78. Descartes having attributed all animal actions to a sensitive mechanism, and indeed all human actions to a similar mechanism, endeavored to reconcile this hypothesis with the irresistible facts of Consciousness—which assured us that our actions, at least, were determined by Feeling. To this end he assumed that man had a spiritual principle over and above the sentient principle. The operation of this principle was, however, limited to Thought; the actions themselves were all performed by the automatic mechanism; so that, in strict logic, the conclusion from his premises was the same for man as for animals. This conclusion Professor Huxley announced in his Address before the British Association, 1874222—to the great scandal of the general public, which did not understand him aright; and to the scandal also of a physiological public, which, strangely enough, failed to see that it was the legitimate expression of one of their favorite theories—the celebrated Reflex Theory. Now although it is quite open to any one to reject the premises which lead to such a conclusion, if he sees greater evidence against the conclusion than for the premises, it is surely irrational to accept the premises as those of scientific induction, and yet reject the conclusion because it endangers the stability of other opinions? For my own part,441 I do not accept the premises, and my polemic will have reference to them.
79. Professor Huxley adopts certain Theses which represent the views generally adopted by physiologists; to which he adds a Thesis which is adopted by few, and which he only puts forward hypothetically. Against these positions I place Antitheses, less generally adopted, but which in my belief approximate more nearly to the inductions of experience.
Theses. Antitheses.
I. There can be no sensation without consciousness. I. There is sensation without consciousness, if consciousness means a special mode of Sentience.
II. There can be no consciousness without the co-operation of the brain. II. The co-operation of the brain is only necessary for a special mode of Sentience; other modes are active when the brain is inactive.
III. Sensation and Consciousness are in some inexplicable way caused by molecular changes in the brain, following upon these as one event follows another, the causal link between motion and sensation being a mystery. III. Unless the molecular changes be limited to the brain as the occasional cause, there is no following of sensation or motion, no causal link between the two; but the neural process is the sensation, viewed objectively, the sensation is the neural process, viewed subjectively. In this antithesis, Neural Process is not limited to the brain, but comprises the whole sensitive organism as the efficient cause.
IV. All actions which take place unconsciously are reflex, and reflex actions are the operation of an insentient mechanism; they are therefore as purely mechanical as those of automata. IV. All actions are the actions of a reflex mechanism, and all are sentient, even when unconscious; they are therefore never purely mechanical, but always organical.
V. The animal body is a reflex mechanism; even when the brain co-operates with the other centres, and produces consciousness, this product is not an agent in determining action, it is a collateral result of the operation. V. Sentience being necessary to reflex action, it is necessarily an agent.
442 80. The first four Theses are those current in our textbooks, so that it is only the fifth which will have the air of a paradox. Nor, as a paradox, is it without advocates. Schiff long ago suggested it hypothetically. Hermann mentions it as entertained by physiologists, whom he does not name.223 Laycock, and, if I remember rightly, Dr. Drysdale, have insisted on it; and Mr. Spalding has proclaimed it with iterated emphasis. Of the Antitheses nothing need be said here, since the whole of this volume is meant to furnish their evidence.
I have already stated that my polemic is against the views that Professor Huxley is supposed to hold by those whom his expressions mislead, rather than against the views I imagine him really to hold. I have little doubt that he would disavow much that I am forced to combat, although his language is naturally interpreted in that sense. But I do not know in how far he would agree with me, and in the following remarks I shall confine myself to what seems to be the plain interpretation of his words, since that is the interpretation which has been generally adopted, and which I most earnestly desire to refute.
81. To begin with this passage. After stating the views of Descartes, he says: “As actions of a certain degree of complexity are brought about by mere mechanism, why may not actions of still greater complexity be the result of a more refined mechanism? What proof is there that brutes are other than a superior race of marionnettes, which eat without pleasure, cry without pain, desire nothing, know nothing, and only simulate intelligence as a bee simulates a mathematician?” What proof? Why, in the first place, the proof which is implied in the “more refined mechanism” required for the greater complexity443 of actions. In the next place, the proof that the organism of the brute is very different from the mechanism of a marionnette, and is so much more like the organism of man, that since we know man to eat with pleasure and cry with pain, there is a strong presumption that the brute eats and cries with somewhat similar feelings.
