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Author
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Topic: Nature Refutes ID?: The Evolutionary Origin of Complex Features
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Pim van Meurs
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Member # 541
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posted 22. May 2003 22:46
Roger, could you give me an explanation why well matched would somehow exclude EQU from being IC. Given your comments may I infer that in addition to the knock out criteria there needs to be something called 'well matched' and that you believe that the EQU does not fit this somewhat vague category?
Last time you said
"The parts are "well matched" to the function via ID. The designers of the program picked a limited set of components conducive to the goal of EQU. That isn't anything like a bacterial flagellum in the real world."
Which one is it? Are they well matched or are they not well matched?
Then we may explore the validity of the rest of your comments.
[ 22. May 2003, 22:49: Message edited by: Pim van Meurs ]
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Roger R
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posted 23. May 2003 07:36
quote:
Roger, could you give me an explanation why well matched would somehow exclude EQU from being IC.
Well, if we are gonna go back to prior quotes, we have this from you:
quote:
The basic function seems to be quite clearly EQU and the parts are well natched (sic) and interaction, where each part contribute to its ultimate function.
This was after you quoted the Behe definition including that term. So, you are happy with it when you think it helps your case, and it is expendable when it doesn't.
I don't think an explanation from me of why WM (well-matched) is necessary to being IC, when we have such an admission against interests from you. The complaints here from many who think that the EQU function is IC, is that the definition keeps changing. But when I stick to the original, they are unhappy because they want to reserve for themselves the power to change it when inconvenient to their point.
As to explaining what you think is a contradiction from me, I'm merely pointing out that the selected instruction set is well-matched to the goal of claculating and outputting logical functions. But, with the bacterial flagellum, or any biological example, the Darwinian assumption is that the WM parts evolved. But there are no evolved WM parts here.
Indeed, I believe RBH wants to trumpet the myriad of ways that EQU is built. He seems to think that is an argument against a gradual slope, which it isn't. There can be many paths up Mt [Im]probable. What it is an argument against is that the evolved parts are WM to the EQU function, since there are many ways to achieve the function using the instruction set. And in addition, the subcomponents of the goal themselves are rewarded.
And one last point that I was gonna comment on the first time you said it, but time constraints intruded, is when you say The basic function seems to be quite clearly EQU . The problem with EQU is that by definition, it has no "basic" function, but only an exact deterministic one. We can't have a "less efficient" EQU function in terms of results. We can have a visual system, or a motility system that produces lesser results than other such systems. But EQU being deterministic, it either is or it isn't be definition.
That makes it easy to study, but less applicable to the biological world, and indeed, less friendly to the Darwinian theory itself, which proposes gradual changes and small increments in effectiveness.
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charlie d.
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posted 23. May 2003 08:10
RR:
I don't think Pim was arguing the the EQU parts are not well matched. I think he'd say they are (without putting words in his mouth), because the logical fucntions have to be assembled a certain way to produce the EQU function. I don't know if anyone has done the practical experiment, but I am quite sure, just looking at the fucntions, that swapping instruction lines around in one of the final products would destroy the EQU function. Just like for flagellar properties, each instruction line, each logical operator, has to interact properly with its (computational) neighbors for EQU to be performed.
Pim's point seemed to be that you first said the EQU parts were well matched, and designed to be so, i.e. you appeared to be arguing that EQU was IC, but also ID - the classic "sneaked-in design" objection that was already argued against, for instance, Tom Schneider's simulations (at least, that was my impression of your argument). Now, instead, you seem to be claiming that the parts are not well matched after all and thus the system not IC, while at the same time saying you did not change your argument.
As for the rest of your post, I think the same problem we have been talking about since the beginning of the thread manifests itself once again. That is, there is a lot of fuzzy arguing about definitions. without any attempt at systematic analysis.
