The Folly of Fools: The Logic of Deceit and Self-Deception in Human Life

by Robert Trivers

  Homosexuality and HIV status also turn out to be especially useful in studying deceit and self-deception because each invites a form of denial that, unlike the experimental work, occurs almost daily over a long period of time. Homosexual men often differ in the number of people to whom they reveal their sexual identity (degree to which they are “out of the closet”)—from only a few heterosexual close friends, to those plus one’s family, to all of those plus one’s workmates, to the whole world. Likewise, it is possible to deny HIV-positive status to others and to attempt to deny it to self. All of these efforts bring negative immune and health effects, which may be substantial.

  Relative to HIV-positive men who are mostly or completely out of “the closet,” those who were at least half in the closet enjoyed 40 percent less time before they suffered from AIDS itself and 20 percent lower survival rate overall. Three separate studies show that denying one’s HIV-positive status to others or even to self (“I am not really sick”) is associated with lower immune function and/or more rapid progression of the eventually fatal HIV infection. In HIV-positive women, evidence of emotional support was not associated with immune change but evidence of psychological inhibition (use of inhibition words in daily speech) was associated—more inhibition, faster immune decay.

  One study of the progression of HIV in gay men as a function of the degree the men were in the closet also controlled for unprotected sex of the dangerous kind (anal receptive). Sure enough, those in the closet practiced more of this kind of sex (being in denial, they probably prepared less for the sex likely to occur later that night). This factor had a positive effect on the rate at which their HIV progressed (probably due to the addition of competing HIV strains), but independently, being in the closet was much more harmful for resistance to HIV. At least in this respect, truth appears to be healthy for the organism expressing it: your immune system is stronger, and at the same time you are more conscious—in this case, less likely to act in obviously self-destructive ways. The US government’s recent policy on service by homosexuals, “don’t ask, don’t tell,” is an immunological disaster. You are asked to deny your sexual identity, which will invite a host of unwanted and unnecessary immune problems for you, all in order to keep everyone else relaxed.

  Here is one vivid account of what it would be like to hide your heterosexual identity if this were required (as in the US military):Try never mentioning your spouse, your family, your home, your girlfriend or boyfriend to anyone you know or work with—just for one day. Take that photo off your desk at work, change the pronoun you use for your spouse to the opposite gender, guard everything you might say or do so that no one could know you’re straight, shut the door in your office if you have a personal conversation if it might come up. Try it. Now imagine doing it for a lifetime. It’s crippling; it warps your mind; it destroys your self-esteem. These men and women are voluntarily risking their lives to defend us. And we are demanding they live lives like this in order to do so.

  The ill effects of concealing one’s homosexual orientation are not limited to HIV-positive men. In a sample of twenty-two HIV-negative gay men studied for five years, those who concealed their homosexual identity were about two times as likely to suffer cancer and infectious diseases, such as bronchitis and sinusitis, as those who did not. These results are independent of a variety of potentially confounding factors such as age, socioeconomic status, drug use, exercise, anxiety, depression, and so on. What is especially striking is that for both cancer and infectious diseases, the effect is strictly dose-dependent—the more you are in the closet, the worse for you. Recent evidence suggests that disclosing homosexual orientation may bring correlating cardiovascular benefits as well.

  Not all homosexual men are alike, of course; some are more sensitive to rejection than are others and this can have important effects. Those who are more rejection-sensitive are more likely to remain in the closet, where they avoid rejection and benefit from this immunologically. Apparently there is a general cost to remaining in the closet, but a variable benefit when one is rejection-sensitive, and this benefit can overwhelm the cost.

  Have you heard of the latest twist in this saga? There are gay men who are said to be living in a glass closet. They project heterosexuality to their friends, because they believe they would be rejected if people knew about their homosexuality, but in fact the friends know about it and merely go along with the charade. It would be interesting to know where these men lie along the immune continuum. I would guess they are healthier than those in conventional closets, but not by much.

  POSITIVE AFFECT AND IMMUNE FUNCTION

  Direct experimental tests confirm a strong association between positive affect and immune function but are unclear regarding the correlates of negative affect. Challenging people who have never been exposed to hepatitis B with a hepatitis B vaccine shows a clear positive association between positive affect and a strong, positive immune response, no matter whether the measure of positive affect emphasizes calm, well-being, or vigor. Although negative affect has the opposite effect, this was not significant when corrected for positive affect. In general, it seems as if positive affect is not merely the absence of negative and vice versa. In some cases negative and positive affect act as independent variables and in others as only partly independent ones.

  The activity of neurotransmitters such as dopamine and serotonin provides a partial explanation. Dopamine shows a phasic spike in single neurons in response to the anticipation of a reward. If the reward equals expectation, the spikes continue apace; if it exceeds, the spikes increase in rate, and if it is less than anticipated, the spikes shrink to less than the spiking baseline rate for negative rewards. Positive affect increases both dopamine and serotonin production, but negative affect has no direct effect on dopamine (though it may indirectly do so via serotonin production). Dopamine modulates immune functioning and there is an asymmetry between positive and negative affect—positive having stronger effects than negative—both on cognitive and immune function. The deeper reason for this asymmetry remains unclear.

