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The
Atheist Devotional: Timeless Meditations for
the Godless by M. Moore
Copyright ă 2008 M. Previous: Reading Number 10: Bertrand Russell’s Mind Speaks Up Next: Reading Number 12: Dawkins: The Selfish--But Very Confused--Gene
- Reading Number Eleven -
Dawkins: Blind Faith in a Blind Watchmaker
Excerpted from: Dawkins, The Blind Watchmaker, Preface and Chapter 2*
Richard Dawkins is an evolutionary zealot, a crusader for the cause of stamping out all doubt about Darwinism wherever he may find it. He has written that anyone who does not believe in Darwinist evolution is either stupid, ignorant, insane, or “wicked.” The title of his book The Blind Watchmaker is an allusion to William Paley’s argument that just as a watch needs a watchmaker, so organisms, with all their fine-tuned complexity, need a designer. Dawkins says natural selection made us, even though it is unintelligent (it is “blind”).
[From the Preface] “Our own existence once presented the greatest of all mysteries,” but Darwin and Wallace solved that mystery, “though we shall continue to add footnotes to their solution for a while yet.”
Yeah, we saw the brilliance of Darwin in earlier readings. Guess evolutionists haven’t advanced much since his time either, if they’re only “footnotes.”
[From Chapter 2] “Natural selection is the blind watchmaker,” an unintelligent process whose creations nevertheless “overwhelmingly impress us with the appearance of design.” This is a paradox, but in this book I aim “to resolve this paradox to the satisfaction of the reader.”
Some of us are more easily satisfied than others, of course. I think I can confidently say that most atheists will be satisfied that Dawkins has resolved all questions by about the first few pages of Chapter 3.
For an organism to be designed means that “it has attributes that an intelligent and knowledgeable engineer might have built into it in order to achieve some sensible purpose,” for example walking, flying, reproducing, etc. “It is not necessary to suppose that the design of a body or organ is the best that an engineer could conceive of...”
Here, annoyingly, Dawkins undercuts an argument we atheists often make (Bertrand Russell did, as we’ve already seen), namely that the universe cannot have been designed because in its current state it does not appear to be perfect—in other words, the argument that design equals perfection. Oh well. Feel free to ignore Dawkins’ embarrassing faux pas here.
Let us do an experiment. Put a monkey at a typewriter with only the 26 letters of the alphabet and a space bar on it. Then let’s see how long it takes him to type the sentence (from Shakespeare’s Hamlet), “METHINKS IT IS LIKE A WEASEL” “The chance of it getting the entire phrase of 28 characters right is... about 1 in 10,000 million million million million million million.” So the chances of randomly generating that sentence all at once are negligible. But what if we try “cumulative selection”? We program a computer to randomly generate a string of letters, then generate copies of it with mutations. “The computer examines the mutant nonsense phrases...and chooses the one which, however slightly, most resembles the target phrase, METHINKS IT IS LIKE A WEASEL.” More copies are generated from this mutant and the best one chosen from those copies, and so on for generations. Well, I tried it on my computer. The random “sentence” it started out with was pure gibberish, of course, but after several generations of reproducing with mutation and selection, “the target was finally reached in generation 43.”
Wow, cool! The power of cumulative selection, huh? Complex information (analogous to, for example, the information found in DNA) generated in only 43 generations! However, after all this, Dawkins adds one caveat:
“Although the monkey/Shakespeare model is useful for explaining the distinction between single-step selection and cumulative selection, it is misleading in important ways.” The computer knew what the goal was—the target sentence it was aiming at. “Life isn't like that. Evolution has no long-term goal,” no target result. Evolution selects only for the ability to survive and reproduce in the present moment.
So Dawkins’ caveat is: the weasel example doesn’t show us how evolution works after all! It’s basically pointless (except of course for answering the burning question—in case you were wondering—“Can a computer be intelligently programmed to generate the phrase ‘METHINKS IT IS LIKE A WEASEL’?”). So Dawkins switches to a different illustration. This time the computer generates pictures, and the selection is performed, not by the computer, but by a human being looking at the pictures as they are generated.
