How ‘Diversity’ Became the Master Concept of Our Age

Diversity has come to pervade every aspect of American science and scholarship. Colleges are prioritizing hires that increase the diversity of their faculty. Applicants are asked to submit diversity statements. Diversity managers invite diversity consultants to offer diversity trainings in hope of reducing bias among an increasingly diverse faculty and student body. Prominent natural scientists refuse to speak on “manels,” that is, conference panels exclusively composed of men. Journal editors check submitted manuscripts to make sure they do not only cite white male authors; and critics demand that these gatekeepers themselves become racially more diverse to ensure a distribution of knowledge that does justice to human diversity.

The bulk of diversity practices pursue the moral-political goal of social justice by making students, faculty, administrators, and researchers more representative of the general population. However, in the context of research and higher education, diversity practices are simultaneously framed as serving epistemic goals: Knowledge produced by diverse scholars and scientists is considered superior to knowledge produced in a homogeneous group. There is now a true diversity of diversity. Diversity oriented toward social justice has been opposed to another type of diversity: viewpoint diversity. The controversy over viewpoint diversity is particularly suitable to study the specifically epistemic stakes in the valorization of diversity, because the proponents of viewpoint diversity see as their primary goal the advancement of science, not social justice.

Where did viewpoint diversity come from? In the 2010s, American social psychologists began to argue over how to deal with the fact that most of them were liberals (in the American sense) and looked at human social behavior and cognition through that ideological lens. The quarrel had been triggered by Jonathan Haidt’s argument that, for epistemological reasons, their field needed more political diversity. Only a system of ideological checks and balances would enable them to rein in the otherwise-unquestioned prejudices of the majority.

This intervention represented a challenge to the discipline’s hitherto dominant epistemic value of value neutrality because it requires the identification of researchers with a political stance. Amid the widely discussed replication crisis of psychology and other scientific fields, many of Haidt’s colleagues took seriously the concern that their moral and political biases could be part of the reason that so many of their findings could not be reproduced. The liberal-bias controversy contributed to a larger push for reforming the institutions of science to curb the inherently biased thinking of human beings.

That the proponents of viewpoint diversity focus on science does not mean that their project is free of moral-political views. In fact, their political epistemology is very much rooted in the classical liberalism of John Stuart Mill and emerged in response to the American culture wars. Part of their political mission is to emphasize scientific knowledge production rather than the reallocation of status and power among different social groups. Beginning in 2015, the nonprofit advocacy group Heterodox Academy carried the demand for more viewpoint diversity into the wider moral economy of higher education.

Before viewpoint diversity came to be fought over as an epistemic value of social psychology, social psychologists had discovered it as an object of study. This happened amid the turmoil of the American culture wars in the 1990s, which shaped the rearticulation of moral psychology as a new subfield of social psychology. Inspired by anthropology, Haidt and others began to compare moral judgments across national cultures and social classes. The primal scene of this new moral psychology was the critique of what began to look like an ethnocentric construction of morality by an earlier generation of developmental psychologists who had reduced morality to the promotion of fairness, prevention of harm, and defense of individual autonomy — a view shared by their European and North American middle-class test subjects but not by Haidt’s lower-class Brazilians, for whom morality also concerned sanctity, loyalty, and authority.

By 2001, Haidt had come to realize that the way American conservatives understood morality was more like the Brazilian poor than like American liberals. Consequently, he moved from comparing moral judgments between national cultures and social classes to comparing how ideologically dissimilar Americans thought about sexual morality at a time when gay rights had emerged as the single most divisive issue between liberals and conservatives. Haidt now sought to explain the complexity of conservative moralizing to his fellow liberals. And he argued that, if psychologists continued to confine the moral domain to concerns about fairness, harm, and autonomy, they failed to accurately explain how conservatives thought and felt about sexual mores. Among the uses of understanding diversity was more effective political messaging (which would lead Haidt to give campaign advice to Hillary Clinton’s presidential campaign against Donald Trump in 2016).

