Epistemology is social in a number of ways, and it has been so for a long time, at least since Plato.1 In recent years, the social aspects of epistemology have been the subject of increasing (and increasingly sophisticated) philosophical attention. Social epistemology is a blooming discipline, full of exciting work on topics old and new. This book brings some central parts of this work together in one place, making them accessible to students and researchers alike. We have collected work under five headings: conceptions of social epistemology, trust in testimony and experts, reasonable peer disagreement, judgment aggregation, and social-system design.
Part I represents three approaches to social epistemology. In chapter 1, Alvin Goldman provides an overview of social epistemology that divides it into three categories. The first category, “individual doxastic agent social epistemology,” concerns individual belief-forming agents and how they should respond to social sources of evidence, such as evidence from the testimony of others. The second category, “collective doxastic agent social epistemology,” concerns collective belief-forming agents, such as juries and committees, which are themselves constituted by other agents. How should these collective agents go about forming their beliefs? The third category, “systems-oriented social epistemology,” concerns entire social systems such as legal adjudication systems and systems of peer review for academic research. Systems-oriented social epistemology evaluates these systems epistemically in terms of how they influence their members’ beliefs. This tripartite classification of social epistemology is reflected in the structure of the current volume (beginning with part II). Individual social epistemology is represented by parts II and III, collective social epistemology by part IV, and systems-oriented social epistemology by part V. Thus, chapter 1 serves as an organizing piece for (most of) the volume as a whole.2
In chapter 2, Paul Boghossian considers the problem of epistemic relativism as it arises in social systems. Different communities seem to have different “epistemic systems”—that is, different systems of rules or principles about the conditions under which belief is justified. One system of rules may imply that perceptual evidence outweighs evidence from religious texts when the two conflict; another system may imply the opposite. What could make one such system better or more correct than another? One might answer: nothing. Developing that answer, each epistemic system might be considered right on its own terms, with no system being objectively superior to any other. Although Boghossian does not endorse this relativist view, he formulates, motivates, and explores it in a charitable spirit. In chapter 3, Miranda Fricker lays out a different approach to social epistemology, one that gives the field a particularly tight connection to political philosophy. Following Edward Craig, she stresses our need to find “good informants,” people who will tell us the truth.3 Various societal norms of credibility can be viewed as arising to fulfill this need. However, these norms often distribute credibility unjustly, assigning it only to the powerful. By focusing on this kind of epistemic injustice, Fricker adds a new political dimension to the field; and she does so from a classical truth-centered starting point.
Part II focuses on the branch of social epistemology most widely discussed in recent years, namely, the epistemology of testimony. Under what conditions are testimony-based beliefs justified? Must a hearer first confirm the reliability of informants before taking them at their word? Or is she justified in trusting them right away, without first checking up on them? When testimony-based beliefs are justified, what is it that makes them justified? Is it simply a matter of the hearer’s evidence for the reliability of the informant, or is something else involved—something like one’s interpersonal relationship with an informant, or even the mere fact that he invites one to trust him? Jennifer Lackey explores these and related issues in chapter 4. She gives an opinionated overview of this terrain, ultimately arguing for her own hybrid position. In chapter 5, Sanford Goldberg pushes beyond the question of when and why one is justified in believing what other people assert. He takes up the related question of when and why one is justified in disbelieving what other people don’t assert. Consider, for example, the proposition that Mars was destroyed by a comet last week. If this proposition were true, someone or some media channel would have asserted it by now in a prominent place; and so, plausibly, one is justified in disbelieving it. Goldberg inquires into the general conditions under which one can obtain this kind of justification for disbelieving, and then goes on to explore some theoretical upshots of the results. In chapter 6, Alvin Goldman inquires into how novices should decide what to believe on a given topic when experts on that topic disagree. Given that they are novices, how can they tell which experts are the most trustworthy? Goldman explores several attempts to resolve this conundrum, for example, by having the novice inquire into the past track records of the experts she knows to disagree, or by having her zero in on a majority expert opinion by consulting a number of additional experts. Goldman delineates these proposals and several others and weighs the relative merits of all of them.
Part III presents the problem of disagreement among peers. Let’s say that your “peers” (on a given topic) are those people who are your equals in terms of reasoning ability, exposure to relevant evidence, and reasoning effort heretofore invested. Suppose you are in the presence of someone you know to be a peer on a topic such as whether God exists or whether the next president will be a Republican. What should you do on learning that you and your peer have conflicting beliefs? Should you adopt your peer’s belief, stick with your own, split the difference by assigning equal credence to both options, or what? In certain domains such as the religious and the political, it is sometimes said that the proper response to peer disagreement is to recognize that “reasonable people can disagree” and leave it at that. But can peers (as defined) really be reasonable when they disagree? In chapter 7, Richard Feldman argues to the contrary: since peers share the same evidence, and a given batch of evidence justifies exactly one doxastic attitude (belief, disbelief, or agnosticism) toward a proposition, peers cannot reasonably disagree.
