But I was using it to describe a relationship between
    >>> the descriptive properties of a system and the
    >>> descriptive properties of its subsystems.
    >>
    >> This is closer to the meaning of complexity, although it
    >> lacks the critical aspect of interaction structure among
    >> the parts defining the topology of the network.
    >
    > Yes. Bar Yam defines a "complex system" as one which has
    > "emergent properties". And, if you check the Wilkipedia
    > article on "emergence" you will discover that you are
    > directed to "emergent properties", but "emergence" is
    > defined as a process - as you would prefer.
    >>
    >>> Time does not appear at all in my sense of the word
    >>> "emergence", which is, I think, the standard one in this
    >>> context.
    >>
    >> I am certain that the standard use of emergence in this
    >> context requires a temporal dimension. I don't think that
    >> I have ever seen it used to represent a static pattern.
    >
    > Check this (another example appears below):
    > http://llk.media.mit.edu/projects/emergence/

    >From this website:
    "In this essay, we will explore the idea of emergence. We
    will examine how objects and patterns can arise from simple
    interactions in ways that are surprising and counter-
    intuitive."

    I think that they are also asserting the centrality of the
    temporal dimension in the notion of emergence.

    >>> If one wishes to study the "emergence" (your sense) of
    >>> "complex systems" (Bar-Lev's sense), then one is looking
    >>> at the emergence of emergence!
    >> [snip]
    >>> And, to add to the confusion, one must recognize that
    >>> there are two different ways that this can happen. The
    >>> obvious way is that the emergent property of the system
    >>> is a novelty - that property simply didn't exist before.
    >> [snip]
    >>> The less obvious way is that the property itself is not
    >>> new - the novelty is that this property becomes
    >>> classifiable as emergent.
    >>
    >> This implies a view that is strongly at odds with my
    >> understanding of complex systems. All properties of
    >> everything in the universe emerged. Can you give me an
    >> example of a property that you think did not come into
    >> existence in an emergent way? [snip]
    >
    > Sure. Have you perhaps noticed that some of the paragraphs
    > that I have written in this thread are "skeptical",
    > "sarcastic", or even "obnoxious"? You may have even
    > noticed that some of the sentences had these properties.
    > But I'll bet that you won't find any words with those
    > properties, and I'm sure I didn't type any letters or
    > punctuation marks with those properties. These are
    > emergent properties at the sentence level.

    Skepticism, sarcasm, and obnoxiousness are semantic
    properties for which all underlying structure resides in our
    brains. Our association of these properties with sentences
    does in fact emerge through the information processing in
    our brains.

    Still, I think I now see your point. I agree that emergence
    can be, and is, used variously in referring to qualities
    (properties), patterns, processes, and dissipative
    structure/processes. I also agree that this is unfortunate
    and should be made clear. Examples that I would use of
    quality emergence, the category in which I would put your
    example, include the observation that pressure cannot be
    defined for a single particle. It is a quality that can only
    be defined for a population of particles. In my view, the
    term "emergence" should not be used to describe this
    observation. It is a consequence of the way we conceptualize
    "pressure", rather than something that happens in a natural
    system. This confusion comes about in part from the fact
    that new qualities also emerge coincidentally with new
    structures/processes.

    > But note! I had the idea of being skeptical, sarcastic, or
    > obnoxious even before I broke my thought into sentences
    > and my sentences into words.
    >
    > If that example doesn't satisfy you, how about a
    > biological example. Imagine a species of prairie rodents
    > inhabiting the American Great Plains from Mexico to
    > Canada. Imagine that the average size varies with
    > latitude. In fact, a regression coefficient tieing the
    > latitude to the size of the rodent is a property of the
    > species. Now, imagine that the species breaks up into a
    > collection of distinct subspecies, perhaps due to the
    > construction of East-West highways. But within each
    > subspecies, there is not any correlation of latitude with
    > size. The regression of size against latitude has become
    > an emergent property. As I said:
    >>
    >>> This might happen because the system evolves so as to
    >>> become sufficiently differentiated that subsystems can
    >>> be recognized.
    >>>
    >>> My main point here is that sloppy use of terminology
    >>> leads to misleading intuitions.

    I may have lost the point of the thread here. I though we
    were focusing on whether emergence generally means a kind of
    process that must unfold over a window of time (my view).
    This example seems to fit nicely into my view. Are you
    implying that spatial clines and subspecies manifest
    instantly? I don't see how this example suggests either
    conceptual ambiguity or semantic inconsistency with regard
    to "complexity."

    >> As does "sloppy" listening.
    > Well, sloppy listening leads to misleading intuitions only
    > if one believes what one hears. I rarely do that ;-)

    I didn't mean to suggest otherwise. I was only suggesting
    that you may be perceiving sloppiness in the use of the
    term "complexity" that does not exist so much among those
    using the term.

    >>> And, I think that the whole field of "complexity" is
    >>> plagued by bad choices of terminology and some very,
    >>> very bad intuitions. Furthermore, I don't see the
    >>> situation as likely to improve when books can be sold by
    >>> coining meaningless, but evocatative, phrases such as
    >>> "the edge of chaos". IMO.
    >>
    >> "Edge of chaos" is much more than a catchy phrase. Do you
    >> know what it means in this context?
    >
    > Yep! I know several things that it means. See my reply to
    > Wirt. Incidentally, I'm curious as to whether Wirt's
    > proposed meaning is the one you had in mind. When I
    > described this phrase as "meaningless", I had in mind the
    > fact that (like "complexity") it means different things
    > to different people. A word or phrase with too many
    > meanings is just as useless for scientific communication
    > as a word with no meanings. On the other hand, it IS
    > useful in poetry.

    I understand. This may be a case of a scientific phrase that
    is unfortunately poetic. Wirt's comments are entirely in
    line with my understanding of the phrase. I would add that I
    think Per Bak pushed the concept too far in the sense that
    complexity is not limited to systems that have reached the
    edge of chaos. Rather that seems to be the location in phase
    space that unconstrained complex systems tend to (sensu a
    strange attractor). I would point to the work of Carlson and
    Doyle on "highly optimized tolerance" for an example of
    rigorous modeling that illustrates the behavior of complex
    adaptive systems constrained away from the edge of chaos.

    > Incidentally, while preparing this post, I browsed the
    > website of the Santa Fe Institute and discovered some
    > quotes from a couple of biologists that I really respect.
    > I believe that I endorse their viewpoints regarding
    > "complexity" in general and the Santa Fe version of it in
    > particular.

