New research finds that the famous Dunning-Kruger Effect extends to the way we think about our own racism and sexism.

"Very prejudiced individuals may be genuinely unaware of their shortcomings because they lack the meta-cognition necessary to perceive them." (Photo: Saul Loeb/AFP/Getty Images)

In 2016, then-presidential candidate Donald Trump famously proclaimed: "I am the least racist person you have ever met." That statement could, of course, be an outright falsehood. But it could also be an example of a prideful man who is motivated to lie to himself.

New research points to a third possibility. It finds that a lot of people underestimate their inherent racism and sexism because they never developed the mental skills required to recognize their own prejudices.

"Egalitarianism can be conceptualized as a skill, or type of confidence," write Keon West of the University of London and Asia Eaton of Florida International University. Looked at in that way, avoiding racism and sexism "is not merely a matter of willingness, but also a matter of ability."

And as with many abilities, we tend to greatly overestimate how good we are at it. That self-delusion is known as the Dunning-Kruger Effect, and since its conception in 1999, it has been applied to a wide variety of domains, from driving skills to the quality of decisions made by physicians.

In the journal Personality and Individual Differences, West and Eaton provide evidence that the Dunning-Kruger Effect also applies to one's ability to remain impartial. They find that the most prejudiced people are also the most likely to underestimate how biased they are.

The first of their studies featured 148 people "recruited through their involvement in a voluntary racism-related diversity-training program aimed at graduate students in London." Just under 80 percent were white.

At the beginning of the program, all participants indicated, on a scale of zero to 99, "how egalitarian you are about race compared to the other people in the program," and compared to other people in the United Kingdom. They also took tests designed to measure their conscious and unconscious racism (the latter was judged using Project Implicit's Black vs. White Implicit Associations Test).

Finally, they took part in a two-hour diversity training session, and then retook the tests to determine if it the training had had a measurable impact.

The researchers report that, on average, "participants rated their racial egalitarianism as being in the 75th percentile," and assumed they were less prejudiced than three-quarters of their peers. "The least egalitarian participants were also the ones that overestimated their egalitarianism the most," they add.

Perhaps most disappointingly, these estimates did not significantly change following diversity training. People largely held onto their inflated self-evaluations.

The second study, featuring 159 people from that same pool, focused on sexism, but was otherwise identically structured. This time, participants on average rated themselves as less sexist than 69 percent of their peers. Replicating the first study's results, the most sexist people were the ones who most overestimated their freedom from gender bias, and diversity training did not move the needle.

West and Eaton argue these findings point to two conclusions. First, "diversity training," as it is currently conducted, is largely ineffective; it needs to include "actual training in techniques to reduce bias."

More fundamentally, "the research suggests that, even if motivational considerations were accounted for, there may be important cognitive hindrances to understanding and reducing [one's] prejudice."

"Very prejudiced individuals may be genuinely unaware of their shortcomings because they lack the meta-cognition necessary to perceive them," the researchers conclude. Creating a prejudice-free world will mean opening hearts, but it may also require re-training brains.