Some amoebae, to be sure, do die. Sometimes an amoeba cannot get sufficient food or oxygen or moisture to sustain its life, and that kills it. But some amoebae do not get an opportunity to die … let us consider a well-fed, healthy amoeba alone in a drop of well-oxygenated pond water. I shall call it ‘Alvin.’ Alvin, let us suppose, lives happily through Tuesday and then, precisely at the stroke of midnight, Alvin divides, producing two offspring whom I shall call ‘Amos’ and ‘Ambrose.’ On Wednesday, we find two amoebae — Amos and Ambrose — swimming happily about in our drop of pond water. But what has become of Alvin? One thing is quite clear: Alvin is not an inhabitant of our drop of pond water on Wednesday. … His life, therefore, must have come to an end. But it is equally clear that Alvin did not die.

— Jay F. Rosenberg, Thinking Clearly About Death, 1983