Since Simon has begun making real money, his wedding is held in a fancy hotel. Before the wedding, he tells Augie that he wants him to marry Lucy Magnus; to "not dissolve in a bewilderment of choices but to make myself hard, like himself, and learn how to stay with the necessary, undistracted by the trimmings." Five Properties and Cissy Flexner arrive, but promptly leave when they discover that they have been placed at a table set behind a pillar. Lucy is clearly interested in Augie, and begins calling him her "husband".
As Augie's relationship with Lucy progresses, Mimi Villars tells him that she is pregnant with Frazer's child. She refuses to tell Frazer, however, and plans to get an abortion. This prompts Augie to contemplate his own beginnings: "It couldn't have been an accident. On my mother's side at least I can be sure there was love in it" (254). Mimi counters this with: "Is it love that saves it from being an accident?" The question is left unanswered, and Augie defers to Mimi's decision. He takes her to an abortion doctor on the South Side, and Mimi receives a painful injection that is intended to cause contractions. The injection, however, fails to work, and an infuriated Mimi seeks other measures for terminating her pregnancy. In the meantime, Kayo Obermark, a melancholy and brilliant student who lives in the room between Augie and Mimi, notices that something is amiss. He guesses what is happening, and tells Augie: "Everyone has bitterness in his chosen thing...God had to have bitterness in his chosen thing if he was really going to be man's God, a god who was human." Mimi undergoes an operation to abort her pregnancy. When Augie expresses his concern, Simon becomes suspicious that is Augie sleeping with her.
Unfortunately, Augie runs into Kelly Weintraub at the abortion doctor's office. Kelly, who is related to the Magnuses, spreads the news that Augie is helping another woman get an abortion. Mimi begins hemorrhaging severely, and even though Augie attempts to keep his date with Lucy, he ends up driving Mimi to the hospital. Simon is infuriated when he hears the rumors, and calls Augie to berate him. The emergency room doctor refuses to treat Mimi, so Augie drives her to a clinic with Kayo and Padilla. After she is admitted, Augie rushes over to Lucy's house, only to find a very displeased Uncle Charlie. It is clear that the budding relationship between Augie and Lucy is finished.
Life returns to normal. Mimi's health improves, and she breaks up with Frazer, and Kayo Obermark begins taking Augie with him to lectures. Augie tells the reader: "I wasn't convinced about the stony solemnity, that you couldn't get into the higher branches of thought without it or had to sit down inside these old-world-imitated walls. I felt they were too idolatrous and monumental" (286). Mimi introduces Augie to her friend Grammick, a law student and CIO union organizer, and he embarks upon yet another occupation. As a union organizer, Augie begins dating Sophie Geratis, a Greek chambermaid at a luxury hotel. She is already engaged to another man, but the two tumble into a relationship regardless. One night, when Augie is in his room making love to Sophie, he hears a knock on the door. He immediately recognizes the voice on the other side as belonging to Thea Fenchel, and - much to Sophie's disappointment - rushes to answer it.
Augie's union activities become problematic, and Grammick tells him to lie low. Augie goes to stay with Thea at her hotel. The two fall in love, and Thea asks him to go with her to Mexico, where she plans to procure a divorce from her husband, a very wealthy man named Smitty. Augie, believing himself to be in love, agrees to go: "I was threaded to her as if through the skin." Thea reveals her money-making scheme to train an eagle to hunt giant lizards, and Augie learns that Thea has wealthy relations, but that she herself is not particularly rich. He also senses the extremity of her personality, particularly in the way she plays the piano: "loose on the keys, chords overreached and elements spilled." Still, however, Augie feels certain that he loves her. He sees the eagle as Thea's "chosen thing", and, ignoring the warnings of his friends, drives a station wagon down to Texas with Thea, where Thea purchases a bird. She seems to have an innate understanding of how to tame the bird, and they continue down into Mexico. In Mexico, the eagle commands extraordinary respect, and Augie christens him Caligula. Thea teaches him to fly after a lure and to descend on her fist, and Augie gradually becomes thrilled by the remarkable sight of Thea holding her eagle.
