Fear Page #8

THE learned and eloquent Professor of Physiology at Turin has given us in the book which he has entitled “Fear,” an analysis of this mental condition and its accompanying physical states, which, marked as it is by scientific accuracy and couched in charming and even in poetical diction, will take high rank as a popular exposition of our knowledge of the expression of one of the most interesting of the emotions of both men and animals.

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Let us now see what happens when the master is not at home, or what an animal does when its head is cut off, and only the spinal cord is left. We shall see here, too, that the more liberty the master gives to the maid, the more arrogant she grows, at last lording it over the master himself.

A decapitated frog does not die immediately; it may move for days, and if deprived of the brain only remains alive for some time.

We will consider the more usual case, namely, that of a frog of which the head has been completely cut off with a pair of scissors. The animal shivers and writhes for a few moments, then it stops, and would remain motionless if it were kept under a glass cover in a damp atmosphere, where nothing would irritate the skin. But if we touch its leg or put a drop of vinegar upon it, the animal tries at once to escape and to remove the disturbing agent from the surface of its body. If we put a drop of vinegar on the left leg it tries to wipe it off with the right, and vice versa. But if we cut off one of the legs or bind it fast, and then put a drop of vinegar on the other leg which is at liberty, the frog makes use of this same leg to rub away the drop.

At first sight this seems to be an act of intelligence. It may be maintained that it is done by choice, but we cannot say that this activity requires the guidance of the intelligence. A dog of which the spinal cord has been severed and a sleeping man make the same movements.

Neither must it be thought that these movements are only to be found in frogs and the lower animals. We shall see that in man also they perform all the most indispensable vital functions without the co-operation of the brain. Fontana, one of the most celebrated Italian physiologists, discovered, as early as the middle of the last century, that one could decapitate rabbits and guinea-pigs without causing their immediate death. And he also found that if care were taken by previously binding the most important arteries; so that the animal should not lose too much blood, and if the respiration were sustained artificially by means of bellows, it could live for some time, and show itself sensitive to external stimuli.[6]

[6] Fontana: Veleno della Vipera, i. p. 317.

IV

If we could hear the soliloquies of the man who is writing a book, many, I think, would renounce for ever the pleasure of setting the printing press in motion. It would be a curious experience, if one could read between the lines the tale of discouragement, uncertainty, trouble, and know the repeated struggles by which some difficulty was overcome, a passage was composed, a clause or a sentence written. In scientific works it would be seen that the most frequent interruptions and exclamations arise always from doubt, and the anxiety which torments an author of not making his meaning clear.

There is no remedy. He who wishes to explain a scientific subject in a clear and simple way must stop from time to time; he must come out of himself and take his reader’s place, forget all he knows in order to listen impartially to his own voice, and to judge if what he has said may be easily understood. And this I shall do, but the reader must not be repulsed by the first difficulties: our first steps cost the greatest effort. In order to comprehend the physical nature of man, and to know how this exquisite machinery of ours works, we must first examine attentively some of the most important organs which are constantly at work in our nervous system. It is in science as in the study of languages, one must first learn the meaning of the most indispensable words in order to understand what is said to us in the foreign tongue.

Till the beginning of this century very confused notions prevailed as to the activity of the brain and spinal cord. Luigi Rolando, the celebrated physiologist of the University of Turin, was the first who clearly showed that the medulla oblongata (that part of the spinal cord which lies nearest the brain) must be regarded as the centre of the whole nervous system. No one in his time knew the structure of the nerve-centres better than he, and it was he who proved that the medulla oblongata 'is the first rudiment of the nervous system, the seat of physical sensibility, of instinct, the director of voluntary movements, the centre of life, and the wonderful cause of most surprising phenomena known under the names of sympathies and consents.’[7]

[7] L. Rolando, Saggio sopra la vera struttura del cervello e sopra le funzioni del sistema nervoso, Sec. III. p. 140. Turin, 1828.

If one cuts the head of a duck off at a blow, it does not remain motionless but moves, flaps its wings and flutters along, as though it meant to make its escape. It is said that the Emperor Commodus caused the heads of the ostriches in the circus to be shot off with curved arrows, and that the birds still ran on till they reached the goal. If we cut the head of a dog off with a hatchet, we see that the trunk wags the tail. There is a curious irony in the fact, but it need not shock us, for the animal no longer feels. If an irritant is applied to the skin, it draws its tail between its legs as though it were afraid, although it is headless.

V

A difficult question confronts us here. There are some physiologists who maintain that the maid is blind, and that she performs her work without knowing what she does; that she pulls the cord when the bell rings, heats the stoves, cooks, cleans the utensils, sweeps the house, gives the rubbish to the dustman, and so on--but all this without power of discernment, acting like an automaton, unable to make the slightest change in what she does merely from habit. Others, again, maintain that she does possess a few fragments of intelligence, that at certain times she reasons too, and that the soul of the house does not dwell in the master alone.

It is a very difficult question; because, if it can be proved that the maid is blind and does everything from habit, one may also say that the master--poor man!--does not see much either, and that he has certainly not been able to teach the maid anything.

I say the question is difficult also because the names of the greatest living physiologists are connected with it. Goltz and Foster took a frog, destroyed its brain, and then plunged it into a vessel full of water. If the frog were then touched it might be seen, like other frogs in similar circumstances, to respond by swimming about and even jumping out of the vessel. The water was then warmed up to 40°. The frog remained motionless, nor did it feel that the water was growing hot; it did not try to leap out, and thus allowed the heat to increase until it was boiled without making any movement which might indicate sensation. Therefore the spinal cord alone cannot think. The frog moves like a machine whenever it feels those stimuli to which it is accustomed (like an automaton of which one must press a certain knob in order to produce a particular movement); it is indifferent to everything else, allowing itself to be burnt and boiled and never moving, because no pain is felt.
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