Siddhartha
A Brahmin's son walks out on every teacher he meets — including the Buddha himself, to his face — because the one thing he wants cannot be handed over. Hesse sends him through asceticism, sex, money, and despair before he ends up beside a river with an old ferryman, listening. The novel's whole argument sits in that refusal: knowledge can be taught, wisdom has to be lived through, and no doctrine survives the transfer. Hesse wrote it in a decade of personal collapse and psychoanalysis, and it reads that way — a German Protestant working out his own salvation in Indian dress. Sixty pages of parable that have outsold libraries of philosophy.
The India here is a German Romantic's India — more Schopenhauer than dharma, and the hero's serene self-realization runs closer to Vedanta than to anything the Buddha taught, which is presumably why Hesse has him decline the Buddha in chapter three. The incantatory simplicity that reads as profound at nineteen can read as greeting-card mysticism at forty. Kamala exists to teach love and then die conveniently; every stage of the journey arrives on schedule, like stations on a commuter line to enlightenment. Keep it on the shelf next to its critics.
The case for it and the rest of the canon open with Pro.