Monday, May 06, 2002

Creating a theory - part III

If you've been following this succession of posts, several of us have been discussing the theory of evolution on its own merits, without reference to religious alternatives. It can be awkward to follow, because the comments I am addressing below are found under another blog item here.

I must say, I admire Paul Orwin's faith in things unseen when he says "I think intelligent design theory is another incarnation of the 'God of the Gaps' theology, which will die a slow and painful death as the gaps are closed". This looks like antipathy to me - why?

Doug Turnbull notes that bacteria adapt to antibiotics, showing characteristics that weren't there before. And how does that happen? Is it totally dependent on random changes in the genome? That would appear to offer an infinite number of possibilities, which even bacteria are not prolific enough to generate. But if these mutations are not totally random, what guides them? How can a cell zero in on the most effective mutations in a finite time in order to survive?

I don't agree with DT's assessment of astrophysics under my criteria. Science deals in what is useful, not in what is true, and astrophysics has generated some useful results. What's more, much of it works with phenomena well known here on earth, such as relativity, red shifts, gravitation, etc. And the consequences of being wrong are not great in any case, with the possible exception of predictions of the life of the sun, or the paths of objects that might collide with the earth.

But on the edges, when it uses a century or two of observation to predict what will happen billions of years from now, it's dodgy and should be recognized as such. It's as if you were given a minute to observe a species unlike any on earth and expected to be able to tell how old it was and how much longer it would live.

As for the videotape comment, we'd ask for something like that for about anything else in the hard sciences. Don't tell me this reaction occurs, show me, and then another lab had better be able to duplicate it too. If I tried to beg off saying the process took too long, you might rightly think me a charlatan, or at best you might withhold judgment. Perhaps such standards are inappropriate in this setting, but there's nothing unfair in asking for demonstrations per se.

DT says this: "If you really think it's reasonable to believe that every species on earth now has always been present as it is to believe in the theory of evolution, then I'm not sure any argument is really possible." Maybe so, but that's not because I'm being unfair. I believe that those who postulate that some species weren't here from day one implicitly assume the burden of demonstrating that that is true.

As for extrapolation, I will dedicate an entire post to this later.

DT also says that evolution is the only testable hypothesis that explains said data. OK, what other hypotheses were tried and found wanting?

DT notes that certain sections of DNA don't seem to code for anything, and thus can be used as a timer of sorts based on rates of accumulations of mutations over time. How do we know that these sections don't code for anything? Genomes are very complex and we don't understand them yet. Are we now prepared to say that no use will ever be found for these sections that don't seem to code for anything under our present knowledge, and that these mutations don't serve some subtle determinate function unknown today?

I have read various books about chaos theory and have been amazed at some of the complex emergent behavior arising from unexpected places. I have to wonder what yet is to be found in the genome, and if it's possible that the diversity and resilience of life results from the emergence of behavior encoded in DNA from day 1.

The arguments that really floor me are the ones that attempt to use what could be called design features to disprove design arguments. As I see it, this amounts to postulating an omniscient, omnipotent Creator, and then arguing with Him - "ya shoulda done it this way!". I can be an arrogant SOB, but if I thought such a being existed, I'd happily defer to His judgment and would hope to learn from it. And I'd do a lot of experiments to figure out how He did things in hopes of staying on His good side or guessing what He might do next - science would be an essential part of my religious practice.

I'll ask religious people to abstain from commenting on this post (send me email if you want). I respect your beliefs, and you're welcome to comment elsewhere. But I have found that your presence in such discussions leads in unproductive directions, and I ask for your indulgence in this. Thank you for your understanding.

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