Complexity

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

  1. r norman <[email protected]_comcast.net> wrote in
    news:[email protected]:

    > On Sat, 24 Apr 2004 04:46:39 +0000 (UTC), Tim Tyler
    > <[email protected]> wrote:

    >>Because of global competion for nutrients, organisms do
    >>not have to be in the same environment or physical
    >>location to be in competition with one another.
    >>
    >>I.e. those resources that are tied up in the form of
    >> forests should be subtracted from the pool of
    >> resorces available for forming bacteria.
    >>
    >>It is true that - at the moment - complex life is doing
    >>rather better on land than in the sea. However, that
    >>situation is probaly not going to last for very long. We
    >>can expect some serious reinvasions of the ocean as the
    >>land continues to fill up with complex organisms.

    > You persist in these strange ideas. Probably the most
    > critical nutrient (in the sense that it is usually a
    > limiting factor in growth) is nitrogen and the only source
    > for usable nitrogen by complex multicellular organisms is
    > nitrogen fixation by bacteria. All other limiting
    > nutrients like phosphorus or iron or whatever other trace
    > mineral are usable only when dissolved in water and then
    > the bacteria really do get first crack at them. Only in a
    > tropical rain forest do you find nutrients primarily tied
    > up in multicellular organisms and there they are almost
    > entirely in plants, certainly not animals. Again may I
    > remind you that this habitat, impressive as it is, forms
    > only a tiny fraction of the biotic world.

    Actually the total contribution of nitrogen to the nutrient
    cycle from anthropogenic sources (fertilizer production,
    fossil fuel combustion, and legume cultivation) is currently
    approximately equal to the amount of natural fixation.
    Unlike carbon dioxide, the potential impacts of this has
    received little attention in the popular press. The impact
    of anthropogenic phosphate production (also significant in
    comparison to natural phosphorus cycles) is probably better
    recognized by the public, although phosphate is generally
    the limiting nutrient only in fresh water environments. I
    would also note that, in those environments, rooted aquatic
    plants and floating macrophytes such as duckweed frequently
    outcompete cyanobacteria and unicellular algae for the
    available phosphorus.

    Now as to the thrust of Tim's argument that we will soon
    replace the nutrient cycling function of bacteria, I am
    somewhat dubious - but partly because I think it will prove
    cheaper to utilize existing natural cycles than to try to
    take over all these functions with technology. This argument
    reminds me of the dichotomy between Planet Managers and
    Planet Fetishers described by Evan Eisenberg in "The Ecology
    of Eden". Either technology will save us or the return to
    nature will triumph. Eisenberg thinks we need to find a
    middle way, and I tend to agree with him.

    Yours,

    Bill Morse
     


  2. R Norman

    R Norman Guest

    On Sun, 25 Apr 2004 19:59:18 +0000 (UTC), Tim Tyler <[email protected]>
    wrote:

    <snip all except the point about competition for resources>

    >r norman <[email protected]_comcast.net> wrote or quoted:
    >> On Sat, 24 Apr 2004 04:46:39 +0000 (UTC), Tim Tyler
    >> <[email protected]> wrote:

    >> >Because of global competion for nutrients, organisms do
    >> >not have to be in the same environment or physical
    >> >location to be in competition with one another.
    >> >
    >> >I.e. those resources that are tied up in the form of
    >> > forests should be subtracted from the pool of
    >> > resorces available for forming bacteria.
    >> >

    >> Only in a tropical rain forest do you find nutrients
    >> primarily tied up in multicellular organisms

    >there are *plenty* of other forests besides tropical
    >rain forests.
    >
    >The world's largest forests are in Russia. If you want to
    >see forests, it is not to tropical zones - but to Siberia -
    >that you should head.

    By "nutrients", ecologists refer to limiting items like
    nitrogen and phosphorus, perhaps iron and other trace
    minerals. These are the factors that limit productivity. We
    already had a go-around where I agreed that eukaryotes had
    the majority of carbon biomass, but that is not considered a
    nutrient for which there is competition. In terms of
    nitrogen and phosphorus, prokaryotes have by far more
    biomass than eukaryotes.

    Furthermore, in virtually all terrestrial habitats, soil
    stores a tremendous amount of the limiting nutrients. That
    is true of taiga, the spruce-fir coniferous forests in
    Siberia you are referring to. Only in tropical rain forests
    is the soil quite deficient in these factors -- most of the
    nutrients are tied up in the eukaryotic biomass.
    Furthermore, in every habitat on earth, it is the
    prokaryotes that generally control the availability of
    nutrients. So it there is to be simple competition for
    nutrients that controls things, the prokaryotes would win
    hands down in virtually every instance.

