From: bivalve (bivalve@mail.davidson.alumlink.com)
Date: Thu Sep 25 2003 - 18:15:05 EDT
>You probably know this but I'll give my take on the issue. Irreducible complexity says that if you take out one piece of a functional apparatus, it doesn't work at all.<
>Now genetics can describe several plausible mechanisms for this to happen: gene duplication, co-opting, and others.<
Problems with this definition of irreducible complexity include determining whether the apparatus minus a piece is functional (not merely whether it achieves the same function) and determining whether the current apparatus accurately reflects its original form (as opposed to a simplified version, like the building with scaffolding removed).
As an illustration of the problems of concluding irreducible complexity, take the citric acid cycle. It is a multistep process requiring all its parts to function as it does. However, some bacteria have one half of the cycle functioning on its own and the other half functioning on its own. Thus, while not being the citric acid cycle, each part is a useful and functional whole. Thus, the citric acid cycle passes the criterion of requiring all its parts to work, yet it is easily assembled from simpler, useful components.
All known living organisms appear to share a common ancestor with a fairly complex system already in place, so for many features we may be forced to rely entirely on recreation of possible ancestors, without hope of finding the equivalent of the two pieces of the citric acid cycle.
>However, the question is not even really one of mechanism, because it could even be stipulated that these "natural" genetic process could be guided somehow. The real question is one of probability and information theory. Do non-telic forces have enough informational power to create the complexity we see?<
To answer this question, we need several pieces of information that we do not have. These include knowing the structure and function of all the parts of the system under consideration, the similarities of these parts to others (so as to give ideas about possible functions of the component parts that would have to be assembled), and what alternative methods might exist (e.g., we might be less impressed with the complexity of the citric acid cycle if we found out that there were billions of easily assembled ways to achieve the same molecular result, several of which were simpler and more efficient than the one we observe).
I would agree that we do not have the scientific information to conclude that non-telic forces could create all the complexity that we see. Nor do we have the scientific information to conclude that they could not. I suspect that non-telic (in the proximal sense but ultimately under God's control) forces are adequate, and I see clearly bad arguments being used as examples of irreducible complexity. At the same time, I see clearly philosophically motivated rejections of intelligent design.
Dr. David Campbell
Old Seashells
University of Alabama
Biodiversity & Systematics
Dept. Biological Sciences
Box 870345
Tuscaloosa, AL 35487-0345 USA
bivalve@mail.davidson.alumlink.com
That is Uncle Joe, taken in the masonic regalia of a Grand Exalted Periwinkle of the Mystic Order of Whelks-P.G. Wodehouse, Romance at Droitgate Spa
This archive was generated by hypermail 2.1.4 : Thu Sep 25 2003 - 18:15:14 EDT