Individual Differences in Sympathetic Magical Beliefs

Individual Differences in Sympathetic Magical Beliefs

There are large individual differences in the extent of sympathetic magical thinking both within and between cultures. Of the 36 participants in the study on the nature of contagious essence (Nemeroff & Rozin, 1994), 24 displayed dual models—material essence for illness contaminants, and spiritual essence for interpersonal and moral contaminants. However, 6 participants seemed to have a material essence model for everything, including moral contagion; for these subjects, washing was generally effective. Another 6 subjects used a spiritual essence model for everything, so washing or boiling were quite ineffective, even for illness sources.

As well as differences in the quality of contagion, there are large individual variations in contagion sensitivity. Wide variations were demonstrated in American college students and their parents on a scale designed to measure disgust responses to neutral entities after contact with disgusting entities (Rozin, Fallon, & Mandell, 1984).

Another study exploring individual differences examined contagion and similarity thinking about kosher-relevant and -irrelevant contaminations in a sample of Jews of varying levels of orthodoxy (Nemeroff & Rozin, 1992). Generally, it was found that sensitivity to contagion items intercorrelated quite highly with each other, and the same for similarity items, but the two did not correlate substantially with each other. Some individuals were sensitive to contagion but not similarity such that, for example, they would reject a meat dish into which less than 1/60th volume of milk fell, but have no problem eating beef stroganoff made with non-dairy creamer (a similarity item in that the combination appeared nonkosher, but was, in fact, kosher). Other individuals were sensitive to similarity but not contagion. We also developed a series of questionnaire measures of the combined action of both contagion and similarity; for example, a drop of non-dairy creamer falling into a beef stew (“contagion via similarity”). A surprising number of people were put off by even this very weakened magical effect.

More recently, we created a scale of disgust sensitivity, in a more orthodox psychometric framework, including a number of items that deal with similarity and contagion (Haidt, McCauley, & Rozin, 1994). There is very wide variation in sensitivity to disgust, similarity, and contagion in both American and Japanese cultures (Haidt, McCauley, & Rozin, 1994; Imada, Haidt, McCauley, & Rozin, 2000, unpublished data). At extremes in American culture are persons who feel uncomfortable blowing their nose in a piece of brand-new toilet paper, handling money, or sleeping on a laundered pillowcase in a hotel, versus persons who are incredulous that anyone would have such concerns. We created a hands-on validation of this paper-and-pencil disgust scale, using college students (Rozin, Haidt, McCauley, Dunlop, & Ashmore, 1999). These students spent over an hour in the laboratory in a situation in which they were simply asked to indicate whether they would be willing to do 30 tasks; if they agreed, they actually performed the task. An example for similarity magic related to disgust was to present students with a brand-new bed pan, into which the experimenter poured some apple juice from a commercial apple juice bottle. Participants were asked if they would be willing to drink some of the apple juice: only 28% complied. For a typical contagion item, subjects were asked if they would be willing to drink water from a glass after it had been stirred by a used but washed comb; 30% complied. Norms for college students were established for a wide range of negative contagion and similarity situations.

There has been little attention paid to individuals who show minimal sensitivity to magical principles. However, there is a clinical entity, the cleaning variety of obsessive–compulsive disorder (OCD), that seems to represent excessive concern about negative contagion. Appropriately, persons with OCD show high scores on the disgust scale (Tolin, Brigidi, & Foa, 1999), and obsessive–compulsive tendencies in normal persons correlate positively with disgust scale scores (Rozin, Taylor, Ross, Bennett, & Hejmadi, 2000).