82. Having stated the hypothesis, Professor Huxley says he is not disposed to accept it, though he thinks it cannot be refuted. His chief reason for not accepting it is that the law of continuity forbids the supposition of any complex phenomenon suddenly appearing; the community between animals and men is too close for us to admit that Consciousness could appear in man without having its beginnings in animals. Finding that animals have brains, he justly concludes that they also must have brain functions; and they also therefore must be credited with Consciousness. This argument seems to me to have irresistible cogency; and to be destructive not only of the automaton hypothesis, but equally of the hypothesis on which the Reflex Theory is founded. If the law of continuity forbids the sudden appearance of Consciousness, the law of similarity of property with similarity of structure forbids the supposition that central nerve-tissue in one part of the system can suddenly assume a totally different property in another part. If the brain of an animal, a bird, a reptile, or a fish—and a fortiori if the ?sophageal ganglia of an insect or a mollusc—may be credited with Sensibility, because of the fundamental similarity of these structures with the structures of the human brain, then surely the spinal cord must be credited with Sensibility; for the tissue of the spinal cord is more like that of the brain, than the brain of a reptile is like the brain of a man. The sudden disappearance of all Sensibility, on the removal of one portion of the central nervous system, would be a violation of the law of continuity.444 And if it be said that Consciousness is not the same as Sensibility, but is a specially evolved function of a specially developed organ, the answer will be that this is only a difference of mode, and that the existence of Sensibility is that which renders the automaton and reflex theories untenable.
83. Professor Huxley would probably admit this; for however his language may at times seem to point to another conclusion, and is so far ambiguous, he has expressed the view here maintained with tolerable distinctness in the following passage, to which particular attention is called:—
“But though we may see reason to disagree with Descartes’ hypothesis, that brutes are unconscious machines, it does not follow that he was wrong in regarding them as automata. They may be more or less conscious sensitive automata; and the view that they are such conscious machines is that which is implicitly or explicitly adopted by most persons. When we speak of the actions of the lower animals being guided by instinct and not by reason, what we really mean is that though they feel as we do, yet their actions are the results of their physical organization. We believe, in short, that they are machines, one part of which (the nervous system) not only sets the rest in motion and co-ordinates its movements in relation with changes in surrounding bodies, but is provided with a special apparatus the function of which is the calling into existence of those states of consciousness which are termed sensations, emotions, and ideas.”
84. To say that they are “conscious automata” seems granting all that I demand; but there are two objectionable positions which the phrase conceals: first, that Consciousness is not a coefficient; and secondly, that Reflex Action is purely mechanical.
Professor Huxley nowhere, I think, establishes the distinction445 between Consciousness as a term for a special mode of Feeling, and Consciousness as the all-embracing term for sentient phenomena. His language always implies that an action performed unconsciously is performed mechanically; which may be acceptable if by unconsciously be meant insentiently. I hold that whether consciously or unconsciously performed, the action is equally vital and sentient. In the case he has cited of a soldier now living who is subject to periodic alternations of normal and abnormal states, in the latter states all the actions being said to be “unconscious,” we have only to read the account to recognize ample evidence of Sentience. Here is a descriptive passage:—
85. “His [the soldier’s in the abnormal state] movements remain free, and his expression calm, except for a contraction of the brow, an incessant movement of the eyeballs, and a chewing motion of the jaws. The eyes are wide open, and their pupils dilated. If the man happens to be in a place to which he is accustomed he walks about as usual; but if he is in a new place, or if obstacles are intentionally placed in his way, he stumbles against them, stops, and then feeling over the objects with his hands, passes on one side of them. He offers no resistance to any change of direction which may be impressed upon him, or to the forcible acceleration or retardation of his movements. He eats, drinks, smokes, walks about, dresses and undresses himself, rises and goes to bed at the accustomed hours. Nevertheless pins may be run into his body, or strong electric shocks sent through it, without causing the least indication of pain; no odorous substance, pleasant or unpleasant, makes the least impression; he eats and drinks with avidity whatever is offered, and takes asaf?tida or vinegar of quinine as readily as water; no noise affects him; and light influences him only under certain conditions.”
