New technologies are likely to emerge in the coming decades that significantly enhance humans’ biology. But there are many examples in recent human history of new inventions, such as leaded petrol and asbestos, that are released to the public without a full understanding of their negative impacts. The purpose of this thesis is to anticipate how bioenhancement will negatively impact autonomy and suggest strategies that mitigate such harm.

Some scholars have controversially argued that bioenhancement should be made compulsory, while others have responded by saying that doing so would grossly violate people’s autonomy. But I highlight that even the voluntary use of bioenhancement poses a threat to autonomy. Just as voluntarily drinking alcohol can undermine our judgement and decisionmaking, so too can voluntarily bioenhancing ourselves with other drugs or technology.

This thesis analyses theories of autonomy to assess the impact of bioenhancement on autonomy. I analyse how autonomy is impacted differently depending on whether bioenhancement targets human cognition, emotions or behaviour.

Nudge theory proposes that decision-making can be influenced by exploiting a contemporary understanding of human psychology and behaviour to guide individuals toward specific choices, without undermining their autonomy. I examine the relationship between nudge theory and autonomy. I argue that designing bioenhancements as “bionudges” can mitigate the risk of undermining human autonomy and instead promote it.