Daniel Dennett is among the foremost writers on the philosophical issues surrounding evolution. Indeed, I consider him the greatest philosopher alive. Among his books are Darwin’s Dangerous Idea, Consciousness Explained,</i> and Freedom Evolves.</i> He’s attacked creationism and its surrounding notions time and time again. But–gasp!–he’s admitted that Intelligent Design makes sense!
No, not really.
Robert Wright argues that evolution reveals a direction, and that this direction indicates that there is a Designer Who has run the evolutionary process. He claims that Dennett “recently declared that life on earth shows signs of having a higher purpose,” during an interview with Wright. According to Wright, “Dennett didn’t volunteer this opinion enthusiastically, or for that matter volunteer it at all. He conceded it in the course of a dialogue with me–and extracting the concession was a little like pulling teeth.”
Let’s pause here a moment. Suppose that Wright is telling the entire truth–Dennett actually said, during an interview, that life shows signs of a higher purpose, and that he did so only after rigorous interrogation by Wright. If that is true, it does not support Wright’s position. We are talking about a philosopher who has spent decades criticizing the notions of “purpose in evolution” in the most vocal, public, eloquent, unequivocal way. For a person who is this thoroughly committed to a proposition to break down under intense “tooth pulling” inquiry is far more likely to mean that the person misspoke, was misunderstood, was misrepresented by the interrogator, or finally broke under the strain of the interrogation and said anything to stop the psychological pressure. We know from criminal law that people will confess to crimes they did not commit, even when the death penalty is a certain consequence, if they are pressured enough. The fact that Dennett only “condeded” the point after “tooth pulling” means one of three things:
1) That Dennett has long been engaged in a lie, or in some way has dishonestly withheld the true opinion about the alleged direction of evolution, or
2) That Dennett misspoke, was misunderstood, or broke under the strain of interrogation, or was misrepresented, or
3) That Dennett experienced a revelation of the errors of his ways.
Wright, of course, characterizes the event as number 3. I think number 2 is by far the likeliest explanation, just off hand, but let’s turn to the evidence. Wright provides us with a clip from his interview here. This “interview” actually consists of a long speech by Wright, interspersed with some sentences and “rights” from Dennett. Finally, the following incident occurs–keep in mind that at this point, Wright has spoken for a solid minute:<blockquote>Wright: …you said, you said tons of organisms dying childless, right, and yet you agree that they were designed by natural selection to–
Dennett: To propagate themselves.
Wright: –the fact that some of them don’t do it doesn’t rule out that possibility. Secondly, the fact that lineages go extinct, well, that’s true in epigenesis as well. If you look at the cells that were–
Wright: –that you started out with, tons of them go extinct, and what goes on inside your body is more like a process of natural selection than–
Dennett: Oh, absolutely.
Wright: –than a lot of people realize. And one thing it has in common with natural selection is that although certain properties were very likely–I was very likely to wind up with eyesight–with eyeballs–um, it wasn’t at all inevitable which of my stem cells would be the grandfather of the linkeage that led to the eyesight. That’s also true of natural selection. So, I’m using it to the extent, I mean, I think we’ve agreed that observing, what is it, ontogeny, I guess is the term, or–you know, development of an organism–
Dennett: Mm hmm.
Wright: –that it has its direction, its movement toward functionality by design, and that’s in fact the hallmark of design–
Dennett: Mm hmm.
Wright: To the extent that natural, that evolution on this planet turned out to have comparable properties, that would work, at least, to some extent, in favor of the hypothesis of design.
Dennett: Mmmm. [Makes “well, I guess, sorta” facial expression; pauses] Uh–
Wright: To some extent. To any extent.
Dennett: Yeah, I guess.
Wright: Okay! I’ll declare victory.</b></blockquote>
Does this sound like option 3 to you? In philosophy as in all other scholarly pursuits, conversation is the least likely to lead to an important statement on a subject. Conversation is not peer reviewed, it’s not very carefully weighed before it’s uttered; people frequently misspeak, or concede points they don’t very clearly understand. Yet Wright is willing to declare on the basis of this statement alone, despite the nine or ten books that Dennett has published, that Dennett believes that evolution has a direction that upholds the concept of a conscious Designer.
This sort of “gotcha” argument is, to say the least, childish. When I was a kid, I would sometimes get in arguments on the playground, and perhaps I would misspeak–I would say the ball belonged to Rob instead of Tom–whereupon Rob’s friends would snatch my error as if it were some sort of subconscious confession of the truth, rather than a simple misstatement or error. What Wright has done here is similar. Hammering Dennett with terms like “design” and so forth, he has extracted from Dennett the most lukewarm of responses (“Yeah, I guess”) and takes the lukewarmness as evidence that Dennett is either scared of being caught or is embarrassed at how wrong his career has been all this time. At the least, Wright’s device here is the sort of exaggeration which makes for children’s playground conversation, not for science.