As moral psychology became a science of the culture wars, political viewpoint diversity became its principal object of study. Political-viewpoint diversity also emerged as a problem of subject position when social psychologists began to question how their own political viewpoints informed their work on the viewpoints of others. Social psychology is a human science, and it shares with the other human sciences an epistemological structure first analyzed by the French philosopher and historian Michel Foucault: Human beings are simultaneously the empirical object and the transcendental subject of social psychology. It is as people with political viewpoints that social psychologists study the political viewpoints of people. Despite Foucault’s wager, now more than half a century old, that this “strange empirico-transcendental doublet” called “man,” which constitutes both object and subject of the human sciences, would be “erased, like a face drawn in sand at the edge of the sea,” the transformation of moral psychology in the 2000s injected new urgency into the question of how to stabilize this persistent yet persistently unstable epistemological structure.

Lack of viewpoint diversity among social psychologists came to be flagged as an epistemological problem at a time when increasing political polarization and intolerance toward conflicting ideological viewpoints were identified as social problems, when distrust among conservatives in what they perceived as politically lopsided scientific knowledge grew, when diversity discourse and practices began to transform academic knowledge culture at large, and when the diversity of moral points of view had become an object of social psychological research. In 2011, at the annual meeting of the Society for Personality and Social Psychology (SPSP), Haidt warned his colleagues that social psychology, just like the other two “very liberal sciences,” sociology and anthropology, had evolved into a “tribal moral community” that actively discouraged conservatives from entering the field. “Morality binds and blinds,” Haidt argued, which might be good for a religious community but not for scientists, “who ought to value truth above group cohesion.” In his eyes, this was not only a moral issue but first and foremost a scientific problem: “We are hurting ourselves when we deprive ourselves of critics, of people who are as committed to science as we are, but who ask different questions, and make different background assumptions.”

Like many others in the science-reform movement, Haidt derived from claims about how the human mind is working another set of claims about how the human sciences should be working. He concluded his 2011 talk with a plea that SPSP become 10-percent conservative by 2020. Assuming that it was as moral and political minds that social psychologists studied the moral and political minds of others, Haidt proposed to politicize the recruitment of researchers in order to depoliticize the results of their research.

Haidt was not the first to sound the alarm in the social sciences. In the early 1990s, the political scientist Philip E. Tetlock cautioned against the growing politicization of the field. If political science merely echoed “the received wisdom of the liberal wing of the Democratic Party (or any other orthodoxy),” it would generate “few controversies and even fewer surprising discoveries that enrich our understanding of human nature and politics.” Tetlock called for a commitment to value neutrality. As a student of people’s political psychology, he was under no illusion that value neutrality was fully realizable, but he insisted that, as a regulatory ideal, it remained “a useful benchmark for assessing our research performance.”

Calling value neutrality a useful benchmark was, in fact, a bit of an understatement considering the existential importance Tetlock assigned to it. In fact, abandoning value neutrality would cost the field its collective credibility as a science: “We find ourselves in scientific hell when we discover that our powers of persuasion are limited to those who were already predisposed to agree with us (or when our claims to expertise are granted only by people who share our moral-political outlook),” Tetlock wrote. “Thoughtful outsiders cease to look upon us as scientists and see us rather as political partisans of one stripe or another.” This, however, was the early 1990s: While Tetlock decried a one-sided politicization of his field, the proposed remedy was still value neutrality — not yet viewpoint diversity.

Viewpoint diversity only entered the conversation about liberal bias in 2001, when the forensic psychologist Richard Redding made the case for sociopolitical diversity in psychology. Concerned that the American Psychological Association had expanded its advocacy efforts during the 1990s and that U.S. senators and federal judges had begun to express distrust in social scientific expertise, which they perceived as corrupted by a doctrinaire commitment to liberal values, Redding also called on his colleagues to provide analyses that are “as objective and value-neutral as humanly possible.” But, recognizing that humans could never analyze human life in a perfectly value-neutral manner, he also urged psychologists to “disclose their biases” and “foster a true sociopolitical dialogue in our research, practice, and teaching that would give equal time to opposing views.”

