Yoga, as a system of preventive medicine based on a programme of physical and mental exercises, made it possible to control voluntarily functions which are normally automatic; as part of a spiritual discipline, Hindu or Buddhist, it prepares the way for the extinction of individual self-conciousness. "Fear", said the book, "arises when there is another". So if there is no other person in the world, there can be no fear. Exercises, under the guidance of a guru, taught the disciple that his individuality was an illusion and his soul part of the universal soul. The price of banishing fear, in other words, is to cease to be a person in the normal sense.