Necessity Over Time

Abstract This article explores how the necessity condition for permissible self-defense operates over time. It addresses two core questions. First: when, leading up to an attack, does the necessity condition begin to apply? Second: if it applies before an attack, what are the implications of disregarding it? I argue that if aggressors are fully culpable, the condition applies only at the moment of attack. For less culpable aggressors, however, it can require that defenders act earlier to avoid or reduce future harm. However, failing to comply with these earlier demands does not automatically render all subsequent defensive harming impermissible. It only makes justifying it more difficult. Finally, I discuss some implications of my views for other-defense and third-party intervention.