I would say at this point that, whether or not EQU is IC, it is even more important to the ID field that the whole concept of IC is demonstrated to have any usefulness and applicability. IOW, people have to be able to look at something they haven't seen before, apply some reasonably standardized methodological approach, lay out their analysis, and come up with an answer: is that thing IC or not.
I for one am quite surprised that most ID advocates here have not even begun to try to do this for EQU, showing how this is supposed be done: how do you identify "parts", how do you say if they are "well matched", how do you define "basic function", how do you demonstrate any part is essential to the function. (Or whatever else you are supposed to do - just do it.)
If scientists are unable to independently and reliably do this systematically, on any object they may encounter in their studies, what good is IC as a research tool, or as a theoretical concept? If all it boils down to is "look at the flagellum, look at the mousetrap" over and over again, what is the rest of us, who are not really so interested in mousetraps or flagella, supposed to do with the whole thing?
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YZ2
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posted 23. May 2003 10:19
I probably need to move on to do other things, so this may be my last comment:
It is interesting to see how quickly ID-evolutionists joined up to improve the theory of design. I think it is important to realise that IC in a design theory is only a working model, just as an evolutionary mechanism in an evolutionary theory is. If you agree with the discussion so far that in the original ID theory, it only says IC predicts ID, and non-IC can be either ID or non-ID, then an non-IC object is irrelevant to the theory of ID. I am no expert in ID, so I think as more observations are gathered, we can come up with a more realistic and clearer definition/method in detecting design. At that time, ID theory can then become a more mature discipline.
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Argon
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posted 23. May 2003 10:23
Roger R writes:
quote:
We can have a visual system, or a motility system that produces lesser results than other such systems. But EQU being deterministic, it either is or it isn't be definition.
This reasoning is the exact opposite of what Behe described in his book. Behe's criteria and examples were presented in DBB as "either/or" scenarios. For example, knock out part of the flagellum and it no longer spins or even assembles. Knock out part of the blood clotting cascade and you've got serious illness and death to worry about from uncontrolled bleeding or inappropriate clotting. The point of all his examples were clear: Remove or damage one part of an IC system and you lose its function. Whether some of the components of one IC system can have a part in another IC system (i.e. may have dual roles) is irrelevant -- That only speaks to the possible evolvability of an IC system or the "efficiency of a designer" that creates multifunctional components, not IC-ness. It is crystal-clear in Behe's book that knock-out and mutation testing is one means of determining the IC-ness of a system.
If you say that components of the flagellum can be knocked-out while retaining at least some of the motility, you are actually demonstrating that the system isn't IC. In other words, the logic couldn't be more completely reversed from Behe's original proposal.
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Micah Sparacio
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posted 23. May 2003 10:24
Off to the hillsides of West Virgina for 9 days. But here are some comments I sent to some of my friends this morning that may be of interest here...
To really understand the Avida programs you've got to understand the architecture. Especially the nature of the registers, stacks and instruction set. If you understand this stuff, it makes tracing the organisms, etc. a whole lot easier. It also keeps you from abstracting too much about "nands" and "EQU" functions. One other thing, always remember that there is a difference between the nand primitive and the "NAND" function which is actually rewarded by the system.
It is the nand primitive that the system absolutely needs to reach and EQU function. It is also important to note, that each and every movement towards higher complexity will involve these steps:
1. Move the data (e.g. X , Y , X or Y ... etc.) into the proper registers
2. Apply a nand
So, what you need for anything to happen is the nand primitive and different operations to move the data around so that the nand can be applied to various data. When a nand is applied to an X in one register and a Y in another register, you get the actual NAND function (Y NAND X). When you nand together two registers that contain say X and (Y nand X) you get (X or ~Y) and so on. Basically, any building of complexity involves the application of a primitive nand to the contents of two registers. All the program really needs to do is find the right set of pushes and pops and swaps, etc. to get the data into the right place before a nand operation takes place. The movement of data and placement of nands is the contingency, but these are really your building blocks that, joined with a nice fitness function make your path to the EQU just a little less than perfectly smooth.
