vision, is made by Dr. Ireland in Journal of Alent. Sci., January, 1893, pp.
CHAPTER XVI.
Summary: Final Statement of Habit and Accommodation.
§ I. Stimmary of Theory of Development} After the foregoing detailed statements of the facts of development, and the solution of certain particular genetic problems, we may come to a general synthesis. What is the least that we can say about an organism's develop- ment.'* Everybody admits that two things must be said: first, it develops by getting habits formed; and second, it develops by getting new adaptations which involve the breaking up or modification of habits — this latter being called accoi}nnodatio7is.
The law of habit may now be stated generally in some such way as this: Habit is the tejtdency of an organism to continue more and more readily processes which ai^e vitally beneficial.
This principle we have found an axiom in biology and psychology. In psychology great instances of it are readily cited — instinct, emotional expression, the perform- ance of movements pictured in the attention, even atten- tion itself. In order to habit, it has become evident, the 1 This section is not intended as a resume of the book and should not be considered so, but only of those points which are needed for the remaining sections of this chapter.
Suuiniary of Theory of Dcvelop77icnt. 477 organism must have contractility — ability to make a re- sponse in movement to a stimulus — and then it must have some incentive to make and keep making the 7'igJit kind of movcnicnt. The essential thing about habit, then, is this: tJie maintenance of advantageous stimulations by the oiganisnt s own movements. Now what is the incentive to the right kind of movement? This question carries us farther.
Three answers are possible. The only incentive may be the actual stimulus, altogether outside the organism, and the right movement may be only a chance selection from many random movements. This is the ordinary biological theory. The stimulus is supposed to ' come along ' very often, and, moreover, to be very varied in its kind, locality, etc.; so that by repeating happy chance movements, habits are formed, and by compounding the habits, these habits become complex and varied. So the creature develops. On this view development is entirely an expression of the one principle of Nervous Habit.
The second answer says: the incentive is in part, as before, outside the organism, that is, the external stimulus must remain constant; but the organism, after the first reaction to the stimulus, tends to repeat its lucky reactions again. This is the psychological theory. It finds in this tendency to repeat lucky movements the nervous analogue of pleasure, and makes it with the principle of excess discha7ge, following upon pleasure, the additional thing. There is thus an internal organic 'incentive.' By this the creature 'goes out,' and secures its own repetitions or avoidances, but only after lucky chance adaptations. This I have designated — in the only form in which it has been held — the Spencer-Bain theory.
47^ Habit and Accommodatio7i.
But this latter theory, superior as it is to the purely biological or * repetition ' view of the biologists, has had in its statement a radical defect, the intimations of Darwin — who nowhere, to my knowledge, fully expresses an opinion — alone excepted. It has held, in Spencer and Bain, that the pleasure or pain process is a reflex of the reacting movement. This, I have argued above in detail, cannot be the case; for movements themselves reflect pleasure or pain only as they serve as stimuli, reproduce stimuli, or arc associated with stimuli. On the contrary, the stimuli as suck are the agents of good or ill, pleasure or pain; and this pleasure or pain process — index, as it is, of the fun- damental vital processes — dictates the very first adapted move7nent tozvard or away from certain kinds of stinuda- tions. This is the third answer and the valid one. Other- wise the principle of excess — as in the form of the ' height- ened nervous wave' of Spencer — only serves to confirm in habits the lucky adaptations already hit upon.
How shall we further conceive the process whereby, from many movements thus generally adapted, some are selected as special adaptations, or particular motor functions.^ This, it is clear, is the question of Accommodation. It occurs by means of excess reactions. It is opposed to Habit in two ways: first, it has reference to new movements, — a pro- spective reference, — while habit has reference always to movements more or less old, a retrospective reference, — and so it runs ahead of habit; and second, it tends, by the selection of new movements, to come into direct conflict with old habitual movements, and so to disintegrate habits. Let us look, then, at accommodation also more closely, gathering up what has gone before in earlier chapters.
