Introduction When Difference Makes A Difference

Taking seriously the social dimensions of knowledge puts pressure on the assumption that epistemic agents can usefully be thought of as autonomous, interchangeable individuals, capable, insofar as they are rational and objective, of transcending the specificities of personal history, experience, and context. If this idealization is abandoned as the point of departure for epistemic inquiry, then differences among situated knowers come sharply into focus. These include differences in cognitive capacity, experience, and expertise; in access to information and the heuristics that make it intelligible; and in motivating interests and orienting standpoint. Dissent takes on rather different significance, as a potentially productive feature of epistemic life rather than evidence of a failure of aperspectivality or an indication of error. The central questions are, then, what forms of diversity are epistemically consequential, and how can they best be deployed to ensure that the beliefs we warrant as knowledge are as well grounded and truth-tracking as possible.

Many of those who treat diversity and dissent as epistemic resources rather than impediments take the view that well functioning epistemic communities embody democratic ideals of public deliberation.¹ The rationale for this is derived, in broad outline, from the liberalism of John Stuart Mill (1869), sometimes by way of Mertonian sociology (Merton 1942). The central principle is that the more robust a community's mechanisms for bringing diverse perspectives to bear on epistemic questions of public import, the more effective it is in generating and ensuring responsiveness to all the information and insights held by its members. This presupposes two key conditions: that there be salient epistemic diversity among participants, and that social conditions allow for the effective mobilization of dissent and response to it.

This is plausible enough as an abstract ideal, but much remains to be done to specify how, why, and under what conditions active dissent and deliberative processes conduce to epistemic success. This is the challenge taken up by contributors to this special issue on epistemic diversity and dissent.

Elizabeth Anderson opens the issue with an account of the epistemic powers of democratic institutions that provides a useful framework for assessing the models of public deliberation proposed by social epistemologists and philosophers of science. She advocates a Deweyan experimentalist model on the grounds that it integrates the epistemic powers of three distinctive features of democracy: (1) norms of inclusiveness that recognize the value of diversity in experience and perspective, (2) mechanisms for pooling these epistemic resources, and (3) mechanisms for ensuring dynamic responsiveness to outcomes. The epistemic implications of these criteria are illustrated by a study of natural resource management by community forestry groups in India and Nepal. There was much to be gained by the community as a whole when strategies were found to ensure that women—who were the primary users of forest products but had largely been excluded from group decision-making—could bring their situated knowledge to bear on collective decisions.

Anderson's case for recognizing the epistemic value of democratic institutions clarifies the reasons why epistemic diversity and the dissent it produces are, as Miriam Solomon puts it, "widely approved by social epistemologists." But it also sharpens the questions with which I began: Are there particular kinds of epistemic diversity that such institutions should be designed to incorporate? Is dissent an unqualifiedly good thing epistemically? Are processes of public deliberation the best method for pooling epistemic resources?

These questions are especially pointed in the case of scientific inquiry, given the weight of historical and philosophical studies of science which demonstrate that most sciences, most of the time, advance through the practice of "normal science"—a state in which, as Kuhn (1962) famously described it, diversity and disagreement are sharply circumscribed. Here democratic ideals come up against the constraints of focused, disciplinary practice; the effective coordination of research effort requires practitioners to work within a framework of shared theoretical commitments and consensus about the goals and standards of practice.

Solomon considers the case of a novel theory of smell that illustrates many common mechanisms by which practitioners invested in an entrenched paradigm deflect dissent. Professional reward systems, disciplinary cultures, and the interplay of strong personalities all seem to conspire to ensure that, despite empirical successes and theoretical promise, Luca Turin's "vibrationist" theory has received little uptake in the scientific community. Solomon makes it clear that she doubts whether deliberative processes can counteract such canalization of scientific thought. Indeed, she sees these as part of the problem rather than the solution, inasmuch as they are vulnerable to group dynamics that generate "groupthink", not only suppressing dissent but amplifying error and bias. This might suggest that Solomon would favor strongly normative policies designed to increase diversity among scientists and ensure a hearing for dissenting views. But despite rejecting "laissez faire" approaches, Solomon does not endorse normative policies that target particular forms of diversity of the kind Anderson describes or that others recommend to counteract sexist and androcentric bias in the sciences. Presumably such policies are warranted only in cases where the suppression of diversity is systematic, but in the case Solomon considers, a bewildering array of factors play a role. "Diversity is a blunt instrument," she argues; rather than attempt to specify, in advance, which forms of cognitive diversity will make a positive difference, she recommends a framework for the equitable balancing of decision vectors (cf. Solomon 2001, 2006).

