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Author
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Topic: ID Predictions made by an Engineer
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Art
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Member # 179
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posted 28. December 2002 14:33
Hi Irving,
You said:
quote:
Thanks for your response Art. I'm interested in what you mean by "temporal terms."
Using the example of paving stones - given one kind of stone, it is easy to accept that a large array of single units will take on a particular shape. Moreover, it’s easy to see how changes (even very subtle ones) in the shape of the individual stone can be manifest as dramatic changes in the shape of the patio.
Now, suppose that we are using two kinds of stone. The ultimate shape of the patio will reflect the shapes of each of the two stones, and their relative placements. The latter aspect involves a temporal element - we can add, first, one stone, then a second. Or we can add ten of stone “1”, then a mixture, then ten of the second. Etc., etc. The length of time of each stage (stone “1”, stone “2”, the mixture) as well as the “composition” of each stage can affect the final outcome.
The final outcome, then is influenced by the physical nature of the stones, and of the sequence in which they are placed.
quote:
One such "sub-attribute" I would consider would be uniformity. To take a simple example of scalability, think of a square paving stone. Now some would consider a perfectly square paving stone as something Intelligently Designed from the start, but it could be argued that given enough time, the seemingly improbabable may have occured to produce such a paving stone. But anyway, given the paving stone itself, if one were to wander onto a beach and see an 8 x 8 grid of paving stones, all oriented the same way, and all equa-distant from each other, one would immediately conclude intelligent design. (Obviously another way of looking at the old watchmaker analogy).
What leads to this conclusion, is not the over-all complexity, but the uniformity of the design. I suggest that it would be striking to come upon a beach in which all the grains of sand were perfectly aligned with each other in a perfect grid. The design of the "patio" was scaled-up from the scalable design of the paving stone. It may be, that what makes the paving stone scalable, is the uniformity of the paving stone's design--its edges and corners.
Using this approach, one might ascribe to very simple crystals a design origin.
I guess this leads to the age-old question - since such apparent order seems to be “ingrained” in the fundamental laws of phyics, do we conclude that these laws are themselves “authored”?
quote:
While this concept is a different view of Specified Complexity than Dembski's METHINKS... analogy, in scalable design, it is uniformity that makes up the specified portion of specified complexity.
I am not sure I would agree. Maybe you could elaborate.
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Irving
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posted 29. December 2002 17:51
Thanks again Art. It seems your post may be clarifying things for me.
quote:
Using the example of paving stones - given one kind of stone, it is easy to accept that a large array of single units will take on a particular shape. Moreover, it’s easy to see how changes (even very subtle ones) in the shape of the individual stone can be manifest as dramatic changes in the shape of the patio.
Just a small point of clarification here...by shape do you mean design? While the size of the pavers would dictate how close the patio could conform to an irregular edge, changes in shape of the individual pavers could dramatically impact the design of the patio (even though it may fill the same area). I think we are using shape and design interchangibly here...correct?
quote:
The final outcome, then is influenced by the physical nature of the stones, and of the sequence in which they are placed.
Yes, an aspect that makes designing for scalability fundamentally different than "ad hoc" design. Scalability design requires a vision of the endstate, or at least a series of possible extended states from the start. Random Mutation & Natural Selection is an "ad hoc" design process with selection pressures dependent on the immediate rather than the longterm outlook.
quote:
Using this approach, one might ascribe to very simple crystals a design origin.
I guess this leads to the age-old question - since such apparent order seems to be “ingrained” in the fundamental laws of phyics, do we conclude that these laws are themselves “authored”?
You are correct in both assumptions. It could be said that orbital mechanics is uniform since all planets orbit in ellipses, or that since everything I drop falls to the ground, that is uniformity. However, since these are the results of fundamental laws, it doesn't get us very far in differentiating design from nature...(if that is to be the desire). Whether the universe's fundamental laws are some sort of IEEE Engineering Standards, can be for another debate.
