Holden is our central, first-person narrator, so no surprises there. Right? Well…
I'm the most terrific liar you ever saw in your life. If I'm on the way to the store to buy a magazine, even, and somebody asks me where I'm going, I'm liable to say I'm going to the opera. (3.1)
Uh-oh. What do we do with a first-person narrator who tells us straight out that he’s a liar? Can we trust anything that he says?
Well, we have to, right? In Catcher in the Rye, Holden’s perspective on maters in the substance of the novel; more than the events themselves, we're interested in what Holden thinks of the events/people/places/weather/dead mummies and how he presents them to us—a.k.a., his point of view. And here’s the thing: while Holden calls essentially everyone in the book a "phony" at some point or another (with the exceptions of Jane Gallagher, his brother Allie, and his sister Phoebe), he himself is a constant liar.
It might not be an entirely conscious snowing—he's certainly not sitting back and trying to deceive us—but putting spin on everything seems to be a real part of his persona. (Think about when he tells us about how he puked that night at the Whooton school after indulging in a bottle of scotch; he says he only threw up because he made himself, not because he had to. He's not trying to lie to us, but he's convinced himself because he wants to think he can hold his liquor.)
So, who knows? Are the people he meets really all moronic phonies?