61. Much of what has been said in the preceding chapter respecting the passive side of the organism is equally applicable to the active side. Our actions are classed as voluntary and involuntary mainly in reference to their being consciously or unconsciously performed; but not wholly so, for there are many involuntary actions of which we are distinctly conscious, and many voluntary actions of which we are at times sub-conscious and unconscious. I do not propose here to open the long and arduous discussion as to what constitutes Volition, my present purpose being simply that of fixing the meaning of terms, so that the question of Automatism may not be complicated by their ambiguities. “Voluntary” and “involuntary” are, like “conscious” and “unconscious,” correlative terms; but commonly, instead of being understood as indicating differences of degree in phenomena of the same order, they are supposed to indicate differences of kind—a new agent, the Will, being understood in the one case to direct the Mechanism which suffices without direction in the other. 62. This interpretation is unphysiological and unpsychological, since it overlooks the fact that both voluntary and involuntary actions belong to the same order of phenomena, i. e. those of the sentient organism. Both involve the same efficient cause, i. e. co-operant conditions. We draw a line of demarcation between the two abstractions—as416 between all abstractions—but the concrete processes they symbolize have no such demarcation. Just as the thought which at one moment passes unconsciously, at another consciously, is in itself the same thought, and the same neural process; so the action which at one moment is voluntary, and at another involuntary, is itself the same action, performed by the same mechanism. The incitation which precedes, and the feeling which accompanies the action, belong to the accessory mechanisms, and may be replaced by other incitations and other feelings; as the fall of an apple is the same event, involving the same conditions, i. e. efficient cause, whether the occasional cause be a gust of wind or the gardener’s scissors, and whether the fall be seen and heard or not. I may utter words intentionally and consciously, and I may utter the same words automatically, unconsciously; I may wink voluntarily, and wink involuntarily. There are terms to express these differences; but they do not express a difference in the efficient agencies.
63. Many writers seem to think that the involuntary actions belong to the physical mechanical order, because they are not stimulated by cerebral incitations, and cannot be regulated or controlled by such incitations—or as the psychologists would say, because Consciousness in the form of Will is no agent prompting and regulating such actions. But I think this untenable. The actions cannot belong to the mechanical order so long as they are the actions of a vital mechanism, and so long as we admit the broad distinction between organisms and anorganisms. Whether they have the special character of Consciousness or not, they have the general character of sentient actions, being those of a sentient mechanism. And this becomes the more evident when we consider the gradations of the phenomena. Many, if not all, of those actions which are417 classed under the involuntary were originally of the voluntary class—either in the individual or his ancestors; but having become permanently organized dispositions—the pathways of stimulation and reaction having been definitely established—they have lost that volitional element (of hesitation and choice) which implies regulation and control. But even here a slight change in the habitual conditions will introduce a disturbance in the process which may awaken Consciousness, and the sense of effort, sometimes even causing control. An instinctive or an automatic action may be thus changed, or arrested. Take as an example one of the unequivocally automatic actions, that of Breathing. It is called automatic because, like the actions of an automaton, it is performed by a definitely constructed mechanism, always working in the same way when stimulated and left to itself. There must of course be a sense of effort in every impulse which has resistance to overcome, organs to be moved; but the mechanism of Breathing is so delicately adjusted, that the sense of effort is reduced to a minimum, and we are unconscious of it, or sub-conscious of it. Nevertheless, without altering the rate or amplitude of the inspirations and expirations, we become distinctly conscious of them, and, moreover, within certain limits we can control them, so that the Breathing passes from the involuntary to the voluntary class.
64. Pass on to other examples. What action can be more involuntary than the rhythmic movements of the heart and the contractions of the iris? Compared with the actions of the tongue or limbs, these seem riveted by an iron necessity, freed from all consciousness and control. Yet the movements of the heart are not only stimulated by sensations and thoughts, they are also capable of being felt; and the movements both of heart and iris are not wholly removed from our control. That we do418 not habitually control (that is, interfere with) the action of the heart, the contraction of the iris, or the activity of a gland, is true; it is on this account that such actions are called involuntary; they obey the immediate stimulus. But it is an error to assert that these actions cannot be controlled, that they are altogether beyond the interference of other centres, and cannot by any effort of ours be modified. It is an error to suppose these actions are essentially distinguished from the voluntary movement of the hands. We have acquired a power of definite direction in the movements of the hands, which renders them obedient to our will; but this acquisition has been of slow laborious growth. If we were asked to use our toes as we use our fingers—to grasp, paint, sew, or write with them, we should find it not less impossible to control the movements of the toes in these directions, than to contract the iris, or cause a burst of perspiration to break forth. Certain movements of the toes are possible to us; but unless the loss of our fingers has made it necessary that we should use our toes in complicated and slowly acquired movements, we can do no more with them than the young infant can do with his fingers. Yet men and women have written, sewed, and painted with their toes. All that is requisite is that certain links should be established between sensations and movements; by continual practice these links are established; and what is impossible to the majority of men, becomes easy to the individual who has acquired this power. This same power can be acquired over what are called the organic actions; nevertheless the habitual needs of life do not tend towards such acquisition, and without some strong current setting in that direction, or some peculiarity of organization rendering it easy, it is never acquired. In ordinary circumstances the number of those who can write with their toes is extremely rare, the urgent419 necessity which would create such a power being rare; and rare also are the examples of those who have any control over the movement of the iris, or the action of a gland; but both rarities exist.
