Is convergent evolution evidence against common descent?

WK, your link is missing.This message has been edited by Parasomnium, 07-Jun-2005 10:52 AM

Rrhain may be capable of many things, but no one, including Rrhain, is able to throw a handful of coins in such a precise manner that they land exactly the way it was calculated before throwing them. Indeed, no one is able to make the calculation itself. So Rrhain's intelligence is irrelevant in this instance. But you knew that already because it was pointed out to you here. In this instance, intelligence is relevant because it takes intelligence to reproduce the pattern of coins. What Rrhain wanted to show you, is that a pattern that looks just like a random pattern but was meticulously placed that way by an intelligent agent, is indistinguisable from a real random pattern. So, if you claim that an Intelligent Designer made it look like life developed via evolution, i.e. via a natural process, then there is no way we can verify that. That makes the claim vacuous. It seems you are equivocating evolution with all of nature, but I'll let that slip. I think I know what you mean to say: intelligence and artificiality are part of everything, they exist. If evolution is true, then intelligence and artificiality must have come about via that process, they are part of that natural process. Is that what you're saying?For the moment, I'll assume it is.My problem with this is that you seem to make the jump from human intelligence to intelligence in general. From the fact that human intelligence exists and is part of nature, you conclude that therefore intelligence in general is part of nature, including the intelligence of an Intelligent Designer, although you don't say the last part out loud. The main problem is then of course that the intelligence of the Intelligent Designer must also have evolved, before the process of evolution itself was set in motion by it, or was emulated by it, or whatever.You do the same thing with willful choices: human willful choices exist, therefore willful choices exist, therefore evolution is governed by willful choices.Needless to say, this is faulty reasoning. Unless that is not what you wanted to say, of course.This message has been edited by Parasomnium, 08-Jun-2005 09:53 AM

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We are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further. - Richard Dawkins

I completely agree. Life looks designed. In fact, I'll go even further: life is designed. Bear with me, I'll explain.But first, this: I agree again, it looks like there is an intelligence behind it. But this time, I'll not go further than that, this is where we part company. Because you think that if it looks like there is an intelligence behind it, the only possible explanation is that there is an intelligence behind it, whereas I think that evolution, a mindless process, is another possible explanation for design. Design doesn't need intelligence to arise. I'm not saying that intelligence is out of the question, simply that it isn't necessary. Also, it needlessly complicates matters, because, apart from being a possible explanation, it needs to be explained itself as well. If I have the choice between two possible explanations, one of which is more complicated and contains unnecessary elements, I choose the simpler one.As I said, life is, indeed, designed. I will not deny that the eye, for example, exhibits a lot of design: a variable lens, a variable aperture, a light-sensitive layer, shutters, the works. A really nice piece of design - though it has its faults: the blind spot for example. (Actually, the concept of the eye is such an important improvement in life that it has evolved independently many times over, in diverse lineages. And guess what? The octupus eye doesn't have a blind spot.)So, how can design arise from the mindless process of evolution? Through natural selection.Time and again, it needs to be explained to creationists and ID-ists that evolution has two major components, not just one. The two are: random mutation and natural selection. Not just randomness - the part that invariably gets creationists in a frenzy - but non-random selection too. Creationists always leave out natural selection and concentrate solely on the apparent absurdity of randomness.Random mutation gives you a nearly endless array of possible traits. If you keep only those traits that don't get you killed before you can reproduce (and throw away all the harmfull traits), you have yourself a nice scaffold for further innovations in the next round of random mutation and natural selection.Random mutation doesn't involve intelligence, that much we can agree on, I think. After all, it isn't called 'random' for nothing. And natural selection is achieved through the organism's fitness for survival in a demanding environment. If you haven't got what it takes, you die. And if you haven't reproduced before you die, your traits die with you. But if you do have what it takes to survive until after you've mated, your traits survive another round. But there's no intelligence involved in what I just described. Selection is simply achieved by not dying prematurely. And my point is that portraying evolution as "random chance without any intelligence or design behind it" is to paint a false picture. As I explained above: first, it's not just random chance, but also non-random selection, and second, although intelligence isn't necessary, there's definitely design to be discerned, evolutionists will not deny this. I left open the possibility that you didn't mean to say what I thought you said. You clearly state that you didn't, so I'll accept that. Apologies for misunderstanding you.This message has been edited by Parasomnium, 08-Jun-2005 10:36 PM

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We are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further. - Richard Dawkins

I'm sorry, but I think that's a misconception. Here's what I said (I've underlined the important parts):

quote:

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I think that evolution, a mindless process, is another possible explanation for design. Design doesn't need intelligence to arise. I'm not saying that intelligence is out of the question, simply that it isn't necessary. Also, it needlessly complicates matters, because, apart from being a possible explanation, it needs to be explained itself as well. If I have the choice between two possible explanations, one of which is more complicated and contains unnecessary elements, I choose the simpler one.

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So you can hardly say that I exclude one explanation over another. It isn't at all obvious that the design in nature predated the physical implementation of it. The many design flaws we find in nature are actually pointing to design arising gradually, "on the job" as it were, continuously adapting itself to new circumstances.And since the process of evolution only allows adaptation in small steps, some major design "decisions", having become a liability in the long run due to changing circumstances, can only be remedied by a work-around, leaving large parts of the faulty design intact. We've learned to live with a blind spot, for example. Even if mutations were not random, you forget that there is another, much more important non-random characteristic of evolution: natural selection. Nosyned gave a nice example in message 4 of this thread: the similarity in form of dolphins and sharks. It seems to me that that's a typical example of natural selection weeding out non-functional aquadynamic forms. If you want to swim fast through water, the best form you can have is the shape of a bullet. So, as far as fast swimmers are concerned, natural selection favours bullet-shaped animals. There's no need for non-random mutation, just non-random selection will do nicely.That's not to say that non-random mutation is impossible, of course. Testing for it and finding it adds to our knowledge, as does finding only randomness. Nice of you to acknowledge this, thank you. That's why DNA comparison is such an important scientific improvement in biology. It allows us to check classification based on other methods and sometimes correct mistakes made therein. That's how science makes progress. I have yet to see ID do that.

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We are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further. - Richard Dawkins