As we explained in the previous chapter, there are six broad categories of personality characteristics—the HEXACO personality factors. This means that we could summarize someone’s personality rather well by assessing his or her level on each of those six dimensions.
But this leads to the same kinds of questions that we used to ask ourselves about the Big Five. What do these personality factors mean? And why should these factors be the basic dimensions of personality? In this chapter, we’ll try to answer these questions. We’ll start by describing in more detail the characteristics of people who have higher or lower levels of each of the six HEXACO personality factors. Then, for each of those six dimensions, we’ll discuss the advantages and disadvantages of having a higher or lower level, both in modern life and in the human evolutionary past.
Table 3–1 shows general descriptions of each of the six factors. For each factor, the left and right sides of the page show the characteristics of people who have very high levels and very low levels, respectively, of that factor. Keep in mind that each of these factors is a dimension—a continuum. For the sake of simplicity, we describe people as being “high” or “low” on a given dimension, but don’t take this to mean that people come in two distinct groups. Instead, most people are somewhere in between, with relatively few people at very high or very low levels. In fact, the distribution of people’s levels on each factor is fairly close to what statisticians call the normal distribution—the familiar bell-shaped curve (see Figure 3-1).
TABLE 3–1 Descriptions of Persons with High and Low Levels of the HEXACO Factors
Honesty-Humility (H) |
|
High |
Low |
• avoid manipulating others or being false |
• flatter others, pretend to like them |
• scrupulously fair, law-abiding |
• willing to bend rules for personal gain |
• wealth and luxury not so important |
• want money and expensive possessions |
• don’t consider themselves superior |
• feel entitled to special status and privilege |
Emotionality (E) |
|
High |
Low |
• fearful of physical harm |
• not deterred by physical danger or pain |
• worry about minor matters |
• little anxiety even in stressful situations |
• like to share concerns with others |
• don’t need emotional support from others |
• feel empathic concern towards others |
• little sentimental attachment to others |
eXtraversion (X) |
|
High |
Low |
• see positive qualities in self |
• consider self to be unpopular |
• confident leading, speaking in groups |
• feel enthusiastic and upbeat |
• enjoy social interactions |
• avoid small talk, prefer to be alone |
• feel uncomfortable with attention |
• don’t feel lively or dynamic |
Agreeableness (A) |
|
High |
Low |
• do not hold grudges, not resentful |
• find it hard to forgive |
• lenient in judging others |
• critical of others’ shortcomings |
• flexible in opinions, accommodating |
• stubborn in defending point of view |
• patient and even-tempered |
• feel anger readily when provoked |
High |
Low |
• orderly with things and time |
• disorganized surroundings and schedules |
• work hard to achieve goals |
• avoid difficult tasks or challenging goals |
• pursue accuracy and perfection |
• don’t mind incompleteness, inaccuracy |
• prudent, careful decision making |
• act without thinking of consequences |
Openness to Experience (O) |
|
High |
Low |
• appreciate beauty in art and nature • intellectually curious • use imagination in everyday life • like to hear unusual opinions |
• indifferent to artistic and aesthetic pursuits |
• uninterested in natural or social sciences |
|
• avoid creative activities • not receptive to unconventional ideas |
|
One way to understand the HEXACO dimensions is to consider each as a contrast between two opposite strategies for interacting with one’s surroundings. By “strategies” we don’t mean conscious or calculated choices. (You could think of tall and short as two contrasting strategies of height, but this wouldn’t imply that people choose their own height.) What we mean is that opposite poles of a personality dimension represent opposite ways of dealing with some aspect of life. There are some times and places in which people having the “high” pole of a dimension would be better suited to their environment; in other times and places, the low pole would be better. If instead the high pole of a given dimension was always better than the low pole, or vice versa, then pretty much everyone would have about the same level of that dimension—there wouldn’t be much variation in that aspect of personality.1
Below, we’ll be interpreting each of the six HEXACO trait categories as a contrast between two strategies—two opposite ways of dealing with some important feature of life. For each of the six, we’ll consider the pros and cons of having high or low levels of the dimension. In describing these trade-offs, we’ll consider the consequences of the dimensions in modern life: researchers have examined the links between personality and outcomes in various aspects of life, such as career, relationships, and health. But we’ll also speculate about how personality dimensions would have mattered before the modern era, both in the recent (historic) and the distant (prehistoric) past.