The disclosure of political biases in the academy was precisely what value neutrality — at least in the sociologist Max Weber’s classic formulation from 1917 — had discouraged. Redding’s creative misinterpretation turned value neutrality on its head. What set Redding and Weber apart was the advent of diversity. Redding cited the 1978 Supreme Court ruling on Regents of the University of California v. Bakke, which had declared race-based preferences constitutional if they were justified by the goal of “diversity,” as opposed to social justice. Such diversity, the late Justice Lewis F. Powell Jr. contended, brought “experiences, outlooks, and ideas that enrich the training of [students] and better equip … graduates to render with their understanding their vital service to humanity.” Piggybacking on the American Psychological Association, which in the 1990s had made cultural diversity one of the profession’s core values, Redding urged psychologists to expand their conception of diversity to include sociopolitical values, especially the hitherto marginalized values of conservatives. And thus, value neutrality had mutated, almost beyond recognition, to viewpoint diversity.

When, in the 1910s, Weber explained the meaning of value freedom in the social sciences, he explicitly advocated it as an alternative to what is today called viewpoint diversity. Value-laden science could only be justified, he argued, if “all partisan valuations will have an opportunity to assert themselves on the academic platform.” Since this was hardly the case in Wilhelmine Germany’s state-run colleges, allowing those loyal enough to the monarchist state to gain professorships to profess their moral and political persuasions turned colleges into “theological seminaries,” Weber railed, “without the religious dignity.” Weber insisted instead that no partisan valuation whatsoever should be asserted on the academic platform (while encouraging his colleagues to voice their political views in other venues such as opinion pieces in newspapers or talks in public forums).

A century later, the propagation of viewpoint diversity has taken the path not taken by Weber: It seeks to create an academy where all partisan valuations are represented. The advocates of viewpoint diversity and value neutrality share the goal of preventing the degradation of colleges into seminaries, but they seek to realize it through very different moral economies.

A decade before Haidt, Redding had already modeled viewpoint diversity on racial and gender diversity by suggesting “affirmative-action-like practices” to bring in more conservative graduate students and professors (fully recognizing the irony that most American conservatives loathed affirmative action). The resulting moral economy creates a species of scientist who defines her scientific self in ideological terms. After all, colleges can only foster viewpoint diversity through targeted recruitment if they are made aware of the viewpoints of individual faculty, students, and staff. Affirmative action for conservative social psychologists would require job applicants to present themselves as conservative social psychologists (similar to the ways in which candidates belonging to racial and ethnic minorities now signal these aspects of their identity in application letters). Whereas social psychologists committed to value neutrality just happened to be conservative or liberal and aspired to separating their political views from their scientific research, social psychologists committed to viewpoint diversity have to articulate their political standpoint as a perspective that they will carry into scientific forums such as lab meetings, peer-review processes, or conference-panel discussions where their bias will help to advance knowledge. Thereby, viewpoint diversity transforms what the historians of science Lorraine Daston and H. Otto Sibum call the “scientific persona” into a form of self-representation that hybridizes epistemic and political orientations.

Whereas value neutrality was primarily a matter of self-cultivation, of internalizing the ethos of ideological self-restraint that Weber had articulated in his 1917 lecture, “Science as a Vocation,” viewpoint diversity can only be achieved collectively. In the parlance of identity politics, speakers of American English can now say of a particular person that they “are diverse,” which means that they represent a currently underrepresented social category. Yet diversity is not a property of individuals but of groups.

In an article titled “Political Diversity Will Improve Social Psychological Science,” a politically diverse (of course) group of authors around Haidt and Tetlock argued that, individually, social psychologists suffered from confirmation bias; like all human beings, they tended to search for evidence that confirm their beliefs while downplaying disconfirming findings. “Nobody has found a way to eradicate confirmation bias in individuals,” they noted, but people had proved very apt at detecting bias in those they disagreed with. Consequently, confirmation bias could be reined in on the level of the scientific community. “We can diversify the field,” they wrote, “to the point where individual viewpoint biases begin to cancel out each other.” The proponents of viewpoint diversity, in other words, conceived of it first and foremost as a collective undertaking. In line with this collectivism, the authors of this article included “one liberal, one centrist, two libertarians, one whose politics defy a simple left/right categorization, and one neo-positivist contrarian who favors a don’t-ask-don’t-tell policy in which scholarship should be judged on its merits.”

