 It seems undeniable that the boundary between life and death is not perfectly   sharp.[4]   The specification of any standard will require some arbitrary line-drawing. Operationalizing the whole-brain standard requires a decision about which brain functions are too trivial to count and need not be tested for. Making a traditional standard clinically useful requires a cut-off point of some number of minutes without heartbeat or respiration for the loss of functioning to count as irreversible. A higher-brain approach needs criteria for determining what sorts of brain damage constitute irreversible loss of the capacity for consciousness and which count as reversible. Yet, while some arbitrariness is inevitable, and highlights a blurred boundary, the blurring in each instance concerns very specific criteria and clinical tests for determining that a standard has been met, not the standard itself. None of the blurred boundaries just considered is inconsistent with the claim that some standard is uniquely correct. Moreover, if essentialism regarding human persons is true—that is, if we human persons have an essence locating us in our most basic kind (e.g., animal, minded being)—this would strengthen the case for a uniquely correct standard by suggesting a foundation for one.