Temporarily abandoning everything except for some food and first aid kits, Morley, Japhy and Ray begin to climb up a long, daunting scree valley. Sore, afraid of falling, and concerned about time, Ray feels his enthusiasm begin to wane. His two companions walk ahead of him - Morley talking to himself and Japhy, without his pants, even farther ahead - but Ray lags behind, cold and afraid, until he finally decides to pass Morley. Again he has the mysterious sensation that he must have taken this journey before.
Finally, Ray reaches a glorious lake at the foot of Matterhorn and, inexplicably optimistic again, asserts that he is ready to climb to the top of the mountain. This time it is Japhy who corrects his naÃ¯ve notion: "Do you realize that's a thousand feet more?" Yet when Japhy decides to climb to the top - quickly, so he can return to camp before nightfall - Ray is determined to follow. Morley neglects to follows them and in short order Ray begins to feel that he has made a mistake. Unlike the inexhaustible Japhy, he is fatigued and afraid of the height he has reached. He mutters to himself that he should have stayed with Morley and not attempted to climb the rest of the mountain.
At last, the miserable Ray finds a comfortable ledge to rest on, and despite Japhy's prodding refuses to follow him the rest of the way to Matterhorn's peak. Above him, he hears Japhy singing triumphantly as he explores the mountaintop, both incredible and insane. At this point, though, Ray believes that the smartest of them all is Morley, relaxing comfortably near the lake, and he swears the he will never attempt this sort of climb again.
Chapter 12 begins just as Ray has reached the pinnacle of pessimism. He looks up and is astounded to see Japhy bounding and leaping fearlessly down the mountain. At this moment he has a revelation - that "it's impossible to fall off mountains, you fool!" - and imitates his co-climber, screaming back to camp. He tells Japhy that his mountaintop yodeling is the most beautiful sound he has ever heard and that he wishes it could be recorded, but Japhy seriously asserts that such a thing is not meant for those unwilling to climb the mountain themselves. Ray completely changes his mind about mountain climbing and wants to try it again now that he knows that he will not fall.
As they head back down the mountain, Ray follows a deer trail, confident that it will lead him to their watery destination, even though his friends take a different route. Surely enough, he winds up at Japhy's roaring bonfire, and comments on how extraordinarily childlike he feels. Before they begin to descend the valley of boulders, though, Ray and Japhy switch shoes in a mutually beneficial trade: Japhy can now wear the more lightweight sneakers while Ray can protect his blistering feet with Japhy's thick boots. Even so, the journey down is difficult and exhausting, and Ray lashes out angrily at his friends, who are afraid to stop and rest and insist on getting to the car quickly. Soon enough, though, they reach the peaceful meadow, and this time Ray acts as a motivator for his worried friends. As they head down the mountain, they fall into a rhythm; the air warms and the surroundings become filled with animals and plants once again. When they reach the car at last, it turns out that the night had been warm; Morley wasted his effort going back to drain the crankshaft.
Famished, the trio head over to Bridgeport again for a hot meal, where Ray discovers Japhy's weakness: he is mortified of eating at a "bourgeois" restaurant because he feels underdressed, and he is also a penny-pincher who does not want to pay for overpriced meals. Irritated, Ray finally drags him over to the "richer" restaurant, where they settle down to an enormous feast. Afterwards they buy some alcohol in a liquor store, thoroughly shocking the storekeeper and his friend when they tell them they have just climbed Matterhorn.
Ray falls asleep in Morley's car and his friends wake him up as they drop him off at home. When he wakes, happily, the next morning, he finds that the veins in his feet no longer have blood clots; he has worked them out of his system.
In Chapter 13, Ray is alone in his cottage when Princess bikes over and says that she can stay for a while as long as she calls her mother, so they walk over to the pay phone at the local gas station so she can do so. After an hour of erotic play and their usual bath together in the hot tub, Princess leaves, but Japhy and Coughlin, and eventually Alvah, show up and a night of drunken revelry begins. After trekking noisily down the street carrying enormous garden flowers and bursting in on a nervous University of California English professor, the three men return to Ray's cottage and begin to talk.
A large part of the friends' conversation is comprised of half-nonsensical poetry and guitar-song filled with rhyme and Buddhist thought. Japhy wants to start a revolution of Zen Lunacy, which he feels is an ideal that the conformists of America should - but unfortunately do not - understand. Ray and Japhy, especially, indulge in crazy fantasies: they want to create a "floating zendo" for "wandering Bodhisattvas" in which Japhy is a head priest "with a big jar full of crickets," free and unconstrained by the American political and judicial system. Japhy also talks about Hakuyu, a fabled wanderer who meets an ancient old man with the secrets to mind-tripping meditation. Alvah, while somewhat skeptical of these ideas, eventually lets go and also immerses himself in their dreams. The night ends with Ray and Coughlin drunkenly wrestling each other and creating a few holes in the wall.
The omniscient Ray, who is narrating these past events chimes in at the end of the chapter with a fond acceptance of this wild time. According to Ray, there is a sort of "wisdom" to be found in the lifestyles and thoughts of the Zen Lunatics.
Kerouac begins Chapter 14, telling us that Ray, newly inspired, has formed the intention to become a sort of "rucksack wanderer" himself, carrying on his back a pack with all necessities, living in neutrality in a remote location. He notes that his ideal is somewhat different than both Japhy's and Alvah's.
