Jonathan Glover defines death as the irreversible loss of consciousness. This, he thinks avoids a problem posed by a thought experiment: imagine a man’s heart stops and a doctor is poised to revive him fully expecting to get his heart going again. But the man’s heir plunges a knife into his chest before the doctor can do anything. Does the heir violate a corpse or take the life of an innocent human being? He violates a corpse only if death is defined by the cessation of pulmonary circulation. But that is very counterintuitive; what really matters is the irreversible loss of consciousness, something that could have been regained if the doctor had revived the patient.
Objection: suppose the heir doesn’t interfere and the doctor gets the man’s heart going again, but unfortunately the man never regains consciousness. After the doctor determines that the man’s consciousness has been irreversibly lost, the man’s heir plunges the knife into the man’s chest. Does he violate a corpse or kill an innocent human being? It seems clear that he doesn’t violate a corpse; therefore he kills an innocent human being, which means the definition of death has nothing to do with the irreversible loss of consciousness.