Past researchers have found that people of lower cognitive ability are more likely to be prejudiced, but prejudice isn't exclusive to dim bulbs. A new study finds that people at both high and low ends of the intelligence spectrum actually express equal levels of prejudice—the difference is just what they're prejudiced against.
The researchers, social psychologists Mark Brandt and Jarret Crawford, analyzed 5,914 subjects in their experiment, "Answering Unresolved Questions About the Relationship Between Cognitive Ability and Prejudice." Removing value judgments about whether a specific prejudice is justified or not, they measured the amount of prejudice present in groups of higher cognitive ability and lower cognitive ability. They gauged the cognitive ability of their subjects using a wordsum test, which is considered to be correlated to an individual's intelligence quotient (IQ). Brandt and Crawford replicated previous findings that people of low cognitive ability tend to be prejudiced against non-conventional or liberal groups, as well as groups that have "low choice" in their status—groups defined by their race or gender or sexual orientation, for example. According to their research, this tendency inverted among people of high cognitive ability. In other words, the smarter subjects in their study were likely to be prejudiced against groups considered conventional or conservative—groups perceived to have "high choice" in their associations."
"People dislike people who are different from them," Brandt and Crawford said in an interview with Broadly. "Derogating people with different worldviews can help people maintain the validity of their own world view." In other words, if you see the world one way, you may rely on that perspective, so you might reinforce the idea that you're right by believing other worldviews are wrong.
There was another polarized finding in their study. Brandt and Crawford found that people of low cognitive ability are prejudiced against groups that people didn't choose to be part of, such as ethnic or LGBT groups. This is poignant in 2016, a time when conservative communities across the country are unifying around intolerance of transgender people, Muslim Americans continue to face grotesque prejudice, and police brutality is high.
Brandt and Crawford cited prior research that has shown less cognitively capable people often "essentialize," or see different groups as being distinct from each other, with "clear boundaries."
"Having clear boundaries helps people feel like the opposing group is distinct and far away. That is, they won't be so much of a threat," they said. The researchers pointed to a recent study looking at this boundary phenomenon with respect to Donald Trump's stupid plan to build a big wall along the southern border of the United States—it would create a literal boundary where before only a mental one existed.
The conservatives who support this plan are expressing prejudice towards "low-choice" groups—in this case, Mexicans, who were born Mexican and did not choose to be that. "On the flipside, people high in cognitive ability express more prejudice against high-choice groups," such as conservatives, the researchers said. "They may be especially angered by groups that they think should be able to change their minds."