When peers disagree: An essay in the epistemology of peer disagreement

My aim in this dissertation is to contribute to the existing literature on the epistemology of peer disagreement. Toward that end, I do the following.;In Chapter 1, I consider and reject a number of proposed characterizations of the concept of disagreement. I then present and defend the following analysis: For any two individuals S1 and S2, any proposition p, and any time t, S1 and S2 disagree over p at t if and only if S1 and S2 take different doxastic attitudes toward p at t.;In Chapter 2, I analyze the concept of epistemic peers in part by appealing to the notion of epistemic credentials. I then note the various epistemic credentials relevant to determining epistemic peers (allowing that there may be more): justification peers, truth peers, knowledge peers, responsible inquiry peers, and information peers. I then argue (contrary to the dominant stream in the literature) that the epistemology of peer disagreement literature is best served by invoking the epistemic credential found in the concept of truth peers: For any two individuals S1 and S2, any time t, and any proposition p, S1 and S2 are truth peers at t about p if and only if S1 and S2 are equally fit at t for attaining a true belief about p. I then argue that, from among the popular competitors found in the current literature, it alone is the epistemic credential relevant to epistemic peer sufficient to raise, in a particularly compelling way, the interesting epistemological question about justification found in the literature.;In Chapter 3, I do two things. First, I present and clarify one particular position advanced in the current epistemology of peer disagreement literature, namely, The Equal Weight View (EWV): For any persons S1 and S2, any proposition p and any time t, if S1 and S2 are in a peer encounter over p at t, then the opinions of S1 and S2 about pat t are worth the same evidentially. Second, I defend EWV from an objection based on The Uniqueness Thesis.;In Chapter 4, I do two things. First, I defend EWV from the objection that it swamps the original evidence in cases of peer encounter. Second, I defend EWV from the charge that it has theoretical similarities with an implausible view about how to handle (rationally) intrapersonal conflict.;In Chapter 5, I defend EWV from the charge that it licenses objectionable forms of bootstrapping. Once again, I argue that EWV has no such implications. Moreover, taking the view that peer testimony is epistemically decisive in (standard) cases of peer encounter doesn't commit one to objectionable bootstrapping. Whatever bootstrapping it does allow is not, upon reflection, objectionable.;In Chapter 6, I do two things. I defend EWV from the charge that it makes implausible distinctions between kinds of evidence. I argue that EWV all by itself makes no evidential distinctions of any kind. Second, I defend EWV from the objection that it makes it implausibly difficult to demote an individual from epistemic peer to inferior simply on the basis of (perhaps repeated) disagreements.;Finally, in Chapter 7, I do two things. First, I defend EWV from the charge that it is rationally self-undermining. I argue that EWV is not rationally self-undermining since by itself it makes no claims about what it is rational to believe.;Second, I defend EWV from the objection that it badly mishandles several cases in the literature, namely, Careful Checking and Extreme Mental Math. I do this in a roundabout way. I take the claim that peer testimony is epistemically decisive in cases of peer encounter. I then consider two different cases in the literature: Elementary Math and Perception. I argue that these cases are no trouble for the view that peer testimony is epistemically decisive in cases of peer encounter, and that considering these cases brings out some helpful points that can then be brought to bear on Careful Checking and Extreme Mental Math. (Abstract shortened by UMI.).