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Author
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Topic: A sequence of tests for IC
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Daniel Edington
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Member # 421
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posted 29. March 2003 23:18
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Why is it that the possibility for design would depend on the feasibility of evolutionary pathways? What about design through evolution for instance? Furthermore, why do you suggest that design would be non-naturalistic? In fact although design is proposed to be by some to be a replacement to methodological naturalism, it seems so far unable to differentiate itself from it. Michael Murray in "Natural providence (or design trouble)" shows how ID fails in this aspect.
Good questions! But, I don’t know the answers to them Frances. I didn’t make up this Intelligent Design stuff and no one really seems interested in answering questions unless you seem willing to believe up front.
Why not design through evolution? Intelligent Design seems to me to be directed toward proving evolutionary mechanisms impossible. Which is fine, but doesn’t that also eliminate the so-called “front loaded” design idea. Let’s just say that natural law precludes the bacterial flagellum from developing via an evolutionary mechanism. If this is true then how could some Intelligent Designer have used an evolutionary mechanism to create the flagellum without suspending said natural laws? If we are going to resort of suspension of natural laws then we are definitely going beyond “methodological naturalism” here. Or maybe IC just makes the evolution of the flagellum very unlikely. This is ok but, one would think that if the evolution of the flagellum was pre-ordained by some intelligence that the evolution of the flagellum from some precursor without it would be highly likely. In fact I would think that the more likely it became, the more tell-tale of design it might look. Contrary to my intuition, most ID theorists seem to take the opposite stance. Sorry I can’t offer any more of an answer (if you can consider additional questions an answer) to your questions than this, but I’m probably just as lost as you are.
I’m wondering if the debate should be about whether or not the flagellum developed via an evolutionary mechanism or not. Or, if the debate is supposed to be whether or not that evolutionary mechanism was the result of some sort of intelligent direction.
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My concern with ID is as you mention that it does seem to limit itself to formulation rejection scenarios. But that again makes ID not much different from methodological naturalism either.
Maybe, I think it depends on what ID theorist you ask and probably how you ask them.
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gedanken
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Member # 594
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posted 30. March 2003 18:43
I wanted very very much to stay away from "design" in this thread, unless a specific definition is given that incorporates design therein.
Logical details of evolutionary pathways that fit tests given would be interesting. (I want to keep this thread away from two things: extended debates on actual biological cases -- which can simply be referred to a thread about the specific case; and 'design' inferences that are not specifically part of the direct and immediate implication of the definitions and tests.)
For example if someone has a biological case of a pathway, one could write up an abstract description (not specific to the case, but using steps as described in a test or describing the quality that needs to be addressed and is missing in a test). One could then link to the thread with the actual case, and here argue the issue of the logical pathway of sequence of steps, like if these steps occurred, would the definition x or text x-test-y be met?
I haven't had time to think about it, but I think that MP-2 for example (and all tests given for MP-2) don't disallow some selected but slightly indirect evolutionary pathways. And this appears to be the case without even bringing up the issues of cooption and fuzzy "function" definitions yet. I want to go thorough that case first because it has the same structure as the fuzzy "function" def case, and the cooption case, and yet is in terms of the simple terms of the tests given.
Then we can see what hidden additions were in the "fine print" that need to be added to the basic definition to really come up with what has been intended for MP-2 (and more realistic or complete tests for MP-2 'extended'). I will be interested if the extended version has a test that terminates, or if it changes to the form of an "argument from ignorance". Sorry I don't have more time at the moment.
[ 05. April 2003, 21:45: Message edited by: gedanken ]
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Janitor@MIT
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posted 31. March 2003 15:12
What might a flagellum evolve into? Try to answer the question w/o making any “argument from design” and please be precise.
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gedanken
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Member # 594
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posted 05. April 2003 21:36
In the Organisms using GAs vs. Organisms being built by GAs thread (this link may work) Alonso said:
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With respect to showing IC definitions are functionally equivalent, I have done this several times already in the Sequence of Tests thread, Evolving Inventions thread, and over at the List of IC systems Thread where I compared the precise language of Dembski's definition with Behe's original definition. For example, you can see Behe talk about an IC core with respect to the blood clotting cascade. He didn't mention any of the other factors, but only a few. I really don't see a difference between any of the definitions.
