Reflectorites
On Sun, 10 Sep 2000 15:18:27 -0500, Chris Cogan wrote:
[continued]
CC>In fact, if we did not know
>better from empirical observation, and if we thought life was designed,
>we'd guess that life would be much different from what it turns out to be,
>because we'd guess that the designers would be intelligent enough, good
>enough biological engineers, not to design a kludge like the human wrist
Even if we granted (for the sake of argument) that the human wrist was a
"kludge" the fact is that even a "kludge" is designed:
"kludge... a system and especially a computer system made up of
poorly matched components"
(http://m-w.com/cgi-bin/dictionary?book=Dictionary&va=kludge)
BTW I would like to see Chris' *evidence* why he thinks "the human
wrist" is a "kludge". I must admit I have never heard of that argument in
the evolutionary literature. Did Chris read it somewhere (and if so where?)
or did he just make it up?
CC>or
>the nerve pathways from the retinal cells in the human eye (the nerves go
>*in front* of the light-sensitive rods and cones, thus blocking some of the
>light).
Chris does not even demonstrate that "blocking some of the light" is a
problem for vision. It isn't because the whole visual *system* of two eyes
and the brain's visual processing sub-system amply compensate for any
minor loss of light this might cause (which AFAIK has never even been
quantified).
Nevertheless, this has been one of the classic Darwinist arguments against
design, as Denton explains:
"In all non-vertebrate eyes, and in the pineal or dorsal eyes of primitive
vertebrates, the photoreceptors point toward the light. However, in the
vertebrate lateral eye, the photoreceptors point backwards away from the
light towards the retinal epithelium and the choroidal blood sinuses. This
arrangement necessitates the placement of the neural cell layer--which
relays the visual image from the retina to the brain--between the
photoreceptors and the light, and results in the blind spot where the axons
of these neural cells leave the retina for the brain via the optic nerve.
Generations of Darwinists have seized on this apparently illogical
arrangement and particularly the consequent "blind spot" as a case of
maladaptation. The following comments by Dawkins are typical:
"Any engineer would naturally assume that the photocells would point
towards the light, with their wires leading backwards towards the brain. He
would laugh at any suggestion that the photocells might point away from
the light, with their wires departing on the side nearest the light. Yet this is
exactly what happens in all vertebrate eyes. Each photocell is, in effect,
wired in backwards, with its wires sticking out on the side nearest to the
light. This means that the light, instead of being granted an unrestricted
passage to the photocells, has to pass through a forest of connecting
wires, presumably suffering at least some attenuation and distortion
(actually probably not much but, still, it is the principle of the thing that
would offend any tidy-minded engineer!) (Dawkins R., "The Blind
Watchmaker," 1986, pp.93-94,
(Denton M.J., "The Inverted Retina: Maladaptation or Pre-adaptation?" Origins &
Design, Vol. 19, No. 2, Access Research Network, 1999.
http://www.arn.org/docs/odesign/od192/ir192summ.htm).
Ayoub in 1996 had looked at this (again no pun intended!) from the angles
of 1. Regenerating photoreceptive pigments; 2. Recycling of
photoreceptive material; and 3. Absorption of excess light; and then
conducted a thought experiment with the photorectors and retina reversed:
"So, as a thought experiment, let's fix the blind spot. We will start
by turning the photoreceptors around, so their wiring isn't in the
way. We have eliminated the blind spot, providing slightly better
sight in one portion of the eye. Now, however, the blood vessels
and RPE, needed to maintain the photoreceptors, must be located
on the inner side of the retina, between it and the lens. This places a
large capillary bed (containing many red blood cells) and an
epithelial tissue in the path of the light, significantly degrading the
visual information passing to the photoreceptors. Furthermore,
since the photoreceptors continually shed material from their outer
segments, dumping this opaque waste in the path of the light would
greatly diminish the amount of light reaching the photoreceptors.
