Jejudo, South Korea
Brad, you're doing it again ... minimizing the difference between a finch's beak changing size, and a light sensitive spot becoming a seeing eye.
Well, you're doing it again too. What I'm comparing is the slight difference in a finch's beak size to a slightly more sensitive 'light spot'. Over time, say two or three million years, these processes can turn into the beak of a giant moa or the eye of a fish.
Here's a quick summary of the intermediate stages for a fish eye:
It's explaining the crossing of a canyon, by illustrating the hopping over a mud puddle ... conveniently sidestepping the benefit of an explanatory bridge. I'm not saying it's impossible ... I'm saying that from a biochemical standpoint, it is astronomically unlikely, and therefore quite far from escaping it's theoretical status.
Randomly, you are correct, but the theory of natural selection is not random. Again, the metaphor of jumping and of canyons, but on evolutionary scales canyons weren't there that are there now. Again, the confusion of time scales.
Nothing points in that direction ... of design? You are in disgreement with a multitude who have "inferred" design. Don't complain too much about the invalidity of inference, if it is after all acceptable enough to make macro-evolution credible without the scientific rigors which provide unambiguous models.
I mean that we haven't found any evidence to indicate a designer, a design signature if you will. Believe it or not, design companies have started putting their own design signatures into their genetic codes. Why not this designer? Have we found a quote from the Bible, say in Hebrew, in any naturally floating DNA? Not yet.
If you start from the assuption of evolution, you have to explain apparant intentionality and artifact after artifact. If you start from a design perspective, they start to make sense.
We see intentionality because we are intentional creatures. Doesn't that make sense? But we have plenty of examples of elegant 'design' resulting from a few well placed instructions. Migrating birds, for example, don't intentionally make that beautiful 'V' shape, they follow a few simple rules that results in a 'V' shape. During the summer, something like five to ten thousand birds (I think they were swallows) perched on the telephone and electrical wires just outside my house, they were beautifully symmetrical. Design? Nah, they had an instinctive space mechanism that didn't allow them to get too close to each other (and indeed they often fought each other over this space). The appearance of design was just that, appearance.
No one denies that change happens. The question is what can Darwin's mechanism do? Yes you are right the idea is warranted ... but not the fact.
Hmmm, maybe we can make some progress here.
I said Darwin's mechanism was a theory for the fact of evolution. Now, I've attempted to defend both, but in the back of my head, this distinction has always been clear. Behe himself says, I think the term he uses is 'fairly convinced,' of common descent. That is, he doesn't dispute that evolution happened, but that the mechanism of natural selection doesn't cover everything. My point is that, even if true, you still don't throw out the baby with the bathwater (as many on your side of this debate seem desperately at pains to do -- not you personally of course).
What seems to happen, then, is the eternal search for the smoking gun, the one knock down argument that proves evolution wrong. But there is no smoking gun, there just isn't one argument that will dislodge it. Take the genetic signature, for example. Let's say you find it in one place, what you then have to do is find it everywhere. This will take time, at least as much time as it has to amass the evidence for evolution.
No one disagrees that we've, in fact, directed evolution in some species for several thousand years. We've changed species and made some go extinct. Does the fact that we've directed, consciously or unconsciously, evolution somehow, negate the fact of evolution?
And you responded:
Are you suggesting that genetic manipulation by intelligent humans provides proof for evolution? That's a quite different situation than random mutation and natural selection. We could just as easily use such examples as proof for design.
But this is a misinterpretation. What I meant was that directed evolution does not in and of itself disprove evolution through natural selection. We already have evidence for both. We're the directors.
While you keep saying "evolution" is the fact ... I would still say you are merely restating the fact of change in biology ... without knowing to what degree, or from what sources exactly. Biodiversity itself is the absolute fact or condition of the world. Neo-Darwinian evolution is still absolutely theory.
Evolution is the process of small changes becoming big changes over time. That's a fact. The Darwinian theory of evolution is that this is accomplished through natural selection. There's a huge amount of evidence to support this theory. Is it complete? Of course not, we have a lot more work to do. If evolution is not all encompassing, if natural selection doesn't fit every situation (and, as I've said, we already know it doesn't), I suspect that it will be those who do the work in evolution that will show this.
Let's let them do the work and see what happens.
Now, I want to end with a return to berengar's point about Design Theory. If we concede a designer, shouldn't we then ask how he or she did it?