What I am interested in is pushing forward in precise description of generalized tests for IC.
Now to show that definitions are “functionally equivalent” one would have to deal in specifics of the logic of the definitions. It would not be sufficient to deal in a specific case and claim an analogy, because many aspects could easily be left out of an analogy. That is why I have asked for details in this thread. But by details I mean logical clarity along with generality, not focus on a specific case. If two definitions are equivalent, then a single test can be given that tests for both definitions. Baring that, the definitions are not equivalent. (Now since tests given here generally don’t cover all cases of a definition, rather passing the test would be specific instances of meeting the definition, having a given test for two definitions does not imply that the definitions are equivalent. However if the definitions are equivalent, then one can demonstrate that a test for one is a test for the other. This could be done on a purely logical level -- by deductive process. To do a deductive process terms have to be precise, tests have to be posed in precise language that is unambiguous.)
We have very specific problems in some of the tests that were proposed for some of the definitions. The problem is that the test is not one that specifically terminates in a finite (or reasonable) period of time. If no scientist could develop an actual laboratory (empirical) test for a case from the logical-level test given because even at the logical level the test cannot be completed within the lifetime of scientists, it is not a valid test. If a definition has no valid tests, it cannot be (for example) equivalent to a definition that has such terminating tests. For if it were equivalent, it would also have terminating tests.
Also I have asked a number of questions above on basic clarification of basic definitions. (See page 3 or here for page 3) These relate to issues that will be brought up in the future dealing with co-option (treated at the logical level, and not in terms of specific cases). If no expert on IC definitions can even answer these questions, how can they say that IC is clearly and unambiguously defined?
[ 06. April 2003, 00:57: Message edited by: gedanken ]
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Daniel Edington
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posted 06. April 2003 11:25
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Now to show that definitions are “functionally equivalent” one would have to deal in specifics of the logic of the definitions.
Yes. In that sense not all definitions are the same.
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This could be done on a purely logical level -- by deductive process. To do a deductive process terms have to be precise, tests have to be posed in precise language that is unambiguous.)
Again I agree. Toward that end I am attempting to tweak my definition of IC to be precise as possible.
Here is the latest version:
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IC definition:
If it can be shown that the Darwinian mechanism lacks the capacity to connect a biological organism containing a system (any system) to an evolutionary precursor lacking that system, then that system is said to be Irreducibly Complex (IC). A connection would be considered to exist if it can be shown that a series of transitional forms are possible. In this case the term transitional form represents just one in a series of forms, with each transitional form being a successive, slight modification to the previous transitional form.
I offer this modified (and hopefully improved) definition up for critisim.
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Also I have asked a number of questions above on basic clarification of basic definitions…If no expert on IC definitions can even answer these questions, how can they say that IC is clearly and unambiguously defined?
Again I agree with you. If no one can answer such question then obviously IC is not clearly defined. Let’s sit back and see if any answers are forthcoming.
By the way, exactly what does it take to be considered an expert on IC definitions? Who are these experts?
Dan
[ 06. April 2003, 11:32: Message edited by: Daniel Edington ]
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gedanken
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Member # 594
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posted 09. April 2003 22:32
I told Alonso that I would respond to one of his posts referring to this thread in this thread. But upon reading the last posts, I prefer to leave this as it stands. I'll respond later if the issues arise here. I specifically refer the reader to my previous post just above.
One point I would make is that Alonso said that he would call his definition "MP-3", but it was unclear what that definition was. I would ask that Alonso make that definition clear in the way we have been offering definitions.
[ 10. April 2003, 00:38: Message edited by: gedanken ]
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RBH
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Member # 380
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posted 09. April 2003 23:33
Daniel proposed a new definition of IC: quote:
If it can be shown that the Darwinian mechanism lacks the capacity to connect a biological organism containing a system (any system) to an evolutionary precursor lacking that system, then that system is said to be Irreducibly Complex (IC). A connection would be considered to exist if it can be shown that a series of transitional forms are possible. In this case the term transitional form represents just one in a series of forms, with each transitional form being a successive, slight modification to the previous transitional form.
