 Despite the fact that much of the contemporary philosophical discussion of self-deception has focused on epistemology, philosophical psychology and philosophy of mind, the morality of self-deception has been the central focus of discussion historically. As a threat to moral self-knowledge, a cover for immoral activity, and a violation of authenticity, self-deception has been thought to be morally wrong or, at least, morally dangerous. Some thinkers, what Martin (1986) calls ‘the vital lie tradition’, however, have held that self-deception can in some instances be salutary, protecting us from truths that would make life unlivable (e.g., Rorty 1972; 1994). There are two major questions regarding the morality of self-deception: First, can a person be held morally responsible for self-deception and if so under what conditions? Second, is there is anything morally problematic with self-deception, and if so, what and under what circumstances? The answers to these questions are clearly intertwined. If self-deceivers cannot be held responsible for self-deception, then their responsibility for whatever morally objectionable consequences it might have will be mitigated if not eliminated. Nevertheless, self-deception might be morally significant even if one cannot be taxed for entering into it. To be ignorant of one’s moral self, as Socrates saw, may represent a great obstacle to a life well lived whether or not one is at fault for such ignorance.