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Quite a good book but most of the points mentioned are quite "obvious", like when to know someone is happy/sad/angry at some points the examples are VERY easy to understand in real life. It is a good intro point for NLP but a bit too much i think.
If you want to learn about facial expressions, this is the book you want. From the works of Dr Paul Ekman its amazing how you can learn all about how your face can give you away. If like me you enjoyed the TV series Lie To Me, then you need to read this book.