Bruno and Buffalmacco’s prank on Master Simone da Villa turns a physician’s eager curiosity into a grotesque public humiliation, then uses his fear of exposure to keep him compliant. In the ninth story of the Eighth Day, an invented company of nocturnal revelers promises extravagant pleasures; a horned beast, actually Buffalmacco in disguise, delivers the credulous physician not to a splendid feast but to a pit of filth. The prank’s second act is as important as the first: the painters persuade Master Simone that his own frightened invocation of God has put them in danger, and his embarrassment makes him treat them with still greater honor.

The story’s target and its promise

The tale is told by Lauretta as the ninth story of the Eighth Day, after the company has been discussing the shared wives and the deception practiced by the two Sienese men. Lauretta presents Master Simone as someone who seeks a trick for himself: Bruno and Buffalmacco, she argues, are not blameworthy for deceiving a man who goes looking for the supposed secret. Her framing makes the physician’s self-deception part of the joke. He wants access to a private world of pleasure and distinction, and his wish to believe the story leaves him vulnerable to the very men whose company he admires.

Master Simone, a physician born and educated at Bologna, has become friendly with Bruno. The two painters are poor, but appear to him to live merrily. After inviting Bruno to dinner several times, Master Simone decides their familiarity entitles him to ask how they manage it. Bruno pretends to disclose a secret: he and Buffalmacco, he says, do not steal, but go a-roving and thereby obtain whatever they desire. Master Simone takes the claim literally. His curiosity becomes urgent, and Bruno turns the physician’s question into an opportunity to invent an entire system of rewards.

The imaginary company

Bruno describes two disciples left behind by the renowned necromancer Michael Scott. These supposed magicians, he says, gathered a company of perhaps twenty-five townsmen, chosen not for rank or wealth but because they suited the founders’ habits. The members meet at least twice a month; each declares a desire, which the company fulfills that night. Bruno’s account grows more elaborate as it goes: the gatherings feature sumptuous hangings, tables fit for royalty, numerous servants, gold and silver vessels, abundant dishes, music, songs, candles, costly wines, and fine clothes that make even an unimportant member appear an emperor.

The greatest promised pleasure is sexual. Bruno claims that beautiful women, including queens from distant lands, can be brought to the company at a member’s request, and that each woman then retires to a bedchamber with the man who summoned her. He boasts that he and Buffalmacco can call for queens of France and England. The extravagant detail lends the fiction the surface of privileged knowledge, while its absurdity is tailored to Master Simone’s appetite for wonders and status. He does not question how the painters could command such a company; instead, he wants to join it.

The men tell him that he has been accepted and give him precise instructions for his first appearance. At the season of the first sleep, he must wait on a newly made tomb outside Santa Maria Novella, dressed in one of his finest gowns. A small black, horned beast will arrive, capering and whistling to frighten him. He must not call upon God or the saints, but cross his hands upon his breast and mount the beast when it becomes calm. Bruno warns that any show of fear could bring him to a place where he would stink for it. The directions transform the supposed initiation into a test of obedience, while also planting the very fear that will undo Master Simone.

The ride and the fall

Master Simone boasts that he will attend in his scarlet doctor’s gown and expects to become captain of the company. He insists that neither cold nor danger will keep him away. That evening, however, his actions betray his confidence: he makes an excuse to his wife, secretly takes out his fine gown, and goes to the tomb. Meanwhile, Buffalmacco puts on a black fur pelisse inside out and a horned mask with a devil’s face. Bruno follows to watch.

Buffalmacco capers, whistles, howls, and bellows around the piazza. Master Simone trembles so violently that he wishes he were home, but he forces himself to stay because he still wants to see the marvels promised by the painters. When the supposed beast approaches the tomb, he hesitates over whether to mount. Fear of what the beast might do if he refuses overcomes his first fear; he climbs onto Buffalmacco’s back. Although instructed to keep silent, he softly calls on God for help.

Buffalmacco moves on all fours, carrying him toward Santa Maria della Scala and then near the Nunnery of Ripole. At a dyke used by neighboring cultivators to empty privies and manure their fields, Buffalmacco seizes one of the physician’s legs and pitches him headfirst into the pit. He then snorts, snarls, and capers before running off. Bruno, who has fled because he cannot contain his laughter, meets him at Allhallows Fields. The two watch from a distance as Master Simone struggles to escape, falls back into the filth several times, and swallows some of it before finally climbing out. He is befouled from head to foot and has left his bonnet behind.

Shame turned into leverage

Master Simone returns home and knocks until admitted. His wife sees his stained condition and his scarlet gown and concludes that he has been visiting another woman. She accuses him of seeking to cut a figure with his clothes and scolds him while he washes himself through the night. The episode gives the prank an unintended domestic consequence: the physician’s attempt to pursue the imagined company leaves him facing his wife’s suspicion as well as the humiliation of the pit.

The next morning, Bruno and Buffalmacco visit with livid marks painted on their bodies. They pretend to be furious, alleging that Master Simone’s disloyalty endangered their admission to the company and that they were beaten for his conduct. When he tries to explain that he was thrown into a dyke, Buffalmacco redirects the accusation: the physician, he says, repeatedly called upon God and the saints despite the warning. Master Simone denies doing so, but the painters insist that their messenger reported his fear and trembling. They threaten, in effect, to expose him and his failure to the very society he longs to join.

The physician begs their pardon and implores them not to dishonor him. Instead of confronting them or exposing their deception, he becomes more deferential than before, entertaining them with banquets and other favors lest they publicize his shame. The trick therefore does not end when he climbs out of the pit: its final reversal is that the victims’ embarrassment becomes the deceivers’ continuing advantage.

Comic reversal and narrative effect

The story repeatedly inverts the standing Master Simone imagines for himself. He expects to arrive in a scarlet gown, be recognized as a man of gentle birth, and perhaps become captain; he ends the night without his bonnet, covered in ordure, and scolded at home. The supposed supernatural test is not a passage into elite pleasures but a staged fall into the most degrading physical place in the story. The contrast between the company’s gold vessels and splendid beds and the real dyke makes the physician’s credulity visible in bodily terms.

The prank also depends on speech as much as disguise. Bruno’s lavish account gives Master Simone a world he is eager to believe in; the instructions turn that belief into action; and the fabricated report of the messenger converts the physician’s own fear into evidence against him. Even after the beast’s identity and purpose have been revealed to the reader, Master Simone remains caught in the painters’ invented rules. Lauretta closes by treating the episode as a lesson in sense for one who has learned too little at Bologna. The comic punishment is not simply that a foolish man falls into filth, but that he continues to honor the men who put him there because their story has made his vanity, fear, and shame work against him.