Though Blake was influenced by his grand and mystical cosmic conception, Swedenborg's conventional moral strictures and his Manichaean view of good and evil led Blake to express a deliberately depolarized and unified vision of the cosmos in which the material world and physical desire are equally part of the divine order; hence, a marriage of heaven and hell. The book is written in prose, except for the opening "Argument" and the "Song of Liberty". The book describes the poet's visit to Hell, a device adopted by Blake from Dante's Divine Comedy and Milton's Paradise Lost.