Perhaps Mr. Noll’s identity shouldn’t have mattered. His historical evidence and the power of his arguments would be worth considering even if he were Catholic, Jewish or secular. But his identity did matter. It mattered because my evangelical students could not simply assume bad faith on the author’s part. They knew Mr. Noll cared about evangelicals as a group of people. Instead of dismissing Mr. Noll as a bigot, my students thoughtfully engaged with his work.

Since then, I have taken identity into account every time I have assigned new books for one of my courses. I currently teach a course called Black Intellectuals, which is focused on debates around racial inequality in the post-civil rights era. It tends to attract progressive students who, in analyzing racial inequality, are drawn to arguments that stress structural obstacles to equality and the enduring power of white racism, especially in our criminal justice system. The course features black authors who do defend that view, but I also teach the work of others who depart from it in some measure, including heterodox thinkers like Thomas Chatterton Williams and conservatives like Jason Riley. Much like my conservative evangelical students at Cornell, my progressive students at Claremont McKenna College are less likely to assume these contrarian black thinkers are acting in bad faith or are motivated by bigotry — even when the thinkers criticize hip-hop culture or defend white police officers. So the students engage the challenging arguments and ideas instead.

As conservatives have long observed and psychologists have since confirmed, human beings are hive-minded animals whose moral judgments are shaped more by sentiments than by reason. Thus, when we are confronted by arguments we disagree with, we can easily find reasons to reject them. The search for disconfirming evidence, however, can sometimes be short-circuited, especially when we feel close to the person making an argument we disagree with. As the social psychologist Jonathan Haidt concluded in his 2012 book, “The Righteous Mind,” if we have “affection, admiration, or desire to please” other people, we lean toward them and attempt to “find the truth” in their arguments. Social proximity matters.

If we want our students to consider the work of authors they’re inclined to disagree with, we professors must take the identity of those authors into account. This doesn’t mean scrubbing all white men from our syllabuses. But when we design an education for our students, we should remember that humans are partial, tribal beings — not rational automatons.

Some readers — especially those on the right — may suspect that embracing identity in this way will only embolden campus radicals. But that objection ignores an important truth: Practicing the new identity politics in the right way can subvert the dogmas that drive its excesses. When students read books by a broad intellectual range of evangelical or female or black authors, for example, they learn that there is no single evangelical or female or black perspective. Disagreements about ideas transcend these social categories.