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June 1, 2007

See, Here's the Thing About Evolutionary Argumentation

Justin Katz

It is not my intention, herewith, to offer a supporting addendum to Sam Brownback's New York Times piece about evolution, although I think his gist is surpassingly reasonable. Rather, in reading the discussion of that piece in the Corner — which I'm sure is, or might as well be, playing out in various venues across the country — it seems to me that an important point is being missed.

To begin, John Derbyshire (amidst a collection of phrases that followers of the debate will recognize as puffed feathers) offers the following explanation of his scientist response to Brownback's scientific understanding (all emphases in original):

The problem with this position is, that you need to observe — or at least, darn it, hypothesize — some mechanism that stops the micro before it goes macro. (Not to mention that you have to posit some mechanism, other than macro-evolution, for the origin of species... But leave that aside for the moment.)

Take, for example, allopatric ("different homeland") speciation. You have a population of living, sexually-reproducing organisms, all belonging to the same species (i.e. able to mate with each other). You observe variations within the population. You further observe, watching across several generations, that some variations (red hair, schizophrenia) are heritable in whole or part, some (appendectomy scars) are not heritable at all.

Now you divide your population in two: Population A and Population B. You separate them geographically. (Hence "diferent homelands.") You observe that A and B have different "menus" of heritable variation (A has more redheads, B more schizophrenics). You further observe that A's and B's environments are different — A's is hot and dry, B's cool and wet.

You sit back and observe for a few thousand generations. Yep, microevolution goes on. A changes, B changes. Because they started out with different menus of heritable variations, and because environmental pressures in the two places are different, they change differently. They diverge. A thousand generations on, the two populations look and behave differently from each other. Ten thousand generations on, they look and behave way differently. Orthodox biology ("Darwinism") says that eventually they will be so different, they can no longer interbreed. Speciation will have occurred. A and B are now two species.

Under Brownbackian evolution — micro yes, macro no — this can't happen. They can't go on diverging. They can only get so different, no more. The divergence must slow down and stop. But... what stops it? What's the mechanism?

The accumulating Corner posts (here, here, here, here, here, and here) get all the way to a philosopher's suggestion that "unless we can make a convincing case that the choice is not between relativism or dogmatism, more and more people will reject the former and embrace the latter," but at no point does anybody address what the average person will find objectionable (even if unarticulatedly so) in Derbyshire's explanation. How is it — why is it — that hot/dry versus cool/wet conditions ought to be expected to transform hair color and psychosis into biological differences so vast that sperm and egg will no longer function together? An equatorial African human being can still, as far as I know, mate with an Eskimo, and yet chimpanzees would be schtupped to no avail.

Now, I'm absolutely positive that there's a very clever and ever ready response that I haven't the time, just now, to read with the merited attention, but my experience leads me to predict that the back and forth would — not unlike the hypothesis of "micro yes, macro no" — merely change the terms of the debate, without substantially altering the beliefs of those involved. I'm not saying that those beliefs are stubbornly unreachable, but taking the discussion to the boundaries of my comprehension, I've always found the assumption (e.g.) that it's just so darn logical for environmental factors to change organisms in more and more dramatic ways to dominate the details. Meaning that the details appear proposed mainly to illustrate how the assumption could be true.

To some degree, this is just how science must function. "So far, x has provided predictive information with respect to question y, and if we were able to prove that it functions also as X, then we could explain Y, or even Z." Perhaps what's so frustrating about the whole dispute is that rational religion functions in much the same way, just with a broader class of considerations. "Yes, but the way in which I understand 7 has a certain relevance to question y, and given millennia of compelling thought about numbers (and your certainty that X proves the whole effort to have been misdirected), I'm going to insist that there is something of 2 in Z, regardless of the alphabet." I'm not one to disclaim science's ability to explain the world in which we live, but to the extent that it smuggles in a philosophical materialism, one must risk accusations of creationism to state with certainty, as Brownback does, that "man was not an accident and reflects an image and likeness unique in the created order." Simply put, there is a form of comprehension distinct from scientific thought without which no understanding of the world is complete.

