Sunday, June 14, 2009

The Self-Weaving Tapestry

Evolutionary geneticist Jerry A. Coyne's recently published Why Evolution Is True is a lucidly written enumeration of the mountain of scientific evidence that says Darwin was right: life, once it began on this planet, evolved on the 4.54-billion-year-old earth over the last (as we now know, but Darwin didn't) about 3.5 billion years.

In that span, the first life forms — single-cell prokaryotes: bacteria — evolved into millions upon millions of multicellular species, the huge majority of them having debuted, strutted and fretted their hour upon the stage, and long since gone extinct.

Of this "tree of life" our species is one branch — or, better put, one twig.

Furthermore, the main engine of evolution is natural selection, which sifts the heritable variations that typically occurs in any population of living organisms and rewards those that most predispose their organisms to survive and reproduce.

Natural selection can accumulate the happenstance copying errors that occur quite frequently in the molecular basis for heredity, DNA, eliminating those that produce maladaptive traits while propagating those that make their bearers fitter to survive and reproduce. Under certain circumstances — typically very gradually — the accumulation of adaptive, fitness-promoting "mutations" (as we call changes in the sources of heritable variation today) produce a brand new species.

Darwin figured out the conceptual basis for evolution by natural selection in an age before we knew anything of genes and DNA, or how to use radioactive clocks to see how old the earth is. He first published his ideas, along with a flood of arguments and examples demonstrating their veracity, in 1859 in On the Origin of Species.

Though what we today call genetics and molecular biology were as yet a closed book to him, he knew about the ways living kinds distribute themselves around the world in clumps that reveal common descent, about the evidence of modern species' common ancestors in the fossil record, about how the traditional taxonomic classification of living forms mirrors evolutionary descent, and about the way breeders of animals and plants recapitulate natural selection with artificial selection.

Thus did he demonstrate that the suspicions of his scientific peers and predecessors were true: evolution happened. His major new contribution was the idea of natural selection, not the idea of evolution itself. Yet for decades after Origin appeared, natural selection was anything but an accepted doctrine. Many of Darwin's contemporaries and immediate heirs resisted the idea that such a blind, slow watchmaker as natural selection could possibly account for life's stunning diversity.

Whatever the degree of resistance to natural selection as a scientific idea, Darwin showed that it had to be at least one of the engines of evolutionary change — he allowed for other engines as possible co-contributors; evolutionists today typically focus mainly on selection — because natural selection couldn't be prevented from taking the vagaries of heritable variation in directions consistent with the ongoing adaptation of organisms to their (usually, perilous) environments.

Though Darwin himself raised the issue of selection's possibly not being strong enough to account for the origin of all species, he gave plenty of evidence that it might well be the evolution's taut mainspring ... for if selection alone doesn't account for every instance of speciation, if (as he showed) creationism doesn't explain anything at all, and if all of the other candidate mechanisms Darwin reviewed have today been discredited, then what are we left with?

True, most modern evolutionists say "genetic drift" — adaptively neutral traits that arise in populations of limited size for statistical reasons alone — powers some evolutionary change.

And a smattering of evolutionists would add "self-organization" as a further complement to natural selection: the ability of living systems, like "nonlinear dynamical systems" in general, to generate rapid and surprising increases in biological complexity by tuning themselves to an abstract regime called the "edge of chaos." Still, all evolutionists today would agree that unaided natural selection would be strong enough to power the origin of all species, in the absence of such putative aids and complements.

Even so, fully a century and a half after publication of Origin, we remain locked in a culture war over Darwin's two signal ideas, evolution and natural selection.

Today's anti-evolutionists call themselves, variously, "creationists," believers in "creation science," and proponents of "intelligent design." Increasingly, though, intelligent design's proponents disavow any religious motivation ... unlike their "Genesis creationism" and "creation science" predecessors. (My opinion: there are in the world approximately zero adherents of intelligent design who are indifferent to religion.)

Yet — and this is what I really would like to get at here — I do not think that the simplistic notion that all Darwinians are un-spiritual, or anti-spiritual, is necessarily so. Yes, some profess atheism, others agnosticism. Many label themselves "freethinkers," or "brights," or "secular humanists." And, yes, Darwinians are generally committed "materialists." But my take on that is this: There is nonetheless a kind of elevation of the spirit that their materialistic, atheistic, agnostic, freethinking bent can lend to life.

My own mental model for saying so is the late astronomer Carl Sagan, whose 1980 television series Cosmos still resonates with me; I have viewed it over and over again on videocassettes, DVDs, and even iTunes downloads.

Sagan distilled the scientific view of the universe into 13 one-hour episodes with titles like "Blues for a Red Planet" and "The Shores of the Cosmic Ocean." How, Sagan asked, did the universe begin and proceed to evolve galaxies, planets, and on one (or more) of the planets, life? Fascinating him as well was always this inquiring counterpoint to the same fugue: How did humankind's evolving penchant for "figuring it out" begin with the ancient Greeks and then evolve into modern science?

Sagan was at one and the same time a skeptic and a romantic. As a scientist, he was skeptical of those things, especially beliefs like astrology that have historically been dear to human hearts, that the scientific method cannot demonstrate the veracity of. Yet dear to his own heart was the charming notion that intelligent life exists elsewhere in our Milky Way, and that we can hope to pick up evidences of it in intercepted radio signals originating from great galactic parsecs away.

The cosmos as Carl Sagan presented it is a majestic tapestry, unimaginably huge, mostly empty, but here and there studded with complex, intricately woven outcroppings of natural law and cosmic order: our galaxy, our solar system, our planet, life on that planet.

Even more awesome is that it is a tapestry that weaves itself.

Carl Sagan described himself as an agnostic, not an atheist (see here). In a 1981 interview with U.S. Catholic, Sagan said: "I have some discomfort with both believers and with nonbelievers when their opinions are not based on facts ... If we don't know the answer, why are we under so much pressure to make up our minds, to declare our allegiance to one hypothesis or the other?"

In an interview with The Humanist magazine conducted after Sagan's death in 1997, his wife, Ann Druyan, said that neither she nor her husband believed in a traditional God or an afterlife.

True, the universe as a tapestry that weaves itself calls into question the traditional biblical God who makes us in his image and who greets us in heaven after we die.

But never mind. The secular humanist Philip Kitcher writes in his defense of evolution theory, Living with Darwin, of "the genuine possibility of comfort without supernaturalist hope":
"When the soprano soloist sings the movement Brahms added at the last moment to his German Requiem, "I will comfort you as one whom his mother comforteth" ("Ich will euch trösten, wie einen Mutter tröstet"), the promise is literally false — there is no God who will wipe the tears from our eyes — but the music itself consoles" (p. 158).

The music itself consoles. The tapestry self-weaves. Can this come to be enough, for us, to wipe away our tears at the loss of Genesis?

Tuesday, June 17, 2008

Bosom Buddies

This post is one that doesn't seem to fit into any other of my blogs, so it's going here. I'll try to give it an evolutionary spin accordingly.

My bosom buddy Nan (not her real name) told me yesterday she has recently had to have a malignant lump removed from one of her breasts. It is the first time, in the long history of benign masses which Nan has had to endure that the new spot on her mammogram has not been merely a cyst. Nan got so used to discovering benign lumps that she mistakenly delayed getting a mammogram for a lump her self-testing revealed last year ... a delay which worked eerily to her advantage this year! Because she put off her 2007 mammogram, her 2008 diagnostic came only six months after the prior one. Her cancer showed up on the more recent one, but not on the previous one, with the result that she knows she has caught this dangerous new mass very early indeed!

Nan and I are old, dear friends who have never been romantically involved with one another. Even though I am a guy, I find that I share her pain and peril, her fright and fear almost as much as I imagine any of her gal friends would do. Nan is almost like the sister I never had, and although she has two brothers, I believe she thinks of me as sort of an honorary third brother as well.

What is it about the breasts that make them as a site for cancer seem doubly problematic, vis-à-vis, say, the colon or the pancreas?

If colon or pancreatic cancer is successfully overcome, life returns to normal.

Breast cancer, though, carries with it the threat or actuality of a mastectomy. If Nan's cancer, God forbid, has spread to her lymph nodes (her diagnostic for that is still in the offing) she will probably need to have one or both breasts removed.

Now, I haven't expressly brought this possibility up with her, so I don't know for sure how she would feel about it. But I think I know how she would say she feels. She would say something like, "I'm past the age of having children and potentially breast-feeding them. Other than that, a woman's breasts are useless appendages of adipose tissue and ductwork. Good riddance to them!"

Well, since I too am past the age of fatherhood, would I feel OK with losing a testicle to malignancy — again, God forbid that the occasion should ever arise?

