When is a belief system not only false but so encouraging of falsity and needless suffering as to be worthy of our condemnation? According to a recent poll, 36 percent of British Muslims (ages sixteen to twenty-four) think apostates should be put to death for their unbelief. 60 Are these people "morally motivated," in Haidt's sense, or just morally confused?
And what if certain cultures are found to harbor moral codes that look terrible no matter how we jigger Haidt's five variables of harm, fairness, group loyalty, respect for authority, and spiritual purity? What if we find a group of people who aren't especially sensitive to harm and fairness, or cognizant of the sacred, or morally astute in any other way? Would Haidt's conception of morality then allow us to stop these benighted people from abusing their children? Or would that be unscientific?
The Moral Brain
Imagine that you are having dinner in a restaurant and spot your best friend's wife seated some distance away. As you stand to say hello, you notice that the man seated across from her is not your best friend, but a handsome stranger. You hesitate. Is he a colleague of hers from work? Her brother from out of town? Something about the scene strikes you as illicit. While you cannot hear what they are saying, there is an unmistakable sexual chemistry between them. You now recall that your best friend is away at a conference. Is his wife having an affair? What should you do?
Several regions of the brain will contribute to this impression of moral salience and to the subsequent stirrings of moral emotion. There are many separate strands of cognition and feeling that intersect here: sensitivity to context, reasoning about other people's beliefs, the interpretation of facial expressions and body language, suspicion, indignation, impulse control, etc. At what point do these disparate processes constitute an instance of moral cognition? It is difficult to say. At a minimum, we know that we have entered moral territory once thoughts about morally relevant events (e.g., the possibility of a friend's betrayal) have been consciously entertained. For the purposes of this discussion, we need draw the line no more precisely than this.
The brain regions involved in moral cognition span many areas of the prefrontal cortex and the temporal lobes. The neuroscientists Jorge Moll, Ricardo de Oliveira-Souza, and colleagues have written the most comprehensive reviews of this research. 61 They divide human actions into four categories:
1. Self-serving actions that do not affect others
2. Self-serving actions that negatively affect others
3. Actions that are beneficial to others, with a high probability of reciprocation ("reciprocal altruism")
4. Actions that are beneficial to others, with no direct personal benefits (material or reputation gains) and no expected reciprocation ("genuine altruism"). This includes altruistic helping as well as costly punishment of norm violators ("altruistic punishment") 62
As Moll and colleagues point out, we share behaviors 1 through 3 with other social mammals, while 4 seems to be the special province of human beings. (We should probably add that this altruism must be intentional/conscious, so as to exclude the truly heroic self-sacrifice seen among eusocial insects like bees, ants, and termites.) While Moll et al. admit to ignoring the reward component of genuine altruism (often called the "warm glow" associated with cooperation), we know from neuroimaging studies that cooperation is associated with heightened activity in the brain's reward regions. 63 Here, once again, the traditional opposition between selfish and selfless motivation seems to break down. If helping others can be rewarding, rather than merely painful, it should be thought of as serving the self in another mode.
It is easy to see the role that negative and positive motivations play in the moral domain: we feel contempt/anger for the moral transgressions of others, guilt/shame over our own moral failings, and the warm glow of reward when we find ourselves playing nicely with other people. Without the engagement of such motivational mechanisms, moral prescriptions (purely rational notions of "ought") would be very unlikely to translate into actual behaviors. The fact that motivation is a separate variable explains the conundrum briefly touched on above: we often know what would make us happy, or what would make the world a better place, and yet we find that we are not motivated to seek these ends; conversely, we are often motivated to behave in ways that we know we will later regret. Clearly, moral motivation can be uncoupled from the fruits of moral reasoning. A science of morality would, of necessity, require a deeper understanding of human motivation.