In general formula: Accommodation is tJie principle by Summary of Theory of Development. 479 ivJiicJi an organism comes to adapt itself to more complex con- ditions of stimulation by perfoi'ming more complex functions} Various functions have been shown in what proceeds to illustrate this principle; all functions which the individual has leai'ned. Learning to act is just accommodation, noth- ing more nor less. Speech, tracery, handwriting, piano- playing, all motor acquisitions, are what accommodation is, i.e., adaptations to more complex conditions. The common thing about them all is evident from the fore- going statement of the requirements of development: the 7naintenance of stiinnlus by the excessive motor discharge which it stirs up. This is Imitation. In brief, any reaction whatever, no matter how produced, — by accident, by sug- gestion, by obedience, by volition, by effort, under stress of pain or excitement of pleasure, — any reaction by which a useful stimulus is hailed back and enjoyed, or a dam- aging one fled from and escaped, — any such is a case of accommodation, and falls under the theory of imitation now expounded.
But continued accommodation is possible only because the other principle, Jiabit^ all the time conserves the past and gives points d'apptn in solidified structure for new accommodations. Inasmuch, further, as the copy becomes, by transference from the world to the mind, capable of in- ternal revival, in memory, accommodation takes on a new character — a conscious, subjective character — in Volition. Volition arises as a phenomenon of 'persistent imitative suggestion,' as I have argued. That is, volition arises when a copy remembered vibrates with other copies re- membered or presented, and when all the connections, in 1 Compare with these statements of Habit and Accommodation, those given 480 Habit and Acconimodatio7i.
thought and action, of all of them, are together set in mo- tion incipiently. The residue of motive is connected with what we call attention, and the final co-ordination of all the motor elements involved, is volition, or choice. The phys- ical basis of memory, association, thought, is, therefore, that of will also — the cerebrum, — and pathological cases show clearly that aboulia is fundamentally a defect of syn- thesis in perception and memory, arising from one or more breaks in the copy system whose rise I have sketched in what precedes.
§ 2. htteraction of Hahit and Accommodation.
We have seen — to proceed farther on our way — that there is one type of reaction, and only one, to which these two principles have a common application: reactions whose issue tends to remstate the very stinudus whicJi started the reaction. Accommodation is there, in such a reaction, since the advantageous stimulation stands a better chance of repetition if the organism tends thus to get it; but since this repeated stimulus again stimulates to action, and action again follows — there also is habit. So accommo- dation, by the very reaction which accommodates, hands over its gains immediately to the rule of habit. And this is the universal rule.
How true, as a fact, this form of adaptation is! A fact often noticed, always admired, never explained — that organisms move toward the source of light and heat and colour! How can an organism get such a splendid property — that of being so modified by what is good for it, that it itself responds in a way to get it again, and, then, by thus getting it again, makes its future enjoyments Organ ic Cc^itralizatioii. 481 of it sure and easy? This I have given theories to ex- plain: by the law of * Excess ' the stimulus is got again, and by the law of * Sensori-motor association ' the process is fixed in easy habit.
The interaction of these two principles, Accommodation and Habit, — Excess and Association, — gives rise to a two-fold factor in every organic activity of whatever kind. In organisms of any development — where a nervous sys- tem, say, is present, — the environment being a changing one, every structure, with its function, represents a habit which is being constantly modified by the law of accommo- dation. But these modifications themselves, as we have seen, provide again for their own habituation; so there is a constant erosion, and a constant accretion, to the net attainment of the organism. And each function can be understood only in the light of both the influences which have contributed to it. Impulse, for example, is two-fold; instinct is two-fold; attention is two-fold; emotion is two- fold. Is not this a reconciliation in principle of the opposed theories of these functions, one saying that these great organic habits came only by composition, and the other that they came only by selection, intelligent or organic t § 3- Organic Centralization, We have now seen how great habits are formed. Heredity further fixes them, and at the same time renders them more prominent, i.e., as instincts, by erasing the evidences of their origin, and abbreviating the phylo- genetic process in the growth of the individual. I use the phrase 'organic centralization' to denote this great out- come of development, — the differentiation of functions 482 Habit and Accommodation.
