Examining the corpse, Severinus confirms that Berengar died of drowning. He also suggests that Berengar and Venantius might have touched the same poisonous substance, since both their fingers are black and Berengar’s tongue is black as well. Berengar might have been poisoned, gotten into the bath to try to calm his spirits, fallen unconscious, and then died. Severinus mentions that years ago he had a dangerous poison in the infirmary that causes fatigue, paralysis, and then death. Someone had broken into the infirmary, and when he had cleaned up the wreckage, he found the bottle missing. Since this theft took place years ago, William thinks it suggests “a malignant mind brooding for a long time in darkness over a murderous plan.” Someone stole the poison years ago, and has been waiting for some time to use it.
Unlike Venantius, Berengar seems to have actually died of drowning. However, he might have ingested the same poison as Venantius, since they both share the telltale signs of blackened fingers and tongues. Possibly he was poisoned and then fell unconscious as a result. Severinus mentions that he did once have such a poison in his infirmary, but it was stolen years ago. This suggests that whoever is behind the crimes may have been plotting the murders for years—a disturbing thought that suggests a “malignant mind.”
Malachi comes in to speak with Severinus, but quickly leaves when he sees William and Adso there. Salvatore accounts for the presence of the girl in the kitchen, confirming William’s theory that he procures women from the village for Remigio, who offers them food in exchange for sex. William then confronts Remigio, who admits to this behavior as well as admitting that he used to be a follower of Dolcino. He confesses that the night that Venantius died, he came into the kitchen for his assignation with one of the village girls and found the corpse, with no sign of a struggle and a broken cup of water on the ground. He decided to leave the corpse where it was, since to raise the alarm would have incriminated him. William suggests that Malachi might have moved the corpse, but Remigio denies it, saying that he owes Malachi a debt. Meanwhile, Adso longs to see the girl again.
Malachi’s presence in the kitchen, along with Remigio’s statement that he owes Malachi a debt, suggests that there is some connection or understanding between them. Meanwhile, Remigio confirms William’s theory that he gives food to the peasant girls in exchange for sex, demonstrating the extent of the poverty and hunger in the village adjoining the wealthy abbey. The church hypocritically keeps vast stores of wealth and food and employs many servants, while in the village below people are so desperate that young women have turned to prostitution.
Severinus finds the stolen glasses in the dead Berengar’s pocket and returns them to William, just as Nicholas arrives with his new lenses. With his two pairs of glasses, William deciphers the Greek portion of Venantius’s manuscript, but the words make no sense and seem “the ravings of a madman.” However, William suggests that the notes have meaning beyond the letter and must refer to some other book. William says that books “always speak of other books,” and so a book can never be truly hidden, since traces of it will remain in other texts. However, the library’s attempt to suppress some books has “delayed” the appearance of the truth.
Although the library’s attempt to and hide the forbidden book has “delayed” the appearance of the truth, the secret knowledge will come out eventually. This suggests that all attempts to suppress knowledge are ultimately futile. This is because books are “intertextual”—they reference other books. A book can’t be silenced as long as its voice still speaks in other texts, like Venantius’s notes.
William goes back to his room to think while Adso goes hunting for truffles, and reflects on the oddness of the way the word “truffle” sounds like the German word for the devil. The Franciscan delegation and the Pope’s envoys begin to arrive. Adso joins a conference between William, Michael, Ubertino, and Jerome of Kaffa, a foolish bishop who hates the Pope. They accuse the Pope of heresy, since he wants to declare that the righteous will not enjoy heaven until after the Last Judgment. They reflect gloomily that the meeting with the Pope’s envoys will probably lead to nothing.
Adso’s reflections on the word “truffle” suggest that the same words can have different meanings to different people. For Adso, a truffle grows in the countryside, but to the German lord it means “der Teufel”—the devil. This is a major issue in Eco’s field of semiotics (the study of language and meaning) as well as in William and Adso’s attempts to interpret the evidence at play in the mystery of the murders.
