96. Let us now pass to another consideration, namely, whether Consciousness—however interpreted—is legitimately conceived as a factor in the so-called conscious and voluntary actions; or is merely a collateral result of certain organic activities? To answer this, we must first remember that Consciousness is a purely subjective process; although we may believe it to be objectively a neural process, we are nevertheless passing out of the region of Physiology when we speak of Feeling determining Action. Motion may determine Motion; but Feeling can only determine Feeling. Yet we do so speak, and are justified. For thereby we implicitly declare, what Psychology explicitly teaches, namely, that these two widely different aspects, objective and subjective, are but the two faces of one and the same reality. It is thus indifferent whether we say a sensation is a neural process, or a mental process: a molecular change in the nervous system, or a change in Feeling. It is either, and it is both, as I have elsewhere explained.[229] There it was argued that the current hypothesis of a neural process causing the mental process—molecular movement being in some mysterious way transformed into sensation—is not only inconceivable, but altogether unnecessary; whereas the hypothesis that the two aspects of the one phenomenon are simply two different expressions, now in terms of Matter and Motion, and now in terms of Consciousness, is in harmony with all the inductive evidence.
97. “It may be assumed,” says Professor Huxley, “that molecular changes in the brain are the causes of all the states of consciousness of brutes. Is there any evidence that these states of consciousness may conversely cause those molecular changes which give rise to muscular motion? I see no such evidence. The frog walks, hops, swims, and goes through his gymnastic performances, quite as well without consciousness, and consequently without volition, as with it; and if a frog in his natural state possesses anything corresponding with what we call volition, there is no reason to think that it is anything but a concomitant of the molecular changes in the brain, which form part of the series involved in the production of motion. The consciousness of brutes would appear to be related to the mechanism of their body simply as a collateral product of its working, and to be as completely without any power of modifying that working as the steam-whistle which accompanies the work of a locomotive engine is without influence upon its machinery. Their volition, if they have any, is an emotion indicative of physical changes, not a cause of such changes.” Particular attention is called to the passages in italics. In the first is expressed a view which seems not unlike the one I am advocating, but which is contradicted by the second. Let us consider what is implied.
98. When Consciousness is regarded solely under its subjective aspect there is obviously no place for it among material agencies, regarded as objective. So long as we have the material mechanism in view we have nothing but material changes. This applies to the frog, with or without its brain; to man, supposed to be moved by volition, or supposed to move automatically. The introduction of Consciousness is not the introduction of another agent in the series, but of a new aspect; the neural process drops out of sight, the mental process replaces it. The question whether we have any ground for inferring that in the series there is included the particular neural state which subjectively is a state of Consciousness, must be answered according to the evidence. Well, the evidence shows that the actions do involve the co-operation; and this Professor Huxley expresses when he says that the molecular changes in the brain form part of the series involved in the production of motion. Whether we regard the process objectively as a series of molecular changes, or subjectively as a succession of sentient changes, the sum of which is on the one side a motor impulse, on the other a state of consciousness, we must declare Consciousness to be an agent, in the same sense that we declare one change in the organism to be an agent in some other change. The facts are the same, whether we express them in physiological or in psychological terms. The physiologist, having only the material aspect of the organism in view, says, “A cerebral process initiates a motor process”; the psychologist says, “A sensation determines an action.” Unless the two processes have been linked together by an organic disposition, native or acquired, there will be no such motor process following the cerebral process. A dog standing outside the gate is unable to ring the bell, though having seen another dog ring it, he may wish to do so; but the cerebral process (his wish) is not linked on to the needful motor process—he has not learned to realize the wish; whereas the other dog, having by trial hit upon the right mode of directing his muscles, has registered this experience, and can ring the bell. The organized disposition which enables the dog to do this may truly enough be called a modification of the mechanism; but what we have here to note is that a sensation originally determined the movement, and always determines it.
99. It is the unfortunate ambiguity of the word Consciousness, and the questionable hypothesis of the brain being the sole seat of Sensibility, which darken this investigation. Because animals, after the brain has been removed, are seen to perform certain actions as deftly as before, they are said to perform these without the intervention of Consciousness; when all that is proved by the facts is that these actions are performed without the intervention of the brain. In support of this explanation, examples are cited of unconscious actions performed by human beings. But if we assign Sensibility not to one part of the nervous system exclusively, but to the whole, we can readily understand how the loss of a part will be manifested by very marked changes in the reactions of the whole, and yet not altogether prevent the reactions of the parts remaining intact. An animal must respond somewhat differently with and without a brain. One marked difference is the spontaneity of the actions when the brain is intact, and the loss of much spontaneity when the brain is injured or removed. Cerebral processes prompt and regulate actions, as the pressure of the driver on the reins prompts and regulates the movements of the horses; but the carriage is moved by the horses and not by the driver; and the action is executed by the motor mechanism, whether the incitation arise in a cerebral process or a peripheral stimulation.