The regions of the brain that govern judgments of right and wrong include a broad network of cortical and subcortical structures. The contribution of these areas to moral thought and behavior differs with respect to emotional tone: lateral regions of the frontal lobes seem to govern the indignation associated with punishing transgressors, while medial frontal regions produce the feelings of reward associated with trust and reciprocation. 64 As we will see, there is also a distinction between personal and impersonal moral decisions. The resulting picture is complicated: factors like moral sensitivity, moral motivation, moral judgment, and moral reasoning rely on separable, mutually overlapping processes.
The medial prefrontal cortex (MPFC) is central to most discussions of morality and the brain. As discussed further in chapters 3 and 4, this region is involved in emotion, reward, and judgments of self-relevance. It also seems to register the difference between belief and disbelief. Injuries here have been associated with a variety of deficits including poor impulse control, emotional blunting, and the attenuation of social emotions like empathy, shame, embarrassment, and guilt. When frontal damage is limited to the MPFC, reasoning ability as well as the conceptual knowledge of moral norms are generally spared, but the ability to behave appropriately toward others tends to be disrupted.
Interestingly, patients suffering from MPFC damage are more inclined to consequentialist reasoning than normal subjects are when evaluating certain moral dilemmas—when, for instance, the means of sacrificing one person's life to save many others is personal rather than impersonal. 65 Consider the following two scenarios:
1. You are at the wheel of a runaway trolley quickly approaching a fork in the tracks. On the tracks extending to the left is a group of five railway workmen. On the tracks extending to the right is a single railway workman.
If you do nothing the trolley will proceed to the left, causing the deaths of the five workmen. The only way to avoid the deaths of these workmen is to hit a switch on your dashboard that will cause the trolley to proceed to the right, causing the death of the single workman.
Is it appropriate for you to hit the switch in order to avoid the deaths of the five workmen?
2. A runaway trolley is heading down the tracks toward five workmen who will be killed if the trolley proceeds on its present course. You are on a footbridge over the tracks, in between the approaching trolley and the five workmen. Next to you on this footbridge is a stranger who happens to be very large.
The only way to save the lives of the five workmen is to push this stranger off the bridge and onto the tracks below where his large body will stop the trolley. The stranger will die if you do this, but the five workmen will be saved.
Is it appropriate for you to push the stranger onto the tracks in order to save the five workmen? 66
Most people strongly support sacrificing one person to save five in the first scenario, while considering such a sacrifice morally abhorrent in the second. This paradox has been well known in philosophical circles for years. 67 Joshua Greene and colleagues were the first to look at the brain's response to these dilemmas using fMRI. 68 They found that the personal forms of these dilemmas, like the one described in scenario two, more strongly activate brain regions associated with emotion. Another group has since found that the disparity between people's responses to the two scenarios can be modulated, however slightly, by emotional context. Subjects who spent a few minutes watching a pleasant video prior to confronting the footbridge dilemma were more apt to push the man to his death. 69
The fact that
patients suffering from MPFC injuries find it easier to sacrifice the one for the many is open to differing interpretations. Greene views this as evidence that emotional and cognitive processes often work in opposition. 70 There are reasons to worry, however, that mere opposition between consequentialist thinking and negative emotion does not adequately account for the data. 71
I suspect that a more detailed understanding of the brain processes involved in making moral judgments of this type could affect our sense of right and wrong. And yet superficial differences between moral dilemmas may continue to play a role in our reasoning. If losses will always cause more suffering than forsaken gains, or if pushing a person to his death is guaranteed to traumatize us in a way that throwing a switch will not, these distinctions become variables that constrain how we can move across the moral landscape toward higher states of well-being. It seems to me, however, that a science of morality can absorb these details: scenarios that appear, on paper, to lead to the same outcome (e.g., one life lost, five lives saved), may actually have different consequences in the real world.
