Disgust, Morality, and Human Identity
Metanexus: Views 2001.12.03 5792 words
What is embedded or embodied morality? As we try to become more in tunewith, more at home in, this world in which we find ourselves, do we becomeincreasingly guilty of committing the naturalistic fallacy, of convertingour comfortable “is” into an obligatory “ought”? Or do we come closer andcloser to a sure knowledge of ourselves, and thus of what is right and wrongfor ourselves? How natural are our natural reactions? Moreover, howenculturated are they? As Pascal observes in his Pensees: “I am much afraidthat nature is itself only a first custom [culture], as custom [culture] isa second nature.” So, how do we determine morality on the basis of a naturethat is nothing but a kind of sub- or unconscious culture?
In today’s column, Heather Looy, associate professor of psychology at TheKing’s University College in Alberta, Canada, explores the role that disgustplays both naturally and culturally in our understanding of morality. As she observes in the abstract to her paper:
“Theologically, the Judeo-Christian tradition uses disgust and relatedconcepts of abomination and impurity in conjunction with moral codesdesigned to preserve communal identity as the people of God. Psychosocialresearch reveals disgust as a universal emotion that enables evaluation andregulation of one class of moral behaviors, and serves to express andpreserve cultural identity. Neurobiology is beginning to trace the neuralcircuitry involved in disgust and morality, suggesting emotions are thebasis for moral judgement, and revealing intriguing relationships betweendisgust, morality, and other aspects of the psyche.”
But if emotion, and not reason, is the basis for human morality, is thenaturalistic fallacy that fallacious after all? What roles do emotion andreason play in the instantiating of morality as disgust? Read on to exploresome of the possible answers to these questions. Also, a list of referencesas well as notes and the paper’s abstract are to be found at the end of thecolumn.
As previously mentioned, Heather Looy is an associate professor ofpsychology at The King’s University College, a Christian liberal artscollege in Edmonton, Alberta, Canada. She received her Ph.D. in 1991 fromMcMaster University in Hamilton, Ontario. She teaches courses in brain andbehavior, evolution, genes and behavior, perception, cognition, learning andmemory, and research methods. She is a biopsychologist by training and hertheoretical and empirical research interests reflect her passion forquestions about human embodiment and embeddedness in creation, for findinginterconnections across subdisciplines and disciplines; and for integratingquestions of faith and psychological science. They include thebiopsychology and evolutionary psychology of sexuality and gender (sexualorientation, intersexuality); food preferences, disgust, and culture;biology and human nature; and ecopsychology.
–Stacey E. Ake
Subject: Disgust, Morality, and Human Identity: A Neurobiological,Psychosocial and Theological InvestigationFrom: Heather LooyEmail: <[email protected]>
Humans are universally moral beings. We have the capacity, tendency, andmotivation to evaluate objects, events, and behaviors as good or bad. Thespecific applications of this moral sensibility, however, vary acrosshistorical, cultural, and religious locations. In our efforts to resolvethe dilemmas that occur as diverse moral frameworks increasingly conflict inour shrinking world, scholars seek a deeper understanding of the sources,functions, and nature of human morality. That this task has borne limitedfruit attests both to the fact that morality is a broad-ranging, enormouslycomplex phenomenon, and that questions of human morality touch on our mostbasic beliefs about the world.
Scholars not surprisingly contribute different worldviews and disciplinaryallegiances to their understanding of morality. For example, someunderstand morality as evolved neurobiological processes manifested inpsychobehavioral adaptations that ultimately serve the interests of ourgenes. Others view morality as sociocultural constructions that contributeto social stability but are infinitely flexible, unconstrained byevolutionary biology, neural organization, or transcendent truth. Stillothers argue that morality is a property of a disembodied human rationality,perhaps in correct relationship with a nonmaterial divinity who determinesand communicates moral laws.
This admittedly oversimplified list reveals the diversity of perspectives onhuman morality. Each involves an unnecessary degree of reductionism andsimplification. It is the complexity of morality that we most urgentlyneed to acknowledge and examine as we struggle to understand andappropriately respond to events such as the terrorist attacks on the U.S. inSeptember, 2001. There is tremendous potential to enrich and transform ourunderstanding of human morality through interdisciplinary investigations,based on a view of human nature as a multidimensional unity (see Anderson,1998; Brown, 1998; Jeeves, 1997, pp. 98-126), that includes real,irreducible, and mutually interdependent spiritual, relational, emotional,rational, and physiological facets.