100. If we admit that Consciousness is itself an organic process, accompanying the molecular changes as a convex surface accompanies a concave, we must also admit that its fluctuations are adjustments and readjustments of the organic mechanism, and that the actions are the effects of these—their resultants. The loss of the brain must obviously cause a great disturbance in these adjustments. We may call that a loss of Consciousness, if we choose to limit the term to one mode of sentient reaction. But this loss of a mode does not change those reactions which persist so as to convert them into purely mechanical reactions. A troop of soldiers may have lost its directing officer, but will fight with the old weapons and the old intelligence, though not with the same convergence of individual efforts. A frog or a pigeon no more acts as well without a brain as with a brain, than the troop of soldiers fights as well without an officer.
101. Having thus claimed a place for Consciousness in the series of organic processes, let us now see whether it has a place among the active agencies. According to Professor Huxley it is not itself an agent, but only the “collateral product of the working of the machine.” It accompanies actions, it does not direct them. It is an index, not a cause.
Surely it seems more accurate to say that it accompanies and directs the working? It accompanies the working in two senses: first, as the subjective aspect of the objective process; secondly, as the change which produces a subsequent change, that is to say, the movements initiated by a feeling are themselves also felt as they pass; and this feeling enters into the general stream of simultaneous excitations out of which new movements and feelings arise; or to express it physiologically, the sensory impressions determine muscular movements, which in turn react on the nerve-centres, and these reactions blend with the general excitation of reflected and re-reflected processes.[230] Since every change in Consciousness is a change in the sentient organism, which objectively is a change in the nervous centres, the working of the mechanism being itself a dependent series of such changes, each movement must have a reflected influence on the general state. This reflected influence may be viewed as a collateral product of the working; but there is no real analogy between it and the whistle of the steam-engine, because this reflected influence demonstrably does intervene in the subsequent movements. The feeling which accompanies or follows a particular movement cannot indeed modify that movement, since that is already set going, or has passed; here there is some analogy to the steam-whistle; but the analogy fails in the subsequent history: no movements whatever of the steam-engine are modified by the whistle which accompanies the working of that engine; yet how the reflected influence modifies the working of the organism! If the hand be passing over a surface, there is, accompanying this movement, a succession of muscular and tactile feelings which may be said to be collateral products. But the feeling which accompanies one muscular contraction is itself the stimulus of the next contraction; if anywhere during the passage the hand comes upon a spot on the surface which is wet or rough, the change in feeling thus produced, although a collateral product of the movement, instantly changes the direction of the hand, suspends or alters the course—that is to say, the collateral product of one movement becomes a directing factor in the succeeding movement. Now this is precisely what no automaton can effect, unless for changes that are prearranged. A steam-engine drives its locomotive over the rails, be they smooth or rough, entire or broken; it whistles as it goes, but no whistling directs and redirects its path.
102. Volition is said to be an “emotion indicative of physical changes, not a cause of such changes.” Here it is necessary to understand in what sense the term cause is employed. I should prefer stating the proposition thus: a volition is a state of the sentient organism, indicative of physical changes which have taken place, and of changes which will take place. Because it is the expression of the first group of changes, it cannot be their origin; but it can be, and is the origin of the second group, which it initiates. The indignation excited by an insult or a blow is not the origin of the emotion or the pain, but it is the origin of the actions which are prompted by this sentient state. In fact no sooner do we admit that the organism is a sentient mechanism, than the conclusion is irresistible that Sensibility is a factor in the working of that mechanism.
103. “Much ingenious argument,” says Professor Huxley, “has at various times been bestowed upon the question: How is it possible to imagine that volition which is a state of consciousness, and as such has not the slightest community of nature with matter and motion, can act upon the moving matter of which the body is composed, as it is assumed to do in voluntary acts? But if, as is here suggested, the voluntary acts of brutes—or in other words, the acts which they desire to perform—are as purely mechanical as the rest of their actions, and are simply accompanied by the state of consciousness called volition, the inquiry, so far as they are concerned, becomes superfluous. Their volitions do not enter into the chain of causation of their actions at all.... As consciousness is brought into existence only as the consequence of molecular motion in the brain, it follows that it is an indirect product of material changes. The soul stands related to the body as the bell of a clock to the works, and consciousness answers to the sound which the bell gives out when it is struck.” This has been answered in the foregoing pages; nor do I think the reader who has recognized the ambiguity of the term Consciousness, and the desirability of replacing it in this discussion by the less equivocal term Sentience, will need more to be said.
104. The important question whether reflex actions are insentient, and therefore mechanical, will occupy us in the next problem. The question of Automatism which has been argued in the preceding chapters, may, I think, be summarily disposed of by a reference to the irresistible evidence each man carries in his own consciousness that his actions are frequently—even if not always—determined by feelings. He is quite certain that he is not an automaton, and that his feelings are not simply collateral products of his actions, without the power of modifying and originating them. Now this fundamental fact cannot be displaced by any theoretical explanation of its factors. Nor would this fundamental truth be rendered doubtful, even supposing we were to grant to the full all that is adduced as evidence that some actions were the result of purely mechanical processes without sentience at all. I am a conscious organism, even if it be true that I sometimes act unconsciously. I am not a machine, even if it be true that I sometimes act mechanically.