Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Philosophy (PhD)

Degree Level





Thomas D. Senor

Committee Member

Edward Minar

Second Committee Member

Jack Lyons


Philosophy, religion and theology, Disagreement, Everyday lives, Interactions with opponents, Personal discernment


Suppose that you and an intellectual peer disagree about some proposition P in a field like philosophy, ethics, science, religion, politics, etc. As intellectual peers, they are roughly of equal intelligence and equally virtuous with respect to evaluating the evidence E in support of P. What is the epistemic significance of you and an intellectual `peer' disagreeing about whether some body of evidence E supports a given proposition P? Can two epistemic peers reasonably disagree? In Chapter 1, I consider the Equal Weight View according to which rationality requires you to give equal weight to you peer's response to the evidential support for P. When you do, both parties will be required to either suspend judgment about P or radically modify their doxastic stance in the direction of their peer. Since there is only one rational doxastic stance with respect to P, two intellectual peers cannot reasonably disagree. I offer numerous objections to the Equal Weight View. In Chapter 2, I consider the Total Evidence View as articulated by Thomas Kelly. He argues that when an impeccable reasoner disagrees with a consensus of his peers, rationality requires him to reduce his level of confidence in P. I argue that consensus is not sufficient to warrant a reduction in confidence. In Chapter 3, I consider a third type of view I call "Steadfastness" according to which it is reasonable for an agent to stand firm in his response to E's support of P. Here we discover that there are a variety of token-instances of steadfastness. In Chapter 4, I extend my account by arguing that Steadfastness is a cognitive virtue that helps an agent stand her ground with respect to P while she integrates her newly acquired evidence. My view is unique in its emphasis on diachronic features of epistemic rationality as opposed to synchronic ones. Two upshots are that we can have reasonable disagreements and maintain our beliefs in a number of areas of intractable disagreement.