Dennis and Bill asked about detectability of design. Why does this matter? they wondered.
The answer can be found in what Dennis wrote in this same thread:
"In principle I'm open to the idea that God could have used miraculous means for parts of natural history. I just haven't yet seen evidence that suggests to me that this is the case."
If we allow that a type of cause could have acted, then -- whether it did or not -- we must also be able to detect that cause. Dennis allows that God could have acted by using what he calls "miraculous* means," although Dennis has yet to see sufficient evidence of that mode of acting. In other words, Dennis says that detectability of design is possible, given the right evidence. [*See the end of this comment for an important clarification about the term "miraculous," when applied to designed events.]
Interestingly, these philosophical allowances place Dennis within the ID community. The bare possibility of the detectability of design marks the outer boundary of the ID research community. Now, Dennis is standing right next to the boundary -- his toes, maybe, touching the chalk line -- nonetheless, while he is a strong skeptic and critic of ID reasoning, he awaits the sufficient evidence of design, because (a) he admits such evidence may exist, and (b) if it exists, he must also be able to detect it reliably.
From discussions at the ETS/EPS annual meeting this past week, I think many BioLogos supporters are also standing where Dennis is, just inside the chalk line. In other words, they remain unpersuaded by the current empirical case for ID, but allow that, if a better and more well-supported case could be made, they'd move closer to the center. Despite what you may believe, Ann and I highly value critics such as Dennis, because without them making us work harder to improve our thinking, we'd become complacent.
Note to Jonathan Burke: many evolutionary biologists doubt universal common descent, so Discovery Institute isn't much of an outlier in that regard. See my chapter, "Five Questions Everyone Should Ask About Common Descent," in the new Crossway Anthology, Theistic Evolution (2017), or check out recent publications like this (nota bene the last sentence of the abstract, and the first sentences of the paper itself, which is open access):
*About the adjective "miraculous." Think about what you're doing right now -- maybe, composing an email, or drafting a comment to post in this thread. Or just doodling on a piece of paper near your computer. What you are doing (i.e., the observable effects you are causing in the world) is in no sense "miraculous" or "supernatural" -- but neither can it be explained by strictly physical processes, without referring to your intelligent agency. In other words, to divide up the universe of possible causes into the "natural" versus "miraculous" or "supernatural" is an unsound analytical cut. Agency is perfectly real, but it does not collapse into the strictly physical.