    Me, too. I don't want to ask you for examples of those you
    don't "really respect", but I suspect that you would be
    blown away by the list of scientists involved with SFI. You
    might be interested in browsing at the following link:
    <http://www.santafe.edu/sfi/indexPeople.html>.

    > The first is from a review of a debate between Maynard
    > Smith and Kauffman:ttp://www.santafe.edu/sfi/publications/Bulletins/bulletin-
    > spr95/12debate.html
    >
    > Towards the end of question time, Maynard Smith suggested
    > that his real problem with a lot of complexity theory is
    > that it fails to ground itself in reality. Maynard Smith:
    > "My problem with Santa Fe, is that I can spend a whole
    > week there... and not hear a single fact." Kauffman: "Now
    > that's a fact!"

    Kauffman's name is closely tied to SFI in the minds of many,
    but the reality is that he hasn't spent much time there for
    several years. In fact, I would say that the views at SFI,
    in general, have diverged significantly from the ones that
    Kauffman advocates. Bak's claims for "the edge of chaos" are
    also viewed pretty skeptically by most scientists there.

    > The second quotes Robert May about SFI: http://www.sant-
    > afe.edu/sfi/publications/Bulletins/bulletinSummer01/fea-
    > tures/ma
    > y.html
    >
    > "The Institute was created as a better understanding of
    > the relation between simplicity and complexity in
    > nonlinear systems emerged," he says. "It saw itself as
    > maybe the place that could help articulate what replaces
    > the simplistic Newtonian dream. That was a pretty large
    > thing to take on: the boldness with which that vision has
    > been articulated has contributed to all the attention SFI
    > received." This attention tended to become polarized, he
    > says, between uncritical admiration on the one hand and
    > disparagement on the other, "neither of which reflects
    > the much more interesting and richly textured reality of
    > the place."
    >
    > So where does May stand? "I'm an enthusiast for the idea,"
    > he says, "but a rather analytic critic for what is an
    > accomplishment and what is charismatic blather."

    I looked over the SFI people website because I thought that
    May had developed an official relationship there. However, I
    did not find his name. I am certain, however, that he has
    been there a few times. My impression is that he shares the
    same perspective as the folks at SFI. This is the right
    direction, and we need to maintain a balance between rigor
    and creativity if we are to succeed in establishing
    complexity science (if that is a reasonable term).

    Guy
     
  5. Tim Tyler

    Tim Tyler Guest

    Jim Menegay <[email protected]> wrote or quoted:
    > Tim Tyler <[email protected]> wrote in message
    > news:<[email protected]>...

    > > TV-screen static has very large Kolmogorov complexity -
    > > but shows not the slighest hint of self-organising
    > > processes.
    >
    > I'm not disagreeing, exactly, but I can't resist pointing
    > out that your example suggests yet another ambiguity in
    > the concept of complexity. Wolfram's book contains many
    > pictures of something that looks a lot like TV static that
    > were generated by very simple algorithms. That is very low
    > Kolmogorov complexity.
    >
    > I understand that your point was that a particular
    > instance of TV static probably cannot be generated by a
    > simple algorithm. But then, who is interested in the
    > complexity of a particular instance?

    I used TV static as an example of a random process.

    Not just particular instances are very noisy - so is the
    whole stream.

    If you don't like the example, pick another process with a
    heavy random element. Radioactive decay, for example. Or
    diffusion of gas particles. Or thermal noise. Or the way
    raindrops hit the street...

    > Second (hopably amusing) point: Ever wonder what happens
    > if you point a video camera at a TV screen which is being
    > fed from the camera? I have seen it claimed that
    > (depending on the zoom) this is an example of self
    > organization.

    Like most Dr Who fans, I don't have to wonder - and indeed
    (also probably like most Dr Who fans) I have performed the
    experiment in person ;-)
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  6. Tim Tyler

    Tim Tyler Guest

    Jim Menegay <[email protected]> wrote or quoted:
    > Tim Tyler <[email protected]> wrote in message
    > news:<[email protected]>...
    > > Jim Menegay <[email protected]> wrote or quoted:
    > > > Tim Tyler <[email protected]> wrote in message
    > > > news:<[email protected]>...

    > > > > E.g. these days we know the patterns on zebras have
    > > > > at least as much to do with reaction-diffusion
    > > > > equations as they do with natural selection.
    > > >
    > > > Under which definition of complex/complexity do you
    > > > think that zebra patterns are complex? [snip]
    > >
    > > Now you're trying to get me to give a binary definition
    > > of complexity ;-)
    >
    > Actually, I was hoping that you would continue to adhere
    > to Kolmogoroff,

    OK - let's pretend for a moment that I did that ;-)

    > but back down from your claim that Zebra stripes are
    > complex. After all, you do have a simulator of reaction-
    > diffusion on your WEB site, which presumably can generate
    > zebra striping patterns given a few simple parameter
    > choices. [...]

    Yes - but although you *can* produce striped patterns from a
    few simple parameters, the *actual* pattern produced depends
    on the entire initial state of the reaction-diffusion system
    in addition.

    In other words, faced with a particular zebra, to reproduce
    the patterns on it might need a fairly detailed description
    of the initial state of the system - as well as just the reaction-
    diffusion parameters.

    You could create a broadly-similar looking zebra from a
    simple ordered set of starting conditions - but if we are
    using Kolmogoroff complexity, we are (presumably) working in
    a discrete domain and we need to reproduce the pattern we
    are measuring exactly.

    > The whole point of Kolmogoroff is to show that some things
    > that naively seem complex when viewed descriptively are
    > actually simple when viewed as the output of an algorithm.

    I'd say reaction-diffusion patterns are somewhat
    intermediate between (say) Mandelbrots (highly ordered) and
    noise (highly disordered) in that respect.

    Some have simple descriptions, but others may only arise
    from starting conditions of the fluid fields that are rather
    laborious to specify.

    I'll grant that many zebra patterns have considerable
    regularity and "compressiblilty" - and thus may not be as
    complex as all that.

    We can't really use Kolmogoroff complexity as a metric for
    zebra stripes, though. Zebra stripes are not digital.

