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Author
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Topic: A sequence of tests for IC
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gedanken
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Member # 594
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posted 16. March 2003 04:09
In this thread I propose that varying tests and definitions of “Irreducible Complexity” or “IC” be stated.
The notion of “Irreducible Complexity” is one that contains considerable subtlety. Aspects of the definition and of potential tests for “IC” have been argued over for years now. Various presentations of the notion of IC have been given, and aspects have changed or been clarified over the years. Because of the subtlety I propose a need for aggregation in one place of clear descriptions of individual IC tests and definitions.
It is my contention that arguments about irreducible complexity bounce around as different terms are pulled out from widely varying literature for examination. But because there is no single consistent aggregation of specific and clearly written tests for IC, these arguments never seem to settle anything. (This does not mean that there are not consistent intuitive notions that have endured -- simply that these have been written in varying ways subject to varying interpretations.) It is my contention that producing compactly written and clear definitions and descriptions of the tests for IC would be helpful in such arguments, because a clear definition or description of a test could then be pointed to.
Now there have been several discussions of IC on varying threads, wherein the notions of IC have been refined and changed. This thread is intended to have a strikingly different aspect:
I propose that there is not a single definition or test for IC. Rather there have been a sequence of such definitions or tests, and that any one of those definitions or tests may have a useful purpose. That does not preclude the usefulness of a different test or definition in another situation.
So the “prime directive” in this thread is that different definitions of and tests for IC be developed, but that each individual definition be given in sufficient clarity all in one place to be useful in a stand-alone manner. Definitions or defined “tests” for IC in this thread should not have the notion that varying points made in the literature may be brought up at the authors will. Rather the major tenets of the particular definition or test for IC should be placed in one place, within a single post in each case.
Now I’m not saying that every word of the definition or test must be quoted within the single post. Rather that the single post should outline in unambiguous terminology what definition is being listed -- and provide clear references to exact literature (preferably online) for any auxiliary material necessary. External literature must be cited by exact page number and standard reference terminology.
The second major point is that each definition or test for IC should be given a number. Each author giving a new definition of IC is requested to number the definition from the previous post containing a definition. As authors post their definitions, we can simply number in sequence. It is my contention that there is nothing wrong with different tests for IC, any more than there is anything wrong with multiple scientific tests being described for any particular theory. Some definitions may fail to be useful. Others may clarify problems and be more useful. The point is to clarify the distinction between these different tests, and to name the individual clearly identified tests so they can be clearly identified. (At minimum we shall name them by numbering them.)
In this way a given case considered “IC” being discussed in any thread can point to the individual test presented here. By pointing to which particular definition of IC or test for IC is under consideration, lack of clarity of argument can be avoided. And because multiple definitions and tests are given, the failure of a particular test to be relevant to a particular case in question is not a negative. Rather the list of tests can be considered in sequence, in an exhaustive manner. And if a new test needs to be developed for a new situation to be examined, then a new version can be added to this list and given the next number in sequence.
It is this differentiation of the different definitions or tests for IC that differentiates this thread from other threads on the subject. The concept is not successive refinement (which may occur), but rather clarity of the individual definition including distinction from others. When we have successive refinement over multiple pages, the individual characteristics of the individual clearly stated test are diluted -- it is better that a new definition (with a new number in this thread) be developed, rather than a diffuse definition or test be given that cannot be pointed to as a single concise entity.
Now I would propose that the normal rules apply in this thread. No criticism of any definition of IC should be given on the first page -- save a single very mild one: That another definition has been given elsewhere in the literature. The mild criticism that a different definition has been given should be allowed on the first page, simply to identify a need to gather together this different definition or test, so as to help clarify that these distinctions exist.
Also I hope that the moderators will allow that I don’t present an actual definition or test myself, as I feel this is outside of my expertise. I am identifying a need for this work, and hope this is sufficient for establishment of this thread.
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yersinia
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posted 16. March 2003 05:01
One suggestion: every variation of "IC" definitions should be indented in quotes and given a title for ease of reference.
E.g.:
quote:
Multiple-parts required IC
A system is IC wrt function X if all the parts of that system are required for function X.
I know that the original Behe definition includes "well-matched" and "interacting" but in practice these are often left out and don't really even play a role in the IC-->ID argument, which is always based on the presence or absence of parts.
I don't have the quotes handy but published definitions should probably be posted and referred to by references, e.g. the Behe (1996) definition, etc.