Although Redding’s article had already made most of the points that Haidt would make again a decade later, its publication in 2001 did not initiate a controversy like the one following Haidt’s SPSP talk in 2011. Why did the liberal-bias controversy not catch on in the 1990s and 2000s but in the 2010s? Of course, one can only speculate about things that didn’t happen. One possible explanation is that the political polarization of the United States rose steadily during this period and, as skepticism toward climate research was growing more and more pronounced on the right, the politicization of science came to be recognized more widely as one of the preeminent social problems of the early 21st century. This trust problem not only concerned the external but also the internal perception of science. At the time, scientists themselves sounded the alarm that many findings could not be reproduced, especially in medicine and in social psychology. By 2015, Haidt and his colleagues presented the lack of viewpoint diversity in their field as one overlooked cause of this replication crisis.

The liberal-bias controversy represents an important chapter in the history of the so-called “post truth” era. In the 2010s, this crisis of trust in scientific knowledge gave fresh salience to the concerns that Haidt, a skillful popularizer with a wide-ranging social network, brought back on the agenda: If social psychologists wanted to produce valid truth claims about the minds of morally and politically diverse people, they would have to become more morally and politically diverse themselves.

Haidt’s provocation led to an extended, still-ongoing debate among social psychologists. The commentaries on Haidt’s plea for political diversity can be roughly sorted into two equal camps. One side considered viewpoint diversity an appropriate remedy for social psychology’s liberal bias; the other would prefer minimizing rather than pluralizing political bias in science. Many of the responses in favor of viewpoint diversity were still critical of particular aspects of the Haidtean argument. Some argued that construing viewpoint diversity exclusively in political terms was too narrow because any lack of diversity could result in systematic error. Hence, the field would also profit from religious and methodological diversity and from the inclusion of citizen scientists not confined to an academic perspective. Others agreed that increasing viewpoint diversity was desirable but cautioned that it had to be accompanied by the cultivation of tolerance because otherwise people wouldn’t feel safe to also express and take seriously divergent viewpoints.

Then there were commentators who welcomed viewpoint diversity in general but considered affirmative action for conservatives an unrealistic means to achieve it because it would be too risky for junior scholars to admit their conservative leanings. This resulted in a Catch-22: As long as liberals dominated colleges, search committees would not value conservatives as minority candidates, and as long conservatives weren’t pursued as minority candidates, liberals would continue to dominate colleges. Others argued that the overrepresentation of liberals was not simply a matter of discrimination but of self-selection based on biologically rooted personality differences between liberals and conservatives. This aspect of the human condition was not readily remediable but made it all the more important that academics became more sensitive toward the fundamental differences between liberals and conservatives without pathologizing the latter. This group of commentators valued the inclusion of nonliberal perspectives on philosophical grounds but felt pessimistic about the viability of Haidt’s activist strategy.

On the other side stood those who opposed viewpoint diversity on principle. Commentators pointed out that there was no empirical evidence that viewpoint diversity could increase the replicability of social psychological studies. Several took issue with the ethnocentric framing of those all too American pleas for a political diversity modeled on the United States’ two-party system. Others pointed out that the false generalization from the situation of American social psychology and the division of humankind into two types of people, Republicans and Democrats, could also be taken as a reason for doubling down on the need for even more diversity, especially cultural diversity.

The debate’s focus on the political landscape of the United States threw into relief some of the epistemological and political problems associated with viewpoint diversity. While Redding had introduced the idea of viewpoint diversity because he believed that the social sciences should not be missing out on the “wisdom” of any political ideology, the liberal-bias controversy of the 2010s drew attention to the fact that American conservatism had dramatically changed since the 1980s: What was excluded from social psychology and the elite academy more generally was a strain of conservatism deeply influenced by evangelical Christianity and resentment of America’s demographic changes. On the brink of the Trump Era, worried one American psychologist, the point of view that Americans called “conservative” had come to encompass attitudes better described as radical in their anti-intellectualism and willful ignorance, which were not sufficiently reasonable to join academic debate.

