This shows that there is a mystery that lies behind movement. There are certain vibrations which take a particular direction under certain conditions, and the visible signs of all vibrations can be seen either in man's movements or in the expression of his countenance. It does not take one moment for the expression to change from pleasure to pain, from calm to horror, from love to hate. That shows that all the atoms of man's body -- the veins, tubes and muscles, and the lines formed by their movements -- are under the control of the heart. And every change that takes place in the heart shows on man's face, so that one who knows the language can read it.