What does that mean monster?
Holden Caulfield is whining all the time about his circumstances, he seems like a spoiled kid until this very quote, when all his idealism is shown. He wants to be like a centinel, a watchman or a guardian angel for the innocents that may fall into the cliff cause they are unaware. A metaphor to wake up the counciousness against the perils of the status quo. Is interesting how controversial this novel has become. Several serial killers and even politicians were inspired by it :@