In the course of this debate, a group of German social psychologists declared their opposition to the affirmative-action approach to political diversity because the quest for diversity was inherently limitless and would eventually have to include even the most extreme positions: “We do not know how much diversity would be necessary to reduce these biases. Would it be enough to include liberals and conservatives? Or should communists, fascists, and even terrorists also be included?” they asked. Another German group turned the question of why social psychologists should stop at political diversity into a reductio ad absurdum by asking why advocates of viewpoint diversity did not include religious diversity and hire fundamentalists as counterweights to the biases of an otherwise atheist faculty. Wouldn’t a collaboration between evolutionary theorists and creationists cancel out their respective biases and generate a more truthful theory somewhere in the middle? Of course not. “Scientific truth,” they concluded, “is not a matter of political diversity and compromises unless one assumes a radical constructivist position.”

Politically, the problem identified by other commentators was that, even if one subscribed to such a constructivist epistemology, ideological polarization had grown so pronounced that it seemed improbable that American liberals and conservatives could actually form a community. As the philosopher Jennifer Cole Wright noted, “it’s not as if … liberal and conservative beliefs, if placed in close-enough proximity to one another, will somehow cancel (or balance) each other out.” Her colleague Bas van der Vossen recommended that “perhaps instead of undoing the profession’s homogeneity, we should strive to undo its politicization.”

Many critics of viewpoint diversity feared that the institutionalization of bias would open the moral economy of science to the political polarization of the ambient society. Haidt’s former mentor, the anthropologist Richard Shweder, joined this camp of the controversy when he argued that the “bureaucratic formalization of political and moral identities” in the form of viewpoint diversity would make things only worse. Instead, individual scholars should cultivate ideological suppleness: “Freely staying on the move between alternative points of view is still the best antidote to dogmatism.”

The moral economy of diversity that emerged from this debate not only comprised calls for quotas for conservatives and study designs less prone to researcher bias, but also the fostering of epistemic virtues as the embodiment of epistemic values. If knowledge depends on the knower, then the knower’s habitual dispositions are as important as any scientific method and professional code of conduct. Consequently, the knower becomes the target of epistemic moralizing. For instance, in the moral economy of viewpoint diversity, there is no place for dogmatists and zealots, even if their spirited commitment would be highly valued in a field that prizes activist scholars. This inevitable moralization of epistemology explains the sometimes-accusatory tone of contemporary debates over the epistemic value of diversity.

But one researcher’s epistemic virtue is another researcher’s vice. A controversy over the moral economy of science is more closely related to ethical controversies than to scientific controversies over factual claims. One important difference is that, in scientific controversies, laboratory experiments, clinical trials, or field observations will eventually lend additional weight to one of the conflicting positions. Evidence regarding psychological or genetic differences between people who today count as liberals and conservatives may or may not have bearing on how to evaluate their differences in opinion, but it certainly cannot tell researchers whether they should embrace viewpoint diversity, value neutrality, or politically more engaged forms of scholarship. These are normative questions at the intersection of ethics and epistemology.

The debate over liberal bias is ongoing, and perhaps irresolvable. It might turn out to be in the nature of ethical controversies that they cannot be settled, at least not outside of decision-making bodies that first deliberate and then rule by fiat. Whether epistemic values are irreconcilable and represent a secular analogue of the eternal struggles between the gods that Weber envisioned, or whether, as Daston and the historian Peter Galison have argued, they inform a pluralistic ethics in which researchers aspire to the practical wisdom to find the right balance between multiple epistemic virtues in response to a given scientific problem, tensions between competing orientations might persist and even fracture a discipline, as happened in anthropology in the 1980s.