[ 23. May 2003, 10:26: Message edited by: Micah Sparacio ]
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Pim van Meurs
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posted 23. May 2003 14:32
Micah: The movement of data and placement of nands is the contingency, but these are really your building blocks that, joined with a nice fitness function make your path to the EQU just a little less than perfectly smooth.
What is 'little less than perfectly smooth'? Surely the fitness function could hardly be called smooth with some really good jumps and even the fitness assignment itself shows that it is not continuous. And if the fitness function is smooth, how come that most logical functions are quite vulnerable to being knocked out?
You object that it is the nand primitive which is somehow required by the system and all that is needed is an efficient search to find the solution. Well, it seems that RMNS may fit such a requirement and surely it outperforms random search, showing that the No Free Lunch theorems apparantly do not apply here.
let me give you an analogy with the flagellum: There are just basic proteins that have to be placed into the right order, all that is needed for the 'program' is to find the right sequence to generate the proteins and their order. The location of the proteins and the proteins themselves is the contingency but they are really your building blocks that joined with a nice fitness function make your path to a flagellum just a little less than perfectly smooth.
Calculations have shown that the tornado in the junkyard solution does not seem to be a viable pathway but for EQU, there does seem to be several evolutionary pathways.
All we need to establish is: Is EQU IC.
Charlie correctly presents my argument in his response to Roger.
Roger also comments that "But EQU being deterministic, it either is or it isn't be definition."
Which sounds awefully similar to an IC system. If that is not the 'basic function' of EQU and the removal of any part will fully destroy that function then I really don't know what would be IC.
Roger then states that "That makes it easy to study, but less applicable to the biological world, and indeed, less friendly to the Darwinian theory itself, which proposes gradual changes and small increments in effectiveness. "
And yet EQU 'evolved' through such non Darwinian mechanisms as variation (mutation) and selection? Isn't it fascinating how unfriendly EQU is to Darwinian evolution by pretending that it can evolve through exactly these Darwinian mechanisms ![[Wink]](wink.gif)
My question to you is:
initially you said that
quote:
"The parts are "well matched" to the function via ID. The designers of the program picked a limited set of components conducive to the goal of EQU. That isn't anything like a bacterial flagellum in the real world."
now you state that
quote:
That "well matched" is open to some interpretation is true enough, but it is also true that you can't just ignore it and claim "knockout" is the litmus test for IC. "Well matched" is critical to understanding why EQU is not IC, and not analogous to the bacterial flagellum.
You initially seemed to suggest that the EQU was well matched to function although you used the wrong analogy "by ID". Now you seem to argue that Well matched is critical to understanding why EQU is not IC. Are you saying that EQU is well matched but not IC or that EQU is not well matched and not IC or that it is IC but also ID?
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RBH
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posted 23. May 2003 18:17
Just to remind us all of the 'canonical' definitions of irreducible complexity, these are from ISCID's Encyclopedia: quote:
Irreducible Complexity
Michael Behe's Original Definition:
A single system composed of several well-matched, interacting parts that contribute to the basic function of the system, wherein the removal of any one of the parts causes the system to effectively cease functioning. (Darwin's Black Box, 39)
William Dembski's Enhanced Definition:
A system performing a given basic function is irreducibly complex if it includes a set of well-matched, mutually interacting, nonarbitrarily individuated parts such that each part in the set is indispensable to maintaining the system's basic, and therefore original, function. The set of these indispensable parts is known as the irreducible core of the system. (No Free Lunch, 285)
[With a link to "irreducible core"] quote:
Irreducible Core
The parts of a complex system which are indispensable to the basic functioning of the system.
Michael Behe's "Evolutionary" Definition
An irreducibly complex evolutionary pathway is one that contains one or more unselected steps (that is, one or more necessary-but-unselected mutations). The degree of irreducible complexity is the number of unselected steps in the pathway.