  Measures of positive affect are also associated with better survival in relatively healthy elderly people who are living independently in their communities, but curiously enough, positive affect appears to be associated with reduced survival among those already institutionalized. Likewise, those with terminal conditions, such as malignant melanoma and metastatic breast cancer, are worse off with positive affect, but in diseases with higher long-term survival, such as AIDS and non-metastatic breast cancer, positive affect is beneficial.

  A possible functional explanation for these anomalies comes again from considering the rate of reward necessary to maintain positive affect and positive immune function. If your body is deteriorating quickly and you feel bad because your illness is proceeding so fast, then the expected reward of positive dopamine spikes dies down rapidly, as do the dopamine spikes. This reduces the positive cognitive and immune benefits of enhanced dopamine production. If, on the other hand, a person is caught in a long-term degenerative condition, the rate of deterioration may be slow enough that dopamine spikes and positive affect are capable of generating the cycle of positive feedback necessary to sustain improved mental and immune function.

  THE EFFECTS OF MUSIC

  By choosing to listen to music, people can alter their mood and their immune system. Some of the music experiments are almost too good to be true. For example, Musak (bland, peaceful music designed to calm people in a claustrophobic situation, such as an elevator) produced an increase in output of an important immune chemical by 14 percent, while jazz did so by only 7 percent. No sound had no effect, and simple noise had a 20 percent negative effect. Melodic music may suggest a happy and harmonious structure to the immediate world, while noise is cacophonous and connotes disorder, uncertainty, even danger. Music composed to match the pitch and tempo of natural monkey (tamarin) sounds but not using the monkey sounds themselves induced behavioral changes in the lab in tamarins similar to those ob
served in our own species. Though tamarin music based on threat vocalizations induced more anxious activity, music based on positive social interactions had positive effects: less surveillance, less sociality, and more foraging—exactly what one finds in other animals when external threat is reduced. Almost certainly there were parallel immune changes, negative to threat and positive to warm affect, so that the human response to music must have a very long past.

  Two recent results stand out. Injecting about five hundred cancer cells into mice that have been stressed by exposure to noise at midnight results in much less cancerous growth if the mice then enjoy five hours of melodious music each morning. An equally dramatic example comes from humans. People undergoing bronchial physiotherapy (aspirating medicine, breathing, coughing) while listening to Bach’s music (in a major key) recover much more quickly than those enjoying the therapy without music. (Minor keys show neutral or negative effects.) The point is that the right kind of music can induce positive feelings that are in turn associated with positive immune and health effects.

  Certainly we know that female choice has forced a cognitive burden on males, the better to keep the females entertained. Song repertoire size in birds, which is favored by females, is controlled in males by a substantial set of neurons in the brain that completely regress during the nonbreeding season (clear evidence of the cost of running the show). We would expect pleasing male song to be both sexually arousing in females and immunologically positive. The same thing might be said for human courtship and for relations between a pair—surely there are many immunologically positive interactions possible on both sides, including good sex, and many negative ones, such as conflict, anger, suppressed feelings, and bad sex.

  POSITIVITY IN OLD AGE

  I suggest that an old-age positivity effect operates in a similar fashion to choosing to listen to pleasing music. By age sixty (if not earlier), a striking bias sets in toward positive social perceptions and memories. The original experiment had people looking at two faces next to each other on a screen, one with a neutral expression and one with either a positive or a negative one. After one second, the faces are removed from the screen and a dot appears where one of the faces was located. The person must hit a button as soon as the dot is perceived, one button for left side, one for right side. At ages twenty to thirty, people are equally quick to spot the dot no matter what face it was associated with. But by age sixty, a bias appears: the dot is perceived more quickly if it succeeds the positive face and more slowly if it succeeds the negative one. Study of eye movements shows that the older people spend more time inspecting faces with positive expressions than negative, and the positive ones are remembered later more often. Young people show none of these biases. These results are true among Asians, Europeans, and Americans. They appear to involve a measurable effect in the amygdala, where positive faces evoke a stronger response than negative ones in older people but not in younger people. Finally, older people tend to respond to a negative mood induced by unpleasant music by preferentially looking at positive faces, as if attempting actively to counter the negative and maintain or induce a positive mood. Young people tend, if anything, to be mood congruent—if made to feel bad, they look more at negative faces.

