Some time passes; when we rejoin Isabel's life, she is waiting anxiously for Caspar Goodwood to arrive, dreading the scene she believes will ensue. Goodwood enters and tells Isabel that he has received her letter informing him of her decision to marry Gilbert Osmond. Isabel says that she has told no one but him and Madame Merle. Goodwood is obviously hurt, but he is his usual aggressive self: he presses Isabel to tell him about Osmond's attitudes, opinions, and personality, particularly his feeling for America. Isabel angrily insists that Osmond does nothing, thinks nothing, and has no opinions. Brokenly confessing his selfishness, Goodwood tells Isabel that he would rather she never marry than to marry another man. He storms away, and Isabel begins to cry.
After a short time, Isabel collects herself; she goes to tell Mrs. Touchett about her engagement. Mrs. Touchett is furious, realizing that Merle has tricked her, having convinced her not to interfere in Isabel and Gilbert's romance by promising to end it herself. Mrs. Touchett implies that Merle and Osmond have tricked her into the engagement, and in any case she cannot understand why Isabel would be interested in a man as insubstantial as Gilbert Osmond. Isabel says that if he has no substance, he cannot hurt her. Ralph arrives in Florence two days later, looking grim and ill. To Isabel's surprise, he says nothing about the engagement; she assumes that he disapproves, and Mrs. Touchett tells her as much, but she chalks up his disapproval to their family relationship—she thinks that all cousins must disapprove of one another's marriages. While coming to terms with her family's disapproval, Isabel continues to meet with Osmond every day.
After three days, Ralph encounters Isabel in the garden at the Palazzo, and tells her that he is ready to speak to her about her engagement. He says that he worries that she is putting herself into a cage, forfeiting her chance to travel and to observe a wide array of life and allowing herself to be taken adavantage of by a narrow, dry, selfish man; he says that Osmond's only quality is his aesthetic taste, and Isabel deserves to do more in her life than protect the aesthetic taste of such an insignificant man.
Isabel defends Osmond, implying that he has inner qualities that only she appreciates. She says that she is eternally grateful to Mr. Touchett for giving her the means to marry a man such as Osmond, who has no money and little social position. Ralph says that he worries that her love of Osmond is based on an illusion that she has convinced herself to believe. Ralph also confesses to Isabel that he loves her, but he says he has no hope of ever acting on his love or having it returned.
Isabel does not tell Osmond that her family disapproves of the engagement, but he guesses it; one day he tells Isabel that he has never worried about money, and he hopes her family does not believe that he would marry her for her money. Inwardly, Osmond is very pleased with Isabel; he thinks that she reflects all his ideas like a perfect silver dish. Pansy is also pleased that Isabel will be her stepmother. When she encounters Pansy at a party thrown by the Countess Gemini, she has a brief sense of fear, thinking that she may one day have to protect Pansy from her father. But she puts the thought out of her head without fully understanding it. At the party, the Countess also tells Isabel that she is pleased with the engagement. She asks Pansy to leave them for a time, as she has some advice for Isabel about marriage. Isabel asks Pansy to stay, saying that she does not wish to hear anything that is unfit for Pansy.
Three years pass. A young man named Edward Rosier, who was friendly with Isabel and Madame Merle in Paris, calls on Madame Merle in Rome. He asks her for help with his suit to marry Pansy; he and Pansy love one another, but he suspects that Pansy's father will oppose their marriage. He wants to speak to Isabel about it, but Madame Merle warns him that Isabel has no standing in her marriage—she is barely treated as part of the family. Instead, she and Gilbert disagree about everything and seem to despise one another. She also reveals that Isabel gave birth to a son two years ago, but he died when he was only six months old.
Rosier leaves Madame Merle's house chastising himself for bringing his problem to her—he realizes that she has no intention of helping him convince Gilbert Osmond that he should marry Pansy. Every Thursday night, Isabel holds a social gathering at her house in Rome, the Palazzo Roccanero. Rosier attends, thinking that the building is a prison in which Pansy is an inmate. Though he is impressed with the opulent collection of art and furniture the Osmonds have acquired, Rosier tells himself that he has more important things to do than look at art: he must find a way to convince Pansy's father to allow him to marry her.