But if we are attempting to detect design from within the universe and its fundamental laws, it appears we will need to make a distinction. Would you accept that Uniformity is the antithesis of Randomness? That the quality of random number generators are evaluated by the lack of uniformity in their results?
If so, then I would propose to look for uniform attributes in environments in which neither uniformity nor randomness (for those attributes) is excluded by fundamental laws. Expressed another way: Uniformity in an environment susceptible to randomness is an indicator of design.
quote:
quote[Irving]:
While this concept is a different view of Specified Complexity than Dembski's METHINKS... analogy, in scalable design, it is uniformity that makes up the specified portion of specified complexity.
I am not sure I would agree. Maybe you could elaborate.
I'll attempt to elaborate...
If we agree on the following definition of Specified Complexity.
Specified complexity is displayed by any object or event that has an extremely low probability of occurring by chance, and matches a discernable pattern.
The scrabble piece analogy, often used for specified complexity, uses the English (or some other) language as the "discernable pattern." The advantage is that it is a pattern we already recognize. However, I might be hard-pressed to distinguish a sentence composed of Chineese characters from something a bird with ink-stained feet walked across. How does one discern a pattern in which there has been no education in the discernment? The current approach is to define life as the discernable pattern, since the random collection of chemicals in a beaker doesn't result in life.
The driver for this approach is the same as the one that afflicts the SETI program. How does one discern an intelligence pattern, when you don't have any knowledge of the intelligence behind the pattern you are looing for?
This brings us back to the point that Uniformity is the antithesis of Randomness. Random Mutation & Natural Selection is an "ad hoc" design process that would not exhibit uniformity in its design. Objects with Specified Complexity can fall into four quadrants (Highly Specified, High Complexity; Lowly Specified, High Complexity; Highly specified, Low Complexity; Lowly Specified, Low Complexity). The patio is Highly Specified, Low Complexity. The specification of the patio, is it's uniformity. Micro-processors are Highly Specified, High Complexity. Uniformity can exist in highly complex objects.
To bring me back to a previous example, canals on Mars would be Highly Specified, Low Complexity. Intelligent Design is inferred, since (unlike mineral crystals) water flows aren't constrained by fundamental laws to flow in straight lines. If straight lines are found, the water flow is considered to be specified.
[ 29. December 2002, 18:51: Message edited by: Irving ]
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kyle7
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posted 03. January 2003 06:26
Charlie D.,
Biologists have also raised the same concerns that I am addressing (e.g. Denton, Behe, and others). The large phase space does present Neo-Darwinian evolution with a problem.
You seem to miss my point about ID. Biologists typically use experimental data in their analysis of evolution. They observe that life forms are able to adapt to their environment (at least to some degree). They then extrapolate that transpecific evolution (macro-evolution) has occurred. My theory is that the robustness of life forms accounts for the adaptations observed by biologists. Rather than supporting naturalism, the observed evolution supports ID. I contend there is a range to the robustness and beyond that range change is impossible. Specifically, the development of new biological systems is outside the realm of the possible given the large phase space associated with the possible mutations. Biologists that support ID should be able to develop experiments to verify this theory.
To clarify the notion of a range associated with biological evolution, it is instructive to examine engineering design. Engineers design new mechanisms that have to operate within a specified environment. Typically, the design requirements specify the environment or environments of operation. For example, we may design an airplane to operate only in clear weather. This constraint would lead to a very different design compared to an airplane that had to operate in a multitude of different environments (e.g. desert, tropical, bad weather, near-ocean, arctic, etc.). The more the environments the more difficult the design. An airplane that has to operate in cold arctic weather needs to have deicing mechanisms. For example, hot bypass air from the engine may be directed over the inlet of the engine or the leading edge of the wings to prevent ice buildup. Typically, engineers establish specific ranges of operation. For example, the clear weather airplane my be able to operate within the range of temperature of say 33 F to 120 F. Operating within the allowed range of temperature will ensure the life of the airplane, while operating outside the range can result in catastrophic failure. The plane designed to operate in cold weather would have a range of say –100 F to 120 F. The deicing mechanisms would allow for the greater range of operation.
