Chapter 1: "NURTURE" IS NOT THE SAME AS "ENVIRONMENT"

Heredity and environment. They are the yin and yang, the Adam and Eve, the Mom and Pop of pop psychology. Even in high school I knew enough about the subject to inform my parents, when they yelled at me, that if they didn't like the way I was turning out they had no one to blame but themselves: they had provided both my heredity and my environment.

"Heredity and environment" -- that's what we called them back then. Nowadays they are more often referred to as "nature and nurture." Powerful as they were under the names they were born with, they are yet more powerful under their alliterative aliases. Nature and nurture rule. Everyone knows it, no one questions it: nature and nurture are the movers and shapers. They made us what we are today and will determine what our children will be tomorrow.

In an article in the January 1998 issue of Wired, a science journalist muses about the day -- twenty? fifty? a hundred years from now? -- when parents will be able to shop for their children's genes as easily as today they shop for their jeans. "Genotype choice," the journalist calls it. Would you like a girl or a boy? Curly hair or straight? A whiz at math or a winner of spelling bees? "It would give parents a real power over the sort of people their children will turn out to be," he says. Then he adds, "But parents have that power already, to a large degree."

Parents already have power over the sort of people their children will turn out to be, says the journalist. He means, because parents provide the environment. The nurture.

No one questions it because it seems self-evident. The two things that determine what sort of people your children will turn out to be are nature -- their genes -- and nurture -- the way you bring them up. That is what you believe and it also happens to be what the professor of psychology believes. A happy coincidence that is not to be taken for granted, because in most sciences the expert thinks one thing and the ordinary citizen -- the one who used to be called "the man on the street" -- thinks something else. But on this the professor and the person ahead of you on the checkout line agree: nature and nurture rule. Nature gives parents a baby; the end result depends on how they nurture it. Good nurturing can make up for many of nature's mistakes; lack of nurturing can trash nature's best efforts.

That is what I used to think too, before I changed my mind.

What I changed my mind about was nurture, not environment. This is not going to be one of those books that says everything is genetic; it isn't. The environment is just as important as the genes. The things children experience while they are growing up are just as important as the things they are born with. What I changed my mind about was whether "nurture" is really a synonym for "environment." Using it as a synonym for environment, I realized, is begging the question.

"Nurture" is not a neutral word: it carries baggage. Its literal meaning is "to take care of" or "to rear"; it comes from the same Latin root that gave us nourish and nurse (in the sense of "breast-feed"). The use of "nurture" as a synonym for "environment" is based on the assumption that what influences children's development, apart from their genes, is the way their parents bring them up. I call this the nurture assumption. Only after rearing two children of my own and coauthoring three editions of a college textbook on child development did I begin to question this assumption. Only recently did I come to the conclusion that it is wrong.

It is difficult to disprove assumptions because they are, by definition, things that do not require proof. My first job is to show that the nurture assumption is nothing more than that: simply an assumption. My second is to convince you that it is an unwarranted assumption. My third is to give you something to put in its place. What I will offer is a viewpoint as powerful as the one it replaces -- a new way of explaining why children turn out the way they do. A new answer to the basic question of why we are the way we are. My answer is based on a consideration of what kind of mind the child is equipped with, which requires, in turn, a consideration of the evolutionary history of our species. I will ask you to accompany me on visits to other times and other societies. Even chimpanzee societies.

Beyond a Reasonable Doubt?

How can I question something for which there is so much evidence? You can see it with your own eyes: parents do have effects on their kids. The child who has been beaten looks cowed in the presence of her parents. The child whose parents have been wimpy runs rampant over them. The child whose parents failed to teach morality behaves immorally. The child whose parents don't think he will accomplish much doesn't accomplish much.

For those doubting Thomases who have to see it in print, there are books full of evidence -- thousands of books. Books written by clinical psychologists like Susan Forward, who describes the devastating and longlasting effects of "toxic parents" -- overcritical, overbearing, underloving, or unpredictable people who undermine their children's self-esteem and autonomy or give them too much autonomy too soon. Dr. Forward has seen the damage such parents wreak on their children. Her patients are in terrible shape psychologically and it is all their parents' fault. They won't get better until they admit, to Dr. Forward and themselves, that it is all their parents' fault.

But perhaps you are among those doubting Thomases who don't consider the opinions of clinical psychologists, formed on the basis of conversations with a self-selected sample of troubled patients, to be evidence. All right, then, there is evidence of a more scientific sort: evidence obtained in carefully designed studies of ordinary parents and their children -- parents and children whose psychological well-being varies over a wider range than you could find in Dr. Forward's waiting room.

In her book It Takes a Village, First Lady Hillary Rodham Clinton has summarized some of the findings from the carefully designed studies carried out by developmental psychologists. Parents who care for their babies in a loving, responsive way tend to have babies who are securely attached to them and who develop into self-confident, friendly children. Parents who talk to their children, listen to them, and read to them tend to have bright children who do well in school. Parents who provide firm -- but not rigid -- limits for their children have children who are less likely to get into trouble. Parents who treat their children harshly tend to have children who are aggressive or anxious, or both. Parents who behave in an honest, kind, and conscientious manner with their children are likely to have children who also behave in an honest, kind, and conscientious manner. And parents who fail to provide their children with a home that contains both a mother and a father have children who are more likely to fail in some way in their own adult lives.

These statements, and others of a similar sort, are not airy speculation. There is a tremendous amount of research to back them up. The textbooks I wrote for undergraduates taking college courses in child development were based on the evidence produced by that research. The professors who teach the courses believe the evidence. So do the journalists who occasionally report the results of a study in a newspaper or magazine article. The pediatricians who give advice to parents base much of their advice on it. Other advice-givers who write books and newspaper articles also take the evidence at face value. The studies done by developmental psychologists have an influence that ripples outward and permeates our culture.

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