Holden wonders around his old school after leaving a note to Phoebe and finds the words 'fuck you' written on the walls. Depressed he then wanders to the museum and finds there in the hall leading to the mummies the filthy words staining the wall. Angry, he muses that someone will probably write these words on his tombstone. This is the last straw and Holden's last stand in defending innocence. He cannot fathom why someone would put these words where kids would see them and in turn imitate them.
"It drove me damn near crazy. I thought how Phoebe and all the other little kids would see it, and how they'd wonder what the hell it meant, and then finally some dirty kid would tell them--all cockeyed, naturally--what it meant, and how they'd all think about it and maybe even worry about it for a couple of days. I kept wanting to kill whoever'd written it."
"If you had a million years to do it in, you couldn't rub out even half the 'fuck you' signs in the world. It's impossible."
While walking down the street in New York, Holden witnesses a small child singing about a body coming through the rye. Later he relays this to Phoebe, she immediately corrects him on that it is actually a poem by Robert Burns. It was the moment when Holden hear the child singing though he realized that he wanted to be the catcher in the rye. The protector of children and their innocence.
"Anyway, I keep picturing all these little kids playing some game in this big field of rye and all. Thousands of little kids, and nobody's around - nobody big, I mean - except me. And I'm standing on the edge of some crazy cliff. What I have to do, I have to catch everybody if they start to go over the cliff - I mean if they're running and they don't look where they're going I have to come out from somewhere and catch them. That's all I do all day. I'd just be the catcher in the rye and all. I know it's crazy, but that's the only thing I'd really like to be."
Holden speaks so wonderfully of his younger siblings. Always noting on how smart the both of them were and how he preferred their company to anyone else's. Allie and Phoebe are the epitome of innocence to Holden. After the loss of Allie he will do anything to protect Phoebe and keep from loosing her.
"He was terrifically intelligent. His teachers were always writing letters to my mother, telling her what a pleasure it was having a boy like Allie in their class. And they weren't just shooting the crap. They really meant it. But he wasn't just the most intelligent member in the family. He was also the nicest, in lots of ways."
"She put her arms around my neck and all. She's very affectionate. I mean she's quite affectionate, for a child. Sometimes she's even too affectionate. I sort of gave her a kiss, and she said "Whenja get home?" she was glad as hell to see me. You could tell."
"Boy, you have to watch her every minute. If you don't think she's smart, you're mad."
Throughout the novel Holden is always paying special attention to girls. He has one soft spot for Jane. When he arrives in NYC Holden tries to woo two older ladies at a bar. Later he calls Sally, an old acquaintance, and hires a prostitute by the name of Sunny. This interest in the opposite sex shows part of Holden's internal battle over innocence. While innocence is something he treasures he gives into desires that are not innocent.
"When a girls looks swell when she meets you, who gives a damn if she's late?"
"That's the thing about girls. Every time they do something pretty, even if they're not much to look at, or even if they're sort of stupid, you fall half in love with them, and then you never know where the hell you are. Girls. Jesus Christ. They can drive you crazy. They really can."
When Holden first arrives in NYC the first taxi driver he talks to he asks about the ducks in Central Park. He later asks a second driver about the ducks as well and as the first one did the second followed in scoffing at Holden's question and blowing him off. The ducks symbolize a childish place inside of Holden, one that he wants to hang on to. Holden is a very large supporter of preserving innocence and anything that threatens that frightens and angers him.
"You know those ducks in that lagoon right near Central Park South? That little lake? By any chance, do you happen to know where they go, the ducks, when it gets all frozen over? Do you happen to know, by any chance?"
Holden is a nicotine addict. Through out the course of the novel he manages to drag down cigarette after cigarette. He even takes some from his family's home the night he sneaks in to see Phoebe. Holden criticizes people for doing harmful things and constantly calls people out on being 'phony.' While in fact Holden can be taken into regards as a phony himself.
"When they got up to go, the two nuns, I did something very stupid and embarrassing. I was smoking a cigarette, and when I stood up to say goodbye to them, by mistake I blew some smoke in their face. I didn't mean to, but I did it. I apologized like a madman, and they were very polite and nice about it, but it was very embarrassing anyway."
After leaving Pencey Prep Holden makes his way New York before going back to his parents house. While in the Big Apple Holden thinks of his younger sister Phoebe frequently. While in the city he buys her a record, "The Little Shirley Beans." He regards this as a kids record while at the same time regarding Phoebe as a woman for her intelligence. This is way of recognizing that she contains much innocence. Though, he does become annoyed whenever she criticizes him as an adult would do. Shortly after the purchase of the record Holden drops it while drunk and it shatters on the ground, a symbolism for the loss of innocence. Phoebe is an important to Holden as she is very much the female version of Allie. Holden wants to protect her from the evil in the world and not lose her like he lost Allie.
"All the kids kept trying to grab for the gold ring, and so was old Phoebe, and I was sort of afraid she'd fall off the goddam horse, but I didn't say anything or do anything. The thing with kids is, if they want to grab for the gold ring, you have to let them do it, and not say anything. If they fall off, they fall off, but it's bad if you say anything to them."
Holden wonders around his old school after leaving a note to Phoebe and finds the words 'fuck you' written on the walls. Depressed he then wanders to the museum and finds there in the hall leading to the mummies the filthy words staining the wall. Angry, he muses that someone will probably write these words on his tombstone. This is the last straw and Holden's last stand in defending innocence. He cannot fathom why someone would put these words where kids would see them and in turn imitate them. 
