CHAPTER X.

SENSUOUS APPETITE AND MOVEMENT.

Sensuous Appetency. -- In our classification of mental activities we have marked off as standing in strongest opposition to the cognitive operations of the mind the class of states embracing appetites, desires, impulses, volitions, emotions, and the like. There is no accepted English term which accurately expresses what is common to them all. The designation active powers, employed by Reid and Stewart, ought obviously to include the intellect. Orectic faculty -- the literal transcription of the Aristotelian term -- is too unfamiliar. Hamilton gave currency to the epithet conative, which emphasizes the idea of effort prominent in some of these acts; whilst others prefer the title appetitive faculty. These two last names seem to us on the whole exposed to fewest objections; however, it should be borne in mind that the phenomena of appetency include not only states of yearning for absent pleasures, but also the enjoyment of gratifications attained.

Appetite. -- The term appetite was used in a very wide sense by mediaeval writers to denote all forms of internal inclination, comprehending alike the natural tendencies or affinities (appetites naturalis) of plants and inorganic substances, which impel them towards what is suitable to their nature, and the feelings of conscious attraction (appetitus elicitus) in sentient and rational beings. The formal object of the appetitive faculty in this broad signification is the good. Under the good is comprised, not merely the pleasant, but everything in any fashion convenient to the nature of the being thus attracted. Continued existence, felicity, development, and perfection, together with whatever is apparently conducive to these ends, are all in so far good, and consequently a possible object of appetency; whilst whatever is repugnant to them is a mode of evil, and therefore a ground for aversion or the negative activity of the same faculty.

Of conscious appetite the schoolmen recognized two kinds as essentially distinct -- rational and sensitive. The former has its source in intellectual, the latter in sensuous, apprehension. The two faculties, however, do not act in isolation; desires and impulses in the main sensuous often embody intellectual elements, and we therefore deem it best to postpone the chief portion of our treatment of appetency to Part II. of the present book.

The scholastics also divided conative states into appetitus concupiscibiles and appetitus irascibiles. The appetitive side of the soul was investigated by mediaeval writers mainly from the standpoint of Ethics or Moral Theology. The modern branch of study known as AEsthetics, the analysis of the mental states aroused by the contemplation of the beautiful and the sublime, and the dissection of our emotions, which take up so much room in psychological treatises of the present day found little or no space in their speculations.

Modern writers commonly confine the term appetite to certain organic cravings. These arise from the physical condition of the body; they are mainly of a periodically recurrent character, and they are essential to the preservation of the individual or the species. The chief forms usually enumerated are those of hunger, thirst, sleep, exercise, and sex. All these activities are of the lower order of mental life, and have their source in sensation. Thus hunger springs from the uneasy feelings of the alimentary canal arising from privation of the nutriment on which its appropriate functions are exercised. The craving for sleep or physical activity is similarly awakened by fatigue or the consciousness of an accumulation of surplus energy. Besides these peculiarly organic appetites there are tendencies in all sentient beings towards objects and actions in harmony with their nature or some part of it. The appropriate satisfaction of such inclinations commonly awakens pleasure, whilst excess or defect causes pain, and thus brings into play two great protective agencies which guard the life of the individual and the race. The gregarious instinct, maternal affection, feelings of anger, jealousy, and fear, may also belong to the purely sensuous order of conscious life provided they contain no element of reflective activity, and it is in this form they are exhibited by lower animals.

Movement. -- Appetency expresses itself in motion. The tree pushes out its roots and opens its leaves in search of nutriment. The animal stirred up by feeling, creeps, walks, runs, swims, or flies in pursuit of its food. And man, too, is constantly moving one or other of his limbs, or organs, to gratify some need or desire. In later life, the instant a volition is exerted, the appropriate movement or chain of movements necessary for its satisfaction follows with precision. Yet this has not been always so. We know that our skill in handwriting, cricket, or skating, is the outcome of many unsuccessful efforts; and we have only to watch a child of eighteen months toddling from one chair to another to realize that even our most natural movements have been very gradually acquired.