Julian Baggini, the aforementioned philosopher, writes the following in the piece to which Derbyshire and Jonah Goldberg tread in their conversation:

Richard Rorty, for example, argues against Truth brilliantly, and it is far from clear that he is simply wrong. The problem is that he does not concede as unequivocally as he should that in practice his theories usually leave the world more or less as it is. Rorty believes as much as anyone else that the Holocaust happened more or less as described in history books, he just refuses to use an allegedly outmoded vocabulary of truth to say so. It is not quite fair to call his refusal in such contexts a pose, but it is certainly not quite what it seems.

Ironically, like many left-leaning intellectuals, Rorty thinks that denying objectivity and truth is politically important, as a way of liberating people from the ways of seeing the world promoted as the Truth by the powerful. However, it turns out that Rorty and his ilk seriously misjudged what happens if intellectuals deny truth stridently and frequently enough. Far from making liberal openness more attractive, such denials actually make it appear empty, repugnant and weak compared to the crystalline clarity and certainty of dogma.

Stepping back from the glint of ivory, one can see that the masses do not, in their ignorance, cling to dogma because the academics have left them no middle ground. Those academics aren't making liberal openness seem "empty, repugnant and weak" — language that inherently buys into the academics' elevation of power as the driving force of all human behavior — but that they make it seem wrong, or at least so unbelievable that those who profess it don't actually behave as if it is true.

Such declarations, for all their dogmatic certainty, merely resonate all the more loudly as the bunk that they are. The more monolithic the proclamation, the more apparent it is that the intellectuals, at some point en route to their PhDs, underwent an amputation of the intrinsic human sense that that which has been created likely has a creator, that the miraculous appearance of deliberateness, joined with a longing for and feeling of purpose, is at least suggestive of deliberate purposefulness.

Too often, the purpose of denying truth appears to be the otherwise unjustified allowance of preferences that "the world promoted as the Truth by the powerful" would treat as suspect. Too often the attacks on certainty give the impression of a strategy to promote the power of those who specialize in obscurity. "You're deluded," they say, "in thinking that there's any objective truth, so you should indulge my various urges and subscribe to my political solution to the world's ills, all perpetuating a system that allows me to make a comfortable living explaining why boogers are actually lint when removed from my naval, while you toil in the fields." They are clever enough to prance around any old Truth that might be mentioned, and they insist that the rest of us must be able to reassert those Truths in a way acceptable to them. Otherwise, we are merely retreating to the comfort of certainty, and if we begin to think that a society that devotes its resources to meaningless nonsense could use some reworking, we're reactionary barbarians lashing out at our own insecurities.

Without drawing too close of a comparison between academics defending a philosophy and scientists defending a theory, this leads us back to suspicion of evolution. I don't think it necessarily indicates a "new position" to which "creationists have retreated" to wonder why the burden is on believers (who often would scoff at being called creationists) to explain why humidity wouldn't eventually make a sperm and an egg incompatible. Derbyshire does a bit of weaseling of his own when he assumes that the unlimited capacity of heritable tendencies and "environmental pressures" to change a species is so obvious that it cannot be questioned without the development of an alternative mechanism that is science-like in its exclusion of anything that is not materialistic.

Layer on enough environmental pressures, and the environment begins to look more like an oven that a wildfire, and heritable tendencies more like ingredients than random minerals. Indeed, mutations and unique natural events begin to give the impression of stirring. Thus we arrive at Brownback's bottom line:

If belief in evolution means simply assenting to microevolution, small changes over time within a species, I am happy to say, as I have in the past, that I believe it to be true. If, on the other hand, it means assenting to an exclusively materialistic, deterministic vision of the world that holds no place for a guiding intelligence, then I reject it.

Even Goldberg argues that this sets up a "strawman... saying that if you believe in anything more than 'microevolution' you're buying into a cold, godless, materialistic universe," but that attributes more weight to Brownback's positive argument than appears to be intended. The question that he's answering is why he would raise his hand when asked whether he did not "believe in evolution." His explanation is that he believes in evolution as a natural process of relatively minor differentiation, but not (as the question is often meant to imply) as a way for all life to have developed under the indifferent eye of randomness. Anything between must be specified — although the discussion is not likely to fit in an opinion column, much less a debate — so that the believer has the opportunity to specify where the proposed pressures do not appear sufficient to change the very character of the creature and where the mechanisms have begun to give the impression of design.