It would be difficult to choose a more striking example of reflex action than the contraction of the iris of the eye under the stimulus of light;214 and to ordinary men, having no link established which would guide them, it is utterly impossible to close the iris by any effort. It would be not less impossible to the hungry child to get on the chair and reach the food on the table, until that child had learned how to do so. Yet there are men who have learned how to contract the iris. The celebrated Fontana had this power; which is possessed also by a medical man now living at Kilmarnock—Dr. Paxton—a fact authenticated by no less a person than Dr. Allen Thomson.215 Dr. Paxton can contract or expand the iris at will, without changing the position of his eye, and without an effort of adaptation to distance.
To move the ears is impossible to most men. Yet some do it with ease, and all could learn to do it. Some men have learned to “ruminate” their food; others to vomit with ease; and some are said to have the power of perspiring at will.216 Now, if once we recognize a link of sensation and motion, we recognize a possible source of control; and if the daily needs of life were such that to fulfil some purpose the action of the heart required control, we should learn to control it. Some men have, without such needs, learned how to control it. The eminent physiologist, E. F. Weber of Leipzig, found that420 he could completely check the beating of his heart. By suspending his breath and violently contracting his chest, he could retard the pulsations; and after three or five beats, unaccompanied by any of the usual sounds, it was completely still. On one occasion he carried the experiment too far, and fell into a syncope. Cheyne, in the last century, recorded the case of a patient of his own who could at will suspend the beating of his pulse, and always fainted when he did so.
65. It thus appears that even the actions which most distinctly bear the character recognized as involuntary—uncontrollable—are only so because the ordinary processes of life furnish no necessity for their control. We do not learn to control them, though we could do so, to some extent; nor do we learn to control the motions of our ears, although we could do so. And while it appears that the involuntary actions can become voluntary, it is familiar to all that the voluntary actions tend, by constant repetition, to become involuntary. Thus involuntary actions, under certain limitations, may be controlled; on the other hand, the voluntary are incapable of being controlled under the urgency of direct stimulation. Both are reflexes.
Inasmuch as almost all actions are the products of stimulated nerve-centres, it is obvious that these actions are reflex—reflected from those centres. It matters not whether I wink because a sensation of dryness, or because an idea of danger, causes the eyelid to close: the act is equally reflex. The nerve-centre which supplies the eyelid with its nerve has been stimulated; the stimuli may be various, the act is uniform. At one time the stimulus is a sensation of dryness, at another an idea of danger, at another the idea of communicating by means of a wink with some one present; in each case the stimulus is reflected in a muscular contraction. Sensations421 excite other sensations; ideas excite other ideas; and one of these ideas may issue in an action of control. But the restraining power is limited, and cannot resist a certain degree of urgency in the original stimulus. I can, for a time, restrain the act of winking, in spite of the sensation of dryness; but the reflex which sets going this restraining action will only last a few seconds; after which, the urgency of the external stimulus is stronger than that of the reflex feeling—the sensation of dryness is more imperious than the idea of resistance—and the eyelid drops.
If a knife be brought near the arm of a man who has little confidence in the friendly intentions of him that holds it, he shrinks, and the shrinking is “involuntary,” i. e. in spite of his will. Let him have confidence, and he does not shrink, even when the knife touches his skin. The idea of danger is not excited in the second case, or if excited, is at once banished by another idea. Yet this very man, who can thus repress the involuntary shrinking when the knife approaches his arm, cannot repress the involuntary winking when the same friend approaches a finger to his eye. In vain he prepares himself to resist that reflex action; in vain he resolves to resist the impulse; no sooner does the finger approach, than down flashes the eyelid. Many men, and most women, would be equally unable to resist shrinking on the approach of a knife: the association of the idea of danger with the knife would bear down any previous resolution not to shrink. It is from this cause that timorous women tremble at the approach of firearms. An association is established in their minds which no idea is powerful enough to loosen. You may assure them the gun is not loaded; “that makes very little difference,” said a na?ve old lady to a friend of mine. They tremble, as the child trembles when he sees you put on the mask. These illustrations422 show that the urgency of any one idea may, like the urgency of a sensation, bear down the resistance offered by some other idea; as the previous illustrations showed that an idea could restrain or control the action which a sensation or idea would otherwise have produced. According to the doctrines current, the Will is said to be operative when an idea determines an action; and yet all would agree that the winking which was involuntary when the idea of danger determined it, was voluntary when the idea of communicating with an accomplice in some mystification determined it.
66. There is no real and essential distinction between voluntary and involuntary actions. They all spring from Sensibility. They are all determined by feeling. It is convenient, for common purposes, to designate some actions as voluntary; but this is merely a convenience; no psychological nor physiological insight is gained by it; an analysis of the process discloses no element in a voluntary action which is not to be found in an involuntary action—except in the origin or degree of stimula............