The first definition, Behe's original DBB formulation, is clearly an ahistorical one. There is no reference to the past or the pathway to the state of ICness so long as we interpret "basic function" to mean "current function" and assume that a system performs only one function or, if it performs more than one function, we can tell which is "basic." It is also the definition that specifies the operation necessary to classify a system as IC: the knockout procedure. "Interacting" can also be operationally determined by observing correlations between the behaviors of parts. The vagueness is in the term "well-matched." There is no way mentioned in the definition (nor elsewhere in DBB) for 'well-matchedness' to be measured. Hence operationally - that is, experimentally - we have only the knockout procedure and identifying interactions on which to determine IC or not-IC. On Behe's first definition, the programs that evolved to perform EQU meet the two operational criteria - knockout loss of function and interactions. Only the ill-defined "well-matched" stands between the programs and ICness.
Dembski's refinement of Behe's definition introduces two new elements: "basic, and therefore original, function" and "nonarbitrarily individuated parts." The first addition's reference to "original function" introduces history. In order to classify a system as IC we must know that the current function of some system was also its original function. The effect of this move is to definitionally eliminate cooption (which we know to be common in evolution) as a route to an IC system. Hence this definition is restricted to only those systems in which we know cooption did not play a role in the evolution of the system. This definition, in its reference to "irreducible core," preserves the knockout criterion.
The second addition in Dembski's definition is ambiguous. It is a negative prescription ('do not pick parts arbitrarily') but gives no guidance on what is non-arbitrary. In his NFL example of the flagellum, Dembski works with two levels. There's the 'parts of an outboard motor' level - power source, rotor, propellor - and the level of calculation - proteins. There is no clear justification for which level of parts to use for what part (!) of the definition; the choice seems to be arbitrary.
The programs that evolved to perform EQU do not meet Dembski's definition of ICness, since the final function performed by those programs is not the "basic, and therefore original" function. They coopted other functions. While some of those precursor functions are also performed by the final programs, other precursors were sometimes lost along the way. Hence the "original" functions were not always present in the final program.
Behe's "evolutionary" definition also invokes history. It requires that we know the complete pathway by which a candidate IC system evolved, so we can count the number of "unselected steps." This is also interesting for introducing the notion that "irreducible complexity" can take on values other than 0 or 1: "The degree of irreducible complexity is the number of unselected steps in the pathway."
By this "evolutionary" definition the programs that evolved to perform EQU are IC to some degree, since every step on the path to the programs that performed EQU was not "selected." In fact, some steps in at least some of the lineages leading to the final programs were deleterious and hence were selectively disadvantageous - there was selective pressure against them. Hence they display some degree of irreducible complexity.
Thus depending on the definition one chooses, the programs are IC, not IC, or IC to some degree, and we have no guidance in deciding which it is. Therefore unless and until Behe/Dembski, et al settle what IC means, it is useless from the point of view of doing meaningful research.
RBH
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Argon
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posted 24. May 2003 12:06
RBH writes:
quote:
Dembski's refinement of Behe's definition introduces two new elements: "basic, and therefore original, function" and "nonarbitrarily individuated parts." The first addition's reference to "original function" introduces history. In order to classify a system as IC we must know that the current function of some system was also its original function. The effect of this move is to definitionally eliminate cooption (which we know to be common in evolution) as a route to an IC system. Hence this definition is restricted to only those systems in which we know cooption did not play a role in the evolution of the system. This definition, in its reference to "irreducible core," preserves the knockout criterion.
You know, this definition would probably remove things like blood clotting, a large chunk of the immune system, and maybe even parts of the flagellum from the list of IC systems. For example, the blood clotting cascade is composed of numerous proteases that bear striking similarities to other proteases that are both ancestral to the clotting system and which have different "functions" in the cell. Thus the "original function" of most of the components had nothing to do with clotting. Ditto with the immune system. The current functions of flagellar components are mostly propulsion and cell adhesion, but parts of this system might have originated from a protein translocation system or pore. And so the "original functions" of the flagellar system components might not have been the same. How does one actually determine such things in ancient, ubiquitous systems that have undergone strong selection before diversification?