Augie's desire to help Mimi Villars is largely what inspires the drama surrounding her abortion and the crisis with the Magnus family. Simply for caring about the girl and attempting to ensure that she receives proper medical care, Augie destroys his relationship with Lucy Magnus. Though his real feelings for Lucy are never explicitly revealed, the reader can deduce that Simon has orchestrated much of the relationship in the hopes that Augie will follow in his footsteps and become a part of the Magnus family: "The world hasn't set too tight yet. There's room, if you find the openings to it." While Augie is not by any means a Machiavellian figure, he tells the reader: "I had a desire to go along with him out of the love I felt for him and enthusiasm for his outlook. In which I didn't fundamentally believe."
The issue that ultimately splinters Augie's relationship with the Magnus family is that he doesn't have the same personality as Simon; he is not, as Uncle Charlie quickly deduces, a Machiavellian. Additionally, while Augie does not seem to mind taking Lucy out on dates, he never expresses any real desire to become her lifelong companion. In fact, he seems far more interested in Mimi. When Mimi Villars tells Augie that she is pregnant, the events unfold as though Augie is her lover and the father of her unborn child. Again, he passively allows others to make this assumption (perhaps as a form of wish fulfillment), and this characteristic passivity leads to disaster. The mistaken belief that Augie is the father echoes Thea and Esther Fenchels' early assumption that Augie was Mrs. Renling's gigolo.
In the end, one cannot be too judgmental about Augie's inability to commit to Lucy, because he abandons her out of a sincere desire to help a friend in need. Mimi's pregnancy and decision to abort her baby inspire Augie to contemplate his own origins, and the memorable conversation between Mimi and Augie about the "accidental" nature of the pregnancy and Augie's opinion that "love" transforms "accident" - that Augie's mother's "love" had transformed a series of accidents into a family - reveal Augie's genuine belief in love. He respects Mimi's choice, but holds on to his personal outlook on life. Mimi refuses to let "accidents" dominate her life, while Augie places all of his faith in love's transformative power.
The urgency of Mimi's infection, the rumor of Augie's paternity, and Lucy's New Year's Eve formal all converge into a swell of compelling narrative drama. Augie's choice of Mimi over Lucy echoes Kayo Obermark's words: there is bitterness in one's chosen thing. In the end, Augie regrets how things ended up with Lucy. Augie's "choice" also closes off the possibility that he might follow in Simon's footsteps, as Simon cuts Augie off altogether in retaliation for the mess he has made of his plans. Augie returns to his pseudo-student life, and Mimi finds a job for him as repayment for his help. Ironically, Augie's actions do not make Mimi any more inclined to become his lover; instead, she begins to date Arthur, emphasizing the fact that Frazer and Arthur are on a stratum far out of Augie's reach.
As a union organizer, Augie never quite expresses the strong sense of political commitment that inspires "meek" men such as Grammick to become eloquent speakers and effective leaders. When he visits Einhorn, the older man reveals his general cynicism about political ideals - a cynicism that Augie apparently does not enjoy hearing about. At the same time, however, Augie does very little to convince the reader that he truly harbors communist beliefs. Forever the dilettante, Augie does well under Grammick's direction, but has no trouble leaving his job when he falls in love with Thea and employment becomes inconvenient. The fact that Augie attends to Thea in Sophie's presence also reinforces his inability to commit to people. Though he displays bravery in his willingness to act on his feelings, he fails to put forth the steady "face" that the social world wishes to see.
When Thea (meaning "goddess") reappears in Augie's life, he quickly falls in love. Thea proves to be an extreme personality: passionate, powerful, and intent on adopting Augie just like the rest of the Machiavellian characters in the story. She dresses him in the clothes of a sportsman and aims to recreate him in her own "huntress" image, echoing Mrs. Renling's desire to make him "perfect". Augie, again displaying ambivalence about his true identity, allows Thea to define his identity for him. He welcomes the chance to go to Mexico, despite his friends' warnings. This escapist proclivity echoes his decision to follow Joe Gorman out east, hinting at the inevitably disastrous outcome.
Thea proves to be a decisively Machiavellian character. Like Augie, she acts in accordance with her feelings, but like Simon, she is honest about her ambitions, and has a clear - albeit bizarre - sense of commitment. Augie respects her "chosen thing": training the eagle. This endeavor symbolizes the relationship between nature and humanity: the Machiavellians in the narrative seek to dominate "nature" (usually represented by Augie). Thea hopes to train the eagle (and, it is implied, Augie) to hunt for a mark without flinching, just as she hunted Augie by hiring detectives. The fact that Augie labels this endeavor her "chosen thing" foreshadows the bitterness Thea will ultimately come to feel.