FIGURE 3–1 The Normal Distribution
First, consider the O, C, and X factors. Look in Table 3–1 at the descriptions of high and low scorers on each of these three dimensions, and ask yourself this question in each case: Which side of the factor seems “busier”—which one implies more activity or engagement of some kind? We think you’ll agree that for all three factors, it’s the high side. For O, C, and X, persons with a higher level of the dimension tend to be more actively engaged in a certain area of endeavour than are persons with lower levels. What makes the three trait categories different from one another is that each involves a different kind of endeavour.
To start, let’s consider the Openness to Experience traits. The common element of the high-O traits is the tendency to engage in idea-related endeavours: high-O people become deeply absorbed in contemplation of art and nature. They want to understand the human and natural world. They generate new ideas and look for new solutions to old problems. They’re receptive to ways and customs that seem unfamiliar and strange.
This engagement with ideas means that high-O people tend to learn, discover, and create a lot more than low-O people do. In modern society, people who are high in O tend to acquire a wide general knowledge and a large vocabulary. They like to travel widely, exploring new physical and cultural environments. They pursue occupations that demand creativity, whether as an artist or as a researcher.2
A high level of O would have provided some advantages in the human evolutionary past. Other things being equal, a person who learned more about other peoples and languages, about different natural environments, and about new tools and skills would have had a better chance of gaining the resources needed to survive and reproduce. But being high in O would also have had some drawbacks. One is risk of physical harm: high-O activities such as exploring new lands, trying new ways of doing things, or expressing unusual opinions all carry some dangers.3 Another potential drawback is the energetic cost of doing these high-O activities and even of being switched on all the time—of continually thinking and imagining. (The brain accounts for about 2% of an adult human’s body weight but about 16% of the body’s energy consumption.)4
Now let’s turn to the Conscientiousness traits. The common element of these characteristics is the tendency to engage in task-related endeavours. High-C people organize their time and their physical surroundings. They work hard and long. They pay thorough attention to details. They think through their options systematically and carefully.
High-C persons can gain some important benefits from their task-related engagement. This is evident in several ways in modern life. People high in C tend to perform better in school and on the job than people low in C. Because they are able to inhibit their impulses, high-C people are less likely to smoke, use drugs, or drink excessively. They are also less likely to be involved in serious accidents, and much less likely to lose their money by gambling or spending recklessly. Consequently, high-C people tend to be better off financially and tend to live longer and healthier lives than low-C people do.5
In pre-modern times, the work ethic and foresight of high-C persons would have meant a larger and more consistent food supply and better capacity to deal with various disasters. These benefits would have been greatest in environments where working and planning had the potential to generate benefits. But if instead there had been little chance to get more food or prevent disasters, then high C would have been less advantageous.
The main disadvantage of high C is probably its energetic cost. People who do more physical work will require more energy to fuel their bodies, and people who make the mental effort of planning and inhibiting impulses will require more energy to fuel their brains. (Interestingly, there is some evidence that acts of self-discipline do deplete the brain’s reserves of glucose.)6 In pre-modern times, when food supplies were less secure than they are today, these energy costs might actually have outweighed the benefits, especially if one lived in an environment where hard work and planning did not always pay off.7
Next let’s consider the eXtraversion traits. Here the common element is the tendency to engage in social endeavours: high-X people assume that other people like them.8 They’re comfortable stating opinions and leading others. They like to make friends and to interact frequently with them. They exude a cheerful enthusiasm.
