Online research in philosophy

Various considerations are adduced toshow that we require that a testifier know hertestimony. Such a requirement apparentlyimproves testimony. It is argued that the aimof improving testimony explains why we have anduse our concept of knowledge. If we were tointroduce a term of praise for testimony, usingit at first to praise testimony that apparentlyhelped us in our practical projects, it wouldcome to be used as we now use the word``know''.

I discuss several views of the nature of testimony and show how each proposal has importantly different problems. I then offer a diagnosis of the widespread disagreement regarding this topic; specifically, I argue that our concept of testimony has two different aspects to it. Inadequate views of testimony, I claim, result either from collapsing these two aspects into a single account or from a failure to recognize one of them. Finally, I develop an alternative view of testimony that captures both aspects of the nature of testimony and thereby provides the basis for an illuminating theory of testimony's epistemological significance.

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.

Testimony is the mainstay of human communication and essential for the spread of knowledge. But testimony may also spread error. Under what conditions does it yield knowledge in the person addressed? Must the recipient trust the attester? And does the attester have to know what is affirmed? A related question is what is required for the recipient to be justified in believing testimony. Is testimony-based justification acquired in the same way as testimony-based knowledge? This paper addresses these and other questions. It offers a theory of the role of testimony in producing knowledge and justification, a sketch of a conception of knowledge that supports this theory, a brief account of how trust of others can be squared with critical habits of mind, and an outline of some important standards for intellectual responsibility in giving and receiving testimony.

According to the “Folieism” I have been recently defending, communication is a kind of folie à deux in which speakers and hearers enjoy a stable and innocuous illusion of producing and hearing standard linguistic entities (“SLE”s) that are seldom if ever actually produced. In the present paper, after summarizing the main points of the view, I defend it against efforts of Barber, Devitt and Miščević to rescue SLEs in terms of social, response-dependent proposals. I argue that their underlying error is a failure to appreciate the important shift of the explanatory locus in modern linguistics, from external objects to internal conceptions. I go on to show how (i) pace Devitt, this shift is entirely compatible with there being conventional aspects to language, and also serves to distinguish the ease of natural language from the waggle dance of the bees; and (ii) pace Barber and Smith, it is compatible with an appearance / reality distinction, and with reliance on testimony in epistemology. I conclude with further arguments about why, pace Collins and Matthews, intentionality is a crucial feature of linguistic explanation, even if it is ultimately spelt out largely in terms of computational role.

I defend the acceptance principle for testimony (APT), that hearers are justified in accepting testimony unless they have positive evidence against its reliability, against Elizabeth Fricker's local reductionist view. Local reductionism, the doctrine that hearers need evidence that a particular piece of testimony is reliable if they are to be justified in believing it, must on pain of scepticism be complemented by a principle that grants default justification to some testimony; I argue that (APT) is the principle required. I consider two alternative weaker principles as complements to local reductionism; one yields counter-intuitive results unless we accept (APT) as well, while the other is too weak to enable local reductionism to avoid scepticism.

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.

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.

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.

Against criticism from Georges Rey I defend both my earlier account of sentence realization and my objection to his own ‘folie-a-deux’ account. The latter has two components, one sceptical (sentences and other standard linguistic entities are rarely if ever realized [‘produced’, ‘tokened’, ‘uttered’]) and the other optimistic (this is a benign outcome since communication is unaffected by our being mistaken in assuming that they are realized). Both components are flawed, notwithstanding Rey’s defence. My non-sceptical account of sentence realization avoids the difficulties his faces, as well as those he raises for it.