    Kolmogorov complexity in biology works best on things that
    are discrete (or nearly so) e.g. the genetic program (give
    or take a bit of methylation).
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
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  7. Guy Hoelzer

    Guy Hoelzer Guest

    Tim,

    in article [email protected], Tim Tyler at
    [email protected] wrote on 4/30/04 8:14 AM:

    > Guy Hoelzer <[email protected]> wrote or quoted:
    >> in article [email protected], Tim Tyler
    >> at [email protected]
    >>> Guy Hoelzer <[email protected]> wrote or quoted:
    >>>> Tim Tyler at [email protected] wrote on 4/27/04 2:32 PM:
    >
    >>>>> If biological relevance is your criterion, "self-
    >>>>> organising systems" are the main bit of "complexity
    >>>>> theory" of interest.
    >>>>>
    >>>>> They present alternative explanations for the
    >>>>> existence of complex structures to natural selection.
    >>>>
    >>>> No, no, no! This is a nasty misconception, which is
    >>>> causing knee-jerk dismissal of complexity theory among
    >>>> many evolutionary biologists. Natural selection IS a
    >>>> mechanism of self-organization. I agree that there are
    >>>> other mechanisms of self-organization that are
    >>>> important in biology, but it is misleading to imply
    >>>> that natural selection somehow represents an
    >>>> explanation that is mutually exclusive to self-
    >>>> organization.
    >>>
    >>> I don't think I said what you seem to think I did.
    >>>
    >>> I agree that natural selection IS a mechanism of self-
    >>> organization.
    >>>
    >>> I agree that there are other mechanisms of self-
    >>> organization that may be significant in biology.
    >>>
    >>> I fail to see much sign of any disagreement that might
    >>> have prompted the "No, no, no!"
    >>>
    >>> *If* I had claimed that natural selection and self-
    >>> organization were mutually exclusive you would have a
    >>> point - but I never said any such thing.
    >>
    >> Thanks for clearing this up. I'm sorry for my over-
    >> reaction.
    >>
    >> I have found that most evolutionary biologists that I
    >> talk to have the kind of misconception I described above.
    >> While I am glad that we actually share a common
    >> understanding on these issues, I am pretty sure that most
    >> evolutionary biologists would interpret the statement
    >> "They [self-organizing systems] present alternative
    >> explanations for the existence of complex structures to
    >> natural selection" as a confrontation to Darwinism. I
    >> think we should strive for clarity that avoids this kind
    >> of misinterpretation.
    >
    > "Self-organisation" /is/ in conflict with what is
    > characatured as "panadaptionism" - the idea that most
    > prominent features of organisms exist because they are
    > favoured by selection.

    Sure. I would argue that this idea is itself at odds with
    what Darwin wrote. It is an oversimplified cartoon.

    > There are other self-organising forces *besides* natural
    > selection.

    Yes.

    > They are responsible for things like animal patterning,
    > tree-shaped structures, drainage patterns and the
    > development of the brain.

    Sure, but this concept is also not an alternative to natural
    selection. In fact, as several authors have pointed out
    (e.g., see Camazine et al., "Self-organization in biological
    systems), natural selection should generally favor the
    efficiency afforded to genetic encoding of the phenotype by
    using simple rules to manifest macroscopic patterns.

    > Natural selection may get the final say - but the
    > generation of variation /often/ involves alternatives that
    > can be easily produced.
    >
    > It may be quite reasonable to say that a branching tree
    > was one of the early variations formed - because there was
    > a short sequence of developmental instructions that led to
    > it and the sequence could easily be reached by mutation.
    >
    > The idea that simple instruction sequences produce apparently-
    > complex, patterened and purposeful-looking results is well
    > known to those interested in fractals and cellular
    > automata.

    I agree with all of this, and I fail to see how it is in
    conflict even with "panadaptationism."

    > It may be that processes like those play significant roles
    > in development - and that those are the processes we
    > should invoke as primary explanations for the observed
    > phenomena (rather than saying natural selection is
    > responsible).

    Or we can recognize the absence of conflict among these
    ideas and attribute responsibility to all of them
    simultaneously. This approach is routine under the logic of
    hierarchical systems, but anathema to the more linear,
    traditional framework for scientific thought.

    > Wolfram probably takes this "anti-selectionism" the
    > furthest:
    >
    > ``For while natural selection is often touted as a force
    > of almost arbitrary power, I have increasingly come to
    > believe that in fact its power is remarkably limited.''

    Yeah. He also takes the right path without stopping before
    going off the deep end, IMHO. I've actually seen more
    extreme statements (e.g., a paper by Emlen et al. from about
    1994 published in Chaos), but I can't put my hands on them
    right now. Such logically misinformed and over the top
    statements have done a lot of harm IMHO.

    Guy
     
  8. Tim Tyler <[email protected]> wrote in
    news:[email protected]:

    > There are other self-organising forces *besides* natural
    > selection. They are responsible for things like animal
    > patterning, tree-shaped structures, drainage patterns and
    > the development of the brain.

    I agree.

    > Natural selection may get the final say - but the
    > generation of variation /often/ involves alternatives that
    > can be easily produced.

    (snip)

    > It may be that processes like those play significant roles
    > in development - and that those are the processes we
    > should invoke as primary explanations for the observed
    > phenomena (rather than saying natural selection is
    > responsible).

    Why should the fact that evolution is constrained by physics
    imply that we should invoke physics as a "primary
    explanation"?

    > Wolfram probably takes this "anti-selectionism" the
    > furthest:
    >
    > ``For while natural selection is often touted as a force
    > of almost arbitrary power, I have increasingly come to
    > believe that in fact its power is remarkably limited.''
    >
    > - S.W. A.N.K.O.S., p.392.

    This statement seems to me to miss the mark on the nature of
    natural selection. Natural selection is not important
    because of its power, but because of its single-mindedness.
    It doesn't need to have much power, it only needs to have
    time. As long as the basic conditions hold, you can only get
    improvement. Now you can not tell how much improvement - the
    power is not in fact "arbitrary". The question of how much
    improvement is more dependent on historical factors such as
    drift and physical and chemical constraints. That is not the
    point. The point is to build on previous success.

