AFFIRMATIVE ACTION is back before the Supreme Court today. The court has agreed to hear, for the second time, the case of Abigail Fisher, a white applicant who claims that she was rejected by the University of Texas at Austin because of her race. Ms. Fisher invokes the promise of equal protection contained in the 14th Amendment, reminding us that judging people by their ancestry, rather than by their merits, risks demeaning their dignity.
Upholding affirmative action in 2003, in Grutter v. Bollinger, Justice Sandra Day O’Connor argued that it served the intellectual purpose of a university. Writing for the majority, she described how the University of Michigan aspired to enhance diversity not only to improve the prospects of certain groups of students, but also to enrich everyone’s education.
Ms. Fisher argues that diversity may be achieved in other ways, without considering race. Before resorting to the use of race or ethnicity in admissions, the University of Texas must offer “actual evidence, rather than overbroad generalizations about the value of favored or disfavored groups” to show that “the alleged interest was substantial enough to justify the use of race.”
Our research provides such evidence. Diversity improves the way people think. By disrupting conformity, racial and ethnic diversity prompts people to scrutinize facts, think more deeply and develop their own opinions. Our findings show that such diversity actually benefits everyone, minorities and majority alike.
To study the effects of ethnic and racial diversity, we conducted a series of experiments in which participants competed in groups to find accurate answers to problems. In a situation much like a classroom, we started by presenting each participant individually with information and a task: to calculate accurate prices for simulated stocks. First, we collected individual answers, and then (to see how committed participants were to their answers), we let them buy and sell those stocks to the others, using real money. Participants got to keep any profit they made.
When trading, participants could observe the behavior of their counterparts and decide what to make of it. Think of yourself in similar situations: Interacting with others can bring new ideas into view, but it can also cause you to adopt popular but wrong ones.
We assigned each participant to a group that was either homogeneous or diverse (meaning that it included at least one participant of another ethnicity or race). To ascertain that we were measuring the effects of diversity, not culture or history, we examined a variety of ethnic and racial groups. In Texas, we included the expected mix of whites, Latinos and African-Americans. In Singapore, we studied people who were Chinese, Indian and Malay. (The results were published with our co-authors, Evan P. Apfelbaum, Mark Bernard, Valerie L. Bartelt and Edward J. Zajac.)
The findings were striking. When participants were in diverse company, their answers were 58 percent more accurate. The prices they chose were much closer to the true values of the stocks. As they spent time interacting in diverse groups, their performance improved.
In homogeneous groups, whether in the United States or in Asia, the opposite happened. When surrounded by others of the same ethnicity or race, participants were more likely to copy others, in the wrong direction. Mistakes spread as participants seemingly put undue trust in others’ answers, mindlessly imitating them. In the diverse groups, across ethnicities and locales, participants were more likely to distinguish between wrong and accurate answers. Diversity brought cognitive friction that enhanced deliberation.
For our study, we intentionally chose a situation that required analytical thinking, seemingly unaffected by ethnicity or race. We wanted to understand whether the benefits of diversity stem, as the common thinking has it, from some special perspectives or skills of minorities.
What we actually found is that these benefits can arise merely from the very presence of minorities. In the initial responses, which were made before participants interacted, there were no statistically significant differences between participants in the homogeneous or diverse groups. Minority members did not bring some special knowledge.
The differences emerged only when participants began interacting with one another. When surrounded by people “like ourselves,” we are easily influenced, more likely to fall for wrong ideas. Diversity prompts better, critical thinking. It contributes to error detection. It keeps us from drifting toward miscalculation.
Our findings suggest that racial and ethnic diversity matter for learning, the core purpose of a university. Increasing diversity is not only a way to let the historically disadvantaged into college, but also to promote sharper thinking for everyone.
When it comes to diversity in the lecture halls themselves, universities can do much better. A commendable internal study by the University of Texas at Austin showed zero or just one African-American student in 90 percent of its typical undergraduate classrooms. Imagine how much students might be getting wrong, how much they are conforming to comfortable ideas and ultimately how much they could be underperforming because of this.
Ethnic diversity is like fresh air: It benefits everybody who experiences it. By disrupting conformity it produces a public good. To step back from the goal of diverse classrooms would deprive all students, regardless of their racial or ethnic background, of the opportunity to benefit from the improved cognitive performance that diversity promotes.