Biological systems are similar to man-made mechanisms. They are designed to operate in a verity of environments. The more the environments the greater the complexity. A unique characteristic of biological systems is that over the eons of time the environments change sometimes significantly. The design of biological systems must include the extraneous systems or modified designs to enable the existence of the life forms over a broad range of environments. Rather than include all the extraneous systems throughout all time, the designer opted to have the extraneous systems switched on or the design modified for optimal performance. The genome however carries the information throughout the generations. This ingenious design enables the mechanism to be highly robust and efficient for each generation. The range of adaptation of biological systems is constrained by what was programmed into the genome. The phase space is constrained by the mechanism enabling the evolutionary changes to occur. The phase space without imposed constraints does not allow change given the magnitude of the phase space associated with the genome. The biological systems may be compared to momentum based propulsion systems (e.g. solar sails). As momentum based propulsion systems don't have to carry fuel, so the biological systems don't have to carry added systems or complex adapting systems. Both the momentum-based propulsion systems and the biological systems are therefore more efficient.
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kyle7
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posted 03. January 2003 06:51
Art,
You say the following:
quote:
When I read your engineering approach, the first thing that strikes me is that your ideas lead inexorably to the proposal that living things must possess tens or hundreds of fold more genes than they actually do (for example, this is what your suggestion that "Genetically, all the locations on the skin where the feathers would form would have to be specified" conveys to me). I think that you may need to alter your view of genes and how they work, taking into account, as a hypothetical example, that a very small number of genes can more than suffice for, as an example, specifying the thousands or millions of locations of feathers on an organism.
Biologists don't know all the genes that are related to the feather. How can you say that my view (or what you perceive to be my view) would require tens or hundreds of fold more genes?
Also, if biologists don't know fully how the genes work, how can you say that my view of how genes work is incorrect?
Using an engineering perspective does give insight into the interrelationships of genes and how genes may work. Also we can gain insight by examining engineering and manufacturing processes. An engineer develops the plans to construct some artifact. If you have ever looked at engineering drawings, you will notice that all the detailed information is provided so the builder can construct and build the artifact. The genome is like the engineering drawings, because it contains the information for building the life form. Not only does it contain the plans for the life form, but it builds the machines that construct the life form – the proteins. All the information must be present or problems will be encountered in the construction process. The main point of my previous posts is that the phase space is large and the interconnection of the genome is complicated thus making it very difficult for the Darwinian mechanism to build new structure or systems. Any significant change requiring many mutations is also near impossible. The examination of life from an engineering systems perspective brings out this problem. Even "simple" devices like feathers are very complicated. We can analyze feathers in a number of ways. For example, we can examine the type of feathers and their structure. There are a number of different types of feathers: semiplume, down, filoplume, vaned, etc. All of these have specific characteristics. Vaned feathers have a umbilicis (tip of quill), the calamus (quill), the rachis (quill near the vanes), and the vanes. Looking closer at the feather with a microscope, there are the barbicels that lock adjacent barbs together by their hooklike structure. The feather is highly symmetrical. The genome must specify the shape of the feather, all the features and the color patterns. NeoDarwinists must perform a lot of hand waving to explain the origin of feathers found on birds. Feathers are made of karatin and are chemically dissimilar to hair, nails, and scales – the other forms of karatin. My main point, however, is that the mutational phase space required to develop feathers would be so large that the time frame of 4.5 billion years would not allow them to develop. Ironically, the fossil record (though really there is no fossil record of feathers) seems to suggest that feathers appeared rapidly within a short time period. Even if we restricted the feather to one gene the phase space associated with the gene is large as my previous post shows (4^1000 = 1.147859 E602 or 3^1000 = 1.3221 E477 if we are more conservative). So, it is true there is enough information within an average gene to possibly specify the location of feathers. A systems engineering perspective, however, brings the notion of one gene into question. Again, the number of mutations required to develop feathers would be astronomical given the large phase space even if there was one feather gene.