    I have never denied that there are large quantities of very
    large, very "complex" organisms in virtually all of the
    habitats I live in. Virtually all of my friends and even
    some of my relatives are large multicellular organisms. All
    I am trying to convince you of is the simple fact that we
    large, "complex", multicellular organisms are not "taking
    over" from the "simple" prokaryotes. They are here in
    enormous numbers. They have always been here, as long as
    life has existed on earth. And every indication is that
    they will continue to be here as a major and often
    controlling factor in the biosphere for as long as life
    persists on earth.
     
  3. Guy Hoelzer

    Guy Hoelzer Guest

    Hi Jim,

    Thank you for your well-informed comments. I think you are
    reading some excellent material related to complex systems
    theory. (Nicolis, Prigogine, Bar Yam).

    in article [email protected], Jim Menegay at
    [email protected] wrote on 4/26/04 8:12 AM:

    > IMO, while there may be some philosophical interest in
    > explaining complexity, complexity is not part of the
    > explanation for any phenomenon of interest to biology,
    > chemistry, or any other natural science. Some systems of
    > great structural complexity have simple behaviors, some
    > have complex behaviors, some have chaotic behaviors. But
    > the same can be said of systems that are quite simple
    > structurally. The notion of emergence is useful, but it is
    > an idea much older than the rest of "complexity theory"
    > and it is not really conceptually connected to any of
    > these newer ideas.

    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. Until we reach such a point, or the complex
    systems paradigm falls apart under its own weight, it will
    be important to have skeptics like you making reasoned
    arguments to the contrary. I, for one, remain optimistic
    that the few loose ends remaining in complexity theory will
    be satisfactorily tied up before long.

    Cheers,

    Guy
     
  4. Tim Tyler

    Tim Tyler Guest

    Jim Menegay <[email protected]> wrote or quoted:

    > IMO, while there may be some philosophical interest in
    > explaining complexity, complexity is not part of the
    > explanation for any phenomenon of interest to biology,
    > chemistry, or any other natural science. Some systems of
    > great structural complexity have simple behaviors, some
    > have complex behaviors, some have chaotic behaviors. But
    > the same can be said of systems that are quite simple
    > structurally.

    [...]

    "Self-organising systems" are the ones with the biological
    relevance.

    These are practically all complex systems. However not all
    complex systems exhibit self-organisation.

    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.

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

    Jim Menegay Guest

    Tim Tyler <[email protected]> wrote in message news:<[email protected]>...
    > Jim Menegay <[email protected]> wrote or quoted:
    >
    > > IMO, while there may be some philosophical interest in
    > > explaining complexity, complexity is not part of the
    > > explanation for any phenomenon of interest to biology,
    > > chemistry, or any other natural science. Some systems of
    > > great structural complexity have simple behaviors, some
    > > have complex behaviors, some have chaotic behaviors. But
    > > the same can be said of systems that are quite simple
    > > structurally.
    >
    > [...]
    >
    > "Self-organising systems" are the ones with the biological
    > relevance.
    >
    > These are practically all complex systems. However not all
    > complex systems exhibit self-organisation.
    >
    > 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.
    >
    > 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? Which definition did you
    have in mind when you say that practically all self-
    organizing systems are complex?
     
  6. Guy Hoelzer

    Guy Hoelzer Guest

    Tim,

    in article [email protected], Tim Tyler at
    [email protected] wrote on 4/27/04 2:32 PM:

    > "Self-organising systems" are the ones with the biological
    > relevance.
    >
    > These are practically all complex systems. However not all
    > complex systems exhibit self-organisation.

    Can you please provide an example of a system that you
    consider to be complex, but which does not tend toward self-
    organization? Perhaps you meant that the manifestation of
    self-organization is not realized by some complex systems
    due to external constraints. If so, I would describe these
    as networks that don't quite manifest complexity.

    > 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.

    > 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.

    OK.