“The human eye has an active role to play in the story. It is the selecting agent... The human eye is here doing exactly what it does in the breeding of pedigree dogs or prize roses. Our model, in other words, is strictly a model of artificial selection, not natural selection.”
Well, another computer model bites the dust. Dawkins still has not come up with something that accurately models natural selection (as opposed to selection that is “artificial,” meaning it is intelligence-driven). But still Dawkins tries to salvage some usefulness from it...
“In the computer model, on the other hand, the selection criterion is not survival, but the ability to appeal to human whim. Not necessarily idle, casual whim, for we can resolve to select consistently for some quality such as 'resemblance to a weeping willow'. In my experience, however, the human selector is more often capricious and opportunistic. This, too, is not unlike certain kinds of natural selection.”
“Not unlike,” huh? And what does this computer process come up with? Digitized ink blots, which sometimes resemble animals or other objects, much as a cloud might resemble...a weasel.
“...The point of the story is that even though it was I that programmed the computer, telling it in great detail what to do, nevertheless I didn't plan the animals that evolved, and I was totally surprised by them when I first saw their precursors.”
There you go. It must have been a pretty faithful computer simulation of natural selection after all, because Dawkins was...uh, “surprised” at the visual designs it could create (some of which looked like “animals”). Moving right along to the evolution of real animals:
“...How did wings get their start? “...if prototype wingflaps worked to break the animal's fall, you cannot say 'Below a certain size the flaps would have been of no use at all'. Once again, it doesn't matter how small and un-winglike the first wingflaps were. There must be some height, call it h, such that an animal would just break its neck if it fell from that height, but would just survive if it fell from a slightly lower height. In this critical zone, any improvement in the body surface's ability to catch the air and break the fall, however slight that improvement, can make the difference between life and death. Natural selection will then favour slight, prototype wingflaps. When these small wingflaps have become the norm, the critical height A will become slightly greater. Now a slight further increase in the wingflaps will make the difference between life and death. And so on, until we have proper wings.
So at some point in the evolution of birds they had no wings, but they were constantly falling to their deaths from trees (or from wherever), to such an extent that as soon as some slight means of slowing their fall came along (a mutation which helpfully gave them small flaps), they began surviving (barely alive, mind you, but they eventually recuperated and went on to reproduce) if they fell from heights of, say 13 feet or less, while their unflapped brethren would die at anything over 12. So common were deaths from falling that this gave the flapped critters an advantage, and they began to out-reproduce the unflapped ones, who were also such evolutionary laggards that they couldn’t keep up by evolving to become less clumsy climbers or evolving to become smart enough not to climb trees (or at least not climb so high, or in high winds, or whatever their problem was). Finally the flapped critters completely replaced the unflapped ones. And then it happened again. And again and again. At first, deaths from falls of more than 13 feet were still very common, but some of the critters’ flaps mutated to a larger size, and they could now survive falls up to 14 feet. Smaller flaps were now out of fashion, and soon all but the critters with the larger flaps had died off. Then came the amazing 15-foot flap, then the 16-foot one, etc. And all this while none of the critters ever happened to evolve any other way of dealing with their falling problem (remember, falls had to be a significant factor in deciding who lived and died, particularly falls in the narrow one-foot zone where flap size made a difference). But are there really animals that fall to their deaths with such consistent, unheeding regularity? Why, sure there are. What we have here is positive proof that birds evolved from...lemmings! We have to remember that it’s simply an article of evolutionary faith that any feature giving some slight advantage, no matter how tiny, will tend to give its owners complete domination over the species (otherwise, how can you explain how the feature evolved?). If an ape with eyelashes is born into a population of apes with no eyelashes, that ape’s progeny will, by our creed, eventually come to rule the ape world solely by dint of its mighty eyelashes! This we believe by blind faith.
* “Excerpts” are paraphrased, except for “words in quotation marks and italics,” which are direct quotations from the excerpted work.
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