So deeply convinced is Professor Stanley Hall of the primitive and fundamental character of the fear instinct, that he refers to the facts that “if the cerebrum is removed, animals, as Goltz and Bechterev have proved, manifest very intense symptoms of fear, and so do human monsters born without brains, of hemicephalic children, as Sternberg and Lotzko have demonstrated.”
The fear instinct is of such vital importance that it is found in animals after decerebration, and persists in animals after spino-vago-sympathetic section. Sherrington found the fear instinct present in dogs after section of the spinal cord and also after complete section of the vago-sympathetic nerves, thus removing all sensations coming from the viscera, muscles, and skin, below the shoulder, leaving only the sensations from the front paws, head and cerebral activity. The dog was a sort of cerebral animal. The whole body below the shoulder, skin, muscle, viscera, were all anaesthetic, and yet the fear instinct remained intact.
On the other hand, after complete ablation of the cerebral hemispheres of the dog, so that the animal became spinal, all cerebral functions being totally wiped out, Goltz invariably found that the fear instinct remained unimpaired. The fear instinct is inherent in animal life—existence. As long as there is life, there is fear.
So potent, all embracing, and all pervading is the fear instinct, that the physician must reckon with it in his private office, in the hospital, and in the surgical operating room. In a number of my cases psychognosis, the study and examination of mental states, clearly reveals the fact that even where the neurosis has not originated in a surgical trauma, surgical operations reinforced, developed, and fixed psychopathic conditions.
The fear instinct is one of the most primitive and most fundamental of all instincts. Neither hunger, nor sex, nor maternal instinct, nor social instinct can compare with the potency of the fear instinct, rooted as it is in the conditions of life primordial.
When the instinct of fear is at its height it sweeps before it all other instincts. Nothing can withstand a panic. Functional psychosis in its full development is essentially a panic. A psychogenetic examination of every case of functional psychosis brings one invariably to the basic instinct of life, self preservation and the fear instinct.
As Whittier puts it:
Still behind the tread I hear
Of my life companion, Fear,
Still a shadow, deep and vast