Book in categories:
historical fiction

Musashi: An Epic Novel of the Samurai Era

Comments and mentions from HN threads:

Ask HN: What books fundamentally changed the way you think about the world?

ravishi: I still can't put into words how this book changed my world view, but it was one of the most impacting books I've ever read. From religion to arts to personal goals, everything changed with this book. I'm pretty sure I left the church while/right after reading it.

Ask HN: Best books you read in the past decade?

matwood: The lessons about life and finding my path shaped me probably more than any book I've ever read.

Ask HN: Books that change your way of thinking?

shantanubala: I remember Sebastian Marshall recommending Musashi by Eiji Yoshikawa -- I'd recommend it too. It's pretty good, and I was especially interested since I've been doing marshal arts for over 10 years now.