This chapter states the contrast between presumptivism about testimonial warrant (often called anti-reductionism) and strict reductionism (associated with Hume) about testimonial warrant. Presumptivism sees an analogy with modest foundationalism about perceptual warrant. Strict reductionism denies this analogy. Two theoretical frameworks for these positions are introduced to better formulate the most popular version of persumptivism, a competence reliabilist account. Seven arguments against presumptivism are then stated and critiqued: (1) The argument from reliability; (2) The argument from reasons; (3) the argument from (...) positive reasons; (4) the argument from negative reasons; (5) the argument from agency; (6) the argument from psychological force; and (7) the argument from gullibility. If presumptivm is false, it is not for any of these arguments. (shrink)

Several influential thought experiments from Harman 1973 purport to show that unpossessed evidence can undermine knowledge. Recently, some epistemologists have appealed to these thought experiments in defense of a logically stronger thesis: unpossessed evidence can defeat justification. But these appeals fail to appreciate that Harman himself thought of his examples as Gettier cases, and so would have rejected this strengthening of his thesis. On the contrary, he would have held that while unpossessed evidence can undermine knowledge, it leaves justification intact. (...) In this paper I seek to undermine the viability of Harman’s position. If this is correct, contemporary epistemology faces a choice: either we reject that unpossessed evidence in Harman-style cases bears on knowledge _at all_, or else we must allow that it undermines knowledge _by defeating justification_. The former option must explain why Harman’s thought experiments elicit strong ‘no knowledge’ intuitions; the latter option embraces a minority view about the bearing of social expectations on the assessment of knowledge _and justification_ (= the doctrine of normative defeat). (shrink)

Social knowledge, for the most part, is knowledge through testimony. This essay is an overview of the epistemology of testimony. The essay separates knowledge from justification, characterizes testimony as a source of belief, explains why testimony is a source of knowledge, canvasses arguments for anti-reductionism and for reductionism in the reductionism vs. anti-reductionism debate, addresses counterexamples to knowledge transmission, defends a safe basis account of testimonial knowledge, and turns to social norms as a partial explanation for the reliability of testimony.