Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
By writing with a more abstract, distant tone, Hesse gives his story a certain amount of gravitas. And by "a certain amount" we mean a lot:
Slower, he walked along in his thoughts and asked himself: "But what is this, what you have sought to learn from teachings and from teachers, and what they, who have taught you much, were still unable to teach you?" And he found: "It was the self, the purpose and essence of which I sought to learn. It was the self, I wanted to free myself from, which I sought to overcome. But I was not able to overcome it, could only deceive it, could only flee from it, only hide from it. Truly, no thing in this world has kept my thoughts thus busy, as this my very own self, this mystery of me being alive, of me being one and being separated and isolated from all others, of me being Siddhartha! And there is no thing in this world I know less about than about me, about Siddhartha!" (4.3)
This makes sense—talking about enlightenment in casual terms does a real disservice to the subject.