of the physical struggle for self-preservation through the motor mechanism and an inhibition of the function of the leading organs that do not participate-the non-combatants, so to speak. Fear arose from injury, and is one of the oldest and surely the strongest emotion. By the slow process of vast empyricism nature evolved the wonderful defensive motor mechanism of many animals and of man. Now the stimulation of this mechanism leading to a physical struggle is action, and the stimulation of this mechanism without action is emotion.

We may say that fear is a phylogenetic fight or flight. On this hypothesis all the organs and parts of the entire animal are integrated, connected up or correlated, for self-preservation by activity of its motor mechanism. We fear not in our hearts alone, not in our brain alone, not in our viscera alone; fear influences every organ and tissue-each organ or tissue is stimulated or inhibited according to its use or hindrance in the physical struggle for existence. In thus concentrating all or most of the nerve force on the nerve muscular mechanism for defense alone, a greater physical power is developed. Hence, it is that animals under the stimulus of fear are able to perform preternatural feats of strength. Then, too, for the same reason the exhaustion following fear will be the greater, as the powerful stimulus of fear drains the cup of nervous energy, though no visible action may result. An animal under the stimulus of fear may be likened to an automobile with the clutch thrown out but whose engine is racing at top speed. The gasoline is being consumed, the machinery is being worn, but the machine as a whole does not move, though the power of its engine may cause it to tremble.

Applying this conception to human beings of today certain mysterious phenomena are at once elucidated. It must be borne in mind that man has not been presented with any new organs to meet the requirements of his present state of civilization-indeed not only does he possess the same type of organs as his savage fellows but also the same type of organs possessed by even the lower animals. In fact the present status of civilization of man is now operated with the primary equipment of brutish organs. Perhaps the most

striking difference is the greater control man has gained over his primitive instinctive reactions. Contrasted with the entire duration of organic evolution, man has come down from his arboreal abode and assumed his new rôle of increased domination over the physical world but a moment ago. And now, though sitting at his

FIG. 2. Note the resemblance between the facial expression in the great efforts of the athlete and the expression of the strong emotions. The relation of motion and emotion becomes more obvious as strong motor and emotional acts are compared. From "Outing."

desk in command of a complicated machinery of civilization, when he fears a business catastrophe it is in the terms of his ancestral physical battle in the struggle for existence. He cannot fear intellectually, he cannot fear dispassionately, he fears with all of his

organs, and the same organs are stimulated and the same organs are inhibited as if instead of its being a battle of credit, of position or of honor, it were a physical battle with teeth and claws. Whether the cause of acute fear is moral, financial, social, or stage fright, the heart beats wildly, the respirations are accelerated, perspiration is increased, there is a pallor, trembling, indigestion, dry mouth, etc. The phenomena are those of physical exertion in self defense or escape. There is not one group of phenomena for the acute fear of the president of a bank in a financial crash and another for the hitherto trusted official who suddenly and unexpectedly faces the naked probability of the penitentiary; or one for a patient who unexpectedly finds he has a cancer and another for the hunter when he shoots his first big game. Nature has but one means of response and whatever the cause the phenomena are always the same-always physical.

The stimulus of fear if repeated from day to day, whether it be a mother anxious on account of the illness of a child; a business man struggling against failure; a politician under contest for appointment; a broker in the daily hazard of his fortune; litigants in legal battle, or a jealous lover who fears a rival,-the countless real as well as baseless fears in daily life-all forms of fear as it seems to me, express themselves in similar terms of ancestral physical contest and on this law dominate the various organs and parts of the body. Anger and fear express opposite states. Fear expresses the evidence of a strong desire to escape from danger; anger, a strong desire to attack physically and vanquish opposition. This hypothesis is strongly supported by the outward expression of fear and anger. When the business man is conducting a struggle for existence against his rivals and when the contest is at its height, he may clench his fists, pound the table, perhaps show his teeth and he may exhibit every expression of physical combat. Fixing the jaw and showing the teeth in anger merely emphasizes the remarkable tenacity of phylogeny. Although the development of the wonderful efficiency of the hands has led to a modification of the once powerful canines of our progenitors, the ancestral use of the teeth for attack and defense is attested in the display of anger. In all sta

tions of life differences of opinion may lead to argument and argument to physical combats, even to the point of killing. Physical violence of the savage and the brute still lies surprisingly near the surface.

There have now been presented some of the reasons based largely on gross animal behavior why fear is to be regarded as a

FIG. 3. The attitude and the facial expression represent anger, and the integration of the entire body for a strong aggressive action shows the extent to which the body of man has been evolved as a motor mechanism. From "Outing."

response to phylogenetic association of physical danger. I shall now present some additional evidence in support of this hypothesis from the clinical and the experimental side. Although there is not convincing proof yet there is evidence that the effect of the stimulus of fear upon the body without physical activity is more injurious than actual physical contest which results only in fatigue without gross physical injury. It is well known that the soldier lying under

fire waiting in vain for orders to charge suffers more than the soldier that flings himself into the fray; that a wild animal in an open chase against capture suffers less than when cowering in captivity. An unexpressed slumbering emotion is measurably relieved by action. It is probable that the various energizing substances needful in physical combat such as the secretion of the thyroid, the adrenals, etc., but which are not consumed in action may, if frequently repeated, cause physical injury to the body. That the brain is definitely influenced, even damaged by fear has been proved by the following experiments:

Rabbits were frightened by a dog but not injured, and not chased. After various periods of time the animals were killed and their brain cells compared with the normal. Widespread changes were seen. The principal clinical phenomena expressed by the rabbit were rapid heart, accelerated respiration, prostration, tremors, and a rise in temperature.

The dog showed similar phenomena-excepting instead of muscular relaxation as in the rabbit the dog showed aggressive muscular action. Both the dog and the rabbit were exhausted and although the dog exerted himself actively and the rabbit remained physically passive, the rabbit was much more exhausted.

Further observations were made upon the brain of a fox chased for two hours by members of a hunt club, then finally overtaken by the hounds and killed. The brain cells of this fox as compared with those of a normal fox showed extensive physical changes in most of the cells.

The next line of evidence is offered with some reservation but it has seemed to me to be more than mere idle speculation. It relates to the phenomena of one of the most interesting diseases in the entire category of human ailments-I refer to exophthalmic goiter or Graves' Disease—a disease primarily involving the emotions. This disease is frequently the direct sequence of severe mental shocks or a long and intensely worrying strain. The following case is typical. A broker was in his usual health up to the panic of 1907. During this panic his fortune and that of others was for almost a year in jeopardy, failure finally occurring. During this