Psychopaths
In order to understand the relationship between the mind and the brain, it is often useful to study subjects who, whether through illness or injury, lack specific mental capacities. As luck would have it, Mother Nature has provided us with a nearly perfect dissection of conventional morality. The resulting persons are generally referred to as "psychopaths" or "sociopaths," 72 and there seem to be many more of them living among us than most of us realize. Studying their brains has yielded considerable insight into the neural basis of conventional morality.
As a personality disorder, psychopathy has been so sensationalized in the media that it is difficult to research it without feeling that one is pandering, either to oneself or to one's audience. However, there is no question that psychopaths exist, and many of them speak openly about the pleasure they take in terrorizing and torturing innocent people. The extreme examples, which include serial killers and sexual sadists, seem to defy any sympathetic understanding on our parts. Indeed, if you immerse yourself in this literature, each case begins to seem more horrible and incomprehensible than the last. While I am reluctant to traffic in the details of these crimes, I fear that speaking in abstractions may obscure the underlying reality. Despite a steady diet of news, which provides a daily reminder of human evil, it can be difficult to remember that certain people truly lack the capacity to care about their fellow human beings. Consider the statement of a man who was convicted of repeatedly raping and torturing his nine-year-old stepson:
After about two years of molesting my son, and all the pornography that I had been buying, renting, swapping, I had got my hands on some "bondage discipline" pornography with children involved. Some of the reading that I had done and the pictures that I had seen showed total submission. Forcing the children to do what I wanted.
And I eventually started using some of this bondage discipline with my own son, and it had escalated to the point where I was putting a large Zip-loc bag over his head and taping it around his neck with black duct tape or black electrical tape and raping and molesting him ... to the point where he would turn blue, pass out. At that point I would rip the bag off his head, not for fear of hurting him, but because of the excitement.
I was extremely aroused by inflicting pain. And when I see him pass out and change colors, that was very arousing and heightening to me, and I would rip the bag off his head and then I'd jump on his chest and masturbate in his face and make him suck my penis while he ... started to come back awake. While he was coughing and choking, I would rape him in the mouth.
I used this same sadistic style of plastic bag and the tape two or three times a week, and it went on for I'd say a little over a year. 73
I suspect that this brief glimpse of one man's private passions will suffice to make the point. Be assured that this is not the worst abuse a man or woman has ever inflicted upon a child just for the fun of it. And one remarkable feature of the literature on psychopaths is the extent to which even the worst people are able to find collaborators. For instance, the role played by violent pornography in these cases is difficult to overlook. Child pornography alone—which, as many have noted, is the visual record of an actual crime—is now a global, multibillion-dollar industry, involving kidnapping, "sex tourism," organized crime, and great technical sophistication in the use of the internet. Apparently, there are enough people who are eager to see children—and, increasingly, toddlers and infants—raped and tortured so as to create an entire subculture. 74
While psychopaths are especially well represented in our prisons, 75 many live below the threshold of overt criminality. For every psychopath who murders a child, there are tens of thousands who are guilty of far more conventional mischief. Robert Hare, the creator of the standard diagnostic instrument to assess psychopathy, the Psychopathy Checklist-Revised (PCL-R), estimates that while there are probably no more than a hundred serial killers in the United States at any moment, there are probably 3 million psychopaths (about 1 percent of the population). 76 If Hare is correct, each of us crosses paths with such people all the time.
For instance, I recently met a man who took considerable pride in having arranged his life so as to cheat on his wife with impunity. In fact, he was also cheating on the many women with whom he was cheating—for each believed him to be faithful. All this gallantry involved aliases, fake businesses, and, needless to say, a blizzard of lies. While I can't say for certain this man was a psychopath, it was quite apparent that he lacked what most of us would consider a normal conscience. A life of continuous deception and selfish machination seemed to cause him no discomfort whatsoever. 77
Psychopaths are distinguished by their extraordinary egocentricity and their total lack of concern for the suffering of others. A list of their most frequent characteristics reads like a personal ad from hell: they are said to be callous, manipulative, deceptive, impulsive, secretive, grandiose, thrill-seeking, sexually promiscuous, unfaithful, irresponsible, prone to both reactive and calculated aggression, 78 and lacking in emotional depth. They also show reduced emotional sensitivity to punishment (whether actual or anticipated). Most important, psychopaths do not experience a normal range of anxiety and fear, and this may account for their lack of conscience.