    Yours,

    Bill Morse
     
  9. Tim Tyler

    Tim Tyler Guest

    William Morse <[email protected]> wrote or quoted:
    > Tim Tyler <[email protected]> wrote in
    > > Guy Hoelzer <[email protected]> wrote or quoted:
    > >> Tim Tyler at [email protected]

    > >> > Natural selection may get the final say - but the
    > >> > generation of variation /often/ involves alternatives
    > >> > that can be easily produced.
    >
    > >> > It may be quite reasonable to say that a branching
    > >> > tree was one of the early variations formed - because
    > >> > there was a short sequence of developmental
    > >> > instructions that led to it and the sequence could
    > >> > easily be reached by mutation.
    >
    > >> > The idea that simple instruction sequences produce
    > >> > apparently- complex, patterened and purposeful-
    > >> > looking results is well known to those interested in
    > >> > fractals and cellular automata.
    >
    > >> I agree with all of this, and I fail to see how it is
    > >> in conflict even with "panadaptationism."
    >
    > > The characature of a panadaptationist will tend to look
    > > at the order created by a self-organising system and
    > > tend to invent adaptive explanations for the existence
    > > of that order.
    >
    > > E.g. rather than answering the question of why legs of a
    > > centipede are all the same by invoking the fact
    > > that they are all generated by the same small
    > > simple program, the panadaptationist will tend to
    > > suggest that centipede legs are all the same so
    > > that each leg fits in exactly with the stride of
    > > the leg in front of it - and no toes get stepped
    > > on.
    >
    > > Explanations in terms of small developmental programs
    > > don't occur to our characatured panadaptationist -
    > > because he thinks that natural selection is the answer
    > > to all biological problems involving structure and form.
    >
    > But - to play devil's advocate, because I tend to agree
    > with you - what if our caricatured (to keep Josh happy
    > note the spelling) panadaptationist were to say that the
    > developmental genes that led to segmentation got
    > selected over other alternatives during the Cambrian
    > explosion precisely because they made it easier for
    > coordinated motion?

    In my example, the caricatured panadaptationist's argument
    certainly has some truth to it. If legs of differing - or
    alternating - shape proved to be adaptive, then maybe nature
    would have discovered the fact by now.

    ...but the form of the argument is not always right:

    Natural selection based on the phenotype - and the founder
    effect - are not the only valid forms of explanation for
    observed traits.

    Sometimes it is best to look at the form of the genetic
    program that results in the feature - and ask how simple,
    neat, flexible and maintainable it is - and how likely it
    was to have been chanced upon by mutations - and produce
    that as your explanation.

    Of course there are many other things going on as well in
    nature. For instance, something designed for one purpose
    often turn out to have other uses. My computer makes a
    workable doorstop. A letter box can be used to view
    prospective visitors on the doorstop.

    Gould give the example of flight to illustrate this point:

    http://www.stephenjaygould.org/library/gould_functional-
    shift.html
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  10. Tim Tyler

    Tim Tyler Guest

    William Morse <[email protected]> wrote or quoted:
    > Tim Tyler <[email protected]> wrote in

    > > It may be that processes like those play significant
    > > roles in development - and that those are the processes
    > > we should invoke as primary explanations for the
    > > observed phenomena (rather than saying natural selection
    > > is responsible).
    >
    > Why should the fact that evolution is constrained by
    > physics imply that we should invoke physics as a "primary
    > explanation"?

    Sorry if my statement was unclear. I meant this only in some
    cases. In other cases natural selection will be the primary
    explanation. In yet other cases it may be necessary to
    invoke the founder effect as the main cause of certain
    phenomena.

    > > Wolfram probably takes this "anti-selectionism" the
    > > furthest:
    > >
    > > ``For while natural selection is often touted as a force
    > > of almost arbitrary power, I have increasingly come to
    > > believe that in fact its power is remarkably limited.''
    > >
    > > - S.W. A.N.K.O.S., p.392.
    >
    > This statement seems to me to miss the mark on the nature
    > of natural selection. Natural selection is not important
    > because of its power, but because of its single-
    > mindedness. It doesn't need to have much power, it only
    > needs to have time. [...]

    I'm probably guilty of quoting Wolfram out of context.
    Picking one of his more extreme sentences may give a
    distorted impression of his argument - which is generally
    not an unreasonable one.

    Certainly I share many of Wolfram's intuitions about not
    even the billions of years available being enough for
    natural selection to be able to "design" very much in the
    way of complex systems - and since self-organising systems -
    of the type that can arise from short and simple
    developmental programs - generate ordered complex structures
    in great abundance, they are a natural explanation for much
    of the observed complexity in nature.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  11. Jim Menegay

    Jim Menegay Guest

    Guy Hoelzer <[email protected]> wrote in message news:<[email protected]>...
    > in article [email protected], Jim Menegay
    > at [email protected] wrote on 4/30/04 8:14 AM:

    Responding to just a few scattered points:

    > > Here is a resource regarding some of the meanings of
    > > "complexity" as used within the scientific community.
    > > http://www.santafe.edu/projects/CompMech/tutorials/Comp-
    > > lexityMeasures.pdf I think that each of these meanings
    > > has been adequately made clear. What has not been made
    > > clear on this thread is which of these meanings the
    > > poster is using.
    >
    > That link appears to be dead at this point, but I think I
    > tracked it down under a new URL at SFI. If I found the
    > right page, it was written by Murray Gell-Mann and Jim
    > Crutchfield, and it was more about the diversity of
    > proposed measures of complexity than about the concept
    > itself. In support of my comment, I did not have much
    > difficulty in speaking with Gell-Mann about complexity
    > during my sabbatical at SFI. On the other hand, I found
    > that Crutchfield was less comfortable talking about the
    > concept without specifying a particular measure.

    My apologies. I keep forgetting that not everyone can browse
    to .pdf files. For your future convenience, may I suggest
    that a good thing to do when a pdf link is provided that you
    cannot read, try moving up one level in the URL - in this
    case to: http://www.santafe.edu/projects/CompMech/tutorials/
    Had you done so, you would have found both pdf and
    postscript links to the paper I was suggesting. However, I
    am glad that you did not know this, because it gave you the
    opportunity to tell me how easy it is to talk to Murray.

    > [regarding "emergence" and "emergent properties"] Examples
    > that I would use of quality emergence, the category in
    > which I would put your example, include the observation
    > that pressure cannot be defined for a single particle. It
    > is a quality that can only be defined for a population of
    > particles. In my view, the term "emergence" should not be
    > used to describe this observation. It is a consequence of
    > the way we conceptualize "pressure", rather than something
    > that happens in a natural system. This confusion comes
    > about in part from the fact that new qualities also emerge
    > coincidentally with new structures/processes.

    Your suggestion that "emergence" should not be used in an
    epistemological sense, but only in a physical sense, is
    understandable. After all, the nontechnical uses of the word
    convey the notion of a physical process occuring in time.
    However, you should be aware that the epistemological
    technical use of the word has a long history: http://plato.stanford.edu/entries/properties-
    emergent/ But more relevant to the present discussion is the
    use of the word as a slogan by "General Systems Theory".
    This was an interesting intellectual movement, better known
    in the past generation, from which the modern "complexity"
    movement has inherited terminology, aura, and stigma. The
    main gurus were von Bertalanfy, Boulding, and Koestler.
    These authors based much of their anti-reductionist stance
    on the observation that, as a system is synthesized in a "bottom-
    up" direction, new properties "emerge" at the higher levels.
    The whole is more than the sum of its parts. A "holistic"
    viewpoint is needed. Or, saying the same thing, as a system
    is analyzed in a "top-down" direction, something is lost.
    Hence, reductionism is suspect, according to GST.