The social engagement of high-X persons tends to make them desirable partners for all kinds of interactions. In modern settings, high-X people tend to be the most popular members of their peer group, be it a college dormitory, a social club, or a workplace. They’re also more likely to become leaders of such groups. And they’re generally seen as physically attractive and hence as more sexually desirable.9
In the human evolutionary past, people high in X would generally have had more friends, allies, and mates—and a better choice of friends, allies, and mates. This network of social resources could have improved a person’s odds of surviving and reproducing. But one downside of high X is that it probably carries some important energetic costs, if people who maintain a lively, upbeat state consume more energy than those who are more passive. Another disadvantage is that people who attract positive social attention likely also attract competitive hostility from those who covet that positive attention. This can translate into some risks of physical harm.10
According to our interpretations above, you can probably imagine what would be the personality of someone who combines high levels of all three of O, C, and X. Such a person will come across as highly engaged and “switched on”; in contrast, a person low in all three factors will seem rather inert. But because the O, C, and X factors are uncorrelated with one another, few people are very high in all three or very low in all three.
Now let’s turn to the H, A, and E factors (see Table 3–1). Unlike the situation for O, C, and X, there’s no clear tendency for either pole of H, A, or E to be busier or more engaged than the other. Instead, H, A, and E each involve a contrast between an “altruistic” tendency (at the high pole) and an “antagonistic” tendency (at the low pole). But these three factors relate to altruism and antagonism in different ways.
First, the Honesty-Humility factor: high-H traits share a common element of not exploiting others. People high in H avoid manipulating or deceiving people. They don’t cheat others or steal from them. They don’t feel entitled to take advantage of people, nor do they particularly want to have more than other people do.11
This reluctance to exploit others shows itself in various ways. High-H people are much less likely to commit crimes of various sorts. They generally give others their fair share even when they could get away with not doing so, and even when the others are strangers. They are much more likely to favour ethics over profit and much less likely to be sexually unfaithful or sexually exploitive. (We’ll discuss all of the above in more detail in Chapter 9.)
An important benefit of being high in H is that by treating people fairly, one can gain the benefits of future cooperation with others. In other words, when you don’t take advantage of others, people generally come to trust and cooperate with you. The cooperation of others can make a more satisfying life in modern society, but in many pre-modern settings this “bank account” of cooperation could be crucial for improving the odds of surviving and reproducing. The low-H person, by contrast, undermines the goodwill of others, thereby losing their cooperation and even provoking their active retaliation.12
The cost of being high in H is obvious enough. If your conscience simply won’t permit you to exploit others, you miss many opportunities for personal gain—opportunities where there is little chance of suffering negative consequences. The high-H person doesn’t exploit others even when there is no chance of being detected and even when the potential victims are powerless to retaliate.
Next, the Agreeableness factor: the common element of high-A traits is a tendency to get along with others even when they may be hard to get along with. High-A people forgive past injustices rather readily. They’re lenient in their judgments of others. They’re flexible in letting people have things their own way. They’re slow to get angry even when provoked.