  Why show such a positivity bias? Young people would be wise to pay attention to reality—both positive and negative—the better to make the appropriate responses later. Avoiding negative information seems risky on its face—negative events may have as big an effect on one’s interests (inclusive fitness) as positive ones. By contrast, in old age it hardly matters what you learn, but greater positive affect is associated with stronger immune response, so you may be selected to trade a grasp of reality for a boost in dealing with your main problem, that of internal enemies, including cancer. A positivity bias sacrifices attention to and learning from negative stimuli the better to enjoy strong immune function now. If you haven’t learned to spot an external enemy by now, chances may be low that you will learn to, and in the meantime you can enjoy a positive mood and immune response. Grandchildren may admire Gramps and Grandma because nothing seems to faze them, but Gramps and Grandma are living in positivity land—they may scarcely know the difference.

  It is an interesting coincidence that although people’s implicit bias in favor of youth over old age hardly changes with age (as measured by an IAT)—from twenty to seventy, they favor young over old—by our forties, our explicit bias in favor of youth (what we say we care about) declines until at exactly sixty, people start to say they think older is better than younger. Like everyone else, they implicitly associate youth with positive features, but they start preaching the opposite at roughly the same time they display the old-age positivity bias.

  Note that the positivity effect requires no suppression of negative information or affect. The bias occurs right away. People simply do not attend to the negative information, do not look at it, and do not remember it. Thus, the possible negative immune effects of affect suppression do not need to arise. This must be a general rule—the earlier during information processing that self-deception occurs, the less its negative downstream immunological effects. At the same time, there may be greater risk of disconnect from reality, since the truth may be minimally stored or not at all.

  Given what I have just said, the question arises of why old people are often perceived as being cranky or grumpy. This appears to result from an entirely independent mechanism, which sometimes cancels out or overwhelms the positivity bias. With increasing age, for reasons that are not entirely clear, people suffer greater deficits in their inhibitory abilities, that is, their ability to stop behavior under way that they may wish to stop. Since people often wish to inhibit behavior that will be seen as socially inappropriate, it is not surprising that with increasing age comes exactly that, increasingly socially inappropriate behavior. This includes discussion of private material in public, more frequent overt expressions of prejudice and stereotype, greater difficulty taking the perspective of another, and more off-target verbosity (“Don’t get me started!”). Perhaps many of these traits are later described or rationalized by saying that Gramps sure is “cranky” today.

  AN IMMUNOLOGICAL THEORY OF HAPPINESS

  All of this work is consistent with an immunological theory of human happiness in which a finely tuned immune system purring along at near-peak efficiency with hardly a target in sight would be experienced internally as a highly enjoyable state. Even such variables as absence of food (hunger) or water (thirst) must be at least partly aversive because of their negative effects on the immune system. At the very least, it must be true that as the brain looks outward and acts to increase inclusive fitness in part by increasing happiness, then surely the same must be true when looking inwardly.

  According to this view, the brain is split between outward-directed and inward-directed activity. In the outside world, many features are stationary and predictable—the shape of your bedroom, the location of food in your refrigerator, the way to work, etc. Within this world, of course, there is important variation: a predator appears, a food source, a possible mating opportunity, a hole in the street, for all of which you are selected to make appropriate responses. You have an internal reward/punishment system that goads you in appropriate directions.

  Now imagine the whole thing all over for the internal system. Your brain looks inward and sees many constant features—feet and hands farther from it than the trunk, a particular circulatory system through which almost all chemicals must ultimately pass, including those produced by the brain to regulate downstream chemical activity. But in this world also live (in principle) hundreds and even thousands of species of parasites, at the moment just a few, perhaps, but taking particular configurations that need to be countered. The brain may receive or note signals that a major infection is under way in the lower left abdomen but miss the fact that a core of parasitic cells resides in the right big toe and are capable of generating the primary attack.

  One important distinction concer
ns consciousness. We are highly conscious of interactions outside our bodies but highly unconscious of interactions within the body. Why? Part of it is that many signals to self need no consciousness, but one wonders why we are so unconscious of parasitic interactions—for example, failing to appreciate the meaning of “sickness behavior” or the value of more sleep.

  Despite its importance, almost no attention has been directed toward measuring the correlates of immune function with such major components of individual fitness—or reproductive success—as survival, fecundity, physical attractiveness, and so on. The comparative work has all been done in birds. Here the pattern is clear. A greater natural immune response to some kind of challenge is positively associated with survival in nature and in the lab, and the effect size is relatively large—18 percent of variation in survival is explained by immune variation, while the closest competitor, degree of bodily symmetry, explains only 6 percent of variance in survival.

  How is optimism related to immune function? A number of studies have shown a positive correlation between optimism and health outcomes, immune function, and survival. A recent study is especially striking. Law students were assayed five times throughout the year both for optimism regarding their studies and for a major immune parameter. Within a student’s year, high optimism was associated with high immune function, but when comparing students, there was no effect; that is, optimistic students were not more likely to have stronger immune systems. Although psychologists almost uniformly assume that mood affects immune system, the reverse is equally plausible. With your immune system at near-top efficiency, you should feel happy, positive, and optimistic.