Don't Look, Don't Touch, Don't Eat: The Science Behind Revulsion

by Valerie Curtis

  51. P. Rozin, M. Markwith, and C. Stoess, “Moralization and Becoming a Vegetarian: The Transformation of Preferences into Values and the Recruitment of Disgust,” Psychological Science 8 (1997).

  52. P. J. de Jong et al., “Disgust and Sexual Problems—Theoretical Conceptualization and Case Illustrations,” International Journal of Cognitive Therapy 3, no. 1 (2010); C. Borg, P. J. de Jong, and W. W. Schultz, “Vaginismus and Dyspareunia: Automatic vs. Deliberate Disgust Responsivity,” Journal of Sexual Medicine 7, no. 6 (2010).

  53. De Jong et al., “Disgust and Sexual Problems.”

  54. S. Fry and U. Blumenbach, Paperweight (London: Arrow, 2004).

  55. W. O. Monteiro et al., “Anorgasmia from Clomipramine in Obsessive Compulsive Disorder: A Controlled Trial,” British Journal of Psychiatry 151 (1987).

  56. R. Sprengelmeyer et al., “Disgust in Pre-Clinical Huntington’s Disease: A Longitudinal Study,” Neuropsychologia 44, no. 4 (2006).

  57. C. May-Chahal and R. Antrobus, “Engaging Community Support in Safeguarding Adults from Self-Neglect,” British Journal of Social Work 42 (2011).

  58. T. Dalgleish and M. J. Power, “Emotion-Specific and Emotion-Non-Specific Components of Posttraumatic Stress Disorder (PTSD): Implications for a Taxonomy of Related Psychopathology,” Behaviour Research and Therapy 42 (2004).

  59. B. O. Olatunji et al., “Mental Pollution and PTSD Symptoms in Victims of Sexual Assault: A Preliminary Examination of the Mediating Role of Trauma-Related Cognitions,” Journal of Cognitive Psychotherapy 22, no. 1 (2008).

  60. De Jong et al., “Disgust and Sexual Problems.”

  61. P. J. de Jong and M. L. Peters, “Sex and the Sexual Dysfunctions: The Role of Disgust and Contamination Sensitivity,” in Disgust and Its Disorders: Theory, Assessment, and Treatment, ed. B. O. Olatunji and D. McKay (Washington, DC: American Psychological Association, 2009).

  62. Tolin, Worhunsky, and Maltby, “Sympathetic Magic.”

  63. De Jong et al., “Disgust and Sexual Problems.”

  64. Rubio-Godoy, Aunger, and Curtis, “Serotonin.”

  65. De Barra, “Attraction and Aversion.”

  66. M. Ridley, The Origins of Virtue (London: Viking, 1996); R. Wright, The Moral Animal: Why We Are the Way We Are; The New Science of Evolutionary Psychology (London: Vintage, 1995); J. Haidt, The Happiness Hypothesis: Putting Ancient Wisdom and Philosophy to the Test of Modern Science (London: Heinemann, 2007); Joyce, Evolution of Morality.

  67. Jonathan Haidt, in his book The Righteous Mind: Why Good People Are Divided by Politics and Religion, points out that the Right focuses on the broad domain of morality in general, while the Left tends to be concerned much more closely with the rights of minorities. He suggests that it is time for the Left to reappropriate discussion of the big moral issues facing the majority about how it is best that we live.

  68. Y. Inbar et al., “Disgust Sensitivity Predicts Intuitive Disapproval of Gays,” Emotion 9, no. 3 (2009); K. Shanmugarajah et al., “The Role of Disgust Emotions in the Observer Response to Facial Disfigurement,” Body Image 9 (2012); de Barra, “Attraction and Aversion.”

  69. D. Livingstone-Smith, Less Than Human: Why We Demean, Enslave and Exterminate Others (New York: St. Martin’s Press, 2011).

  70. V. Curtis, “The Dangers of Dirt: Household Hygiene and Health” (PhD diss., Wageningen Agricultural University, 1998). Steven Pinker has recently argued that one of the reasons for the decline in violence in recent history is the advance in hygiene. He suggests that it was easier to visit violence on someone who was repulsively dirty. S. Pinker, The Better Angels of Our Nature: Why Violence Has Declined (New York: Penguin Books, 2011).

