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Why Are No Two People Alike? (Part 2)

(This post is the second in a two-part series on the work of Judith Rich Harris. See the first part here.)

As we concluded Part 1 of our exploration of Judith Rich Harris’s work on human personality, we had begun sketching out her theory by delving into the first of three systems that she believes carry the heavy lifting in determining how our adult personalities are formed.

The first system was the Relationship System, the “people information lexicon” we automatically begin building at birth to recall the details of the people we encounter throughout our lives. This mental Rolodex carries a lot of freight, but it’s only one cog in a larger system. The workings of the Relationship System start to impact us in a broader way as we begin computing statistics about all the people in our lexicon.

This leads us to start developing a second system: the Socialization System, which we use to figure out how we need to act to fit into the groups we’ll need to be a part of to become a member of society.

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Recall from Part 1 the definition of Socialization: “Acquiring the social behaviors, customs, language, accent, attitudes, and morals deemed appropriate in a particular society.”

When Harris says “particular society,” she also means “particular group” — we do not, of course, act the same around our parents as we do around our friends, our co-workers, our neighbors, or our own children. Each group has its norms, and we must learn them. Unless we are autistic or otherwise severely mentally challenged, we do just that! We do it by automatically using the information we’ve gathered, which is called implicit knowledge.

As Harris discusses in the book, even patients with severe dementia, Parkinson’s, or amnesia can recall all kinds of implicit or categorical knowledge. She refers to an amnesiac patient named Frederick who couldn’t remember that he’d played golf recently, but nonetheless didn’t forget anything about playing golf in general: He recalled all the mechanical knowledge, the lingo, the customs, and the rules. Just not his last round:

All memories are not alike; nor are all memory disorders. What Frederick had lost was his ability to form new memories of a sort called “episodic” — explicit memories of actual events, which can be consciously recalled and put into words. What he had retained was his semantic memories (factual knowledge, like the meaning of birdie) and his implicit or procedural memories (how to play golf). You may have episodic memories of being taught to play golf by your father, but your knowledge of how to play golf is procedural. Sad to say, you may lose your explicit memories of your father sooner than your implicit memories of how to play golf.

An Alzheimer’s patient may not remember meeting any specific man, but ask him what a man is, and he can describe one just fine. As we’ll see below, the systems are distinct from one another.

Thus, our collection of implicit social knowledge, what many people would call stereotypes but what are simply averages of our experience, end up being extremely useful to us. At an unconscious level, these averages give us the fodder for our “self-socialization” — our maturation into socially functioning individuals.

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As we begin developing our categories by averaging out a large amount of information collected by our social intelligence systems, we become eager to figure out which categories we’re in and begin acting appropriately to become a part of that group. The term “peer pressure” is a misnomer — peers needn’t pressure us at all for us to want to become a part of their group. (Harris shows in The Nurture Assumption that even a little girl who only sees other little girls from afar, and does not interact with them, will start acting as they do in hopes of becoming more “little girl-ish.”)

Other species are capable of averaging out information about groups and creating categories, but humans have a unique problem: We all belong to many different categories. We touched on this above — we are at turns many different things — boy, male, student, child, etc. We must learn to navigate each of them uniquely, and we do:

Self-categorizations are exquisitely sensitive to social context and can change at the drop of a hat. Girls and boys in a school lunchroom or playground ordinarily categorize themselves as girls and boys, but the presence of a mean or bossy teacher can cause them to unite in a common cause and to classify themselves simply as children. After the terrorist attacks of September 11, 2011, Democrats and Republicans classified themselves, for a while, simply as Americans.

As that last example illustrates, humans can identify even with groups (such as Democrats and Republicans) composed chiefly of strangers. They can identify with groups even if they don’t know who is in them. The social psychologist Henri Tajfel told some boys, supposedly on the basis of a test, that they were “overestimators” and others that they were “underestimators.” That’s all it took to evoke what Tajfel called “groupness” in the boys. When they were given the opportunity to award monetary payments to other members of the overestimator and underestimator groups (identified by group but not by name), they not only awarded more of the members of their own group: they also made sure to underpay the members of the other group. The boys who participated in this study all went to the same school, but none of them knew which of their classmates were overestimators and which were underestimators. There was no opportunity for the relationship system to put in its two cents.

Social categorization operates independently of the relationship system, just as the system for generating the past tense of a regular verb acts independently of the system for retrieving the past tense of an irregular verb.

As a group-adapted species, like chimpanzees or ants, humans must successfully figure out how to “get along,” and evolution has given us the automatic ability to do so. That’s why the vast majority of people end up similar to the people they grew up around: Those are the people we had to become similar to in order to socialize successfully. As we grow up, we acquire the customs, habits, language, accent, types of goals and aspirations, and lots of other traits of the culture around us, and it continues on as we age, although less dramatically over time.

But of course, we aren’t all brainless zombies, mindlessly mimicking our friends and peers. Human beings are far more complex than that, and this is why we all turn out differently, besides our differing genetics.

The socialization system explains why we become similar to those around us. What explains why we remain quite different? Harris calls it the Status System, and it’s the final piece of the puzzle.

The Status System

The most speculative, and perhaps controversial, aspect of Harris’s theories might be her thoughts on how we compete for status within our self-identified groups. She believes, and the evidence she corrals does support, a theory that this competition for superiority is a major long-term modifier of human personality:

The purpose of this system is the baby’s Job 3: to compete successfully. I’m talking now about competition within the group, classic Darwinian competition. To compete with one’s groupmates is to strive for status; the goal is to be better than one’s groupmates. “Humans everywhere pursue status.” observed the evolutionary psychologist Donald Symons, and for good Darwinian reasons: higher-status individuals have access to more of the world’s goodies.

