Sex, Murder, and the Meaning of Life (14 page)

Psychologist Lisa DeBruine approached the question in a different way. She used computer morphing software to make a stranger look like a relative (by blending an image of a subject's face with an image of an opposite-sexed stranger's face). She found that people judged the faces with artificial kinship cues as “trustworthy, but not lustworthy.” That is, making another face resemble yours increases the odds that you will see this person as someone on whom you can depend but not as someone you would desire for a short-term sexual liaison.

At one level, people ought to be especially attracted to their close relatives (who otherwise meet many of the criteria for desirable mates, such as being very similar and very familiar). Why does the very thought disgust people? From a genetic perspective, it is as close to cloning ourselves as we could get. At first blush, it seems as if anything approximating cloning would serve a gene's interests (by maximizing the genetic overlap between parent and offspring). But something gets lost with too much togetherness. One key advantage of sexual reproduction is that it shuffles our genes with another set, which helps keep ahead of all those rapidly evolving viral and bacterial parasites. Besides insufficient shuffling, mating with firstdegree relatives results in what animal breeders call “inbreeding depression.” What that means, biologically speaking, is an increased chance of combining rare recessive genes that underlie harmful genetic disorders.

What happened when people thought about sex with friends threw us another interesting conceptual curveball. Men thinking about sex with their friends responded as they had to thinking about sex with strangers: Their positive feelings strongly outweighed their negative feelings. Women, on the other hand, reported slightly more negative than positive feelings, with disgust the most prominent
reaction. To raise this to a higher intellectual plane, if the
Friends
television characters Joey and Monica were to imagine having sex with one another, our results suggest that the thought might be appealing to Joey but slightly disgusting to Monica.

These results suggest two things. First, our brains do not operate according to one simple rule when it comes to thinking about people we regard as “attractive” or “likable.” Both men and women keep kin in a separate mental category from attractive strangers. Second, when thinking about friends, men and women do not use the same decision rules. In some ways, women treat friends like kin, whereas men treat them like strangers. But even that is an oversimplification. Although men often compete with male friends and feel sexual attraction toward female friends, they do not use the same rules for sharing rewards with friends as with strangers, and they are more likely to trust friends than strangers. And women are not nearly as disgusted by thoughts of sex with friends as they are by thoughts of sex with relatives. In other words, our brains use separate accounting systems for relatives, friends, and strangers.

Evolutionary theorists make a key theoretical distinction between kin and nonrelated friends. Because relatives share a higher percentage of identical genes with one another, anything we do to benefit a relative's reproductive success indirectly benefits our own fitness. The technical term that evolutionary biologists use is “inclusive fitness”—which refers broadly to an individual's success at passing his or her genes on. My contributions to my son's reproductive success count toward my own, as would anything I might do to help my sisters. Inclusive fitness helps explain why I was a lot more tolerant of my son's European-vacation teenage whining than my ex-wife was (she was not his mother).

Helping between friends, on the other hand, is typically explained in terms of reciprocal altruism—helping that continues as long as you keep scratching my back at about the same rate as I scratch yours. Reciprocal
altruism is a powerful rule: It allows humans in groups to accomplish many things they could not accomplish alone, and when times are tough, it may mean the difference between survival and starvation. But it works on a slightly different math than inclusive fitness. Every time I give something to my son I give something to my own genes; that bond is always there. The same does not hold for my friend Rich. If he and I stop getting rewards from our mutual interactions, as we did during our ill-fated European vacation, the bond can be threatened. Although Rich and I had a long enough history of mutual reward that we were able to get over a few bumpy weeks, some relationships end forever when former friends calculate an unfavorable answer to the question, “What's in it for
moi
?” As for the French bakerwoman who was rude to me for a couple of minutes, she and I had neither type of bond going, so when our short relationship started so negatively, it cost me nothing to move her over into the “enemy” category.

In the first psychology textbook ever written, William James suggested that “a man . . . has as many social selves as there are distinct groups of persons about whose opinion he cares.” James's suggestion fits with the research I just discussed—perhaps we have different functional subselves for dealing with different categories of people: relatives, friends, potential mates, romantic partners, ingroup acquaintances, and enemies. That model beats the alternative view that we have only one single tightly integrated self, but it has a key limitation. Sometimes the same other person can be a friend, a competitor, or a sexual opportunity, depending on other factors in the current situation.

I think we get a better answer to the question, “How many subselves?” if we first ask another: “What are the key sets of problems
human beings typically have had to solve?” That would suggest a different subself for dealing with qualitatively different situations: dangers of violence, disease, or losing romantic partners; or chances to find new mates, gain status, establish friendships, or provide for our close relatives.

