Robert Duncan's poetic creativity does not exist without a language of illness, nor the revelation and insight that such language generates. This ground-breaking interdisciplinary work is one of the first book-length studies of Robert Duncan's poetry, and it includes a treatment of his influences (H.D. and Freud) and those he influenced (Nathaniel Mackey and John Taggart). Through close readings of crucial poems, Peter O'Leary shows how Duncan's poetry locates a gnostic insight expressed through a language of illness in the realms of religion. Gnosticism is a doctrine of salvation by knowledge. In addition to studying Duncan's poetry and his life, O'Leary considers the psychological impact Freud's ideas of the unconscious and dream interpretation had on the poet. O'Leary continues with an analysis of Duncan's work in light of the theories of shamanism put forth by religion historian Mircea Eliade. Along the way, O'Leary undertakes detailed discussions of gnosticism, hermeticism, spiritualism, psychoanalysis, shamanism and religions of the African diaspora.