Thursday, March 16, 2006

Round Two with Cordova

UPDATE: March 17. 2006.: Salvador has replied to this post. You will find his reply as comment seven here. I will let him have the last word.


Salvador has now replied to yesterday's post. You will find his reply as comment six.

Here's a quick recap of the argument thus far: On Tuesday evening I attended a talk given by John Angus Campbell on the subject of teaching ID in schools. During his talk Campbell argued that Darwin contrasted his ideas about common descent against rival ideas that we would nowadays refer to as ID. I criticized this on the grounds that there was an equivocation in the use of the term ID. The thing with which Darwin contrasted common descent was the idea that species were special creations of God and fixed through time. That is not what the term ID means today. Therefore, this was not a good argument for defending the inclusion of modern ID in science classes.

Salvador replied by providing a few quotes from Darwin in which Darwin explicitly refers to creation or design. This, sadly, completely missed the point. The question was whether what Darwin had in mind by those terms was equivalent to what modern ID folks have in mind. I went on to show, by placing Salvador's Darwin quotes in their proper context, that Darwin was not talking about ID as that term is understood today.

Apparently Salvador continues to miss the point. He writes:


Rosenhouse objects by saying that Darwin was arguing for common descent and the mutability of species as the conclusion of the theory. However, Rosenhouse misses the fact that Darwin had to use anti-Design arguments, particularly in chapter six to justify his conclusion. Also his writing was targeted at the pro-Design culture of the time. To arrive at that conclusion, Darwin had to make anti-Design arguments. One will see his writings anticipate design arguments of his day and today:

In Chapter 6


Organs of extreme perfection and complication.
….
It is scarcely possible to avoid comparing the eye to a telescope. We know that this instrument has been perfected by the long-continued efforts of the highest human intellects; and we naturally infer that the eye has been formed by a somewhat analogous process. But may not this inference be presumptuous? Have we any right to assume that the Creator works by intellectual powers like those of man?
….
may we not believe that a living optical instrument might thus be formed as superior to one of glass, as the works of the Creator are to those of man?

If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.


“It is scarcely possible to avoid comparing the eye to a telescope,” and in the modern day it is scarecly possible to avoid comparing the flagellum to an outboard motor, or some parts of the cellular machinery with a computer, or biological clock with clocks. Darwin recognized he had to address the design argument for his anti-creationist theory to be received.

Darwin would not reach Chapter 14 had he not felt he offered a sufficient designer substitute. I think Jason is underestimating the importance of the anti-design arguments which are in Darwin’s work. Darwin recognizes that the problem of design in “organs of extreme perfection” could sink his whole theory. And that is very much the same battle ground being fought today!


First off, in my original blog entry I was explicitly talking about Darwin's arguments in favor of common descent. Salvador's first reply used quotes related to that subject as well. He has now changed the subject to the question of how Darwin defended natural selection as the mechanism of evolution. This is a different issue.

Of more import, however, is that Salvador has once again misrepresented what Darwin said. Let's look at the full context of that “telescope” line:


He who will go thus far, if he find on finishing this treatise that large bodies of facts, otherwise inexplicable, can be explained by the theory of descent, ought not to hesitate to go further, and to admit that a structure even as perfect as the eye of an eagle might be formed by natural selection, although in this case he does not know any of the transitional grades. His reason ought to conquer his imagination; though I have felt the difficulty far too keenly to be surprised at any degree of hesitation in extending the principle of natural selection to such startling lengths.

