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Author
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Topic: Explanations by Design
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RBH
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Member # 380
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posted 22. August 2003 14:20
In the Flagellum thread a side-discussion started when Nelson-Alonso claimed that design theory "explains" the similarity between two biological systems. When I asked how design theory explained that similarity, he wrote quote:
A designer with one conceptual way of doing things (or designers with a common plan). No need for a couple of paragraphs.
That is, his explanation immediately appealed to a characteristic of the purported designer, namely that the designer designs consistently over instances, that it (or perhaps they) displays what I called "design themes" in the MDT thread.
Then when asked how one can know that the designer has that characteristic, Nelson-Alonso pointed right back to the biological systems, to "[t]he conceptual similarity" of the biological systems which was exactly the phenomenon to be explained. That is what I identify as a tightly circular explanation. Nelson-Alonso denies that it is circular.
Nelson-Alonso then claimed that an evolutionary explanation can be represented as being equally circular quote:
Darwinian evolution explains the similarity between two gene sequences because of common descent because it explains the similarity between two gene sequences which is the basis for common descent.
Here, though, Nelson-Alonso ignores the fact that there are multiple independent and semi-independent lines of evidence for the hypothesis of common descent: it does not depend solely on the phenomena it must explain. Most notably, that genetic transmission mechanisms are known that enable common descent to occur breaks the circularity that Nelson-Alonso attributes to the explanation in terms of common descent.
The design "explanation," though, has no such mechanisms, no independent lines of evidence, no way of escaping from its circularity that would allow it to be an "explanation" rather than merely a renaming of an unknown. It is locked into a tight self-referencing tautology: Things are the way they are because that's the way the designer did it, and we know that's the way the designer did it because that's the way things are.
This is a serious question: Is it even possible to provide a design "explanation" that does not appeal to a characteristic of the designer, as Nelson-Alonso's immediately and directly does, and that is something more than the bare assertion of 'common design'?
RBH
[ 22. August 2003, 14:41: Message edited by: RBH ]
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Nel
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posted 22. August 2003 14:31
RBH when you start a thread you should make sure that you accurately describe the contention you are replying to. You have several things wrong here.
RBH wrote:
quote:
That is, his explanation immediately appealed to a characteristic of the purported designer, namely that the designer designs consistently over instances, that it (or perhaps they) display what I called "design themes" in the MDT thread.
Your mistake here is that I did not initially point to a "characteristic" of the designer. I pointed to the fact that two distinct and unrelated systems use similar mechanisms, and that the similarity is largely conceptual. This phenonemon requires an explanation. The best explanation in my opinion is that of common design, a designer used the same "technique" to solve several problems. I then compared this to how we make similar inferences with designed systems that have conceptual similarities like LE and .NET.
RBH writes:
quote:
Nelson-Alonso then claimed that an evolutionary explanation can be represented as being equally circular
No, what I was pointing out was that the only way to make my logic circular is to repeat it multiple times in a single sentence. I can make anything look like circular logic doing that. The cat in the hat is named Pat because the Pat in the hat is a cat.
[ 22. August 2003, 14:33: Message edited by: Nelson-Alonso ]
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zygotecowboy
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Member # 220
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posted 22. August 2003 15:34
The notion of an "explanation" is an extraordinarily important one to the scientific enterprise. After all, the strength of a scientific hypothesis can be measured by its explanatory power.
That said, I think it's unfair to demand that IDists identify who or what did the designing of life. Though this particular issue is central to IDism (You can't have design without a designer), it's simply too difficult to address given the current state of knowledge.
However, explanations of ID aren't restricted to the identity of the designer(s). There are a number of other important questions that can be explored with IDism.
For instance, what exactly was designed? Is it just the information in DNA? Or were whole organisms assembled by the designer, as Paul Nelson apparently believes?
When did the designing occur? Did it precede the OOL here on Earth, consistent with Mike Gene's frontloading hypothesis? Were there multiple designing events throughout the history of life? Or did all the designing occur less than 10,000 years ago, as posited by Paul Nelson?
How was the designing accomplished? Can we even think of potential mechanisms that designers would use to design life?
