should worry cause the muscles of the stomach to stop completely, thus bringing on thousands of attacks of acute indigestion? We now have a clue to the meaning of these facts, which is about as follows: The emotions are to be looked upon as part of the machinery by which bodily well-being is promoted. Emotions of pleasure signify that matters are progressing favorably, and the nervous discharges accompanying these emotions are those in accord with well-being. For example, the activities of the alimentary tract in digestion are of a kind that prosper when the body as a whole is well off. Disagreeable emotions, on the other hand, are associated with the necessity for self-preservation. Thus anger or fear arise in the presence of an emergency calling either for combat or flight. The nervous discharges that accompany these emotions are found on analysis to bring about bodily changes whose effect is to prepare the body successfully for one or the other. This is best shown by actually naming over some of the bodily changes that occur. We may begin with the top of the head and work down. The hair stands on end; this is of no importance in human beings, but in many animals contributes materially to the ferocity of the appearance. The pupils are dilated, aiding vision; the face is pale, and the mouth is dry; not because these in themselves are of importance but because they represent a diversion of energy from unimportant to important parts of the body. The blood that ordinarily flows through the face is shunted out of it into the brain and muscles, where it will really help in the emergency. The activity of the salivary glands is stopped to free the energy that they would consume for use in the brain or muscles. The heart beat is quickened; this again, by making the circulation more efficient, helps the animal to fight effectively. The activity of the stomach is suspended for the same reason as is that of the salivary glands. What we have is a marshaling of the bodily forces into the organs which are of immediate importance in meeting the emergency; namely, the nervous system and the muscles. The other parts of the body, which are necessary in the long run, are allowed to stop functioning for the moment. This behavior of the body in an emergency illustrates better than anything else could the point that our muscles, nerves, and sense organs make up the really important parts of us and the rest of the body has simply the duty of keeping these in good order. In time of emergency all the energies are devoted to the task of keeping these parts of us at highest efficiency, however bad may be the effect on the other less necessary organs; so it is that one who worries himself into an attack of indigestion is really preparing for an emergency by sacrificing the less essential for the more essential activities. The practical difficulty in this is that the worry almost always fails to be of use, either because the expected emergency does not arise at all or