 A number of philosophers have argued for the full moral status of all human beings, without seeking to identify any attribute possessed by all humans that would ground that status. These philosophers can be roughly divided into two groups. Those in the first group regard membership in the species Homo sapiens as sufficient for full moral status and ground that status in a species-based attribute (See  Sec. 5.1).  For some philosophers within this first group, all homo sapiens belong to a kind whose nature or norm it is to possess rationality or similar attributes  (Sec. 5.1.1).  For others, all homo sapiens are connected through “ties of birth” to other human beings  (Sec. 5.1.2).  For the former, any being of a kind whose nature it is to be rational, etc. has full moral status; for the latter, any human related by birth to other human beings has full moral status. Although the two approaches pick out the same individual human beings, the way in which they ground moral status gives them different implications for the status of human beings with radical cognitive impairments.