Voluntary movement analyzed. -- If we analyze any complex deliberate action of mature life, such as tying our shoe-lace, putting a book on a shelf, or trying to hit a ball at tennis or at cricket, we shall discover that several distinct elements are involved. First, a visual image of the contemplated act, its extent, direction, and velocity, is formed. Accompanying this, especially if the operation be unusual, there is a motor representation, a faint imaginary rehearsal of the movement, in which there is an estimate taken of the quantity and quality of muscular effort to be employed. Finally there is, at least in volitional acts, the fiat, or act of the will, that discharges the motor energy into the selected channels causing the imagined action to be realized. The Will, of course, does not consciously pick out the particular muscles to be exerted. It is only late in life that the mind learns the existence of such muscles. But past experience has revealed to us different kinds of muscular feelings, and the will selects which of these shall be re-exerted. The entire consciousness arising out of volitional effort and muscular strain has been called the feeling of innervation, and there is much dispute as to its nature. Whatever be its physiological accompaniments and the ingredients of which it is composed, it is by controlling and varying this innervation under the guidance of incoming sensations muscular, tactual, and visual, that the direction, range, and rapidity of the movement is determined. But how is this intelligent control of motor energy evolved? How does the infant come to be able to select, not the right muscles, of which it may never know anything, but the right muscular feelings to be stirred up in order to accomplish a particular complex operation? This is the question of the development of the power of locomotion. In order to answer it we must distinguish several kinds of movements.

Automatic movements. -- In the first place we find that all living animal organisms perform certain vital actions, independently of stinmlation from without. The pulsations of the heart and the circulation of the blood are perhaps the best illustrations of this class of movements. They are called automatic. They are the unconscious outcome of the living mechanism.

Reflex action. -- There is another class of actions which differ from the former in that they are occasioned by peripheral stimulation. These are movements in response to sensory impressions without the intervention of any conscious effort -- the involuntary reflexion of an afferent impulse back along an efferent nerve, e.g., winking, sneezing, swallowing. (See p. 46.) Such movements are styled reflex; but they often gradually fade into the other groups, especially in acquired habits. Original reflex actions are unlearned and involuntary, though they may sometimes become subject to the will, as in the act of coughing.

Impulsive action. -- Yet another class of movements are apparently common to man with all the lower animals from birth. They differ from automatic movements in their irregularity, and from reflex action in seeming to he occasioned not by external stimulation, but by internal feelings. They are impulsive actions, and chiefly out of these voluntary movements are developed.

Origin of voluntary movement. -- How then are the first impulsive acts of the infant converted into the freely directed complex operations of later life? Broadly speaking, two theories prevail among modern psychologists. Primitive impulsive action is of two kinds -- random and instinctive. One theory derives all voluntary action from the former, the other insists on the important part played by the latter combined with reflex movements.

Theory of random action. -- Dr. Bain insists upon the existence of a fund of spontaneity in the infant organism. There are exhibited, he urges, in children and young animals a quantity of movements of an aimless character. Apart from external stimulation and reflex action, when fresh and healthy the young animal exerts its limbs, and frisks and gambols in a purposeless manner. The living engine, in fact, generates a surplus of motor power, which tends to relieve itself in action of any kind. This is the source of the play-impulse. Under the so-called "Law of Self-conservation," formulated in the statement that pleasure is accompanied with heightened energy, and pain with lowered energy, this original haphazard action assumes definite lines. Amongst the fortuitous movements some result in a pleasant experience, and in consequence of the heightened energy tend to sustain themselves, whilst painful actions, by the consequent lowering of activity, become suppressed, "as when an animal moving up to a fire encounters the scalding heat with its depressing (sic) influence, and therefore has its locomotion suspended."^{1} By repetition the lucky movements become associated with the pleasure attained, and after a time the mere idea of this pleasure is able by force of this association to excite the appropriate action to obtain it. When this stage is reached we have, according to Dr. Bain, free voluntary control.

Objections to the theory. -- Opponents object: (1) That both the statement and application by Bain of the alleged Law are untenable. Whilst pleasure commonly awakens desire for a renewal or continuance of an act, it often tones down general vitality. Pains, on the other hand, augment activity. Punishment is a universally recognized means of stirring up energy; whilst intense pleasures are frequently exhausting. (2) Even granting the Law, as expounded by Dr. Bain, the fortuitous pleasant and painful experiences arising out of random action would be far too few to account for the rapidity of acquisition, and for the complex character of many of the acts of very early life both in animals and children. (3) Further, instinct, it is urged, is proved to be as primordial a phenomenon as random action, and if admitted to be a vera causa of complex movements in the lower animals, it is unscientific to reject it as an explanation of similar acts in man. (4) To us the most serious error is the identification of voluntary -- i.e., freely willed movement -- with impulsive action merely moulded into a definite shape by the strongest pleasure. Complex movements of a well-trained dog are in this view the type of voluntary action.^{2}