No, truth be told, it would be crushing to my self image to lose even one of my family jewels. And if that ever were to happen, my missing gonad would not affect in the slightest the way I look to the outside world when fully dressed. No one could tell I was "hanging" any differently than I was before.

If I were of Nan's gender and lost one or both of my breasts, though, then absent reconstructive surgery or a prosthesis I would quite simply look maimed to one and all.

There are prosthetic testes, I believe. The problem is not just how "normal" we look, though, but how normal we think we are.

Most of us lose organs — an appendix, tonsils, adenoids, etc. Our identity is not bound up with such tissue, though. Women, Nan included, have hysterectomies., and they don't seem to curl up and die, figuratively speaking, when this procedure is performed on them. Why not? I think it's because they're typically past the age when they want children, so their uterus and ovaries are no longer factors in their identity.

Testicles, on the other hand, remain bearers of a man's identity throughout his life. He thinks of them as the basis of not just his fertility but also his virility, his manliness.

Likewise, a woman's breasts seem to furnish the basis for her femininity image ... or so it seems, at least from the male perspective. The male of the species makes a symbolic link between what his testicles mean to him image-wise, and what the breasts must mean to a woman.

The question arises of whether a woman really identifies her sexual image with her breasts as much as we men believe she does.

I think yes.

Even though the breasts are but "secondary sexual characteristics" that no longer have a life-or-death biological function in this age of bottles and infant formulas, evolutionarily the mammaries of Homo sapiens, or the female version thereof, played a big role.

Or why are they so big, size-wise? Why are the nipples so prominent?

The mammary organs of our primate cousins and evolutionary forebears are small and hidden in fur. When body fur departed and hominoid creatures began to walk upright, female breasts and nipples got big for the first time. The reason? My guess is that they made it easy for male and female hominids alike to tell the difference between the sexes from afar.

Imagine you're a hominid male bonded with a certain nubile female. Your band of brothers — and sisters, and close and distant cousins — roams the savannah day by day in search of food. As you spread out on your daily forage, you and your mate don't necessarily stay side by side, but you tend to keep a jealous eye on her as you both go about your hominid business. Quite often you notice that her "personal space" is being shared by another in your band. Anything to worry about? Not as long as you can see breasts on Hominid #3!

In fact, a female who happens to be under-endowed in the boobs department is apt to find herself becoming (wrongly) the object of male tantrums of jealousy from time to time. The other females are apt to shun her out of fear of repeated nasty boyfriend incidents, all because Susan Simian looks too much like a boy. This is the kiss of death in a social species like us and all our evolutionary ancestors. So natural selection is going to get busy and start pumping up those (what will one day be) bra sizes in an understandable quest to ensure domestic tranquility.

Then, rather unexpectedly, those ballooning breasts, those mushrooming mammaries, become more than just long-distance no-reason-for-jealousy confirmers. They become cause for male arousal, since us guys like to be sure that lovely creature we are wiggling our eyebrows at from afar will turn out to be worth it, up close and personal. What better to act as signals that arousal is appropriate than those newly pneumatic boobs?

In short, evolution has given the breast socio-sexual roles that it was never, as a mere milk-producing appendage, supposed to have. And evolution has implanted those roles in our brains in ways that our culture, when it arrived on the scene, would only magnify.

So, now, when someone like my bosom buddy "Nan" is confronted with the possible need for a mastectomy, the potential loss of one or both breasts must threaten her sense of personal socio-sexual identity in ways that make little rational sense. As if the threat of dying of cancer weren't enough to have to deal with ...

Thursday, May 22, 2008

Expelled: No Intelligence Allowed

Expelled: No Intelligence Allowed — Ben Stein Launches a Science-Free Attack on Darwin is an online article by Skeptic-in-Chief Michael Shermer, an edited version of which appears as "Expelled Exposed" in the June 2008 Scientific American. The article's topic is the documentary film recently produced by actor/game-show host/financial columnist Ben Stein. The movie's title, Expelled: No Intelligence Allowed, refers to how, in Stein's view, the "theory" of intelligent design has been exorcised falsely from our science classrooms.

Intelligent design is the name given by its proponents to the idea that important body structures — wings, eyes, brains, the gene-bearing double helix of DNA itself, and even the rotary flagellum that propels many bacteria — arose, during the course of Earth biohistory, against colossal odds that were insurmountable by nature acting alone. Because the odds against such complexity arising without any help from The Man Above were so huge, the only legitimate conclusion is that there must have been an Intelligent Designer outside this world whose activity helped evolution over several otherwise impossible humps.

To Shermer, intelligent design, not Darwinian evolution, is the idea that is false. Intelligent design shouldn't be taught in American classrooms as accepted scientific theory, because it isn't. It's an attempt to use scientific language to justify religious belief.

The standard theory of evolution, Shermer and other Darwinists hold, accounts fully for wings, eyes, brains, DNA ... and bacterial flagella. There are no insurmountable humps in the history of evolution guided by natural selection alone. Over the course of more than four billion years, there was a process of slow, steady change to the various genomes carried by the DNA molecule, once nature had invented that molecule. (The origin of DNA itself — the provenance of the very first genome-bearing life form — is admittedly still uncertain.)

All life forms but the first happened as a result of that slow process which Darwin called descent with modification. Down through Earth's long life history, genetic changes called mutations were culled by natural selection, an impersonal force that weeds out changes that harm the chances to survive of the organisms that possess them.

Genetic mutations that help their possessors survive are "adaptive," in evolutionary terms. Other mutations are neutral. Yet others are so harmful they cannot persist in the genome. Some can be harmful under specific circumstances, but still persist in a genome.

Yet others make for helpful new traits (or are neutral or even mildly harmful) and are later "exapted" — rededicated — to produce different adaptive effects than they originally had (if they had any at all). The dynamics of genetic change, whether or not any one change is immediately adaptive, are sufficiently rich for eyes, wings, etc. to arise by a long, slow, step-by-step process, none of whose individual steps is all that unlikely to occur.

That's the standard outlook on Darwinian evolutionary theory to which Shermer subscribes.

Shermer, because he is a professional skeptic, was interviewed by Stein for his movie, and Shermer in his article recounts how Stein kept badgering him to justify the supposed firing of teachers for advocating intelligent design. However, according to Shermer the alleged firings over intelligent design all had other explanations — see the Expelled Exposed website. Shermer thinks Stein is thus using non-facts about recent history as a basis for non-scientific propaganda about evolutionary facts.

To Stein, though, intelligent design is a theory that makes sense. Why? Apparently, in part because (in Stein's estimation, at least) Darwinian beliefs about God's non-involvement in the creation of Earth's living species are very, very harmful to human society. Writes Shermer:

Even more disturbing than [the film's] distortions [of science] is the film's other thesis that Darwinism inexorably leads to atheism, communism, fascism, and could be blamed for the Holocaust. Despite the fact that hundreds of millions of religious believers fully accept the theory of evolution, Stein claims that we are in an ideological war between a scientific natural worldview that leads to Stalin's gulag archipelago and Nazi gas chambers, and a religious supernatural worldview that leads to freedom, justice and the American way.

Shermer goes on to say:

When will people learn that Darwinian naturalism has nothing whatsoever to do with religious supernaturalism? By the very definitions of the words it is not possible for supernatural processes to be understood by a method designed strictly for analyzing natural causes. Unless God reaches into our world through natural and detectable means, he remains wholly outside the realm of science.

That first sentence starts out differently — "When will Americans learn that evolutionary theory has nothing to do with religion ... " — in the magazine condensation of the online article. I have a bit of a problem with that latter formulation. I think there are millions of American citizens who feel Darwinian naturalism clashes with their religious belief absolutely — so much so that without intelligent design, evolution as an idea is anathema to them.

To these people, if God remains outside the realm of science, so much the worse for science.

If science is put above God, it is only logical that widespread atheism would be the result, say these people. But if God is put above science, society benefits.

To me, the biggest question is, can there be an approach to truth that embraces both pure science and a belief in God?

I don't think I can really answer that. I'm an agnostic when it comes to the question of how God and science ought to mix.

On the other hand, I would like to investigate the question of why for some people God and evolution science can't mix — at least, not without an admixture of intelligent design, a proposition that (I agree with Shermer) does not pass the test of true science.

I myself don't believe intelligent design is good science because the arguments in its favor don't stack up.

One major pro-I.D. argument posits that even a bacterial flagellum has so many chemical building blocks, each originated by one or more genetic mutations, that it's like a classical arch. An arch cannot stand on its own until its keystone is dropped into place, but the keystone cannot be put in until the rest of the arch is built, using some kind of scaffolding. None of the stones makes sense until all of the stones make sense. Ergo, just as there has to be a designer-builder behind the arch, there has to be one behind a bacterial flagellum.

