When authors bring in their personal life to nonfiction, it is usually too much for me. Siddhartha is a great example of how frequently I like author experiences to sleep into nonfiction. His personal account at the end is so relevant to the entirety of part 2 and serves as an outstanding way to finish it off.
Also, I really enjoyed the discussion on the Delphic boat parable. He finds such interesting ways to discuss complicated material.