No Two Alike: Human Nature and Human Individuality Paperback – June 17, 2007

Great!

Whenever I read a science book that analyzes hard data to make radical claims, I immediately rush to read all the responses. The manner of the responses is what convinces me Harris's books are correct. So far the criticisms have been ideological, emotional, and focus on Harris's lack of credentials. (What doctorate means: You are hereby allowed to make money claiming this belief system is true.) Harris has no dog in this fight. Her rigor hit a nerve and made psychologists self-conscious about their rigor. So far nobody has dared argue against her data in any detail.Writing it in the style of a detective story is a serviceable way to propel the narrative. It reads like a personal memoir of a no-nonsense lady stubbornly in search of truth, with Joan as her trusty lance-bearer, while they battle against the stubborn momentum of popular myths.Harris took a cogently argued polemic and turned it into a meditation on the very methods by which science overcomes the confirmation bias, and the methods by which it does NOT.I am convinced there is no evidence that children's relationships with their parents has any affect on their adult relationships, and there has never been any evidence shown that birth order has an affect. If somebody has evidence that it does, show it. As Harris says, "Show me the data." If psychologists can't respond with data, the argument rests on the conclusion that Freudian psychology is based on a hunch.

One of the more fascinating aspects of being human is that we're all built from the same parts, yet we all have different personalities. What makes you you and me me? Confronted with this question, most people would respond that it's some blend of nature (the genes you inherited from your parents) and nurture (the environment you were raised in). Judith Rich Harris debunks that answer and replaces it with an elegant hypothesis about the true sources of human uniqueness.In the first part of her book, Harris takes developmental and social psychologists to task for over-emphasizing the influence of early childhood experiences on personality formation and not giving enough credit to what happens outside the home. She also maintains that developmental studies that don't screen for genetic influences are prone to confuse cause and effect. She shows how research that's been inadequately digested makes its way into mainstream culture, where it's regurgitated as pop truth. According to Harris, most of the conventional wisdom about birth order, home environment, parenting style, and the interaction of genes and the home environment does not adequately explain why we're different from one other.Having eliminated the usual suspects, Harris turns to Stephen Pinker's How The Mind Works as her starting point for solving the mystery of human personality. Pinker posits that our brains are organized into "mental modules" that perform discrete tasks. Some examples of modular systems are facial recognition, language acquisition, and our ability to postulate what other people are thinking (a theory of mind). All of these had evolutionary value to small tribes of wandering hominids, and evolved to better serve our survival needs.Harris' theory is that once we've figured out what part of a personality is accounted for by genes (a little less than half if you average the various studies), the remainder of a personality is created through the interplay of three mental systems: the relationship system, the socialization system, and the status system. Each of these systems evolved to deal with a pressing survival issue. The relationship system helps us attach to, and later relate to, specific individuals. The socialization system enables us to figure out the norms of our group so we can fit in. The relationship system is with us at birth, and the socialization system develops quite early in life. The slowest system to emerge is the status system, which we use to set ourselves apart from the other members of our group. The status system takes longest to develop because we need to be intellectually sophisticated enough to figure out who we are and what we're good at.These systems can issue contradictory directives. For instance, the generalizations of the social system war with the specificity of the relationship system. This explains why a person can dislike an ethnic group while getting along perfectly well with a neighbor who happens to be a member of that group. The socialization and status systems are often at odds: do I sacrifice my personal goals for the good of the group, or do what's best for me even if it harms the others? Most of a life's high drama involves trade-offs among these systems. What makes you unique among all the humans who have ever trod the planet is the way your mental modules process the stimulus provided by your particular environment.I wish we had more detail on how Harris' mental systems work. For instance, language acquisition theorists continue to go round on how much of our language facility is innate versus how much is instantiated by experience. Just as we have to memorize a lot of specific words to speak a language, we have to organize a lot of data - particular faces, facts about the people attached to those faces, rules, norms and prototypes of groups, specific information about our own skills and how people view us - to populate Harris' mental modules. Does the framework - eg grammar rules or the relationship module - precede the data, or does it emerge as the data is acquired? If the three systems are more innate than experiential, does this mean that more of our personality is influenced by genes than we currently believe? If it's experiential, by what process do we generate the proper responses to a specific situation? What triggers the appropriate neural assemblies and how do we make trade-offs between specific information and general rules?As Harris herself states, her theory needs to researched, tested and validated. The really exciting breakthroughs will come when we're able to correlate observational studies of human behavior with the genes and genetic switches that activate those behaviors. Behavioral geneticists are advancing into this new territory, which will help us lift the analysis of human personality out of the realm of metaphor and into the realm of hard science. Meanwhile, Harris has given us an elegant hypothesis, rich in implications, written in a clear and entertaining manner. As a theory, it explains an immense amount about why you're you and I'm me.

I don't have time to write a full review, so I'll just say that Harris's thinking is one of my crucial touchstones when thinking about human nature, human development, child-rearing, and other aspects of what makes humans the way they are.The sad story is that you pretty much never find this book on the "parenting" shelf in bookstores, even though it's the most important book any parent could read.

A thorough presentation of a controversial proposition, well supported with scientific evidence, excellently analyzed and presented in a clear, witty manner. This work follows her ground breaking and award winning initial article and book with a further exploration and intriguing addition of the processes by which children are socialized.

While the author is extremely knowledgeable about this topic, I found her writing style extremely laborious and too wordy. She probably could have said everything she needed to say in a lot less pages.

it is awesome. I would like recommend for everyone who is educating or starting to college education. It is about human nature and nurture. You will learn a lot of why human being selfish, lazy, and why identical twins, siblings have different interests and thoughts.

I read several books a week, and made numerous attempts to get into Judith Harris' volume. It is a subject I am quite interested in, and know something about, being a professional psychologist. So I was looking forward to reading it. Let me tell you though, this book needed some serious editing. In just the first 30-40 pages there are so many repetitive sentences, gratuitous self-references, false starts, second starts, third starts...I don't know where to begin...so I won't. I will simply say that Ms. Harris should read "The Elements of Style" or some other book on writing or argumentation. Say it, Judith. Say it clearly and say it one time. And if you tell the story of the conjoined twins who had differing personalities one more time I will shoot myself.

Great book. Some new ideas for an old problem.

I can only endorse what other 5 star reviewers have said about this book and will try not to repeat what they have already eloquently explained. Judith Rich Harris (JRH)' analysis of childhood development is light years ahead of so much else that has been written on this subject. As she explains, ideas on children's development since the second world war have been based on the assumption that bad parenting styles produce adult neuroses and bad behaviour (I am thinking of writers such as Alice Miller and her followers.) So much so, that it has become part of everyone's accepted explanation. But the influence of genetics has been completely downplayed or even denounced.JRH adopts what I would consider a scientific approach to the subject which had been sadly lacking in Freudian and post-Freudian analyses. She has read extensively in research studies and carefully thought about their validity. I am a follower of Karl Popper and, as such, find her approach very close to Popperian methodology (although I am not claiming that this is intentional on JRH's part). In other words, she does not dogmatically claim that her hypotheses are correct. She puts them forward as conjectures which may or may not be correct and invites further research and criticism.This is a must read book for anyone interested in the human condition.

Easy reading, explains a lot of the variation in people, helps with understanding

Super interesting and well written book. Recommended for anyone seriously interested in developmental psychology, personality psychology or psychology in general. I havent read the nurture assuption, but will do after having read this book.

An interesting take on why we turn out the way we do. And a welcome respite for parents who seem to be blamed for everything and anything that goes wrong in people’s lives.