We can also examine the boundary conditions (including the time domain) associated with the feathers to understand the number of genes that play a role in the development of feathers. Obviously, a feather must connect to something. That something must also have a gene or genes that specifies it. Feathers start off as a small lump in the epidermis, so the genes that specify the epidermis have a relation to the feathers. Most probably, the genes of the epidermis describe the location and type of feathers. Epidermal and dermal cells actually develop the feathers. Genes must also specify this cell type. The thyroid and pituitary glands send chemical signals to the cells that spur on the feathers growth. Genes must describe the thyroid and pituitary glands. Also, the brain controls the thyroid and pituitary glands so there must be additional genes that describe the brain that control the formation of feathers. Birds also molt, during which time the birds lose the old worn feathers and grow new feathers in their place. Genes must play a role in this process. Primary flight feathers are connected directly to the bone of the outer wing. Genes of the wing bones therefore relate to the feathers. Obviously, there are many genes that play a role in the development of feathers if one examines the feathers more from a systems-engineering perspective. We could perform other engineering analysis such as examining the functional relationships of feathers to other systems. This would identify additional genes that relate to the feather.
Art, you also say,
quote:
Also, it pays to keep in mind facts such as that, in the present-day human population, each and every gene - indeed, each and every base pair in the genome - is sampled by mutational change in a generation. This, and the preceding consideration, have vast effects on the sorts of calculations you are attempting.
You seem to miss my point. The phase space is so large that even with large populations the mutational phase space cannot properly sample the genome to explain the evolutionary changes. My ID theory is that the ability to adapt genetically is designed into the genome -- like brakes that adapt to the road conditions. The empirical evidence (as well as the evidence from the fossil record) that evolutionists tout as evidence of NeoDarwinian evolution is actually evidence for design – if the details are examined.
I should also point out that Dembski also seems to allude to this theory in his book, No Free Lunch (pg 313). He describes some key problems that a Design Research Program may address. The relevant problems that seem to relate to my theory are the following:
- Constraint Problem – What are the constraints within which the designed object functions optimally?
- Variability Problem – What degree of perturbation allows continued functioning? Alternatively, what is the range of variability within which the designed object functions and outside of which it breaks down?
- Separation of Causes Problem: How does one tease apart the effects of intelligent causes from natural causes, both of which could have affected the object in question? For instance, a rusted old Cadillac exhibits the effects of both design and weathering.
Although, I call the theory "my" theory, I should point out that it is not original given that others have voiced similar theories.
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charlie d.
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posted 03. January 2003 10:50
Is it just me, or sometimes these discussions feel like some kind of intellectual "whack-a-mole" game? You think you've knocked an argument right on the head, and hop it comes out again a few threads later...
![[Wink]](wink.gif)
Mod: I know, I know. I just couldn't resist. I know it feels the same to you, go ahead and whack this post. ![[Big Grin]](biggrin.gif)
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Irving
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posted 03. January 2003 17:09
Allow me to ask kyle7's forgiveness if it appears I'm taking over his thread. I'm indeed interested in methodology to calculate mutation probabilities over time, and I wish that topic to continue. However, perhaps my own interest in exploring scalability as an indicator of design may relate in someway. A phase space issue as kyle7 puts it.
In any event, I'd like to take the paving stone and the scalable patio concepts a little further so see what develops. I would also like to see agreements or disagreements with the concept previously speculated that Uniformity in an environment susceptible to randomness is an indicator of design.
To expand the complexity of the paving stone example, consider the attached diagram.
Many websites use small scalable images to create their backgrounds. This graphic is a piece of one such example. To keep things simple, I selected an
image that is scalable in a single, verticle dimension. This image can be left as is, or combined with an infinite replication of itself to create a seamless verticle image. It is my conjecture that the scalable properties of this image indicate beyond reasonable disagreement--intelligent design. I would further
consider (though may be persuaded otherwise) that this image is impossible to arrive at via random mutation and natural selection (RM & NS). While a random image generator theoretically could produce the image "in total," I maintain that this image cannot be produced via RM & NS since key attributes of this image are immune from certain selection pressures and that it is these attributes that give the image specified complexity. This image may be
produced via random mutation and intelligent selection.
