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No Two Alike: Human Nature and Human Individuality

“Why am I me?” is an important – and unanswered – question that George Dyson asked his father, Freeman Dyson, at age 8. It’s at the heart of Judith Rich Harris’ work in No Two Alike: Human Nature and Human Individuality. It’s the essence of the tension between our desire to be like others and our need to have status amongst our peers. I’ve read and reviewed Harris’ previous work, The Nurture Assumption (written in 1998), so in many ways her work here builds on her theories, which I’ve previously studied. No Two Alike is a dozen years old as I write this, having been published in 2006. However, many of the observations that she makes and the research she cites still isn’t widely known by parents.

The Consistency Fallacy

We believe that human behavior is a fixed constant. We believe after meeting a person that their behavior is the same whether hanging out with their friends on a Saturday night or in the second row at church on Sunday morning. However, nothing could be further from the truth. (See How to Be Yourself for more on this example.) Kurt Lewin said that behavior is a function of both person and environment. (See more in my review of Moral Disengagement.) In The Lucifer Effect, we learned, through the Stanford prison experiment, just how powerful the effect of environment can be. We learned how people can behave one way in one environment and completely differently in another.

Johnathan Haidt explains how our behaviors are driven by a rider, an elephant, and a path. Our behaviors are rationally, emotionally, and environmentally based. (See The Happiness Hypothesis and Switch.) It would seem silly to believe that people behave consistently when there are so many levels to the way that we make decisions, most of which aren’t available to our consciousness.

Maybe we’re fooled by the belief that others are consistent, because we know how hard it is to change our own behaviors. (See Change or Die and Willpower.) Whatever the reason, we believe that we’ll behave consistently across time and circumstances despite the evidence to the contrary.

Not Knowing and Not Questioning

One of the challenges of our human brains is that we stop questioning things when we forget where we learned them. One of the reasons for the extensive notes I take – and the extensive effort I put into writing these blogs – is to preserve the knowledge of where I found things. Over the years, I’ve found a few errors in citations. It was defective steel in the Brooklyn Bridge that required additional winding – not the Golden Gate Bridge, as was reported in one source. Nor does “Indiana” mean a headman and advisor to the king in Zulu – as was reported in Dialogue. (This turned out to be a simple transcription error.)

The problem is that people assumed that the environment made a difference, that parents made a difference, that bad kids were the responsibility of parents, and that they deserved some blame for their children not turning out to be model citizens. That assumption is something that Harris challenges.

More Alike

With at least 50% of the genetics between them and a home environment that is completely the same, one would expect siblings to turn out substantially more alike than they do. Anyone with two or a few children quickly realizes that they’re not the same. But the question is why? If 50% of our makeup is hereditary, then what is the other 50% made of? Surely it must be the environment – but The Nurture Assumption and No Two Alike both systemically eliminate many of the theories for why people are different.

Birth order – perhaps because of the popularity of the book Born to Rebel – is given considerable time as a potential actor in the play of differing personalities, but its effects are tiny – if they exist at all. Otherwise, the environment that siblings are raised in seems to be relatively identical.

Microenvironments and Mutations

Identical twins are – at least genetically – identical at the time of their separation. It’s one egg and sperm that separates into two people. However, sometimes genetic differences – very small differences – occur due to random mutations. These random mutations can make very small changes in twins, which can sometimes drive them apart.

We know that some genes are environmentally triggered. Why Zebras Don’t Get Ulcers speaks of Fetal Origins of Adult Disease (FOAD) – and how these aren’t generically triggered per se. Rather, they are genetic responses to environmental stressors. Two twins sitting side by side – or quite literally attached to one another, as in conjoined twins – may still experience life, just slightly differently, and those slight differences may make all the difference.

Imagine a peg board like the one in the TV show The Price is Right. The Plinko board allows for a token to be dropped at the top, and the token bounces its way down through the pegs to its final resting place. Small differences can cause a token to go left or right at each peg. This is also known as the Butterfly Effect, after the 1972 article by Edward Lorenz titled “Does the Flap of a Butterfly’s Wings in Brazil Set Off a Tornado in Texas?” The short is that, in a chaotic system like weather, we have no hope of capturing enough data to predict everything.

The same seems true of how our children’s personalities will develop. There are so many factors that we’ll never be able to accurately predict – or effectively shape – our children’s personalities. Each child lives in their own microenvironment, one unique just to them.

I vividly remember the day my son discovered that there were people who would steal. We were at the Indianapolis Zoo, and my wife and I had split up so I could look for something for my brother and his Fiancée’s wedding. She had our son and a wagon that we brought for him to ride in. She called me on the radios we bought to ask if I had taken the wagon. She had left it outside an exhibit. When she came back it was not to be found. I was already outside putting the gift in the car and began looking through the parking lot to see if I could find the person who had taken the wagon. Soon after, they joined me, and I eventually found the person who had taken the wagon and positively identified it, because my jacket was still in it. That was the day that my son learned about theft.

I couldn’t have shaped those events. I couldn’t have decided when he learned of theft. I had to respond to it when it came. The microenvironment of his life taught him a lesson that day – whether I was ready for it or not.

Academic Investigation

Rich is an interesting person, sitting outside the traditional academic world and focused on integrating disciplines instead of advancing a single discipline. Instead of being an expert in sociology or neurology, she artfully weaves the findings from each into a tapestry of ideas that point the way towards explanations for why children raised in the same household turn out so differently.

She’s like the chief detective in a murder-mystery book, who looks for the inconsistencies in one story and for other ways to understand or explain what is happening. This is exciting for me, because it resonates with my desire to connect thoughts from disparate disciplines and connect them or point out inconsistencies.