[ 16. March 2003, 05:02: Message edited by: yersinia ]
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Micah Sparacio
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posted 16. March 2003 09:54
Some original definitions:
Taken from the ISCID Encyclopedia entry on Irreducible Complexity
Behe's Original Definition:
MP-1
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)
Dembski's Enhanced Definition:
MP-2
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)
[ 16. March 2003, 10:08: Message edited by: Micah Sparacio ]
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Micah Sparacio
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posted 16. March 2003 10:06
I think that Nic's post is important. We need to distinguish between what Lakatos calls the "hard core" of a theory and the periphery. In giving these definitions, many are going to have the same "hard core" (Nic points out that one such "hard core" is "Multiple parts IC." There will be a large number of variations on this general category.
Perhaps we can invite both specific definitions as well as general categories of definitions. Then we could use a number system as follows
Category-Number
(MP=multiple part category)
MP-1
MP-2
etc.
(CS=construction sequence category)
(CW=Complex whole category)
So while most of the definitions will be variations on the MP theme, some definitions may emphasize the construction sequence of a system while other definitions may emphasize not the multiple parts of the system but the general complexity of the whole, single system.
Anyway, these are just some thoughts to play around with.
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Art
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Member # 179
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posted 16. March 2003 11:07
quote:
Dembski's Enhanced Definition:
MP-2
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)
It's probably been mentioned before, but does anyone else have a problem with the phrase "such that each part in the set is indispensable to maintaining the system's basic, and therefore original, function"? For example, doesn't this rule out co-ooption out of hand, before the question can even be asked? At the very least, it makes any useful conclusion of IC almost impossible to come by, since "original function" is an endlessly ambiguous concept.
Wouldn't "such that each part in the set is indispensable to maintaining the system's function" be a big improvement?
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gedanken
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Member # 594
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posted 16. March 2003 13:20
I would like to emphasize the aspect of a “test” for IC again. We need more than just a definition, in my opinion. We need more detail on how to actually evaluate a case.
The reason I bring this up is some discussions I was recently in, in which cases were supposedly shown to be or not be IC because evolutionary pathways were suggested in terms of co-option or variations on the function. These were given as demonstration that the case was not IC. But I don’t see how the simple definitions given capture this issue. I would like the greater test to be explained well enough that one can make an objective determination in a given case to which the particular “test” applies. (And “test” is the application of the definition, I presume, along with sufficient descriptive materials to at least narrow down caveat’s for example. I would like to know how one actually tests for the given definition of IC.)
Also is the issue of irreducible complexity and the “core” having two aspects: “irreducibility” and “complexity”. It would be helpful of these aspects were defined more completely in the given definition, for example is “complexity” Dembskian complexity meaning low probability? (If so this may interact with intended aspects of objective evaluation, for example -- so please specify. Remember that there is nothing wrong with multiple definitions, for example we could take a single primary definition and break it out into multiple overview definitions by substituting different definitions of ‘complexity’.
Also let’s start giving numbers. So far I shall label:
#1 = MP-1
#2 = MP-2
As given above, no additional explanations attached. (Thus we have a new definition, for example, if someone combines MP-2 with a given definition of complexity, or whatever is deemed important.)
--
Sorry, I like Micah's classification scheme just fine. (I had missed a detail.) Only use my added sequence #s if there becomes a clarity problem. For now let's stick to Micah's numbering scheme. MP-? enhanced definitons are just new MP #s.
[ 16. March 2003, 15:59: Message edited by: gedanken ]
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Cre8ionist
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Member # 140
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posted 16. March 2003 21:32
Hey,
Just wanted to comment on the testing part, my thoughts on the definition are already in the encyclopedia thread.
One way to potentially falsify a particular case of IC is to demonstrate that it is really a case of cumulative complexity rather than a case of IC.
Dembski said (and btw Micah, you may want to add cumulative complexity to the encyclopedia),
"A system is cumulatively complex if the components of the system can be arranged sequentially so that the successive removal of components never leads to the complete loss of function." (Intelligent Design, p 147)
Obviously due to the law of non-contradiction something can't be both cumulatively complex and irreducibly complex at the same time, by definition.
An example of cumulative complexity I've used is a bow and arrow. Its components can be removed one at a time without losing the function.
Example: The system is three parts, a bow, string and arrow.
Function: launching arrow
Remove the bow and the string can still be used to launch the arrow as a sling.
Remove the string and the arrow can still be used as a spear, therefore the bow and arrow is a cumulatively complex system. In other words, if someone claims that the bow and arrow is an IC system, this claim could safely be rejected.
