Encouraging Liza to realize her sad situation as a prostitute, the underground man asks her, “Do you seriously think that you’ll never grow old, that you’ll always be pretty, and that they’ll keep you on here forever and ever?” He tells her that when he arrived at the brothel he was “disgusted to be here with you,” but says that if she left he could fall in love with her. He asks why she is making a slave of herself and allowing herself “to be defiled by any drunkard.”
The underground man resumes a more malicious mode of speaking, trying to make Liza upset by emphasizing all the negative aspects of her life in the brothel. He seems to be trying to make himself feel and seem better by making her feel and seem worse.
The underground man continues to emphasize the sadness of Liza’s life, saying that none of her lovers respect her, and telling her that she will be in debt to her madam and she’ll eventually be kicked out of the brothel. He tells her, “You’ll lose everything here, everything, without exception—your health, youth, beauty, and hope.” He says she’ll wind up beaten and humiliated by “cabbies and drunken soldiers,” and tells her she’d be lucky to die quickly of consumption.
The underground man continues in his spiteful attempt to make Liza upset. He elaborately imagines her future life in detail, as if thinking of a fictional story.
The underground man says that perhaps Liza will grow sick in the brothel, and no one will care for her. Everyone will simply wait for her to die and shove her “into the filthiest corner of the cellar. And someone will bury her as they did the prostitute he saw earlier. He tells her, “There’ll be slush, filth, and wet snow in your grave,” and says that there will be no memory of her on earth.
There is no particular rational reason for why the underground man is so cruel to Liza. Perhaps on some level he is trying to help her by getting her to want to leave the brothel, but perhaps he is merely a spiteful, misanthropic person.
The underground man stops talking to Liza and says he felt like he had “turned her soul inside out and had broken her heart.” He says he could not help but speak “like a book.” He then realizes that Liza is lying on the bed in despair, crying into her pillow. He feels remorse and tells her to forgive him. He gives her his address and tells her to come see him.
The underground man cannot help but have aspects of the books he reads influence his manner of thinking and speaking “like a book.” In a somewhat startling reversal, he feel some remorse for having inflicted pain on Liza.
Before the underground man leaves, Liza shows him a love letter to her from a medical student she had met at a dance, as proof that “she too was the object of sincere honest love, and that someone exists who had spoken to her respectfully.” The underground man then leaves the brothel and walks home in the wet snow, feeling that he is aware of “the ugly truth.”
The “ugly truth” of which the underground man is aware is left ambiguous: perhaps it is the truth that Liza is alone and in a horrible situation, or that the underground man himself is, or that life itself is irrational and full of suffering.