I hope this image illustrates the point that as the individual component in a scalable architecture becomes more complex, the engineering design challenge required to maintain function as the components scale is of a complexity orders of magnitude greater.
Recognize that every pixel in the bottom row of pixels must perfectly match in color and intensity it's corresponding pixel in top row. Yet, this just scrathes the surface since every pixel in the image must not only support the "solid-state" purpose of the image proper, but also be precisely aligned so that when scaled, the continuity of the image is maintained. This can only be arrived at if there is "foreknowledge" of the need for this continuity.
While I can agree that a selection environement weighted for an image that coveys a solid-state concept could allow for the RM & NS of a similar image, the "future-requirement" that the design must also be scalable drives the intelligent design indication of this particualar image. In a scalable design, the individual component must "operate" (or live) by itself, as a pair, or when
replicated by the thousands. Rm & NS can make a good case that it can arrive at an "operable" (living) component, but it cannot arrive at a scalable component of proper complexity since the scalable requirement is outside the selection environment during the evolution of the individual component. I would also make the case that a multitude of individually evolved components
(solid state images) would better match the individual selection environment better than this scalable image. Therefore it is quite likely that RM & NS would reject a potentially scalable component in favor of a better individually-matched non-scalable component.
[ 03. January 2003, 17:10: Message edited by: Irving ]
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Neil A. Wells
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posted 12. January 2003 17:31
I apologize for heading off the original thread, but I must comment on Irving's hypothetical example of an occurrence of well-fitted paving stones as being clear evidence for design:
"One such "sub-attribute" I would consider would be uniformity. To take a simple example of scalability, think of a square paving stone. Now some would consider a perfectly square paving stone as something Intelligently Designed from the start, but it could be argued that given enough time, the seemingly improbabable may have occured to produce such a paving stone. But anyway, given the paving stone itself, if one were to wander onto a beach and see an 8 x 8 grid of paving stones, all oriented the same way, and all equa-distant from each other, one would immediately conclude intelligent design. (Obviously another way of looking at the old watchmaker analogy)."
There is a wonderful and instructive parallel to this mentioned in the writings of Erik Von Daniken (Chariots of Fire, etc.) and William Corliss, 1978, "Ancient Man: A Handbook of Puzzling Artifacts", p.241 ff., and others involved in natural and archeological 'oddities'. These are 'pavement-like stones' with right-angle corners, that seem to have been cut and fitted, in single or double lines roughly parallel to the present shoreline, but under 2 -5 m of water. In any one area, the blocks tend to be fairly uniform in size and thickness (at least at first glance), although these can vary along the feature. Also, regularity can be exaggerated if one imagines that some of the [original] blocks have become broken by shifting under their own weight since they were laid down. Several writers have stated conclusions to the effect that 'human agency must have been involved', following reasoning very like the logic proposed by Irving, and by ID in general. Some writers have taken these 'underwater roads' as evidence for Atlantis or visitors from space (some of the blocks are very big).
I consider those interpretations crazy, but the features exist, and the descriptions of the features are accurate. Corliss reports that some of these are coquinas (shell hash), and that they appear to have been cemented by fresh groundwater during low sea levels during the Pleistocene. They developed orthogonal (right-angle) jointing, and became slightly separated by wave attack when sea level rose after glaciation.
