Abstract
This chapter explores how far one can go accounting for the moral responsibility implications of several unusual mental conditions using a parsimonious quality-of-will account that relies on the way we talk about moral responsibility in more mundane situations. By contrasting situations involving epistemic irrationality versus cognitive impairment, it becomes clear that the presence of those often (but not always) excuses actions performed by unusual agents. The discussion turns to cases of clinical depression and sketches a way for quality-of-will accounts to approach them. It is also argued that of some of these mental conditions, there is no particular reason to think that they excuse. There is also an argument against regarding the concept "mental disorder" and current DSM categories as critical to agency theory.