ABSTRACT
Is there an essential “nature” in which all human beings share? If so, do biotechnological forms of human enhancement threaten to violate human nature? Proposed answers to these questions have divided those who reject any non-therapeutic interventions that could alter the putatively definitive qualities of human nature from those who argue in favor of the freedom to reshape oneself in any non-harmful way one chooses. Between these diametrically opposed positions are several proposals that allow for certain forms of enhancement that may increase individual or collective well-being within the limits of a defined human nature. This chapter begins by considering why an account of human nature is needed to engage adequately with questions concerning human enhancement. It then canvasses several views of human nature that have informed diverse perspectives on the ethics of enhancement. Particular attention is given to how some forms of cognitive enhancement may impact one's personal identity, as well as how some forms of moral enhancement may impact one's narrative identity. The chapter concludes that the question of what constitutes human nature and the identity of human persons through time and change is indispensable for continued investigation into the ethics of various enhancement proposals.