  71. K. E. Taylor, Cruelty: Human Evil and the Human Brain (Oxford: Oxford University Press, 2009).

  72. J. Charteris-Black, “Britain as a Container: Immigration Metaphors in the 2005 Election Campaign,” Discourse and Society 17, no. 5 (2006); S. I. Wilkinson, Votes and Violence: Electoral Competition and Ethnic Riots in India (Cambridge: Cambridge University Press, 2006).

  73. Livingstone-Smith, Less Than Human.

  74. L. Kass, “The Wisdom of Repugnance,” New Republic 216, no. 22 (1997).

  75. There is a major philosophical argument about whether one can determine what “ought to be” from what “is.” I’m with Sam Harris, that we have an obligation to investigate the conditions that can enhance the flourishing of conscious beings. Harris, Moral Landscape. On moral progress, see also Steven Pinker’s masterwork on the decline of violence: The Better Angels of Our Nature (London: Penguin, 2011).

  76. P. Singer, The Expanding Circle: Ethics and Sociobiology (New York: Farrar, Straus and Giroux, 1981).

  77. Livingstone-Smith, Less Than Human.

  Epilogue

  1. One of the reasons why psychology can’t advance in the way that other sciences have is its continued failure to pin down and agree on its fundamental units of analysis—in brains or behavior. R. Aunger and V. Curtis, “Kinds of Behaviour,” Biology and Philosophy 23, no. 3 (2008): 317–45.

  2. Segerstråle, Defenders of the Truth; Laland and Brown, Sense and Nonsense.

  3. There may of course be rare exceptions. Perhaps some extremophiles, animals in isolated niches where there is no competition from parasites, or animals with powerful physiological armor can do away with the need for behavioral avoidance of parasites.

  4. Of course, the ways in which our living relative species “do” disgust will be quite varied, since many years have gone by for modifications to accumulate on each branch of the tree since the last common ancestor.

  5. Borg, Lieberman, and Kiehl, “Infection, Incest, and Iniquity”; Lieberman, Tooby, and Cosmides, “Human Kin Detection”; J. M. Tybur, D. Lieberman, and V. Griskevicius, “Microbes, Mating, and Morality: Individual Differences in Three Functional Domains of Disgust,” Journal of Personality and Social Psychology 97, no. 1 (2009).

  6. Marsiglio, “Attitudes toward Homosexual Activity.”

  7. Isaksen, “Toward a Sociology of (Gendered) Disgust Images”; Ariely, Predictably Irrational; Shanmugarajah et al., “Role of Disgust Emotions.”

  8. B. Charlton, Psychiatry and the Human Condition (Oxford: Radcliffe Medical Press, 2000).

  9. The approach is set out in more detail in Aunger and Curtis, “Kinds of Behaviour.”

  10. It’s been proposed that men roll away after sex so as not get too high a dose of pair-bond-promoting oxytocin.

  11. For example, components of the love system might include striving to be with the object of affection, sacrificing individual needs for the sake of the other, vigilance for rivals and chasing them away, and threatening serious consequences should a partner stray. Factor Analysis (and, eventually, high-resolution brain scanning) could help to distinguish the subcomponents of the love adaptive system.

  BIBLIOGRAPHY

  Aeby, G. S. “Trade-Offs for the Butterflyfish, Chaetodon multicinctus, When Feeding on Coral Prey Infected with Trematode Metacercariae.” Behavioral Ecology and Sociobiology 52 (2002): 158–65.

  Alio, A. P., L. Merrell, K. Roxburgh, H. B. Clayton, P. J. Marty, L. Bomboka, S. Traoré, and H. M. Salihu. “The Psychosocial Impact of Vesico-Vaginal Fistula in Niger.” Archives of Gynecology and Obstetrics 284 (2011): 1–8.

  Angyal, A. “Disgust and Related Aversions.” Journal of Abnormal and Social Psychology 36 (1941): 393–412.

  Arens, W. The Man-Eating Myth: Anthropology and Anthropophagy. Oxford: Oxford University Press, 1979.

  Ariely, D. Predictably Irrational: The Hidden Forces That Shape Our Decisions. London: HarperCollins, 2008.

  Aunger, R. “Are Food Avoidances Maladaptive in the Ituri Forest of Zaire?” Journal of Anthropological Research 50 (1994): 277–310.

