Irreducible Complexity.

[CoxRox]

Leo, the original definition by Behe states:
''A single system composed of several well-matched, interacting parts that contribute to the basic function of the system, wherein the removal of any one of the parts causes the system to effectively cease functioning.'

William Dembski's defines it as:
''A system performing a given basic function is irreducibly complex if it includes a set of well-matched, mutually interacting, nonarbitrarily individuated parts such that each part in the set is indispensable to maintaining the system's basic, and therefore original, function. The set of these indispensable parts is known as the irreducible core of the system.''

I understand the part you have highlighted in bold seems to be disagreeing with what I said in my previous post. Dembski states:
'A system is irreducibly complex in Behe's sense if all its parts are indispensable to preserving the system's basic function. That an irreducibly complex system may have subsystems that have functions of their own (functions distinct from that of the original system) is therefore allowed in the definition'.

http://www.designinference.com/documents...sponse.htm
So the wording in bold is I believe misleading.

I do not understand target function. Is it to do with mathematics? Why do you ask?

Adrian- are you saying that the syringe is a separate new function, and that the flagellum still operates fully, if you take parts away or are you saying that by taking parts away you get a new function- hence the syringe and then you no longer have a fully functioning flagellum? I had a brilliant article regarding this which I have spent the last two hours trying to find and can't. I will come back to you on this.

[leo-rcc]

I do not understand target function. Is it to do with mathematics? Why do you ask?

Well you brought it up in your previous post so I want to know what you mean by that.

[CoxRox]

Oh right. I understood target function used here to mean the target or end purpose of it's function ie all the various parts once assembled produce the function for which they were assembled together. I didn't realise this term is used in mathematics, hence why I was stumped. I've edited my last message, by the way.

[CoxRox]

I've found some information regarding the syringe from Miller himself:
'This means that a portion of the whip-like bacterial flagellum functions as the "syringe" that makes up the Type III secretory apparatus. In other words, a subset of the proteins of the flagellum is fully-functional in a completely different context – not motility, but the deadly delivery of toxins to a host cell. This observation falsifies the central claim of the biochemical argument from design – namely, that a subset of the parts of an irreducibly complex structure must be, "by definition nonfunctional."

http://www.millerandlevine.com/km/evol/d...ticle.html

I think I've established that this is an incorrect assumption by Miller regarding subsets having a function of their own.

[bozo]

I've found some information regarding the syringe from Miller himself:
'This means that a portion of the whip-like bacterial flagellum functions as the "syringe" that makes up the Type III secretory apparatus. In other words, a subset of the proteins of the flagellum is fully-functional in a completely different context – not motility, but the deadly delivery of toxins to a host cell. This observation falsifies the central claim of the biochemical argument from design – namely, that a subset of the parts of an irreducibly complex structure must be, "by definition nonfunctional."

http://www.millerandlevine.com/km/evol/d...ticle.html

I think I've established that this is an incorrect assumption by Miller regarding subsets having a function of their own.

CR, I'm mixing threads here but I need to ask you something.
You introduced yourself to the forum as a " doubting christian ".
On the " Is faith a cop-out " thread, given 3 choices you picked " God has always existed ".
My question is this, you appear to WANT to believe in " God ", so how are we atheists any help in fulfilling your desire? Are you on the right forum?

[Edwardo Piet]

Maybe, Coxrox, you should check out reductionism: http://en.wikipedia.org/wiki/Reductionism
I myself am a reductionist. To be more precise in my beliefs, which I haven't done on these forums before (well not this precise I am a:
Monist Materialist Reductionist Neo-Darwinian De Facto Atheist practicing TAP (Temporary Agnosticism in Practice).

[Tiberius]

Adrian- are you saying that the syringe is a separate new function, and that the flagellum still operates fully, if you take parts away or are you saying that by taking parts away you get a new function- hence the syringe and then you no longer have a fully functioning flagellum? I had a brilliant article regarding this which I have spent the last two hours trying to find and can't. I will come back to you on this.

The whole thing that you must remember here is that both the flagellum and syringe are made up of different proteins. In different arrangements, these proteins do different things. I'm trying to come up with an analogy that you can understand, but so far I seem to have failed miserably (my fault entirely).