But the mutation-driven changes in cell chemistry that gave the bacterium its flagellum are not necessarily like stones in an arch. They don't have to stand in any particular relationship to one another until the final change — the "keystone mutation," as it were — happens. After that, the other "stones," protein templates that have presumably arisen in the bacterial genome for independent reasons, can have their erstwhile utility (if any) rededicated to become pieces of the flagellar puzzle.

In hindsight, it looks to us as if something in or above nature must have "wanted" a highly useful motor-propeller to arise in single-celled living creatures ... and as if that is exactly what happened. A comprehensible evolutionary "target" has been hit. Ipso facto, there must have been a skilled, intentional archer taking careful aim at this comprehensible target.

For to think otherwise would seem to require us to assume that "random" genetic changes, occurring one at a time over umpty-ump millions of years, could actually manage to hit such a complex target as the genetic blueprint for a motor-propeller. The odds against that, no matter how much of the entire age of the universe you allocate for it to transpire, are (supposedly) vanishingly small. Ipso facto, intelligent design must be true.

A Darwinist, however, would respond — as would I — that what has actually happened is that a terribly nearsighted archer (nature, not God) has accidentally shot an arrow in the general direction of a large wall, has managed to hit the wall somewhere, and then we in his audience have proceeded to paint a target around the spot where the arrow struck.

It is quite true that when various and sundry mutational changes, taking place over a very, very long stretch of geological time, one day just happen to cohere and produce something useful like a flagellum, natural selection assiduously ratifies the result by culling out organisms that lack the new device. These organisms are less fit, they die out more readily than their fitter cousins, and their inferior genes don't tend to make it into succeeding generations. The full accretion of mutations that go towards producing the innovative flagellum do get passed on — and a target in effect gets painted by nature around the spot on the wall representing a motor-propeller.

That's at least one explanation of the bacterial flagellum that I believe is consistent with Darwinist evolution theory as it is understood today. There may be other, better ones. But my point is that you don't need to invoke an Intelligent Designer to explain how a structure as complex as a flagellum arose in nature.

One of the ground rules of science is that in explaining a thing, no more assumptions should be made than are absolutely necessary. This principle of scientific parsimony is also known by the colorful name Occam's Razor, attributed to the 14th-century English logician and Franciscan friar William of Ockham.

If the assumptions of Darwinist evolution theory fully cover how flagella might have arisen in nature — and they do — Occam's Razor forbids the additional assumption that a God must have taken a hand in the creative process.

The question of how yet-more-complex structures such as eyes, wings, and brains arose has a similar Darwinian answer. Take the eye. There were intermediate stages between having no eye at all and having the complex organ we have today. Perhaps the first stage was for certain skin cells to, as the result of a genetic mutation, become sensitive to light.

Meanwhile, other mutations might cause the hard bone beneath the light-sensitive cells to form a shallow cup, so the organism could begin to tell from which direction light is coming from ... a useful clue as to which way is up. Organisms happening to possess both mutational changes would be fitter than their clueless cousins and multiply more fruitfully. The stage would be set for more mutations to turn the cup behind the proto-retina fully into an enclosing orb with a pinhole in it, thereby to allow an image of the outside world to come into focus.

Further genetic changes could then arrange to morph yet more skin cells into a crude lens for the eye-in-the-making, so that objects at various distances could be brought into clear focus. Etc., etc., etc. Eventually, you have an organism that in advanced age needs bifocals.

These Darwinian explanations for how things like flagella and eyes might arise without divine assistance are admittedly quite speculative. Most of the intermediate evolutionary stages no longer exist, and their original possessors did not, alas, fossilize. It is hard or impossible to find a bacterium with a proto-flagellum these days. Hard to find an extant primitive creature with a shallow cup where an eye socket ought one day to form.

But advocates of intelligent design have at least as difficult a row to hoe. After all, they are trying to prove a negative. They are trying to prove that Darwinian incrementalism did not, and could not, account for complex biological structures.

One version of the "proof" asserts that things like eyes, wings, and flagella are "irreducibly complex." There is simply no Darwinian pathway whatsoever by virtue of which living creatures could go from being wholly without eyes to being possessors of the complex organs we observe (and have) today.

All hypothetical mutational pathways go through, as it were, impassable swamps of evolutionary territory, according to this logic. Mutations are required that make no adaptive sense — until they are complemented by a host of other, equally senseless mutations, and finally the "keystone," whether flagellar or visual, is set in place. Individually, these mutations actually drain their possessor organisms of their very Darwinian fitness. They cause the organism to waste time and chemical energy making proteins that do nothing of benefit to the organism, or that actually poison the organism's chances of survival. Only when the full complement of mutant protein templates is in place in the organism's genome does the point of the exercise become clear: an innovative motor-propeller, or the novel light-gathering capability of a sunken patch of skin.

Hence, the argument for intelligent design goes, you can't get from being eyeless to having eyes by following a Darwinian road map. There has to be something else going on.

This is an argument that tries to prove a negative, and then turn it into a (supernatural) positive. The negative: Darwin was wrong about the power of random heritable variation, abetted by natural selection, to account for all the complexity of living creatures today. The positive: God, as Intelligent Designer, must have intervened at uncountable junctures along the way.

A second version of the argument, subtly different from the first but coming to the same conclusion, is that maybe, just maybe — in the abstract, conceptual realm, mind you — there might be a purely Darwinian pathway from eyelessness to eyes, but the chances of the "blind watchmaker" which evolution has been dubbed finding it in the few billion years our world has existed are slim and none.

It's like programming a computer to break the most elaborate ciphers known to those in the intelligence community. In theory, any cipher can be broken by a straightforward computer program, simply by trying every possible master key, one key after another after another. In practice, there aren't enough computer CPU cycles in the current age of the universe to scratch the surface of the problem.

It's like that with evolution, this second argument for intelligent design goes. There hasn't been enough time for blind luck to locate the evolutionary pathways that produce flagella, eyes, wings, brains, etc., without guidance from above.

Those who make this argument do a bit of back-of-the-envelope math and find that the numerical probability of nature's just accidentally hitting an evolutionary target on the list summarized above — eyes, wings, brains, flagella, etc. — is much smaller than is acceptable, if we are to believe that evolution's "watchmaker" is purely blind.

Hence, the negative proposition becomes a positive one: if there is an eye, then there must be a Designer of that eye.

My reaction to that argument is that it does not take into account the sciences of complexity.

Complexity science is only about forty years old, and as the new kid on the block it has its defenders and naysayers. It is related to the theory of chaos, though it claims to stand on its own as a legitimate science. Its basic discovery is that nonequilibrium dynamical systems in nature tend to gravitate to a mathematical locus called the "edge of chaos."

A dynamical system is one that by its very nature changes. Many dynamical systems change in a highly orderly and predictable way, while others are chaotic. The ones that are chaotic are exquisitely sensitive to initial conditions, to an extent that a butterfly beating its wings in Rio can cause a tornado in Texas. The outcome is deterministic — bound to happen — yet we can never predict that outcome.

A open, nonequilibrium dynamical system takes in and expels matter and energy, thereby immunizing itself at least temporarily to entropy. It can exist in highly ordered states, or it can be in chaos, depending in part on the rate of energy flow through it. But the sciences of complexity have found yet another region that its dynamics can inhabit: the edge of chaos.

At the edge of chaos it is subject to surprising, unpredictable changes which nonetheless gracefully persist for long periods of time. Truly chaotic systems create surprise, but lack graceful persistence.

Certain open nonequilibrium systems — those that we call alive — naturally seek and find the edge of chaos. They establish themselves at the point of enduring, graceful dynamical poise. If they are perturbed, they gravitate back to the poised state, and in so doing they give birth to yet more evolutionary surprises.

Living systems that evolve in a Darwinian sense have a hidden tendency to find the edge of chaos, and to return to it if disturbed — so say the advocates of complexity science. In so doing, they make for the nearly inevitable creation of high levels of biological complexity over evolutionary timescales.

The sciences of complexity give us one way to refute the argument of intelligent design's proponents that flagella and eyes, wings and brains are just too improbable to have arisen without divine guidance.

Sunday, February 11, 2007

Dayton, TN, to Dover, PA

From Monkey Girl: How the War on Evolution Came to a Courtroom in a Small Town at

The ultimate veracity of evolutionary theory and the mountains of geologic and genetic evidence supporting it mean little to true believers. These evolutionary doubters ... include about 25 percent of the nation's science teachers.

That snippet comes from a review by Kit R. Roane of Edward Humes' Monkey Girl, the story of the recent trial in Dover, Pennsylvania, in which the local school board's attempt to insert "intelligent design" into the high-school biology curriculum was challenged (successfully) by anti-creationist evolutionists.