But in humans, striving for status is a complicated matter. There are no straightforward rules for how to go about it; no single set of tactics is going to work for everyone. The status system’s assignment is to work out a long-term strategy of behavior that is tailor-made for the individual in whose head it resides. 

Mental organs are specialized collectors of data; each is tuned to respond selectively to certain kinds of cues. The relationship system and the socialization system both collect information about other people. The status system has a more difficult job: it specializes in collecting information about the self. One of the important things that children have to learn while they are growing up is what sort of people they are. Are they big or small, strong or weak, pretty or plain? Without this information they would have no basis for deciding whether to try to dominate others or yield without a fight, to make suggestions or follow the suggestions of others, to turn down potential mates in hopes of doing better or take whatever comes along.

During childhood and adolescence, young humans collect information on how they compare with the others who will be their rivals in adulthood. Armed with this information, they make long-term modifications in their behavior. It is the status system that enables them to do this.

Again, these systems are often at odds with each other. We can, at the same time, feel well-accepted by a group in general and feel we have little status within it, and those things may affect us in different ways. A bully who has little group acceptance can nonetheless have perfectly healthy self-esteem due to their status.

We develop our sense of self slowly over a very long gestation period. We figure out if we’re strong compared to most, smart compared to most, funny, quick, good-looking, suave, tall, or svelte, or perhaps the reverse. And we begin tailoring our behavior in a way that plays to our strengths, as a way to compete successfully for attention and status.

One economic study explored the idea, for example, that height had an impact on income for adult males. But once the economists sussed it all out, they figured out that it wasn’t simply tall adults who were better paid: What mattered was their height when they were adolescents. If you became tall late, you weren’t making more money than average.

Cross referencing this with another study on adolescent height and personality traits, Harris figures that because height (and other related traits like strength and athleticism) generally affords some status when you’re young, they can have long-term effects on your personality, including self-assurance and leadership ability. As it is with height, so it goes with other traits — height and income are simply the easiest to measure.

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So as we collect information about other specific people and other types of people to feed into our first two engines, the Relationship System and the Socialization System, we also collect information on the way we’re seen by the “generalized other,” which goes into System 3: the Status System. The use of that system enables us to design a personality that fits our particular situation.

This talk of “design” makes it sound more deliberate than it really is. All of this is happening with very little input from the “Head Honcho” upstairs. We can involve our slower, more deliberate “System 2” in the process, but the effect is dwarfed by what’s happening on its own.

Here’s how Harris thinks this whole Status System thing works its magic:

The status system, designed to collect and store information about the self, makes clever use of the features of the relationship system (the system designed to collect information about other people). The activities of the two systems dovetail like this: while your relationship system is gathering information about me and storing it on the page assigned to me in your people-information lexicon, my status system is trying to figure out what you’ve got recorded on that page. You keep the information you’ve learned about me separate–you don’t mix it together with information about other people–but I take that information I’ve gotten about myself from my page in your lexicon and put it together with similar information I’ve gotten from other people’s lexicons. What I need is a picture of myself from the point of view of the “generalized other.”

[…]

Unfortunately, this system doesn’t work perfectly–the picture is blurry…The reason we can’t read the page as accurately as we would like (or as accurately as we think we would like) is that the mind in which that page resides doesn’t want us to. It is to my advantage to know that you are thinking about me, but it may be to your advantage to keep me from knowing it.

The picture may be blurry but it’s nuanced and multidimensional. The status system uses this information to work out a long-term strategy of behavior tailored specifically for its owner. Using data collected in childhood and adolesence–How many people can beat me up? How often do other people look at me? Do people trust me to give good advice? — the system shapes and modifies personality in a way that takes account of the individual’s preexisting characteristics and the opportunities afforded by the environment.

From an evolutionary standpoint, this tendency for experience to modify long-term behavioral patterns, the tendency to use the self-knowledge obtained through the “mind-reading mechanism,” has increased the behavioral diversity among humans within our groups. While we do indeed seek to be part of a group, and will sacrifice for the success of that group, we also have deep self-interest. (Some of the most interesting worldly results come when those things are at odds with one another; see suicide bombers and kamikaze warriors.)

This drive to compete successfully and specialize as individuals makes us extremely well suited to live in large groups, something our species does uniquely well. In fact, Harris believes the modification of personality by way of social experience to be a unique human trait.

Denouement

So that’s it. As human beings develop, they collect vast amounts of social information and use it to form specific relationships and understand the specific details of the people around them, but also average out that information to create categories and groups, and to understand how to act to become part of the groups we think we belong in. We also seek to pursue our self-interest and, by figuring out what other people think about us relative to what they think about everyone else, we select strategies that we think will help us get ahead relative to the other members of our group or category.

The answer to the nature/nurture question is, of course, that both are hugely influential. Our genetics provide the blueprint by which we will interact with the world, and from there the specific course of our interactions and experiences with other people will determine how we turn out.

Harris admits that her theory needs rigorous testing to figure out whether she’s nailed it exactly or more refinement is needed. She suspects the latter will be true. As we dig into the details over time, we’ll figure out more specifically how these systems work and interact, where the lines blur between them, and how their relative effects take a toll on our long-term personality.

Regardless of the work that remains to be done, Harris’s work provides us with tremendous insight into what makes us who we are.

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Still Interested? It’s highly recommended that you read both of her books in full: The Nurture Assumption and No Two Alike.