446 There is no one of these phenomena that is unfamiliar to students of mental disease. The case is chiefly remarkable from the periodicity of the recurrence of the abnormal state. I have collected other cases of the kind, and may hereafter find a fitting occasion to quote them.224 The an?sthesia and “unconsciousness” noted, no more prove the actions performed by this soldier to have been purely mechanical, i. e. undetermined by sensation, than an?sthesia and unconsciousness prove somnambulists and madmen to be machines. In the pathological state called “ecstasy” there is a considerable diminution of sensibility to external stimuli; with a concentration on certain feelings, images, trains of thought, exhibiting itself in expressions of emotion. “Les malades,” says a master, “paraissent entièrement absorbés par leurs mouvements intérieurs, ils refusent généralement de manger, et spécialement la volonté de l’ame semble complètement enchainée.”225
86. Observe that while this soldier exhibits such insensibility to certain stimuli, he unequivocally exhibits sensibility to other stimuli. All his acts show sense-guidance. Sight and Touch obviously regulate his movements. And when he feels objects placed in his way, and then passes beside them, wherein does this differ from the normal procedure of sensitive organisms? wherein does it resemble automata? Dr. Mesmet—from whose narrative the case is cited—remarks that the sense of Touch seems to persist “and indeed to be more acute and delicate than in the normal state”; upon which Professor Huxley has this comment:—“Here a difficulty arises. It is clear from the facts detailed that the nervous apparatus447 by which in the normal state sensations of touch are excited is that by which external influences determine the movements of the body in the abnormal state. But does the state of consciousness, which we term a tactile sensation, accompany the operation of this nervous apparatus in the abnormal state? or is consciousness utterly absent, the man being reduced to a pure mechanism? It is impossible to obtain direct evidence in favor of the one conclusion or the other; all that can be said is that the case of the frog shows that the man may be devoid of any kind of consciousness.”
87. It is here we are made vividly aware of the absolute need there is to disengage the terms employed from their common ambiguities. All the evidence of a tactile sensation which can possibly be furnished, on the objective side, is furnished by the actions of this soldier; to doubt it would be to throw a doubt on the sensibility of any animal unable to tell us what it felt; nay, even a man if he were dumb, or spoke a language we could not understand, could give us no other proof. We conclude that the soldier had tactile sensations, because we see him guided by them as we ourselves are guided by tactile sensations; we know that he is an organism, not a machine, and therefore reject the inference that he has become reduced to a “pure mechanism” because it is inferred that his consciousness is absent. And on what is this inference grounded? 1°, The belief that the brain is the sole organ of consciousness (Sentience)—a belief flatly disproved by the facts, which show Sentience when the brain has been removed; and 2°, the belief that the decapitated frog, because it avoids obstacles and redirects its leaps to avoid them, does so without Sentience. According to the definition we adopt, we may either say that the decapitated frog, and the soldier in his abnormal state, act without consciousness, or with it. But what does not seem permissible448 is to deny that their actions exhibit the clearest evidence of sense-guidance, and the kind of volition which this sense-guidance implies; and this is quite enough to separate them from actions of automata. When a man ducks his head to avoid a stone which he sees falling towards him, he assuredly has a sensation, i. e. there is a grouping of neural elements, which subjectively is a sensation, and this originates a grouping of other neural elements, the outcome of which is a muscular movement, which subjectively is a motor sensation: this grouping would not have been originated unless the particular grouping had preceded it; nor would the simple retinal stimulus have excited this sensation unless the nerve-centres had been attuned to such response by many previous experiences: the ignorant child would not duck its head on seeing the stone approach. In our familiar use of the word Consciousness it would be correct to say that the man ducks his head “unconsciously”; and yet expressing the fact in psychological language, we also say: He ducks his head because remembering the pain of former similar experiences, he knows that if the stone strikes him he will again be hurt as before, therefore he wills to avoid it; expressing it in physiological language we may say: The man acts thus because he is so organized that a particular neural process is the stimulus of a particular central discharge; and he became thus organized through a long series of anterior adjustments responding to stimuli, each adjustment being the activity of the vital organism.
