This book actually taught me how to live my life happily - I mean, most of our stress and sadness comes from other people, what they say, what they will think and how they will perceive us.
This book is about finding meaning in important things in life and only having those values that an individual can control. Its like telling us to just don't bother on things that we cannot control it will just make us angry, sad and depressed if we keep trying to make everything in control.
If I am gonna rate this book, I will give it a perfect 10/10 - I live my life now applying the things that I learned from reading this book and I can say, that I am happier than I was before - since I learned to not think about how other people will think of me. We only get to live once, why live for others? we should start living for ourselves.