White as Snow, Black as Sin: The Colors of Moral Purity and Pollution

What do wedding dresses and doves have to do with toothpaste and soap? Psychologists Gary Sherman and Gerald Clore from the University of Virginia found that the perceptual symbols of purity, such as snow and doves, are associated with the color white and the feeling of cleanliness, while the symbols of immorality are associated with feelings of dirtiness and the color black.

As reported in a recent issue of Psychological Science, a journal of the Association for Psychological Science, people greatly desired products dealing with self-cleanliness after they were invoked with a feeling of immorality.

Using a reaction time test called a Stroop task, researchers measured the time it took participants to decide if a word was moral or immoral when presented in white or black text. Slower reaction times in the Stroop task identify what the psychologists called “cognitive conflict,” or the trouble we have when a word does not match up to the concept associated with it.  When identifying moral words, participants were quicker when the words were written in white than when they were written in black, showing the association of white with virtue and black with sin.

Scientists then had the participants write out a copy of an immoral story and do the task again. Those who hand-copied the unethical version of the story had speedier responses to immoral words and those presented in black, demonstrating the automatic association of immorality with blackness.

The scientists predicted that if immorality leaves a dirty feeling, exposure to an immoral story should increase the desirability for cleaning products. After hand-copying the immoral story, participants showed increased desire specifically for the self-cleansing products of toothpaste and soap when choosing among various cleaning and non-cleaning products. Therefore, the thought of immorality invoked feelings of impurity and dirtiness, sparking people’s desire to cleanse themselves from the moral contamination.

The researchers concluded with the implications of their results on racial prejudice: “[These results] may explain, in part, why stereotypes of dark-skinned people often allude to immorality and poor hygiene, and why the typical criminal is seen as both dark skinned and physically dirty.”