To illustrate this vision with a relatively simple example, I begin with theemotion of disgust.  Disgust is deeply rooted in our bodies, bothviscerally and neurally, and therefore reflects our embodiment andevolutionary history. Disgust is a “moral emotion”, involving evaluation ofrightness or wrongness. Human relationality is expressed by the fact thatthe triggers of disgust are learned in community, and play a crucial role incultural identity. Finally, many disgust triggers are linked explicitly todivine expectations, reflecting human spirituality. We cannot understandthe nature and meaning of disgust and its role in human morality withouttaking seriously all of these dimensions.
A systematic study of disgust from multiple perspectives would enrich ourunderstanding of human morality as simultaneously embodied, cultural, andspiritual. It further provides a model for scholars to explore the roles ofother emotional, perceptual, cognitive and neural processes involved inhuman morality. This essay is an initial attempt to identify the majorissues, questions, and contributions that theology, the social sciences, andneurobiology have to offer this enterprise, and an invitation to scholarswith expertise in these fields to respond.
Embodied morality: Natural moral law
For the purposes of this paper, I define morality, or “moral sensibility”,as the universal human capacity and motivation to evaluate objects, eventsand behaviors as good or bad, right or wrong. In theology, the concept of”natural moral law” refers to the belief that this universal human capacityis innately embedded in human nature. Aristotle argued that everything hasa telos, or final purpose, and any action that moves something toward itsfinal purpose is “good”. Medieval theologians, particularly Thomas Aquinas,drew on this idea to argue that God placed laws into creation that, ifobeyed, would lead humans to their highest good or final purpose. TheHebrew and Christian scriptures speak of God’s law being written on people’shearts (e.g., Jeremiah 31:33, Romans 2:14-15, Hebrews 8:10; 10:15). Theconcepts of “common grace” and “general revelation” also capture the ideathat God has placed within humankind the capacity to discern right fromwrong and a general agreement about what is right and wrong. Natural morallaw differs from other laws of nature in that, while humans have thecapacity to discern and obey them, we are not compelled, but have thefreedom to disobey them (Lewis, 1942).
This concept of natural moral law is controversial, at least in theChristian tradition. The notion that God writes this knowledge on people’shearts can be interpreted as an innate moral wisdom available to everyone byvirtue of their humanity (e.g., Lewis, 1942), but can also be understood assomething that occurs only when a person joins the community of believers(McKenna, 1997). Further, if people naturally know what is good, and havethe capacity and motivation to act in ways that promote the good, then wemight expect more widespread agreement on moral laws and less difficulty inobeying them. We must also avoid the naturalistic fallacy, the belief thatwhat is natural is how things ought to be: natural = good.
Nevertheless, the idea of an innate natural moral law is consistent with amultidimensional view of human nature, with the belief that morality isreflected not solely spiritually, but as an embodied and psychologicallyexperienced phenomenon. This allows us to explore the implications ofevolutionary theory, neurobiology, and psychology for human morality,without marginalizing its real spiritual aspect, and without necessarilyaccepting the philosophical naturalism that frequently imbues these fields.Even within faith traditions, we find morality expressed in socioculturaland emotional terms. For example, the Hebrew scriptures claim that God’smoral law is given to a particular community for particular purposes,including a strong sense of communal identity and purpose. Further,obedience to those laws is explicitly linked to emotional states, inparticular, disgust (Kekes, 1992; Stout, 1988, pp. 145-162). In Leviticus,violations of Hebrew laws are frequently described as abominations, whichare by definition objects of disgust (e.g. Leviticus 11:13, 18). The Hebrewprophets called acts of disobedience abominations in God’s sight (e.g.,Isaiah, Jeremiah, Ezekiel, Amos). The psalms speak of the faithless asdisgusting (Psalm 119:158), and the Christian scriptures speak of Godspitting out the weakly committed, a classic disgust reaction (Revelation3:16).
Embedded morality: Morality and cultural identity
But what is disgust? What role does it play in enabling us to evaluate andregulate behavior in terms of moral categories, and what does it tell usabout the function of morality in human life? To answer this question, wefirst need a sketch of morality from a psychosocial perspective.
Morality appears to be uniquely human (although see Flack & deWaal, 2000;but also Kagan, 2000). Culture is also uniquely human, and highly varied.This variation includes the application of moral sensibility; that is, howobjects, events, and behaviors are evaluated. These cross-culturaldifferences support the suggestion that one function of morality is toestablish and maintain cultural identity. That is, “we” do this, eat that,and shun those, unlike “them”. This helps us know who we are, our place andpurpose in the order of things (Douglas, 1966).
