However, the main challenge for these views is to impose moral limits on the permission to harm the non-liable. Why, for example, does my personal prerogative not permit me to eat a baby if necessary to avoid starvation, or lethally trample over innocent obstructors? If one may kill a non-liable person to save oneself it looks as if many innocent bystanders will be rendered legitimate targets, alongside innocent threateners. Proponents of agent-relative permissions have defended additional principles that restrict the range of non-liable persons who may be permissible harmed (Quong 2009; 2016; 2020: 80–92; Lazar 2015). But their verdicts are nonetheless revisionary in many cases.