In Canto IX of the Purgatory, the Pilgrim, overcome by fatigue toward the end of his evening in the Valley of the Princes, falls asleep (this is the first time he sleeps in the poem) on the grass where he has been sitting with Virgil and Sordello, Nino and Conrad; soon he will be dreaming. This first sleep and first dream mark the Pilgrim's passage to the Purgatory from the Antepurgatory; he will have two more dreams similarly connected with his arrival at a new, important stage in his journey, and all three dreams are prophetic. Accordingly, some scholars have chosen to treat the three dreams together; I, however, shall treat only the first. [...]