It can, of course, be seen at once that expansion is due to the activity of the extensor muscles. The stretch is, in the main, an expansion. At any rate, it is always associated, co-ordinated, when properly performed, with expansion. Moreover, if we observe the action of animals and all true spontaneous actions in a human being, we observe that the activity of expansion begins in the centre of the body. It is at this point that we should initiate our expression. The actions in the middle of the body are more conditional than those in the feet, hands, or limbs, but the awakening of conditions should precede modulation. A certain activity of expansion and diffusion is the very basis of all conditions. All exercises should naturally begin with expansion. A true exercise means an increase of activity. Moreover, not only does life expand, but all positive emotions, such as joy, love, courage, cause activity of the extensor muscles. These emotions, as is universally known, improve health. If we observe the structure of the torso, we find that the chest has no prop from below; that the ribs are placed at an angle with the spine, sloping downwards as low as forty-five degrees, while at times they may be lifted seventy-five or eighty degrees or more. The expansion of the chest lifts the ribs. If we study a skeleton, we see that it must be suspended, that it cannot be propped up. Man, accordingly, stands and walks primarily on account of the active expansion of his whole chest. He is the one animal that has levitation, as will be shown later. We find that under the ribs in the torso are all the vital organs. The lungs, the heart, the stomach, all these depend for their normal position, their normal action upon the expansion of the chest. When a man stands, the tendency for the chest is to sag. There are no bones to elevate it. Man has levitation as well as gravitation, and the expansion and elevation of the chest lie at the basis of all good position in standing, sitting and also walking. There are certain co-ordinate curves, beautiful, spiral, rhythmic, in a normal and healthy human being. These curves depend upon this expansion of the chest. All the best gymnastic exercises centre in the development of activity in the muscles concerned in keeping the chest elevated and harmoniously expanded. When we study the expression of this part, we find that it reveals energy and courage and all the noble, positive emotions of a human being. A passive chest expresses indifference, inactivity, fear, discouragement, a sense of weakness, unwillingness to awake and rise up to meet emergencies. A sunken chest, accordingly, is an indication of a tendency to disease, simply because it expresses a negative mental state or one favorable to the reception of abnormal conditions.