I would add the following. Tropical carbonate (white sand) beaches typically develop beach rock, where spray and swash infiltrate into hot, dry-ish beach sands and evaporate, causing extensive and very rapid precipitation of calcium carbonate, creating a thin to quite thick layer of lithified limestone just below the surface of the beach. This stuff is famous among geologists because you can find year-old "fossil" beer cans and Coca-Cola bottles encased in solid rock. This rock is white and smooth when fresh, but when it becomes exposed (whenever the line of the beach shifts a little bit) it quickly becomes so blackened and corroded by phytokarst that tourists have been known to mistake it for basaltic lava). If sea level rises or falls, or the shoreline shifts (which shorelines are forever doing), waves can easily undercut the beachrock (as it is strictly a near-surface feature, and the sands underneath remain unlithified). As the beach rock is undercut, it breaks, often in remarkably rectilinear blocks, usually with one set of joints parallelling the undercutting shoreline and the other at right angles to it. (I'm not sure I completely understand why these sorts of joints are orthogonal rather than conjugate shear fractures (vertical and at right angles, rather than X-shaped fractures), but orthogonal fracture is a common natural style of jointing (see any structural geology textbook.) As these blocks slump down a little, they may break further and can rotate a bit or become slightly tilted, but they tend not to move very far, if at all, due to their size and weight, and they can end up looking like rather well fitted masonry. More than a few Bahamian shorelines are today lined by blocks of fractured beachrock that formed at slightly higher sea levels or higher on a beach, that has been dropped down closer to the modern wave level. There are also lithified fossil beach deposits with fossil broken beach-rock blocks from even higher sea levels, as in one of the caves on San Salvador Island.
What I find instructive about this example is that we have here a clear example of something that gives every appearance of being artificial and designed, yet it results from some remarkably simple and indeed downright inevitable natural processes, and the whole mystery disappears when one develops a little expertise on the subject. Neither improbability nor design are involved.
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Irving
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posted 12. January 2003 19:20
Neil,
quote:
I apologize for heading off the original thread, but I must comment on Irving's hypothetical example of an occurrence of well-fitted paving stones as being clear evidence for design:
Oh your not too far off...and anyway I appreciate the time you took to respond. I would like to take the opportunity to respond and maybe clarify. I don't believe I ever used the words, "clear evidence." I have suggested that Uniformity in an environment susceptible to randomness is an "indicator" of design. I never proposed that it was definitive by itself.
Art also made an illustration using mineral crystal structures as uniformity in Nature, and may I also offer up Quasars as another example. However, I consider uniformity in the context of scalability (sub-attribute I called it) rather than hinging the design inferrence upon uniformity by itself (note inferrence not proof). In either case, your post also illustrated that others noticed the striking features and possibly attributed them to intelligent design (The Bimini road I believe you are referring to). I believe this reinforces the point that, in most cases, uniformity is one of the first physical attributes analytically used to triage features between possibly design, and possibly natural.
quote:
What I find instructive about this example is that we have here a clear example of something that gives every appearance of being artificial and designed, yet it results from some remarkably simple and indeed downright inevitable natural processes, and the whole mystery disappears when one develops a little expertise on the subject. Neither improbability nor design are involved.
I note the use of the word "inevitable," much like the fundamental laws Art and I discussed earlier. The issue then is how much does randomness play in the environment, and is uniformity present in the random environment. In your example, at first blush, there appeared to be uniformity in a random environment (hence design inferrence). Yet, further investigation revealed the environment to not be entirely random, and may I also suggest that the features to not be entirely uniform?
While this is a good discussion for clarification of concepts, like yourself, I hope it doesn't detract too far from the main issue of scalability. I have used the paving stone example for simplicity of a scalable design, though I myself indicated that paving stone development could be argued to be possible from Natural causes. It is purely a simplified example of scalability. What I'm really looking at is the inherient difficulty in designing scalable components as the complexity of the individual component increases. The image I posted earlier offers a more complex example (if the server I posted the image on ever comes back on line!).
Wave action, erosion, and a host of other natural actions can create an appearance of uniformity by acting on consecutive components simultaneously. Draw a squggly line in the sand, and it may then appear that the grains on one side of the line have been perfectly placed to mirror the grains on the other side. The amazing alignment is a product of its simultaneous manufacture. However, consider the same issue when only one side has evolved independently. Only after the component has evolved to fit it's environment, is a duplicate of the component placed in conjunction with it. It is in this instance that the probability that the items would perfectly align is by mere random chance since the criteria of conjunctive alignment was outside the selection space during the original evolution. It is the incredible chance probability of this alignment that demonstrates a specified complexity in the aligning features and functions.