Comments

This is one of the things that baffles me the most about religious objections to evolution: the very strawman you identify. Accepting the overwhelming evidence for the scientific truth of the theory of evolution in no way forces one to accept a godless, amoral world. I don't understand why a world in which life developed under the "indifferent eye of randomness" (although I, and many biologists, would dispute your use of the word "randomness") necessarily constitutes a threat to moral order.

Anyway, I find discussions that seek to differentiate between "micro" and "macro" evolution exasperating, especially claims like, "Sure, evolution can explain changes within a species, but I don't believe it can account for speciation." Speciation has been observed.

An equatorial African human being can still, as far as I know, mate with an Eskimo, and yet chimpanzees would be schtupped to no avail.... explain why humidity wouldn't eventually make a sperm and an egg incompatible

Whoah, check out the straw on that guy! The differences between the Eskimo/African case and the human/chimpanzee case are many, but the biggest ones are time and isolation. Eskimos and Africans just aren't all that isolated from one another, on a reproductive basis, on an evolutionary timescale.

I think that people of faith would be better served by relaxing their skepticism on evolution (which is more or less the equivalent of skepticism on quantum mechanics) and focus their energies on articulating why the truth of evolution constitutes and challenge to their beliefs, and on constructing defenses and arguments in the theological, not the biological, domain. The noble history of religion is found in the work of its brilliant moral thinkers who thought, believed, and prayed in the context of their historical times. This is an opportunity for religious faith to grow and expand, not to contract.

Posted by: mrh at June 1, 2007 8:40 AM

What I found troubling about Brownback’s final summarizing statement is that you could use the same logic to reject just about any branch of science…

If belief in classical mechanics means simply assenting to the fact that force equals mass times acceleration in individual cases, I am happy to say, as I have in the past, that I believe it to be true. If, on the other hand, it means assenting to an exclusively materialistic, deterministic vision of the world that holds no place for a guiding intelligence, then I reject it.
In other words, the fact that some philosophers used classical mechanics to help justify an atheistic philosophy (or maybe more properly, a deistic, God-lite one) did not mean that classic mechanics should have been rejected.

Posted by: Andrew at June 1, 2007 8:53 AM

Remember the "Big Bang" the "humanists" were promoting as "scientific fact" for the last century. Well, according to NPR's one hour 11AM program yesterday they have abandoned that for some other mumbo jumbo.
Evolution as a cosmology will also ultimately be abandoned by the "humanists" in favor of some other tautology. These are the same "experts" who bled people with leeches.
I'm sticking with Aquinas.

Posted by: Mike at June 1, 2007 8:53 AM

So Mike, are you saying you believe evolution to be false? I just want to be sure who the sloped-brow, 'Earth is 4,000 years old', drooling morons are before I wade into this conversation.

Posted by: Greg at June 1, 2007 8:58 AM

Mrh,

With his African/Eskimo example, I believe Justin was saying that John Derbyshire's argument would be stronger if he could explain the mechanism by which a new species come about, instead of simply asserting that it's inherently obvious that such a mechanism must exist.

Posted by: Andrew at June 1, 2007 9:10 AM

Andrew,

Fair enough. God knows I don't want to argue the pro-Derbyshire position so much as the pro-evolution position. While Derbyshire may not explain such a mechanism, evolutionary biologists can.

Thanks.

Posted by: mrh at June 1, 2007 12:52 PM
Whoah, check out the straw on that guy! The differences between the Eskimo/African case and the human/chimpanzee case are many, but the biggest ones are time and isolation.

I see no straw. Derbyshire suggested that "micro yes, macro no" believers must present a mechanism to stop the micro from becoming macro. Toward that end, he presented a simplified scenario of the mechanism that the believers would have to stop. I merely pointed out that I don't find the change of location and climate to be such a huge influence that even thousands of generations would change human beings' reproductive compatibility — witness the Eskimo and the chimpanzee — at least not in a way that is obvious.

It is as if I were to successfully charge my neighbors for using my lawnmower and, after the first three, I told somebody who cautioned me about making too much of that success that he had to come up with a mechanism that would stop my mower lending from becoming a multibillion-dollar business. He'd be correct to suggest that I don't have that many neighbors. (Of course, I might be able to make a business of it, but then I'd have to come up with a new, more expansive mechanism.)