by lines of adaptation which run apart, as far as their par- ticular offices and structural products are concerned, but which are yet centralized. For they are centralized when considered together, as constituting, in unity and plan, the common life of the organism. When considered each for itself also, as a well-knit whole of many co-ordinated units, the same centralization is shown about a smaller centre; such as the movements involved in a particular instinct, or the series of movements of the facial muscles in an * expression.' There would possibly be no need for further exposition of this point, since it is a corollary from the general theory already sketched, were it not that it has certain applications.
There are two such applications which are new, I think, and which serve to gather into one point of view conflict- ing opinions regarding two of the most refractory facts in current psychology. I refer to the question of the exist- ence of special nerves for pleasure and pain, or either; and to the attention.
The question arises: If accommodation is secured by a special form of reaction called 'excess,' what relation does this reaction itself sustain to the principle of habit? Does the excess function itself also become centralized? Does it tend to become a separate co-ordinated function, as other motor discharges do } It is to be expected that, in as far as the environment in which an organism lives is constant, any accommodation reaction would, taken for itself, tend to become a habit. As far as the presumption goes, we would expect to find two great kinds of reaction implicated with pleasure and pain. The pain reaction would tend to withdraw the organism from the stimulus which gives pain; and the pleasure reaction would tend to bring the organism into closer relation with the stimulus which gives pleasure. These two kinds of reaction would be possible for any muscular group whatever, and all that would then be required would be some sense organ which would distin- guish between the conditions of stimulation which regu- larly give pleasure — reacting to them with the forward moving reaction, — and those which regularly give pain — reacting to them with the withdrawing movement. This is directly confirmed by the views of Meynert, Richet, Miinsterberg, and Bain, as far as the character of the movements is concerned; and by the results of Dessoir and Goldscheider, as to the differentiation of the sense of pain. It then becomes a matter of indifference whether actual pain nerves are found or not, in connection with any particular function. That depends upon what the race conditions of stimulation have actually been. If the pain stimulus has been regular and peculiar enough, possibly it has got itself a special apparatus; research must decide. But if not, then not. This latter, the negative, is probably the case with pleasure. The stimulus to pleasant function is so general and normal, that pleasure has not become well * centralized ' either in the organism, or, as is very plain, in consciousness. Yet in the special case in which a function has been perpetual, important, and uniform, there we do find pleasure as acute and definitely localized as pain is, i.e., in the sexual function, as Nichols has pointed out. It is not at all improbable that this function has a pleasure nerve apparatus. So it is possible and probable that pain is both a sensation, and a quale or ' tone' of other sensations, emotions, etc.; a sensation, — if it has developed its own apparatus by reacting to definite, well-localized 484 Habit and Accomfnodation.
pain-giving stimulations constantly enough; a quale, — be- cause the organism is never completely balanced in its environment, and the stimulations representing misad- justment and pain are not all constant. So the accommo- dation function of pain, in connection with all possible stimulations, must go on just the same whether there be a sensation pain or not; especially in the sphere of thought, sentiment, and the attentive life, since this is the latest, most complex, and least uniform kind of accommodation.
On the physical side, too, the matter is clear. The excess process at the basis of pleasure and pain, finds channels of outflow which serve over and over again for the reaction required to repeat the pleasure, or stop the pain. The same connection thus serving for many in- stances, becomes well-worn and habitual; and so a connec- tion is formed — a circuit — for pleasure or pain, like the ordinary sensori-motor circuits. If light, for example, con- sidered as constant stimulation, serves to develop, for its different intensities, an organ — the eye, — and certain nerves, which react only to it, as hmiinoits; why can it not also develop, in connection with certain of its intensities, a further organ and nerve which react only to it as painfid? It is, indeed, inevitable that, under favourable conditions, such a pain-apparatus should be developed.