Theory of instinctive action. -- The opposite school insist much on reflex action, and, since evolution and the doctrine of heredity have become popular, still more on instinct as contributing the chief materials towards the voluntary movements of later life. Amongst the impulsive actions both of the lower animals and of the human infant are to be found, they urge, a multitude of movements which exhibit a striking uniformity or regularity throughout the species. They involve greater complexity than in the case of merely reflex action. They manifest an unconsciously purposive character. Finally, they are "unlearned," or at least so rapidly acquired when the organism is sufficiently mature as to be justly considered innate habits. These constitute instinctive actions properly so called. Thus ducklings, on leaving the nest, take to the water and swim; young swallows fly, and chickens, just out of the shell, peck at insects with perfect accuracy. Similarly, young pigs just born trot about, and calves and lambs scramble to their legs after a few failures, and find their mother's udder.^{3} To the human infant potentially endowed with reason, and designed to be reared and instructed by intelligent parents, fewer definite instincts are allotted by nature than to the young animal, and nearly all these which he receives need a longer time to develop. Still, recently more exact and scientific observation of children has, it is maintained, established a sufficient quantity of instinctive action to account for the growth of voluntary complex movement.

The most complex operation in the power of the infant possessed at birth is the act of sucking. In addition to this there are enumerated as instinctive movements, though some of them require from three to twelve months to manifest themselves, the actions of grasping and pointing at objects, of carrying objects to the mouth, of biting and chewing, of crying and smiling, of turning the head aside with a frown, of holding the head erect, of sitting up, of standing, of creeping, and of walking. For many of these the appropriate muscles and nerve-centres need time to mature, but when this period has arrived, it is maintained, that the impulse to creep, stand, or walk, shows itself with striking suddenness, and the new aptitude is often perfected with a rapidity quite incompatible with the associationist theory of fortuitous successes.

Imitation. -- The instinct to utter sounds is present from the beginning, but the impulse to imitate sounds, as well as other actions, appears later, and often quite abruptly. The instinct of imitation, which exhibits itself in smiling, frowning, laughing, and other gestures, in the dramatic impulse, and the make-believe games of childhood, in the force of fashion, and in the contagion of enthusiasm and panic, is one of the greatest educative forces in human life. These various forms of instinctive movement, it is argued, account sufficiently for man's acquisition of a complete command over his power of movement without appealing to the hypothesis of random action.^{4}

Growth of control of movement. Probable theory. -- It seems to us that the arguments adduced in support of the latter view prove the insufficiency of the "random" theory. The fact that all men walk upright is the outcome not of fortuitous action in all directions, but of an instinctive impulse hereditary in the human race. Yet such evidence does not exclude the agencies of pleasure and pain, nor the effect of casual or undesigned experience in developing our powers to perform definite movements, as is indeed fully admitted by the leading advocates of Instinct. Voluntary action is freely desired action. But desire implies a striving towards a known good, towards a preconceived end. Voluntary movement therefore pre-supposes a representation of the movement, or of its separate parts, not merely in terms of visual, but of motor sensation. In order to pronounce a word, or to swim, it is not enough to be able to imagine the sound of the word, or the picture of a man swimming, we must be acquainted with the muscular feelings involved in such actions, and these must necessarily, on their first occurrence, have been not anticipated.

The child, subject to obscure feelings and cravings, seeks relief in movements, some of a purely haphazard, others of a vaguely purposive, or instinctive character. Part of these actions turn out pleasant, whether accidentally or because they satisfy an instinct, matters not; part of them result in pain. Whatever be the true expression of Dr. Bain's Law of self-conservation, and whatever be the real effect of pleasure and pain on general vitality, there is indisputably a tendency in the living organism to prolong and repeat movements which afford satisfaction, and to check those which prove disagreeable. The infant rejoices to reiterate the same sound, and the same movement of its arm or leg again and again. With each successive repetition the force of association between the muscular feeling and the pleasant result increases, and each tends more and more to suggest the other.^{5} However, the motor feeling is less easily pictured by the imagination, and much less interesting in itself than the agreeable result. Accordingly its force in consciousness diminishes, and after a time the wish for the effect results in the performance of the action without any advertence to the muscular feelings.