The first neuroimaging experiment done on psychopaths found that, when compared to nonpsychopathic criminals and noncriminal controls, they exhibit significantly less activity in regions of the brain that generally respond to emotional stimuli. 79 While anxiety and fear are emotions that most of us would prefer to live without, they serve as anchors to social and moral norms. 80 Without an ability to feel anxious about one's own transgressions, real or imagined, norms become nothing more than "rules that others make up." 81 The developmental literature also supports this interpretation: fearful children have been shown to display greater moral understanding. 82 It remains an open question, therefore, just how free of anxiety we can reasonably want to be. Again, this is something that only an empirical science of morality could decide. And as more effective remedies for anxiety appear on the horizon, this is an issue that we will have to confront in some form.
Further neuroimaging work suggests that psychopathy is also a product of pathological arousal and reward. 83 People scoring high on the psychopathic personality inventory show abnormally high activity in the reward regions of their brain (in particular, the nucleus accumbens) in response to amphetamine and while anticipating monetary gains. Hypersensitivity of this circuitry is especially linked to the impulsive-antisocial dimension of psychopathy, which leads to risky and predatory behavior. Researchers speculate that an excessive response to anticipated reward can prevent a person from learning from the negative emotions of others.
Unlike others who suffer from mental illness or mood disorders, psychopaths generally do not feel that anything is wrong with them. They also meet the legal definition of sanity, in that they possess an intellectual understanding of the diff
erence between right and wrong. However, psychopaths generally fail to distinguish between conventional and moral transgressions. When asked "Would it be okay to eat at your desk if the teacher gave you permission?" vs. "Would it be okay to hit another student in the face if the teacher gave you permission?" normal children age thirty-nine months and above tend to see these questions as fundamentally distinct and consider the latter transgression intrinsically wrong. In this, they appear to be guided by an awareness of potential human suffering. Children at risk for psychopathy tend to view these questions as morally indistinguishable.
When asked to identify the mental states of other people on the basis of photographs of their eyes alone, psychopaths show no general impairment. 84 Their "theory of mind" processing (as the ability to understand the mental states of others is generally known) seems to be basically intact, with subtle deficits resulting from their simply not caring about how other people feel. 85 The one crucial exception, however, is that psychopaths are often unable to recognize expressions of fear and sadness in others. 86 And this may be the difference that makes all the difference.
Neuroscientist James Blair and colleagues suggest that psychopathy results from a failure of emotional learning due to genetic impairments of the amygdala and orbitofrontal cortex, regions vital to the processing of emotion. 87 The negative emotions of others, rather than parental punishment, may be what goad us to normal socialization. Psychopathy, therefore, could result from a failure to learn from the fear and sadness of other people. 88
A child at risk for psychopathy, being emotionally blind to the suffering he causes, may increasingly resort to antisocial behavior in pursuit of his goals throughout adolescence and adulthood. 89 As Blair points out, parenting strategies that increase empathy tend to successfully mitigate antisocial behavior in healthy children; such strategies inevitably fail with children who present with the callousness/unemotional (CU) trait that is characteristic of psychopathy. While it may be difficult to accept, the research strongly suggests that some people cannot learn to care about others. 90 Perhaps we will one day develop interventions to change this. For the purposes of this discussion, however, it seems sufficient to point out that we are beginning to understand the kinds of brain pathologies that lead to the most extreme forms of human evil. And just as some people have obvious moral deficits, others must possess moral talent, moral expertise, and even moral genius. As with any human ability, these gradations must be expressed at the level of the brain.