In Book 1, Chapter 2, Amory immerses himself in his new life as a Princeton student. It is immediately clear to the reader that the school has an enormous hold on Amory, and Fitzgerald uses personification and metaphor to show how Amory conceives of the school and his place within it:
The college dreamed on—awake. He felt a nervous excitement that might have been the very throb of its slow heart. It was a stream where he was to throw a stone whose faint ripple would be vanishing almost as it left his hand. As yet he had given nothing, he had taken nothing.
In the first half of this passage, Princeton becomes a living body with a heartbeat that Amory believes he can feel as he contemplates the impact he hopes to have on the institution. However significant this impact might feel for Amory, though, he is just one student in one class of a university with a long and storied history—the scale of which Fitzgerald emphasizes in the metaphorical comparison between Amory's effect on Princeton and the inconsequential ripple of a stone thrown into a stream.
Over the course of Amory's tenure at Princeton, the school emerges as a character in its own right: a constant preoccupation that Amory manipulates, much like the women he tries to "love." Interestingly, Amory is quite fickle when it comes to his feelings about Princeton—sometimes he's obsessed with it, and sometimes he's disinterested in it. All in all, though, he's primarily concerned only with what he stands to gain from his relationship to the school.
In Book 1, Chapter 3, Monsignor Darcy shares his wisdom with Amory. Monsignor uses an extended metaphor to explain the distinction he feels between the concepts of "personality" and "personage"—and why a person ought to cultivate the latter rather than the former:
Now a personage, on the other hand, gathers. He is never thought of apart from what he's done. He's a bar on which a thousand things have been hung—glittering things sometimes, as ours are; but he uses those things with a cold mentality back of them.
Monsignor offers this definition to help Amory in his struggle to figure out how exactly he is supposed to become a fully realized person and who that person is supposed to be. Monsignor argues that Amory should be like a "bar" on which ornaments are hung—a bit like a holiday decoration, always growing and changing with the addition of new "ornaments," or deeds. Later on in the same scene, Darcy elaborates:
Now you've a clean start—a start Kerry or Sloane can constitutionally never have. You brushed three or four ornaments down and, in a fit of pique, knocked off the rest of them. The thing now is to collect some new ones, and the farther you look ahead in the collecting the better. But remember, do the next thing!
By Monsignor's account, Amory can be a collection of "glittering things"—those "glittering things" can be the things he has done, and Monsignor urges him to "collect" even more. This metaphor casts Amory's moment of mid-youth crisis as a momentary loss of some "ornaments" before the inevitable accumulation of more, and therefore a rare opportunity for reinvention. In other words, Monsignor's metaphor suggests that moving through life is like collecting various experiences and that, as a result, youthful experience is a matter of doing rather than a matter of being—it's about gaining experience, not simply about who someone thinks they are. This is a distinction that Amory embraces as he turns his attention to his student roles at Princeton, the people he has met, and the status he has achieved.
In Book 1, Chapter 3, Amory has a startling run-in with his deceased friend, Dick Humbird, who appears to be stalking him in a horrifying and hallucinogenic end to an uncomfortable night out in New York. The morning after, Amory's memory of the nightmarish sequence comes back slowly, delayed by the beauty of the morning. Fitzgerald uses a metaphor to illuminate the day:
If the morning had been cold and grey he could have grasped the reins of the past in an instant, but it was one of those days that New York gets sometimes in May, when the air on Fifth Avenue is a soft, light wine.
With this metaphor that compares the feeling of the day to the taste and feeling of wine, Fitzgerald conveys the intoxicating effect of lovely weather on the mind—so compelling that Amory does not immediately contemplate the disturbing nature of the previous evening. Just a few sentences after this passage, however, when Amory and Sloane come upon the crowd of people on Broadway, the mood shatters, as he's suddenly confronted by "the babel of noise and the painted faces," which brings on "a sudden sickness."
Throughout This Side of Paradise, the environment, be it the crowd, the setting, or the weather, has extreme control over Amory's mood—a literary trope that reflects Amory's inner instability during the painful process of coming of age.
In Book 1, Chapter 3, Amory has a startling lapse in his cool, calculating demeanor as his sanity appears to waver on a night out with his friends in New York. In the sequence that follows, Fitzgerald uses a host of literary devices—including imagery, metaphor, and simile—to detail Amory's hallucinogenic feeling of horror:
There was a minute while temptation crept over him like a warm wind, and his imagination turned to fire, and he took the glass from Phoebe's hand.
Fitzgerald's language mirrors Amory's feverish state of mind through the use of tactile imagery ("warmth" and "fire"), which appears in both a simile and a metaphor. Amory's sudden feeling of temptation—the urge to indulge after an uncharacteristically sober evening—feels like a "warm wind." And then, as his mind begins to hallucinate, his brain "turns to fire." The incendiary, even violent undertone of this metaphor anticipates the horrifying sequence to come, in which Amory will see a mysterious man who seems to be his deceased friend, Dick Humbird.
Until this point in the novel, Amory has seemed to be unaffected by the sudden death of Humbird in a horrible automobile accident. The intense mood shift that this passage precipitates reflects the intensity of Amory's sudden confrontation with Humbird and, for that matter, with his own unprocessed emotions.
In Book 1, Chapter 3, the illustrious Monsignor Darcy tries to give Amory some much-needed advice. In doing so, he uses a luminous metaphor to put Amory's growing pains in the perspective of the long arc of an entire human life:
[...] and don't worry about losing your "personality," as you persist in calling it; at fifteen you had the radiance of early morning, at twenty you will begin to have the melancholy brilliance of the moon, and when you are my age you will give out, as I do, the genial golden warmth of 4pm.
This is one of many metaphors of age and the process of getting older in This Side of Paradise. Monsignor uses the imagery of changing light to reassure Amory that he is progressing and growing well and that there is much change and growth to come. At this moment in the novel, Amory just wants to be "radiant"—attractive, desirable, and high-class—and doesn't want any of this radiance to fade. Monsignor's metaphor provides some consolation that his radiance will change but won't diminish. What's more, with this use of imagery and metaphor, the text itself seems to glow with the warmth of Monsignor's words and his affection for Amory.
In Book 1, Chapter 4, Amory's cynicism begins to waver. As he hears from Burne Holiday about the movement against Princeton's eating clubs, Fitzgerald uses a metaphor to illustrate Amory's newfound appreciation for Burne's sincerity:
Amory was struck by Burne's intense earnestness, a quality he was accustomed to associate only with the dread stupidity, and by the great enthusiasm that struck dead chords in his heart. Burne stood vaguely for a land Amory hoped he was drifting toward—and it was almost time that land was in sight.
In this metaphor, Amory is lost at sea. His values are in constant flux, and he is critical of himself and others—he is untethered to everything other than his own status. According to this metaphor, Burne is Amory's saving grace: he's land on the horizon, a sign of stability and literal grounding that could give Amory some sense of direction. Burne's enthusiasm for his cause and his eagerness to debate it with his friends shows Amory what good can come of a value system. Whether or not he is fully aware, he begins to gravitate towards this more honest disposition. This sequence is a turning point in Amory's coming of age; it's the moment at which Amory—who has until this moment been an unmoored character—begins to understand that there is more meaning in life than status alone.