  Aunger, R., and V. Curtis. “Kinds of Behaviour.” Biology and Philosophy 23, no. 3 (2008): 317–45.

  Banbura, J., P. Perret, J. Blondel, A. Sauvages, M. J. Galan, and M. M. Lambrechts. “Sex Differences in Parental Care in a Corsican Blue Tit Parus cae
ruleus Population.” Ardea 89, no. 3 (2001): 517–26.

  Baumeister, R. F., K. D. Vohs, and C. Nathan DeWall. “How Emotion Shapes Behavior: Feedback, Anticipation, and Reflection, Rather Than Direct Causation.” Personality and Social Psychology Review 11, no. 2 (2007): 167–203.

  Behringer, D. C., M. J. Butler, and J. D. Shields. “Avoidance of Disease by Social Lobsters.” Nature 441 (2006): 421.

  Blair, R. H., and B. W. Tucker. “Nest Sanitation.” British Birds 34 (1941): 206–15.

  Borg, C., P. J. de Jong, and W. W. Schultz. “Vaginismus and Dyspareunia: Automatic vs. Deliberate Disgust Responsivity.” Journal of Sexual Medicine 7, no. 6 (2010): 2149–57.

  Borg, J., D. Lieberman, and K. A. Kiehl. “Infection, Incest, and Iniquity: Investigating the Neural Correlates of Disgust and Morality.” Journal of Cognitive Neuroscience 20, no. 9 (2008): 1529–46.

  Bourdieu, P. “Social Space and Symbolic Power.” Sociological Theory 7, no. 1 (1989): 14–25.

  Bowles, S., and H. Gintis. A Cooperative Species: Human Reciprocity and Its Evolution. Princeton, NJ: Princeton University Press, 2011.

  Bradley, M., and K. Stow, eds. Rome, Pollution and Propriety: Dirt, Disease and Hygiene in the Eternal City from Antiquity to Modernity. Cambridge: Cambridge University Press, 2012.

  Brashares, J. S., and P. Arcese. “Scent Marking in a Territorial African Antelope: II. The Economics of Marking with Faeces.” Animal Behaviour 57, no. 1 (1999): 11–17.

  Brian, A., W.-P. Schmidt, D. Rajaraman, K. Shankar, R. Aunger, and V. Curtis. “Superamma: A Cluster Randomized Trial of a Village-Level Intervention to Promote Handwashing with Soap in Rural Andhra Pradesh, India.” Unpublished manuscript, 2013. Microsoft Word file.

  British Heart Foundation. “Give Up before You Clog Up.” Edited by UK Department of Health, 2003. Advertisement on You-Tube, http://www.youtube.com/watch?v=cDAN7Oi62e0.

  Brown, D. E. Human Universals. New York: McGraw-Hill, 1991.

  Brown, G. E., D. P. Chivers, and R. J. F. Smith. “Localized Defecation by Pike: A Response to Labelling by Cyprinid Alarm Pheromone?” Behavioral Ecology and Sociobiology 36, no. 2 (1995): 105–10.

  Carter, S. L. Civility: Manners, Morals, and the Etiquette of Democracy. New York: Basic Books, 1998.

  Cashdan, E. “Adaptiveness of Food Learning and Food Aversions in Children.” Social Science Information 37, no. 4 (1998): 613–32.

  Chaisson, E. J. “Energy Rate Density as a Complexity Metric and Evolutionary Driver.” Complexity 16, no. 3 (2011): 27–40.

  Chapman, H. A., D. A. Kim, J. M. Susskind, and A. K. Anderson. “In Bad Taste: Evidence for the Oral Origins of Moral Disgust.” Science 323, no. 5918 (2009): 1222.

  Charlton, B. Psychiatry and the Human Condition. Oxford: Radcliffe Medical Press, 2000.

  Charteris-Black, J. “Britain as a Container: Immigration Metaphors in the 2005 Election Campaign.” Discourse and Society 17, no. 5 (2006): 563–81.

  Clark, L., and J. R. Mason. “Use of Nest Material as Insecticidal and Anti-Pathogenic Agents by the European Starling.” Oecologia 67, no. 2 (1985): 169–76.