Our proposed change also reduces the quality of the light, by
refracting it with the opaque pieces of shed outer segment
membrane. We might imagine simply placing the RPE at the back
of the retina, but this raises the problem of how to dispose of spent
outer segment membranes, so that the photoreceptors can be
quickly regenerated. Or, perhaps, we could surround each
photoreceptor cell by RPE cells, but this would need increase the
space between the photoreceptors, thus decreasing the resolution of
vision. These design changes may force temporal or spatial
decrements in vision. Are these improvements? Hardly; indeed, our
thought experiment has taken the vertebrate eye rapidly downhill.
In trying to eliminate the blind spot, we have generated a host of
new and more severe functional problems to solve. Our "repair"
seems far worse than the apparent flaw we wanted to fix." (Ayoub
G., "On the Design of the Vertebrate Retina," Access Research
Network, Origins & Design, Vol. 17, No. 1, 1996.
http://www.arn.org/docs/odesign/od171/retina171.htm)
The above would be sufficient to establish that the vertebrate eye is not
badly designed and may in fact be *well*-designed.
But then in 1999 Denton considered the fact that land-dwelling vertebrate
vision requires a lot of oxygen:
"The remarkable capacity of the unique choriocapillaris system to
deliver copious quantities of oxygen to the photoreceptors has an
important consequence--it obligates the necessity for a capillary
network within the photoreceptor layer and this in turn allows the
photoreceptor cells to be packed tightly together, thus maximizing
the resolving power of the eye. It is also hard to imagine how a
standard-type capillary network to carry the necessary quantities of
blood directly through the photoreceptor cell layer could be
arranged without causing at least some decrease in the packing
density of the photoreceptors and a consequent decrease in the
resolving power of the eye. (Interestingly, in all known high-acuity
eyes, including the compound eyes of insects and other arthropods
and the camera-type eyes of various groups, including the
cephalopod and photoreceptors, are packed tightly together and not
separated by either blood vessels or any other type of intervening
tissues or structures.)" (Denton, 1999).
So therefore it seems that the vertebrate retina is *better* placed where it
is behind the photoreceptors:
"Taken together, the evidence strongly supports the notion that the
inverted retina and its major consequence (the positioning of the
photoreceptors in the outer section of the retina where they are in
intimate contact with the choriocapillaris) is a specific adaptation
designed to deliver abundant quantities of oxygen to the
photoreceptor cells commensurate with their high energy demands-
-especially in metabolically active groups such as the birds and
mammals. Rather than being a case of maladaptation, the inverted
retina is probably an essential element in the overall design of the
vertebrate visual system. This conclusion is reinforced by the
difficulty of envisaging alternative means of delivering the required
amounts of oxygen to the photoreceptor cell layer if the retina had
the typical non-inverted design of the sort that might appeal to a
"tidy-minded engineer." (Denton, 1999).
One mark of a good theory is when one of its claimed major weaknesses
turns out to be one of its major strengths. In the case of the vertebrate eye,
far from being badly designed, it turns out the counter-intuitive placement
of the photoreceptors in front of the retina is an example of *good* (I
would say *brilliant* but I'm biased! :-)) design!
But (as the TV commercial says) there's more (i.e. it gets worse for the
Darwinists). Since this design decision was made before the vertebrate-
invertebrate split about1 billion years ago:
"I wouldn't be surprised if the common ancestor of all surviving
animals, who lived perhaps a billion years ago, possessed eyes."
(Dawkins R., "Climbing Mount Improbable," 1996, p.128)
it actually is a good example of far-sighted (again pun unintended!) design
for vision on land which would not be needed until about 600 million years
later:
"Finally, there is the fascinating question of pre-adaptation.
Although all vertebrates have the same inverted design the
interesting question arises as to whether the inverted design is a
necessity for high-resolution vision in the cold-blooded vertebrates
such as fish which have lower metabolic rates than the warm-
blooded vertebrates such as mammals and birds. In this context the
high resolution eye of the cephalopods, including the octopus and
squid, is instructive. The cephalopods have a typical non-inverted
retina which is comparable in resolving power to the eyes of many
vertebrates, have metabolic rates similar to that of fish and other
cold- blooded vertebrates (even though the maximum oxygen
capacity of cephalopod blood is only one third that of a fish), and
inhabit an aquatic environment similar to that of many fish. This
implies strongly that high- acuity vision in the eyes of cold-blooded
vertebrates would be possible with a non-inverted retina and that it
is only in the case of the higher and warm-blooded vertebrate
species where the metabolic rates are far higher that the inverted
arrangement to bring the photoreceptors adjacent to the choroidal
vessels is a necessity for phototransduction. In other words, the
inverted retinal design is almost certainly not an adaptive necessity
in cold-blooded vertebrates." (Denton, 1999).
