He's not a scientist. For example, the fact that you don't have every single organism that represents an example of the evolution of a trait is not at all damning, and to expect it is ridiculous.
Right. Science is a method: you work with the data you have, or can get. Of course there are going to be gaps, just like, on a graph, you have to norm dots into a trend-line. Nobody looks at a hitter's batting average, sees that the guy rode the bench for two days, and says, "Well we just don't know how good a hitter he is, do we?"
To supplement Bon Bon's analysis (quoted parts are Dembke):
Is Orr saying that evolutionary theory is in the business of telling historical narratives that are purely subjective.
No. Orr is saying that ID-proponents like Behe are constantly changing the finish-line, by saying, "Oh no, sorry, that's not a detailed enough explanation for me. You lose!" Whether that's so or not, I don't know, but in that sentence Dembke is misrepresenting what Orr is saying, by dint of misconstruing a subordinate clause.
The whole rest of that graf is repetition of Behe's original point, and fails entirely to engage with Orr's counterpoint, because Dembke failed to parse the sentence he's rebutting correctly. Thus, Dembke is basically saying. "Does Orr have a point? Who knows! But I do know my point, which is..." Verdict: marathoning (repeating your point while failing to engage your opponent's point) = shitty argumentation.
THOROUGHLY DARWINIAN???
Anybody who uses all-caps in professional writing needs to be taken out behind the barn and whupped. Preferably by his mother. Lacking a living parent, the condemned may be assigned yours truly for his punishment. Verdict: My foot in somebody's ass.
This is technological evolution, with each point in the process superintended by intelligence. Moreover, the changes at any stage are hardly gradual — a GPS placed into an automobile does not fall under what Darwin called “numerous, successive slight modifications.”
This strikes me as a (potentially intentional) misunderstanding of Orr: Orr is using GPS devices in cars as an analogy for the "extra becomes essential" mechanism. Of course GPSes are supervised by intelligence. But that's not the point: the point is, 50 years from now, your car will not be able to drive itself without a GPS. Something got appropriated (by whomever) away from its original (cool toy) purpose, and put to a different use (automated navigation). Who did the appropriating is not what Orr is arguing: he's arguing that the appropriation is a mechanism that makes problems for the whole idea that something is "irreducibly complex." Dembke is seizing on the details of Orr's analogy, rather than comprehending its larger point. Verdict: Red herring (a distracting side-issue that takes attention away from the main issue) = shitty argumentation.
To reiterate, Orr does not appreciate that ID theorists are not asking for actual historical narratives. They are asking for detailed Darwinian pathways that could have produced the complex biological structure in question (should these also serve as historical narratives, fine, but that’s not and never was the issue).
I can't make heads or tails of this one. Orr is providing various potential pathways throughout his essay, by analogy for a lay audience. If ID is asking for them, then ID has been answered, so... what's to argue? I presume that Dembke is asking for something more detailed and [Nutty forgets most of her biology] than Orr provides, but, Orr is writing for the New Yorker, so of course he's not going to provide details. New Yorker articles are long and boring enough!
It's possible that what Dembke is asking for is something that all of science can't provide, but -- he doesn't explain why what Orr does provide isn't good enough. Also, see above with the "constantly changing the finish-line" issue, which Orr tries to address (and which Dembke refuses to address). Verdict: Marathoning + a bit of the straw man (continued...)