Jonathan Matheson

The Uniqueness Thesis, or rational uniqueness, claims that a body of evidence severely constrains one’s doxastic options. In particular, it claims that for any body of evidence E and proposition P, E justifies at most one doxastic attitude toward P. In this paper I defend this formulation of the uniqueness thesis and examine the case for its truth. I begin by clarifying my formulation of the Uniqueness Thesis and examining its close relationship to evidentialism. I proceed to give some motivation for this strong epistemic claim and to defend it from several recent objections in the literature. In particular I look at objections to the Uniqueness Thesis coming from considerations of rational disagreement (can’t reasonable people disagree?), the breadth of doxastic attitudes(can’t what is justified by the evidence encompass more than one doxastic attitude?), borderline cases and caution (can’t it be rational to be cautious and suspend judgment even when the evidence slightly supports belief?), vagueness (doesn’t the vagueness of justification spell trouble for the Uniqueness Thesis?), and degrees of belief (doesn’t a finegrained doxastic picture present additional problems for the Uniqueness Thesis?).

An introduction to the debate of the epistemic significance of peer disagreement. This article examines the epistemic significance of peer disagreement. It pursues the following questions: (1) How does discovering that an epistemic equal disagrees with you affect your epistemic justification for holding that belief? (e.g., does the evidence of it give you a defeater for you belief?) and (2) Can you rationally maintain your belief in the face of such disagreement? This article explains and motivates each of the central positions, including steadfast views and conciliatory views of peer disagreement, while at the same time raising challenges for each of them. It concludes by speculating about new directions that the debate will take.

Much of the literature on the epistemology of disagreement focuses on the rational responses to disagreement, and to disagreement with an epistemic peer in particular. The Equal Weight View claims that in cases of peer disagreement each dissenting peer opinion is to be given equal weight and, in a case of two opposing equally-weighted opinions, each party should adopt the attitude which ‘splits the difference’. The Equal Weight View has been taken by both its critics and its proponents to have quite drastic skeptical ramifications given contingent empirical facts that we are aware of regarding disagreements in philosophy, religion, science, and politics. In this paper,we begin by clarifying the central claims of the Equal Weight View (Section 2) and then examine two routes from the Equal Weight View to skepticism about such matters that have been explored in the literature. The first claims that our awareness of peers or experts who disagree with us about such issues requires that we abandon our beliefs on these issues (Section 3). The second claims that our awareness of merely possible peers or experts who disagree with us requires us to abandon our beliefs (Section 4). We find both routes from the Equal Weight View to a form of skepticism defective. However, there are nearby considerations, explored in Sections 5 and 6,which (for better or worse) do lead to at least some skeptical consequences for the Equal WeightView, albeit for different reasons.

The generality problem is perhaps the most notorious problem for process reliabilism. Several recent responses to the generality problem have claimed that the problem has been unfairly leveled against reliabilists. In particular, these responses have claimed that the generality problem is either (i) just as much of a problem for evidentialists, or (ii) if it is not, then a parallel solution is available to reliabilists. Along these lines, Juan Comesaña has recently proposed solution to the generality problem—well-founded reliabilism. According to Comesaña, the solution to the generality problem lies in solving the basing problem, such that any solution to the basing problem will give a solution to the generality problem. Comesaña utilizes Conee and Feldman’s evidentialist account of basing (Conee and Feldman’s well-foundedness principle) in forming his version of reliabilism. In this paper I show that Comesaña’s proposed solution to the generality problem is inadequate. Well-founded reliabilism both fails to solve the generality problem and subjects reliabilism to new damning verdicts. In addition, I show that evidentialism does not face any parallel problems, so the generality problem remains a reason to prefer evidentialism to reliabilism

Conciliatory views of disagreement are an intuitive class of views on the epistemic significance of disagreement. Such views claim that making conciliation is often required upon discovering that another disagrees with you. One of the chief objections to these views of the epistemic significance of disagreement is that they are self-defeating. Since, there are disagreements about the epistemic significance of disagreement, such views can be turned on themselves, and this has been thought to be problematic. In this paper, I examine several different incarnations of this objection and defend conciliatory views of disagreement from each of them, while making a modification regarding how such views should be understood

Michael Bergmann claims that all versions of epistemic internalism face an irresolvable dilemma. We show that there are many plausible versions of internalism that falsify this claim. First, we demonstrate that there are versions of ‘‘weak awareness internalism’’ that, contra Bergmann, do not succumb to the ‘‘Subject’s Perspective Objection’’ horn of the dilemma. Second, we show that there are versions of ‘‘strong awareness internalism’’ that do not fall prey to the dilemma’s ‘‘vicious regress’’ horn. We note along the way that these versions of internalism do not, in avoiding one horn of the dilemma, succumb to the dilemma’s other horn. The upshot is that internalists have many available strategies for avoiding dilemmatic defeat.

While puzzles concerning the epistemic significance of disagreement are typically motivated by looking at the widespread and persistent disagreements we are aware of, almost all of the literature on the epistemic significance of disagreement has focused on cases idealized peer disagreement. This fact might itself be puzzling since it doesn’t seem that we ever encounter disagreements that meet the relevant idealized conditions. In this paper I hope to somewhat rectify this matter. I begin by closely examining what an idealized case of peer disagreement looks like and what the Equal Weight View (EWV) of disagreement claims about the epistemic significance of such disagreements. After briefly defending the verdicts of the EWV in idealized disagreements I proceed to unpack the implications of stripping away the idealized conditions. In doing I show both why it is important to focus on idealized cases of peer disagreement and what we can learn from such cases that applies to the everyday cases of disagreement of which we are very familiar.