The earliest motor exertions will, of course, be very simple, and the connexion between action and the pleasing effect immediate. The child touches a smooth object, and finds the experience agreeable; or he utters a cry, and rejoices in the discovery of his power of noise. Later on his vague tentative efforts will result in the combination of two or more actions, and, encouraged by his successes, he will gradually come to perform more and more complex operations, to conceive more distant ends, and to be incited by the anticipation of more remote results. As Professor Dewey remarks: "The infant begins with a very simple and immediate idea. His first efforts are limited to movements containing very few elements, and the end of which is directly present. The consciousness of an end which is remote, and which can be reached only by the systematic regulation of a large number of acts, cannot be formed until the combination of motor impulses has realized some such end."^{6}

Voluntary Action. -- Freedom, however, means more than complexity. So long as we merely have feeling tending to issue into action, even though that action be complex and towards a pre-conceived object, we have not voluntary action strictly so called.^{7} Under the influence of such unreflecting desires the somnambulist, and in simpler cases the lower animals, perform elaborate operations which are nevertheless involuntary, not free. In the earlier years of childhood all action is, of this kind, completely determined by feelings and temperament. But later on, as experience extends and intellect is developed, conflicting motives and rival courses of possible action emerge into consciousness. The child finds himself able to inhibit particular impulses. The power of reflexion awakens within him, and he becomes aware that he can choose or decide which of the impulsive tendencies he will approve, which of the competing desires within him he will adopt and identify with himself.^{8} When this stage is reached, we have voluntary action in the true sense. But it should not be forgotten that in such voluntary action the physical movement is really carried out by the mechanism of the organism working substantially in the same manner as in purely impulsivn or automatic action, save in so far as the discharge of physical energy is initiated or modified by volition. Bodily movement is, in the language of the schoolmen, actus imperatus, not actus elicitus -- action commanded or sanctioned, but not actually exerted by the will.

A kindred treatment of this subject is thus summarized by Professor Ladd: "The voluntary movements of the body presuppose the impulsive, and yet they reach far back into the obscurity of the earlier development of consciousness. Strictly speaking, they imply the presence in consciousness of two or more different or conflicting ideas of motion, one of which rather than the others is realized as a sequence of an act of conscious choice. They imply then a considerable development of the activities of ideation and volition. Moreover, those movements, which are ordinarily called voluntary, are really so only with respect to certain of the elements; they also contain elements which must be classed as reflex, centrally coordinated, and impulsive. The term 'voluntary' fitly lays the emphasis upon the conscious act of choice; and this in turn implies ideas of various possible forms of bodily motion gained by previous experience with the correlated states of conscious feeling and conditions of the body as giving rise to or modifying these states."^{9}

We may therefore classify movements according to their origin, their voluntariness, and their conscious or unconscious character thus: 8 Lotze accurately observes: "An action is 'voluntary' in case interior initial state (impulse) from which a motion would originate as a result does not merely take place, but is approbated, or adopted or endorsed, by the will. Every action is 'involuntary' which mechanically ccnsidered issues from the same initial point, and wholly in the same manner, hut without having experienced such approbation." (Outlines of Psychology, p. 87.)

Secondary Automatic action or Acquired Reflexes. -- Voluntary actions, at first painfully learned, may now through frequent repetition cease to require any conscious effort for their performance, or at least for their continuation. They thus become assimilated to reflex or automatic action. The child learning to play the piano has at first to make a separate volitional effort to apprehend each note and to press each key. Next, each movement suggests its successor without any separate effort. Later on, even the intervening sensory impressions drop out of consciousness; and the process has passed into the condition of reflex action. Nay, he may come to be able to play at sight a piece in which his fingers execute extremely rapid combinations of movements in response to the visual impressions of the notes, whilst his attention is distracted by other thoughts. The tendency of repetition to convert volitional into reflex action is one of the most important agencies in the economy of our nature. The whole effect of education depends upon it, and our entire life is an illustration of it. In walking, speaking, reading, writing, in the various accomplishments, games, handicrafts, in by far the greater part of the operations of our daily life, from making our toilet in the morning to undressing at night, we are ever performing inadvertently complex operations, involving the delicate coordination of many muscles, which at first were accomplished with difficulty and perhaps after many unsuccessful efforts. From the similarity of these mechanical modes of action to unconscious vital movements and sensori-motor actions they have been styled secondarily automatic, and also acquired reflex actions.

Ideo-motor action. -- Not only can movement be initiated by volitional effort, by sensory impressions and by associated movements; it can also he excited by the mere idea of the action itself. Though advocated as a modern discovery, this truth was not unfamiliar to the schoolmen.^{10} We have seen that in the deliberate performance of a movement we first form a representation of that movement. Now it is a matter of common experience that in proportion as the image -- especially the motor image -- becomes more lively, it tends of its own accord without any effort of will to pass into reality. Vivid ideas tend to realize themselves. The physiological explanation suggested is that the same nerve-centres which are engaged in the actual sensation or movement are also the seat of the representation, but excited in a feebler manner. The thought of past sea-sickness awakened by the peculiar smell of the ship's cabin has sometimes realized itself before the ship has left the harbour. The sight of an object on the floor moves an absent-minded man to stoop and pick it up. Most of the movements in reverie, dreaming, somnambulism, and the hypnotic state, are the outcome of motor ideas. The overpowering force of the vivid idea of falling down from a precipice or high building has probably been the cause of many seemingly deliberate suicides. The temptation sometimes awakened by express prohibitions and the fascination exerted by great crimes, and by the horrible, or the disgusting, is similarly explained by the absorbing force of a vividly suggested idea.

