Cleanliness Is Next to Priggishness

We like to think that our opinions are based on reason. We’ve thought something through and arrived at a conclusion. We’re not easily swayed, overly emotional, or wildly inconsistent. We are more or less rational. 

But maybe we’re fooling ourselves. A new study titled “A Clean Self Can Render Harsh Moral Judgment” found that opinions on social issues like pornography, adultery, and drugs were affected by whether people had washed their hands prior to being asked. Participants were told to rate their feelings on social issues, like the ones mentioned above, on an 11-point scale from “very immoral” to “very moral.” Those who lathered up beforehand were significantly more likely than those with grubby palms to find, say, profane language immoral.

In a second experiment, some participants were simply told to think of phrases like “My hair feels clean and light. My breath is fresh. My clothes are pristine and like new.” Meanwhile, another group was told to think “My hair feels oily and heavy. My breath stinks. I can see oil stains and dirt all over my clothes.” The groups were then asked, using the same 11-point scale, to rate the morality of abortion, homosexuality, and masturbation. Those who had been thinking clean thoughts were more likely to deem those practices immoral.

One of the two researchers who carried out this study, Chen-Bo Zhong, published a paper in 2006 about the “Macbeth Affect”—that is, the finding that washing your hands “alleviates the upsetting consequences of unethical behavior and reduces threats to one’s moral self-image.” You really can, the authors concluded, wash your sins away. But this new research is, in some ways, more disturbing. From the paper:

We deem this form of magical thinking potentially negative: The changes observed in our moral judgment were not based on rational reasoning or realistic alteration to one’s moral standing, but the outcome of metaphorical thinking that confuses physical purity with moral purity.

One thing to note is that the participants in this study, like the participants in so many other university studies, were undergraduates. Perhaps people in their late teens/early twenties are more suggestible than their grizzled elders.  Or maybe that’s just magical thinking, too.

**UPDATE: One of the paper’s authors wrote in to say that one of the three experiments involved participants other than undergrads, which I should have noted. Also, I neglected to include the third author of the paper, Niro Sivanathan. Sorry about that.

(The study, published in the Journal of Experimental Social Psychology, was conducted by Chen-Bo Zhong,  Brendan Strejcek, and Niro Sivanathan.)

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