It continues to astound me that such a large percentage of those who should know better — trained science educators — doubt Darwinism. Roane writes that "intelligent-design advocates insist that gaps in evolutionary data equal flaws in evolutionary theory." Yes, there are gaps in the data. But these gaps are constantly being filled in by new fossil evidence. It seems that so many doubters won't be satisfied unless they see a time-lapse movie of dinosaurs turning into birds. Even then they'd probably say it was a hoax perpetrated by the folks who brought us the phony moon landing in 1969.

Roane, a senior writer with U.S. News & World Report, says:

In what must come as a cruel twist to evolutionists, nature may carry part of the blame here. Recent evidence, Humes writes, suggests that human beings are "genetically disposed to believe in mysteries, miracles, God, and faith."

What bothers me most about all this creationism vs. evolution stuff is how it divides us so cruelly. The proponents of intelligent design seem to want it exactly that way:

Championed by a retired University of California, Berkeley, law professor named Phillip E. Johnson and the Seattle-based Discovery Institute, intelligent design is brilliant mainly for what it doesn't say. Explicit references to God are eliminated. Instead, intelligent-design advocates insist that gaps in evolutionary data equal flaws in evolutionary theory. Their mantra has been to "teach the controversy," eschewing direct religious connotations in favor of emphasizing life's "irreducible complexity," which, they argue, points toward the hand of a mysterious force, an intelligent designer.

Johnson exhibits little of the fire and brimstone of his creationist counterparts. But Humes demonstrates that beneath the gentle exterior lurks the mind of a trial lawyer, one bent on the destruction of evolutionary theory. Humes explains Johnson's game plan thus: "Hammer the wedge into the tree of science hard enough, ... add the alternative of intelligent design, and the tree will fall."

In support of this reading, Humes cites the Discovery Institute's 1998 " Wedge Document," which promises to replace evolutionary materialism with "a science consonant with Christian and theistic convictions."

How sad, that we all have to undergo this culture war!

Saturday, February 10, 2007

Religion, Darwin, and a Mind for Poetry

Here is a snippet from"Missing Link," an article by critic-at-large Jonathan Rosen in The New Yorker of February 12, 2007: "Darwin, in his autobiography, noted that, as he grew older, he completely lost the ability to read poetry. He wondered if this was a symptom of mental decline, but it seems symbolic of a change in the fabric of his intellectual life ... ."

The article is an umbrella review of several recent books on the life of Alfred Russel Wallace, who independently discovered the force of nature which Charles Darwin, in his 1859 book On the Origin of Species, called natural selection. Wallace, also a British naturalist, puzzled out the same answer Darwin did to the question of how existing species could evolve into new ones over time. A younger man than Darwin, he also lacked Darwin's upper-crust connections into the scientific establishment of the day. In fact, it was a hopeful Wallace sending his manuscript on the subject to Darwin for review that prompted Darwin to break his two-decade silence and hurry Origin into print.

Darwin today gets the lion's share of credit for providing a scientifically impeccable explanation for biological evolution, while Wallace's name has faded into obscurity. As Rosen shows in his article, this was in large part because Wallace never gave up his convictions about God, spiritualism, and the supernatural realm. Despite "coolly articulating the materialist mechanisms by which the simplest organisms morphed into human beings," Wallace never stopped "arguing that our existence offers evidence of divine agency."

For his part, as Darwin aged his world view edged from quiet agnosticism over into forthright atheism. There was "a change in the fabric of his mental life" by virtue of which he lost his taste for poetry.

There seem to be two ways in which to take the Bible seriously. One is to read it literally; the other is to understand it poetically and metaphorically.

If you read it literally, you are a fundamentalist. You think you cannot square such an approach to scripture -- "God said it, I believe it, and that settles it" -- with Darwinian evolution, so you work to keep Darwinism out of high-school biology classes.

If you read the Bible with a poetic mindset, you have little trouble with evolution. Things poets say match reality on some higher, non-literal plane; everyone knows that.

It is almost as if the debate is all about which circuits and structures of the brain are predominant. Evidence for this comes from "Rewiring the Brain," a review by Mathew Blakeslee in Discover Magazine of two new books about the latest research into neuroplasticity.

Neuroplasticity is science-speak for how adult human brains can be taught new tricks, despite a longstanding belief to the contrary. The books are Sharon Begley's Train Your Mind, Change Your Brain and Norman Doidge's The Brain That Changes Itself. The Begley book, writes Blakeslee, speaks of

... a remarkable collaboration forged just a few years ago between Western neuroscientists and senior Tibetan monks. Their spiritual leader, the Dalai Lama, who brokered much of the discourse, comes across as remarkably astute and friendly to science.

This unusual syncretic exercise between the academy and a major world religion ... involves measurable, replicable effects of Buddhist meditation practices on the mind and brain. This rigorous mental training drives neuroplasticity in ways that awe many of the scientists studying it. Brain scans reveal that the neural activity of highly trained monks is off the charts, relative to meditation novices, in [brain] circuits that involve maternal love (caudate), empathy (right insula), and feelings of joy and happiness (left prefrontal cortex). Even when these monks are not meditating, their brains bear the imprints of their psychic workouts. The latter two structures, for instance, are anatomically enlarged.

Is there a brain region for poetry? "Brain Region Linked to Metaphor Comprehension," an article by Sarah Graham for Scientific American, suggests that the left angular gyrus region of the brain is at least partially responsible for grasping metaphors. This is a brain region that is

... more developed in humans than in other primates and is located in the brain at the junction of areas specialized for processing . "While it would be premature to conclude that the angular gyrus is the 'metaphor center' of the human brain," [researcher Vilayanur S.] Ramachandran says, "we suggest that the evolution of the dominant angular gyrus contributed enormously to the evolution of many quintessentially human abilities, including metaphorical — and other abstract — thinking."
It is interesting that metaphor processing is a function at a junction: that of touch, hearing and vision. Three ways of knowing come together amicably in the angular gyrus. This region of the brain looks to be one that biblical literalists don't trust much. Perhaps they could learn to do so by exploiting some of their God-given neuroplasticity.

Saturday, September 30, 2006

More on String Theory's Troubles

Recently, in String Theory into the Dustbin?, I talked about the doubts that are surfacing among physicists concerning string theory, the "theory of everything" that tries to unite quantum mechanics with Einsteinian relativity by positing that there exist, or ought to, a master set of equations from which the laws of both domains fall nicely out. The search for that master set has now gone on for over 30 years with, alas, no sign that the final answer is any closer at hand.

The Trouble
Indeed, as critic-at-large Jim Holt points out in "Unstrung," in the Oct. 2, 2006, New Yorker, enlargements to the theory designed to rescue it from its original inadequacies have robbed it of its hoped-for simplicity, elegance, and beauty. Two new books which I mentioned in my earlier post, Not Even Wrong, by Columbia University mathematician Peter Woit, and The Trouble with Physics, by Lee Smolin at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, now say it's completely bogus science.

String theory, which has also been called superstring theory, is (according to Holt) not yet even a full-fledged scientific theory. It "remains a seductive conjecture rather than an actual set of equations." At its base is the idea that the fundamental components of matter are not elementary particles, like quarks and leptons, but vibrating "strings" no more substantial than “tiny one-dimensional rips in the smooth fabric of space.” That is, all quarks (protons and neutrons are made of quarks) and leptons (an electron is a lepton) are basically strings.

For this to be so, apparently there have to be six more spatial dimensions than the three we see. That's what the mathematics tells us, at any rate. There seems to be no way to observe those extra dimensions, which have "curled up into some microgeometry that makes them invisible." An analogy given by Holt is to a stretched-out garden hose, which from a distance seems to represent a one-dimensional line, but from closer up reveals "a second dimension, curled up into a little circle."

But the extra dimensions required to make string theory work at all in unifying quantum mechanics with Einstein's theory have led to a conundrum: there are more than one mathematical way to model the invisible dimensions. Enter the "M-theory" of string guru Edward Witten, "the first physicist to be awarded the Fields Medal, considered the Nobel Prize of mathematics."

"In addition to vibrating strings, M-theory allowed for vibrating membranes and blobs," writes Holt. By encasing string theory in the more commodious M-theory, Witten in 1995 showed how "five seemingly distinct theories" into which the original string theory had split "were mere facets of something deeper" — and even less subject to empirical verification, it seems.

Unfortunately, "the non-uniqueness problem" which stood then at five models and counting has now "grown to ridiculous proportions," according to Holt's reading of Woit and Smolin. "At the latest count, the number of string theories is estimated to be something like one followed by five hundred zeros."

That's a lot of facets. Each represents a possible universe. Our universe, for example, is presumably modeled by a particular one — "with its own 'local weather' and history" — of these 10500 theories. But which model is right for us, and how do we tell?

