Testimony: Evidence and Responsibility

Testimony is an indispensable way of gaining knowledge and also a voluntary act for which the teller can be held responsible. This dissertation analyzes these two aspects of testimony, the epistemological and the normative. Indeed, it argues that these two aspects cannot be separated: A satisfactory account of testimony's epistemology must allow for testimony's normative status, while an account of testimony's normative status can be derived from testimony's epistemology. ;Epistemologically, the general reliability of testimony should be treated differently from the reliability of particular pieces of testimony. We are justified in believing that testimony is generally reliable, without needing evidence to that effect. This avoids the problems that would arise from attempting to gather evidence for testimony's general reliability. Particular pieces of testimony, however, can only provide a justification for belief by providing evidence for what is told. This view about particular pieces of testimony faces the problem of how the teller can present her testimony as evidence while accepting responsibility for it, and how the hearer can take testimony as evidence while holding the hearer responsible for it. ;To solve this problem, I give an account, based on inference to the best explanation, of the specific way testimony provides evidence for what is told. To see testimony as evidence for what is told, we must explain it in terms of the reasons people have for choosing to say one thing rather than another. On this account, the evidence that testimony provides depends on the teller's choice to assume responsibility for her testimony, rather than precluding that assumption of responsibility. ;On the other hand, the epistemology of testimony imposes certain norms on the act of telling someone something. The teller is responsible for the truth of her testimony, in that she stakes her future credibility on its truth. Loss of credibility would count as a sanction for violating the responsibility to tell the truth, because a teller ordinarily intends her testimony to be believed. This responsibility to tell the truth is derived from the epistemology of testimony