As a religion concerned with eternal salvation, Zen is based on and grew out of a Buddhist worldview very different from the currently prevalent scientific materialism. Indeed, says Taigen Dan Leighton, Zen cannot be fully understood outside of a worldview that sees reality itself as a vital, ephemeral agent of awareness and healing. In this book, Leighton explicates that worldview through the writings of the Zen master Eihei Dõgen (1200-1253), considered the founder of the Japanese Soto Zen tradition, which is now spreading in many places in the West. Broader awareness of Dõgen's worldview and its implications, says Leighton, is helpful for a modern understanding of Zen and Mahayana praxis, and is relevant to contemporary environmental and ethical concerns.