In The Dharma Bums, Japhy is modeled after Snyder, Alvah Goldbook after Allen Ginsberg, Warren Coughlin after Philip Whalen, Henry Morley after John Montamery, and Rheinhold Cacoethes after Kenneth Rexroth. Ray Smith the narrator is supposed to be Jack Kerouac himself.6
Ray and Japhy went to climb the Matterhorn. It was tougher and more dangerous when they get closer to the peak. Japhy finally made it to the top while Ray didnt. cuz the strong feelings of horror and fear stopped him.
When Ray was having the inner struggle of keep going or not, he saw Japhy running down the mountain in huge 20-foot leaps and yelling crazily.
That was the moment when Ray suddenly realised how human and nature connect and merge. He told himself there is no need to feel horror. Then he started to run and jump and leap as Japhy did like a zen lunatic. He felt no fear at all and found himself reborn.
"Ah Japhy you taught me the final lesson of them all, you can't fall off a mountain."
I like this paragraph is not because they proved it is 100% safe to run and jump on a mountain, but they bring up the spirit of Zen buddism that is - staying away from the secular world and get back to nature. I believe that experience definitely influenced his future decision of being a mountain lookout.
In this book, Japhy is Cold Mountain. Through the body of Japhy, Kerouac describes how cold mountain is like in his mind. He expressed his understanding of Zen.