Or, looked at another way,
What if all these possible universes actually exist? Perhaps every one of them bubbled into being just as our universe did. (Physicists who believe in such a “multiverse” sometimes picture it as a cosmic champagne glass frothing with universe-bubbles.)

Talk about non-empircal! How would we ever verify or refute the claim that there are 10500 other universes besides ours? Yet it's the contrary assertion that interests me. Some string theoirsts are now embracing the "anthropic principle" as a way of limiting the overfecund theory of strings to only this one known universe. (See also this article for more on the anthropic principle.)

Supporters of the anthropic principle recognize that, per Holt, "most of these [alternate] universes will not be biofriendly, but a few will have precisely the right conditions for the emergence of intelligent life-forms like us." The principle they support suggests that "the fact that our universe appears to be fine-tuned to engender life is not a matter of luck."

The principle itself states, perhaps a bit circularly, that "if our universe weren’t the way it is, we wouldn’t be here to observe it." We're here, though, and (so say the principle's boosters) we ought to be permitted as scientists to use the principle "to weed out all the versions of string theory that are incompatible with our existence, and so rescue string theory from the problem of non-uniqueness."

"Smolin and Woit," however, says Holt, "view the anthropic approach as a betrayal of science." It puts scientists in the position of hanging all their hopes for a "theory of everything" on a claim that "our universe appears to be fine-tuned to engender life." That strategy has at least two drawbacks. One, there's no way to falsify the anthropic claim, which violates philosopher of science "Karl Popper’s dictum that if a theory is to be scientific it must be open to falsification." In fact, the anthropic principle is little more than a truism, a "claim so obvious or self-evident as to be hardly worth mentioning." Two, it figuratively puts man back at the center of the universe, a position of privilege he lost when Copernicus told us the solar system was heliocentric.

Science has, over the last several centuries since Copernicus, sought to counter man's anthropic chauvinism by discovering that our sun is an ordinary star in the hinterlands of one of the billions of galaxies in the universe, the Milky Way. Then came Darwin's revelation that all of us sentient creatures descend from apelike ancestors. Evolution, say Darwinists, programmed us with certain inbuilt tendencies to believe what science disproves, one of those biases being that Someone Up There, beyond the natural world, favors us especially. Some of the freethinkers who resist using the anthropic principle to constrain string theory complain that elevating that principle to the apex of all science could let God back into the picture bigtime.

According to this 1999 article from Reason magazine, which doesn't mention string theory but does talk about the anthropic principle:
Patrick Glynn['s] 1997 book God: The Evidence asserts that recent scientific developments constitute a "powerful — indeed, all-but-incontestable — case for what once was considered a completely debatable matter of 'faith': the existence of soul, afterlife, and God." ... He adds [in a March 1998 interview]: "The anthropic principle puts the antitheists, the people who are arguing against the existence of God, in a very tough spot."

Unless physicists come up with some new super-duper master theory which picks out our universe from all the countless string theory possibilities, there seem to be only two tenable string-friendly strategies, beyond simply calling the ground rules of our particular cosmos brute facts without any scientific explanation. One is the multiverse idea, and the other is the anthropic principle. Neither appeals to Woit or Smolin, which is why they aren't string-friendly.

According to this review in The New York Times of his book The Cosmic Landscape: String Theory and the Illusion of Intelligent Design:
Leonard Susskind, a founder of [string] theory and one of its leading practitioners, brazenly lays out this no-boundaries attitude on the first page ... . His research, he declares, "touches not only on current paradigm shifts in physics and cosmology, but also on the profound cultural questions that are rocking our social and political landscape: can science explain the extraordinary fact that the universe appears to be uncannily, nay, spectacularly, well designed for our own existence?"

Susskind, says the review:
... proposes that those 10500 possibilities [represented by string theory] represent not a flaw in [the] theory but a profound insight into the nature of reality. Each potential model, he suggests, corresponds to an actual place — another universe as real as our own. In the spirit of kooky science and good science fiction, he coins new names to go with these new possibilities. He calls the enormous range of environments governed by all the possible laws of physics the "Landscape." The near-infinite collection of pocket universes described by those various laws becomes the "megaverse."

Megaverse, multiverse ... same idea. The anthropic principle tells us absolutely nothing, and there need not be a God.

So we seem to have a situation in which, in the absence of emipirical evidence one way or another, scientists are having (per Holt in The New Yorker) "a high-school-cafeteria food fight" over what is mostly theology by any other name.

Monday, September 11, 2006

Skepticism vs. Intelligent Design

Intelligent Design theory, or ID, is the version of creationism recently put forth by a cadre of credentialed scientists and others who say Darwin was wrong about evolution. In Why Darwin Matters: The Case Against Intelligent Design, his latest book, Michael Shermer argues that it is ID that is wrong, for a whole host of reasons.

Shermer is the founding publisher of Skeptic magazine and the executive director of the Skeptics Society. His monthly column appears in Scientific American. He is the author of other books about skepticism, which he says is basically the intellectual posture of "thoughtful inquiry." He calls science essentially a body of knowledge that is testable. Science is thus "applied skepticism" (p. 48).

By those lights, he says ID theory is not science at all. Why Darwin Matters catalogues the reasons why it fails the scientist's "six principles of skepticism" (pp. 48-53):
  1. Hume's Maxim, or, what is more likely?
  2. The Known and the Unknown, or, before you say something is out of this world, first make sure it is not in this world.
  3. Burden of Proof, or, extraordinary claims require extraordinary evidence.
  4. Either-Or Fallacy, or, disproving A does not prove B.
  5. The Fossil Fallacy, or, one datum does not a science make.
  6. Methodological Naturalism, or, no miracles allowed.

Tim M.
Evolution and
the Myth of
Because it is basically a debate-style rebuttal, Shermer's book does not provide the uninitiated with a broad overview of what Darwinism's claims are. (For that, try Evolution and the Myth of Creationism, by Tim M. Berra.) It is, rather, an overview of the case against the case against Darwin.

For example, ID proponents assail the large "gaps" that exist in the fossil record. By no means is every rung on evolution's ladder attested to by a known fossil, creationists charge (and evolutionists admit). When evolutionists unearth another ladder rung, partially filling a gap, creationists merely "respond that there are now two gaps in the fossil record!" To this debating ploy Shermer cries foul (p. 51). This sort of pointed retort is a mainstay in Shermer's argumentation.

As I understand it, Darwin's theory of evolution, as updated by modern science, tells us that all biological species today — including Homo sapiens — descend from other species. In the distant past, there came to be (in ways unspecified by Darwinism) the first simple kinds of organisms. These were, we now realize, the early bacteria. Over the first one billion years or so of life on earth (see p. 86), they evolved into various sorts of more internally complex, yet still single-celled, bacteria.

Then, 1.7 billion years ago, the first multicellular life appeared. 1.2 billion years ago, higher algae forms arrived. 650 million years ago, the primitive Ediacaran fauna came into the waters of the world. Finally, about 500 to 550 million years ago, in the Cambrian period, there was an explosion of complex multicellular life from which virtually all species today descend.

But how, Darwin asked, could one species change into another? His answer: by descent with modification. Heritable factors unknown to Darwin (we now call them genes) can be modified slightly (by mutations and other processes) from generation to generation. These minor modifications can accumulate over time, making, eventually, a new species.

Accumulation over time only happens to the modifications that help their possessors survive and reproduce under their particular environmental conditions. "Natural selection" ruthlessly weeds out the modifications that don't help, Darwin said. The ones that aren't weeded out — the ones that make for greater "fitness" — then get passed down through subsequent generations. To these original modifications are added, over the eons, more fitness-inducing modifications as they happen by random chance.

If this transpires in a population that is in any way cut off from the rest of its kind — say, by a geographic barrier — the isolated population will eventually accumulate enough modifications that it cannot mate with its erstwhile kin, even if a reunion occurs. It will have become a new species.

Each externally observable minor modification en route to a new species could conceivably be preserved as an individual fossil. However, that's not likely. It's not even likely that every species in a given line of species-by-species descent has left a fossil. The ones that weren't fossilized constitute the permanent gaps, the rungs in the evolutionary ladder that we can never document.

Creationists long ago complained of those gaps. To their complaints, Intelligent Design proponents have now added a new wrinkle. They say that the ladder's rungs are not "missing links" at all. Rather, they were never there in the first place, because they couldn't have existed in principle.

Looked at another way, ID says there was in fact something of an "evolutionary ladder," in that more complex species did arrive on the scene well after earlier, simpler ones. The fossil record does not lie in this regard. It's just that the rungs on the ladder have sometimes been spaced much farther apart than evolution by natural selection could deal with alone.