[ 12. January 2003, 19:26: Message edited by: Irving ]
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Irving
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posted 21. January 2003 17:54
Allow me to continue the discussion on scaled architectures by advancing the scaled component example into a scaled architecture. A primary attribute of a scaled architecture (due to its replication of components) is uniformity. As discussed earlier I consider it improbable that uniformity can be created via a random process in a random environment. The other aspect of scaled design, is the conceptual requirement that replicated components must work together. This places a scaled architecture outside the notional ability of natural selection since the scaling requirement is outside the selection space during the development of the original component. Therefore I suggest that it is improbable that scaled architectures can be created via random mutation and natural selection (RM & NS); hence scaled architectures are an example of Specified Complexity.
This concept, no doubt, adjoins the discussion on redundancy. Attached is a diagram of a scaled architecture (specifically calculated to get a response on this site).
![[Smile]](smile.gif)
[ 21. January 2003, 17:56: Message edited by: Irving ]
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Frances
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posted 21. January 2003 20:48
Interesting approach but I would like to ask you some questios. Are you suggesting that RM&NS worked on every single component of this leaf to shape it the way it is or is the suggestion that a simple building rule can lead to some intricate structures?
The rule to generate a Fibonacci sequence found in leaves hardly seems to argue against RM&NS generating such a rule.
Thus it is not evolution acting on every single step but rather on the genes that determine the growth of the leaf
"We are about to explain that this phenomenon comes not from perfection through evolution (which is, in itself, oxymoronic) but from the dynamics of plant growth."
from library.thinkquest.org/27890/applications5.html
See also Here
quote:
Why do these arrangements occur? In the case of leaf arrangement, or phyllotaxis, some of the cases may be related to maximizing the space for each leaf, or the average amount of light falling on each one. Even a tiny advantage would come to dominate, over many generations. In the case of close-packed leaves in cabbages and succulents the correct arrangement may be crucial for availability of space.
Source
[ 21. January 2003, 20:50: Message edited by: Frances ]
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Irving
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posted 21. January 2003 22:22
Thanks for the reply Frances,
quote:
Interesting approach but I would like to ask you some questions. Are you suggesting that RM&NS worked on every single component of this leaf to shape it the way it is or is the suggestion that a simple building rule can lead to some intricate structures?
Neither. By reading the posts that lead up to this point, you can see that my issue is with scalable design. I don't believe that RM & NS could have produced this architecture by working on every single component. Nor can a simple building rule. What I've attempted to illustrate in the above posts, is that simple building rules "in the real world" are anything but simple.
Are you saying that the entire structure has sprung forth at once? (Sounds a lot like creationim...)
On paper, you can have a simple building rule that just adds structures according to a sequence. In this architecture, the structures are identical, you can't just add identical structures unless the structures were "pre-designed" to allow this type of connection in the first place. At some point the original structure needed to have been developed, prior to the simple rule that dictates the number of them and their positions. If the original structure was developed under RM & NS, then it was developed without any selection pressures dictating the need for future scalability.
I also notice in the links you provided, as well as the quote you offered that this issue isn't addressed. Sure there is some speculation regarding the placement, and why the seemingly Fibonacciesque placement may be there...but that misses the critical engineering issue. Complex components don't scale unless they've been designed to scale in the first place.
quote:
The rule to generate a Fibonacci sequence found in leaves hardly seems to argue against RM&NS generating such a rule.
Maybe, but the fact that a rule can use a Fibonacci sequence to generate an architecture does argue against RM & NS.
[ 21. January 2003, 22:25: Message edited by: Irving ]
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RBH
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posted 21. January 2003 22:34
Irving wrote quote:
This places a scaled architecture outside the notional ability of natural selection since the scaling requirement is outside the selection space during the development of the original component. Therefore I suggest that it is improbable that scaled architectures can be created via random mutation and natural selection (RM & NS); hence scaled architectures are an example of Specified Complexity.
