Judith Rich Harris's The Nurture Assumption (New York:The Free Press, 1998) has all the makings of a dangerous book. As presented by the media, it is a marvelous justification for middle-class parents to buy better schooling for their kids, draining off even more support from public schools and from efforts to give all children the opportunity to develop to their fullest. Put your kids "into the best school (you can) find -- a school with smart, hard-working kids," she writes. "A school where no one makes fun of the one who reads books and makes As." After that don't worry, because it's not what you do that counts, Harris says. Their friends at school and on the street are far more important.

If ever a message was designed to please busy professional parents, it's this one. Not only are parents suddenly absolved for whatever they might do to mess up their kids' psyches, but they're also told that, with a notable few exceptions, there isn't much that's proved useful in compensating for schools' failings -- or in making schools better, for that matter. Furthermore, Harris's book comes endorsed by six prominent psychologists: it's "stunning," "vital," "truly revolutionary," and "a paradigm shifter," they say. How can you argue with that?

Not very easily. When I read the reviews, I was appalled by the way Harris and her cheering section seemed ready to wash their hands of tens of thousands of our children who aren't in good public schools in nice suburbs, or in private schools that can set their own admission standards. What a recipe for making our two-tier education system that much worse! What a prescription for future social problems!

But when I read the book, I discovered that it has a second message, which I've yet to see mentioned by the chattering classes. The "nurture assumption" -- the idea that the 50 per cent of our behavior that isn't more or less determined by our genes is determined by parent-child relations -- has kept psychologists, educators and parents from focusing on real questions, Harris says. To back up her argument, she re-examines a mass of psychological studies -- and also draws on several observations she's made herself. Language is supposed to be something parents teach their children, she notes, yet how do you explain immigrant children who quickly learn to speak the language they hear around them? And how did generations of upper class Englishmen end up sounding and acting like their fathers, even though they had practically no contact with them?

The important group is the peer group, she contends: the neighbourhood kids, in the case of the immigrant child; the other boys at the exclusive English boarding school, for the young Brits. Not recognizing this is dangerous mistake, she says.

"The proliferation of meaningless research -- one more dreary study showing a correlation between parents' sighs and children's yawns -- has been substituted for useful investigation," she writes (page 353) It would be far better to research questions like "How do some teachers, some schools, some cultures, manage to ... keep the kids united and motivated?" And "Is there any way to keep the larger culture from having deleterious effects on the norms of teenagers' groups? How many does it take to make a group?"

She plaintively ends her lengthy list of possible research topics: "I have been unable, in this book, to give you answers to these questions, because the research has not yet been done."

Without a doubt it should be, and Harris's readable and interesting book should be used to see that it is. A first step is to recognize that the dangerous spin put on the book by the media has eclipsed Harris's second, more radical, message. What she is proposing is nothing less than finding out how to make groups function better, how to make schools and neighbourhoods work, how to change the world. The step after that is up to us.