Obviously (to biochemists at least), it's a practical impossibility to be sure of the "original" function of any component. I think Dembski has a Platonic and "separate creation" view of organisms and biology. Ernst Mayr knocks that viewpoint down in a series of books.
In ruling out the possibility of co-opting other components Dembski seems to convert the IC definition into the truism that unevolvable IC systems are unevolvable. After all, does Dembski think that cells acquire large stretches of DNA that spontaneously appear out of nowhere and have no past? Yes, if one wanted to describe a system that had no past as "IC", one could do it. But then that definition would have little to do with the mechanisms by which evolution operates and would thus be orthogonal to the important question of evolvability.
RBH also wrote
quote:
Thus depending on the definition one chooses, the programs are IC, not IC, or IC to some degree, and we have no guidance in deciding which it is. Therefore unless and until Behe/Dembski, et al settle what IC means, it is useless from the point of view of doing meaningful research.
Why should they be the final arbiters of what is and isn't IC? Behe spent plenty of time writing his book and developing his ideas. His whole thesis fundamentally relies upon the abilty to properly identify IC systems. Dembski also had a long time to develop a mathematical "model" of ICness. They have both observed and participated in many discussions about these definitions and the problems associated with their various criteria. They have also given many talks on the subject. Since both men understand the crucial importance of having useable, workable guidelines when performing research, particularly in a new area, I have little doubt that they would have let all these years go by without already presenting all that they could on this subject about the clarifications and important distinctions.
IC was first defined in Behe's book, DBB. As RBH mentions, it was an ahistorical definition. All subsequent changes made by Behe and Dembski require historical knowledge about a system and thus substantially change the nature of evaluation. I cannot see any good reason why these new classifications should bear the "IC" moniker without a subheading to indicate the additional criteria that have been met. For example, it can sometimes be simple to apply Behe's original, operational criteria to determine whether a system is IC. But what this does not tell us is whether such a system was evolvable. Thus we potentially have two classes of IC systems: evolvable or unevolvable. Once a system is determined to be IC, we can now apply additional tests to determine the subclass to which it belongs. Until then it should be placed in a third subclass: "evolvability unknown". Here is how I see the current organization:
Class: IC
* Evolvability status:
* Unknown
* Evolvable
* Criteria type 1: Intermediate steps reproduced.
* Criteria type 2: Similarity to other evolvable systems.
* Criteria type 3: etc....
* Unevolvable
* Criteria type 1: Requires too many "lucky" neutral mutations. (from Behe IC v2)
* Criteria type 2: No possible ancestors. (modification of Dembski IC v2)
* Criteria type 3: Intelligent designer observed.
* etc...
Personally, I'd prefer that the "IC" label be dropped from the subsequent "redefinitions". One possibility: "Unevolvably Complex". I think clever people could invent other, more appropriately descriptive labels that would reflect the actual criteria being applied.
[ 25. May 2003, 10:27: Message edited by: Argon ]
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RBH
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posted 25. May 2003 18:00
I have been informed by a correspondent that I am misinterpreting Dembski's use of "basic, and therefore original function" as having a historical reference. In a thread here on ISCID last year, Dembski said quote:
I wrote, "Please show me in Michael Behe's writings or my own where we deny that IC systems can be made up of subsystems that can be functional in their own right." Both Behe and I have always defined IC with reference to the basic function of the system in question (if we've not said it explicitly -- and I have in NFL -- then a charitable reading would have granted that -- neither Behe nor I are that stupid). We therefore left open the possibility of subsystems having function in their own right.
Thus Dembski's conception of IC is not apparently does not require that the function performed by the 'final' system be the same as the function(s) performed by precursors, and does not rule out cooption. Given that revised interpretation, the programs evolved in Avida to perform EQU were indeed irreducibly complex, since by the knockout criterion they all have an irreducible core.
