If you’ve spent time with aged loved ones afflicted by senile dementia, this will ring a bell. You pay a visit to your old Uncle Ben and in the course of chatting, he comes out with an adamant statement of fact that’s clearly in error. Gently, you may try to correct him. But five minutes later, he’s forgotten what you said and makes the identical statement, more forcefully than before. You try again but, another five minutes later, you realize the capacity for short-term memory is just no longer there.

In interactions with some of our most adamant critics from the online Darwin brigade, it’s a lot like that. Well suited to the defense of an antique of 19th-century materialism, there’s a certain Darwinian dementia that keeps our interlocutors from assimilating evidence and arguments that go against their views. Some of the responses to Stephen Meyer’s new book, Darwin’s Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design, will illustrate.

It goes like this: They make a claim and you answer them. But shortly after, they are coming at you again with the identical claim, more belligerently than before, as if you’d said nothing at all. Either there’s been a genuine memory dump, or they never really heard you, or they did hear and retained what you said, but choose now to act as if they didn’t.

Take the matter of the 2003 paper by Long et al. that has served as a rallying cry for Darwinists, supposedly demonstrating, by reviewing many earlier studies, how novel genetic information arises through unguided Darwinian processes. The Long paper, which originally appeared in Nature Reviews Genetics, featured prominently in the Kitzmiller trial and decision, and our old friend Nick Matzke has been flogging it for years.

You may recall Matzke’s review of Darwin’s Doubt published at the group blog Panda’s Thumb. This is the one where he supposedly read Meyer’s book the day of its publication and immediately composed a 9,400+ word “review” all in under 24 hours. See Casey Luskin’s analysis of this feat. In Chapter 11 of the (lengthy) book that Matzke purported to read and review in that time, Meyer elaborately, devastatingly debunks the relevance and significance of the Long paper. Meyer cites Matzke by name in Chapter 11, and rebuts his specific arguments regarding Long et al. If you know Matzke as we do, you would expect him to try to bring the hammer down in reply.

Matzke in his response does indeed build up to Meyer’s Chapter 11 — he must know it’s important. But when it comes, it’s a feather’s blow, amounting to little more than a few bullet points, a spray of snarky insults, yet another assertion that Long et al. have it all figured out, and a shrug: “Anyway, most of this has been rebutted elsewhere on [Panda’s Thumb], and there is little point in doing it again.” The tone is so superior and obnoxious that the careless reader might come away with the mistaken idea that Matzke has replied to Meyer.

But he hasn’t. It’s Uncle Ben, hopping back onto the rumbling freight car of his previous line of thought, undeterred by attempts to set him straight on the facts. “So as I was saying,” intones old Ben, paraphrasing Matzke, “all this intelligent design nonsense was refuted way back in 2003 by Dr. Long, and Stephen Meyer never said a word worth repeating in answer to him.”

At least Nick Matzke acknowledges that something has been said — though, notwithstanding his high-speed reading of Darwin’s Doubt, what exactly it was that was said seems mostly to have fallen victim to a memory reset. You can engage geologist Donald Prothero on a subject — in his case, the duration of the Cambrian explosion — only to realize that nothing at all you told him has stuck in his memory. It is truly as if you never opened your mouth.

In Darwin’s Doubt, Meyer recounts a debate held in 2009, pitting him against Dr. Prothero, where Prothero contended that the Cambrian “explosion” was no explosion at all since it covered a period some 80 million years in length. That’s a lot longer than the 5 million years normally cited by Meyer and others.

In the book, Stephen Meyer patiently explains, as he did at the debate, that the figure of 80 million years is arrived at by sleight of hand, a definitional trick. As with Matzke, he cites Prothero’s own arguments:

As I was listening to [Prothero’s] opening statement, I consulted his textbook to see how he had derived his 80-million-year figure. Sure enough, he had included in the Cambrian explosion three separate pulses of new innovation or diversification, including the origin of a group of late Precambrian organisms called the Ediacaran or Vendian fauna. He also included not only the origin of the animal body plans in the lower Cambrian, but also the subsequent minor diversification (variations on those basic architectural themes) that occurred in the upper Cambrian. He included, for example, not just the appearance of the first trilobites, which occurred suddenly in the lower Cambrian, but also the origin of a variety of different trilobite species later from the upper Cambrian.

In my response to Prothero, I noted that he was, of course, free to redefine the term “Cambrian explosion” any way he liked, but that by using the term to describe several separate explosions (of different kinds), he had done nothing to diminish the difficulty of explaining the origin of the first explosive appearance of the Cambrian animals with their unique body plans and complex anatomical features. Beyond this, … the Vendian organisms may not have been animals at all, and they bear little resemblance to any of the animals that arise in the Cambrian.

See Meyer’s pp. 72-73.

Yet in Prothero’s comments on Darwin’s Doubt, he bluntly reverts to the 80-million-year figure, as if Meyer had said nothing at all: “[W]e now know that the ‘explosion’ now takes place over an 80 m.y. time framework. Paleontologists are gradually abandoning the misleading and outdated term ‘Cambrian explosion’ for a more accurate one, ‘Cambrian slow fuse’ or ‘Cambrian diversification.'” The latter claim is also majorly deceiving: see Casey Luskin’s post, “How ‘Sudden’ Was the Cambrian Explosion?“

Prothero also complains that, “[Meyer] wastes a full chapter on the empty concept of ‘information’ as the ID creationists define it,” as if he has forgotten that scientists quite apart from ID advocates have been thinking about the concept of biological information since 1953 when Watson and Crick sparked the realization that storing such information is exactly what DNA does. Meyer explains further in Signature in the Cell, but that too has been purged from the mind of Donald Prothero.

Look, obviously I’m not saying these guys suffer from a medical condition resulting in repeated cleansings of what an ordinary scholar specializing in a relevant field ought to be able to retain in his mind, especially given frequent reminders.

All of us, to some degree, are selective in the data we choose to assimilate, especially when we’re challenged on points of personal significance to us. This is how people maintain their most rigid, fixed ideas against all evidence to the contrary. With Darwinists, what stands out is the combination of arrogance with the failure to register what your opponents have said. As a tactical matter, it sure is convenient for them.