Holden Caulfield goes on a reckless three-day journey through New York City because he is mentally unstable. At the beginning of the novel, he reveals to readers that he is in a psychiatric hospital, where he is narrating the story from. His past traumas and current issues have led him to depression. In the beginning, Holden tells readers about the two deaths he experienced. His younger brother, Allie, died of leukemia three years prior, which greatly impacted him emotionally. Additionally, a classmate of Holden's previous school committed suicide. The entire novel, Holden struggles to come to terms with growing up. He desperately tries to protect people he considers innocent while simultaneously trying to prove to readers how he can act like an adult. Depression sets in as he continuously fails at both.
Holden Caulfield didn't run away to New York City because he was depressed; he did it because he's irresponsible. After being kicked out of Pencey Prep, he does not have an adult to guide his decisions. He knew that his parents will be angry about him being expelled so he wanted to avoid going home immediately. Holden acts like a typical unsupervised teenager by sneaking into bars, flirting with women, and spending a ton of money. Therefore, he is only being reckless because he has the freedom to.
[P1] Holden Caulfield is in a psychiatric hospital. [P2] Experiencing two deaths was traumatizing to Holden Caulfield. [P3] Holden Caulfield cannot protect innocence or behave like an adult. [P4] Therefore, Holden Caulfield has depression.
Rejecting the premises
[Rejecting P4] Holden Caulfield doesn't explicitly say he was diagnosed with depression.