It is scarcely possible to avoid comparing the eye to a telescope. We know that this instrument has been perfected by the long-continued efforts of the highest human intellects; and we naturally infer that the eye has been formed by a somewhat analogous process. But may not this inference be presumptuous? Have we any right to assume that the Creator works by intellectual powers like those of man? If we must compare the eye to an optical instrument, we ought in imagination to take a thick layer of transparent tissue, with a nerve sensitive to light beneath, and then suppose every part of this layer to be continually changing slowly in density, so as to separate into layers of different densities and thicknesses, placed at different distances from each other, and with the surfaces of each layer slowly changing in form. Further we must suppose that there is a power always intently watching each slight accidental alteration in the transparent layers; and carefully selecting each alteration which, under varied circumstances, may in any way, or in any degree, tend to produce a distincter image. We must suppose each new state of the instrument to be multiplied by the million; and each to be preserved till a better be produced, and then the old ones to be destroyed. In living bodies, variation will cause the slight alterations, generation will multiply them almost infinitely, and natural selection will pick out with unerring skill each improvement. Let this process go on for millions on millions of years; and during each year on millions of individuals of many kinds; and may we not believe that a living optical instrument might thus be formed as superior to one of glass, as the works of the Creator are to those of man? (Emphasis Added)


Note that first bold face statement, in which Darwin explicitly separates the question of common descent from the question of natural selection as the mechanism of that descent.

Now look at the final bold face statement. This makes it obvious that Darwin has no problem with the idea of intelligent design in the abstract. There is evidently nothing in his arguments that rules out the existence of a Creator who produces various works. It is, therefore, far too simplistic (to put it kindly) to say that Darwin was presenting anti-design arguments.

Now look at the middle bold face statement. What he is criticizing there is not the idea that there is a Creator who creates, but rather the presumption that such a Creator would produce his works by the same mechanisms through which human designers produce theirs. In other words, he is criticizing the idea that the eye (in this example) was produced by divine planning and fiat, as opposed to appearing via a gradual process presumably set in motion by the Creator.

Or to put it yet another way, he is not criticizing design in some vague sense, but rather the idea of the special creation of species with all of their structures in their present form. This is exactly what I argued in my previous post.

The only way Salvador's argument makes sense is if you construe the design argument as merely the claim that the complexity of certain anatomical structures, all by itself, implies they must have been designed. In that case, your argument is identical to the one offered by William Paley, and you should call it natural theology, not ID. Modern ID, as proposed by people like William Dembski and Michael Behe, was supposed to be a huge leap forward from Paley. They claimed to have produced a rigorous, quantifiable procedure for proving to a certainty that certain structures were designed. This was said to be an improvement over Paley's mostly analogical arguments.

The claim that Darwin set his arguments in opposition to ID can only be defended by defining ID in a way that ignores everything that modern ID proponents claim to have produced. But then you are left with the statement that Darwin set his arguments in opposition to Paley's earlier arguments, which everyone already knew.

So let's turn this in to something productive. If by “teaching ID” you mean that you should say that before Darwin it was very common for people to analogize complex anatomical structures to machines and conclude that they were designed directly by God, but then Darwin came along and showed that this analogy is seriously deficient, then I am all in favor of teaching ID. But if by “teaching ID” you mean that we should give respectful mention to things like irreducible complexity or complex specified information, then I am opposed to that, for the simple reason that we shoudn't be presenting false information to children.

Likewise, if “teaching the controversy” means that we should teach so much about evolution that we actually come to those esoteric issues that professionals actually argue about, then I am all in favor of it. But if by “teaching the controversy” you mean we should present respectfully the sort of bogus anti-evolution arguments offered by, say, Jonathan Wells, then I am against it.

Campbell himself was a bit confusing on these points. At times he seemed to be advocating the first option in these two paragraphs. Other times he seemed to prefer the second. Salvador appears to be defending the first in his reply. If that was his intention, then we don't disagree on very much, but he is abusing language in a serious way to describe that as teaching ID. But if actually he thinks that anything produced by contemporary ID advocates, most notably William Dembski and Michael Behe, is relevant to understanidng any of Darwin's arguments, then he is terribly confused.

2 Comments:

At 4:47 AM, Anonymous Richard Wein said...

Jason, I can't understand why you devote so much space to arguing with Cordova. Shooting fish in a barrel is no fun, especially when the fish keep on flapping after they're dead. ;-)

 
At 8:52 AM, Blogger Jason said...

richard-

Frankly, I find it hard to understand myself.

 

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