looking for a book that slowly changes your perspective

I’m not necessarily looking for something fast-paced or plot heavy, but a book that stays with you and quietly shifts how you think over time

for example, I’d recommend Siddhartha by Hermann Hesse It’s a short read, but it explores ideas about purpose, identity, and finding your own path in a really simple yet deep way It doesn’t try to give you direct answers, which is what makes it stick

Any other books like this that had a similar effect on you and what made them stay with you?