Judith Rich Harris has an engaging writing style and covers a wide range of research in her book. There are a number of references to her earlier book, The Nurture Assumption.
The Economist wrote about Harris first book in a 1998 review: Parents, she argues, have no important long-term effects on the development of the personality of their children. Far more important are their playground friends and neighbourhood companions. Ms Harris takes to bits the assumption which has dominated developmental psychology for almost half a century. Freud was wrong; Philip Larkin was wrong. It is not your mum and dad who fuck you up, but the other kids on the block and those fellow brats in the classroomMum and dad surely cannot be ditched completely. Young adults may, as Ms Harris argues, be keen to appear like their contemporaries. But even in those early years, parents have the power to open doors: they may initially choose the peers with whom their young associate, and pick that influential neighbourhood. Moreover, most people suspect that they come to resemble their parents more in middle age, and that peoples child-rearing habits may be formed partly by what their parents did. So the balance of influences is probably complicated, as most parents already suspected without being able to demonstrate it scientifically. Even if it turns out that the genes they pass on and the friends their children play with matter as much as affection, discipline and good example, parents are not completely off the hook.
The mystery is why people even identical twins who grow up in the same home with the same genes end up with different personalities. The detective is Harris herself, a crotchety amateur, housebound because of an illness, who takes on the academic establishment armed only with a sharp mind and an Internet connection. Harris the author scrupulously follows clues; Harris the protagonist drives the story forward through force of character, arriving at a theory of personality that could be said to describe herself.
Your socialization system figures out how to conform to your group. Your relationship system figures out how to get along with each person. Your status system figures out how to compete. It monitors people’s reactions, gathering information about how smart, pretty, weak or talented they think you are. It looks for virtues, activities and occupations at which you’re most likely to best your peers. It notices tiny differences between the way people regard you and the way they regard others in your peer group, or even your twin. By choosing pursuits based on these differences, it magnifies them. It drives you to be different.
This is the paradox behind the book’s subtitle. Human nature causes human individuality; the mental systems that we share are also the ones that distinguish us. But if these three systems are, as Harris concludes, the “perpetrators” of individuality as we know it, the mystery of how we got here gives way to the mystery of where we’re going. The perpetrators remain at large. The evolutionary forces that gave us distinctive personalities don’t end here. Human nature isn’t finished with human individuality, or with itself.
No Two Alike is a fascinating book because it is a story about us and the people around us. Harris wonderful story-telling brings alive what could otherwise have been a dull and dreary scientific paper.
Tomorrow: The War of the World