Darwinian evolution, ID proponents say, in effect has short legs. It can manage to ascend a ladder with close-spaced rungs, corresponding metaphorically to minor "microevolutionary" changes within established species. But barriers exist, say IDers, which, when encountered, prevent natural selection's short leg span from going any further up the ladder of increasing complexity.

These barriers are ones of "irreducible complexity." Typically, the amount by which complexity increases in a new species, compared with its simpler ancestral one, is too great for unaided natural selection to manage, rung by rung. Or, if you will, at certain points on this imaginary ladder of increasing evolutionary complexity the rungs are spaced much too far apart.

That's where the Intelligent Designer comes in. Whether the Designer is God or some other supernatural or extraterrestrial intelligence, he, she, or it must have intervened to lift evolving species up to higher rungs of the complexity ladder too distant to be climbed to straightforwardly by natural selection alone.

Or so says ID theory. Well-known ID theorists such as Michael Behe point to various organs and functions of existing species — the propulsive flagellum of bacteria, the wing, the eye, human blood clotting — that supposedly had to arise all in one fell swoop. Missing just one component, each would be useless. But each component calls for a separate Darwinian modification to be preserved by natural selection. How could such tiny step-by-step changes, accumulated over eons of time, make a wing?

By means of exaptation, for one, Shermer writes:
... a feature that originally evolved for one purpose is [in exaptation] coopted for a different purpose. The incipient stages in wing evolution had uses other than for aerodynamic flight — half wings were not poorly developed wings, they were well-developed something elses — perhaps thermoregulating devices. The first feathers in the fossil record, for example, are hairlike and resemble the insulating down of modern bird chicks. Since modern birds probably descended from bipedal therapod dinosaurs, wings and feathers could have been employed for regulating heat — holding them close to the body would retain heat, stretching them out would release heat. (p. 69)

What about the idea broached by ID theorist William Dembski that there is "no free lunch"? During the course of evolution, what he calls "complex specified information" (CSI) has to have experienced jumps whose magnitude is more than nature's laws, augmented by chance, permit. Ergo, there must be a Designer.

The DNA in genes encodes huge numbers of bits of information. The number of bits that have to be added to a genome to produce an eye, says Dembski, is far too large to happen via the workings of natural law, or chance, or any combination of the two. Since the necessary new information is (by virtue of its "complexity") too improbable to happen at random, and since it is "specified" information (it achieves an independently statable goal, e.g., vision) an intelligent being must have furnished it.

Or, as Shermer summarizes the claim, Dembski's "Law of Conservation of Information says that natural causes such as chance and evolution cannot increase the complex specified information content of an organism by more than 500 bits of information" (p. 72). Dembski's law, if correct, might count as the Fourth Law of Thermodynamics.

But the law is not correct. Shermer finds it, rather, "abundantly clear that information in the natural world — through DNA, for example — is transferred and increased by natural processes" (p. 73).

For example, the earliest bacteria had no nuclei, mitochondria, etc. These organelles which higher organisms, us included, today inherit in their constituent cells arose when the earth's original bacteria took other bacteria into themselves intact. When they did that, their genomes increased sharply in size and complexity.

In similar fashion, functions like human blood clotting arose when existing genes in an ancestral genome were duplicated by some sort of copying mistake, and then the duplicates evolved new functions while the originals kept on doing what they did before (see pp. 73-74). The total amount of information in the genome typically went up with each gene duplication by more than Dembski's 500 bits. Dembski's law is accordingly wrong.

What of related claims that the Second Law of Thermodynamics itself makes evolution impossible? That law says a closed, isolated system will inevitably "run down" into a chaos-like equilibrium over the course of time. This is entropy. But life on earth, seen as a thermodynamic system of energy and heat, has done just the opposite. Its order, complexity, and diversity have increased.

Shermer points out (pp. 81-82) that this vision of an entropy-shackled biosphere is a straw man. The earth is not a closed, static system. It is open and dynamic, receiving external energy from the sun. Accordingly, it
... slips in and out of thermodynamic equilibrium. The sciences of nonlinear dynamics and of chaos and complexity theory show that [such] systems can spontaneously self-organize into more complex systems when they are in states of thermodynamic nonequilibrium. When a system is out of balance, energy flowing in and out of the system triggers the parts of the system to interact with one another locally, and these coupled interactions reverberate throughout the system to sustain it. Autocatalysis, or feedback loops within the system, can cause it to grow in complexity. From these self-organized autocatalytic interactions emerge complexity and order. All of this happens without any top-down input [as from an Intelligent Designer]. Evolution no more breaks the Second Law of Thermodynamics than one breaks the law of gravity by leaping into the air. (p. 82)

Shermer gives many dozens of such refutations of Intelligent Design theory in his book. He complements this material with discussions of how true science works, and how multiple avenues of scientific inquiry have together established the factuality of Darwin's theory of evolution beyond all reasonable doubt. Yet, he grouses, national polls show nearly half of Americans still don't believe in Darwin.

His chapters on "Why People Do Not Accept Evolution" and "In Search of the Designer" attempt to say why: people resist science in general; they object when science undermines religious tenets; they fear that being "descended from apes" degrades our humainty, ushering in moral degeneracy and nihilism; and (from the liberal side) they hate it that evolutionary theory seemingly sets limits on how far we humans can progress.

Based on polling he and a coworker have done, Shermer also finds that we who believe in God typically are thought to do so for "emotion-based" and "fear-averse" reasons, even by fellow believers (see pp. 36-38). There are intellectually based reasons for believing in God — seeing the world as exquisitely designed, for example — but those who were polled tended to attribute such rational motives to themselves and the emotion-based motives to others.

Not surprisingly, Shermer sees this "intellectual attribution bias" as evidence that we humans have evolved in such a way as to be prone to such a bias. "We are pattern-seeking as well as pattern-finding animals," the author notes (p. 38). We look for and expect design, even where it patently doesn't exist. When we think we find it, we assume a designer. We assimilate that expectation to our understanding of God.

But, Shermer argues (pp. 40-42), using logic one may find a bit strained, even if life on earth is designed, it could just as well be the handiwork of an advanced extraterrestrial intelligence. Why God, necessarily?

It is at this point in his exposition that he ventures boldly into theology. Though Shermer says he spent several years of his youth as an evangelical Christian and a creationist, he apparently no longer believes in the sort of God who would intervene in natural processes.

Echoing the American Protestant neo-orthodox theologian Langdon Gilkey, Shermer says (p. 43), "Far from being a mere intelligent watchmaker, God is the 'transcendent source of all existence' who creates ex nihilo — from nothing." And, per German Protestant theologian Paul Tillich: "God does not exist. He is being itself beyond essence and existence ... ."

And so:
If we think of God as a thing, a being that exists in space and time, it constrains God to our world, a world of other things and other beings that are also restrained by the laws of nature and the contingencies of chance. But if God is the maker of all things and all beings visible and invisible in heaven or earth, God must be above such restraints ... "The question of the existence of God can be neither asked nore answered," Tillich explains. "If asked, it is a question about that which by its very nature is above existence ... "

If there is a God, the avenue to Him is not through science and reason, but through faith and revelation. If there is a God, He will be so wholly Other that no science can reach Him ... .

Shermer could have left out the theology, maybe. He cites Gilkey and Tillich, thinkers noted for stressing the "otherness" of God at the expense of his approachability through Christ, the Church, and the sacraments. This is a basically Protestant view that has its merits and demerits. Catholics such as myself may well find it problematic. And what of Jews, Muslims, and members of non-monotheist religious traditions?

The neo-orthodox theological approach appeals to its proponents on the basis of such concepts as existential anguish, or the fear of non-being. But Shermer has made it clear that he dislikes such "emotional" justifications for believing in God. Thus it would seem he is being inconsistent.

What's more, his foray into theology really has no part in his argument for Darwin. Darwin is right on the merits of the case, whether or not one believes in God. He is right whether one, if a theist, embraces Protestant neo-orthodoxy or not. The scientific rightness of evolution theory is the main thrust of Shermer's argument, and he makes the argument well.

His epilogue to his argument — and to his book — makes a welcome spiritual, as opposed to theological, point. "There are many ways to be spiritual," Shermer writes, "and science is one in its awe-inspiring account of who we are and where we came from."

He embellishes the subject of the spirituality of science by citing the late astronomer and Cosmos host Carl Sagan:
The universe is all there is, or ever was, or ever will be ...

Our contemplations of the cosmos stir us. There's a tingling in the spine, a catch in the voice, a faint sensation as if a distant memory of falling from a great height. We know we are approaching the grandest of mysteries ...

