"We are healthy only to the extent that our ideas are humane."
This is the epitaph on the monument built for Trout after he died. It is "a quotation from his last novel, his two-hundred-and-ninth novel, which was unfinished when he died." After Dwayne Hoover went to the asylum, Trout became obsessed with the with the notion that ideas can cause disease, as well as cure it. At first he was just "a dirty old man," but soon his ideas were taken seriously by artists and scientists alike.
"What is the purpose of life?"
Trout sees this message written on the tiled wall of the pornographic movie house on Forty-Second Street. He cannot write a response because he has no writing utensil, but wants to write:
"To be the eyes and ears and conscience of the Creator of the Universe, you fool."
"Everything you're not supposed to do to a car, they did to a car."
Dwayne says this while telling Francine about a trip he made to the headquarters of the Pontiac Division of General Motors, three months after his wife's suicide. He had witnessed the destruction of Pontiacs by scientists. The sign on the door read, Destructive Testing. Dwayne wonders aloud, "if that was what God put me on Earth for - to find out how much a man could take without breaking." This anecdote further underlines the theme of humans as machines, specifically as cars, once again. It also foreshadows Dwayne's mental breakdown brought on by Trout's book that convinces him that he is the only human in the world. He feels very alone, as if God had a destructive plan for him, and thus it is easy for him to be pushed over the edge when Trout's written words speak to him.
"Wayne should have pricked up his ears at that. That particular drink wasn't for any ordinary person. That drink was for the person who had created all Wayne's misery to date, who could kill him or make him a millionaire or send him back to prison or do whatever he damn pleased with Wayne. That drink was for me."
This passage occurs in the cocktail lounge of the new Holiday Inn, when Wayne Hoobler overhears the narrator order a drink. It introduces the narrator's full involvement as a character in his own created universe. We as readers see mirrors acting as "leaks" in the form of the narrator's reflective sunglasses, as he watches his characters interact and controls them to the extent that he can.
"Still wavin', man."
Eddie Key says this very quietly as he drives Martha the emergency vehicle filled with Dwayne Hoover and all his victims. He focuses his eyes on an American flag stuck to the windshield, and says this quotation for the benefit of his ancestor, Francis Scott Key. This line is a beacon of hope; perhaps the only clear one in the whole story. Despite all the destruction in the very vehicle he is driving, Eddie Key feels himself to be a vehicle through which history continues to be made, building upon itself through generations of Americans.
"Trout felt nothing now that millions of other people wouldn't have felt - automatically."
This quotation is from the Epilogue, as Trout wanders past the morgue and the x-ray room, and "automatically mooned about his own mortality." The narrator uses this opportunity to again remind us of his opinion that humans are machines: Even as Trout experiences the most aware, seemingly human feelings of questioning one's mortality, he is acting in accordance with his machinery.
"I thought it would be a good idea to let him have a good look at me, and so attempted to flick on the dome light. I turned on the windshield wipers instead. I turned them off again. My view of the lights of the County Hospital was garbled by beads of water. I pulled at another switch, and it came away in my hand. It was a cigarette lighter. So I had no choice but to continue to speak from darkness."
The narrator attempts to turn on the dome light in his car, to let Trout have a look at him. However, he is unable to control the machine that is his automobile just as he is unable to control the machine-characters in his created universe. This scene is significant because it is an allegory for the Creator of the narrator's universe, as well as that of the reader. The car, in addition to Trout himself, is a metaphor for the Creator's characters; this metaphor has been built up throughout the story by the theme of humans as machines. It seems to have its own free will as the narrator tries to control it, in order to reveal himself as Creator to Trout.
"I hold in my hand a symbol of wholeness and harmony and nourishment. It is Oriental in its simplicity, but we are Americans, Kilgore, and not Chinamen. We Americans require symbols which are richly colored and three-dimensional and juicy. Most of all, we hunger for symbols which have not been poisoned by great sins our nation has committed, such as slavery and genocide and criminal neglect, or by tinhorn commercial greed and cunning."
The narrator says this to Trout in the Epilogue, after noisily getting out of his car. He tells Trout that he is holding something in his hand, even though there is nothing there; such is his power over Trout that he will see whatever the narrator wants him to. Eventually, Trout sees an apple; fittingly, since an apple is in fact "richly colored and three-dimensional and juicy," and has come to represent the United States.
This quotation suggests that any symbolism the reader has found in the story is merely the creation of the reader, searching for meaning. This is assuming the reader is American, since this search for symbols is described as a uniquely American quality. An example we have seen of this is the symbol "Goodbye, Blue Monday," which, despite all the meanings heaped upon it throughout the story, has been demonstrated to be empty after all, when Dwayne Hoover shouts it out randomly in the ambulance. The "tinhorn commercial greed and cunning" refers to the theme of advertising, which has permeated the story.