Expectectant attention. -- Intense anticipation causes us to rehearse in imagination the movements as well as the sensations to which we look forward. Some at least of the phenomena of "thought-reading" are thus explained. The "subject" endeavouring to "will" or intently realize the word or the action unconsciously guides the hand of the "reader," or in some other way gives external expression to the idea absorbing his mind. Mono-manias are often due to the "possession" or "obsession" of the mind by some fixed idea" which, arising perhaps out of a morbid condition of the brain, inhibits the corrective influence of other intellectual acts and suspends volitional control. The patient is often aware of the folly or the wickedness of the insane impulse, yet feels unable to extinguish the craving to carry out the suggestion.

Here, as in the case of sensori-motor action, the facility of the transition from the mental state to the physical act increases with repetition; and in familiar acts the passage from the idea to its realization is so easy and smooth that some psychologists have made it a ground for denying that voluntary or appetitive activity is ultimately distinct from cognition. It is quite true that the will very frequently effects its object indirectly by increasing the strength of an idea through attention until this idea prevails over all other ideas in the field of consciousness and then realizes itself in movement. But the striving, the tension in appetency is different in kind from the activity of cognition; and the flat or veto which consents to or rejects a solicitation is quite distinct in nature from mere increase or diminution attention to the thought as a thought.

The question how an unextended volition can move a material limb brings us in face of a final inexplicability. That the soul is endowed with a locomotive faculty is simply an ultimate fact. Our life-long experience assures us that mind and body do interact, but How we cannot tell.

Readings. -- On Appetite, cf. St. Thomas, Sum. i. q. 80; Suarez, De Anima, Lib. V. cc. 1-4; Joseph Rickaby, Moral Philosophy, Pt. I c. iv. ; Farges, Le Cerveau et l'Ame, pp. 404-411; Dr. Stöckl Lehrbuch d. Phil. §§ 18-20. On Movement, Farges, op. cit. pp. 233-273; Mercier, Psychologie, pp. 264-280; Pesch, Institutiones Psychologicae, §§ 667-671; Dr. Gutberlet, Die Psychologie, Pt. I. c. iii; Ladd, op. cit. pp. 526-531; Carpenter, Mental Physiology, pp. 17-23, 70-80, 100-107.

{1} Mental Science, p. 80.

{2} See Martineau, A Study of Religion, Vol. II. pp. 206-224; Sidgwick, Methods of Ethics, Bk. II. c. v. § 4.

{3} For a fuller treatment of this subject see the section on Instinct in the supplementary chapter on Comparative Psychology.

{4} See James, Vol. II. pp. 403, ff.; Bain, Emotions and Will, II. c. i.; Preyer, The Mind of the Child, Part I. cc. xi. xii.; Baldwin, Emotions and Will, c. xiii.; Höffding, pp. 308-312.

{5} As suggestion acts in the order of the original experience, it has been objected that an agreeable effect cannot suggest the action which caused it. But the original tendency to reiteration solves the difficulty. Thus, suppose an impulse (a) finds vent in a motor feeling (b) an agreeable experience (c) auditory. tactual, gustatory, or visual. If the process is repeated in succession a few times (as when an infant cries la, la, la) we have (a) (b) (c) (a) (b) (c) &c., in which, at every repetition, the agreeable effect (c), precedes (a), and so tends in the future to suggest it. That is, the representation of the pleasant effect will excite the impulse which will in turn awaken the motor feeling, and so on, until a new presentation intervenes, and inhibits the process. The tendency to repetition may be due physiologically to the facility of adhering to a nervous path once opened, or to the lively sensibility and unstable condition of nerve-centres recently excited. Cf. Martineau, Vol. II. pp. 208, 209; and James, Vol. II. pp. 582-592.

{6} Psychology, 3rd Edit. p. 381.

{7} That is in the modern sense -- deliberate or free action.

{9} Elements of Physiological Psychology, p. 528.

{10} See Père Coconnier, L'Hypnotisme Franc, p. 346.