I could leave it there, and say that I gotcha! to Wright. But let’s look at what is really being said here–let’s try to understand, rather than counting coup. Wright is attempting a sophisticated analogy here: the cells in the body are “designed” for the purpose of, say, becoming eye cells or becoming brain cells. Some of them don’t make it, but that doesn’t disprove the fact that they were “designed.” Likewise, animals are “designed” for their environments, and the fact that some of them die off doesn’t disprove the idea that they were “designed.”<blockquote>A single egg cell replicates itself, and the offspring cells in turn replicate themselves, and so on. Eventually the resulting lineages of cells start exhibiting distinctive specialties; there are muscle cells that beget muscle cells, brain cells that beget brain cells. If [William] Paley were around today to watch videos of this process he would say: Wow!–Look at how exquisitely directional this process is; the system grows in size and in functional differentiation until it becomes this large, complex, functionally integrated system: muscles, brains, lungs, etc. This directionality is evidence of design! As it happens, you can describe the history of evolution on this planet in a way that closely parallels this description of an organism’s life cycle.</blockquote>
Wright claims to have convinced Dennett of this–in reality, he has at best suckered him into signing this without reading it. But the problem is that it wildly equivocates on the word “designed.” Dennett has never denied that biological processes reveal what he calls “design.” What he denies is that this evidence is evidence of a Designer. Evolution “designs” organisms through the process of natural selection. This terminology, Dennett has repeatedly said, is to be taken as shorthand. The “direction” of the cells in forming the human body have been “designed,” in the sense that the DNA has come to code for these things over time, because that DNA which didn’t code for these things, tended not to reproduce itself. DNA which didn’t code for eyeballs resulted in blind creatures which had less opportunity to thrive and reproduce than did creatures with eyes. There is a “direction” to the development of the eye just as a river has a “direction,” but not because Someone made it flow in that direction. Rather, it’s simply because natural processes resulted in its flowing in that direction. That’s what Dennett believes, and to discuss the term “design” with Dennett while ignoring the fact that he has written so extensively on this meaning of the word is misleading.
Now, add to that the fact that Wright was asking whether “to any extent,” if fact X happened, it would support theory Y. A philosopher can discuss these things without any connection to the reality of the case. He has asked Dennett to assume that “you can describe the history of evolution in this planet in a way that closely parallels this description of an organism’s life cycle,” and then asks if that fact would lend credence to the theory of the existence of a Designer. To that, Dennett answers with the most equivocal support. This is tantamount to asking, suppose that Columbian drug lords were out for O.J. Simpson; if that were true, would it support, to any extent, the argument that they killed Nicole Brown Simpson? The answer to any honest person is yes–but then, an honest person would not then conclude from this “gotcha” style concession that Simpson was therefore innocent. There are two problems with any such argument: first, it rests on a disprovable observation (do Colubmian drug lords really have it out for O.J.; does the world resemble the physical development of an organism in the relevant ways?) so this may undermine the claim if disproven; second, even if X would lend credence to theory Y, it could also lend credence to theory Z. Suppose Bill thinks that the moon is made of cheese. He might say to Dennett, “to the extent that the moon is the same color as cheese, would that lend credence to my theory?” Dennett would, of course, answer yes.
Wright has wrenched the sorriest sort of pseudo-admission out of Dennett, and uses it to proclaim that “there is at least some evidence that natural selection is a product of design.” (Which is silly, of course, since the very existence of natural selection constistutes “at least some” evidence that natural selection is a product of design.) This is wrong. At the very end of the full interview, Dennett says that Wright is defending the indefensible, and that “by my lights I see you going along just beautifully, and then–fft!–you veer off….where did that swerve come from?” Doesn’t exactly sound like a conversion to me.
Update 2: Prof. Dennett has forwarded me an email which he wrote to Wright, which he gave Andrew Sullivan permission to publish, so I assume that means I can publish it, too:<blockquote>OK. Bob, I just reviewed the video clip, and here is what you say, and what I say: Wright: “To the extent that . . . evolution on this planet turned out to have comparable properties [as embryogenesis, development, epigenesis], that would work at least to some extent, to any extent, in favor of the hypothesis…”
DCD: “Yeah, I guess…” (and then you cut me off and ‘declare victory.’)
But all I am granting in this acquiescence is that if evolution exhibited the properties that embryogenesis exhibits (which it doesn’t, as I’ve kept insisting) this would work to some extent in favor of your purpose hypothesis. That is, embryogenesis is not just in itself an “evolutionary” process in that there is massive excess generation pruned by cell death, etc., but it is also a designed evolutionary process–the very process has itself evolved by natural selection. But there is no evidence that the same is true of natural selection viewed from the widest perspective. As I have argued for years. So all I am agreeing to here is the hypothetical, and I’ve rejected the antecedent of that hypothetical all along. You draw attention to an interesting avenue of argument that has not been particularly well explored so far as I know, but I don’t think it is a winner. It reminds me of the Gaia hypothesis. If life on our planet really were designed to be in homeostatic, self-sustaining balance, then the Gaia freaks would be on to something, but there is no reason to believe this.
So you forget that you’d posed a hypothetical to me, and run off with my answer without giving me a chance to elaborate. This after a most concerted effort to get me to agree with you that I steadfastly resist to the point of tedium! To my ear, this is what happens:
“Wright. blahblah, Dennett, NO. Wright, blahblahblah. Dennett, No again. Wright, blahblahblahblahblah, Dennett STILL NO. Wright, But won’t you agree that IF blahblahblahblahblah, Dennett, Well, yes, if all you mean is . . . . Wright, TaDAA! Dennett agrees with me!”
Not good ground for your rather inflammatory interpretation–would you agree? I am not impressed.</b></blockquote>
Update 3: More at Protein Wisdom.
Update 4: More at Majkthise.