The worry that the sciences not only allow for but often depend upon group dynamics that suppress dissent is also a central concern for Deborah Tollefsen and John Beatty. Tollefsen urges that we attend to the specifics of scientific teamwork, rather than endorse idealized models of rational deliberation as an appropriate standard for scientific practice (as Longino has done), or reject them as untenable and possibly counterproductive (as Solomon does). She offers an account of the conditions for effective joint agency that enables her to distinguish the forms of dissent that can be tolerated within cooperative groups and those that undermine their capacity for teamwork, depending on the nature and degree of their internal cohesiveness. This also allows her to suggest a number of strategies for counteracting the more pernicious effects of groupthink, ensuring that internal dissent and external critiques will get a hearing even when effective joint action requires a high degree of intra-team consensus on goals and working assumptions.

Beatty, in an especially striking and consequential case study, considers a range of factors that do not dampen internal disagreement so much as mask it in the public stance taken by scientific experts. He examines the deliberations of an elite panel of cold war era scientists charged with the task of determining maximum acceptable levels of radiation exposure. Despite widely varying estimates, they arrived at "joint acceptance" of a final report that presented a unified response to the questions they were charged with adjudicating. This came at the expense of considerable simplification, however; the joint report obscures the fact of internal disagreement and withholds crucial information about areas of uncertainty that underlay this dissent. Although the experts involved disagreed on scientific matters, they shared a commitment to reinforce the credibility and social relevance of science at a time when public ambivalence—especially about nuclear science and genetics—was particularly acute. As Beatty notes, this account concurs with many social histories of science that detail the paternalistic impulses of scientific experts and the mechanisms by which they recruit and manipulate political capital to maintain the status of their fields. But the scientists in this case were also concerned with accountability to the lay public, and were committed to ensuring that political interests should not displace scientific considerations in deciding urgent policy issues. In short, the reasons why dissent may be suppressed in science can be much more complex than those typically acknowledged by philosophical models of deliberation. They include an outward-looking concern for the public ramifications of scientific consensus as well as the internal dynamics that secure enough common ground to make effective teamwork possible.

On the other side of the divide between expert and lay public, David Coady considers the question of whether novices should take into account the number of people who subscribe to the position of one expert rather than another when disagreement among experts is manifest. He makes the case for qualifying Goldman's (2001) brief against "going by the numbers," because of possible non-independence among an expert's followers. Rarely, argues Coady, are conditions of non-independence realized to such a degree that novices are justified in automatically discounting the judgments of followers. When non-experts have little else to go on, it is reasonable to give weight to the opinions of followers unless they have grounds for believing that these particular followers are unreliable judges of the experts they follow. The selection pressures that operate in the propagation of rumors suggest why this is the case; transmitters judge the plausibility of the rumors they pass on. Research on information cascades illustrates the advantages that are gained when non-experts give weight to what other non-experts believe. Coady's analysis brings into focus the importance of nuanced, second order appraisals of epistemic agency that take into account the social contexts and motivations, as well as the cognitive capacities, of knowers whose opinions might otherwise be discounted.

The question of how best to deploy the resources of epistemically diverse communities presupposes an underlying set of questions about nature of the differences that can arise between epistemic agents. Rebecca Kukla addresses this issue directly, arguing that experientially shaped differences in perceptual acuity and inferential capacities put some epistemic agents in a position to know certain things better than others do in a particularly strong sense; they may be entitled to warrant knowledge claims on grounds that are not accessible to others. She posits an epistemic counterpart to the contingent, cultivated capacities for moral perception associated with Aristotle's account of "second natures." Given an inferentially rich account of perception, we should expect to find that our capacities to "see" and to adjudicate the evidential import of what we see are significantly shaped by contingent histories of experience and habituation. This argument for epistemic diversity calls into question the conventional requirement that our reasons for epistemic judgment must be transparent—democratically accessible to all—if they are to count as objective and rational. Kukla maintains that, while epistemic practice must be held accountable to an independent reality, it need not be aligned with epistemic ideals of aperspectival warrant. Epistemic agents whose perceptual plasticity has been tuned in distinctive ways should be accounted more objective than others whose second natures are comparatively less refined, at least in the domains to which their special acuity is relevant. Indeed, Kukla argues, perspectival differences represent an important epistemic resource that diverse communities will only effectively deploy if their members cultivate a capacity to appraise the differences that second nature tuning can make in our strengths and weaknesses as epistemic agents.

For present purposes Kukla sets aside the question of how these second nature epistemic capacities are distributed: whether distinct social groups develop characteristic forms of acuity, and whether, more specifically, those disadvantaged by systems of structural inequality may not have specific forms of epistemic advantage as a consequence of their distinctive experience of social inequality.² Miranda Fricker, Nancy Daukas, and Kristina Rolin take up just this issue. They consider the ramifying epistemic effects of social institutions and patterns of interaction that fail to meet Anderson's criteria for democractic inclusiveness and responsiveness.

