Siddhartha by Hermann Hesse (1922)

A seeker meets the Buddha himself, the fully awakened one, listens to a teaching that has no flaw in it, and then walks away. He cannot be given wisdom, Siddhartha understands; he must live it, every error of it, in his own body. So he plunges into the world he renounced: the courtesan Kamala teaching him love, the merchant teaching him greed, the dice and the wine teaching him despair, until a son he adores breaks his heart exactly as he once broke his father's. Then he comes to the river, and learns to listen to it. Hesse wrote this slim, luminous book out of his own collapse, and it carries the strange calm of someone who has stopped fighting the current. Its great gift is the river's secret, that time is not real and every voice of the world is one voice saying Om. Few books make peace feel so hard-won, or so close.