This tendency to be tolerant and patient has some interesting consequences. High-A people generally report being happier with their marriages—and so do the spouses of high-A people. They also have a lower risk of developing coronary heart disease as well as a better chance of recovery from it.13
The main benefit of high A—whether in modern life or throughout the evolutionary past—is that it maintains the benefits of cooperation. In many cases, a person who seems to be treating you badly actually turns out to be a rather nice person. If you have the high-A tendency to continue (or resume) cooperating, you won’t miss out on the gains of ongoing future cooperation with that person. But the disadvantage of being high in A is that it also allows you to continue cooperating with people who truly are trying to exploit you.15
BOX 3–1 Herding, Farming, and the Optimal Level of A
Here is a possible example of how the optimal level of A could depend on the relative benefits of cooperation and costs of being exploited. Consider the contrast between a herding society (based on livestock) and a farming society (based on crops). Livestock such as sheep and cattle are very mobile, so it’s easy for rustlers to round them up and drive them away; to deter this potentially disastrous kind of exploitation, herding societies favour lower levels of A. In contrast, low A is less advantageous in a farming society: it’s much harder for a would-be thief to harvest a field of crops and carry them away, and there may also be more opportunities for cooperation (think of the old-fashioned barn-raising bees). Some researchers have used the contrast between herding and farming societies to explain the differences between the cultures of White settlers in the southern and northern United States: the South, whose upland areas were settled mainly by herders, has been known for its “culture of honour,” in which minor insults can spark feuds.14
The H and A factors thus represent two distinct aspects of the tendency to be cooperative: high-H people cooperate with you even when they could get away with exploiting you; high-A people cooperate with you even when you are not really cooperating fully with them. Low-H people undermine cooperation by taking unfair advantage of you, and low-A people undermine cooperation by being too quick to decide that you’re taking advantage of them.
Finally, the Emotionality factor: the common element of the E traits is that they promote the survival of oneself and one’s kin. People high in E avoid physical dangers. They worry about potential harms both to themselves and to their families. They seek help and support in times of need. They feel strong empathy and attachment toward their family and close friends.
The self- and kin-preservation associated with the E factor shows up in several ways. For example, very high-E people are at risk for what psychologists call “separation anxiety disorder.”16 Although this disorder is usually diagnosed in children, it occurs in adults too: some adults dread being apart for even one night from their spouse or child and worry obsessively about unlikely harms that might befall those persons, such as a freak accident or a kidnapping. High-E persons are also more likely to develop phobias—that is, excessively strong fears of physical dangers, such as animals, blood and injections, collisions and falls, and closed spaces.17 Conversely, very low-E people can have the opposite problems: some of them are indifferent to family ties and incapable of romantic love. Some of them suffer injury or even death because—being undeterred by the prospect of physical harm and pain—they expose themselves to great dangers both at work and at play.
The benefit of high E is therefore the reduced likelihood that serious harm will befall oneself and one’s kin. The cost, however, is that high-E persons (and their kin) forgo the potential gains from activities that carry risks to the well-being of oneself or one’s kin. In the human evolutionary past, the ideal level of E would have depended on the local environment. For example, if the only way to make a living was to carry out some dangerous task, lower E would have been better. Or, if there were many avoidable dangers to oneself and one’s offspring, higher E would have been better.
The relative value of higher versus lower E also depends on one’s sex. Throughout the human past, the survival of a child depended more on its mother’s survival than on its father’s.18 And for a woman, the heavy biological cost of pregnancy and lactation means that having another child is a much more difficult proposition than it is for a man. (Moreover, a woman rarely has any doubts about which children are her own and which children aren’t, whereas a man has less certainty on both counts.) Consistent with these facts, the average level of E is consistently higher for women than for men. This difference is not huge—there’s a lot of overlap between the sexes in their levels of E, about as much as there is for height—but it’s found reliably across cultures as different as the United States and Turkey, or Korea and the Netherlands.
As we mentioned earlier, the E factor promotes strong feelings of empathic concern and emotional attachment, which in turn promote altruism (and inhibit aggression) toward one’s kin. In short, high-E people have a strong inclination toward kin altruism. Now, suppose that an individual has not only a high level of E but also high levels of both H and A—the ingredients of cooperation, or reciprocal altruism. Such a person will be highly altruistic all-around—basically, a very nice person. Conversely, a person low in E, H, and A will be highly antagonistic—a very nasty person.
BOX 3–2 Personality and Altruism: H as the Missing Link
When we noticed the H factor in studies of personality trait words, we finally understood the answer to a problem that had nagged at us for several years. Back in 1996, when we started working together, we were trying to understand the Big Five Agreeableness and Emotional Stability factors in terms of what biologists call “kin altruism” (i.e., a tendency to be protective and solicitous of your family members and other people who are like family) and “reciprocal altruism” (i.e., a tendency to cooperate with others in general). Basically, we believed that “sentimental” traits (such as empathy and emotional attachment) should promote kin altruistic behaviour, whereas “patient” traits (such as tolerance and even temper) should promote reciprocally altruistic behaviour.