This recognizes the distinction between 'pleasure and pain ' on one side, and ' agreeableness and disagreeable- ness,' on the other, as developed by Miinsterberg. Pain as sensation-content is distinct from pain as quale of other contents. On my view, this is a distinction due to develop- ment. Pain, as sensation, is pain become habitual enough under constancy of stimulation, to have its own apparatus, i.e.y it is pain as peripheral function. Pain, on the other Organic Centralization. 485 hand, as quale oi mental content generally, is pain of irreg- ular stimulation, or pain of aceojfnnodation, i.e., pain as ceji- tral function. I do not agree, therefore, with Miinsterberg, in finding in the movements of flexion and extension, which my theory requires in common with his, the genetic sources of 'agreeable' or 'disagreeable' tone. The whole theory of development, as I have shown above, if it is to move at all, requires that this accommodation pain or pleasure be due, in the first instance, to stimulus, and that the flexion and extension movements be the organic mode of accommodation to the pleasure or pain-giving stimulus. Nevertheless, so great is organic complexity, when we come to take the principle of association into account, that, after all, in developed organisms, Miinsterberg may be right in making the flexion and extension movements themselves the direct basis of the agreeable and disagree- able quale. For we have seen in the case of emotion that movements at first purely purposive, serving utility or accommodation to stimulus, themselves get, by associa- tion, to represent the degree of success or failure in accom- modation, and so come themselves to give body to the emotion. In like manner, these flexion and extension movements may have passed, from being expressive or utility movements, to be the fore-runners of the condition which they at first served only to express. And it may well be that they are thus an intermediate link between quale pleasure-pain, and sensation pleasure-pain. This is supported by the evidence — as far as it goes — which locates the nerve apparatus of sensation pleasure-pain in the muscles. On this view, it is for reporting flexion and extension movements that this nervous apparatus has developed; these flexion and extension movements stand- 486 Habit and Accommodatiojt.
ing in place of the pleasure and pain-giving stimuli to which the organism has become accommodated.^ Now the same effect of * centralization ' is seen in the attention, as may be gathered from the positions already taken. Attention has been defined as genetically the reverberation of the 'excess' process as it has become fixed in habit. By the law of ' sensori-motor association,' this backward wave gets connected with all the sensory processes. Now just in as far as this wave is the same for different sensations, just in so far it tends to be 'cen- tralized' in a constant function — integrated into a habit — involving a regular set of motor phenomena, such as the wrinkling of the brows, setting of the glottis, etc., always found in acts of attention. The organism thus acquires a habit of accoimnodatioii, on a higher level. This is attention. When memory and imagination appear, this new form of response enables the organism to throw itself into attitudes favourable to the best reception and assim- ilation of material of all kinds.
Yet as with pain, so here. This attention-habit, this centralized function, is not all that the attention is. The original excess function must be kept in view. No pre- liminary setting of attention is an adequate accommodation to an intellectual stimulus — an idea still to be received; it is adequate only to hold stimuli by which it has been before excited. Each new accommodation to idea carries a motor excess discharge of its own, and this swells back into the sense of attention, making each act of attention, and each sense-type of attention, different, as was said above.
1 I may remark also, that this general position secures a number of minor explanations, which I do not stop to develop, — such as the contrast between ' systemic ' and ' single-organ ' pleasures and pains.
Organic Ccntralizatiou. 487 The terms of interaction of the two principles, finally, require that the reaction maintain its stimulus, and that this stimulus again repeat the reaction. The one type of reaction, therefore, which an organism must have, is a 'circular' or stimulus-repeating one. We have found it best to name this type of reaction Imitation. This is the UNIT, therefore, the essential fact, of all motor-develop- ment; and this shows the simplicity of the whole theory.