The cosmos is within us. we are made of star stuff ... We've begun at last to wonder about our origins, star stuff contemplating the stars, organized collections of ten billion billion billion atoms contemplating the evolution of matter, tracing that long path by which it arrived at consciousness here on the planet Earth and perhaps throughout the cosmos. Our obligation to survive and flourish is owed not just to ourselves but also to that cosmos, ancient and vast, from which we spring. (pp. 157-158)

"That is spiritual gold, and Carl Sagan was one of the most spiritual scientists of our epoch," Shermer writes. Then he continues, "How can we find spiritual meaning in a scientific worldview? Spirituality is a way of being in the world, a sense of one's place in the cosmos, a relationship to that which extends beyond oneself."

In an endnote, Shermer extends his lionizing of Sagan's scientific spirituality by quoting the final passage from the astronomer's sci-fi novel Contact. I find the passage itself somewhat inscrutable, so I'll quote Wikipedia's interpretation:
In a kind of postscript, Ellie [Arroway, the novel's protagonist], acting upon a suggestion by the [extraterrestrial] senders of the Message, works on a program which computes the digits of π to record lengths and in different bases. Very, very far from the decimal point (10^20) and in base 11 (postulated number of dimensions in M theory, after 1995), it finds that a special pattern does exist when the numbers stop varying randomly and start producing 1's and 0's in a very long string. The string's length is the product of 11 prime numbers. The 1's and 0's when organized as a square of specific dimensions form a perfect circle.

You can argue (the Wikipedia article shows how) that there is actually no "message from God" in π, which is the ratio of the circumference of any circle to its diameter. It's not clear whether there's "hidden meaning" of any sort in a numerical expansion of that number's digits. (I myself am not even clear: does Ellie Arroway's expansion actually yield the stated results, or is this just a literary device on Sagan's part?) But I think such niggling misses the point.

The point is more along the lines of the human need to, as Shermer says, be in fruitful, spiritual relationship with "that which extends beyond oneself." Ellie Arroway finds such a relationship by, in effect, being in dialogue with the cosmos. She looks for and receives a message from afar. She decodes the message. She finds a hidden, universal meaning. In that dialogue itself she encounters what she was looking for all along, as a human person.

The important thing spiritually is not in the fact of the π pattern (if it exists). It is rather in the experience of the dialogue. Science is a way to have a true spiritual encounter with "all there is, or ever was, or ever will be." In the words of Martin Buber in I and Thou, it is yet another way to "speak the primary word I–Thou."

Thursday, August 17, 2006

String Theory into the Dustbin?

An article in the August 21, 2006, issue of Time has indirect bearing on the evolution vs. Intelligent Design debate. Science writer Michael Lemonick, in "The Unraveling of String Theory," discusses a pair of new books that challenge a current orthodoxy in physics:
Not Even Wrong, by Columbia University mathematician Peter Woit, and The Trouble with Physics, by Lee Smolin at the Perimeter Institute for Theoretical Physics in Waterloo, Ont., both argue that string theory (or superstring theory, as it is also known) is largely a fad propped up by practitioners who tend to be arrogantly dismissive of anyone who dare suggest that the emperor has no clothes.
As I understand it, string theory, which Lemonick says has been around now for nearly 30 years, is an attempt to unify quantum mechanics and Einsteinian relativity, which don't go together all that easily. In quantum theory, energy comes in discrete packets that have a set minimum size. In relativity, energy is a smooth, continuous variable that can be as small as you like.

String theorists hope that such apples-and-oranges differences might be harmonized under the proper mathematical umbrella. Their math requires that there be not four dimensions of spacetime, but ten or more. The ones we do not see have simply collapsed and become vanishingly small.

Furthermore, the smallest objects in the universe are no longer particles, according to the math of string theory, but "minuscule, vibrating loops and snippets of stuff resembling string," says Lemonick. "Bizarre as it seemed, this scheme appeared on first blush to explain why particles have the characteristics they do. As a side benefit, it also included a quantum version of gravity and thus of relativity."

Woit and Smolin, themselves disenchanted string zealots, now assail the theory for having grown way too complex. Each successive new wrinkle in the fashioning of the theory has been smoothed over with "solutions [that] often introduce yet another layer of complexity," in Lemonick's words. "Complexity isn't necessarily the kiss of death in physics, but in this case the new, improved theory posits a nearly infinite number of different possible universes, with no way of showing that ours is more likely than any of the others."

And that is what piques my interest. Genome mapper and evangelical Christian Francis Collins talks in The Language of God: A Scientist Presents Evidence for Belief of the anthropic principle, which in at least one of its versions notes that (per Wikipedia) "If any of the fundamental physical constants [of our universe] were sufficiently different, then life as we know it would not be possible and no one would be around to contemplate this universe we live in."

There are some number of numerical constants in physics that, in terms of their values, apparently just are what they are. They cannot be derived mathematically from other, simpler numbers or relationships. For example, the gravitational constant, G, which relates the masses of objects along with the distance separating them to the attractive force between them, is one of the "just so" constants of physics.

Presumably, life as we know it could never have evolved in a universe with a different set of constants. Collins believes this is a sign of God's handiwork. Admittedly, this theistic conclusion is not quite a slam dunk, as there are many ways of undermining its logic (see this Wikipedia article for some of them). One is that it is an unremarkable truism: the only reason we are even here to wonder at the issue is because these physical constants were, for whatever reason, just right.

Still, I think the anthropic principle does furnish suggestive (though not conclusive) evidence for God ... unless, that is, there actually do exist — to repeat the phrase used above — "a nearly infinite number of different possible universes, with no way of showing that ours is more likely than any of the others." In that case there would almost certainly be, by sheerest chance, at least one universe within such a collection whose creatures are, like us, capable of mulling over the deeper significance of the anthropic principle.

Here is where the Lemonick article gets very interesting, then. Woit, he says, raises the issue of whether string theory qualifies, even, as a legitimate part of science!

Here's how Lemonick puts it:
Now, it seems, at least some superstring advocates are ready to abandon the essential definition of science itself on the basis that string theory is too important to be hampered by old-fashioned notions of experimental proof.

And it is that absence of proof that is perhaps most damning. Physicists have a tolerance for theory; indeed, unless you were there to witness a phenomenon yourself — the Big Bang, say — it will always be, at some level, hypothetical. But the slow accretion of data and evidence eventually eliminates reasonable doubt. Not so — or at least not yet — with strings.

"It's fine to propose speculative ideas," says Woit, "but if they can't be tested, they're not science." To borrow the withering dismissal coined by the great physicist Wolfgang Pauli, they don't even rise to the level of being wrong.
Nobody has yet thought of a way to test string theory empirically, by generating concrete hypotheses based on it and subjecting them to experimental verification. That makes string theory, in a way, much like Intelligent Design theory. ID, the proposal that a power outside this world furnished earthly evolution's directionality by, at various critical junctures, fashioning new, "irreducibly complex" structures like bacterial flagella and eyes, allows of no experimental verification either, say its critics — of which I am one.

On the one hand we have a notion, string theory, which undergirds the possibility of a manifold of universes, sometimes called a "multiverse." Of that manifold entity our universe is putatively just one of a huge number of actual universes, not just imaginable ones, each one slightly different in its fundamental, arbitrary constants of physics, such that the anthropic principle no longer serves as a (weak or strong) argument that there must be a God. String theory can accordingly be thought of as crypto-atheistic.

On the other hand we have a notion, Intelligent Design theory, which suggests evolution couldn't have been undirected; there has to have been an artificer working behind the scenes. ID is accordingly crypto-theistic.

Now it appears that both of these seemingly antithetical proposals share a common characteristic: neither can be falsified by the experimental testing of hypotheses derived from the respective theory itself.

Scoffers at ID say it is consequently bogus science. One would have to have just fallen off the turnip truck not so suppose that a good deal of such hostility to ID is motivated by the personal commitment of the scoffer to a purely materialistic worldview. According to this Wikipedia article on materialism:
Science uses a working assumption, sometimes known as methodological naturalism, that observable events in nature are explained only by natural causes without assuming the existence or non-existence of the supernatural.
Materialism, like string theory, is thus subject to the accusation of being crypto-atheistic. Its proponents (as well as a great many other people who are not strict philosophical materialists, myself included) extol the scientific method of inquiry which requires all hypotheses to be experimentally falsifiable. I wonder: would those same materialists, then, agree that string theory too should be chucked into the dustbin of scientific history, on similar grounds to ID?

Friday, August 04, 2006

The Language of God

Francis S.
The Language
of God
A new book by Francis S. Collins, The Language of God: A Scientist Presents Evidence for Belief, represents perhaps the best effort yet to reconcile Darwinism and faith. Collins is a physician-geneticist who headed the Human Genome Project, the collaboration which mapped the sequence of the 3 billion "letters" or base pairs in the DNA every human cell contains, one copy from each parent. The 56-year-old American is a committed evangelical Christian who believes in a God that cares about us and wants to be in fellowship with us. Collins also believes unreservedly in Darwinian evolution.