When the studies of various languages showed that sentimental traits and patient traits formed neat factors of their own—the E and A factors, respectively—this made perfect sense to us. But the finding of an H factor solved an even bigger problem. Back when we were developing our ideas about personality traits in relation to kin altruism and reciprocal altruism, we realized that something was missing. According to theoretical biology, “reciprocal altruism” should involve two quite distinct kinds of traits. Being a tolerant, patient person makes you a good partner for cooperation, because you aren’t always getting unduly angry at other people. At the same time, being an honest, fair-minded person also makes you a good partner for cooperation, because you aren’t always trying to cheat other people.
These latter tendencies didn’t have a place of their own in the Big Five model. But when the sixth factor was found, everything fell neatly into line: there was one factor for traits that promote kin altruism (E), one factor for the “patient” kind of reciprocal altruism (A), and one factor for the “fair” kind of reciprocal altruism (H).
As we mentioned above, people who are high in all three of these factors are very nice people. This can also be seen in the results of lexical studies of personality structure, for traits that describe an overall “nice” tendency—for example, sympathetic or soft-hearted—tend to fall partly in the E trait category, partly in the H trait category, and partly in the A trait category.
In this chapter, we’ve tried to explain the meaning of the HEXACO personality factors—why these six dimensions are important, and why people differ so widely in these aspects of personality. We’ve argued that each dimension can be seen in terms of two opposing strategies for dealing with one’s surroundings: depending on where and when a person is living, a higher level of a given dimension may work better than a lower level, or vice versa.
So far, however, we’ve considered each personality factor in isolation from the others. In the next chapter, we’ll explore the personalities of people who exhibit various combinations of the personality dimensions. We’ll be focusing on people who have low levels of the H factor in combination with high or low levels of the other five dimensions.
But before you read about these varieties of low-H people, you might be interested in a couple of fundamental questions about personality: Do people have different personalities because of the genes they inherit or because of environments they experience? And how much do people’s personalities change throughout their lives? We examine these questions in Box 3–3 and Box 3–4.
Suppose that we take a large group of adults from any modern, developed country. These adults grew up in families that differed widely in their levels of income, education, and religiosity, and in their styles of raising children. But these adults still have much in common: they’re all from the same ethnic group and the same generation, and they all went to similar schools and grew up in broadly similar communities. None of them experienced any really severe abuse or neglect when growing up, and none of them were desperately poor.
The adults of this group will show the full variety of personalities. For any of the six personality dimensions, some will be very high, others very low, and most somewhere in between.
But why are they so different in personality? Is it mainly because of nature—differences in the genes they inherited? Or is it mainly because of nurture—differences in the families and households they grew up in? The answer is one of the most striking discoveries of personality psychology: genes are heavily involved in personality differences, rearing environments hardly at all.
How do we know? Researchers have figured this out by measuring the personalities of various kinds of relatives, to find out how similar those different kinds of relatives typically are. For example, suppose we measure many pairs of identical twins (who share 100% of their genes—they’re genetically identical). And suppose we do the same with many pairs of fraternal twins (who share 50% of their genes—the same as for regular, non-twin siblings). If identical twins tend to be more similar to each other in personality than are fraternal twins, this suggests that heredity (nature) has an influence on personality. (Here we’re talking about the genes that actually differ from one person to the next. We’re ignoring all of the genes—the vast majority—that are identical for all human beings.)
As another example, suppose that we measure many pairs of biological siblings who were raised together (the usual situation). And suppose we do the same with many pairs of biological siblings who were raised apart (perhaps due to adoption or divorce). If the siblings raised together tend to be more similar to each other in personality, this suggests that the rearing environment (nurture) has an influence on personality.
