Thirst for knowledge

Ren Zu and Great Strength True Martial cross into Qian Kun Crystal Wall, a wall shaped like a giant mirror that reflects everything happening in the world and holds all its secrets past and present. Endless sensations overwhelm Great Strength True Martial, and the two are separated inside a boundless whiteness; searching for his son, Ren Zu instead finds Book Mountain, a peak built of paper rock and ink rivers, and its village of inkmen. An inkman tells him no person has ever arrived here before, and the elder explains that Ren Zu, reduced to bones with no senses left to him, can roam the wall without dying of the information overload that kills anyone else. He leads Ren Zu up the mountain to its ink waterfall and spring, where splashing ink forms written texts. Ren Zu leaves ink texts behind as reference points that fade over time. Once he reunites with Great Strength True Martial and shares them, his son turns the flooding information into literary tiles that free him from the overload, letting him see and hear clearly again and walk on solid ground. Back at the village, Ren Zu asks how to find wisdom Gu. ^{ch. 2160}

The elder answers that wisdom Gu hides too deep for ink texts alone, and that only turning information into knowledge, with memory Gu to hold it and cognition Gu to refine it, can cut a path that reaches far enough. Ren Zu gathers bookworms from Book Mountain and works with cognition Gu to build his knowledge into a path of ink text. A first attempt ends short of finding wisdom Gu for want of enough knowledge, so he and his son return to Book Mountain and gather still more before trying again. The second attempt fails as well, despite his mind feeling completely full, and when self Gu tells him to look closer he finds a Gu lodged in his mind and taking up the room. The Gu names itself pride Gu and refuses to leave. Ren Zu cannot drive it out himself, so Great Strength True Martial hands him humility Gu, which chases pride Gu out of his mind and onto Great Strength True Martial instead. Humility leaves Ren Zu feeling he always lacks knowledge, so he keeps gathering it past every limit and ignores self Gu’s warning to stop, until his mind bursts and a little girl rises from the scattered knowledge, calling him father and naming herself his daughter Carefree Wisdom Heart. ^{ch. 2161}