 Humanists are wary of grounding the full moral status of radically-impaired humans in their relationship to a species-norm like rationality. Thus, Byrne (2000) argues that appeal to the rational nature of human beings as the basis for respect is too reliant on external justification and too narrow. It is too reliant on claims about the respect owed to beings that are rational-by-nature, which Byrne doubts are any more self-evident or plausible than claims about the respect owed human beings. It is too narrow because it ignores other aspects of humanity that make the concept of “human being” so rich and powerful.