Robert Torrance's wide-ranging, innovative study argues that the spiritual quest is rooted in our biological, psychological, linguistic, and social nature. The quest is not, as most have believed, a rare mystical experience, but a frequent expression of our most basic human impulses. Shaman and scientist, medium and poet, prophet and philosopher, all venture forth in quest of visionary truths to transform and renew the world.

Yet Torrance is not trying to reduce the quest to an "archetype" or "monomyth." Instead, he presents the full diversity of the quest in the myths and religious...