Diversity Is a Principle, Not A Trend

The Diversity Principle by David B. Oppenheimer

Announcement

Yale University

During a time when the word “diversity” has been tossed around as a political talking point, Berkeley Law Professor David B. Oppenheimer is doing something necessary: he is insisting that we dig deep into history.

In The Diversity Principle: The Story of a Transformative Idea, Oppenheimer traces a 200-year intellectual lineage behind an idea that many Americans do not fully understand. His argument is simple yet radical – he believes and demonstrates that diversity is a foundational principle of modern education, democratic life, and institutional excellence.

Oppenheimer has spent much of his career exploring equality law, discrimination, and institutional decision-making. The New Yorker once called him America’s “diversity detective,” a description that fits his newest book well. He moves carefully across time and geography, showing how what we now call the “diversity principle” emerged from Euporean educational reform, took shape in struggles for academic freedom, and was refined through civil rights, women’s rights, and disability rights movements.

One of the most striking interventions in the book is historial. From Oppenheimer’s perspective, diversity did not begin as a corrective to discrimination. It began as a theory of knowledge. He shared with me, “I think the most overlooked parts of the lineage are (1) the principle’s deep roots in the founding of the modern research university, (2) the connection to academic freedom, and (3) the important role of the voices of women.” He added, “Diversity is widely seen as a twentieth-century invention, created to justify affirmative action. But it was a founding principle of the Humboldt model of higher education, the nineteenth-century model that describes nearly every top research university today.”

Wilhelm von Humboldt’s vision of the university rested on the idea that knowledge advances through the clash and exchange of ideas. However, that exchange depends on who is allowed in the room. Oppenheimer explained that Humboldt understood that “for diverse ideas to flourish and for people with diverse backgrounds to conduct research free of political influence, universities had to be protected by academic freedom.”

The link between diversity and academic freedom runs through The Diversity Principle, giving it particular urgency. Oppenheimer shows that 19th-century campaigns to open the University of Berlin to Catholics and Jews, and Oxford and Cambridge to non-Anglicans, were not primarily framed as moral obligations. They were framed as intellectual necessities, as excluding entire groups distorts knowledge itself.

The story continues into the 20th Century, where diversity helped shape arguments for freedom of speech, academic freedom, and equal protection. The principle mattered not only in universities but in courts, workplaces, and democratic movements. Today, Oppenheimer argues, it is reinforced by decades of empirical research across education, organizational theory, business, and the social sciences.

Yet public debate often ignores this history. Instead, diversity is treated as cosmetic or ideological, detached from learning and institutional performance. Oppenheimer is especially clear about one persistent misunderstanding. He shared, “I think the most misunderstood part of the principle is that causal connection between experiential or identity diversity and viewpoint diversity. This is where those who support viewpoint diversity while disparaging the value of identity diversity miss the point.”

He cites John Stuart Mill’s 1867 address to students at St. Andrews, where Mill argued that engaging with people from different nations, religions, and social positions is essential to education itself. Oppenheimer noted, “That’s equally true today.” The idea that viewpoints float free of experience, he suggested, has never been historically or empirically supported.

The book arrives as universities grapple with the Supreme Court’s recent admissions decisions and mounting political pressure. Here, Oppenheimer urges readers to distinguish between what the Court actually held and what many institutions fear it held.

He stated, “When you put aside the dicta, all the Court did was hold that universities could not consider an applicant’s race as a factor in making admissions decisions. Universities can still recruit students of color and others who will contribute to their diversity, to ensure a broadly diverse pool of applicants from whom to choose.”

He explained what remains legally permissible: considering students who grew up in disadvantaged neighborhoods, attended under-resourced schools, are first-generation, speak languages other than English, or overcame racist treatment and lowered expectations. He also suggests that universities can partner with K-12 schools and improve campus climate and retention.

However, Oppenheimer shared with me: “The question is, will they?” He added, “Will they lead, or go along? Will they see this as a test of what they know empirically, that diversity improves learning, or will they do what’s easy, at the expense of the education they provide their students?”

That question is central in the book. Repeatedly, Oppenheimer distinguishes between diversity as an intellectual practice and diversity as an aesthetic. Institutions, he argues, must be judged by outcomes, and not slogans.

He explained, “We have to look behind the curtain. Institutions should publish their commitment to diversity (and to non-discrimination and inclusion), but they should also be transparent about what they’re actually doing, and how well it’s working.”

Oppenheimer also engaged Justice Clarence Thomas’s critique that diversity serves as an elite preference for visual difference rather than structural change. He stated, “Justice Clarence Thomas (of whom I’m a sometimes unlikely admirer) complains that diversity is simply an aesthetic preference by liberals to see some dark faces in otherwise white spaces. Sometimes that’s true, but institutions that work to be inclusive move beyond the aesthetics and gain the empirically tested benefits of diversity, including gender, race, ethnic, and viewpoint diversity.”

What makes The Diversity Principle especially valuable is its global scope. Oppenheimer situates U.S. debates within a wider international tradition, linking German and British academic freedom movements to the anti-apartheid struggle in South Africa. These histories, he argues, matter precisely because political pressure is not a new phenomenon. He shared with me, “When we acknowledge that our understanding of the value of diversity is linked to the movement for academic freedom in Germany and England, and to the anti-apartheid movement in South Africa, we strengthen the argument in favor of valuing diversity and academic freedom in the U.S.”

The book also recovers voices that are often pushed to the sidelines in intellectual histories. For example, the perspectives of Caroline von Humboldt, Harriet Taylor Mill, and Pauli Murray. These women’s contributions remind readers that diversity has never been driven by a single constituency or moment. It has always been shaped by those pushed to the margins of institutions.

At its core, The Diversity Principle asks universities, courts, and organizations to stop pretending that diversity is optional. Oppenheimer makes it clear that diversity is not a favor granted to the excluded. Instead, it is a condition for excellence, discovery, and democratic legitimacy.

In a time when many institutions are choosing silence or retreat, Oppenheimer’s work insists on something else – memory. The reminder that, properly understood, diversity is a commitment to knowledge itself.