They are afraid without knowing why, perhaps even without knowing that they are afraid, while man, with his highly developed consciousness, has a perfect knowledge of his fear. Both man and the brute have in the same degree love of life, dislike of death, and fear in the face of danger. But the notion in the animal is so vague and indistinct that it hardly exists; it is translated by acts the significance of which escapes the actor himself, while in man the same idea becomes precise, reasoned out, and conscious. What we call the instinct for self-preservation is only one of the forms of fear. A violent and irresistible emotion takes possession of our whole being when we perceive ourselves in the face of death, and is the manifestation of a love of life and dread of death that every man bears within himself. It requires real courage to do violence to this general and deep instinct.
We have, therefore, the following progression: The animal, by a simple reflex movement, reacts to excitations that threaten its life; and this reflex movement is admirably adapted to the necessities of its existence.
Next the reflex movement becomes more and more complicated, into a movement of the whole—with flight, outcry, and tremor.
Then, as the animal becomes more and more intelligent, emotion accompanies the action, till the animal not only responds to the menacing excitations by a movement of flight, but has also a conscious feeling of fear.
Finally, a superior degree of perfection appears in man. Besides the act and the emotion, intelligence is displayed, and the man comprehends why he is afraid.
The study of the reactions of the animal shows to what point all the instinctive movements provoked by fright are exactly conformed to the necessity of living, which Nature imposes upon each of her children. When a danger comes which it is necessary to escape, every animal has two means of deliverance. It can flee precipitately, or it can hide and keep still. I believe that the paralyzing and stupefying action of fear, which is manifested in man as well as in the animal, is a salutary instinct, which is probably transmitted from the animal to man, and which, if it is not useful to man, is evidently quite so to the animal. The reaction of immobility is so complete with some animals as to simulate death. There are various insects which, when they are touched, feign to be dead. Every animal has its special kind of reaction. The butterfly flutters in capricious détours; the turtle withdraws into its shell; the bee, surprised by an enemy, stings him; the cuttle-fish empties its ink-bag; the hedgehog rolls himself up into a ball; other animals utter piercing cries. These are all reactions that represent different means of defense.
In studying the causes of fear, it is well to lay aside all rational and reasoned causes. When we know that our life is threatened, our