Leaving aside the question of "specified," the leaf shown appears to be the product of an "L-system," or Lindenmayer system. Such representations - scaled architectures - are evolvable, at least in computer-based evolutionary algorithms. See this page for an example. Clearly all the usual questions about the source of the fitness function and so on arise once again, but leaving that aside, Hornby says that quote:
We describe a system for creating generative specifications capable of hierarchical regularity by using Lindenmayer systems (L-systems) as the generative representation for an evolutionary algorithms. Using this system we demonstrate a system that evolves hierarchically modular tables and locomoting robots (called genobots).
I don't here wish to argue the fitness function business again - that's another thread, one that exists on ARN and here in places. The point is, though, that a model of an evolutionary process can produce what Hornby calls "hierarchically modular" structures that sure look like a scaled architecture.
RBH
Added in edit: Hornby's thesis abstract includes this: quote:
Using this system, a non-generative and a generative representation are compared on four classes of designs: three-dimensional static structures constructed from voxels; neural networks; actuated robots controlled by oscillator networks; and neural network controlled robots. Results from evolving designs in these substrates show that the evolutionary design system is capable of finding solutions of higher fitness with the generative representation than with the non-generative representation. This improved performance is shown to be a result of the generative representation's ability to capture intrinsic properties of the search space and its ability to reuse parts of the encoding in constructing designs. By capturing design dependencies in its structure, variation operators are more likely to be successful with a generative representation than with a non-generative representation. Second, reuse of data elements in encoded designs improves the ability of an evolutionary algorithm to search large design spaces.
A question here is similar to that Janitor raises periodically, the mapping or representation problem. It appears that a generative representation, as Hornby calls it, enables scaled architectures to evolve.
[ 21. January 2003, 22:45: Message edited by: RBH ]
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Irving
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posted 21. January 2003 22:58
Thanks RBH for the reply, but I believe your referrences again miss the point, L-systems and generative representations are all about evolving the layout, or footprint design not the integration issue.
quote:
A question here is similar to that Janitor raises periodically, the mapping or representation problem. It appears that a generative representation, as Hornby calls it, enables scaled architectures to evolve.
Generative representation allows the architecture using scalable components to evolve, but not the scalable component.
[ 21. January 2003, 23:19: Message edited by: Irving ]
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Frances
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posted 22. January 2003 02:03
Irving
quote:
Maybe, but the fact that a rule can use a Fibonacci sequence to generate an architecture does argue against RM & NS.
Not if the rule is selectable. Fibonacci series in nature seem very selectable since they optimize leaf layout for instance. I fail to see how a rule argues against RM&NS. Are you saying that these structures arose in one swoop or through fine tuning of the 'rule'?
[quote]
Generative representation allows the architecture using scalable components to evolve, but not the scalable component.
[quote]
And what is the relevance of this? Perhaps I am not understanding your arguments.
[ 22. January 2003, 02:05: Message edited by: Frances ]
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Irving
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posted 22. January 2003 07:30
Hi Frances,
quote:
quote:
Generative representation allows the architecture using scalable components to evolve, but not the scalable component.
And what is the relevance of this? Perhaps I am not understanding your arguments.
I'd hoped to develop this a little more slowly, since I was just thinking about this concept in relation to the topic kyle7 posted for this thread.
If you go back a few posts to the post containing the circuit board picture, and maybe a few before it, I've attempted to illustrate that scalable architectures are only possible with scalable components. The rule idea, as well as the computer model RBH has suggested deal with the arrangement of components, or how they scale. Not the inherent attribute of scalability designed into the component in the first place.
In addition to this issue, if you look at my diagram again you'll also notice that not only is the architecture scaled using a replicated component, but that the component itself is scaled!
An aside question...it seems in order to get a discussion going (a debate it seems) every information, complexity, and design issue has to be placed in opposition to evolution. Why is that?
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