So the tally shows that the programs evolved in the Avida simulations are IC by Behe's original definition, IC by Dembski's revised definition, and IC to some degree by Behe's evolutionary definition.
RBH
[ 25. May 2003, 18:08: Message edited by: RBH ]
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RBH
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posted 25. May 2003 18:24
Hmmm. Rereading more of Dembski's postings on the thread referenced above, it's slipperier than I first thought, trying to pin down his IC definition. In a posting of Dembski's earlier than the one I quoted above is this paragraph quote:
You've charged me with moving the goalposts and adjusting the definition of irreducible complexity because I require of evolutionary biologists to "connect the dots" in a causally convincing way. The dots here are functional precursors that could conceivably have evolved into the final system of interest. You state that previously I claimed that the dots couldn't exist because they wouldn't be functional. Please show me in Michael Behe's writings or my own where we deny that IC systems can be made up of subsystems that can be functional in their own right. The point is not whether subsystems can be functional on their own but whether they can exhibit the same function in the same manner as the system in question. You misrepresent our position. (Emphasis added)
Shucks. There it looks like the precursor subsystems do have to perform the same function as the final system. Shoot, I don't know. Which is it? Any IDists out there know? Does this IC concept have a definition that's not written in sand and that can be operationalized, or is it just so much bafflegab?
RBH
[ 25. May 2003, 18:28: Message edited by: RBH ]
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YZ2
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posted 26. May 2003 10:06
I have been doing some gardening during the weekend and I have not touched my computer all the time. (Hey, it is a beautiful world out there!) However, this idea is too wonderful to keep it to myself.
To understand how to define IC, we can get some insights from this EQU experiment. Perhaps this may become a classic example of how ID can be detected, as well as its link to IC. As explained by Micah, EQU can be looked at as a sequence (or a string as RBH liked to call it) of applying NAND at certain crucial moments. When these crucial moments fit certain criterion, EQU appears.
Imagine a similar scenario of an observer watching the lights of a Christmas tree. Unaware of what happens, a child behind the wall turns the light switch on and off in a playful way. There is only one action applies to each moment and the lights on the tree become a haphazard sequence of an interesting event to be studied. At this point behind the wall, a musician comes along, takes over the child’s action and beginning to switch the lights on and off according to the rhythm of Beethoven’s 5th symphony. For someone who do not like classical music, the sequence is just as meaningless as the original sequence. There is no IC, no detection of ID, even though the event is designed. However, for music lovers, suddenly it dawns on him that it is a beautiful sequence following the symphony’s notes. Each note is as irreducible as it can be. The whole sequence is IC and the event is completely designed.
What I am saying is that, detecting IC and ID is a co-discovering process. The operational definition of IC depends on ID. That is probably the reason why Behe uses the flexible description of “well-matched” parts. The “well-matched” parts can be interpreted only in the context of recognizing ID. It is a recurrent definition in some way but this is not new. It also confirms the strong link between IC and ID. The “well-matched” parts of EQU when ID is recognized are the NANDs. They are irreducible. The whole sequence forms the IC of EQU. On the other hand, if no one recognizes it is EQU, that is, it is as undefined as any other sequences, then each NAND is reducible and the whole sequence is not IC and no ID is detected.
[ 26. May 2003, 13:26: Message edited by: YZ2 ]
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RBH
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posted 26. May 2003 13:38
YZ2 wrote quote:
To understand how to define IC, we can get some insights from this EQU experiment. Perhaps this may become a classic example of how ID can be detected, as well as its link to IC. As explained by Micah, EQU can be looked at as a sequence (or a string as RBH liked to call it) of applying NAND at certain crucial moments. When these crucial moments fit certain criterion, EQU appears.
