Sensory and Moral Offense: How Disgust Shaped our Diets, and Biased our Moral Judgments
From an evolutionary point of view, disgust is beneficial in helping us stay away – and avoid altogether, items that could cause us illness or disease. But disgust too, serves another important function – it shapes our moral judgments and opinions.
EMOTION SCIENCE ARTICLES
What do you find disgusting? If you’re like most people, you might easily think of objects that trigger a sense of revulsion and distaste. Disgust is considered a ‘food-related’ emotion, a creative yet accurate description of an emotion that has very much to do with our sense of smell and taste. The psychologist who first helped define disgust is one Paul Rozin. He defines disgust as, “Revulsion at the prospect of (oral) incorporation of an offensive object. The offensive objects are contaminants; that is, if they even briefly contact an acceptable food, they tend to render that food unacceptable. [1]” In Rozin’s definition, disgust is therefore an emotion that offends or senses if we so much even think about putting a disgusting contaminant near our mouths. Anything that is disgusting, that comes in contact with an acceptable food item, is going to contaminate and also make disgusting the contacted food. For that reason, disgust also has a ‘contagion’ property; disgusting objects can ‘infect’ other items with toxins, infectious microbes and psychologically offensive qualities.
From an evolutionary point of view, disgust is beneficial in helping us stay away – and avoid altogether, items that could cause us illness or disease. But disgust too, serves another important function – it shapes our moral judgments and opinions. You may have read news of morally offensive acts – rape, murder, incestuous relationships, and labeled some of the perpetrator’s acts as being disgusting. In fact, what started out as an emotion that helps guide our dietary habits and food choices is also used to guide our moral judgements of others. The same properties for biological disgust (also known as core disgust – food/infection-related disgust) are also activated for inedible objects. For instance, would you buy, and wear a leather jacket once worn by a child sex predator if it was offered to you for a modest sum of money? Would you rent or purchase an apartment if the landlord once told you that the very same premises were once used by its former tenants for illicit, drug-fuelled sex acts? You might think twice, or at least hesitate if such information was made known to you.
Our emotions bias our decisions and choices, and the same too, applies to the emotion of disgust. With disgust, in particular, the decisions tend to be shaded by norms and expectations of purity. Disgust is likely to influence decisions that are in some way or another, related to ideals of cleanliness and freedom from disease. This can play out in our judgements of actions considered unusual, or that go against societal norms. In one study, individuals who felt disgusted were more likely to judge individuals different from them (out-group members) more negatively, and felt a greater sense of threat and anxiety towards these out-group members [2]. In another study, psychologists manipulated the odour in a laboratory setting and found that judgments of morally-questionable acts (eating a dead dog, cannibalizing a young child for survival, deriving sexual pleasure from a kitten) were harsher when the room smelt bad, than when it was not [3]. Moral judgements become less severe when there is a sense of ‘embodied’ cleanliness. In another study, individuals who washed their hands with soap gave less harsh judgements towards the same morally-questionable acts above. While the study does not imply that we should all wash our hands in order to be less morally judgmental, it does show that there is indeed an intimate link between disgust and purity, and how these influence judgments of what is right and wrong [4].
Disgust, as an emotion that shaped out diet and eating habits, has also been used by evolutionary forces to help us arrive at intuitive conclusions about the morality of certain actions and behaviours. As with how emotions guide our decisions, it pays to be aware of how our underlying emotion-cognition link shapes our decisions and judgments of others, and of their actions.
Reference:
[1] Rozin, P., & Fallon, A. E. (1987). A perspective on disgust. Psychological Review, 94(1), 23-41.
[2] Hodson, G., Choma, B. L., Boisvert, J., Hafer, C. L., MacInnis, C. C., & Costello, K. (2013). The role of intergroup disgust in predicting negative outgroup evaluations. Journal of Experimental Social Psychology, 49(2), 195-205.
[3] Schnall, S., Haidt, J., Clore, G. L., & Jordan, A. H. (2008). Disgust as embodied moral judgment. Personality and Social Psychology Bulletin, 34(8), 1096-1109.
[4] Schnall, S., Benton, J., & Harvey, S. (2008). With a clean conscience: Cleanliness reduces the severity of moral judgments. Psychological Science, 19(12), 1219-1222.
