In his recent testimony in Kitzmiller v. DASB (archived here, among other places), Michael Behe described what he called an “experiment” that could potentially falsify ID. Reading from his Reply to My Critics article, Behe testified that
In fact, intelligent design is open to direct experimental rebuttal. Here is a thought experiment that makes the point clear. In Darwin’s Black Box, I claimed that the bacterial flagellum was irreducibly complex and so required deliberate intelligent design. The flip side of this claim is that the flagellum can’t be produced by natural selection acting on random mutation, or any other unintelligent process.
To falsify such a claim, a scientist could go into the laboratory, place a bacterial species lacking a flagellum under some selective pressure, for mobility, say, grow it for 10,000 generations, and see if a flagellum, or any equally complex system, was produced. If that happened, my claims would be neatly disproven.
Let’s consider that suggestion for a moment. Is it possible that Behe is right and ID is experimentally testable?
More below the fold.
In this brief sketch I’ll leave aside questions about the details of such an “experiment”. For example, I won’t consider whether 10,000 generations in a lab culture is sufficient to model hundreds of millions of years of single celled organisms on earth, or whether some anonymous “bacterial species” is an appropriate representative of the species that originally acquired flagella. I won’t even worry about whether intelligent design actually offers an “explanation” at all (but see here for my sentiments on that question: no prize for guessing that my answer is “no!”).
In his suggested thought experiment Behe identified just one treatment condition: “bacteria lacking a flagellum under some selective pressure, for mobility, say”. If after some generations the bacteria have acquired a flagellum, then he says his claims would be disproven. But real experiments have control conditions to allow ruling out confounding variables. Behe’s thought experiment identifies no controls. Are any controls possible?
First, for the record recall that Behe tells us that ID does not require that we have knowledge of a designer. Again from his testimony under oath:
Q. Now does the conclusion that something was designed, does that require knowledge of a designer?
A. No, it doesn’t. And if you can advance to the next slide. I discussed that in Darwin’s Black Box in Chapter 9, the chapter entitled Intelligent Design. Let me quote from it.
Quote: The conclusion that something was designed can be made quite independently of knowledge of the designer. As a matter of procedure, the design must first be apprehended before there can be any further question about the designer. The inference to design can be held with all the firmness that is possible in this world, without knowing anything about the designer. Close quote.
OK, so we know nothing of the designer(s) or its(their) intentions, knowledge, skills and abilities. We don’t know how designers manufacture their designs in matter and energy, when they do (did?) it, whether they’re still around tinkering with stuff, nothing.
Now consider the possible outcomes of Behe’s thought “experiment”. It could produce one of two results: bacteria with flagella appear after, say, 10,000 generations, or they don’t.
Suppose first that they do, that bacteria with flagella start swimming around in the culture. Does that mean that evolution works and ID is “disproven”? Not at all. After all, since we know nothing about the skill set and intentions of the putative designer(s), it’s possible that the designer(s) somehow ‘watched’ our culture, and sometime during the course of the generations ‘reached’ in and poofed a flagellum into existence on one of the bacteria. (We will assume there are no smoke detectors in the room.) Thereafter selection takes over and by the end of the study the culture is full of the little buggers merrily swimming around. So the appearance of bacteria with flagella doesn’t allow us to discriminate between evolution and ID.
On the other hand, suppose that the bacteria don’t have flagella at the end of the study. Does that mean evolution is incapable of producing a flagellum and we must therefore infer intelligent design? Nope, not at all. After all, since we know nothing about the skill set and intentions of the designer(s), it’s possible that every time a bacterium with a nascent flagellum appeared in the culture, a designer ‘reached in’ and snipped off the budding flagellum. Why would a designer do that? I have no idea – simple perverseness, perhaps. Some of nature’s ‘designs’ display a definite bent toward perversity. But since we know nothing of the designer(s), who’s to say it couldn’t have happened? Once again, the negative outcome doesn’t allow us to discriminate between evolution and ID.
Moreover, there is no possible control condition that could settle the matter. I know of no designer “shielding” that would protect the experiment from interference, no Faraday cage that would keep the designer’s meddling influence out. Since in Behe’s (and Dembski’s) version of ID the designing agency is wholly unconstrained, there is no assurance of any protection against its potential meddling in our experiments.
The point is painfully simple: absent any constraints on what the designer(s) can or will do, there is no conceivable control condition that could make the discrimination we need, no condition that could disprove its(their) actions in anything resembling Behe’s “thought experiment”. I’ve judged middle school science fairs where the students would know that better than Behe apparently does. Behe’s claim of the experimental refutability of ID, made under oath, is specious. He once again demonstrates that he has abandoned science for mysticism, trading probity for propaganda.