In chapter 8, Adam Elga addresses many of the same issues within a framework that evaluates degrees of belief. He develops a version of the position that when you believe someone to be your peer, you should give her view the same weight you give your own. He defends this position from a number of objections and extends its scope to include cases in which disputing parties do not take themselves to be peers. In chapter 9, Thomas Kelly argues that Elga’s “equal weight view” gives too much probative force to peer opinion. In place of the equal weight view, Kelly develops what he calls the “total evidence view,” according to which peer opinion has some probative force but less than the equal weight view assigns it.
These essays on peer disagreement theorize about what individuals should believe in various social scenarios. A different sort of social epistemology theorizes not about what individual agents should believe but (in line with Goldman’s “collective doxastic agent social epistemology”) about what group agents should believe. Part IV concerns this issue: what a group should believe, as opposed to what individuals should believe. In chapter 10, Christian List explores the issue from a formal point of view. He begins by introducing the theory of “judgment aggregation,” the theory of how group judgments should be made on the basis of the judgments of the individuals who compose a group. After introducing some striking difficulties and impossibility results for commonsensical “majority vote” proposals, he launches into an analysis of several interesting judgment aggregation methods with respect to two epistemic desiderata: rationality and knowledge. On both of these desiderata, different methods perform differently in different circumstances. Nonetheless, there are some informative results that bear on which judgment aggregation methods best promote group rationality and knowledge—or so List argues. Now you might doubt that groups themselves can make judgments at all, let alone rational judgments or judgments amounting to knowledge. In chapter 11, Philip Pettit rejects these doubts. Since certain kinds of groups can implement rational judgment aggregation methods, Pettit claims, these groups can have a kind of rational unity that is sufficient for making judgments and indeed sufficient for these groups to have minds of their own. These groups can even be, in an important sense, persons.
Finally, part V focuses on social structures such as legal systems and, in line with Goldman’s “systems-oriented social epistemology,” evaluates these systems epistemically in terms of how they influence the beliefs of their members. In chapter 12, Larry Laudan explores the epistemology of the contemporary American criminal trial system. He starts by identifying a number of epistemologically significant aspects of that system. Then he argues that current rules about the admissibility of evidence are epistemically suboptimal, leading to numerous errors that could be avoided via the adoption of different rules. In chapter 13, Don Fallis explores one of the largest contemporary instances of mass collaboration for epistemic purposes: Wikipedia. He compares Wikipedia to traditional encyclopedias such as Britannica and to other information sources, judging them all along a number of epistemic dimensions such as reliability and fecundity. His assessment is balanced but largely positive and in favor of Wikipedia over more traditional encyclopedic information sources. In chapter 14, Cass Sunstein explores two systems through which people can form their beliefs on the basis of interactions within groups: deliberation and prediction markets. Deliberation is the familiar process of group discussion. Prediction markets facilitate widespread betting on the truth of a given proposition, and people use the bets to estimate the probability that the proposition is true. These markets have been remarkably successful, indeed so successful that Sunstein argues that they should often be used instead of deliberation. In chapter 15 (the final chapter), Kevin Zollman explores the extent to which scientists should share their results with one another. He argues via computer simulations of alternative procedures that in an important class of cases it is best to restrict information sharing. His main idea is that when everyone shares information with everyone else, misleading initial research results can polarize the community on mistaken views, and such polarization can be avoided through information restriction. He thus connects social epistemology quite closely with philosophy of science.
Zollman is not the only author here to connect his work to other fields. Laudan and Goldman (in both of his essays) also relate their themes to the philosophy of science. Pettit makes similar connections to metaphysics and the philosophy of mind; Fricker to feminist philosophy and political philosophy; Feldman to the philosophy of religion; and so forth. These connections provide an inflow and outflow of ideas that bring new insights to all the branches of study involved. Social epistemology is a richly linked node in the network of contemporary thought. Yet it is still a branch of epistemology. All the work in this book takes central epistemological topics such as the pursuit of truth as its starting point. From this starting point new routes are charted. Unseen problems get seen, unrecognized alliances get recognized, and unmade proposals get made; theoretical progress ensues. This book brings some of that progress together, in the hope that it will generate more of the same.
Notes
Thanks to Alvin Goldman for helpful comments on multiple drafts of this introduction.
1 Plato’s Republic theorizes about the division of cognitive labor, and his Charmides addresses the epistemology of expert testimony. On the topic of trust in experts, see chapter 6. On the problem of division of cognitive labor, see Philip Kitcher, The Advancement of Science (Oxford: Oxford University Press, 1993), chap. 8. For a journal issue devoted to the history of social epistemology, see Episteme 7, no. 1 (February 2010).
2 For Goldman’s extended work in systems–oriented social epistemology, see his Knowledge in a Social World (Oxford: Oxford University Press, 1999).
3 See Edward Craig, Knowledge and the State of Nature: An Essay in Conceptual Synthesis. (Oxford: Oxford University Press, 1990).