Varieties of Moral Mistake

Some philosophers think that if someone acts wrongly while falsely believing that her act is permissible, this moral mistake cannot excuse her wrongdoing. And some think that this is because it is morally blameworthy to fail to appreciate the moral significance of non-moral facts of which one is aware, such that mistakenly believing that one's act is permissible when it is in fact wrong is itself morally blameworthy. Here I challenge the view that it is blameworthy to fail to appreciate the moral significance of non-moral facts of which one is aware. This view seems okay if we focus on examples of people mistakenly believing that their wrongful acts are permissible. But it is not remotely plausible when we consider other varieties of moral mistake - such as believing that one's action is required when it is in fact supererogatory, believing that one's action is wrong when it is in fact permissible, and believing false things about the moral properties of others' actions and of merely possible actions. The upshot is that those who maintain that moral mistakes cannot excuse are sent back to the drawing board; we need a new explanation of why this would be the case.