These are all important questions that'll have significant impact on the intellectual development of IDism.
zc
[ 22. August 2003, 15:35: Message edited by: zygotecowboy ]
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Evan
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Member # 164
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posted 22. August 2003 21:13
ZC writes, “That said, I think it's unfair to demand that IDists identify who or what did the designing of life.”
As RBH and I have repeatedly argued, the identity of the designer(s) is not the issue: the issue is the nature of the designer - what characteristics of the designer can reasonably be inferred from whatever conclusions one draws (by whatever means) on the things that are designed.
I have not followed the previous thread, and am not interested in resurrecting its particular arguments here. But it does seem clear to me that it is a hollow argument to say that design is an “explanation” of something merely because there are similarities between two things, followed by the rationale that the reason we believe this is because, as RBH quotes Nelson, “A designer with one conceptual way of doing things (or designers with a common plan). No need for a couple of paragraphs.”
Even if we look at the analogy of human design (which is a very misleading analogy in certain ways), we see instances of designers following very similar plans, but we also see instances both of different designers using different plans and instances of the same designer using different plans at different times. Absent any other evidence, one could just as easily offer as an explanation for different things that they were designed by different designers, or perhaps a designer at different times.
Given that the only evidence offered in this explanation is one about how designers design, such an explanation can be offered for anything. Therefore, it is not useful, and is not really an explanation at all.
The circularity that RBH describes is a consequence of using in tandem the argument-from-design and the argument-to-design. Jonathan Wells succinctly summarizes these two arguments in his 1991 paper “Darwinism and the Argument to Design”
quote:
The Argument From Design
If human beings are designed, then God exists.
Human beings are designed.
Therefore, God exists.
The Argument To Design
If God exists, then human beings are designed.
God exists.
Therefore, human beings are designed.
With the understanding that we might be discussing unknown designer(s) who aren’t necessarily God, the general ID argument is the argument from design: given that design exists there must be a designer. But if the only evidence we can give for arguing that design exists is the argument that that is how a designer would design, then we have used the argument to design as the rationale for the argument from design.
This is clearly circular: First we say we know a designer exists because we see design, and then we say that we know design exists because we know that is how a designer would act. There is no independent evidence here - it is a tautological claim.
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Pim van Meurs
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Member # 541
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posted 22. August 2003 22:27
Nelson: Your mistake here is that I did not initially point to a "characteristic" of the designer. I pointed to the fact that two distinct and unrelated systems use similar mechanisms, and that the similarity is largely conceptual. This phenonemon requires an explanation. The best explanation in my opinion is that of common design, a designer used the same "technique" to solve several problems.
Sure, I could agree with this with the notion that a natural designer seems an obvious candidate. Of course this illustrates one of the major weaknesses in intelligent design arguments namely that once 'intelligent design' is identified (if so possible) the approach cannot eliminate "natural designers"
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Nel
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Member # 614
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posted 22. August 2003 23:09
Evan,
You ought to read the thread, I was not pointing to the "similarity of two things". I was pointing to the conceptual similarity of two very unrelated and different systems. When that occurs we infer common design, much like some people are now doing with LE and .NET.
Evan writes:
quote:
But if the only evidence we can give for arguing that design exists is the argument that that is how a designer would design,
There is nothing even remotely similar to this in ID. The evidence that design exists is the design itself. Of course if you hypothesize a certain type of designer (i.e. human-like with advanced intelligence), much like you would hypothesize a certain type of naturalistic mechanism, then you would predict to see certain things.
[ 22. August 2003, 23:21: Message edited by: Nelson-Alonso ]
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Argon
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posted 22. August 2003 23:26
RBH writes:
quote:
Here, though, Nelson-Alonso ignores the fact that there are multiple independent and semi-independent lines of evidence for the hypothesis of common descent: it does not depend solely on the phenomena it must explain. Most notably, that genetic transmission mechanisms are known that enable common descent to occur breaks the circularity that Nelson-Alonso attributes to the explanation in terms of common descent.
Spot on. Common descent is supported by morphological and historical evidence as well (independent lines of evidence). The relationships between sequence similarities and descent are evaluated against this data and against the backdrop of known and testable genetic mechanisms, it's hard to claim that sequence-based phylogenies are based on circular reasoning.
