Three features of human nature are at the center of many debates about the ethics of biomedical enhancement. The first feature is human vulnerability. According to one prominent view, human beings are creatures that suffer, age and die, and our struggle to deal with this vulnerability is a central aspect of what makes human life valuable (Parens 1995). There are several sub-groups within the group of theorists that emphasize the value of vulnerability in understanding the value of being human. The first group consists of “life cycle traditionalists” who criticize ambitions to control the human ageing process and extend the human life span (Callahan 1995). The second group consists of the “personalists”, who valorize the way in which human limitations are humbling and encourage modesty (Fitzgerald 2008). The third group consists of “psychopharmaceutical Calvinists” who discourage easy fixes to melancholy and sadness (Elliot 1998). The second feature of human nature that is emphasized in these debates is discussed by species preservationists and environmentalists who stress our embodiment and place in nature alongside other organisms: “by nature”, we are biological creatures of a particular family, defined by painfully evolved “species barriers”, and enhancements that blur or bend those boundaries by “directing evolution” do so at our peril (McKibben 2004). The third feature of human nature that is often discussed in these debates is our sociality. According to these theorists, human beings are social creatures that relate to one another through a complex nexus of interpersonal commitments and hierarchical structures (Liao 2006a; Liao 2006b). Many sports theorists see the “virtuous perfection of natural talents” as the goal of athletic competitions. If one accepts this view, then victories fueled by biomedical enhancements that subvert the natural interpersonal hierarchies that genetic disparities in talent create can literally “dehumanize” sport (Tolleneer, Steryck and Bonte 2013).