  Clayton, D. H. “Coevolution of Avian Grooming and Ectoparasite Avoidance.” In Bird-Parasite Interactions: Ecology, Evolution, and Behaviour, edited by J. E. Loye and M. Zuk, 258–89. Oxford: Oxford University Press, 1991.

  Cochran, G., and H. Harpending. The 10,000 Year Explosion: How Civilization Accelerated Human Evolution. New York: Basic Books, 2010.

  Corbin, A. The Foul and the Fragrant: Odor and the French Social Imagination. Cambridge, MA: Harvard University Press, 1988.

  Cremer, S., S. A. O. Armitage, and P. Schmid-Hempel. “Social Immunity.” Current Biology 17, no. 16 (2007): R693–702.

  Crofts, T., and J. Fisher. “Menstrual Hygiene in Ugandan Schools: An Investigation of Low-Cost Sanitary Pads.” https://dspace.lboro.ac.uk/dspace-jspui/handle/2134/9399, 2012.

  Curno, O., J. M. Behnke, A. G. McElligott, T. Reader, and C. J. Barnard. “Mothers Produce Less Aggressive Sons with Altered Immunity When There Is a Threat of Disease during Pregnancy.” Proceedings of the Royal Society of London B 276, no. 1659 (2009): 1047–54.

  Curtis, V. “Dirt, Disgust and Disease: A Natural History of Hygiene.” Journal of Epidemiology and Community Health 61, no. 8 (2007): 660–64.

  Curtis, V., R. Aunger, and T. Rabie. “Evidence That Disgust Evolved to Protect from Risk of Disease.” Proceedings of the Royal Society B 271, supplement 4 (2004): S131–33.

  Curtis, V., and A. Biran. “Dirt, Disgust, and Disease: Is Hygiene in Our Genes?” Perspectives in Biology and Medicine 44, no. 1 (2001): 17–31.

  Curtis, V. A., A. Biran, K. Deverell, C. Hughes, K. Bellamy, and B. Drasar. “Hygiene in the Home: Relating Bugs to Behaviour.” Social Science and Medicine 57, no. 4 (2003): 657–72.

  Curtis, V., and S. Cairncross. “Effect of Washing Hands with Soap on Diarrhoea Risk in the Community: A Systematic Review.” Lancet Infectious Diseases 3 (2003): 275–81.

  Curtis, V., L. Danquah, and R. Aunger. “Planned, Motivated and Habitual Hygiene Behaviour: An Eleven Country Review.” Health Education Research 24, no. 4 (2009): 655–73.

  Curtis, V., M. de Barra, and R. Aunger. “Disgust as an Adaptive System for Disease Avoidance Behaviour.” Philosophical Transactions of the Royal Society B 366 (2011): 389–401.

  Curtis, V., B. Kanki, T. Mertens, T. Traore, I. Diallo, F. Tall, and S. Cousens. “Potties, Pits and Pipes: Explaining Hygiene Behaviour in Burkina Faso.” Social Science and Medicine 41, no. 3 (1995): 383–93.

  Curtis, V., W. Schmidt, S. Luby, R. Florez, O. Touré, and A. Biran. “Hygiene: New Hopes, New Horizons.” Lancet Infectious Diseases 11, no. 4 (2011): 312–21.

  Dahle, R. “Lukt, fukt og skam” (Bodily smells, wetness and shame). Paper presented at Norsk Selskap for Aldersforskning, Oslo, September 9, 1999.

  Dalgleish, T., and M. J. Power. “Emotion-Specific and Emotion-Non-Specific Components of Posttraumatic Stress Disorder (PTSD): Implications for a Taxonomy of Related Psychopathology.” Behaviour Research and Therapy 42 (2004): 1069–88.

  Damasio, A. R. Descartes’ Error: Emotion, Reason and the Human Brain. New York: Putnam, 1994.

  Darwin, C. The Expression of the Emotions in Man and Animals. 1872. Reprint. Chicago: University of Chicago Press, 1965.

  Davey, G. C. L., G. Buckland, B. Tantow, and R. Dallos. “Disgust and Eating Disorders.” European Eating Disorders Review 6, no. 3 (1998): 201–11.

  Davey, G. C. L., McDonald, U. Hirisave, C. G. Prabhu, S. Iwawaki, I. J. Ching, H. Merckelbach, P. J. de Jong, P. W. L. Leung, and B. C. Reimann. “A Cross-Cultural Study of Animal Fears.” Behaviour Research and Therapy 36 (1998): 735–50.