At present, we can only chronicle how the ascent of viewpoint diversity is transforming the moral economy of social psychology. And we can observe how the resulting disagreements open the black box of the field’s theory of knowledge, as participants in the debate articulate and defend their otherwise-unspoken presuppositions and commitments. What this continuing controversy has already revealed is that, while the field might be politically homogeneous, epistemologically it is not.

Haidt originally framed the liberal-bias controversy as responding to an epistemological problem. But its political significance had been obvious ever since Tetlock expressed concern about nonliberal politicians and judges losing trust in what they perceived as ideologically prejudiced social scientific expertise. After all, the question of how knowledge relates to power is eminently political. As social psychologists continued to debate how to deal with their moral and political passions without SPSP or any other institutional body carrying out affirmative-action policies for conservatives, Haidt took his activism beyond the discipline. Together with Nicholas Rosenkranz, a professor of law at Georgetown University, and Chris Martin, who was a sociology doctoral candidate at the time, he founded Heterodox Academy in 2015. Martin took issue with the ideological homogenization of his own field, challenged the propagation of an activist “public sociology” by the American Sociological Association, and played devil’s advocate by confronting his colleagues-to-be with a selection of inconvenient facts that did not fit into the dominant liberal narrative spun by American sociologists. Rosenkranz was concerned that politically uniform law schools not only became intellectually lazy and produced unreflective, imprecise, and at times even erroneous scholarship, but also failed to train future lawyers who understood conservative legal perspectives well enough to craft arguments that would persuade the judges they would actually encounter — judges who happened to be significantly less liberal than law-school faculty.

Having diagnosed the lack of viewpoint diversity as a problem that not only plagued their respective disciplines but the American academy as a whole, Haidt, Rosenkranz, and Martin sought to create a forum for scholars who sought constructive disagreement beyond the ideological guardrails of their fields. What the members of Heterodox Academy did agree on was that developing a widely shared commitment to one political orientation undermined the intellectual mission of any college or discipline, if only because “he who knows only his own side of the case knows little of that.” This maxim of John Stuart Mill’s would come to define Heterodox Academy’s valorization of viewpoint diversity.

The brand of diversity advocated by Heterodox Academy emphasizes its orientation toward truth. Here, however, the pursuit of truth no longer required making the academy value-free. Instead, viewpoint diversity advocates for a meaningful representation of conflicting ideological perspectives. By meaningful, however, Heterodox Academy does not mean demographically commensurate; its goal is not social justice for groups underrepresented in higher education, like conservatives or African Americans, but the inclusion of enough divergent viewpoints to make a qualitative difference in the construction of truth claims. “We don’t give a damn about exact proportional representation,” Haidt explained in an interview. “What we care about is institutionalized disconfirmation — that is, when someone says something, other people should be out there saying, ‘Is that really true? Let me try to disprove it.’” Despite this emphasis on truth, viewpoint diversity is hardly free of political overtones. Its propagation has been a direct response to the increasing polarization of American society in the mid-2010s when colleges became one of the main battlefields for the reignited culture wars.

Heterodox Academy started out as a website with a blog and quickly morphed into an organization of more than 5,000 members who exchange thoughts in discussion forums and meet at annual conferences. Its popularity shot up when, only weeks after its establishment, student protests against alleged racism in higher education erupted across the United States. Student protesters also articulated their demands to make the college a more inclusive place in the name of diversity, but they called for racial rather than political diversity. From Haidt’s point of view, the form these altercations took — ultimatums given to college presidents, the reluctance of those presidents to argue back for fear of being perceived as blaming victims, the intimidation of faculty members who did not support the protesters — amounted to “Maoist moral bullying.” Rosenkranz likewise warned against “the increasing hostility to free speech on campus.” The opposition of Heterodox Academy to the emergence of what would soon be called “cancel culture” attracted media attention and drove up membership. The culture wars endowed a project that had grown out of a purely academic debate between social psychologists with increasing political significance.

