Abstract
Current and future possibilities for enhancing human physical ability, cognition, mood, and lifespan raise the ethical question of whether we should enhance normal human capacities in these ways. This chapter offers such an account of enhancement. It begins by reviewing a number of suggested accounts of enhancement, and points to their shortcomings. The chapter then identifies two key senses of “enhancement”: functional enhancement, the enhancement of some capacity or power (e.g. vision, intelligence, health) and human enhancement, the enhancement of a human being's life. The latter notion is the notion of enhancement most relevant to ethical debate. The chapter argues that it is best understood in welfarist terms. It illustrates this welfarist approach to enhancement by applying it to the case of cognitive enhancement. Unlike the sociological pragmatic and functional approaches, the welfarist account is inherently normative. It ties enhancement to the value of well‐being.