Lying is a common phenomenon amongst human beings. It seems to play a role in making social interactions run more smoothly. Too much honesty can be regarded as impolite or downright rude. Remarkably, lying is not a common phenomenon amongst normally intelligent human beings who are on the autism spectrum. They appear to be ‘attractively morally innocent’ and seem to have an above average moral conscientious objection against deception. In this paper, the behavior of persons with autism with regard to (...) deception and truthfulness will be discussed in the light of two different ethical theories, illustrated by fragments from autobiographies of persons with autism. A systemizing ‘Kantian’ and an empathizing ‘ethics of care’ perspective reveal insights on high-functioning autism, truthfulness and moral behavior. Both perspectives are problematic from the point of view of a moral agent with autism. High-functioning persons with autism are, generally speaking, strong systemizes and weak empathizers. Particularly, they lack ‘cognitive empathy’ which would allow them to understand the position of the other person. Instead, some tend to invent a set of rules that makes their behavior compatible with the expectations of others. From a Kantian point of view, the autistic tendency to always tell the truth appears praiseworthy and should not be changed, though it creates problems in the social life of persons with autism. From a care ethics perspective, on the other hand, a way should be found to allow the high-functioning persons with autism to respect the feelings and needs of other persons as sometimes overruling the duty of truthfulness. We suggest this may even entail ‘morally educating’ children and adolescents with autism to become socially skilled empathic ‘liars’. (shrink)