Date of Award

Spring 1-1-2018

Document Type


Degree Name

Doctor of Philosophy (PhD)

First Advisor

Graham Oddie

Second Advisor

Alastair Norcross

Third Advisor

Michael Tooley


The problem of moral uncertainty can be described as the problem of what an agent ought to do when they are uncertain what the morally right thing to do is, and their uncertainty about how to act stems from uncertainty about moral facts salient to their decision. There are, broadly speaking, three responses to this problem. According to the first, agents ought to consider the moral tradeoffs of their prospective actions. That is, they ought to consider not only the likelihood of one action being better than others, but also how much morally better or worse it would be to choose one action rather than another, given their uncertainty. One way to do this is to maximize the expected moral value of one’s actions. This is precisely the response to the problem of moral uncertainty that I refine and defend in this dissertation.

In the first paper, I present objections to an opposing view in the literature that rejects the entire project of giving a unique normative theory for moral uncertainty. I argue that two of the reasons cited in favor of this position by its proponents are in fact points of embarrassment for the position. In the second paper, I defend my response to the problem of moral uncertainty from an objection, according to which my response has counterintuitive implications for moral praise and blame-worthiness. I argue that this objection only succeeds against a very particular fine-grained version of my response, a version which no one in fact defends. Also in this paper, I use this objection as an opportunity to clarify and refine my position in the literature. In the third and final paper, I defend my position against two significant objections in the literature. I argue that both objections rely on a flawed way of modelling decision-making under moral uncertainty. I offer an alternative, superior model. On this model, these two objections disappear. A competing theory to my own is thus in serious trouble as a primary motivation for this view was the seeming intractability of the one of the objections that I dispatch.