 One source of controversy concerns the scope of the concept of a person. Although in everyday discourse the word “person” is synonymous with “human being,” some philosophical discussions treat it as a technical term whose range of application might not be coextensive with the class of human beings (just as, for legal purposes, business corporations are regarded as persons). This is because some of the reasons that have been given for respecting persons entail both that some non-human things warrant the same respect on the very same grounds as humans and that not all humans do. Consequently, one question an account of respect for persons has to address is: Who or what are persons that are owed respect? Different answers have been offered, including all human beings; all and only those humans who are themselves capable of respecting persons; all beings capable of rational activity, or of sympathy and empathy, or of valuing, whether human or not; all beings capable of functioning as moral agents, whether human or not; all beings capable of participating in certain kinds of social relations, whether human or not. The second, third, and fourth answers would seem to exclude deceased humans and humans who lack sufficient mental capacity, such as the profoundly mentally disabled, the severely mentally ill and senile, those in persistent vegetative states, the pre-born, and perhaps very young children. The third, fourth, and fifth answers might include humans with diminished capacities, artificial beings (androids, sophisticated robots), spiritual beings (gods, angels), extraterrestrial beings, and certain animals (apes, dolphins).