    > > Imagine a species of prairie rodents inhabiting the
    > > American Great Plains from Mexico to Canada. Imagine
    > > that the average size varies with latitude. In fact, a
    > > regression coefficient tieing the latitude to the size
    > > of the rodent is a property of the species. Now, imagine
    > > that the species breaks up into a collection of distinct
    > > subspecies, perhaps due to the construction of East-West
    > > highways. But within each subspecies, there is not any
    > > correlation of latitude with size. The regression of
    > > size against latitude has become an emergent property.
    > > As I said:
    > >>
    > >>> This might happen because the system evolves so as to
    > >>> become sufficiently differentiated that subsystems can
    > >>> be recognized.
    >
    > I may have lost the point of the thread here. I though we
    > were focusing on whether emergence generally means a kind
    > of process that must unfold over a window of time (my
    > view). This example seems to fit nicely into my view.

    I thought we had moved beyond that focus, though, looking
    back through the thread, I can see that I was incorrect.
    Several posts ago, I suggested that there are two different
    ways in which epistemological emergence (non-process sense)
    could emerge (in the process sense). My example was intended
    to illustrate the less obvious of the two ways. However, the
    point that I am making is not a particularly important one,
    and I am happpy to drop the issue.
     
  12. Tim Tyler

    Tim Tyler Guest

    Guy Hoelzer <[email protected]> wrote or quoted:
    > in article [email protected], Tim Tyler at
    > [email protected]

    > > Natural selection may get the final say - but the
    > > generation of variation /often/ involves alternatives
    > > that can be easily produced.
    > >
    > > It may be quite reasonable to say that a branching tree
    > > was one of the early variations formed - because there
    > > was a short sequence of developmental instructions that
    > > led to it and the sequence could easily be reached by
    > > mutation.
    > >
    > > The idea that simple instruction sequences produce apparently-
    > > complex, patterened and purposeful-looking results is
    > > well known to those interested in fractals and cellular
    > > automata.
    >
    > I agree with all of this, and I fail to see how it is in
    > conflict even with "panadaptationism."

    The characature of a panadaptationist will tend to look
    at the order created by a self-organising system and
    tend to invent adaptive explanations for the existence
    of that order.

    E.g. rather than answering the question of why legs of a
    centipede are all the same by invoking the fact that
    they are all generated by the same small simple
    program, the panadaptationist will tend to suggest that
    centipede legs are all the same so that each leg fits
    in exactly with the stride of the leg in front of it -
    and no toes get stepped on.

    Explanations in terms of small developmental programs don't
    occur to our characatured panadaptationist - because he
    thinks that natural selection is the answer to all
    biological problems involving structure and form.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  13. Guy Hoelzer

    Guy Hoelzer Guest

    Hi Bill,

    Note that I have snipped one sentence out of a longer post.

    in article [email protected], William Morse
    at [email protected] wrote on 5/1/04 7:32 PM:

    > Why should the fact that evolution is constrained by
    > physics imply that we should invoke physics as a "primary
    > explanation"?

    Good question. Physical constraints alone do not build an
    engine of work like life. They are not enough, which is why
    many folks, including myself, are now calling for a re-
    evaluation of the thermodynamic laws (either a modification
    of the second law, or the addition of a fourth law). We are
    striving to put the "dynamics" into the laws of
    thermodynamics. The traditional understanding of the second
    law as a "ONE WAY" traffic sign is only a constraint. It
    does not make anything go that way.

    Setting aside the potential for an improved understanding of
    physical dynamics, your question seems to imply that biology
    is somehow more than just its physical underpinnings. I am
    curious as to just what it is that you think it is about
    biology that is not physical. Is there biological
    metaphysics? If so, isn't the science of biology doomed due
    to the absence of rules that we can know of governing
    metaphysics?

    Cheers,

    Guy
     
  14. Guy Hoelzer

    Guy Hoelzer Guest

    in article [email protected], Jim Menegay at
    [email protected] wrote on 5/2/04 2:04 PM:

    > Guy Hoelzer <[email protected]> wrote in message
    > news:<[email protected]>...
    [snip]
    >> [regarding "emergence" and "emergent properties"]
    >> Examples that I would use of quality emergence, the
    >> category in which I would put your example, include the
    >> observation that pressure cannot be defined for a single
    >> particle. It is a quality that can only be defined for a
    >> population of particles. In my view, the term "emergence"
    >> should not be used to describe this observation. It is a
    >> consequence of the way we conceptualize "pressure",
    >> rather than something that happens in a natural system.
    >> This confusion comes about in part from the fact that new
    >> qualities also emerge coincidentally with new
    >> structures/processes.
    >
    > Your suggestion that "emergence" should not be used in an
    > epistemological sense, but only in a physical sense, is
    > understandable. After all, the nontechnical uses of the
    > word convey the notion of a physical process occuring in
    > time. However, you should be aware that the
    > epistemological technical use of the word has a long
    > history: http://plato.stanford.edu/entries/properties-
    > emergent/ But more relevant to the present discussion is
    > the use of the word as a slogan by "General Systems
    > Theory". This was an interesting intellectual movement,
    > better known in the past generation, from which the modern
    > "complexity" movement has inherited terminology, aura, and
    > stigma. The main gurus were von Bertalanfy, Boulding, and
    > Koestler. These authors based much of their anti-
    > reductionist stance on the observation that, as a system
    > is synthesized in a "bottom-up" direction, new properties
    > "emerge" at the higher levels. The whole is more than the
    > sum of its parts. A "holistic" viewpoint is needed. Or,
    > saying the same thing, as a system is analyzed in a "top-
    > down" direction, something is lost. Hence, reductionism is
    > suspect, according to GST.

    It seems we agree. In fact, I have toyed with the idea of
    writing a book on complexity and some of the chapters I have
    outlined deal specifically with emergent properties
    (qualities), emergent structures, and emergent functions,
    respectively. I don't know whether I will ever take a
    serious shot at finishing this book, but a central
    conclusion I would reach regards the fundamental importance
    of emergent entities (coherent agents of action and effect).
    My goal would be in part to disentangle the physical aspects
    of emergence from our mere perceptions of emergence (e.g.,
    surprise at the possibility of new qualities as population
    size changes).

