Ghosts come from Purgatory, "the middle space of the realm of the dead." In Angels in America, the two characters who see ghosts are victims of AIDS, themselves occupying a kind of middle space. While their visions can be seen as fever-, medication-, or stress-induced, both Prior Walter and Roy Cohn are, in fact, sanctified by their proximity to death, and the liminal "space" of AIDS functions as a metaphor for Purgatory throughout the play. In this magical world, Prior Walter is a pilgrim. AIDS is not only death but a precondition for life, as Prior learns on his prophetic journey. He sees because he has AIDS; he survives because he sees; and in the end, he shares his vision with humanity.