  David, B., and B. O. Olatunji. “The Effect of Disgust Conditioning and Disgust Sensitivity on Appraisals of Moral Transgressions.” Personality and Individual Differences 50, no. 7 (2011): 1142–46.

  Dawkins, R. The Selfish Gene. New York: Oxford University Press, 1976.

  . Unweaving the Rainbow. London: Allen Lane, 1998.

  De Barra, M. “Attraction and Aversion: Pathogen Avoidance Strategies in the UK and Bangladesh.” PhD diss., London School of Hygiene and Tropical Medicine, 2011.

  Decaestecker, E., L. De Meester, and D. Ebert. “In Deep Trouble: Habitat Selection Constrained by Multiple Enemies in Zoo-plankton.” Proceedings of the National Academy of Sciences USA 99, no. 8 (2002): 5481–85.

  De Jong, P. J., and M. L. Peters. “Sex and the Sexual Dysfunctions: The Role of Disgust and Contamination Sensitivity.” In Disgust and Its Disorders: Theory, Assessment, and Treatment, ed. B. O. Olatunji and D. McKay, 253–70. Washington, DC: American Psychological Association, 2009.

  De Jong, P. J., J. van Lankveld, H. J. Elgersma, and C. Borg. “Disgust and Sexual Problems—Theoretical Conceptualization and Case Illustrations.” International Journal of Cognitive Therapy 3, no. 1 (2010): 23–39.

  Dethier, V. G. The World of the Tent-Makers: A Natural History of the Eastern Tent Caterpillar. Amherst: Unive
rsity of Massachusetts Press, 1980.

  Diamond, J. M. “Archaeology: Talk of Cannibalism.” Nature 407, no. 6800 (2000): 25–26.

  Diehl-Fleig, E., and M. E. Lucchese. “Reações comportamentais de operárias de Acromyrmex striatus (Hymenoptera, Formicidae) na presença de fungos entomopatogênicos.” Revista Brasileira de Entomologia 35 (1991): 101–7.

  Douglas, M. Purity and Danger: An Analysis of Concepts of Pollution and Taboo. London: Routledge, 2003.

  Duncan, L. A., and M. Schaller. “Prejudicial Attitudes toward Older Adults May Be Exaggerated When People Feel Vulnerable to Infectious Disease: Evidence and Implications.” Analyses of Social Issues and Public Policy 9, no. 1 (2009): 97–115.

  Durham, W. H. Coevolution: Genes, Culture and Human Diversity. Stanford, CA: Stanford University Press, 1991.

  Earle, S. “Factors Affecting the Initiation of Breastfeeding: Implications for Breastfeeding Promotion.” Health Promotion International 17, no. 3 (2002): 205.

  Ehrlich, P. R., D. S. Dobkin, and D. Wheye. “The Adaptive Significance of Anting.” Auk 103, no. 4 (1986): 835.

  Eisner T., E. van Tassell, and J. E. Carrel. “Defensive Use of a ‘Fecal Shield’ by a Beetle Larva.” Science 158 (1967): 1471–73.

  Elias, N. The Civilizing Process. 1939. Translated by E. Jephcott. Malden, MA: Blackwell, 2000.

  Emerson, P. M., S. Cairncross, R. L. Bailey, and D. C. W. Mabey. “A Review of the Evidence for the ‘F’ and ‘E’ Components of the SAFE Strategy for Trachoma Control.” Tropical Medicine and International Health 5, no. 8 (2000): 515–27.

  Eskine, K. J., N. A. Kacinik, and J. J. Prinz. “A Bad Taste in the Mouth.” Psychological Science 22, no. 3 (2011): 295.

  Evans, D. B., and S. F. Hurley. “The Application of Economic Evaluation Techniques in the Health Sector: The State of the Art.” Journal of International Development 7, no. 3 (1995): 503–24.

  Fayard, J. V., A. K. Bassi, D. M. Bernstein, and B. W. Roberts. “Is Cleanliness Next to Godliness? Dispelling Old Wives’ Tales: Failure to Replicate Zhong and Liljenquist (2006).” Journal of Articles in Support of the Null Hypothesis 6, no. 2 (2009): 21–28.