    [snip]

    Regards,

    Guy
     
  15. Tim Tyler <[email protected]> wrote in
    news:[email protected]:

    > Guy Hoelzer <[email protected]> wrote or quoted:
    >> in article [email protected], Tim Tyler at
    >> [email protected]

    >> > Natural selection may get the final say - but the
    >> > generation of variation /often/ involves alternatives
    >> > that can be easily produced.

    >> > It may be quite reasonable to say that a branching tree
    >> > was one of the early variations formed - because there
    >> > was a short sequence of developmental instructions that
    >> > led to it and the sequence could easily be reached by
    >> > mutation.

    >> > The idea that simple instruction sequences produce apparently-
    >> > complex, patterened and purposeful-looking results is
    >> > well known to those interested in fractals and cellular
    >> > automata.

    >> I agree with all of this, and I fail to see how it is in
    >> conflict even with "panadaptationism."

    > The characature of a panadaptationist will tend to look
    > at the order created by a self-organising system and
    > tend to invent adaptive explanations for the existence
    > of that order.

    > E.g. rather than answering the question of why legs of a
    > centipede are all the same by invoking the fact that
    > they are all generated by the same small simple
    > program, the panadaptationist will tend to suggest
    > that centipede legs are all the same so that each leg
    > fits in exactly with the stride of the leg in front
    > of it - and no toes get stepped on.

    > Explanations in terms of small developmental programs
    > don't occur to our characatured panadaptationist - because
    > he thinks that natural selection is the answer to all
    > biological problems involving structure and form.

    But - to play devil's advocate, because I tend to agree
    with you - what if our caricatured (to keep Josh happy
    note the spelling) panadaptationist were to say that the
    developmental genes that led to segmentation got
    selected over other alternatives during the Cambrian
    explosion precisely because they made it easier for
    coordinated motion?

    Yours,

    Bill Morse
     
  16. John Wilkins

    John Wilkins Guest

    Guy Hoelzer <[email protected]> wrote:

    > in article [email protected], Jim Menegay
    > at [email protected] wrote on 5/2/04 2:04 PM:
    >
    > > Guy Hoelzer <[email protected]> wrote in message
    > > news:<[email protected]>...
    > [snip]
    > >> [regarding "emergence" and "emergent properties"]
    > >> Examples that I would use of quality emergence, the
    > >> category in which I would put your example, include the
    > >> observation that pressure cannot be defined for a
    > >> single particle. It is a quality that can only be
    > >> defined for a population of particles. In my view, the
    > >> term "emergence" should not be used to describe this
    > >> observation. It is a consequence of the way we
    > >> conceptualize "pressure", rather than something that
    > >> happens in a natural system. This confusion comes about
    > >> in part from the fact that new qualities also emerge
    > >> coincidentally with new structures/processes.
    > >
    > > Your suggestion that "emergence" should not be used in
    > > an epistemological sense, but only in a physical
    > > sense, is understandable. After all, the nontechnical
    > > uses of the word convey the notion of a physical
    > > process occuring in time. However, you should be aware
    > > that the epistemological technical use of the word has
    > > a long history: http://plato.stanford.edu/entries/properties-
    > > emergent/ But more relevant to the present discussion
    > > is the use of the word as a slogan by "General Systems
    > > Theory". This was an interesting intellectual
    > > movement, better known in the past generation, from
    > > which the modern "complexity" movement has inherited
    > > terminology, aura, and stigma. The main gurus were von
    > > Bertalanfy, Boulding, and Koestler. These authors
    > > based much of their anti-reductionist stance on the
    > > observation that, as a system is synthesized in a "bottom-
    > > up" direction, new properties "emerge" at the higher
    > > levels. The whole is more than the sum of its parts. A
    > > "holistic" viewpoint is needed. Or, saying the same
    > > thing, as a system is analyzed in a "top-down"
    > > direction, something is lost. Hence, reductionism is
    > > suspect, according to GST.
    >
    > It seems we agree. In fact, I have toyed with the idea of
    > writing a book on complexity and some of the chapters I
    > have outlined deal specifically with emergent properties
    > (qualities), emergent structures, and emergent functions,
    > respectively. I don't know whether I will ever take a
    > serious shot at finishing this book, but a central
    > conclusion I would reach regards the fundamental
    > importance of emergent entities (coherent agents of action
    > and effect). My goal would be in part to disentangle the
    > physical aspects of emergence from our mere perceptions of
    > emergence (e.g., surprise at the possibility of new
    > qualities as population size changes).
    >
    > [snip]
    >
    >
    > Regards,
    >
    > Guy

    I strongly recommend this book:

    Blitz, David. 1992. Emergent evolution: qualitative novelty
    and the levels of reality. Dordrecht; Boston: Kluwer
    Academic Publishers.

    and the *term* is, I believe, due to this one:

    Morgan, Conwy Lloyd. 1923. Emergent evolution : the Gifford
    lectures delivered in the University of St. Andrews in the
    year 1922, Gifford Lectures. St. Andrews University ; 1922.
    London: Williams And Norgate.

    although the *idea* goes back to Mill.
    --
    Dr John S. Wilkins, www.wilkins.id.au "I never meet anyone
    who is not perplexed what to do with their children" --
    Charles Darwin to Syms Covington, February 22, 1857
     
  17. Guy Hoelzer <[email protected]> wrote in
    news:[email protected]:

    > Note that I have snipped one sentence out of a
    > longer post.
    >
    > in article [email protected], William
    > Morse at [email protected] wrote on 5/1/04 7:32 PM:
    >
    >> Why should the fact that evolution is constrained by
    >> physics imply that we should invoke physics as a "primary
    >> explanation"?

    > Good question. Physical constraints alone do not build an
    > engine of work like life. They are not enough, which is
    > why many folks, including myself, are now calling for a
    > re-evaluation of the thermodynamic laws (either a
    > modification of the second law, or the addition of a
    > fourth law). We are striving to put the "dynamics" into
    > the laws of thermodynamics. The traditional understanding
    > of the second law as a "ONE WAY" traffic sign is only a
    > constraint. It does not make anything go that way.
    >
    > Setting aside the potential for an improved understanding
    > of physical dynamics, your question seems to imply that
    > biology is somehow more than just its physical
    > underpinnings. I am curious as to just what it is that you
    > think it is about biology that is not physical. Is there
    > biological metaphysics? If so, isn't the science of
    > biology doomed due to the absence of rules that we can
    > know of governing metaphysics?