[ 22. August 2003, 23:27: Message edited by: Argon ]
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Evan
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posted 22. August 2003 23:47
Nelson writes,
quote:
Evan, You ought to read the thread, I was not pointing to the "similarity of two things". I was pointing to the conceptual similarity of two very unrelated and different systems. When that occurs we infer common design, ...
I just simplified the statement. I could have written “But it does seem clear to me that it is a hollow argument to say that design is an “explanation” of something merely because there are conceptual similarit[ies between] two very unrelated and different systems,” and my point would be the same.
Nelson, I would be interested in your response to the next part of my argument: that we also know that different designers of the same designer at different times use different plans. Therefore can we conclude also that things that are different are designed because that is a quality of there being different designers? Is this a valid, analogous, argument to your argument about design being an explanation for “conceptual similarit[ies between] two very unrelated and different systems.”?
Then in response to my statement that “But if the only evidence we can give for arguing that design exists is the argument that that is how a designer would design, ...”
Nelson responds,
quote:
There is nothing even remotely similar to this in ID. The evidence that design exists is the design itself. Of course if you hypothesize a certain type of designer (i.e. human-like with advanced intelligence), much like you would hypothesize a certain type of naturalistic mechanism, then you would predict to see certain things.
This is certainly circular reasoning - “The evidence that design exists is the design itself.” But how do we know that something is designed? In this particular case, it appears your argument is the evidence that something is designed is that one class of known designers uses at times similar plans in disparate situations. But my point is that in other situations, known designers use very different plans in disparate situations - therefore different features in different situations would equally be evidence for design according to this reasoning.
RBH’s point is that if you base your argument on the hypothesis that the designer(s) would use similar plans in different situations, but the only evidence you have for such a hypothesis is that in fact we see similar plans in different situations, then you have engaged in circular reasoning. Your hypothesis about the nature of the designer contains within it the very fact that you ostensibly are trying to use as a conclusion: that the existence of similar plans is evidence for designers because that is a quality that you hypothesize is true of designers. But the only evidence that you have for this speculation about the nature of the designers is the very fact that you wish to establish by invoking the designer. And so it goes, round and round...
There has to be some independent evidence for design. I’m not saying there isn’t such evidence, but I am saying that this particular argument is not evidence based, and establishes nothing.
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Argon
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posted 23. August 2003 00:52
Evan writes:
quote:
There has to be some independent evidence for design. I’m not saying there isn’t such evidence, but I am saying that this particular argument is not evidence based, and establishes nothing.
Indeed. After all, this is what William Dembski is trying to do with his CSI and filter concepts and what Michael Behe wrote DBB about.
Perhaps a way out for Nelson-Alonso would be to suggest that biological systems appear designed because that's how we'd design them. Now that may be doubtful -- as suggested by others in this topic -- but the analogy could work at least in principle. For example: if we knew that species were routinely created as products of design one might make a case by analogy.
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nobody
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posted 23. August 2003 13:00
quote:
Perhaps a way out for Nelson-Alonso would be to suggest that biological systems appear designed because that's how we'd design them.
No. A "way out", as you put it, is not needed. Humans are not capable of designing biological systems. We can only play around with God's superior designs and then wait to see what happens, sometimes with disastrous results.
Unless you want to count something like an artificial heart as a "system".
http://news.bbc.co.uk/2/hi/health/1420737.stm
If you do count the mechanical heart as a system you will still notice that God's heart design works much better and lasts longer, even though much human genius went into the design of the mechanical unit.
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Evan
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posted 23. August 2003 13:53
However, especially for the sake of the topic here, which has to do with a particular argument that relates the design to the designer, we don't know that God, or any other intelligent agency, designed the heart or anything else.
The question on the table is the evidence for design, and that claim being made by me (and RBH also, I think) is that beliefs about the nature of the designer(s) - their capabilities as opposed to the identity(ies), cannot be used as evidence for design, because we have no independent evidence for said designers other than the purported design itself.
