Abstract
Philosophical lessons come in many different shapes and sizes. Some lessons are big, some are small. Some lessons go deep and have a big impact, some are shallow and have almost none. Some lessons are not really philosophical at all or would not really be lessons for an audience of academic philosophers. I mention these truisms not to disparage this informative book on 'moral OCD' (moral obsessive-compulsive disorder, or 'Scrupulosity') but rather to emphasize how difficult it can be to discern the book's intended audience, given its interdisciplinary aims and structure. That question is never explicitly addressed (it is admittedly a slim book, slimmer than it appears), but the question has consequences for how to think about the book's ultimate value, and for whom. The book might attract two groups in particular: philosophers working on the nature of responsibility (the subject of the book's longest chapter) and psychiatric researchers or mental health professionals interested in moral philosophy and the philosophy of mental illness. I will return to what moral philosophers can learn from moral OCD, but there will be spoilers.