88. There can be no doubt that the soldier had perceptions, and that these perceptions guided his movements; whether these shall be called “states of consciousness” or not, is a question of terms. Now since we know that certain actions are uniformly consequent on certain perceptions, we are justified in inferring that whenever the449 actions are performed, the perceptions preceded them: this inference may be erroneous, but in the absence of positive evidence to the contrary it is that which claims our first assent. Is it evidence to the contrary that the perception may have stimulated the action, yet been unaccompanied by the special mode named consciousness? Not in the least. We learn to read with conscious effort; each letter has to be apprehended separately, its form distinguished from all other forms, its value as a sign definitely fixed, yet how very rarely are we “conscious” of the letters when we read a book? Each letter is perceived; and yet this process passes so rapidly and smoothly, that unless there be some defect in a letter, or the word be misspelled, we are not “conscious” of the perceptions. Are we therefore reading automata?226
We are said to walk unconsciously at times; and the continuance of the movement is said to be due to reflex action. But it is demonstrable that the cutaneous sensibility of the soles of the feet is a primary condition. If the skin be insensible, the walking becomes a stumble. In learning to walk, or dance, the child fixes his eyes on his feet, as he fixes them on his fingers in learning to play the piano. After a while these registered sensations connected with the muscular sense suffice to guide his feet or his fingers; but not if feet or fingers lose their sensibility.
89. With these explanations let us follow the further details of this soldier’s abnormal actions:—
450 “The man is insensible to sensory impressions made through the ear, the nose, the tongue, and, to a great extent, the eye; nor is he susceptible to pain from causes operating during his abnormal state. Nevertheless it is possible so to act upon his tactile apparatus as to give rise to those molecular changes in his sensorium which are ordinarily the causes of associated trains of ideas. I give a striking example of this process in Dr. Mesmet’s words: ‘Il se promenait dans le jardin, on lui remet sa canne qu’il avait laissé tomber. Il la palpe, promène à plusieurs reprises la main sur la poignée coudée de sa canne—devient attentif—semble prêter l’oreille—et tout à coup appelle, “Henri! les voilà!” Et alors portant la main derrière son dos comme pour prendre une cartouche, il fait le mouvement de charger son arme, se couche dans l’herbe à plat ventre dans la position d’un tirailleur, et suit avec l’arme épaulée tous les mouvements de l’ennemi qu’il croit voir à courte distance.’ In a subsequent abnormal period Dr. Mesmet caused the patient to repeat this scene by placing him in the same conditions. Now in this case the question arises whether the series of actions constituting this singular pantomime was accompanied by the ordinary states of consciousness, the appropriate trains of ideas, or not? Did the man dream that he was skirmishing? or was he in the condition of one of Vaucanson’s automata—a mechanism worked by molecular changes in the nervous system? The analogy of the frog shows that the latter assumption is perfectly justifiable.”
90. Before criticising this conclusion let me adduce other illustrations of this dreamlike activity. “A gentleman whom I attended in a state of perfect apoplexy,” says Abercrombie, “was frequently observed to adjust his nightcap with the utmost care when it got into an uncomfortable state: first pulling it down over his eyes, and451 then turning up the front of it in the most exact manner.” According to the current teaching, these actions, which seem like evidence of sensation, are nothing of the kind, because—the patient was “unconscious”; that is to say, because he did not exhibit one complex kind of Sensibility, it is denied that he exhibited another kind! he did not feel discomfort, nor feel the movements by which it was rectified—because he could not speak, discuss impersonal questions, nor attend to what was said to him! Abercrombie cites other cases: “A gentleman who was lying in a state of perfect insensibility from disease of the brain” (note the phrase, which really only expresses the fact that external stimuli did not create their normal reactions) “was frequently observed even the day before his death to take down a repeating watch from a little bag at the head of his bed, put it close to his ear and make it strike the hour, and then replace it in the bag with the greatest precision. Another whom I saw in a state of profound apoplexy, from which he recovered, had a perfect recollection of what took place during the attack, and mentioned many things which had been said in his hearing when he was supposed to be in a state of perfect unconsciousness.” Dr. Wigan also tells of a lady whom he knew, and who was actually put in a coffin, under the belief that she was dead when in a trance. Her sense of hearing was then preternaturally acute. In her second-floor bedroom she heard what the servants said in her kitchen. When her brother came to see her and he declared she should not be buried until putrefactio............