    Guy
     
  7. Tim Tyler

    Tim Tyler Guest

    r norman <[email protected]_comcast.net> wrote or quoted:
    > Tim Tyler <[email protected]> wrote:
    > >r norman <[email protected]_comcast.net> wrote or quoted:
    > >> On Sat, 24 Apr 2004 04:46:39 +0000 (UTC), Tim Tyler
    > >> <[email protected]> wrote:

    > >> >Because of global competion for nutrients, organisms
    > >> >do not have to be in the same environment or physical
    > >> >location to be in competition with one another.
    > >> >
    > >> >I.e. those resources that are tied up in the form of
    > >> > forests should be subtracted from the pool of
    > >> > resorces available for forming bacteria.
    >
    > >> Only in a tropical rain forest do you find nutrients
    > >> primarily tied up in multicellular organisms
    >
    > >there are *plenty* of other forests besides tropical rain
    > >forests.
    > >
    > >The world's largest forests are in Russia. If you want to
    > >see forests, it is not to tropical zones - but to Siberia
    > >- that you should head.
    >
    > By "nutrients", ecologists refer to limiting items like
    > nitrogen and phosphorus, perhaps iron and other trace
    > minerals. These are the factors that limit
    > productivity. [...]

    "Nutrients" are sources of nutrition - of nourishment.

    Are you *sure* people are restricting the term to things
    that are in short supply? Is there any reference supporting
    such a usage?

    > We already had a go-around where I agreed that eukaryotes
    > had the majority of carbon biomass, but that is not
    > considered a nutrient for which there is competition.

    I do not see why that is relevant. Biomass is a simple
    enough concept. Only weighing certain nutrients seems like
    an attempt at confusing the issue.

    You seem to be arguing that - since prokaryotes fail to
    take full advantage of the available carbon, carbon
    should be ignored in biomass calculations. I don't see
    much sense in that.

    > I have never denied that there are large quantities of
    > very large, very "complex" organisms in virtually all of
    > the habitats I live in. Virtually all of my friends and
    > even some of my relatives are large multicellular
    > organisms. All I am trying to convince you of is the
    > simple fact that we large, "complex", multicellular
    > organisms are not "taking over" from the "simple"
    > prokaryotes. They are here in enormous numbers. They have
    > always been here, as long as life has existed on earth.
    > And every indication is that they will continue to be here
    > as a major and often controlling factor in the biosphere
    > for as long as life persists on earth.

    Small organisms may well persist on life's fringes - in
    environments large organisms can't easily enter.

    However I do think the /main/ trend among living organisms
    will be towards a single planetary-scale organism. Most of
    the roles played by bacteria today in terms of food
    production and chemical processing will be taken over by
    organisms which are sterile clones of organisms produced in
    factories. As such, although they may superficially remain
    microscopic chemical processing factories, their full
    reproductive phenotype will consit of a large number of
    clone organisms, the factory from which they came - and its
    R+D department.

    I.e. their fate will be the same as that of our other
    symbiotes: we will take over their reproductive
    processes - and eventually make them part of the
    phenotype of the dominant organisms.

    Such organisms will out-compete free-living ancestral forms
    for most applications - due to their being preferentially
    cultivated by the dominant living creatures.

    In the case of the bacteria, the ancestral free-living types
    will (literally) be driven underground.

    IMO, the most likely candidates for successful future small
    organisms are parasites and pathogens. These creatures may
    be with us for quite some time - though they probably won't
    come to outweigh us; and the larger and more complex the
    dominant organisms become, the more effort they are likely
    to invest in eliminating them.

    Ultimately, creatures will become larger because small
    creatures results in inefficiency and wastage in the form of
    internal friction in the form of conflicts between non-
    relatives. Bigger organisms will continue to out-compete
    smaller ones by exploiting cooperation and harmony to reduce
    internal friction and disharmony, and thus will utilise
    their resources more effectively.

    So far the limits on size have been imposed by phenomena
    such as asteroid impacts - and communication and
    authentication problems among spatially-distributed
    organisms. However these are problems which have solutions.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  8. R Norman

    R Norman Guest

    On Tue, 27 Apr 2004 21:32:33 +0000 (UTC), Tim Tyler <[email protected]>
    wrote:

    >r norman <[email protected]_comcast.net> wrote or quoted:
    >> Tim Tyler <[email protected]> wrote:
    >> >r norman <[email protected]_comcast.net> wrote or quoted:
    >> >> On Sat, 24 Apr 2004 04:46:39 +0000 (UTC), Tim Tyler
    >> >> <[email protected]> wrote:
    >
    >> >> >Because of global competion for nutrients, organisms
    >> >> >do not have to be in the same environment or physical
    >> >> >location to be in competition with one another.
    >> >> >
    >> >> >I.e. those resources that are tied up in the form of
    >> >> > forests should be subtracted from the pool of
    >> >> > resorces available for forming bacteria.
    >>
    >> >> Only in a tropical rain forest do you find nutrients
    >> >> primarily tied up in multicellular organisms
    >>
    >> >there are *plenty* of other forests besides tropical
    >> >rain forests.
    >> >
    >> >The world's largest forests are in Russia. If you want
    >> >to see forests, it is not to tropical zones - but to
    >> >Siberia - that you should head.
    >>
    >> By "nutrients", ecologists refer to limiting items like
    >> nitrogen and phosphorus, perhaps iron and other trace
    >> minerals. These are the factors that limit
    >> productivity. [...]
    >
    >"Nutrients" are sources of nutrition - of nourishment.
    >
    >Are you *sure* people are restricting the term to things
    >that are in short supply? Is there any reference supporting
    >such a usage?
    >
    >> We already had a go-around where I agreed that eukaryotes
    >> had the majority of carbon biomass, but that is not
    >> considered a nutrient for which there is competition.
    >
    >I do not see why that is relevant. Biomass is a simple
    >enough concept. Only weighing certain nutrients seems like
    >an attempt at confusing the issue.
    >
    >You seem to be arguing that - since prokaryotes fail to
    >take full advantage of the available carbon, carbon
    >should be ignored in biomass calculations. I don't see
    >much sense in that.
    >
    >> I have never denied that there are large quantities of
    >> very large, very "complex" organisms in virtually all of
    >> the habitats I live in. Virtually all of my friends and
    >> even some of my relatives are large multicellular
    >> organisms. All I am trying to convince you of is the
    >> simple fact that we large, "complex", multicellular
    >> organisms are not "taking over" from the "simple"
    >> prokaryotes. They are here in enormous numbers. They have
    >> always been here, as long as life has existed on earth.
    >> And every indication is that they will continue to be
    >> here as a major and often controlling factor in the
    >> biosphere for as long as life persists on earth.
    >
    >Small organisms may well persist on life's fringes - in
    >environments large organisms can't easily enter.
    >

    I don't know how worthwhile it is to keep rehashing the same
    old differences of opinion. You are the one who brought up
    the notion that large eukaryotes were outcompeting the
    prokaryotes by tying up available nutrients. You said (Apr.
    24) "Because of global competion for nutrients, organisms do
    not have to be in the same environment or physical location
    to be in competition with one another. I.e. those resources
    that are tied up in the form of forests should be subtracted
    from the pool of resorces available for forming bacteria."
    The fact is that carbon is not at all a limiting nutrient
    about which there is any real competition. All autotrophs
    are capable of fixing inorganic carbon which is abundant.
    The real issue of competition deals only with those
    resources which are limited. That is why I insist on
    focusing on nitrogen and phosphorus. And in terms of these
    two limiting nutrients, virtually all of the organic form is
    tied up by prokaryotes. The Whitman, Coleman and Wiebe paper
    previously cited in this thread says that 90% of the N and P
    is tied up in prokaryotes.

    You are entitled to your opinion about the future of life on
    earth. However I still claim you are really incorrect about
    the past and current status and role of prokaryotes in the
    total biosphere.
     
  9. Jim Menegay

    Jim Menegay Guest

    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.

    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. You seem to be using
    "emergence" to mean a process of change occuring in time.
    But I was using it to describe a relationship between the
    descriptive properties of a system and the descriptive
    properties of its subsystems. Time does not appear at all in
    my sense of the word "emergence", which is, I think, the
    standard one in this context.

    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! 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. The less obvious way is that the
    property itself is not new - the novelty is that this
    property becomes classifiable as emergent. 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. 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.
     
  10. Tim Tyler

    Tim Tyler Guest

    Guy Hoelzer <[email protected]> wrote or quoted:
    > Tim Tyler at [email protected] wrote on 4/27/04 2:32 PM:

    > > "Self-organising systems" are the ones with the
    > > biological relevance.
    > >
    > > These are practically all complex systems. However not
    > > all complex systems exhibit self-organisation.
    >
    > Can you please provide an example of a system that you
    > consider to be complex, but which does not tend toward self-
    > organization?

    TV-screen static has very large Kolmogorov complexity - but
    shows not the slighest hint of self-organising processes.

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

    Tim Tyler Guest

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

    > > "Self-organising systems" are the ones with the
    > > biological relevance.
    > >
    > > These are practically all complex systems. However not
    > > all complex systems exhibit self-organisation.
    > >
    > > 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.
    > >
    > > 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? Which definition did you
    > have in mind when you say that practically all self-
    > organizing systems are complex?

