DNAunion: Here are some other references I found to Dawkin's model and how it works. Note that the first representation, though contained in Behe's book, is not made by an IDist (it is made by E. Sober). Here is material from another of my posts from another site:
DNAunion: In keeping with one of my earlier statements, here are portions of Behe’s refutation of an analogous analogy given by Richard Dawkins that supposedly demonstrates the power of cumulative selection in natural evolution:
“”The fact that mutation-selection has two parts … is brought out vividly by Richard Dawkins in his book
The Blind Watchmaker. Imagine a device that is something like a combination lock. It is composed of a
series of disks placed side by side. On the edge of each disk, the twenty-six letters of the alphabet appear. The disks can be spun separately so that different sequences of letters may appear in the viewing window.
How many different combinations of letters may appear in the window? There are 26 possibilities on each
disk and 19 disks in all. So there are 26^19 different possible sequences. One of these is METHINKSITISLIKEAWEASEL. … The probability that METHINKSITISLIKEAWEASEL will appear after all the disks are spun is 1/26^19, which is a very small number indeed. …
But now imagine that a disk is frozen if it happens to put a letter in the viewing window that matches the
one in the target message. The remaining disks that do not match the target then are spun at random, and
the process is repeated. What is the chance now that the disks will display the message METHINKSITISLIKEAWEASEL after, say, fifty repetitions?
The answer is that the message can be expected to appear after a surprisingly small number of generations
of the process. …
Variation is generated at random, but selection among variants is non-random”. [Sober, E. (1993) Philosophy of Biology, Westview Press, Boulder, Co, p. 37-38]
This analogy is intended to illuminate how complex biological systems might have been produced. So we
are asked to conclude, based on the spinning-disk analogy, that the cilium evolved step-by-step, that the
initial steps in vision could be produced gradually, and so forth. The analogy is offered in lieu of actual
evidence that these or other complex systems could have evolved in a Darwinian fashion. And Sober
thinks the analogy is so compelling that, based on it, Dawinian evolution now wins as the inference to the
best explanation. Dawkins’ analogy (which is slightly different in details in his book versus Sober’s
rendition), though transparently false, appears to have captured the imagination of some philosophers of
biology. Besides Sober, Michael Ruse has used a similar example in his book Darwinism Defended, as has
Daniel Dennett in Darwin’s Dangerous Idea.
What is wrong with the Dawkins-Sober analogy. Only everything. It purports to be an analogy for natural
selection, which requires a function to select. But what function is there in a lock combination that is
wrong? Suppose that after spinning the disks for a while, we had half of the letter right, something like
MDTUIFKQINIOAFERSCL (every other letter is correct). The analogy asserts that this is an improvement over a random string of letters, and that it would somehow help us open the combination lock. But if your life depended on opening a lock that had the combination METHINKSITISLIKEAWEASEL, and you tried
MDTUIFKQINIOAFERSCL, you would be pushing up daisies. If your reproductive success depended on opening the lock, you would leave no offspring. Ironically for Sober and Dawkins, a lock combination is a highly specified, irreducibly complex system that beautifully illustrates why, for such systems, function cannot be approached gradually.
Evolution, we are told by proponents of the theory, is not goal directed. But then, if we start from a random
string of letters, why do we end up with METHINKSITISLIKEAWEASEL instead of MYDARLINGCLEMENTINE or MEBETARZANYOUBEJANE? As a disk turns, who is deciding which letters to freeze and why? Instead of an analogy for natural selection acting on random mutation, the Dawkins-Sober scenario is actually an example of the very opposite: an intelligent agent directing the construction of an irreducibly complex system. The agent (Sober here) has the target phrase (lock combination) in mind and guides the result in that direction as surely as a fortune-teller guides a Ouija board. This hardly seems like a secure foundation upon which to build a philosophy of biology.
The fatal problems with the analogy are not difficult to see. It was amusingly skewered by Robert Shapiro, a professor of chemistry at New York university, in his book Origins: A Skeptic’s Guide to the Origin of Life, which was published seven years before Sober’s Book.” (Michael Behe, Darwin’s Black Box: The Biochemical Challenge to Evolution, Free Press, 1996, p220 – 221)
DNAunion: Here is another quote on the same analogy by Dawkins – this one is from a Panspermia web site:
”Richard Dawkins has written several computer programs which function, he says, like evolution. Computers today are powerful and can run the programs very quickly. This speed enables Dawkins to compress a single generation, or computer trial, into a fraction of a second. In his widely acclaimed 1987 book The Blind Watchmaker … he tells about several such programs. …
One of Dawkins' programs begins with a random string of letters and creates a sentence. The sentence is
from Shakespeare, "METHINKS IT IS LIKE A WEASEL." The evolution takes only 64, 43, or 41 generations in different computer trials. Dawkins acknowledges that the chance of that short sentence getting produced in a given random trial is, "about 1 in 10,000 million million million million million million." But, he continues, with "cumulative selection," the thing becomes doable. Each time a random computer trial happens to produce a correct letter in a slot, that letter is preserved by cumulative selection (p 46-50).
There is a problem with using Dawkins's scheme as an analogy for evolution. In order for there to be such a
thing as a correct letter, the complete sentence has to already exist. In real life, this would require evolution to be teleological, that is, to have a prescribed goal. Teleology in nature is the very thing neo-Darwinists abhor. Random mutations cannot have any prescribed goal. For life to evolve this way, what preexisting model is it emulating?
Alternatively, if there is no model in Dawkins's computer, how is the sentence that is only 61 percent
wrong, favored over the one that is 86 percent wrong? How is "MDLDMNLS ITJISWHRZREZ MECS P," better than "WDLTMNLT DTJBSWIRZREZLMQCO P?" After presenting this idea, Dawkins then admits, "Life is not like that" (p 50).” (http://www.panspermia.org/computrs.htm)
DNAunion: Here is another quote, from the book Mere Creation, that exposes the logical flaw in Dawkins’ analogy.
”As Dawkins points out (Dawkins 1987, 46-47), the time required to reasonably expect a monkey to type
even one line from Shakespeare – say, “Mehinks it is like a weasel” from Hamlet – would be astronomical.
To get any significant level of order by random assembly of gibberish is out of the question in a universe merely billions of years old and a similar number of light-years across.
But Dawkins (who, after all, believes our universe was devoid of mind until mind evolved) claims that
selection can vastly shorten the time necessary to produce such order. He programs his computer to start
with a line of gibberish the same length as the target sentence and shows how the target may be reached by
selection in a very short time.
Dawkins accomplishes this (Dawkins 1987, 46-50) by having the computer make a random change in the
original gibberish and test it against the target sequence, selecting the closer approximation at each step and then starting the next step with the selected line. For instance, starting with the line
WDLTMNLT DTJBSWIRZREZLMQCO P Dawkin’s computer reaches its target in just 43 steps or generations. In two other runs starting with different gibberish, the same target is reached in 64 and 41 generations.
This seems impressive. Yet it does not tell us much about natural selection (i.e., selection as it occurs in nature as opposed to in a computational environment). A minor problem with Dawkin’s program is that he designed it to converge far more rapidly than real mutation and natural selection. [discussion of Newman’s own improved program omitted]…
But a far more serious problem with Dawkin’s simulation is that real mutation and selection do not have a
template to aim at unless we live in a designed universe (see Ludwig 1993, 256-259). …” (Robert C.
Newman, Artificial Life and Cellular Automata, chapter 18 of Mere Creation, InterVarsity Press, 1998,
436-437)
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