This, of course, ignores the fact that the assembly language programs - the sequences of primitive instructions - that evolved to perform EQU in the simulations were not designed. EQU, the logical operation, was not what evolved in the simulations. What evolved were 23 different programs that perform EQU (plus 124 more such programs in a control condition). This is a distinction that seems to be blurred in this thread, but it is critical to understanding what the experiment shows. The abstract logic function did not evolve; what evolved were programs that perform that function. It is those evolved structures - integrated sequences of instructions - that are irreducibly complex as determined by the operational criteria we are given by Behe and Dembski.
The question that Behe and Dembski raised was 'Can those kinds of structures evolve by the mechanisms that evolutionary theory invokes?' Behe and Dembski do not claim that bacterial motility is irreducibly complex, they claim that the flagellum that performs the function of motility is irreducibly complex. Behe and Dembski claim that irreducibly complex structures cannot evolve, or at least are very very unlikely to evolve. But the reported experiment shows that irreducibly complex structures can evolve with high probability, where "irreducibly complex" is operationally defined by the classification criteria Behe and Dembski themselves supply.
YZ2's redefinition, citing Micah, ignores the fact that the occurrence of NAND "at certain crucial moments" is not itself sufficient to perform EQU. It is a whole integrated sequence of instructions that performs EQU, not occurrences of NAND. And it is an integrated sequence of instructions, ranging from 17 to 43 instructions in the "irreducible core", that is irreducibly complex by the operational criteria we are given by Behe and Dembski. In fact, in the example program in the paper (Figure 4) the NAND command primitive actually appears six times, once more than the five that is the minimum necessary to perform EQU. That program is in some sense more complicated than necessary by design.
YZ2 further identifies the "operational" definition of irreducible complexity with the recognition of a pattern by some appropriately knowledgeable observer. As I understand it, that is essentially the definition of "specified" in Dembski's specified complexity, and it suffers from the same problems of subjectivity as does specified complexity. In YZ2's example of lights flashing, the classification of the sequence of flashes as IC or not-IC depends wholly on the subjective judgement of the observer, not on any independently measurable properties of the sequence. That is not a useful operational criterion.
A more technical observation is necessary, too. The existence of the NAND assembly language instruction - the NAND primitive - in the instruction set is insufficient for the program to perform even the NAND logic operation. Performing the NAND logic operation requires additional primitive commands, appropriately sequenced, surrounding the NAND primitive. An example sequence of primitives used by the system to perform the NAND logic operation (Figure 1) is nand, nop-A, IO, nop-A, where the first two instructions perform NAND and the last two communicate the result to the 'outside world.' What does YZ2 consider to be IC? Is it the NAND primitive of the command language; or the sequence of two instructions that performs the logic operation NAND; or the sequence of four instructions that perform NAND and communicate the result; or the whole integrated sequence of instructions that performs EQU? At what level of analysis does the term "irreducibly complex" apply?
Finally, YZ2 wrote quote:
What I am saying is that, detecting IC and ID is a co-discovering process. The operational definition of IC depends on ID.
But that completely begs the question. Behe and Dembski offer ICness as evidence for intelligent design, so to define IC as depending on ID guts their claim that design can be detected empirically. It becomes a definitional tautology rather than a (claimed) empirical hypothesis.
It seems to me that YZ2's redefinition of IC further muddies already murky definitional waters.
RBH
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YZ2
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posted 26. May 2003 14:18
Briefly, two points:
The behaviour of each of the EQU programs using the registers is already quite clear. They are just different partitions of the problem subspaces with the application of an existing NAND on the content of the registers. No more, no less. Without the logical meaning of EQU, the programs are as meaningless as random strings.
IC is a working model to a design theory, just as an evolutionary mechanism is to an evolutionary theory. Has anyone a full description of the mechanism of evolution?
[ 26. May 2003, 15:15: Message edited by: YZ2 ]
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YZ2
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posted 26. May 2003 14:38
One more point:
Nobody claims that the observer defines design in the Beethoven's fifth experiment. The musician defines it (not the child). The observer estimates (or detects) it.
[ 26. May 2003, 14:45: Message edited by: YZ2 ]
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