Of course, morality addresses much more than those behaviors concerned withcultural identity and purity. Shweder, Much, Mahapatra and Park (1997)propose that we classify moral codes as reflecting autonomy, community, ordivinity. When we morally evaluate, the criteria we use draw primarily uponone of these three categories. Autonomy emphasizes individual rights andpreferences, while Community focuses on one’s social role and the importanceof sustaining social systems and institutions. These are relevant andimportant dimensions of human morality, but for present purposes I willfocus on the category of Divinity. When we engage in moral evaluation usingthe criteria of Divinity we address personal purity (physical andspiritual), cultural identity, divine expectations, and natural law, sin,and defilement. This bears obvious connections to the theological conceptof natural moral law.
The divinity code has been explored by several social scientists, among themanthropologists (Douglas, 1966; Shweder et al., 1997) and psychologists(e.g., Rozin, Lowery, Imada & Haidt, 1999). It also appears inphilosophical and theological discourse on ethics (e.g., Kekes, 1992; Stout,1988). These scholars have convincingly established the existence of adivinity-based moral code, present to some degree in (presumably) all humancultures.
Embedded morality: Disgust in psychosocial perspective
Social scientists have also examined the psychological foundations of humanmorality. While some scholars have focused on the rational cognitiveprocesses involved in moral reasoning (Gilligan, 1982; Kohlberg, 1971), morerecently others have argued that human morality is based primarily onemotions (Haidt, Koller & Dias, 1993; Rozin et al., 1999). Cross-culturalstudies suggest that moral evaluations are best predicted by emotionalresponses, a “gut reaction” which is then justified rationally (Haidt etal., 1993). Emotions can also act as powerful regulators of our ownbehavior. Imagine behaving in an activity you find disgusting, such aseating pork if you are Jewish or a “moral vegetarian”, a homoerotic act oreven drinking alcohol if you are a particular subtype of Christian. Yourdisgust significantly reduces the likelihood that you will engage in suchacts.
The emotions associated with moral violations include guilt, shame, fear,anger, and contempt, but disgust has generated the most recent interest(Haidt, Rozin, McCauley & Imada, 1997; Rozin, Markwith & Stoess, 1997).Disgust has been explicitly linked to the divinity code: moral violationsthat involve desecration, certain sins, or acts that disrupt the perceivednatural order of things tend to elicit disgust (Rozin et al., 1999; Rozin etal., 1997). These include, for North Americans, eating human flesh, seeingan eviscerated dead body, engaging in an incestuous relationship, spittingupon another person, or eating insects (Rozin & Fallon, 1987; Wood & Looy,2000).1 Globally, disgust triggers fall into one of three categories: bodyenvelope violations, sex taboos, and food taboos (Rozin & Fallon, 1987).
Disgust is one of six basic human emotions (Ekman, 1992). It is universallyexperienced as a visceral rejection, even nausea, and is universallyrecognized through its distinctive facial expression (Rozin, Lowery & Ebert,1994; Steiner, 1979). It has roots in an innate rejection of bitter tastes,evident in other mammals and in human neonates (Steiner, 1979). This innateresponse has obvious survival benefits, since bitter-tasting substances areless likely to be nutritious and more likely to bear toxins thansweet-tasting substances. However in humans this “emotion of rejection”becomes highly elaborated, extending far beyond physical survival. Haidt etal. (1997) argue persuasively that the triggers of disgust are things thatremind us forcibly of the animalness of our nature, and therefore of our”impurity” and degradation (Haidt et al., 1997). Disgust, therefore, “isbest understood as the guardian of the temple of the body” (Haidt et al.,1997, p.114; see also Miller, 1997).
Triggers of disgust are both learned and context-dependent. Young childrenexpress disgust solely to bitter tastes, yet by 8 to 12 years of age, theyhave adopted the full array of adult disgust triggers in their particularculture. They also learn that disgust triggers are defined by theircontext. For example, while normally contact with feces makes one impure,the act of caring for a young infant both renders the feces somewhat lessdisgusting and, more importantly, releases the caregiver from moralcondemnation for the contact. Further, disgusting acts performed undercoercion confer less impurity than if one is perceived as having a choice.