The political philosophy underlying Heterodox Academy is primarily that of Mill’s On Liberty, excerpts of which the organization has republished with a new introduction by Haidt under the title All Minus One. Such classical liberalism required defending the right to freedom of speech, even of people one vehemently disagreed with. But it was not only this longstanding tenet of liberal thought but also the political makeup of American colleges in the early 21st century that put Heterodox Academy in the position of advocating for the conservative minority. The opposition to cancel culture had become a rallying cry of the new right and the old left. Although Haidt declared in an interview that he was “absolutely horrified by today’s Republican Party,” Heterodox Academy’s promotion of free speech on campus aligned it with the strategic interests of conservatives (even though many on the right would quickly abandon their commitment to free speech when it came to attempts to legislate curricula at public colleges in red states like Florida, Indiana, and Texas). The activism of Heterodox Academy echoed an effort by the right-wing David Horowitz Freedom Center, which in 2003 had unsuccessfully lobbied Republican members of the U.S. Congress to ratify an academic bill of rights requiring colleges to strive for greater “intellectual diversity” among faculty and in their curricula. In 2022, Florida’s Republican legislature gave an intellectual-diversity survey to the state’s public colleges to determine whether they favored liberal viewpoints and repressed divergent political perspectives. A major faculty union denounced the effort as an attempt at autocratic control and urged faculty, students, and staff not to participate. While Heterodox Academy has always presented itself as ideologically committed to the principles of classical liberalism, but not siding with any political camp and seeking to defuse the culture wars, its advocacy for viewpoint diversity inadvertently supported conservatives and libertarians as minoritized groups in American colleges. Unsurprisingly, the internet was teeming with allegations that “Heterodox Academy is purely a right-wing operation.”

While diversity is often framed as a value primarily cherished by the American left and only appropriated by other constituencies for instrumental purposes, the propagation of intellectual or viewpoint diversity by the David Horowitz Freedom Center and Heterodox Academy could also be taken to indicate that diversity has become a value shared across the political spectrum. As far as the classical liberalism espoused by Heterodox Academy is concerned, the valuation of free discussion between people of different persuasions can be traced back to Mill. But there is also an intellectual history that connects contemporary conservative and far-right ideology to the appreciation of cultural pluralism by 19th-century critics of the Enlightenment like Johann Gottfried von Herder. Present-day controversies over how to diversify academe draw from, and blend, these different traditions, bringing out the diversity of diversity.

As diversity has ascended to become the value that defines late modernity like no other, the most-pronounced tension within the moral economy of diversity is that between proponents of political and religious diversity and proponents of racial, ethnic, class, and gender diversity. In a brief sketch of 100 years of viewpoint-diversity activism on the Heterodox Academy blog, the sociologist Musa al-Gharbi diagnosed a split among viewpoint-diversity advocates into two hostile camps, one focusing on identity commitments, the other focusing on ideological commitments:

Many within the “ideological-commitments camp” seem to believe that the people in the “identity commitments” camp are the problem that has to be overcome, while many in the “identity commitments” camp describe the “ideological commitments” crowd as apologists, trojan horses, or useful idiots of white supremacists, male chauvinists, and other reactionary agendas. Consequently, neither side has made much progress in their respective goals.

While al-Gharbi believed that ultimately both camps sought viewpoint diversity and only had to work together to achieve it, others saw these competing commitments as more divergent and even incommensurable. In their plea for political diversity in social psychology, José L. Duarte and his colleagues recognized that seeking demographic diversity was valuable in its own right because it combated effects of past and present discrimination, increased tolerance, and created faculty bodies that would be more appealing to students from diverse demographic backgrounds. But its effect on improving the validity of science was indirect at best: “Viewpoint diversity may therefore be more valuable than demographic diversity if social psychology’s core goal is to produce broadly valid and generalizable conclusions. (Of course, demographic diversity can bring viewpoint diversity, but if it is viewpoint diversity that is wanted, then it may be more effective to pursue it directly.)”

