This book is justly famous as a superb distillation of the main principles of Raja Yoga, presented in a manner best suited to western minds. First published in 1906, it was written by William Walker Atkinson, an intensely secretive occultist, who authored many works under various pseudonyms, including Yogi Ramacharaka. Alongside its philosophical content, the book includes numerous mental exercises. Some are designed to increase the control and enjoyment we have over our own lives, while others aid in the development of occult powers and move the developed soul towards that ultimate spiritual experience - Illumination.