In accordance with this plan, he, Japhy, and Alvah go shopping together, buying clothes and equipment at Goodwill, Salvation Army, and Army Navy stores. Everything that Ray buys is remarkably cheap as well as practical: aluminum pot holders, a used sleeping bag, gloves, multipurpose nylon coverings, a canteen, and cooking utensils, for example. Japhy, true to his charitable nature, also gives Ray some gifts, the last of which is a tablespoon with a twisted handle useful for pulling a pot out of a fire. The protagonist feels remarkably refreshed and happy.
As Chapter 15 begins, Ray, with his rucksack on his back, ambles merrily over to a cafÃ© where the denizens of "Skid Row" believe he is going uranium hunting. The protagonist plays along, but secretly harbors supercilious notions about these men who think that money is actually valuable. In the scene that follows - unquestionably the novel's darkest to this point - Ray goes to visit his friends Cody and Rosie (first introduced at the poetry reading in Chapter 2) only to find that Rosie looks emaciated and terrified, and has tried unsuccessfully to slit her wrists with a dull knife. According to Cody, she wrote out a list of all of her friends' sins and tried to flush it down the toilet at work. Unfortunately, she succeeded only in backing up the plumbing, and became convinced that the sanitation worker who fetched the list was actually a policeman and that soon they would all be arrested. Cody asks Ray to watch Rosie for him while he works that night, but Ray is irritated and protests that he "was planning on having fun tonight." Cody retorts that he needs to learn some responsibility.
At a nearby cafeteria, the paranoid Rosie - convinced that the cops are going to arrest her and her friends and subsequently take over the world - argues vehemently with Ray, who tries in frustration to convince her not only that she is delusional but also that the world is illusory. Eventually she seems to recover and begins to eat and talk in a semi-normal way. But later that night, after Cody returns and Ray leaves, she breaks the skylight in order to get jagged glass to cut herself with. When her shocked neighbors call the police, she commits suicide by jumping out of a sixth story window. At this point, Ray decides to leave the city, continuing to think that Rosie's problems would have been solved if she only knew the world's true nature.
Like the chapters before it, this part of Kerouac's novel is filled with a sort of spirited hope that originates in large part from overcoming fear in favor of spontaneity. Chapter 12 holds one of the most important ideas in The Dharma Bums. The first sentence of the chapter is short, terse, and thoroughly negative: Ray complains about his decision to follow Japhy up to Matterhorn, feeling foolish and miserable. But the very next sentence is astoundingly different in, tone, style, and content. Ray says that
"suddenly everything was just like jazz...I looked up and saw Japhy running down the mountain in huge twenty-foot leaps, running, leaping, landing with a great drive of his booted heels...and in that flash I realized it's impossible to fall off mountains you fool and with a yodel of my own I suddenly got up and began running down the mountain...." The protagonist has found his "rhythm" again; he is miraculously invigorated. Kerouac's rushing and rambling sentence mimics both Ray's giddy rush of euphoria and his swift descent down the mountain, ending, appropriately, when Ray hits the ground.
Yet it is impossible to ignore how quickly Ray's mood oscillates during these chapters. As mentioned above, his cataclysmic invigoration occurs within the span of one sentence. When he is huddled near the top of Matterhorn, he can think only of coming down; when he descends the mountain, he wants nothing more than to go back up. Even Ray takes a somewhat objective perspective on his own emotions as when he says, for example, that "Whether you can fall off a mountain or not I don't know, but I had learned that you can't. That was the way it struck me." And during the descent back to the car, Ray's mood shifts rapidly from happiness to weariness and back again so swiftly that the reader cannot help but see flaws in his "perfect" lifestyle. What is undeniably true, however, is that the emotions Ray feels, however inconsistent, are remarkably pure and intense.
In these chapters there exists for the first time a clear disavowal of Dharmic principles in favor of practicality. When huddled on the ledge on Matterhorn, fatigued, cold, and frustrated, Ray calls his own idol Japhy a "damn mountain goat," and thinks that inspiring Zen quotes such as "when you get to the top of a mountain, keep climbing" are nothing more than "cute poetry." Furthermore, Ray becomes irritated when Japhy refuses to eat at the better of two restaurants. He muses, with a hint of scorn, that "this little tough guy who wasn't afraid of anything and could ramble around mountains for weeks alone and run down mountains, was afraid of going into a restaurant because the people in it were too well dressed." Ray seems to have a sort of implicit understanding that being a Dharma Bum is sometimes overly idealistic.
Kerouac, too, portrays Ray as impractical, callous and unfeeling in Chapter 15 - which, with its inclusion of Rosie's suicide, is the darkest in the novel. Any sympathetic reader would agree that Ray's attitude - he would rather "have fun" than take care of his suicidal friend - is heinously selfish. Furthermore, his advice (however well-meaning) that her cares are nothing more than part of a void soullessly trivializes the concerns that are visibly ruining her. After Rosie's death, Ray seems to feel neither guilt nor sadness, but rather condescension: "And if she had only listened to me..." In many senses, the reader is made to understand his attitude as unforgivable. Such an attitude dulls the glitter of Dharma that is portrayed so favorably and idealistically in other chapters.
This chapter also includes a brief scene in which Ray and Princess partake in yabyum. While the act itself is uneventful, Ray quips very tellingly that "Poor Princess...meant every word she said [about being a Bodhisattva]." This single line carries with it the weighty insinuation that while Princess may take her Buddhist notions seriously but that Ray and his friends do not. This is further evidence that Japhy and his friends have misogynistic tendencies, humoring women in order to take advantage of them.