Fricker describes a form of epistemic inequality that can arise when the linguistic or conceptual resources for representing social experience embody norms that reflect the experience and expectations of those who occupy positions of comparative privilege. Those who are socially marginal on any of a number of dimensions may find that significant aspects of their experience are incommunicable or, indeed, unintelligible (to themselves and to others), where it diverges from these dominant norms. She considers, for example, the difficulties women encountered in articulating their experience of sexual harassment when concepts that capture its impact on their lives were not widely available, and the dissonance caused by homophobic stereotypes in contexts where there are few resources for representing homoerotic attraction in positive terms. If these difficulties in rendering experience communicatively intelligible are systematic and asymmetrical—if they track patterns of social inequality rather than arising idiosyncratically—then they constitute the central form of "hermeneutical injustice." Fricker argues that such injustice not only harms those so disadvantaged, but also constitutes a "collective disablement." Key forms of experience, and the understanding of self and of society based upon them, are rendered inaccessible to collective understanding. This perpetuates hermeneutical lacunae that are both the consequence of and a contributing factor to structural forms of social inequity. Dissent is thus suppressed in an especially consequential way; dissonant views cannot get a hearing, not just because their bearers do not have access to public venues, but because even when they do, they will not be comprehended.

Although Fricker does not press this aspect of her analysis, outsiders to a dominant culture or those who occupy subordinate social positions within it are often critically aware of the partiality of norms of action that are taken for granted and projected as universals in the dominant culture. In the process, they may develop an acuity of perception, an alertness to the dynamics of power, that is not cultivated by those in positions of privilege. This is a form of perceptual tuning that has been widely remarked by critical race theorists and by feminist scholars, among others, and is the basis for the thesis of epistemic privilege associated with various forms of standpoint theory. Daukas uses a hypothetical case to illustrate the distinctive powers of discernment that may be developed by those who directly experience subtle forms of race and gender bias; as Kukla's analysis suggests, the perceptual grounds for their adjudication of claims about such bias may be largely inaccessible to those who lack such experience. In a similar vein, Rolin considers the substantial shift in recent decades in our understanding gender inequity in the sciences—away from an explanatory framework in which only overt discrimination or self-selection could account for the persistently marginal status of women, to a growing appreciation of "subtle" forms of marginalization (MIT 1999, Sonnert and Holton 1995). Rolin argues that the "socially grounded perspectives" of women who work in such institutions have played a key role in bringing these mechanisms to light, challenging assumptions that could be treated as "default entitlements" three decades ago, when Cole wrote Fair Science (1979). These perspectives brought into play a broader range of evidence and helped to establish a conceptual framework for understanding gender inequality predicated on more plausible models of agency and interaction patterns.

Daukas wrestles with the problem of how we might best counteract the effects of "unjust epistemic exclusion." She argues that effective epistemic inclusiveness will require the inculcation of what she describes as "epistemic trustworthiness." We are only likely to grasp the insights afforded by experience that diverges from our own if we cultivate a sophisticated second order capacity for appraising the domain-specific strengths and weaknesses of epistemic character that arise from particular histories of perceptual habituation. This requires that we develop strategies for counteracting the dispositions that incline us to marginalize dissident experience. Daukas (following Narayan 1988) urges a stance of "methodological humility," informed by an appreciation that those in disprivileged social positions may have experience that affords them epistemic advantage in understanding the forms and effects of inequality. Rolin's example illustrates how collective understanding can be enhanced when public discourse shifts so that experience that was previously largely inscrutable becomes communicatively intelligible and gets uptake as authoritative. Her primary concern is to show why such a shift in intelligibility does not entail a corrosive relativism. To do this she counters the presuppositions that generate the "bias paradox" according to which any attribution of epistemic privilege to a "socially grounded perspective" must either collapse into foundationalism or undercut its own claims to epistemic authority. A more promising approach, she argues, is afforded by a contextualist theory of epistemic justification; contextualism has the resources to explain how claims to epistemic privilege can be warranted when a broader shift in context calls into question the credibility of assumptions formerly accepted as entitlements.

Taken together, the signal contribution of the essays that comprise this special issue is to complicate our operative conceptions of epistemic agency and deliberative process. They expand the scope of what "the social" encompasses in social epistemology, drawing attention to forms of epistemic diversity that track power and to institutional conditions that have the capacity to systemically suppress dissent. The resources necessary to adequately address these social dimensions of knowledge lie not only in refined models of deliberative process but also in the kinds of empirical research that illuminate the group dynamics, patterns of social inequality, and institutional conditions that generate epistemic diversity and structure its reception.