[ 23. August 2003, 15:50: Message edited by: Evan ]
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Pim van Meurs
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posted 23. August 2003 15:24
I would like to extend the argument namely that even if intelligent design could be (accurately) infered, this says nothing about the intelligent designer. Wesley Elsberry raised this issue in his review of Dembski's works.
quote:
Dembski has either shown in the above that natural selection is intelligent, or that there is no conceivable test that will distinguish the action of natural selection from the action of an intelligent agent. That is, the process of natural selection fits the triad listed. Actualization - heritable variation arises. Exclusion - some heritable variations lead to differential reproductive success, so that some heritable variation increases in representation and other heritable variation decreases in representation in the population.
Specification - environmental conditions specify which variations are preferred, and thus yields directed contingency.
Link
We do not seem to have independent evidence of the intelligent designers in nature, other than of course the natural processes which seem to be included in the term "intelligent designer".
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Argon
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posted 23. August 2003 17:04
nobody writes:
quote:
No. A "way out", as you put it, is not needed. Humans are not capable of designing biological systems. We can only play around with God's superior designs and then wait to see what happens, sometimes with disastrous results.
A way out is indeed needed. If, as you say, humans are incapable of designing biological systems, and you cannot demonstrate the existence of any other beings in this part of the galaxy that are capable, then there is no way to use analogies.
Besides, the question is not whether humans are capable at designing biological systems, but how they would appear if we could. Remember that TRIZ stuff? (link). Personally, I'd expect to see a lot more stuff that looked like horizontal transfer...
[ 23. August 2003, 17:04: Message edited by: Argon ]
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Nel
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posted 23. August 2003 17:12
Argon writes:
quote:
Common descent is supported by morphological and historical evidence as well (independent lines of evidence). The relationships between sequence similarities and descent are evaluated against this data and against the backdrop of known and testable genetic mechanisms, it's hard to claim that sequence-based phylogenies are based on circular reasoning.
As I said in my second post, I was not really claiming that the inference to common descent uses circular logic. Merely that one can easily make any argument sound circular.
However, in a way, homology is a circular argument. One needs to assume that the similarity is due to common descent, and then say that homology is evidence for common descent. One can merely say that the similarity is a coincidence or due to common design.
On the other hand, there are a lot of morphological traits that do unite large groups of animals because they were invented once. For example, placenta. But the tricky part of morphology-based phylogenies are those examples of convergence. Molecular phylogenies also encounter problems with deep branches or recent clusters of species. I also happen to go along with the hypothesis that the origin of life started with a consortium of cells rather then one very simple universal ancestor.
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Pim van Meurs
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posted 23. August 2003 17:31
Nelson:
However, in a way, homology is a circular argument.
I assume though that like with common descent you are not really arguing that homology IS circular, merely that it can be portrayed as such. In fact Wells tried to make such a claim somewhat unsuccesfully
From NCSEWeb
quote:
Wells claims that homology is used in a circular fashion by biologists because textbooks define homology as similarity inherited from a common ancestor, and then state that homology is evidence for common ancestry. Wells is correct: this simplified reading of homology is indeed circular. But Wells oversimplifies a complex system into absurdity instead of trying to explain it properly. Wells, like a few biologists and many textbooks, makes the classic error of confusing the definition of homology with the diagnosis of a homologous structure, the biological basis of homology with a procedure for discovering homology. In his discussion, he confuses not only the nature of the concept but also its history; the result is a discussion that would confuse. What is truly important here is not whether textbooks describe homology circularly, but whether homology is used circularly in biology. When homology is properly understood and applied, it is not circular at all.
And while a simplistic interpretation of homology may indeed run the risk of 'tautology' it is important to realize how homology is used and applied in biology.
quote:
This criticism relies on a faulty view of what scientific definition amounts to. A scientific definition is not a semantic stipulation that creates an analytically true statement (i.e. a statement the denial of which is self-contradictory). Rather, a scientific definition typically states a property that is considered to be the most deeply explanatory of the phenomena that are central to the term being defined. Lankester and Mayr consider ancestry to explain patterns of homology, and stress that fact by making it the definition. The historical definition is not viciously circular as long as homologies can be recognized and picked out by criteria other than common ancestry. It is an empirical fact that homologies (as picked out by the criteria below) are arranged among organisms in a pattern that is explainable by common ancestry, and independent evidence from various fields supports common ancestry as a historical fact.
[ 23. August 2003, 17:38: Message edited by: Pim van Meurs ]
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