Traces the lineage of the American visionary tradition through 3 cent. as sustained in a continuous "shadow culture" outside the mainstream. Discusses America's first Great Awakening (GA), led by Jonathan Edwards and Conrad Beissel. Illustrates the role of altered consciousness in early American religious life. Revisits the luminaries of the second GA, painting fresh portraits of Emerson, Thoreau, and Margaret Fuller, and the shadow culture's interest in phrenology and homeopathy. Today's GA is also rooted in a shadow culture -- the counterculture of the 1960s. Focuses on spiritual practitioners who have found fulfillment outside of mainstream institutions and their own cultural heritage -- in Hindu yoga, Zen meditation, Muslim Sufi masters, and Buddhism.