All human beings must confront their own mortality. While science and medicine have helped us to extend the natural length of a human life, they have not yet brought us a way to cheat death. Despite this, many believe that there is something more, that death is not the final end.

In this five-part series, sponsored by a generous grant from the John Templeton Foundation, we ask some fundamental questions about what it means to live a mortal life, and what an immortal life—be it biological, technological, or spiritual—might be like.

Would we want immortality, of any kind, were it possible? How would living forever change our values, relationships, and priorities? What might the eternal life of the soul actually look like? Do different cultural visions of immortality make different philosophical assumptions about the nature of the self, and what it would mean for it to persist in some form beyond the death of the body? And how does the knowledge that others will live on after we die give our earthly lives purpose and meaning?