Amateurs

Often the term “amateurs” is used as a derogatory term by established elite, who believe that amateurs aren’t capable of the kind of progress that professionals – and particularly academic professionals – are. However, used as a pejorative term, it’s a weak one. Just months before this post, Smithsonian magazine posted “Will the Next Great Scientific Discovery Be Made by Amateurs?” It shares a few of the recent discoveries that amateurs participated in – and expectations that more discoveries will come from amateurs.

Amateurs hold a special place. They’re not bound by the assumptions of the profession. They don’t have to do things the same way that everyone else does them. They’re free to innovate and find their own way. (See The Medici Effect and Diffusion of Innovations.)

Consider that the research says that most therapies – whether talk-based or pharmacological – don’t work. They have marginal, if any, improvement for the patients. What does matter is a relationship – called therapeutic alliance – though it’s not clear that your bartender couldn’t give you that. (See The Heart and Soul of Change and Warning Psychiatry Can Be Hazardous to Your Mental Health.)

In fact, much of the entire field of psychology rests on pillars of salt. The psychological tests that many use have been repeatedly debunked but continue to be used in settings where their accuracy doesn’t approach any level of reliability. (See The Cult of Personality Testing.)

European Orphanages

For the most part, it seems that if you do a reasonable job with raising your children and don’t veer off course beyond the boundaries of what society expects, children are not permanently harmed by their childhoods, no matter what the psychologist of the week wants to make them believe. It’s easier to make someone believe that their unhappiness is their parents’ fault than it is to get someone to face the fact that they’re responsible for their own lives.

However, there are some cases – particularly, cases where children were deprived of stable social relationships – that do have lasting impacts. Orphanages in Eastern Europe denied children access to loving relationships and provided them with only the necessities of life. As a result, some of the adults rescued from this environment showed a host of psychological issues.

I had the opportunity to meet one such adult who had been in an orphanage in Eastern Europe. After several years with loving parents from the United States, she was overly friendly with the men she would meet – and several took advantage of that friendliness. She’s still seeking to heal the wounds left with her from her time in the orphanage. She’s still trying to learn how to be an adult and understand her intrinsic value.

Most children who are raised don’t have the social deficits that these children have and will grow up with personalities that, while not always pleasant for the parents, are in a normal range.

Children Teaching Children

Often parents today worry whether they’re spending enough time with their children. They’re concerned that they aren’t enriching their lives enough. However, Harris points out that, in most traditional societies, parents don’t interact with children much. Instead, children are raised by older children. A child is separated from their mother’s warm embrace at the time of the next child – typically after three or four years of age. After that, the older children of the group would look after the younger children.

Depending upon the size of the group, it may stay together or split along age lines, and eventually on age and gender lines. Smaller groups have one large group of children, and larger groups have age-specific groups. The self-categorization that happens in the children causes them to sort into groupings that are the most like them when the groups get large enough.

Self-Categorization

There are many words that could be used to describe me. Father. Son. Brother. Entrepreneur. Developer. Technologist. Pilot. The list goes on and on. No word fully expresses all my personality, but each can describe a facet of it. More importantly, I can switch between which facet of my personality I identify with as easy as crossing a room. All adults and children do this as well. One moment they identify with some aspect of themselves or a group to which they belong – and they can quickly change to another identification.

This is important, because each of the categorizations leads to a different set of behaviors. As a father, I take on an authoritarian (or authoritative) stance, helping my children to realize that I’m not their peer. As a son, I take an opposite attitude. The category that I leave myself in the most frequently begins to have dominance in how I behave and how others perceive me.

Bad Fit Stereotypes

Harris explains that she’s no good at fitting into stereotypes. I’m proud to say that I’m no good at it either. Use the developer stereotype, and you’ll find yourself thinking of someone who is so shy, they stare at people’s shoes when others talk to them. Use the entrepreneur stereotype, and you’ll expect me to hurl myself down mountains and surf the big waves in Hawaii. No matter what stereotype you attempt to use… I just don’t fit in.

Accepting this fact, that I don’t fit in, has taken many years. Children are – quite rightfully – disturbed by the lack of “fitting in,” which, in some sense, means fitting in with stereotypes.

Battle of Three Systems

Harris explains her theory that there are three different systems in operation in the human brain at the same time. There’s the relationship system that works to maintain favorable relationships with people. The second system is the socialization system that makes people want to fit in with a group. The third, and latest to develop system, is the status system that makes humans want to be better than one’s rivals. The status system gets much of its input from the mind reading systems in the brain – which, though functional at age four, needs some time to get good at its job. (See Mindreading.)

The personality we see from our children is the result of this epic battle. At one level, they want to make close friends, except when that means they don’t fit into a group – however they chose to define that group. More challenging, however, is how someone can be both a member of the group and above it in status at the same time.

As people move from group identification, where stereotypes live, to individual relationships, different mental processing systems are in use. As a result, Al Campanis can believe that Jackie Robinson is a great player and at the same time believe that blacks shouldn’t be managers. (See Mistakes Were Made for more on this example.)

Parental Influence

At the end of the day, do or don’t parents have impact on their children? They clearly have impact on their children, but most of it is indirect. The people that they move their child near and the groups that are formed by children dramatically influence a child’s personality and “lot in life.” Between random events and microenvironments, it’s impossible to really shape a child’s personality.

However, the good news is that this lets parents off the hook. They don’t have to be ashamed if their child doesn’t turn out perfect. They can – and should – still do what they can to support their children just like our ancestors did. However, we need not worry that we’re “doing parenting right,” because there is no one recipe when there are No Two Alike.