The idea of functional subselves has guided my team's research on what we call “fundamental motives.” When you are under the influence of a different fundamental motive, such as mating or self-protection, you are a different person—you notice different things and you remember different things, and that leads you to respond differently to the same situation. I have already talked about how activating different motivational subselves linked to mating, self-protection, or disease avoidance can lead to different patterns of prejudice and to different responses to a member of the opposite sex. In the next few chapters, I will talk more about how the different biases associated with each of these subselves can influence our inclinations to spend money on flashy goods, to conform to group opinion, or to want to go to church.

Here is a list of the separate characters that I think you and I have running around inside our heads, and what set of problems or opportunities each of those subselves is in charge of managing:

At any given moment of consciousness, only one of these subselves is running the show. When you are worried about the band of knife-wielding thugs who just walked around the corner, you are not thinking about romancing your date. Some of your subselves have common goals—befriending a neighbor could simultaneously serve affiliative, self-protective, and parenting goals, for example. But some of them have incompatible goals—your swinging-single subself and your good spouse subself being the most obvious example.

These different subselves, in some sense, serve as the packages for the modules I was discussing earlier. The data on homosexual men's choices, for example, suggest a lot of separate mental switches linked to the mating motive, not just one. Or, to take another example, if you trigger a mechanism designed to recognize an angry face, it activates another set of linked mechanisms involving self-protection. That said, most of our mental modules are not rigidly encapsulated—that is, they share some software and hardware—as when women treat kin and friends using many of the same decision mechanisms. In this sense, your mind is very much like a computer: It has different named programs on it, but all of them rely on the same hardware for inputs and processing and use much of the same core code of the operating system to get their tasks done.

In the next chapter I will describe how different subselves come on line at different stages of our lives, and in Chapter 8 I will talk about how our mental processes change radically depending on which of our different subselves is currently in charge.

Thinking about subselves helps me understand why things were so stressful on my European vacation. It is easier to make decisions when there is only one subself in the driver's seat. At any given moment, in fact, there can be only one driver—my body can only walk in one
direction and my conscious mind can only think about a limited amount of information. During the portion of the vacation when I was biking alone with my son, my parental subself got to drive for most of the day, and it was a lot less exhausting. If I had been traveling alone with my friend Rich, then my affiliative subself would have been in the driver's seat, and it would have gone more easily. In fact, Rich and I took a trip to Mexico a decade later, without our families, and it was quite pleasant. Likewise for travel with Melanie; she and I traveled to Italy alone on another junket and it went splendidly. But when we were all together, and my parent subself was pitted against my spouse subself and my affiliative subself was pushing in another direction, it got exhausting. And to make matters worse, my slightly paranoid night watchman subself is often on alert when I am traveling, ever attentive to the possibility that the next stranger could be a thief, a pickpocket, a mugger, a terrorist, or—worse yet—a French bakerwoman.

I
t's 1967, and I have a summer job working 4:00 p.m. to midnight as a doorman at the Paramount Hotel in New York's theater district. On a typical night, I go through all the steps in Abraham Maslow's famous pyramid of motives. By dinner break, I've been carrying luggage and chasing down cabs for several hours, and I'm starving and thirsty. So I order a couple of slices of pizza and a chocolate malt from the Greek joint around the corner, to the sound of the Young Rascals' “Groovin'” on the radio back in the kitchen. Returning from my meal, I worry about my physical safety as I pass a nasty looking junkie on Eighth Avenue. Safe and sound back at the hotel, I strike up a friendly conversation with a college student from Georgia who is visiting New York for the first time. After nine or ten in the evening, business slows down, and I get to finish off my shift reading psychology books, as I dream about someday becoming a university professor and fulfilling myself as an intellectual.

It was during my doorman period that I first came across Maslow's pyramid (
Figure 7.1
). Maslow's powerful visual image of a pyramid of needs has been one of the most cognitively contagious ideas in the behavioral sciences, so you've seen this picture if you've ever taken a
course in psychology or organizational behavior. Maslow was spurred to develop his model of human motivation because he disagreed with the prevailing paradigm in psychology at the time. As I discussed in Chapter 6, behaviorists—who dominated psychology in Maslow's day—tended to believe that all human motives could ultimately be traced back to a few “primary drives” such as hunger and thirst. On that view, my young son seeks contact with his mother because he has learned to associate that contact with a primary reward—food. Psychologists at the time likewise viewed adults' desires for love, respect, and intellectual fulfillment as “secondary drives”—desires rooted in past experiences involving their parents rewarding them with milk and cookies when they acted affectionately, hit a home run, or got a good grade in school.