The main thrust of Collins's book is that belief in Darwin, and in science in general, need not imperil one's faith in God.

Collins himself began his adult life as an atheist who was nonetheless bestirred to question his own lack of belief. He responded to two aspects of his personal inner experience with a certainty that there must be a God and a commitment to evangelical Protestantism.

The first aspect of his personal experience that he couldn't explain from the point of view of a skeptical atheist was his realization that there seems to be a Moral Law common to all human beings in all places and times, from which we each derive a basic, universal notion of right and wrong. According to this Moral Law, acts of altruism are given the highest ethical value, everywhere in the world, even when they are done in secret and can stimulate no possible reciprocity. Evolution theory can't explain that.

Then there is the universality of human wonder at the world and about its Creator: a spiritual hunger which, again, science can't satisfy or even explain. Collins says he found a sense of, yes, joy in the intense longing itself — as did the well-known Christian explicator, C.S. Lewis, in Surprised by Joy. Collins builds on Lewis this way (p. 35):
He [Lewis] describes the experience as "an unsatisfied desire which is itself more desirable than any other satisfaction." I can recall clearly some of those moments in my own life, where this poignant sense of longing, falling somewhere between pleasure and grief, caught me by surprise and caused me to wonder from whence came such strong emotion, and how might such an experience be recovered.
These two common threads of human experience, Moral Law and spiritual hunger, neither of which science can explain, convinced Collins that God is real. Yet Collins always wanted to be a scientist and to do science in the way it is meant to be done: to observe phenomena in the material world and then to search for the wholly naturalistic theories that will explain them. Such investigations can yield insights into, among other things, how to cure diseases and alleviate suffering.

Science alone can explain a lot, says Collins, but there are events it can shed little light on, such as whatever led up to the Big Bang, the "singularity" approximately 14 billion years ago which most scientists agree represented the origin of the universe. We may also never know for sure how life on Earth began, some 4 billion years ago.

But most of what science has at one time either gotten wrong or been wholly unable to deal with has historically been filled in or corrected by later science, Collins points out. Early astronomers thought the sun moved around the Earth; Copernicus, Galileo, and Kepler proved the opposite. Early naturalists assumed living things were too complex not to have been directly created by God; Darwin showed a way for nature, acting alone, to build up the biosphere's complexity gradually, over eons of time. Human intuition has it that matter and energy are two different things; Einstein showed they are one.

Since the dawn of modern scientific inquiry, remarks Collins, every time we humans have found gaps in our scientific uncerstanding of the material world, we have appealed to a "God of the gaps" to fill them. Nowadays we encounter a gap in explaining life's origins, so some believers in God have proposed "the appearance of DNA and RNA as a possible opportunity for divine creative action" (p. 92). Collins counsels caution here: "Faith that places God in the gaps of current understanding about the natural world may be headed for crisis if advances in science subsequently fill those gaps" (p. 93).

It might be argued that Collins himself inserts God in a "gap" in our knowledge when he ascribes our altruism and spiritual capacity to divine influence, beyond science's reckoning. His premise here is clearly that God's work within us is not open to empirical inquiry. Hence, these aspects of our inner experience are not scientific "gaps" at all, any more than (say) our uniquely human quality of self-awareness can be fully "explained" as a product of natural evolutionary forces.

Whatever the soul may be, Collins suggests, it can never be a legitimate subject of scientific investigation. Ergo, our altruism and spiritual capacity, as twin aspects of soul, cannot possibly represent explanatory "gaps" which science could one day close. We who love science's logical consistency remain free to seek God, without calling him a "God of the gaps."

Collins himself is trying (I think successfully) to fill a gap: the one between creationists and scientific/academic atheists.

Creationists believe that the stories of creation in Genesis (there are two of them) are more or less literally true. Young Earth Creationists believe in a strict literal interpretation of Genesis which informs them that God made all things in heaven and earth, including humankind, over a six-day period. Extrapolating from information in the Bible, the famous Bishop Ussher dated the inception of the world at 4004 B.C.

Among the leading scientific and academic atheists whom Collins cites are the Darwinian biologist Richard Dawkins, the philosopher Daniel Dennett, and the entomologist/sociobiologist Edward O. Wilson. Dawkins, a leading exponent of scientific atheism, has asserted in articles like "Is Science a Religion?" and in books like The Selfish Gene, The Blind Watchmaker, Climbing Mount Improbable, River out of Eden, and A Devil's Chaplain such things as (see pp. 163ff.; p. 195):
The final decisive edge enjoyed by scientific naturalism will come from its capacity to explain traditional religion, its chief competition, as a wholly material phenomenon. Theology is not likely to survive as an independent intellectual discipline.
It is fashionable to wax apocalyptic about the threat to humanity posed by the AIDS virus, 'mad cow' disease, and many others, but I think a case can be made that faith is one of the world's great evils, comparable to the smallpox virus but harder to eradicate.
[Dawkins's definition of faith is] blind trust, in the absence of evidence, even in the teeth of evidence.
The universe we observe has precisely those properties we should expect if there is, at bottom, no design, no purpose, no evil, and no good, nothing but blind pitiless indifference.
Collins opposes both worldviews. Young Earth Creationism simply nullifies scientific inquiry outright and forces young people who don't want to leave their parents' faith into "effectively committing intellectual suicide" (p. 178). Scientific atheism à la Dawkins gets tangled up in inconsistencies such as holding that there is no good or evil, yet claiming that "faith is one of the world's great evils."

A special type of creationism which Collins takes on all by itself is Intelligent Design theory. The brainchild of Phillip Johnson, a lawyer, along with scientists Michael Behe, William Dembski, and numerous others, ID is the notion that many structures in Earth's life forms are "irreducibly complex." For instance, says Behe, the flagellum of a bacterium is something like an "outboard motor." Used for propulsion, it consists of many interlinked proteins. Each protein serves a particular function; indeed, one of them acts as a sort of "universal joint" such as you might find in the axle of a car.

A protein is a long chain of molecular building blocks, the amino acids. Genes are sequences of DNA, hundreds or thousands of base pairs long, that specify or "code for" these chains of amino acids and thereby call forth the production by living cells of specific proteins. There is presumably a specific gene in flagellar bacteria that codes for the "universal joint" protein.

According to Collins (p. 185), Behe observes that there are about 30 proteins in a bacterial flagellum. That suggests, of course, that there are basically the same number of genes in the bacteria's genome to code for the flagellar proteins. Behe claims that this assemblage of thirty or so genes could not have arisen in step-by-step fashion with each gene individually ratified by Darwinian natural selection, because no one of the thirty proteins coded for by the genes has any utility in itself. Only when you put all thirty proteins together do you have a working flagellum.

Behe and other proponents of ID make similar arguments about, among other things, the eye and the dozen or more proteins that compose the highly effective "human blood-clotting cascade." These and other structures/functions found in living species are said by IDers to exhibit irreducible complexity and thereby to disprove the gradual, step-by-step nature of Darwinian evolution via natural selection. Accordingly, there must instead have been an Intelligent Designer who fashioned these structures intentionally.

Yet in every case, Collins shows, there is good reason to believe that Intelligent Design theory is simply incorrect about these elaborate structures being irreducibly complex. For instance, says Collins (p. 192), " ... comparison of protein sequences from multiple [species of] bacteria has demonstrated that several components of the flagellum are related to an entirely different apparatus used by certain bacteria to inject toxins into other bacteria that they are attacking."

Genetically and evolutionarily, this "type III secretory apparatus," which is less complex than a flagellum, is a way station to the latter. And there may be an as-yet-undiscovered evolutionary stepping stone to the former ... and so on, and so on, and so on, until the whole notion of irreducible complexity gives up the ghost.

Furthermore, contrary to Intelligent Design's assumptions, says Collins, it is actually rather easy, over the span of evolutionary time, to alter the influence a given gene exerts by way of the protein for which it codes. If you are Mother Nature, all you have to do is introduce into a particular genome a copy of an existing gene, call it A. A continues to perform its original mission, while A', the copy, is free to mutate and thereby code for a brand new protein. Get just the right bunch of these putatively "useless" new proteins together — I'm reading between Collins's lines here, by the way — and a "type III secretory apparatus" can become a flagellum. And, says Collins, gene duplication and subsequent mutation happen quite a lot in nature, down through countless generations.

Which by no means implies there's no God. All it really does to harm faith is to require that certain Bible passages not be interpreted literally. Instead, says Collins, people of faith should be open to the idea that a God outside time who made the laws of the universe foreknew what those laws would produce via evolution: moral creatures whose spiritual hunger would bring them one day into personal communion with Him.

P.S. Here is an excellent New York Times review of several recent books, including Collins's, on all sides of the subject of whether belief in God makes sense for a scientific Darwinist.