    Now you're trying to get me to give a binary definition of
    complexity ;-)

    In this case, I'm happy to go with the plain
    dictionary entry:

    "complex": consisting of interconnected or interwoven parts.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  12. Guy Hoelzer

    Guy Hoelzer Guest

    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 there meanings as vague.

    > 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. 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.

    > 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.

    > 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.

    > 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!

    You have misunderstood Bar-Yam's use of the term. He uses
    the phrase "emergence of complexity" in the same way I do.

    > 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.

    Yes; the property might never have existed for any other
    system before, but it is much more likely to be a newly
    manifested example of the property. Every tornado emerges
    as a newly manifested vortex, but vortices have been
    manifested before.

    > 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? You might want to take a look
    at the recent book by Harold Morowitz (a physicist) called
    "The emergence of everything". This book should make much
    more concrete for you the meaning of emergence.

    > 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.

    As does "sloppy" listening.

    > 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?

    Guy
     
  13. Tim Tyler

    Tim Tyler Guest

    r norman <[email protected]_comcast.net> wrote or quoted:
    > On Tue, 27 Apr 2004 21:32:33 +0000 (UTC), Tim Tyler
    > <[email protected]> wrote:
    > >r norman <[email protected]_comcast.net> wrote or quoted:

    > >> I have never denied that there are large quantities of
    > >> very large, very "complex" organisms in virtually all
    > >> of the habitats I live in. Virtually all of my friends
    > >> and even some of my relatives are large multicellular
    > >> organisms. All I am trying to convince you of is the
    > >> simple fact that we large, "complex", multicellular
    > >> organisms are not "taking over" from the "simple"
    > >> prokaryotes. They are here in enormous numbers. They
    > >> have always been here, as long as life has existed on
    > >> earth. And every indication is that they will continue
    > >> to be here as a major and often controlling factor in
    > >> the biosphere for as long as life persists on earth.
    > >
    > >Small organisms may well persist on life's fringes - in
    > >environments large organisms can't easily enter.
    >
    > I don't know how worthwhile it is to keep rehashing the
    > same old differences of opinion. You are the one who
    > brought up the notion that large eukaryotes were
    > outcompeting the prokaryotes by tying up available
    > nutrients. You said (Apr. 24) "Because of global competion
    > for nutrients, organisms do not have to be in the same
    > environment or physical location to be in competition with
    > one another. I.e. those resources that are tied up in the
    > form of forests should be subtracted from the pool of
    > resorces available for forming bacteria."

    A point I stand by - you don't have to occupy the same niche
    to be able to compete with something - using the same
    nutrients is enough.

    I did say that bacteria were "in the middle of a period of
    decline" and that "their decline seems likely to continue".

    As the roles for complex organisms continue to grow, they
    will continue to compete for resources with simpler
    creatures.

    Such processes can be seen to be at work at the moment, and
    have been going on for billions of years.

    I don't think is is reasonably possible to dispute that the
    complex organisms are getting a larger share of the resource
    pie as time passes - since it's plain enough that they
    started off with no resources at all.

    I suppose it could be argued that they haven't made /that/
    much progress since trees were invented - but I don't buy
    this - I think the rise of complex organisms has a
    continuous character - and that there's still significant
    potential for future development.

    Absolute numbers of bacteria may actually increase - but
    their proportion of life's total has fallen historically.

    I think it will continue to fall for some time to come - as
    they are systematically outwitted by the complex organisms
    which they must either compete with or crawl away from.

    Existing symbiotic relationships with bacteria are likely to
    be terminated - now that we can simply steal most of the
    chemical secrets of the bacteria and make them our own.

    As an example of the sorts of things that will happen, we
    will come of evict our gut bacteria. Our insides will be
    sterilised and we will absorb predigested food -
    dispensing with farts and innumerable intestinal pathogens
    in the process.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  14. Guy Hoelzer

    Guy Hoelzer Guest

    in article [email protected], Tim Tyler at [email protected]
    wrote on 4/29/04 4:25 PM:

    > Guy Hoelzer <[email protected]> wrote or quoted:
    >> Tim Tyler at [email protected] wrote on 4/27/04 2:32 PM:
    >
    >>> "Self-organising systems" are the ones with the
    >>> biological relevance.
    >>>
    >>> These are practically all complex systems. However not
    >>> all complex systems exhibit self-organisation.
    >>
    >> Can you please provide an example of a system that you
    >> consider to be complex, but which does not tend toward
    >> self-organization?
    >
    > TV-screen static has very large Kolmogorov complexity -
    > but shows not the slighest hint of self-organising
    > processes.