The mousetrap is a good example though, so I'll try to explain it a bit better. A mousetrap consists of 5 pieces: a board, pin, hammer, spring, and latch. Separately, these can do jobs on their own. For example, the board could be used to draw straight lines with a pen, the pin could be used to hold things up against a noticeboard, the spring in a clothes peg. Furthermore, arrangements of these elements can also form specific jobs. For example, the hammer, spring, and board make a very nice tie-clip; the latch, board, and pin could be used as a rudimentary notice board (using the latch to hang it).

So if we agree that Behe meant that I.C means that if any of the parts are removed, the entire original function (in this case, the ability to catch mice) ceases to function, then I have no problem with I.C. Certainly there are many things that could work for this definition.

The problem lies within Behe's attempts to use this as a "proof" that Evolution cannot occur for these systems. As he allows subsets of elements to have their own functions, there is no reason why a combination of the subsets could evolve to form the entire set.

Imagine that the mousetrap elements are natural and can evolve for a moment.

Say we have an organism that has a notice board attached to it (for whatever reason), so the board and the pin are in place. The organism could also have a tie-clip appendage (spring, board, and hammer) in some place. A mutation takes place that adds the tie-clip to the notice board. Now, although annoying, the noticeboard can still be used as such (you can still stick things to it if you avoid the hammer), and the tie-clip can likewise still be used. Neither of the functions have been destroyed. Another mutation takes place, adding a latch that locks the hammer in place. The function of the tie-clip is suddenly destroyed, but the mousetrap function is born. If the mousetrap function is better suited to keep the organism alive, it will be chosen by natural selection, and be passed on.

*phew* I've just explained evolutionary biology with mousetraps.

Hopefully you can visualize this. Otherwise I'll have to resort to drawing it

[CoxRox]

Bozo, you said:
'CR, I'm mixing threads here but I need to ask you something.
You introduced yourself to the forum as a " doubting christian ".
On the " Is faith a cop-out " thread, given 3 choices you picked " God has always existed ".
My question is this, you appear to WANT to believe in " God ", so how are we atheists any help in fulfilling your desire? Are you on the right forum?'

I am here because I have enough doubts that motivate me to check things which supposedly support ID. I am aware that ID supporters are in the minority and I cannot ignore the majority of very intelligent people (many atheists e.g Dawkins) who do not 'see' ID in things like we are discussing in this thread. I think it's important to get 'both sides' views and arguments in order to be sure. I know there is a possibility there is no 'God' and that my reasonings etc are faulty. The folk here have already opened my eyes, as it were to a 'bigger' possibility that there is no God.
Hope that explains why I am here? By the way, happy birthday

Evidence- my brain has nearly short circuited with your revelations of your exact position. I'll try to decipher it when I get a chance.

Adrian, you said:
'I'm trying to come up with an analogy that you can understand, but so far I seem to have failed miserably (my fault entirely).' I think the fault may be with me, in that I don't understand biology stuff that well, and so maybe this post is going to prove too much for me. I may have bitten off more than I can chew so to speak. I see what you are saying: these smaller 'machines' ie the syringe, come together gradually and produce more complex things ie the flagellum? Is that right? I spent a good few hours yesterday reading up on this bloody flagellum, and IC. Actually the flagellum is amazing and would put Mazda to shame. Some of the articles I read were seeming to say that IC does not preclude gradual evolution, but I haven't read enough about this and to be honest i think the main supporters wouldn't agree with this. I'm going to email the man himself, Behe regarding a few points. I've emailed him before and he responded within a few days. I will ask for a reprieve at this point while I recheck some things, see if Behe can get back to me, and hopefully tie this thing up. Hope that is ok.

[leo-rcc]

Allow me to speed this along if I may.