CC>Things like the wrist *do* have evolutionary explanations,
It depends on what Chris means by "evolutionary explanations". If he
means that random mutation and natural selection can provide a plausible,
complete, and testable explanation of the origin of the human wrist, I
would be interested to see it.
But of couse even if Chris could provide a plausible, complete and testable
Darwinian "evolutionary explanation" of the origin of the human wrist, that
fitted all the known facts, he would have to face the fact that more than
one theory can be supported from the same facts:
"Scientists whose theories make seemingly improbable events very
probable, and who then, when these events are observed,
congratulate themselves on being right, are often dismayed to find
that other theories predict the same events and have the advantage
of actually being right. (Yet remember that it is possible for
evidence to support a theory despite also giving support to a
competing theory....)" (Leslie J., "Universes," Routledge: London,
1996, p.155)
What Chris would need to show is that *only* an "evolutionary
explanation" would fit all the facts.
CC>but no
>design explanations, unless you count "Well, that's just the way the
>designers chose to do it;
Not really. A good "design explanation" could be made of the human wrist
conforming to the same basic vertebrate limb plan on the principle of
variation on a theme:
"Notice, this is exactly what we would expect as evidence of good
creative design and engineering practice. Suppose you were in the
bridge-building business, and you were interviewing a couple of
engineers to determine whom you wanted to hire. One fellow says,
"Each bridge I build will be entirely different from all others."
Proudly he tells you "Each bridge will be made using different
materials and different processes so that no one will ever be able to
see any similarity between the bridges I build. " How does that
sound? Now the next fellow comes in and says, "Well, out back in
your yard I saw a supply of I-beams and various sizes of heavy
bolts and cables. We can use those to span either a river or the San
Francisco Bay. I can adapt the same parts and processes to meet a
wide variety of needs. You'll be able to see a theme and a variation
in my bridge building and others can see the stamp of authorship in
our work." Which fellow would you hire?" (Parker G.E., "Creation:
the Facts of Life", 1980, p.26)
And what is Chris' "evolutionary explanation"? Is it "Well, that's just the
way the" `blind watchmaker' "chose to do it"?
CC>who are we to question why the designers did
>things the way they did?"
Chris is getting confused between `why' "explanations" and `that'
"explanations".
We don't need to know "why" even human designers designs things in
order to know *that* they are designed:
"Moreover, the specifics of design-purpose, plan, intent, function-
may be unrecognized even when designedness is evident. The
Smithsonian Institution has a collection of obviously designed
human artifacts, concerning the purposes of which no one has a
clue. In any case designedness and artifactuality, although they are
closely linked, are not coextensive, and recognition of designedness
s typically subordinate to, even dependent upon, recognition of
rtifactuality." (Ratzsch D., in Dembski W.A., ed., "Mere Creation,"
998, p.294)
If SETI receives a message from aliens SETI would not have to explain
"why" the aliens sent the message to know that it is designed.
In the case of the vertebrate eye having its photoreceptors `wired
backwards' we can in fact provide a good "why" explanation. But in other
cases it might be more difficult.
CC>This last, of course, is not an explanation *at all*.
>>It's the *evasion* of explanation.
Who said it was an "explanation"? Unless Chris can provide details where a
leading design theorist provided such an explanation it is just a straw man,
set up to be knocked down.
CC>It's the assertion that what we
>*do* know (that other organisms have properly-built eyes, for example)
See above. The invertebrate eye is "properly-built" built for a marine
invertebrate existence where high-resolution, long distance vision is not
necessary, by having the photoreceptors behind the retina.
But the *vertebrate* eye is also "properly-built" built for a *land*
vertebrate existence where high-resolution, long distance vision *is*
necessary, by having the photoreceptors in front of the retina so the latter
has accesss to a strong blood supply without *really* obscuring vision.