Why do we so consistently and unfailingly socialize our children to rejectcertain objects, events, and behaviors, in particular contexts? Perhaps thepurpose is to create and preserve cultural identity. This is seen veryclearly with food. There is a vast array of edible, nourishing substancesavailable to every cultural group, yet without exception, a given culturewill accept only a limited subset. People who eat substances rejected by aparticular culture are either confirmed as outsiders, or at least viewed asdeviant. For example, the English once scorned the French for eating frogsand snails, and North Americans think anyone who voluntarily eats insectsmust be “primitive, barbaric, or desperate” (Forsyth, 1994, p.63). Noticethat these are moral evaluations: particular foods are morally good or bad,and confer this quality to the people who eat them. Disgust acts as asignal that eating this particular food is morally wrong.
Thus disgust enables one to maintain cultural identity and purity byeffectively avoiding or rejecting anything that might threaten it. Disgustkeeps one accepted within the community, and recognizable as one of “ourown”. This sense of belonging is vital for human development andpsychological well being. The fact that feral children, developing apartfrom human community, reportedly fail to show any disgust response is a casein point (Malson, 1964; cited in Haidt et al., 1997).
Embodied morality: Disgust in the brain?
If indeed “core disgust” (Rozin & Fallon, 1987) is innate, and if humanshave throughout human evolutionary history elaborated this response incommunal contexts, then we should expect disgust to be manifested inneurobiological systems, through natural selection. Is this the case? Andare the neurobiological aspects of disgust and of morality related in waysthat might illuminate their relationship?
Until recently, it was believed that human emotions involved a common neuralsystem (mainly the limbic system; LeDoux, 1996); however there is nowevidence that basic emotions involve separate neural systems (Phillips,Young, Scott, et al., 1998; Sprengelmeyer, Rausch, Eysel & Przuntek, 1998).This implies that the basic emotions evolved for different reasons andpossibly at different times in evolutionary history. However, evolutionarypsychology has not yet provided a specific and empirically supported accountfor the emergence of disgust (Cosmides & Tooby, 2000; Nesse, 1990; but seeDarwin, 1965).
The neurobiological study of disgust has shown that facial expressions ofdisgust appear to involve activation of the basal ganglia, particularly theright anterior putamen and caudate nucleus, as well as the left anteriorinsular cortex (Sprengelmeyer et al., 1998; Phillips, Young, Scott et al.,1998; Phillips, Young, Senior, et al., 1997). These areas may also processresponses to auditory disgust stimuli such as sounds of retching (Calder,Keane, Manes et al., 2000). The experience of disgust may involve similarregions (Calder et al., 2000; Sprengelmeyer, Young, Calder, et al., 1996),as well as the lateral cerebellum and the occipitotemporal cortex (Lane,Reiman, Ahern et al., 1997). These appear to be disgust-specific, insteadof more generally processing perceptual abilities or basic emotions.
The specific regions involved in disgust are suggestive. The fact that theinterior forebrain structures involved in disgust affect autonomic andneuroendocrine processes is consistent with the experience of disgust asliterally a “gut” response. In primates, the anterior insula is thegustatory cortex, involved in the perception and hedonic evaluation oftastes and smells, in feeding and vomiting (Phillips et al., 1997). It alsomay be involved in language perception (Phillips et al., 1998). This isgenerally consistent with the observation that disgust in its unelaboratedform involves a visceral response to smells and tastes that have beenevaluated as unpleasant, and that visual and certain acoustic stimuli canbecome secondary conditioned stimuli for those tastes and smells. Thecaudate nucleus may be involved in stimulus-response learning (Sprengelmeyeret al., 1996). Disgust, as noted earlier, is elaborated through experienceto be elicited by more complex events than unpleasant tastes and smells, andbehavioral psychologists have long established that emotional responses aresubject to simple and powerful stimulus-response conditioning processes.
Higher level integrative processing of all emotions involves severalcortical regions. Adolphs, Damasio, Tranel and Damasio (1996) showed thatrecognition of facial expressions of emotion involves the right inferiorparietal cortex and the right infracalarine cortex. However, Sprengelmeyeret al. (1998) showed that the left inferior frontal cortex is involved inrecognition of the facial expressions of emotions of disgust, fear andanger. They suggest that “recognition of emotion is based on separateneural pathways; it is hypothesized that these pathways project to theinferior frontal cortex (Sprengelmeyer et al., 1998, p.1931). Lane et al.(1997) report that the experience and recall of emotions involve activationof the thalamus and medial prefrontal cortex, while Canli, Desmond, Zhao etal. (1998) further suggest this function is lateralized to the righthemisphere.
