Lily, having spent the night at the Bellomont, is asked to join Mrs. Trenor in the morning to help her write some correspondence. Although Lily would rather not, she remembers that she is dependent on Mrs. Trenor for social standing and does not want to upset her. The two gossip extensively while they write dinner cards, providing the reader with information about the politics and current events of the social group. In particular, we learn that Gwen Van Osburgh was not entertained by the party, Alice Wetherall and her husband were invited by mistake, and that Maria Van Osburgh was infuriated because Mrs. Trenor's party "stole" guests from a party that she herself was throwing that week, including Lady Cressida Raith, an enormous bore and hypocrite whom Mrs. Trenor now dislikes. Bertha Dorset is also upset with Mrs. Trenor because she came to the party under the assumption that Selden would be present, and when he failed to attend, Bertha suspected that Mrs. Trenor had lied to her and not even invited Selden.
Lily confesses to Mrs. Trenor that she is interested in a marriage to Percy Gryce, largely because of his finances and good societal standing. We learn later that Lily believes that she will almost inevitably marry Gryce, thinking she has him under her control.
Later, Selden joins the party at the Bellomont, and after Lily goes to the library and finds Selden and Mrs. Dorset alone together, she suspects that Selden has really come to the Bellomont just to see Mrs. Dorset. Selden later confesses that he came solely because he wanted to see Lily. In the presence of Selden, Lily begins to examine her own social world and wishes that like Selden, she were detached from it.
The end of Chapter Five and all of Chapter Six focus on a walk that Lily and Selden take together after church ends on Sunday. They discuss a number of details about their lives and also share some of their philosophies on money, success and society. Selden says that he believes Lily is interested in Gryce, who left the Bellomont after Lily canceled their plans to go on a walk together (so that she could secretly spend time with Selden instead). We learn also that Lily has once before been in love several years before the action of the novel to a man named Herbert Melson, who ended up marrying the oldest Van Osburgh daughter.
Lily confesses to Selden that she knows her quest for better social status will not necessarily bring her true happiness. However, she and Selden agree that they will not marry one another. However, just as they are drifting towards what could be a confession of love for one another, they hear a car start its engine nearby, which reminds Lily that she must return to the Bellomont before people question her whereabouts.
The gossiping between Mrs. Trenor and Lily in Chapter Four provides the reader with some clues about the role of family in the society. Many of the female characters have been through at least one divorce; Mrs. Trenor mentions that between the Winton and Farley families there are "five divorces and six sets of children." This is Wharton's method of foreshadowing that The House of Mirth will not follow the conventional form of the novel of manners (see "The Novel of Manners" section), which normally does not feature divorces or broken homes. Because not all characters meet with happy endings, we begin to suspect that despite a relatively promising future, Lily also will fail in her attempts at securing happiness. The fact that Lily already failed once in love when she fell for Herbert Melson is another clue that Lily does not and will not meet with success in love.
The circle of people at the tea table in the last few paragraphs of Chapter Four provides a good example of Wharton's symbolism. The literal circle formed by the women at the tea table figuratively represents the social circle Lily is so eager to join. She does not sit with the ladies (although she believes she could), thinking instead about her impending marriage to Gryce, which she believes is inevitable. She believes that after marrying Gryce, she will secure income and social status, her two most desired commodities. Ironically, she delays joining the circle of tea drinkers, thinking she will have many other chances to do so. When her hopes are shattered at the end of Chapter Eight with the announcement of Gryce's engagement to Evie Van Osburgh, Wharton suggests that the New York social world is so exclusive and demanding that one can never be assured a place in its circle.
Indeed, one of the themes in the novel is that the social situation of an unmarried woman in New York at this time is very fragile and variable. In the course of three days at the Bellomont, Lily goes from a fear of her social and economical insecurity to an arrogance that comes with the false assumption that she can marry Gryce. This changes entirely the way she views her prospects: "Life was not the mockery she had thought it three days ago"; it is almost absurd that someone's outlook on life could change so drastically and suddenly, and so we must question the merit of Lily's emphasis on the importance of fitting in. We see that Lily's perception of herself is based on her social status, which is why she is so committed to becoming accepted even if it means marrying someone she does not love. The narrator even suggests that Lily "was inwardly as malleable as wax." The premise is that as long as Lily remains unmarried, her social position will fluctuate wildly, depending on her current financial status.
Overall, this section emphasizes Lily's indecisive nature. At dinner, Lily's comparison between Gryce and Selden reveals that she really loves Selden more than Gryce. She also sees the Selden is detached from the elite social world; he is described as an "outside observer" looking on. We begin to understand that Lily cannot and will not marry Selden, even though he is the better man, because he does not have enough money or connections. The great irony of the novel is that Selden is the only man whom Lily really loves and respects. At the end of Chapter Six, Lily and Selden come very close to confessing to one another their feelings, which are clear by this point. When they hear a car engine—a symbol of the society they have left—Lily is pulled away from confessing her true feelings because she is so determined to be an established member of society.
One should notice in this section Wharton's use of nature to convey the emotions felt by her characters. In Chapters Five and Six, the weather is described as "perfect," and Lily is even able to sense an appropriate connection between the nice weather and the pleasant walk she is to have with Selden. Wharton makes use of this throughout the novel; it will come up again in several scenes to give the reader a clue to the nature of the events which will follow. For instance, at the end of the novel, as Lily sets out to find Selden, the gray sky and pouring rain reflects her downtrodden, hopeless mood. The next day, the beautiful sunshine and warm air reflect Selden's joy as he sets out to propose to Lily.