The main object of this book is to discuss the science of Yoga in as simple and rational a manner as possible, and also to debunk some of the nonsense that continues to be said and believed on the subject. A must for all those are eager to clarify their conception about Yoga.
The book one must read to learn natural sciences is the book of nature. The book from which to learn religion is your own mind and heart.
-Swami Vivekananda