A close examination of these neurobiological studies of emotional perceptionand experience, however, shows critical differences across studies inmethodology and sampling, and, while a few consistent observations arereported, there are many inconsistencies. At present there is insufficientdata to confirm preliminary findings, and our limited understanding ofneurobiology renders interpretation difficult. Nevertheless, the fact thatthe perception and experience of disgust are manifested in dedicated neuralcircuits has been well established.
None of this research, however, addresses the question of whether disgust isneurally linked with morality. To do that, we must first establish theneural systems involved in morality, then trace connections between thesesystems and those involved with disgust. Only recently has this questionbeen directly addressed, interestingly, by an interdisciplinary team led bya philosopher. Researchers used fMRI to demonstrate that, when respondingto moral dilemmas, people show activation of brain regions involved inemotional experience, including the medial frontal cortex, the posteriorcingulate and anterior gyri, and not in frontal cortical areas known to beinvolved in judgement (Greene, Sommerville, Nystrom, et al., 2001). Thissupports the psychological argument that moral evaluation is based primarilyon emotion, not reason, and lends credence to the need to examine moreclosely the role of emotions in morality.
Morality and disgust in multidimensional, interdisciplinary perspective
Intriguing links emerge among these theological, psychosocial, andneurobiological perspectives on disgust and morality, some of which I havealready alluded to. The psychological argument that disgust is the guardianof the temple of the body (Haidt et al., 1997) finds echoes in the Leviticallaws that focus on uncleanness and impurity, and specify which foods, sexacts, and body envelope violations are not acceptable in the Israelitecommunity. The concept of an innate moral law finds some support inobservations that moral sensibility and reasoning are affected by braindamage, and that emotions themselves are both neurally embodied and thebasis of moral judgement (Greene et al., 2001). The role of emotions inmorality is also supported by psychosocial research that shows thatemotional responses are better predictors of moral judgements than rationalprocesses (Haidt et al., 1993), and that disgust emerges when someone comesto believe that certain acts are moral violations (Rozin et al., 1997).
This brief review of the literature on disgust and morality leads me to thefollowing, very tentative, conclusions:
1. Natural moral law suggests that human morality is a universal, innateproperty of human nature. Whether this moral sensibility has a divine originor is merely a function of natural selection acting on random variations isat present a matter of worldview. However, its universality and inherentlack of compulsion is certainly consistent with the beliefs of manyreligious traditions that morality has a supernatural origin.
2. Morality is fundamentally expressed and controlled through emotions,especially disgust.
3. Because disgust responses are elaborated in community, and serve tomaintain cultural identity, morality is a fundamentally relational, notmerely individual, characteristic of human nature. This implies thatmorality cannot be understood in terms of abstract, absolute, rationallyderived principles, but is rooted in human relationship and emotionalconnection.
4. If we are embodied unities (Jeeves, 1997), morality will be instantiatedin neural circuits in the brain. The emotional aspects of morality havealready been shown to be so embodied.
5. Since disgust and its role in morality is experientially elaborated, itis predicted that the neural systems involved are dynamic, and should showsome plasticity over the lifespan.
Embodied morality: Directions for the future
There is obviously considerable theoretical and empirical work yet to bedone before we have anything near a complete understanding of disgust andmorality, let alone the relationships between other emotions and morality,and ultimately a nuanced analysis of human morality in general. This essayis, of necessity, an extremely sketchy review of general ideas andconnections. I highlight here just a few of the problems and questions thatneed to be addressed.
First, as noted earlier, the concept of natural moral law, while helpful inexposing interconnections among spiritual, psychological and neurobiologicalaspects of morality, has its own problems. We run the risk of trivializingthe roles of faith traditions and communities when we argue that humannature is inherently moral and has universal access to divine moral law.Further, a Jewish colleague reminded me that the terms translated “disgust”and “unclean” in Jewish tradition may not map directly onto the concept ofdisgust presented here and developed further in Rozin and Haidt’s work(Samuel Spero, personal communication, June 5, 2001). A balanced andnuanced articulation of natural moral law is needed before we canappropriately relate it to other perspectives on disgust and morality.
