Online research in philosophy

David Hume advances a reductionist epistemology of testimony: testimonial beliefs are justified on the basis of beliefs formed from other sources. This reduction, however, has been misunderstood. Testimonial beliefs are not justified in a manner identical to ordinary empirical beliefs; it is true, they are justified by observation of the conjunction between testimony and its truth, it is the nature of the conjunctions that has been misunderstood. The observation of these conjunctions provides us with our knowledge of human nature and it is this knowledge which justifies our testimonial beliefs. Hume gives a naturalistic rather than sceptical account of testimony.

I present an account of what it is to trust a speaker, and argue that the account can explain the common intuitions which structure the debate about the transmission view of testimony. According to the suggested account, to trust a speaker is to grant her epistemic authority on the asserted proposition, and hence to see her opinion as issuing a second order, preemptive reason for believing the proposition. The account explains the intuitive appeal of the basic principle associated with the transmission view of testimony: the principle according to which, a listener can normally obtain testimonial knowledge that p by believing a speaker who testifies that p only if the speaker knows that p. It also explains a common response to counterexamples to this principle: that these counterexamples do not involve normal cases of testimonial knowledge.

The assumption that we largely lack reasons for accepting testimony has dominated its epistemology. Given the further assumption that whatever reasons we do have are insufficient to justify our testimonial beliefs, many conclude that any account of testimonial knowledge must allow credulity to be justified. In this paper I argue that both of these assumptions are false. Our responses to testimony are guided by our background beliefs as to the testimony as a type, the testimonial situation, the testifier''s character and the truth of the proposition testified to. These beliefs provide reasons for our responses. Thus, we usually do have reasons, in the sense of propositions believed, for accepting testimony and these reasons can provide evidence for the testimonial beliefs we form.

Is it legitimate to acquire one’s moral beliefs on the testimony of others? The pessimist about moral testimony says not. But what is the source of the difficulty? Here pessimists have a choice. On the Unavailability view, moral testimony never makes knowledge available to the recipient. On Unusability accounts, although moral testimony can make knowledge available, some further norm renders it illegitimate to make use of the knowledge thus offered. I suggest that Unusability accounts provide the strongest form of pessimist view. I consider and reject five Unavailability accounts. I then argue that any such view will fail. But what is the norm rendering moral testimonial knowledge unusable? I suggest it lies in the requirement that we grasp for ourselves the moral reasons behind a moral view. This demand is one testimony cannot meet, and that claim holds whatever account we offer of the epistemology of testimony. However, while appeal to this requirement forms the most plausible pessimist view, it is another question whether pessimism is correct.

Testimony is responsible, either directly or indirectly, for much of what we know, not only about the world around us but also about who we are. Despite its relative historical neglect, recent work in epistemology has seen a growing recognition of the importance and scope of testimonial knowledge. Most of this work has focused on two central questions, which will be the main topics of this article. First, is testimonial knowledge necessarily acquired through transmission from speaker to hearer, or can testimony generate epistemic features in its own right? Second, is justified dependence on testimony fundamentally basic, or is it ultimately reducible to other epistemic sources, such as perception, memory, and reason? Testimony itself is typically understood quite broadly so as to include a variety of acts of communication that are intended or taken to convey information—such as statements, nods, pointings, and so on. (For a full development of this view, see Lackey 2008.) Knowledge that is distinctively testimonial requires belief that is based or grounded in, not merely caused by, an instance of testimony. For instance, suppose that I sing “I have a soprano voice” in a soprano voice and you come to believe this entirely on the basis of hearing my soprano voice. (This is a variation of an example found in Audi 1997.) While my testimony is certainly causally relevant to the formation of your belief, the resulting knowledge is based on your hearing my soprano voice rather than on what I testified to, thereby rendering it perceptual in nature. What is of import for distinctively testimonial knowledge is that a given belief be formed on the basis of the content of a speaker’s testimony. This prevents beliefs that are formed entirely on the basis of features about a speaker’s testimony from qualifying as instances of testimonial knowledge.

Immanuel Kant is often regarded as an exponent of the ‘individualist’ tradition in epistemology, according to which testimony is not a fundamental source of knowledge. The present paper argues that this view is far from accurate. Kant devotes ample space to discussions of testimony and, in his lectures on logic, arrives at a distinct and stable philosophical position regarding testimony. Important elements of this position consist in (a) acknowledging the ineliminability of testimony; (b) realizing that testimony can establish empirical knowledge with certainty; (c) establishing a presumptive principle regarding the acceptance of testimony; (d) arguing for a symmetry between knowledge based on experience and knowledge based on testimony. Rejecting testimony as a fundamental source of knowledge merely on the basis that no theoretically necessary ground for its truth can be given, would, as Kant puts it, indicate ‘a lack of moral interest’. Such ‘incredulity’ would be a form of ‘logical egoism’: it demonstrates an unwillingness or inability to think oneself in the place of others, yet this we must do if we are to trust our own judgements. While Kant strongly endorses testimony as a source of empirical knowledge, he does, however, make one important restriction: ‘Propositions of reason’ (Vernunftwahrheiten), such as universal moral principles, may not be adopted on the basis of testimony. I argue that this distinction, between testimonial knowledge of empirical matters of fact and individual knowledge of propositions of reason, is an important element of Kant’s epistemology of testimony, as it explains how his strong endorsement of testimony as a source of knowledge can be squared with his equally strong demand for intellectual autonomy. Finally, I comment on the overall implications of this account for Kant’s discussion, elsewhere in his work, of the public nature of communication.