    Dang! Now I have to try to remember what I was thinking when
    I made that statment :)

    But before I do that: isn't the science of physics doomed
    due to the absence of rules that we can know of governing
    metaphysics? Assuming a reductionist stance for now - that
    biology is explained by chemistry, and chemistry is
    explained by physics - then I have to ask the question: what
    explains physics? Is there physical metaphysics? There
    appear to be three possible answers - probably Dr. John
    (Wilkins) can come up with more:

    (1) the cosmological argument is correct, and there is a
    prime mover somewhere who decreed what the speed of
    light would be, and what Planck's constant would be,
    etc., etc.;

    (2) there is an infinite chain of regression, and we will
    always find a further reductionist reason for the reason
    (protons are explained by quarks, quarks are explained
    by string theory, string theory is explained by
    something we haven't come up with yet, etc. ad
    infinitum) I call this the turtle theory, after the joke
    about the world being held up by sitting on the back of
    a turtle - "but what holds up the turtle?" - "another
    turtle" - "but what holds up that turtle?"- "another
    turtle" - but what holds"- "give it up, kid, it's
    turtles all the way down"

    (3) the ontological argument is correct, and existence
    implies essence. I actually like this argument, at least
    compared to the alternatives, although I disagree with
    St. Anselm that it proves the existence of a Supreme
    Being. It seems possible to me that if you have
    existence, then you must have non-existence, so you have
    a 0 and a 1. Given a 0 and a 1 you can construct binary
    mathematics, and from that you can construct mathematics
    in general. Now I have no idea how you get from that to
    Planck's constant, but that's just a minor detail :)

    Having got that off my chest, my statement was really based
    on my interpreting "primary explanation" as more akin to
    final cause than formal cause.The mackerel has a deeply
    forked tail because fluid dynamics dictates that as the best
    shape for high speed swimming in water if maneuverability is
    less important, but the reason that a mackerel needs to swim
    fast with limited maneuverability is related to selection
    for its niche.

    I do believe that in some cases it is appropriate to invoke
    physics or chemistry as a primary explanation. For instance,
    I would argue that most animals are bilaterally symmetrical
    because of chemical constraints on development, not because
    of selective bias for that form. I was mostly arguing
    against taking this to the extreme position of using physics
    as the final cause for all of biology. While this may be
    true, it is probably unprovable and in any case is often of
    no help in our understanding.

    Yours,

    Bill Morse
     
  18. Guy Hoelzer

    Guy Hoelzer Guest

    in article [email protected], William Morse at
    [email protected] wrote on 5/6/04 4:44 PM:

    > Guy Hoelzer <[email protected]> wrote in
    > news:[email protected]:
    >
    >
    >> Note that I have snipped one sentence out of a
    >> longer post.
    >>
    >> in article [email protected], William
    >> Morse at [email protected] wrote on 5/1/04 7:32 PM:
    >>
    >>> Why should the fact that evolution is constrained by
    >>> physics imply that we should invoke physics as a
    >>> "primary explanation"?
    >
    >
    >> Good question. Physical constraints alone do not build an
    >> engine of work like life. They are not enough, which is
    >> why many folks, including myself, are now calling for a
    >> re-evaluation of the thermodynamic laws (either a
    >> modification of the second law, or the addition of a
    >> fourth law). We are striving to put the "dynamics" into
    >> the laws of thermodynamics. The traditional understanding
    >> of the second law as a "ONE WAY" traffic sign is only a
    >> constraint. It does not make anything go that way.
    >>
    >> Setting aside the potential for an improved understanding
    >> of physical dynamics, your question seems to imply that
    >> biology is somehow more than just its physical
    >> underpinnings. I am curious as to just what it is that
    >> you think it is about biology that is not physical. Is
    >> there biological metaphysics? If so, isn't the science of
    >> biology doomed due to the absence of rules that we can
    >> know of governing metaphysics?
    >
    > Dang! Now I have to try to remember what I was thinking
    > when I made that statment :)
    >
    > But before I do that: isn't the science of physics doomed
    > due to the absence of rules that we can know of governing
    > metaphysics?

    It would indeed lose its credibility if metaphysics exists
    IMHO; but them my position is that there is no such thing as
    metaphysics.

    > Assuming a reductionist stance for now - that biology
    > is explained by chemistry, and chemistry is explained
    > by physics

    I see this as a distortion of the reductionist viewpoint,
    albeit a common one. I see them as hierarchically related,
    rather than linearly stacked. You could, for example, drill
    down from physics (the most inclusive category) to biology
    (a subset of physics).

    > - then I have to ask the question: what explains physics?

    Physics theory.

    > Is there physical metaphysics?

    Not in my view.

    > There appear to be three possible answers - probably Dr.
    > John (Wilkins) can come up with more:
    >
    > (1) the cosmological argument is correct, and there is a
    > prime mover somewhere who decreed what the speed of
    > light would be, and what Planck's constant would be,
    > etc., etc.;

    I am not sure what you are saying here. AFAIK
    cosmological theory does not posit a role for a prime
    mover decreeing anything.

    > (2) there is an infinite chain of regression, and we will
    > always find a further reductionist reason for the
    > reason (protons are explained by quarks, quarks are
    > explained by string theory, string theory is explained
    > by something we haven't come up with yet, etc. ad
    > infinitum) I call this the turtle theory, after the
    > joke about the world being held up by sitting on the
    > back of a turtle - "but what holds up the turtle?" -
    > "another turtle" - "but what holds up that turtle?"-
    > "another turtle" - but what holds"- "give it up, kid,
    > it's turtles all the way down"

    I love this turtle picture myself, but I sure hope it is
    incorrect.

    > (3) the ontological argument is correct, and existence
    > implies essence. I actually like this argument, at
    > least compared to the alternatives, although I
    > disagree with St. Anselm that it proves the existence
    > of a Supreme Being. It seems possible to me that if
    > you have existence, then you must have non-existence,
    > so you have a 0 and a 1. Given a 0 and a 1 you can
    > construct binary mathematics, and from that you can
    > construct mathematics in general. Now I have no idea
    > how you get from that to Planck's constant, but that's
    > just a minor detail :)

    I like your thinking here. As we have been discussing in
    this thread, I see emergence as a path to quantum existence,
    so I am also optimistic about a theory that allows existence
    to imply essence without implying the parallel existence of
    a supreme being.

