The second obstruction is doubt; we always feel doubtful about things we do not see. Man cannot live upon words however he may try. So, doubt comes to us as to whether there is any truth in these things or not; even the best of us will doubt sometimes: With practice, within a few days, a little glimpse will come, enough to give one encouragement and hope. As a certain commentator on Yoga philosophy says, "When one proof is obtained, however little that may be, it will give us faith in the whole teaching of Yoga." For instance, after the first few months of practice, you will begin to find you can read another's thoughts; they will come to you in picture form. Perhaps you will hear something happening at a long distance, when you concentrate your mind with a wish to hear. These glimpses will come, by little bits at first, but enough to give you faith, and strength, and hope. For instance, if you concentrate your thoughts on the tip of your nose, in a few days you will begin to smell most beautiful fragrance, which will be enough to show you that there are certain mental perceptions that can be made obvious without the contact of physical objects. But we must always remember that these are only the means; the aim, the end, the goal, of all this training is liberation of the soul. Absolute control of nature, and nothing short of it, must be the goal. We must be the masters, and not the slaves of nature; neither body nor mind must be our master, nor must we forget that the body is mine, and not I the body's.