Testimony is an invaluable source of knowledge. We rely on the reports of those around us for everything from the ingredients in our food and medicine to the identity of our family members. Recent years have seen an explosion of interest in the epistemology of testimony. Despite the multitude of views offered, a single thesis is nearly universally accepted: testimonial knowledge is acquired through the process of transmission from speaker to hearer. In this book, Jennifer Lackey shows that this thesis is false and, hence, that the literature on testimony has been shaped at its core by a view that is fundamentally misguided. She then defends a detailed alternative to this conception of testimony: whereas the views currently dominant focus on the epistemic status of what speakers believe, Lackey advances a theory that instead centers on what speakers say. The upshot is that, strictly speaking, we do not learn from one another's beliefs - we learn from one another's words. Once this shift in focus is in place, Lackey goes on to argue that, though positive reasons are necessary for testimonial knowledge, testimony itself is an irreducible epistemic source. This leads to the development of a theory that gives proper credence to testimony's epistemologically dual nature: both the speaker and the hearer must make a positive epistemic contribution to testimonial knowledge. The resulting view not only reveals that testimony has the capacity to generate knowledge, but it also gives appropriate weight to our nature as both socially indebted and individually rational creatures. The approach found in this book will, then, represent a radical departure from the views currently dominating the epistemology of testimony, and thus is intended to reshape our understanding of the deep and ubiquitous reliance we have on the testimony of those around us.

Testimony is an invaluable source of knowledge. We rely on the reports of those around us for everything from the ingredients in our food and medicine to the identity of our family members. Recent years have seen an explosion of interest in the epistemology of testimony. Despite the multitude of views offered, a single thesis is nearly universally accepted: testimonial knowledge is acquired through the process of transmission from speaker to hearer. In this book, Jennifer Lackey shows that this thesis is false and, hence, that the literature on testimony has been shaped at its core by a view that is fundamentally misguided. She then defends a detailed alternative to this conception of testimony: whereas the views currently dominant focus on the epistemic status of what speakers believe, Lackey advances a theory that instead centers on what speakers say. The upshot is that, strictly speaking, we do not learn from one another's beliefs - we learn from one another's words. Once this shift in focus is in place, Lackey goes on to argue that, though positive reasons are necessary for testimonial knowledge, testimony itself is an irreducible epistemic source. This leads to the development of a theory that gives proper credence to testimony's epistemologically dual nature: both the speaker and the hearer must make a positive epistemic contribution to testimonial knowledge. The resulting view not only reveals that testimony has the capacity to generate knowledge, but it also gives appropriate weight to our nature as both socially indebted and individually rational creatures. The approach found in this book will, then, represent a radical departure from the views currently dominating the epistemology of testimony, and thus is intended to reshape our understanding of the deep and ubiquitous reliance we have on the testimony of those around us.

Can one gain testimonial knowledge from unsafe testimony? It might seem not, on the grounds that if a piece of testimony is unsafe, then any belief based on it in such a way as to make the belief genuinely testimonial is bound itself to be unsafe: the lack of safety must transmit from the testimony to the testimonial belief. If in addition we accept that knowledge requires safety, the result seems to be that one cannot gain testimonial knowledge from unsafe testimony. In a pair of recent papers, however, Sanford Goldberg has challenged this apparently plausible line of thought. Goldberg presents two examples intended to show that a testimonial belief can be safe, even if the testimony on which it is based is unsafe: the lack of safety need not transmit from the testimony to the testimonial belief. In this paper, I question whether Goldberg’s examples really do show that one can gain safe testimonial belief from unsafe testimony. The problem, I explain, is that both examples appear (for different reasons) to be open to objection. Nevertheless, I argue that although Goldberg’s examples do not establish his conclusion, the conclusion itself is true: one can gain safe testimonial belief from unsafe testimony. I base my argument on an example which differs in structure from Goldberg’s examples, and I argue that due to this difference, my example avoids the problems which Goldberg’s examples face.

An adequate account of testimonial knowledge in general explains how religious knowledge can be grounded in testimony, and even in the context of conflicting testimonial traditions. Three emerging trends in epistemology help to make that case. The first is to make a distinction between two projects of epistemology: “the project of explanation” and “the project of vindication.” The second is to emphasize a distinction between knowledge and understanding. The third is to ask what role the concept of knowledge plays in our conceptual-linguistic economy. Each of these trends, it is argued, helps us to make progress in the epistemology of testimony, and by application in the epistemology of religious belief.