Blinded by Science.

Nature via Nurture: Genes, Experience, & What Makes Us Human, by Matt Ridley (HarperCollins, 336 pp., $25.95)

This is a very strange book, and I am not quite sure what the author is attempting to achieve. At the very least it appears that he wants to shore up genetic determinism as the key factor in understanding human nature and individual behavior.

Genetic determinism is rational materialism's substitute for the religious notion of predestination; taking the place of God as puppet master are the genes, whose actions and interactions control who we are, what we think, and how we act. This reductionist view received a body blow recently when the mappers of the human genome found that we have only about 30,000 genes. Because of their understanding of human complexity, the scientists were expecting at least 100,000 -- and that means there are probably too few genes for strict genetic determinism to be true.

Ridley, a science writer and former U.S. editor of The Economist, tries to ride to the rescue. In doing so, he adds a twist that he hopes will overcome our apparent genetic paucity: Yes, he says, our genes decide who we are, what we do and think, and even with whom we fall in love. But, he posits, our molecular masters are not rigidly preset when we are born. Rather, they change continually in reaction to our biological and emotional experiences.

Hence, 30,000 are more than enough for a soft genetic determinism to be true -- which means that the battle between those who believe we are the product of our biology (nature) versus those who believe we are the result of our environment (nurture) can now end in a truce in which both sides win. We are indeed controlled by our genes, but they in turn are influenced by our experiences. Ridley says that the mapping of the genome "has indeed changed everything, not by closing the argument or winning the [nature versus nurture] battle for one side or the other, but by enriching it from both ends till they meet in the middle." To Ridley, the core of our true selves isn't soul, mind, or even body in the macro sense; we are, in essence, merely the expression of our genes at any given moment.

If this is true, then my perception of Nature via Nurture as so much nonsense was the only reaction I could have had, given my original genetic programming, as later modified by my every experience and emotion from my conception, through the womb, childhood, high school, college, practicing law, the death of my father, indeed up to and including the reading of this book. If that is so -- if I was forced by my gene expression of the moment to perceive this book as I have -- what have we really learned that can be of any benefit to humankind? We are all slaves to chemistry and there is no escape.

Even aside from such broader issues, Ridley does not make a persuasive case. Maybe it is my legal training, but I found his evidence very thin. He doesn't present proofs so much as resort to wild leaps of logic predicated on questionably relevant social science and facile analogies based on a few animal studies. These are simply not strong enough to be the sturdy weight-supporting pillars that his thesis requires to be credible. Let's look at just one example. He cites studies of monogamous prairie voles to suggest that humans only think they fall in love, when, in reality, what we call love is merely the expression of genes resulting in the release of the chemicals oxytocin and vasopressin. Claiming that he is not going to "start extrapolating anthropomorphically from pair-bonding in voles to love in people," he proceeds to do just that. Citing the vole studies and Shakespeare's A Midsummer Night's Dream -- in which a love potion makes Titania fall in love with a man with a donkey's head -- Ridley writes:

Who would now wager against me that I could not do something like this to a modern Titania? Admittedly, a drop on the eyelids would not suffice. I would have to give her a general anesthetic while I cannulated her medial amygdala and injected oxytocin into it. I doubt even then that I could make her love a donkey. But I might stand a fair chance of making her feel attracted to the first man she sees upon waking. Would you bet against me?

But shouldn't it take far more than measuring the physical effects of oxytocin on prairie voles to prove that something as complex, maddening, unpredictable, and wonderfully and uniquely human as romantic love can, in reality, be reduced to the mere expression of genes leading to chemical secretions? Not, apparently, to Ridley. "Blindly, automatically, and untaught, we bond with whoever is standing nearest when oxytocin receptors in the medial amygdala get tingled." Gee, if he'd known that, Bill Clinton could have purchased fewer copies of Leaves of Grass.

The most fascinating thing about this book is that Ridley inadvertently makes a splendid argument for intelligent design. At this point, I am sure Ridley's "I am utterly appalled" genes are expressing wildly. He is, after all, a scientific materialist in good standing. Yet, throughout the book, in order to make his arguments understandable, he resorts explicitly to the imagery of the guiding hand. He even gives it a name: the "Genome Organizing Device," or "G.O.D." Ridley claims that the G.O.D is "a skillful chef, whose job is to build a souffl?," consisting of the various parts of us and all other life on the planet. Note the language of intentionality in his description of the evolution of the human brain:

To build a brain with instinctive abilities, the Genome Organizing Device lays down separate circuits with suitable internal patterns that allow them to carry out suitable computations, then links them with appropriate inputs from the senses. . . . In the case of the human mind, almost all such instinctive modules are designed to be modified by experience. Some adapt continuously throughout life, some change rapidly with experience then set like cement. A few just develop to their own timetable.

But according to my lay understanding, this violates the theory and philosophy of evolution. The hypothesis of natural selection holds that species origination and change are promoted by genetic mutations. Those mutations that change the organism to make it more likely than its unchanged peers to survive long enough to reproduce are likely to be passed down the generations. Eventually, these genetic alterations spread among the entire species and become universal within its genome. It is through this dynamic evolutionary process of modification, the theory holds, that life fills all available niches in nature. It is also the process, although the details are not known, by which the primates now known as homo sapiens became conscious.

The philosophy of Darwinism posits that this evolutionary process is aimless, unintentional, purposeless, and without rhyme or reason. This means it has no biological goal: It just is. Hence, G.O.D. would not want to "build a brain," develop nature via nurture in species, or do any other thing. Yet, throughout the book, Ridley seems able only to describe what he thinks is going on using the language of intention. Could this be because Ridley's theories would require interactions that are so complex and unlikely that they would seem laughable if described as having come together haphazardly, by mere chance?

So what are we to learn from his insights? In terms of how we live our lives, not much beyond what common sense already tells us: Parents matter and should engage with their children; human teenagers enjoy doing what they are good at, and dislike doing what they are bad at; and so on. That much is harmless; but Ridley's deeper point is subversive of human freedom and individual accountability. He denies the existence of free will: Our actions are not causes but effects, "prespecified by, and run by, genes." Indeed, he claims unequivocally, "There is no 'me' inside my brain, there is only an ever-changing set of brain states, a distillation of history, emotion, instinct, experience, and the influence of other people -- not to mention chance."

Ridley asserts this as if it would be a good thing to learn that the complexity and richness of human experience could accurately be reduced to merely the acts of so many slaves obeying the lash of chemical overseers acting under the direction of our experience-influenced gene owners. "Nature versus nurture is dead," Ridley concludes triumphantly. "Long live nature via nurture."

Sorry. Maybe it's my genes, but I just don't buy it.