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.
Take up one idea. Make that one idea your life -- think of it, dream of it, live on that idea. Let the brain, muscles, nerves, every part of your body, be full of that idea, and just leave every other idea alone. This is the way to success, and this is the way great spiritual giants are produced. Others are mere talking machines.
-Swami Vivekananda