    > Having got that off my chest, my statement was really
    > based on my interpreting "primary explanation" as more
    > akin to final cause than formal cause.The mackerel has a
    > deeply forked tail because fluid dynamics dictates that as
    > the best shape for high speed swimming in water if
    > maneuverability is less important, but the reason that a
    > mackerel needs to swim fast with limited maneuverability
    > is related to selection for its niche.

    I agree. I also see all of this as part of physics, although
    not in reductionistic sense that you described above. I am
    talking about the physics of macroscopic phenomena.

    > I do believe that in some cases it is appropriate to
    > invoke physics or chemistry as a primary explanation. For
    > instance, I would argue that most animals are bilaterally
    > symmetrical because of chemical constraints on
    > development, not because of selective bias for that form.
    > I was mostly arguing against taking this to the extreme
    > position of using physics as the final cause for all of
    > biology. While this may be true, it is probably unprovable
    > and in any case is often of no help in our understanding.

    I suspect that you would come to a different conclusion if
    you recognized the relevance of physics to macroscopic
    phenomena through thermodynamics, which is exclusively about
    the behavior of macroscopic systems. In other words, it is
    intended to be about things like organisms and life in
    general. Why should we biologists ignore the aspect of
    physical theory that is about biology, not to mention all
    other macroscopic systems?

    Guy
     
  19. John Wilkins

    John Wilkins Guest

    William Morse <[email protected]> wrote:

    ...
    > But before I do that: isn't the science of physics doomed
    > due to the absence of rules that we can know of governing
    > metaphysics? Assuming a reductionist stance for now - that
    > biology is explained by chemistry, and chemistry is
    > explained by physics - then I have to ask the question:
    > what explains physics? Is there physical metaphysics?
    > There appear to be three possible answers - probably Dr.
    > John (Wilkins) can come up with more:

    I shan't, but you raise a very cute problem: if explanation
    is something along the lines of the n-d (nomological-
    deductive) model, where you have satisfactorily explained a
    phenomenon or explanadum E only so far as you have deduced E
    from a generalisation or law L and a set of boundary and
    initial conditions C [they teach us to talk like this, you
    know], how can metaphysics explain physics?

    For there are no laws or generalisations in metaphysics from
    which we can deduce or even infer the laws of physics or the
    very existence of a physical world.

    I shall have to think this one through, and publish a
    paper on it :)
    --
    Dr John S. Wilkins, www.wilkins.id.au "I never meet anyone
    who is not perplexed what to do with their children" --
    Charles Darwin to Syms Covington, February 22, 1857
     
  20. John Wilkins

    John Wilkins Guest

    Guy Hoelzer <[email protected]> wrote:

    > Dear Wirt,
    >
    > I am responding to a wonderful post of yours. You and I
    > are in extremely close agreement on these issues, in
    > general, but I want to "pick one nit" out of your post.
    > You and I have discovered our disagreement on this
    > particular issue before, but I thought it might be useful
    > to lay it out for discussion in sbe.
    >
    > in article [email protected], Wirt Atmar
    > at [email protected] wrote on 5/4/04 7:54 PM:
    >
    > > Whenever emergent properties are introduced into a
    > > philosophy of evolutionary design, a higher-order
    > > mysteriousness is simultaneously introduced into the
    > > process that treads dangerously close to vitalism.
    >
    > I often see the term "vitalism" used in this way (the way
    > I think you are using it), as a rhetorical punishment for
    > perceived false logic, or warning to avoid this direction
    > in our modeling of nature. I don't understand this
    > position. I see vitalism as something to be explained by
    > science, rather than avoided as if it must represent a
    > falsehood. I suspect that the term "vitalism" connotes
    > different things for us. To me it connotes an actively
    > driven system that behaves in ways that maximize its
    > functional effectiveness and persistence. Life certainly
    > does this, as well as any dissipative system (sensu
    > Prigogine).

    Vital fluids, interior molds, elan vital, entelechies and
    the like postulate an occult force as an explanation. When
    the mechanisms of reproduction, growth and metabolism were
    unknown, it might have been worthwhile to postulate them,
    but now it is merely mysticism. "Vitalism" is the theory
    that there is something qualitatively different *at every
    level* between life and nonlife - the vital force must
    explain why cells divide, why organisms grow, why they react
    to stimuli. But we know why they do these things, and there
    is no non-physical remainder left over to explain. I think
    you are anachronistically interpreting "vitalism" the term.

    Wirt is exactly right about emergentism. It is a claim that
    a property occurs at a physical level or scale which cannot
    be reduced to the properties of the components. Hence, for
    example, consciousness is the paradigmatic case of an
    emergent property, because it is supposed to have features
    that cannot be explained as the vector sum of all the
    dynamics of neurons and their environmental inputs. But each
    new discovery shows this to be false. Likewise with
    evolution. Each emergent property turns out to be either a
    cause for a research program to decompose it into its
    substrate, or can already be explained that way. People who
    rest satisfied with emergent properties do, indeed, tread
    close to mysticism and vitalism.
    >
    > I also take issue with your assertion that when "emergent
    > properties are introduced into a philosophy of
    > evolutionary design, a higher-order mysteriousness is
    > simultaneously introduced." Mysteries are almost always
    > parts of our models, especially in the study of such high-
    > order phenomena as evolutionary biology. That is what
    > assumptions are all about. Even our assumptions are
    > usually about very high-order phenomena, which themselves
    > would require hefty assumption sets to explain. I do not
    > see the introduction of emergent properties [note that
    > this is VERY different from the notion of emergent
    > systems] as introducing either mystery or vitalism into
    > theory. Pressure, for example, is an emergent property of
    > a collection of atoms, which is not definable for a single
    > atom in isolation. Would you say that introducing the
    > concept of pressure into physical theory invoked
    > additional mystery and "treads close to vitalism?"

    The primary claim made by emergentism is that you cannot
    account for the property in terms of its parts without
    remainder. Pressure can indeed be so accounted for - there
    is no emergence here. The classical example, introduced by
    Mill in his 1837 System of Logic, is the liquid properties
    of water, which he said could not be deduced from the
    properties of hydrogen and oxygen. But we do exactly that
    these days - you can model wuite accurately the dynamics and
    microproperties of water on a computer using only the known
    properties of hydrogen and oxygen atoms. It only took a
    computer that was more powerful than Mill had to hand.
    >
    > Cheers,
    >
    > Guy

    --
    Dr John S. Wilkins, www.wilkins.id.au "I never meet anyone
    who is not perplexed what to do with their children" --
    Charles Darwin to Syms Covington, February 22, 1857
     
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