Final answer:
Holden Caulfield demonstrates authenticity through his disdain for superficiality and the genuine grief and protection he exhibits towards his deceased brother's memory.
Step-by-step explanation:
The question asks why Holden Caulfield from "The Catcher in the Rye" is considered not a phony. One piece of evidence suggesting Holden's authenticity is his consistent disdain for superficiality which he observes in adults and peers; he frequently voices his discomfort with people who are inauthentic.
This may be interpreted as Holden’s own commitment to being genuine. His reaction to the death of his brother Allie is another testament to his depth of feeling and authenticity.
Holden is deeply affected by this loss, and he regards Allie's innocence as something pure and genuine, which he seeks to protect in other children, thus showing his desire for preserving sincerity and innocence.