Here I should like to draw your attention to the Reserve Power existing in your body. Of course there are soul-powers existing potentially within YOU which leap into brilliant expression as you succeed in developing and expanding your brain to a state of perfect responsiveness to the touch of your will. For really and truly your will, forming as it does the divine part of yourself, is always strong and must unfold "as a rose" by exercising itself, in the field of matter, force and mind;--all of which are subordinate to YOU and the real aim of human evolution is actually to place in your hands the wand of power. What is within your body is sure to find its correspondent outside in Nature. Control nature inside and you will move as a master out in this universe. Now without going into details let me tell you--if you do not know it already--that mind is the finest form of matter, and matter the grossest form of mind, and there is a constant interaction between the two poles. But since mind represents the positive end and matter the negative, the former can dominate the latter. You can evoke states of consciousness by applying stimulus to the periphery and again mental states evoke corresponding vibrations in the cellular life of body and brain. Hence you see your mind controls and forms your body. Also your body reacts upon your brain and affects that part of your mind which has to operate through the brain, which is matter pure and simple. So to keep aright the polarities of your brain and body a constant adjustment of forces is needed and thus you can establish POISE. In order always to be in a state of perfect health two things are necessary. Deny the power of disease over yourself. In the unyielding will is health. In the weak, vacillating, fearful mind is disease and death. At the same time always be in perfect magnetic trim with the physical laws of health. A knowledge of the latter and the ascension of a fearless mental attitude will open up hitherto unrecognised channels of physical and mental expression. Physiological researches have led sincere investigators to the inevitable conclusion that there is subtle, refined, dynamic substance, a reality that binds up the reorganization, causes growth, vitality and motion; repairs injuries; makes up losses; overcomes and cures diseases. Von Helment called it "Archeus"; Stahl called it "Anima;" Whytt called it the "sentiment principle;" Dr. Cullen called it "Caloric;" Dr. Darwin called it "Sensorial energy"; Rush called it "Occult cause;" and many other names such as "Vital Principle," "Living power," "Conservative Power," "Odic Force," etc., etc., have been given to it. We of India have recognised it and devised Yoga methods for controlling it; we call it Prana and only in India do you come across men who possess pranic control or control over universal energy.