This section begins with the news of Isabel's engagement to Osmond, an event that James chooses not to narrate. It ends after Isabel has been married for three years—years James also skips over, after skipping over the wedding and the birth and death of Isabel's son.
James's elliptical technique is in full swing throughout this section; almost all of the scenes that are narrated are conversations that are peripheral to Isabel's life—and even they are almost always shown through the perspective of someone else. The important events are left out altogether, and only implied by the peripheral conversations. The reader loses touch with Isabel almost completely, and in this way James creates the sense that, by giving herself to Osmond, Isabel has been lost.
The question arises: if James leaves so much out, what can we ascertain from that which he leaves in? First, in Isabel's conversation with Mrs. Touchett, we receive a brief glimpse of what Isabel sees in Gilbert Osmond. We have already seen that she has superimposed her own romantic idea of a refined, artistic genius over Osmond's arrogance and selflishness; now, she tells Mrs. Touchett something of her feeling for the real Osmond. Mrs. Touchett says that Osmond is a "nothing," that he has no qualities; Isabel replies that if he is so insubstantial, he cannot hurt her.
In the conflict between independence and social convention as it applies to Isabel's romantic life, it seems that the idea of "substance" in a man is what threatens Isabel's notion of her own independence. Though she is drawn to Caspar Goodwood, he is such a powerful physical presence that he seems to overwhelm Isabel's own independence. Osmond is in many ways Goodwood's opposite, a man with no presence—he is simply a graceful nothing in Isabel's mind. Where Goodwood is forceful, Osmond is charming; where Goodwood is a symbol of American capability, Osmond is a symbol of European decadence. Ironically, of course, as Henrietta perceives, it is Osmond and not Goodwood who represents the real threat to Isabel's freedom.
Ralph's conversation with Isabel in the garden is a watershed moment in the novel. To this point, Ralph has been an unfailing source of strength for Isabel; he has provided her with support, sympathy, and understanding since their first meeting at Gardencourt, and he has consistently advocated the very independence that Isabel claims to want for herself. In the last several chapters, he refused to believe that Isabel would fall in love with Osmond, claiming that she was far too intelligent not to see the threat that he would represent.
Now, however, Isabel has announced her engagement to Osmond, and Ralph can no longer deny that his beloved cousin is in jeopardy of throwing her independence away. He tells her how he feels, and she becomes self-righteous and emphatic, insisting that her imaginary picture of Osmond is the real thing: that he is kind and devoted to higher things. Ralph is far too good a judge of character to be fooled by Isabel's naïve portrayal of her fiancé, and he tells her that he worries she is fooling herself. She angrily rejects his advice, and from this moment until the end of the novel, Ralph and Isabel's relationship becomes distant and strained.
Though nothing of special narrative importance happens in this moment, it is still extremely important in the novel. The issues are placed very clearly before Isabel: she is shown that she can either rely on herself and choose independence or that she can rely on Osmond and give up her independence in favor of safety and social convention. Rather than exercising her intelligence and choosing to remain independent, Isabel follows her immature, romantic imagination and chooses to sacrifice her independence for safety and social convention. Nothing will be the same for Isabel again.
After the three years of Isabel's marriage, we are taken into a new subplot, involving the drab art collector Edward Rosier's desire to marry the placid and submissive Pansy. James utilizes this subplot to take us gradually back into Isabel's life, allowing us to feel out the changes that have befallen her since her marriage to Osmond. Rosier's conversation with Madame Merle lets us slowly back into the situation: Merle is still present in Osmond's life and apparently still quite important in it; Merle is still manipulative and still tries to control social situations.
Isabel, we learn, has fallen into a miserable sham of a marriage, as the reader might have predicted; Merle says that she is barely given any status in her marriage, treated as though she is barely even part of the family. Osmond married Isabel for two reasons: her money, and because she is an object he can add to his collection, drawing admiration and envy from his acquaintances and acting as a hostess for his parties. Beyond these roles he has no interest in her. The reader (advised by Ralph) has long realized that this would be the case; Isabel has just learned it and has learned it the hard way.