The extent and duration of its applicability is commensurate with the whole of humanity for all time. I shall attempt to show you the significance that Yoga holds for everyone in this great and eventful twentieth century. First and foremost, Yoga is not mere acrobatics. Some people suppose that Yoga is primarily concerned with the manipulation of the body into various queer positions, standing on the head, for instance, or twisting about the spine, or assuming any of the numerous odd poses which are demonstrated in the text-books on Yoga. These techniques are correctly employed in one distinct type of Yoga practice, but they do not form an integral part of the most essential type.
Physical posture serve at best as an auxiliary, or a minor form of Yoga.
Secondly, Yoga is not the performance of magical feats. Anything that is good is all too easily corrupted by perverted people. At all times in the history of the world this has happened. Behind the deliberate mystification of things pertaining to Yoga there lies a selfish motive. Unfortunately, the distortion of this true science is the consequence.