Disgust and morality

Picking up the newspaper is an invitation to an emotional joyride. Last weekend in Austin, for example, the news that the Longhorns had beaten Nebraska led to a collective whoop of joy. Most of the emotions you get from the newspaper are less pleasant, though. News reports about the planning of the attacks in Mumbai, for example, can lead to anger. Reports about child prostitution rings can lead to disgust.

Disgust is the emotion that I want to talk about today.

Current theories suggest that we have to distinguish between affect and emotion. Affect is the feelings that you experience in different situations. As you start to read a harrowing story about child prostitution, you may get a pit in your stomach or feel a bit light-headed. Emotion occurs after you determine the cause of the feelings you are having. This process of finding the causes is called appraisal. So, feeling disgust after reading a news story requires appraising that your ill feeling is being caused by disgust for the events described in the story.

This view of disgust suggests that the emotion of disgust is strongly connected to our sense of morality. That is, when we feel disgust, we should also express feelings of moral outrage. And to counteract those emotions, we should increase our concern with purity.

A paper by E.J. Horberg, Christopher Oveis, Dacher Keltner, and Adam Cohen in the December, 2009 issue of the Journal of Personality and Social Psychology looked at this issue.

First, they looked at the difference between disgust and anger. They had people read about relatively minor violations of purity and violations of justice. A violation of purity might be a story about a brother and sister who like to kiss passionately when nobody is around. A violation of justice might be a person who steals books from the library that other people need to study. People judged how wrong they felt that these violations were. People also rated how angry and disgusted they were feeling. The amount of disgust people were feeling was related to the strength of their ratings of the wrongness of the purity violations. The amount of anger people were feeling was related to the strength of their ratings of the wrongness of the justice violations.

Another study in this series looked at the causal relationship between disgust and moral sense. In this study, people watched a video. For some people, the video was disgusting (the scene from the movie Trainspotting in which the main character has to reach through a toilet filled with feces). For other people, the video was designed to generate sadness (a scene in which a child watches a father's death).

After seeing these videos, people read about a variety of violations of purity and justice (like those I just described). The people who watched the disgusting video found the violations of purity to be much more wrong than the people who watched the sadness video. Neither of these videos had much impact at all on people's judgments of the wrongness of violations of justice.

These studies suggest that there is a tight relationship between our sense of moral purity and the emotion of disgust. Violations of our sense of moral purity lead us to feel the emotion of disgust. When we experience the emotion of disgust, we also change our judgments of the moral purity of others.