Now contrast this to what's been used to try and falsify the idea that the bacterial flagellum is IC and you'll see that there's a long way to go before you can say that the flagellum is cumulatively complex.
One side-note for those who are interested, Professor John McDonald tried to show that Behe's mousetrap was cumulatively complex, but Behe showed that this wasn't so.
Here's Behe's response to McDonald (it also contains a link to the original McDonald page)..................................Cre8
[ 16. March 2003, 21:34: Message edited by: Cre8ionist ]
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gedanken
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posted 16. March 2003 22:37
Cre8, can this be reduced to a "test" or "definition" that can be posted here, or at least precisely define the definition as precise sections of linked references? I'm trying to gather together possible "tests" that can be enumerated, so they can be considered individually and exhaustively. Reverences to a generally here sort of description are helpful, but are not yet at the level of precision I am trying to get written.
[ 16. March 2003, 23:11: Message edited by: gedanken ]
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Cre8ionist
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posted 16. March 2003 23:52
What exactly is wrong with the cumulative complexity test?
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gedanken
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posted 17. March 2003 02:15
quote:
Obviously due to the law of non-contradiction something can't be both cumulatively complex and irreducibly complex at the same time, by definition.
I intend no criticism of the cumulative complexity test, and find this definition to be very useful to our task.
But I also want a definition of IC. It can't be "obvious" that we have an application of the "law of non-contradiction" if I don't have a clearly specified definition of IC to which I can examine and determine if there would be a contradiction.
So I see this as perfectly fine:
New definition of IC: Definition X (choose from past or future) and additionally it must not be "cumulative complexity".
This definition would then never contradict this new IC and also be "cumulative complexity".
Short of such a definition that inherently excludes cumulative complexity, please give a definition of IC itself. (And if necessary give a discussion of precisely what term of that definition makes cumulative complexity necessarily not IC.)
I would like to reiterate a comment I made in opening this thread, that one form of mild criticism might be meaningful on the first page: "That another definition has been given elsewhere in the literature." I hope this is taken in that general spirit, in that I think we are on the edge of something useful here in producing another definition of IC.
One could say, for example that the definition of "cumulative complexity" is a useful adjunct to definitions of IC. For example any definition of IC for which can be shown by logical derivation to imply negating the precepts of "cumulative complexity", then the "cumulative complexity" test is a useful test for showing that the given IC definition does not apply to the case in question. However the definition of "CC" offered is not in itself a definition of or constraint on definition of IC.
(Then we leave for future arguments the question of which definitions of IC logically contradict CC or vise versa -- e.g. for which definitions of IC the CC test is useful.)
The other possibility is that I mentioned above, of adding contradiction of CC to a given definition of IC so as to form a modified (and possibly strengthened) definition of IC. [ In other words IC’ <==> (~CC & IC) , or “not CC” is added as a precondition to a prior definition of IC. ] Both cases are useful, but only the second actually creates a definition of IC itself.
[ 17. March 2003, 03:01: Message edited by: gedanken ]
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Cre8ionist
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posted 17. March 2003 08:06
Ged,
quote:
It can't be "obvious" that we have an application of the "law of non-contradiction" if I don't have a clearly specified definition of IC to which I can examine and determine if there would be a contradiction.
I should've noted that I was juxtaposing CC with MP-1 & MP-2. I know you're seeking the clearest definition possible, which covers all the bases but this may be a little like having one definiton of evolution as there are different types of IC.
But to complete your request perhaps:
Behe's Original Definition:
MP-1 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.
(CC-1) The components of the system can be arranged sequentially in such a way that the successive removal of components doesn't lead to a loss of function.
Therefore, if CC is demonstrated in a system, IC is falsified in the system.
How this might fit in to your thread I'll leave to you, you're the mini-mod........................Cre8
[ 17. March 2003, 08:07: Message edited by: Cre8ionist ]
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Argon
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posted 17. March 2003 10:48
Cre8ionist writes: ...
quote:
Behe's Original Definition:
MP-1 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.
(CC-1) The components of the system can be arranged sequentially in
such a way that the successive removal of components doesn't lead to a
loss of function.
Therefore, if CC is demonstrated in a system, IC is falsified in the system.
Possibly redundant. Notice the following:
IC = "...the removal of parts causes a loss of function"
CC = "...the removal of any parts does not cause a loss of function"
!CC = IC. If you define one, you define the other automatically.