"irreducible complexity" was actually first posited not by Behe, but by the evolutionary biologist Hermann Joseph Müller in 1918. He didn't actually invent the term, but he certainly invented the concept, which first appeared in the following scientific paper:

Genetic Variability, Twin Hybrids and Constant hybrids in a Case of Balanced Lethal Factors by Hermann Joseph Müller, Genetics, 3(5): 422-499 (1918)

http://www.pubmedcentral.nih.gov/article...id=1200446

Scroll down to page 464, and read on to near the end of the first paragraph of page 465, which reads as follows (relevant part highlighted in bold):

Hermann Joseph Müller wrote:Most present-day animals are the result of a long process of evolution, in which at least thousands of mutations must have taken place. Each new mutant in turn must have derived its survival value from the effect upon which it produced upon the 'reaction system' that had been brought into being by the many previously formed factors in cooperation; thus, a complicated machine was gradually built up whose effective working was dependent upon the interlocking action of very numerous different elementary parts or factors, and many of the characters and factors which, when new, were originally merely an asset finally became necessary because other necessary characters and factors had subsequently become changed so as to be dependent upon the former. It must result, in consequence, that a dropping out of, or even a slight change in any one of these parts is very likely to disturb fatally the whole machinery.

This was placed on a rigorous footing by the 1930s, which means that evolutionary biologists have known Behe's canards about "irreducible complexity" to be canards for over six decades, which means that "irreducible complexity" as posited by Behe was dead in the water among real scientists before Behe was born.

Thence we come to the Müllerian Two Step which as the TalkOrigins link states, is represented by the following:

[1] Add a component;

[2] Make it necessary.

Which of course means that "irreducible complexity", as well as first being proposed as a concept by an evolutionary biologist, was also proposed not as a problem for evolutionary biology, but as a natural outcome of evolutionary processes. Behe has failed to recognise that he was pre-empted to his "big idea" by an evolutionary biologist 80 years before he started selling his soul to that speciation variant of creationism that has been caught stealing a lab coat, Intelligent Design.

Of course, the limits of Behe's canards extend beyond the misappropriation of Müller's work for creationist ends. Another more insidious canard that Behe propagates is the specious notion that any evolutionary change necessarily requires that the organism carrying the mutations must be optimal at every stage of the transition to the final state otherwise it will die. This is manifest nonsense - all that is required is that the mutations are insufficiently deleterious to impair the organism's ability to produce descendants. Even a mildly deleterious mutation, if built upon at a later stage by a second mutation whose effect, when synergistically coupled to the first, is one of net benefit, will suffice for the task.

Evolution doesn't require that every organism functions with Rolls-Royce elegance and finesse from the word go: it merely requires that organisms function sufficiently well to produce descendants, even if that functioning happens to be the result of, to continue the automotive analogy, a cut-and-shut job involving the front half of a Pontiac Aztek and the back half of a Ssangyong Rodius, which as any regular visitor to the Car Talk website in the States will know, are listed as being among the most hideous cars ever to take to the road.

But they function as cars. The hideous cut-and-shut vehicle I described above would be a crock, and I wouldn't want to drive one, but someone with a taste for dangerous living might find it suffices until such time as something less likely to be lethal turns up at the local car lot at an affordable price. Likewise, an unstable crock of mutations, if it functions well enough to produce descendants, can provide evolution with an unexpected opportunity if the right mutations turn up and produce something far more robust and elegant from the inauspicious beginnings.

Behe, however, mendaciously insists otherwise, despite the fact that mountains of evidence known to the real scientists refutes his duplicitous bait and switch wholesale. His notion is tantamount to suggesting that the cut-and-shut crock of a car I've described above would never work, and the only cars that would ever function would be the pristine products of Rolls-Royce, Bentley, Bugatti, Mercedes-Benz and Ferrari. Millions of lesser cars that do enough to get by make a mockery of that notion, and likewise, millions of lesser organisms that do enough to get by make a mockery of his insidious lie, that evolution can't achieve anything substantive because it can't produce the biological equivalent of a Bugatti Veyron at every step.

Evolution doesn't need to, and in any case Behe's assertion itself may yet be falsified further if scientists alight upon an evolutionary sequence in some organism at some future stage that delivers just that - a Bugatti Veyron at every stage of the process - in which case the amount of humble pie he will be required to consume will probably prove lethally toxic. Of course, the scientists don't need to deliver such a discovery, but oh, the joy we will all have seeing Behe's nonsense made even more absurd by observational reality should the scientists do just that!

With thanks to Cali for pointing out the scientific papers and links and helping me make sense of things.

[Edwardo Piet]

Very interesting, thanks leo.