This is a major change in the notion of ICness. It shifts the focus from properties of the putatively IC system itself, generally defined by one or another sort of component knockout test, to the question of the evolutionary emergence of the system.
It does have two attractive features to an ID critic, though. First, one only has to demonstrate the possibility of an evolutionary pathway via plausible transitional forms to negate an assignment of IC status to a system. The "test" for ICness would depend on the imagination of the theorist, not the laboratory of the experimentalist or the field of the naturalist or fossil hunter.
Second, it makes it very clear that ICness is at base an argument from ignorance. What is an IC system today because we can't conceive of a possible pathway can instantly become a non-IC system tomorrow when some enterprising grad student either thinks one up or actually finds an intermediate form.
Of course, there are some fuzzy places - "slight modification" is one, reminiscent of Dembski's "baby steps." Are the rearrangements of genes that occur in recombination "slight"? Does "slight" refer to the phenotype exposed to selection or the genetic combinations that are reproduced because their phene was selected? And "Darwinian mechanism" in the singular needs thought. But those are quibbles. And I assume that identifying a plausible transitional form between two known stages wouldn't immediately lead to the claim that the presence of the transitional form only creates two new gaps that now have to be filled, would it?
I'm sorry if the tone of this seems harsh, but I really think that definition is a step backwards for ID.
RBH
[ 09. April 2003, 23:42: Message edited by: RBH ]
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gedanken
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posted 10. April 2003 00:43
Daniel's definition is almost like Behe's EP-1 (back on page 2). It differs in making the intention explicit, rather than leaving an assumption that "unselected" means of too low probability to be considered reasonable explanation.
Another note of Behe's EP-1 is that the description was in terms of a single pathway. No consideration was given of the impracticality of analysing all pathways. (And of course there is no way I know of to show that one has analyzed all pathways in EP-1 for being "selected", any more than Daniel's more general consideration which has the exact same property except for the assumption given above.)
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Daniel Edington
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posted 10. April 2003 09:06
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It does have two attractive features to an ID critic, though. First, one only has to demonstrate the possibility of an evolutionary pathway via plausible transitional forms to negate an assignment of IC status to a system. The "test" for ICness would depend on the imagination of the theorist, not the laboratory of the experimentalist or the field of the naturalist or fossil hunter.
This is admittedly a weakness of this definition. I was however faced with one problem. While I would have liked to say that the test for ICness depended on some experiment or observation, I was unable to come up with one. To say that proving an IC system depends on proving that an intermediate form exists, or even did exist, isn’t really a valid test. For the simple reason that just because an intermediate existed in the past doesn’t mean that it still exists today, or that there is any evidence for it having existed.
I settled for the idea that proving that the intermediate form was or was not possible as something of a compromise. But, if anyone can come up with a better test I am willing to listen.
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Second, it makes it very clear that ICness is at base an argument from ignorance. What is an IC system today because we can't conceive of a possible pathway can instantly become a non-IC system tomorrow when some enterprising grad student either thinks one up or actually finds an intermediate form.
I would take more than thinking one up. Just because you can imagine it doesn’t mean it is possible.
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Of course, there are some fuzzy places - "slight modification" is one, reminiscent of Dembski's "baby steps." Are the rearrangements of genes that occur in recombination "slight"? Does "slight" refer to the phenotype exposed to selection or the genetic combinations that are reproduced because their phene was selected? And "Darwinian mechanism" in the singular needs thought. But those are quibbles. And I assume that identifying a plausible transitional form between two known stages wouldn't immediately lead to the claim that the presence of the transitional form only creates two new gaps that now have to be filled, would it?
I can not answer this question. I do not know what Darwin meant when he used the term and I have even less of a clue what Dembski meant. But this is a valid argument, without a clear definition of such terms how could we ever decide if we have identified a plausible transitional form?
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I'm sorry if the tone of this seems harsh, but I really think that definition is a step backwards for ID.
Not a problem, I’ve taken worse. Besides you raised some valid questions.
[ 10. April 2003, 09:08: Message edited by: Daniel Edington ]
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