CC>should be *set aside* in deference to the mindless "Well, that's just the
>way they did it" excuse.
See above. It turns out that it is the *anti-designist* objection which is the
"mindless" one. I bet the anti-designists like Chris just just keep on
believing it anyway, despite the new evidence that the vertebrate eye is very
well designed.
CC>It is a demand on the part of ID theorists that we
>ignore the *facts* of biological reality
In fact it is the "ID theorists" who are pointing out to anti-designists what
*are* "the *facts* of biological reality" and it is the *anti-designists* who
are doing the ignoring!
CC>in favor of a belief in designers
>whose minds are not known
See above. It is not necessary that the "designers ...minds are... known". It
is enough to know that there *is* evidence of design.
But of course the *Christian* design theorists do not claim that the
Designer's mind is not known, since they claim He has communicated a
great deal of what is in His mind to man.
CC>and who, judging from their work, are *idiots*
So Chris believes that he (including his mind and reasoning) was designed
by "idiots"?
I extend him my sympathy. I believe that I (including my mind and
reasoning) was designed by *very* Intelligent Designer"!
Chris has the same self-referential problem that Darwin had. If his theory
was true, there would be no reason to believe that his theory was true:
"Charles Darwin himself once said, "The horrid doubt always arises
whether the convictions of man's mind, which has developed from
the mind of the lower animals, are of any value or at all
trustworthy. Would anyone trust the conviction of a monkey's
mind, if there are any convictions in such a mind?" In other words,
if my brain is no more than that of a superior monkey, I cannot even
be sure that my own theory of my origin is to be trusted. Here is a
curious case: If Darwin's naturalism is true, there is no way of even
establishing its credibility let alone proving it. Confidence in logic is
ruled out- Darwin's own theory of human origins must therefore be
accepted by an act of faith. One must hold that a brain, a device
that came to be through natural selection and chance-sponsored
mutations, can actually know a proposition or set of propositions to
be true." (Sire J.W., "The Universe Next Door," 1988, p94)
CC>Naturalistic evolution gives us a means of *understanding* why these crazy
>facts *are* facts, because it gives us a means of showing how they arose
>out of the accidents of history.
Not really. "Naturalistic evolution" just *assumes* up front that
these "facts" are "accidents of history" and then proceeds to
interpret the "facts" consistent with that original assumption.
In any event, since Chris thinks his mind has been designed by "idiots" then
he would not know that his "understanding" of the facts was reliable.
After all, no one would trust the output of a computer that was produced
by designers "who judging from their work, are *idiots*"
CC>These and many other facts make *sense* naturalistically,
See above. By Chris' own admission his "sense" has been produced by
"idiots". So on that basis his perception of what "make *sense*
naturalistically" is likely to be unreliable.
But in any event, "the facts" of the vertebrate eye *don't* "make sense
naturalistically". Naturalistic `blind watchmaker' evolution could not
explain why what they regard as an inferior type eye arose in the first place
and then persisted for 600 million years in a marine environnment in which,
by their own admission it had a disadvantage, until it became advantageous
about 400 million years ago when vertebrates came onto the land.
But from my `far-sighted Intelligent Designer' perspective I can offer an
explanation why 1 billion years ago the vertebrate and invertebrate eye
diverged, when it had no immediate advantage, and then about 400 million
years ago when vertebrates came onto the land the advantage of front
photoreceptors became apparent.
Now I would like to see Chris' explanation that "makes *sense*
naturalistically", of why this grand-daddy of all pre-adaptations occurred 1
billion years ago when by his own claim it is supposed to be a bad design?
CC>but they *don't* make sense in *intelligent* design terms.
How would Chris *know* that "they *don't* make sense in *intelligent*
design terms" when he is obviously so highly prejudiced against ID that he
could not understand it if he wanted to (which he doesn't)!
But I have provided above explanations that "make sense in *intelligent*
design terms". Now it is Chris' turn to show how they "make sense in"
naturalistic evolution "terms", i.e. the "work" of "*idiots*".
CC>That's why ID theorists do *not* have an ID *explanation* for these
>facts.
I wonder which "ID theorists" Chris asked? The eye explanations have
been on the main "ID theorists" web site since mid-1996 and early 1999.
