We are prejudiced against all kinds of other people, based on superficial physical features: We react negatively to facial disfigurement; we avoid sitting next to people who are obese, or old, or in a wheelchair; we favor familiar folks over folks that are foreign. (…)

It makes immediate sense that people would develop aversions against people who actually have infectious diseases. But why does it also lead to these aversions to perfectly healthy people? Because it’s impossible to directly detect the presence of bacteria and viruses and other microscopic parasites; and so we’re forced to use crude superficial cues. Consequently, we make mistakes. Some of those mistakes lead to the irrational avoidance of things (including people) that pose no infection risk at all.

Here’s an example: Animal feces is loaded with parasites that can make you ill. So if something looks like a pile of dog poop, you probably won’t eat it. That’s smart. But what if I took some delicious chocolate fudge and molded it into the shape of poop? Research by Paul Rozin and his colleagues shows that a lot of people still won’t eat it – even though they know it’s fudge! These people aren’t responding to any rational appraisal of infection risk; they are responding – automatically and aversively – to appearances.

The same principle applies in our interactions with other people.

{ Scientific American | Continue reading }

photo { Nicolas Silberfaden }

health, photogs, psychology, relationships | June 14th, 2011