For one last example, suppose that we measure many pairs of siblings who are biologically unrelated (as happens when a family adopts one or more children). If these siblings tend to be at all similar in personality, this suggests that the rearing environment is also involved.
When researchers do these kinds of studies, here’s what they find:19
• On average, identical twins are very similar in personality, and about twice as similar as fraternal twins.
• On average, biological siblings are only modestly similar in personality, but it doesn’t matter if they were raised together or apart.
• On average, adoptive relatives aren’t similar at all in personality—no more than any other biologically unrelated people.
All of this tells us that differences in people’s genes do contribute to differences in their personalities and that differences in their rearing environments do not. The best recent estimates are that personality differences are about two-thirds due to genetic differences and almost not at all due to differences in early household environment. This means that if two people have identical genes, they’ll likely have rather similar personalities even if they’re raised in different households. Also, if two people have entirely different genes, they’ll have quite different personalities even if they’re raised in the same household. Keep in mind, though, that these studies probably include very few people who had been severely abused or neglected as children. If there were many such people in the research samples, the results might well show some effects of the rearing environment.20
By the way, these findings don’t mean that there must be one specific gene, or even a few specific genes, that cause people to have higher or lower levels of any given personality factor. Research thus far suggests that personality differences are caused by the combined effects of very many genes, each of which has only a small effect on its own. As for exactly how those genes influence personality—how they act through the workings of our brains—it will likely be a long time before researchers have much more than a superficial understanding.
But if personality differences between people are two-thirds due to genetic differences and not at all due to household environment differences, what about the other one-third of personality differences? Well, even though your personality as an adult probably doesn’t depend much on the household or family in which you were raised, it is possible that your experiences while growing up still had some effect. Researchers have suggested some early experiences that might influence adult personality:
• Peer, or friendship, groups during adolescence: people might become more similar to their friends in some aspects of personality (thereby fitting in with their peers), or they might become more distinct from their friends in other aspects (thereby being unique among their peers).21
• Birth order—more specifically, a person’s age rank among the siblings raised in his or her family: for example, it has been suggested that later-born children may be more rebellious than earlier-born children.22
Research studies conducted so far suggest that these effects are likely to be small,23 but taken together and in combination with various other influences, they should account for the one-third of personality variation that isn’t accounted for by genetic differences.
BOX 3–4 Does Personality Change?
The question of whether personality changes is actually two different questions. First, does the average person change in some predictable ways throughout his or her lifespan? And second, do people change in comparison with the average person of their own age group? To see the difference between these questions, consider athletic ability: obviously, the average adult becomes less athletic between age 20 and age 60, but this doesn’t mean that the most athletic 20-year-olds end up as the least athletic 60-year-olds.
To get a picture of how the typical person develops, researchers have measured people’s personalities at intervals of several years. Their findings show that most people become somewhat higher in the A, C, and H factors of personality between their teens and their forties. The difference isn’t large—in fact, there are many teenagers who have high levels of these factors, and many middle-agers who have low levels. But the trend is for people to be more responsible, better socialized citizens after young adulthood than they were before it.24
It isn’t yet clear why these changes happen. Perhaps as people progress through young adulthood, changes occur in their biological predisposition for these personality characteristics. Or perhaps the typical changes in life’s circumstances during young adulthood—career, marriage, children, homeowner-ship—simply bring out more of the behaviours associated with these aspects of personality.
Researchers have used the same data to get a picture of how people change in comparison with other people of their own age cohort. These data generally show that people’s personality trait levels—compared with the levels of other people from their own age cohort—are highly consistent even over many years. For any given personality trait, a person’s level at (say) 30 years old will very likely be similar to his or her level five decades later, when he or she is 80 years old. (This degree of consistency is somewhat lower during adolescence and young adulthood, when there is a bit more shifting in people’s levels of the major personality traits.)25 Although some people do show important changes in their personality trait levels, most people don’t.