dissertation

My area of research, broadly construed, is the nature of rationality. In my dissertation, I focus on the question of whether rationality is permissive: that is, the question of whether a single body of evidence can ever rationalize more than one doxastic attitude towards a hypothesis. If rationality is permissive, then there are cases in which two people with the same evidence can have conflicting doxastic attitudes – for example, suspension of judgment and belief – toward some hypothesis. If rationality is impermissive, it only ever permits a single doxastic response to the evidence. I argue that rationality is permissive, but in an unexpected way: cases in which a body of evidence justifies multiple, incompatible responses (permissive cases) exist, but a subject who is in such a case can never rationally believe that she is in one. This view has sometimes been referred to as unacknowledged permissivism (UP). My dissertation contributes to the field by showing that there is a strong, independent case for unacknowledged permissivism, contrary to what virtually all philosophers who have recognized the theoretical possibility of unacknowledged permissivism have assumed.

My defense of UP has two major components. First, I argue that there is a compelling case that rationality is permissive arising from theoretical considerations. The second component of my defense of unacknowledged permissivism involves establishing the ‘unacknowledged’ aspect of unacnkowledged permissivism. I argue that there is a coherence requirement of rationality that prohibits a subject from believing some proposition P on the basis of evidence E while also believing that an incompatible doxastic attitude toward P is rational on the basis E. I argue for this position by showing that a subject who believes such a conjunction is committed to a kind of intrapersonal incoherence that, in other cases, is obviously rationally problematic. If this is correct, there is a compelling case for the conclusion that believing one is in a permissive case is rationally prohibited, and thus a compelling case that unacknowledged permissivism is correct.

Among those writing on the question of whether rationality is permissive, there is general consensus that either impermissivism or acknowledged permissivism is correct. Of those authors who recognize the possibility of unacknowledged permissivism, virtually all dismiss it as implausible. The orthodox view is that UP is an unmotivated position, in part because it is said to break ties with the core motivation for defending permissivism in the first place – namely, our intuitions about cases describing disagreement between peers. I challenge the dominant view, arguing that, contrary to what has been assumed, our intuitions about these cases are compatible with unacknowledged permissivism. I also argue that UP derives further plausibility from its immunity to the most serious objection to permissivism, the inconsistency problem. If unacknowledged permissivism is true, it reveals something interesting about the nature of rationality: that it imposes a limit on what I am able to believe or know about the character of my own evidence that does not apply to others.