The meteoric rise of the value of diversity is transforming the moral economy of science and scholarship. Viewpoint diversity came to serve as the legal justification of affirmative action in student admissions, even though critical observers doubted that the diversity policies characteristic of American progressive institutions are primarily motivated by a valuation of perspectival pluralism. Considering recent right-wing efforts to censor the discussion of critical race theory and LGBT literature in schools and colleges, one might also question whether viewpoint diversity is what motivates conservative efforts like the Florida viewpoint-diversity survey in 2022. However, what adapting diversity to different ends shows is that, despite deep hostility between the culture-war parties, they all consider the value of diversity self-evident enough to package their political projects in diversity discourse.

In the emergence of this expansive apparatus, the controversy over viewpoint diversity among social psychologists might appear as a rather-marginal event. Yet it unpacks what is at issue in the valorization of perspectival diversity as the very value that all sides profess. Maybe it is because of social psychology’s longstanding commitment to value neutrality that its actors have engaged in a serious epistemological and methodological debate over the challenge that viewpoint diversity poses to their knowledge culture. By opening the normative black box of their scientific practice, these researchers rendered visible to themselves and outside observers the stakes in the current restructuring of the moral economy of science. In the process, perspectival diversity has lost its self-evidence. One conclusion to be drawn is that disciplines other than social psychology would equally profit from open debate over the place of diversity in their respective conceptions of good scholarship. And, given that not all disciplines have traditionally valued value neutrality the way social psychologists did — I am thinking of my own fields, cultural anthropology and science studies — debates in other disciplines might take very different courses.

A second conclusion is that the discourses and practices surrounding diversity have been shaped in the image of American society. Nevertheless, they are now widely adopted in other Western societies and by multinational corporations that also operate outside of North America, Europe, and Australia. This is striking, given how closely the growing valuation of diversity has been coupled to the contingencies of a 1978 U.S. Supreme Court decision. The more recent controversy over viewpoint diversity in social psychology and the creation of Heterodox Academy also only make sense against the backdrop of America’s reignited culture wars. In 2011, a group of researchers from a Swiss French business school reviewed the scientific literature on diversity and found that 90 percent of the authors were American, Canadian, Australian, or British — and rarely cited non-Anglophone literature from Germany, France, or China. But the values, assumptions, and approaches of the English-speaking world were not necessarily appropriate for European business environments or in other parts of the world. European countries did not share the American emphasis on racial differences, which, the researchers worried, fostered rather than contained racism, and collectivist cultures disapproved of the celebration of differences associated with diversity. “One of the important reasons why diversity research is unhelpful to diversity practice,” Karsten Jonsen et al. argued, “is that it itself is not diverse, especially with respect to its cultural assumptions.” In their eyes, the U.S.-centric diversity literature was symptomatic of “intellectual imperialism.”

One does not need to share the polemical impulse of these authors against the ethnocentrism of diversity discourse to recognize the epistemological and political paradox at the heart of diversity, which pertains not only to the business world but also to higher education: An ideal diversity would need to be inclusive of the many forms that nondiversity and even anti-diversity can take. In reality, however, diversity is always selective and advances the viewpoints and interests of some groups at the expense of the viewpoints and interests of others. A “view from everywhere,” as Lorraine Daston called it in a talk on objectivity in the humanities, is no more realizable than a view from nowhere; both are at best regulative ideals.

In 2023, the Supreme Court’s conservative majority reconsidered and revised the diversity justification of race-conscious admissions programs, which, some four decades ago, made educational diversity a central concern of American higher education. It is still too early to tell what abolishing the legal incentive for educational diversity will mean for the moral economy of science. Will colleges decouple the morally motivated pursuit of social justice from the epistemologically motivated pursuit of perspectival pluralism? Or has diversity become so entrenched in American colleges that they will continue its promotion, even though it has ceased to make their social-justice goals legally defensible? While these are questions for future historians of science, what those of us who participate in the moral economy of diversity need to discuss today is if, how, and why we valorize diversity as an epistemic value, how to relate it to other epistemic and nonepistemic values, and what role it is to play in the quickly changing political situation in which we find ourselves. Social psychologists have provided a template. Now the floor is open to the rest of us.

This essay is adapted from “The Moral Economy of Diversity,” first published in History of the Human Sciences.