A newly revised an expanded version of a popular an unique work, this extraordinarily valuable introduction discussion of the philosophy of hath yoga is indispensable to any student of yoga. This clear and easy to follow exposition views hatha within the framework of raja yoga, the yoga of eight complements, as promulgated by Pantanjali, the author of Yoga Sutras, the most authoritative text on the science of yoga. Hatha should not be merely a system of physical exercise: this work emphasizes the paramount role that the mind plays in hatha yoga, and demonstrates how to elevate the practices of hatha to an inner spiritual experience. This study outlines how the practice of hatha yoga can serve as a means to understand the subtler essences of mind and prana and to prepare for meditation and the awakening of the kundalini force.