William has a tense interaction with Bernard, whose path he clearly has crossed before. Bernard thinks William was lax in prosecuting heretics. He wastes no time in opening his own investigation into the murders, focusing on peasants rather than the monks. Adso and William talk with Alinardo, who continues to suggest that the pattern of the murders is following the Apocalypse of St. John. He also complains that he has been passed over and should have been made librarian, instead of the foreigners. Salvatore tells Adso that he plans to cast a spell to make the village girls fall in love with him: he will kill a black cat, dig out its eyes, place the eyes in two eggs of a black hen, and get a girl to spit on them.
Bernard and William have stark differences in the way they see the world. Bernard is a notoriously harsh judge, while William quit his job because he didn’t feel comfortable sentencing people to death based only on his judgments. Meanwhile, Alinardo’s comments continue to suggest that there is an underlying pattern to the murders—that they aren’t random acts of violence, but rather are proceeding according to some grand plan. This encourages William and Adso to come up with further theories to try to understand that overarching pattern.
William and Adso visit the labyrinth again and discover more about its layout. The group of rooms whose labels spell out the word “Hibernia” contains books from Ireland, “Yspania” contains books from Spain, “Gallia” contains books from France, and “Roma” contains books in classical Latin. The organization of the library is a map of the world: “Hibernia,” for example, is the western tower.
By breaking the code of the words of the Apocalypse on the scrolls, William and Adso finally understand how the library is organized. This emphasizes that it is often necessary to have broader context in order to understand the meaning of signs. The words seemed like random phrases from the Apocalypse of John until William and Adso realized that there was a pattern connecting them—a code spelled out by the first letter of each word.
William and Adso find “Leones,” the south tower, which contains books from Africa and the Middle East. Although William says that these books contain “monsters and falsehoods,” he also believes that they contain “works of science from which Christians have much to learn.” He explains that there can be something to learn even from a falsehood: the unicorn is an imaginary creature, but it “embodies a moral truth,” the idea of chastity as a noble virtue.
William’s comment demonstrates his open-mindedness and lack of judgment. Although the founders of the library judged certain books as “false” because they were written by African and Middle Eastern authors, William suggests that Christians “have much to learn” from these works.
William and Adso realize that the “Leones” tower is missing its central heptagonal room—and yet, logically, the room must exist, so William hypothesizes that it has been walled up. This room must be the “finis Africae”—the end of Africa. Venantius’s notes referred to the “idolum,” which William realizes means the image in the mirror. The finis Africae is concealed behind the mirror that reflects distorted images. Despite this discovery, however, William and Adso can find no way into the secret room. They proceed through the rest of the library, reading books along the way: Adso reads several learned treatises on the malady of love, coming to the conclusion that he will be saved if he never sees the object of his affection again.
William and Adso finally discover the secret of the designation “finis Africae” in the library catalogue. However, they are no closer to entering the room, which is concealed behind the vision-distorting mirror. This suggests that the founders of the library did not want people to be able to enter this room and have access to the forbidden knowledge contained within its walls. The library has preserved certain books, even dangerous ones, but has locked them away so that no one can lay eyes on them.
When William and Adso return from the library, however, they do see the girl from the village. Bernard has arrested her and Salvatore, since Salvatore had been using a ritual involving a black cat to try to cast a love spell on her. Bernard reminds William that he has seen such devilish rituals before, but William stays silent—out of cowardice, Adso believes. The girl is accused of witchcraft and sentenced to be burned at the stake, and because no one speaks her local dialect to translate for her, she is not able to defend herself. Adso tries to help her, but William prevents it, telling him that there is nothing he can do. Ubertino tells Adso that the girl’s provocation of his desire proves that she is a witch.
The girl from the village is a victim of Bernard’s harsh judgments and zeal for punishment. He does not care that she cannot defend herself because no one speaks her language. Instead, he is quick to punish what he sees as “heresy,” witchcraft, and challenges to religious authority, using Salvatore and the girl as scapegoats. Ubertino also expresses these superstitious and unfounded judgments when he tells Adso that the girl’s beauty must mean she is a witch.