Just looked it up, the title sounds intriguing. I often think about it, and have talked about the need for slowing down in today's world with friends. How are you liking the book? Sounds like something worth reading.
So far I have only been about a quarter into the book, and I would say I am liking it.
I have read another book earlier on this same topic - "In Praise of Slowness" by Carl Honore, which is a more formal, evidence based treatment of the subject ( as almost all popular science books are) - while this book by Haemin Sunim is a more informal approach, and I'd say based more on the writer's experience.