Donald: <<Please explain. Why do you say this?>>
For instance lungs appear to not have started off as such.
>Donald Hows: << An arch, if it not used to support things, is a rarity. If
we assume that an arch is used to support things, like bridges, then a half
made arch is no arch at all.>>
>
>But the bridge is built step by step. Only in the end does it serve to
support ?
>
Donald: <<What does a bridge do when it's only been built the first few steps?
Assuming that it will take many generations to build this bridge, and that
no-one know's what it will do in the end, what does it do? Why have one,
why make one? A lot of effort and a lot of bricks for nothing. That's what
irreductbly complex is all about, it's useless untill it's finished.>>
Not necessarily. What about a football stadium with a vaulted roof. Even while the roof is being built, the stadium can serve its purpose, just no roof and when it rains, the field gets wet.
Irreducibly complex presumes that there is no use for intermediate steps. But that can easily be shown to not be a requirement. Note that it might still be correct but it should not presume but show that intermediate steps could not have a purpose
>Howes: << I think this is the logic being used here. If this arch can't
support things, and in fact needs
>supporting, then to suddenly change to being a support would be a strange
thing. I confess that it could get there in small steps, but only if an
intellegent desginer was overseeing the whole thing, with the out come in
mind.>>
>
>Well, at least we agree that Behe's argument is wrong. The only difference
is that you require an 'intelligent designer', without further proof that
this is indeed the case.
>
Donald: <<Behe's argument is that without all the parts there, it's useless. I agree
with that, because even if someone is designing it and overseeing it's
constrution, it will still server no purpose untill completed.>>
The presumption that without all parts, it's useless could be erroneous.
>http://www.talkorigins.org/faqs/behe/review.html shows a pathway through
which an irreducibly complex system could have arisen in small steps with
the functions intact.
>
Donald: <<I didn't see anything that showed a pathway, there was a bad example of a
mouse trap as a irreducibly complex system, that turned out to be not
irreducibly complex. Does this mean that there is no such thing as
irreducibly complex? >>
Nope but it shows that something 'irreducibly complex' can still have its origin in small steps.
But I was refering to the example of the chemical pathway. Perhaps you should look again ? It shows how using small steps the end result is irreducibly complex, yet it was reached through small incremental steps which weren't. That shows that Behe's argument does not hold.
>The fact that removing a piece now leads to a collapse does not mean that
there were no supports in the past that allowed pieces to be added or removed.
>
Donald: <<True, but that still implies that it was useless untill completed, just
like our bridge, and that is Behe's argument.>>
Again, this is not implied but presumed by Behe. Behe's argument is inherently flawed as it presumes that it could not have had any function until completed. The talk.origins page as well as others have shown this argument to be 'meritless'.
Behe might want this to be the case but his argument becomes circular in that he considers a system irreducible if it could not have gotten there through small steps and then calls something irreducible because removing a part makes it fall apart and concludes that therefor it could not have gotten there through small steps.
A severely flawed argument.