The place of imitation has now been made out in a tentative way throughout the development of the active life. It seems to be everywhere. But it is, of course, a matter of natural history that this type of action is of such extraordinary and unlooked-for importance. If we grant a phylogenetic development of mind, reaction of the imita- tive type, as defined above, may be considered the mode and the only mode of the progressive adaptation of the organism to its environment. The further philosophical questions as to the nature of mind, its worth and its dignity, remain under adjudication. We have learned too much in modern philosophy to argue from the natural history of a thing to its ultimate constitution and meaning — and we commend this consideration to the biologists. As far as there is a more general lesson to be learned from the considerations advanced, it is that we should avoid just this danger, i.e.^ of interpreting one kind of existence for itself, in an isolated way, without due regard to the other kinds of existence with which its manifestations are mixed up.
The antithesis, for example, between the self and the world is not a valid antithesis psychologically considered. The self is realized by taking in 'copies' from the world, and the world is enabled to set higher copies only through the constant reactions of the individual self upon it. Morally I am as much a part of society as physically I am a part of the world's fauna; and as my body gets its best explanation from the point of view of its place in a zoologi- cal scale, so morally I occupy a place in the social order; and an important factor in the understanding of me is the understanding of it.
The great question, which is writ above all natural his- tory records, is — when put in the phraseology of imitation, — What is the final World-copy, and how did it get itself set?
APPENDIX A.
NEW OBSERVATIONS ON CHILDREN, REPORTED IN THIS WORK.
Assimilation, 308.
Attention, in drawing, 87; in speech, 397, 453 f., 466.
Bashfulness, 147 ff.
Colour perception, 50 fF.
'Contrariness,' 145 ff.
Distance perception, 50 ff., 76 ff.
Drawing by children, 83 ff.
Dreaming, 137 ff.
Effects of ' recapitulation,' 32 f.
Effort, in reaching, 58 ff.; in holding up head and body, 389 f.
Emotions, 137 ff.
Epochs of development, 18.
Expression, facial, 123; E. of pain, 143.
Generalization, 325.
Handwriting, 91 ff.
Imitation, by drawing, 87 ff.; by voice and hands, 131; vocal and organic, 294; of persons, 115, 118 ff., 152 ff., 335 ff., 354, 357 ff., 374 ff.; persistent, 453 ff. Inhibition of movement, 127 ff. Lies, 337, note. Morals, 429.
Movements, of infants, 81 ff.; of weak-minded children, 407. New method of observation applied, 36 ff. Perception of distance and colour, 50 ff., 58 ff. Personality, suggestions of, see Suggestion; growth of, 335 ff. ^ Physiological suggestions,' see Suggestion.
490 Appendix B.
Reflection, rise of, 299.
Reflexes, 81 ff.
Recognition, of figure, 102; experiment on, 316; of pictures, 317, 333.
Right and left-handedness, 58 ff.
Self, sense of, 335 ff.
Suggestion, in children, 105 fT., 299; S. of sensations, 108 f.: physiolog- ical, 109 ff.; of sleep, 109, 115 f.; of position in bed, no; of sucking in sleep, 112; of a natural function, 1 13 f.; of personality, 115, 118 ff., 152 ff. (in bashfulness), 335 ff.; of food and clothing, 117 f.; complex, deliberative, 126 ff.; inhibitory, 143 ff.; con- trary, 145 ff.; experiments on, 383 f., 385, note.
Sense, of locality on the body, yj \ of agency, 134 f.; of self, 118 ff., Sleep indications in infants, 140 f.
Social sense, 120 ff., 156 ff. (in bashfulness), 338 f., 357 ff. Song, 440, note. Sympathy, 333. Tracery imitation, 87 ff. Unilateral reflexes, 82 f. ' Walking reflex,' 81 f. Weak-minded, movements of, 407.
APPENDIX B.
CASES OF THE USE OF THE RIGHT AND LEFT HANDS RE- SPECTIVELY, GATHERED FROM THE REPORT OF COLONEL GARRICK MALLERY, ON ' SIGN LANGUAGE AMONG THE NORTH AMERICAN INDIANS.'^ BY LESTER JONES, B.A., FELLOW PRINCETON COLLEGE.
