Vautrin Being Drugged
In order to confirm Vautrin's identity as a criminal, Mlle. Michonneau drugs his coffee so that he will fall unconscious. This event is an example of situational irony because the occurence of a devious criminal mastermind being tricked by someone else represents a contrast with audience expectations. Throughout the novel, Vautrin has been positioned as a crafty schemer who notices everything and knows how to manipulate others. In fact, he has just drugged other people himself, when he incapacitates Rastignac and Goriot to prevent them from interfering with his plan to have Victorine's brother killed. Readers expect to see Vautrin being the mastermind behind plots, not falling victim to them. Additional situational irony is created because Mlle. Michonneau seems frail and helpless, and unlikely to be able to successfully take down someone who is constantly on his guard.
Madamoiselle Michonneau Being Evicted
After Vautrin is arrested, the residents of the boardinghouse band together and demand that Mlle. Michonneau be evicted. Although they know that Vautrin is a criminal, they are angry that she lied and betrayed him. This reaction from the other boarders is an example of situational irony because readers might reasonably expect that she would be rewarded or treated with respect. Mlle. Michonneau has been brave and shrewd, and has contributed to bringing a known criminal to justice. Ironically, the boarders are more angry with her for lying to Vautrin than they are with Vautrin for deceiving them and lying about his identity. This reaction shows that the boarders operate with a close-knit sense of loyalty and expectation that they will guard one another's secrets.
Rastignac Referring to "Pere Goriot"
The first time Rastignac visits Anastasie and her husband, he casually refers to Goriot as "Pere," an informal and somewhat disrespectful term. This occurence is an example of dramatic irony because Rastignac understands his situation in one way, when the reality of that situation is quite different. Rastignac thinks he will impress the wealthy and aristocratic couple by being a bit snobby when he refers to someone from a lower social position. Because he is anxious to demarcate his own social status, he also think he can signal his own class position by referring dismissively to an old man. However, the reality of the situation is that by insulting Anastasie's father, he uncomfortably evokes her own class origins and offends both her and her husband. The reality of what he is doing by talking disrespectfully about Goriot is actually the exact opposite of the effect he thinks he is having.
Madame de Beauseant as Mentor
Early in the novel, Rastignac makes Madame de Beauseant a kind of mentor figure because he knows he needs someone who is more experienced to help him. However, this choice ends up being an example of dramatic irony. Rastignac understands Madame de Beauseant to be an appropriate mentor because she seems to have lots of experience as a prominent society figure, but the reality is that Madame de Beauseant ends up being defeated by society herself. Her love for the Marquis d'Ajuda makes her vulnerable and blind to the reality that he is betraying her with another woman. Even though she tells Rastignac to be cold, calculating, and ruthless, Madame de Beauseant is unable to follow her own advice. She becomes the subject of humiliation because everyone in society knows about the betrayal before she does. Ironically, even though Madame de Beauseant is positioned as a wise mentor figure, she is actually not cunning or cold enough to succeed in the heartless world of Parisian society.