Posted by: Justin Katz at June 1, 2007 5:22 PM

So Mike, are you saying you believe evolution to be false? I just want to be sure who the sloped-brow, 'Earth is 4,000 years old', drooling morons are before I wade into this conversation.
XX
Did you grow up believing in the absolute certainty of the "Big Bang" theory the "experts" just discarded like old fish?
Evolution as a cosmology fails since you run out of "lower life forms" and by another "law of science" spontaneus combustion is not possible. I find more wisdom in aquinas than in all the atheists of the last century-Hitler, Stalin, Mao, etc.

Posted by: Mike at June 1, 2007 8:00 PM

what does atheism have to do with any of this? In fact, why does evolution or the big bang disprove god? God forbid, mike anyone believe in science and god at the same time.

If we want to talk strawmen lets talk about you bringing up Hitler, Mao, and Stalin in a debate about evolution. Ever heard of godwin's law?

Posted by: George at June 1, 2007 11:02 PM

Justin, I'm more than willing to concede that Derbyshire is unconvincing. That's not a point scored against evolution, though.

If the thrust of your post is that Derbyshire is a crappy argumentarian, I'll happily retire to the sidelines -- I've got no skin in the game. If, however, you're trying to argue that "macro-evolution" can't account for speciation, then I think you're in trouble on the evidence.

Posted by: mrh at June 2, 2007 12:05 PM

Did you grow up believing in the absolute certainty of the "Big Bang" theory the "experts" just discarded like old fish?

Greg can argue his own side, Mike, but "absolute certainly" rarely enters into science.

Posted by: mrh at June 2, 2007 12:07 PM

I tend to believe it's far more likely that two planar dimensions bumped into each other causing a massive explosion of matter and created a new planar dimension than it is that some omnipotent deity got bored one day and said "Let there be light" and there was and it was good.

And, if your God exists, he's one helluva crappy deity indeed. At least the Native American Gods would make it rain when they prayed to them. What has YOUR God done lately? If there was ever a time for him to give us a hint that he exists, I would think now might be a good time.

Posted by: Greg at June 2, 2007 2:03 PM

Greg,

I don't consider your comment worthy of reply. For one thing, I think you're too smart to mean it seriously. For another, I'd hate to think that you take me for such an imbecile as to assent to mockery by giving serious response.

Posted by: Justin Katz at June 4, 2007 7:49 AM

MRH,

I'm not arguing anything as spectacular as that "'macro-evolution' can't account for speciation." I'm merely suggesting that, a bit more broadly than contra Derbyshire, that scepticism that microevolutionary mechanisms account for the vast variety of life is not wholly unreasonable. Look, even, at your link above about instances of speciation: There are multiple interpretations of apecies, some of which, in context of this debate, read like "close enough."

Now, if you want to throw in notions such as "fortunate monsters" (or whatever the coinage is) and rapid mutations, well then, I'd say I've a little more ground to whisper about the hand of God.

Posted by: Justin Katz at June 4, 2007 7:52 AM

Justin,

Well that's (one of the many places) where we disagree. Skepticism on nearly any subject is never wholly unreasonable. I just think your skepticism on evolution should be tempered a bit. Evolution looks, to all the available evidence, to be the answer to the question "where do all of these creatures come from?"

I just don't understand why that answer is such a threat to religious folks.

Posted by: mrh at June 4, 2007 12:43 PM

I'm not sure what, specifically, you mean by "that's (one of the many places)," but I'd suggest that you're drifting in the Derbyshire direction, wherein religious folks' noticing of various different evolutionary mechanisms and categories sparks vehement assertions about the gospel truth of evolution, while your use of that term in the argument requires that one take it as a whole — the mere premise of it, of its non-directed nature.

Admittedly, it's been a while since I looked into the specifics of the science, but as I recall, the evidence requires more than just the gradual and (given understanding of the environment) logical progression of species in different directions, which is what I sought to encapsulate in the reference to fortunate mutations.

As for the reactions of "religious folks," your lack of comprehension clearly involves a lapse of mind when it comes to the historical context of the debate. It also ignores the other side, which — as Greg was happy to illustrate — incorporates a stark anti-religious zeal. How could religious citizens not see it as a threat that evolution provides (most predominantly) a wedge for the (usually tacit) preaching of Greg's gospel to to their students?