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gedanken
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posted 17. March 2003 14:17
Cre8 said:
quote:
I should've noted that I was juxtaposing CC with MP-1 & MP-2. I know you're seeking the clearest definition possible, which covers all the bases but this may be a little like having one definition of evolution as there are different types of IC.
Cre8, please read my opening post. I pointed out that I wish to get a large number of different definitions. Micah even proposed a numbering system for entirely different categories of definitions of IC, including:
MP series = multiple part category
CS series = construction sequence category
CW series = Complex whole category
My purpose is two fold. First is exactly the point that you raised -- that a single definition is not sufficient. But the second is to help make the use of these definitions more rigorous. If one changes definition in mid argument, this can lead to logical fallacies because the meaning of terms is not consistent from beginning to end of the specific argument. By having this established set of definitions we can avoid such logical fallacies because the particular definition being used can be referenced here. Additionally we can treat the subject a little more scientifically because we can examine the list of different definitions exhaustively, rather than a vague notion of referring to arbitrary literature, some of which is unknown to others of us.
As to overlap of CC and MP-1 or MP-2, I will leave this to the second page or later, because this is the brainstorming phase. When we get there we can discuss whether or not there is an overlap -- and also the degree to which CC is useful as counterpoint to other definitions.
If you simply want to assert that there is no overlap of CC and either MP-1 or MP-2, we can leave it at that for now, but if you want to propose actual definitions of IC, that would be the target intended of my opening post. I am glad that you brought up CC because I think it will prove useful. Let’s label this as presented by Cre8 (generally considered to not be IC) as CC-1 (in the spirit of Micah’s numbering system):
quote:
CC-1
A system is cumulatively complex if the components of the system can be arranged sequentially so that the successive removal of components never leads to the complete loss of function." (Intelligent Design, p 147)
Argon (and Cre8) I think we need to consider the irreducible core issue as well. MP-2 deals in issues of the “core”. But there will be questions of precisely what “function” is being discussed. There may be more than one single function, and issues will arise in regard to the blurring of lines between functions and of multiple associated functions wherein the “core” is referring to one of those functions. With regard to that, I believe that there may be combinations of MP-2 and “CC-1” that become useful. If someone finds a reference in the literature or wants to propose such a combination we can give it a label, and if not we can reserve that for the future.
Also important is what I read somewhere as defined as “redundant complexity”. Here are a couple of references: Shanks and Joplin on Redundant Complexity, and Behe, a reply on the subject. (PLEASE no discussion of the merits of these contentions here!) What I am looking for is whether some sort of clear definition of IC can be pulled from the discussion surrounding these issues. Rather than simply discussing the merits of different cases in terms of evolvability, has someone actually given an objectively testable definition of IC or test for IC in these discussions relating to the issues? Has someone given a definition or test for IC that distinguishes IC from “redundant complexity” for example? (And is there a definition of “RC-1” that can be given here as well?)
[ 17. March 2003, 14:33: Message edited by: gedanken ]
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gedanken
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posted 17. March 2003 14:47
A REQUEST on brainstorming phase:
I can see that we are going to quickly run out of page 1 of this thread. But I feel that we have not yet accumulated sufficiently clear definitions and tests for IC. I can see the possibility that this thread will have a lively discussion of the merits of these definitions. But first I want to challenge those who have studied IC and have a personal belief in its usefulness to present well reasoned cases here for tests for IC character. (I am not qualified to do so!) Remember that precise references to such reasoned arguments, and narrowly specified here are equally useful -- one does not have to quote the entire text in this thread, just a very precise reference (preferably online).
My request is to continue the brainstorming phase on through page 2 of this thread, so that we can have a chance that the very best concisely written tests for distinguishing IC cases from other cases should be presented here or linked here. (There are plenty of opportunities to challenge the application of those definitions in other threads which then provide links to this thread. Free-for-all discussion will come soon enough.)
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Argon
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posted 17. March 2003 16:28
There is another criteria I've seen:
The amount of ICness in a system is a function of the number of neutral evolutionary steps required to account for its origin by natural mechanisms. The advantage is that ICness is recognized as continuous function rather than as a binary proposition. The disadvantage is that the determination requires data that is often impossible or very difficult to acquire and relies on historical knowledge of precursor states. I suppose this would put it in the Construction Sequence category.
I don't know who originaly proposed this definition but it sounds a lot like what Peter Ruest discussed in the ASA reflector hosted by Calvin College.
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