" In the main part of Colonel Mallery's paper, where the cases cited are used as merely illustrative of the writer's own subject, the following data for the problem of right-handedness have been obtained: — ^ First Annual Report of the Bureau of Ethnology, Washington, 1879-80.
Appendix B. 491 No. of Cases Left Hand Right Hand Both Hands cited used used used " In about a thousand illustrations appended to the paper proper, the left hand is used distinctively alone twenty-three times.
" In the same appendix, in a dialogue of a hundred and sixteen signs used, the left hand acts distinctively alone five times.
" In the Natei narrative of seventy-five signs, the left hand is used distinctively alone three times, the right hand twenty-seven times.
" In the Patricio narrative of sixty-six signs, the left hand is used distinctively alone three times, the right hand twenty times.^ " It is worth observing that in the dialogue and two narratives, making a total of about three hundred signs, or less than one-third of the thousand signs cited, we find the left hand used alone eleven times, or about one-half the full number of times occurring in the entire thousand cases. This would seem to indicate that the more reflective the thought becomes, the more the left hand figures, while in the isolated more unpremeditated forms, it is the right hand that invariably springs into action.
" Two illustrations must suffice to show the general preference of the right hand over the left. In describing Indians conversing about the camp-fire, Mr. Mallery writes (p. 340): ' Two Indians whose blankets are closely held to their bodies by the left hand, which is necessarily rendered unavailable for gesture, will severally thrust the right from beneath the protecting fold, and converse freely. The same is true when one hand of each holds the bridle of a horse.' Again, this preference is well shown in the gesture sign for sunrise (p. 371): 'The forefinger of the right hand is crooked to represent the sun's disc, and pointed or extended to the left, then slightly elevated.
" ' In this connection it may be noted that when the gesture is carefully made in open country, the pointing would generally be 1 In the above series, only those cases have been considered in which the circumstances involved allow a choice of either hand.
492 Appendix B.
to the east, and the body turned so that its left would be in that direction.'
" The two-hand movement in making a sign is used, perhaps, as much as the right hand alone; yet in almost every case of the double-hand movement the right hand takes the initiative and plays the active role, with the left as merely supplementary. For example, the sign gesture for ' hard ' is made thus: open the left hand and strike against it several times with the right.
"Again, in making the sign gesture for 'done,' hold the extended left hand horizontally before the body, fingers pointing to the right, and cut edgewise downward, with extended right hand, past the tips of the left.
" Many signs appearing to be made by the left hand alone, on closer scrutiny can be included in the two-hand movement. For example, in the expression 'three white men,' 'white men' is made first with right hand alone; but to convey the meaning, the right hand must persist until the sign for three is made, which remains for the left hand to do. It is in reahty a double-hand movement with the left to be used as necessity requires, supple- mentary to the right."
Note by the Author. — It is evident that this report supports the view that the right hand was pre-eminently the * expressive ' member in pre-historic times. The cof?imon signs among different tribes, found also in deaf-mute sign language, show that many of these forms of expression are not late con- ventions, but rather matter of real aboriginal usage. If, then, they date back to the period before the development of speech, we have much reason for believing that right-handedness is originally a one-sided expressive function. Cf. Chap. IV., § 2, above.
INDEX.
Aboulia, 398 ff.
Abstraction, 328.
Accommodation, effects of, 24; sugges- tion as A., 167 f.; A. and Habit, 214 f.; A. in expression, 230 f.; in memory, Adaptation, organic, 170 ff.; current theory of, 180 ff.
Adults, suggestions in, 135.
Agency, sense of, 124 f.
Amusia, 440 ff.
Analogies, of development, 15 ff.
Animal, see Phylogenesis, Memory, Re- capitulation, Attention, Gregariousness.
Antithesis, law of, 242 ff.; A. and antago- nism, 245 ff.
Apperception, theory of, 308 ff.
Apraxia, 311.
Assimilation, theory of, 308 ff.
Association of ideas, physical basis of, 279 ff.; origin of, 361 ff.; sensori- motor, 459 ff.