Posted by: Justin Katz at June 4, 2007 6:54 PM

I'm not asserting the "gospel truth" of evolution. Such an idea would be a category error, as evolution is a scientific theory, not a religious precept.

Perhaps I misunderstood you. You seem to be not "noticing ... various different evolutionary mechanisms" but rather claiming that evolution can't account for speciation. If this isn't your claim, then I don't know quite what it is.

I don't think your recollection ("the evidence requires more than just the gradual and (given understanding of the environment) logical progression of species in different directions" jibes with the current scientific consensus.

My lack of comprehension doesn't involve a lapse of mind, thank you very much. Yes, there are some scientists (P.Z Myers? Richard Dawkins?) who have an anti-religious zeal. Why in the world does that have any bearing on the truth or falsehood of evolution?

If some anti-religious zealots want to use evolution as a wedge to teach atheism, well, perhaps, shame on them. Evolution tells us nothing about the existence of God. Nothing! But to resist the teaching of evolution, even though it's true, because of Dawkins, Myers, and Greg is ridiculous.

There's a very interesting debate to be had about religion, atheism, and education, but the truth of evolution shouldn't be a part of that debate.

Posted by: mrh at June 5, 2007 1:18 PM

Matt,

I do not know what it is I'm failing to communicate, or perhaps you keep adjusting what I say in keeping with some incorrect image that you have of me. You said:

I just don't understand why that answer is such a threat to religious folks.

I merely offered an assessment of what religious folks find threatening, based on the history of the debate, and it appears that you've changed the terms of the question:

Why in the world does that have any bearing on the truth or falsehood of evolution?

I wasn't making a point one way or the other on that. Perhaps based on a leap on your part — from my argument that it is reasonable to be skeptical of some of the broader evolutionary claims to an assumption that such skepticism is motivated mainly by an urge to avoid a threat — I was treating that part of my response as something new in the discussion.

Returning to the other component of my response, I've looked it up, and the term for which I was grasping was "hopeful monsters," which is often taken to be a more colorful synonym for punctuated equilibrium, an attempt to explain the absence of a fossil record of macroevolution. Incorporating this into my reply to Derbyshire, his evolutionary scenario would have to be adjusted to include a step in which a species moves elsewhere and evolves greatly over a few generations. That is where, for example, the skepticism and the whispering about God's handiwork come in.

Posted by: Justin Katz at June 5, 2007 8:21 PM

absence of a fossil record of macroevolution

But there is no such such absence; on the contrary, there is a fossil record.

Anyway, if the threat to believers is just that some scientists are rude, then I think we're all going to be OK.

Posted by: mrh at June 5, 2007 9:09 PM

Perhaps I overstated and should have put the word "some" in there, but I was merely illustrating a more general point. I'm not among those religious folks who aren't willing to accept the probability that God works through evolution, so I'd be as apt to argue with such people that taking something like punctuated equilibrium to be evidence of His handiwork means that one might as well take all of evolutionary theory to be such, as well, as I am to argue with materialists that they've no justification for writing God out of the universe based on evolution. My point is that the simplified story of evolution is of small changes over very, very long time spans, but it remains necessary (as I note even in your source) to admit that sometimes changes occur rapidly. It is within this more complicated picture that those across the spectrum of preferences for the interrelation of science and religion can begin to understand each other's assumptions and priorities and, to some degree, manage a cordial compromise.

Posted by: Justin Katz at June 5, 2007 10:07 PM

I'll just point out in closing that punctuated equilibrium is now more or less the consensus opinion among evolutionary biologists (there aren't really any "classical Darwinists" any more), and that PE predicts (and the fossil record shows) change that is "rapid" only on the geological timescale.

Precision as to the mechanism by which evolution brings about speciation is important in a conversation about the truth of evolution: to be convincing, we have to present the best set of facts we can. I still maintain that a proper understanding of evolution's mechanism's neither precludes nor requires the existence of God (and I think you agree).

I'm a big proponent of cordiality, and one of the best features, for me, of our occasional conversations is the opportunity to explicate my underlying assumptions and to try to understand yours.

Posted by: mrh at June 6, 2007 7:58 AM