CC>That's why they are forced to hem and haw and claim, totally without
>evidence, that their designer must have reasons of which we do not know.
See above. There is no requirement to know the designer's "reasons" to
know that something has been designed. However in some cases the
designers reasons can be inferred.
CC>They are, in effect, using the *failure* of their theory to "justify" a
>bizarre *extension* of it.
The "theory" would only be a "failure" if it in fact was what Design
theorists claimed. But AFAIK no Design theorist has ever claimed to know
in detail the designer's "reasons".
CC>Now the designers are intelligent, but *we* have
>no means of understanding their intelligence.
Chris is *really* getting confused. First, he claims he can judge from the
designer(s) "work" that they "are *idiots*" which must mean he claims he
can have *some* understanding" of "their intelligence"
Second he confuses not knowing the the designer's "reasons" with not not
having some "understanding" of "their intelligence".
If SETI received a signal in a high-level mathematical code, as in the movie
"Contact" we would know that the minimum level of "intelligence" of the
sender was high, but we might not know much about their "reasons" for
sending the message.
From my `far-sighted Intelligent Designer' perspective I could infer from
the evidence of the vertebrate eye being prepare 600 million years in
advance that the Designer's intelligence is very great indeed!
CC>On what grounds then, can they be said to *be* intelligent?
See above. Chris original premises are faulty and therefore so is his
conclusion.
CC>In short, ID theory demands that we are to subvert our ability to
>understand physical reality and even to think logically in favor of a
>nearly mindless acceptance of a belief in a gang of unknown idiots
See above.
CC>This epistemological subservience to blind faith is the real horror. "Junk
>your knowledge of physics, chemistry, geology, and genetics!
I sometimes wonder who Chris is *really* attacking. No Design theorist
that I am aware of advocates `blind faith'. In fact the only advocates of
`blind faith' that I know of are two Christian evolutionists Cliff Hamrick
and Pim van Meurs (alias FMAJ1019).
If Chris so dislikes "blind faith" why didn't he take it up with Cliff at the
time and why doesn't he take it up with Pim/FJ now?
I certainly do not regard my "faith" as "blind"!
CC>Throw out your knowledge of the history of life on Earth!
Another straw man. In fact it is "knowledge of the history of life on Earth"
that is providing more evidence for Design and more problems for
Naturalistic Evolution!
CC>Ignore the many facts of life
>that make sense in naturalistic terms but yield nothing but excuses and
>emptiness in intelligent design terms.
See above explanations "in intelligent design terms" about the vertebrate
eye. I wonder what "excuses and emptiness" Chris will offer in reply?
CC>Don't think, *believe!* Don't question the human wrist,
I still am not clear what Chris thinks the problem with "the human wrist". It
seems to me to have a remarkably versatile design.
CC>take it on faith that the designers knew what
>they were doing;
There is nothing strange in that. We usually assume that "designers knew
what they were doing" even if we don't always understand why they did it.
CC>it doesn't work well, but who are *we* to question the
>wisdom of the great and wonderful designers?" Etc., etc., etc.
Chris's first task is to establish that "it *doesn't* work well".
The human wrist and the vertebrate eye in fact do at least "work well".
What does Chris want a corksrew for opening wine bottles for one and
screw-in telescope attachments for the other?
CC>(Sorry. Sometimes I get carried away by the endlessness of the evasions and
>nonsense and anti-science coming from the ID camp.)
I sometimes wonder who exactly Chris has these discussions with in the
"ID camp". It sounds to me like he also has an `imaginary friend' who puts
up nice and easy straw man ID answers so that Chris can feel good
knocking them down!
I have answered Chris' questions point-by-point, spread over four
messages. Now let's see who is indulging in "evasions", "nonsense" and
"anti-science"!
Steve
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Stephen E. (Steve) Jones ,--_|\ Email: sejones@iinet.net.au
3 Hawker Avenue / Oz \ Web: http://www.iinet.net.au/~sejones
Warwick 6024 -> *_,--\_/ Phone: +61 8 9448 7439
Perth, Western Australia v "Test everything." (1 Thess. 5:21)
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