    OK. While I find Kolmogorov complexity (KC) to be a valuable
    measure, it's isolated value does not inform us of whether
    or not you have a complex system in the emergent, physical
    sense. Despite my ignorance of TV-screen static, I have two
    hypotheses that could account for your observation that
    would be consistent with my understanding of complex
    systems. First, it might be merely complicated, which could
    still result in a large KC value. Second, self-organization
    of systems manifested in space generically exhibit a
    threshold spatial scale at which self-organization
    manifests. This is why I used the phrase "tend toward self-
    organization", as opposed to "self-organize." If the scale
    of the system is too small, it will tend toward self-
    organization without actually self-organizing. I know that
    this logic can appear slippery, but it is not. A similar
    phenomenon would be the movement of a fleck of dust floating
    in the air. The dust particle is within the reach of the
    earth's gravity, yet it does not fall. Suspended particles
    are always tending to fall (the "feel" the pull of gravity),
    but they don't actually fall unless their mass and density
    surpass a threshold, just like you and I feel the pull of
    gravity without falling through the floor.

    >>> 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.

    Regards,

    Guy
     
  15. Peter F.

    Peter F. Guest

    "Tim Tyler" <[email protected]> wrote in message
    news:[email protected]...

    > 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.
    > 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.

    Apropos which, an Evolutionary Philosophical Thought: One
    might shoose a fairly encompassing way of looking at it
    through a zooming lense; such as that self-organization is
    What Is in_ self-knotting _ and complexity increasing
    formation; and that this can be seen to occur at different
    levels; AS DO our efforts to explain this multifaceted
    phenomenon.

    (BTW, the simulatnaeously highest an lowest, simplest, and
    most general, of all evolution-relevant explanations, would
    have to be: "What Is self-patterns").

    P
     
  16. Jim Menegay

    Jim Menegay Guest

    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?

    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.
     
  17. Irr

    Irr Guest

    "Tim Tyler" <[email protected]> wrote in message
    news:[email protected]...
    > Guy Hoelzer <[email protected]> wrote or quoted:
    > > Tim Tyler at [email protected] wrote on 4/27/04 2:32 PM:
    >
    > > > "Self-organising systems" are the ones with the
    > > > biological relevance.
    > > >
    > > > These are practically all complex systems. However not
    > > > all complex systems exhibit self-organisation.
    > >
    > > Can you please provide an example of a system that you
    > > consider to be complex, but which does not tend toward
    > > self-organization?
    >
    > TV-screen static has very large Kolmogorov complexity -
    > but shows not the slighest hint of self-organising
    > processes.
    [snip]

    Certainly this TV static example is true, and another
    outstanding example of why Kolmogorov complexity isn't
    suited to biology. Kolmogorov complexity (KC) is really a
    measure of regularity, which isn't particularly interesting
    in discussing biological complexity.

    KC is also particularly ill-suited to your dictionary
    definition of complex as "consisting of interconnected...
    parts" in another part of this thread. You can certainly
    have networks that are simple -- being highly regular -- or
    networks that are complex -- connections are highly random
    (low to high Kolmogorov complexity, respectively). You can
    also have networks within an "intermediate" regime, akin to
    Watts' & Strogatz's small world network, that are not only
    complex in an algorithmic sense but are also highly
    analogous to real world systems, many of which display both
    self-assembling and emergent properties.

    So to beat my dead horse, many of the nitpicks in this
    thread seem to come down to a frustratingly plastic
    definition of complexity and how to measure
    it.
     
  18. 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 4/28/04 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/ComplexityMea-
    sures.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.

    > > 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/

    > > 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.

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

    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.

    The first is from a review of a debate between Maynard Smith
    and Kauffman: http://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!"

    The second quotes Robert May about SFI: http://www.santaf-
    e.edu/sfi/publications/Bulletins/bulletinSummer01/feature-
    s/may.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."
     
  19. Tim Tyler

    Tim Tyler Guest

    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

    > > 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 :-(

    Cosma Shalizi offers some criticism of the whole idea - and
    winds up offering a purely memetic 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.
    --
    __________
    |im |yler http://timtyler.org/ [email protected] Remove
    lock to reply.
     
  20. Tim Tyler

    Tim Tyler Guest

    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.

    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.

    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.

    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).

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