Of course, human beings in the embryonic, fetal and early infant stages cannot yet exercise mental functions characteristically carried out by most human beings at later stages of maturity. Still, they have in radical—that is, root form—these very capacities. Precisely by virtue of the kind of entity they are, they are, from the beginning, actively developing themselves to the stages at which these capacities will—if all goes well—be immediately exercisable. Although, similar to infants, they have not yet developed themselves to the stage at which they are self-aware, it is clear that they are rational animal organisms. Having a rational nature is, in the words of Jeff McMahan at Rutgers University (New Brunswick, NJ, USA) a “status-conferring intrinsic property”. The argument is not that every member of the human species should be accorded full moral respect because the more mature members of the species have a status-conferring intrinsic property, as McMahan mistakenly interprets the nature-of-the-kind argument. Instead, we contend that each member of the human species has a rational nature.
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