Second, while disgust triggers seem “natural” to members of a particulargroup, and we are rarely consciously aware of how disgust helps us tomaintain moral purity and cultural identity, on occasion people appeal todisgust as a touchstone against which we ought to judge the morality ofparticular things. For example, in response to an article on homosexuality(Looy, 1995), I received anonymously a clipping with the following quote:”…the feelings of disgust normal people feel upon hearing descriptions ofsuch things are normally strengthened by family, religion, and educationalinfluences, thereby preventing many people from succumbing to the temptationto commit unnatural acts” (Anonymous, 1987). This approach reverses therelationship between disgust and morality that has been articulated bysocial scientists. Instead of coming to feel disgust for those thingsdeemed, on the basis of other criteria, morally threatening, disgust is usedas the basis for determining what is immoral. Is this an appropriate use ofdisgust? The obvious cross-cultural diversity of disgust triggers, and thefact that disgust responses must be learned strongly suggest the answer is”no”. However, if morality is innate, and if that innate morality includesknowledge of divine moral “laws”, and if disgust enables us to obey thosemoral laws, then disgust might indeed be a signal for immorality, instead ofsolely a response. This is a potentially dangerous argument that can berefuted only through careful, systematic theoretical and empirical studiesof natural moral law and the role of disgust.
Therefore we need theologians and philosophers to further explore naturalmoral law. They should also address some of the normative questions thatarise from this research: For example, in what ways might disgust distortour moral sensibility? Ought disgust to be considered a “God-given” traitthat ideally plays a part in the development of our morality and identity inparticular historical and cultural contexts? Social scientists couldcontribute to this enterprise by examining the function of disgust in moralevaluations and its role in mediating individual well being and culturalidentity. Psychologists could trace the co-development of disgust withmoral evaluations and reasoning. Further, the neurobiological links amongmoral evaluations, moral reasoning, emotional, rational, and perceptualprocesses need much more extensive exploration, using techniques such asimaging, brain lesion studies, event-related potentials (ERPs),electroencephalography (EEG), and correlations among developmentaldisorders, psychopathological conditions, and morality. Tracing the neuralsystems involved will modify theological and social scientific theoriesabout disgust and morality, and provide some clues regarding their roots,purpose, and embodied character. Inclusion of possible autonomic, endocrineand immune involvement in disgust and morality would extend ourunderstanding of embodied morality beyond the brain and might identifyphysiological consequences of particular patterns of moral responding.
Our understanding of disgust and morality is in its infancy, yettechnological advances in neurobiology, an increasing willingness to engagein interdisciplinary dialogue, to take religion seriously as a dimension ofhuman nature and experience, and growing knowledge of cultural differences,have created a climate within which a breakthrough in our understanding ofmorality could soon occur. A key element, in my view, is a willingness toconsider a multidimensional and unified, rather than a simplereductionistic, view of human nature (see Ashbrook, 1997; Brown, Murphy &
Maloney, 1998). I firmly believe that such interdisciplinary dialogue willcontribute substantively to a rich, nuanced picture of human morality thatdoes justice to its spiritual, relational, psychological, and physiologicaldimensions and its experiential complexity.
Adolphs, R., Damasio, H., Tranel, D. & Damasio, A. (1996). Cortical systemsfor the recognition of emotion in facial expressions. The Journal ofNeuroscience, 16(23), 7678-7687.
Anderson, R. S. (1998). On being human: The spiritual saga of a creaturelysoul. In W. S. Brown, N. Murphy & H. N. Maloney (Eds.), Whatever happenedto the soul? Scientific and theological portraits of human nature.Minneapolis: Augsburg Fortress.
Anonymous (February, 1987). Untitled, excerpt. Fidelity, 23.
Ashbrook, J. B. (1997). ‘Mind’ as humanizing the brain: Toward aneurobiology of meaning. Zygon, 32(3), 301-320.
Brown, W. S. (1998). Cognitive contributions to soul. In W. S. Brown, N.Murphy & H. N. Maloney (Eds.), Whatever happened to the soul? Scientificand theological portraits of human nature. Minneapolis: Augsburg Fortress.
Brown, W. S., Murphy, N. & Malony, H. N. (Eds.). (1998). Whatever happenedto the soul? Scientific and theological portraits of human nature.Minneapolis, Minnesota: Augsburg Fortress.
Calder, A. J., Keane, J., Manes, F., Antoun, N. & Young, A. W. (2000).Impaired recognition and experience of disgust following brain injury.Nature Neuroscience, 3(11), 1077-1078.
Canli, T., Desmond, J. E., Zhao, Z., Glover, G. & Gabrieli, J. D. (1998).Hemispheric asymmetry for emotional stimuli detected with fMRI.Neuroreport, 9(14), 3233-3239.
Cosmides, L. & Tooby, J. (2000). Evolutionary psychology and the emotions.In M. Lewis & J. M. Haviland-Jones (Eds.), Handbook of emotions. New York:Guildford. [On-line]“. Republication for commercial purposes in print or electronic format equires the permissio