Editor’s note: Dr. Axe is the author of Undeniable: How Biology Confirms Our Intuition That Life Is Designed. His contribution to the forthcoming volume, Theistic Evolution: A Scientific, Philosophical, and Theological Critique, is “Three Good Reasons for People of Faith to Reject Darwin’s Explanation of Life.”

In the previous part of my conversation with my friend Hans Vodder, a theistic evolutionist, I questioned his claim that we can’t rule out chance as an explanation for something unless the probability of chance working can be calculated accurately. “If your reasoning is correct,” I said, “then we have no basis for thinking the Mars rover won’t stumble upon what appears to be a working communications device on Mars — one that isn’t of human origin. And if it did, we would have no basis for thinking the device isn’t a natural product of Martian geological processes.”

In other words, I offered a counterexample — something we’re all sure can’t be explained by chance despite our inability to perform anything approaching an accurate probability calculation. I ended with the question: “Does your position still seem reasonable to you, cast in that way?”

Here is Hans’s reply:

When cast that way, no, my position doesn’t seem reasonable; but then again, I wouldn’t put it that way!

I’ll concede this: With the communication device, we don’t need to run the numbers. We can tell, in a rough-and-ready sort of way, that those objects are designed because we can compare them against our background knowledge of what human designers and their artifacts are like. As philosopher Elliott Sober puts it:

“In the case of mousetraps, Mount Rushmore, and Elvis posters [and, I would add, communication devices and adjustable wrenches], we are confident about intelligent design because we have strong evidence for human intelligent design. We know that all of these objects are just the sorts of things that human beings are apt to make.” (Sober, “Intelligent Design and Probability Reasoning,” p. 77)

So, I’d agree with you (although on different grounds) that in some cases, our design intuition “is fully justified even without numerical estimates of the probabilities.” (Emphasis in the original; Axe, Part 5.)

However, it’s a bit different with eyes and dragonflies. While there are some resemblances between organisms and human artifacts, the “match” is more ambiguous. A living system remains “natural” even though it shares qualities with particular human artifacts.

Is there a way to resolve the ambiguity? Absent some definitive hallmark of design (like functional coherence), I’m not sure. We might simply have to run the numbers and see if neo-Darwinism outstrips the universe’s probabilistic resources. However, I stand by my earlier statements and remain skeptical we can do this with any kind of accuracy.

So, the bigger question is: Is functional coherence a definitive hallmark of design?

I don’t think so. My biggest concern (and there are others) is that the description of “functional coherence” given in Undeniable is nebulous. If a dragonfly is fantastically improbable in consequence of its being an “example from a category of things… defined by what I call functional coherence” (Axe, Part 4), then it’s imperative we know in a definite, precise way what functional coherence is. But our discussion of Oklo shows the concept is far from clear.

There’s progress here, Hans. It may seem small, but your concession that we don’t always need numerical probabilities takes us that much closer to agreement. Thank you!

Now, I wonder if you can flesh out in more detail your reason for agreeing with me that the device on Mars would have to be a product of intelligent design. The only two facts I gave you were that this device appears to perform a communications function and that it wasn’t made by humans. That first fact alone seems to have been enough for you to conclude with confidence that the thing was intelligently designed, despite the extraordinary implications.

It can’t be quite as simple as saying “That’s the sort of thing humans do,” because humans do all kinds of things, some of which certainly can be done by ordinary physical processes. We blow the seeds off dandelions, but so does the wind. We stack wood, but so do the waves on the shore. We carve away at mountains, but so do glaciers. We arrange three-letter words in alphabet soup, but so does the soup, every now and then.

Your own decision on this shows that there must be something that distinguishes certain human accomplishments from others, and that this must be obvious enough that it doesn’t require careful analysis or calculation. Whatever it is, it must extend to non-human activity, because you just granted that extension. And it seems it must be implied by the two words “communications device,” because that’s all you had to go on.

So, what is it?

Photo credit: Frank Winkler, via Pixabay.